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  • 1990-1994  (82)
  • 1955-1959  (1,063)
  • 1800-1809
  • Industrial Chemistry  (1,117)
  • gene transfer
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  • 1
    ISSN: 1432-203X
    Keywords: gene transfer ; selection for phosphinothricin resistance ; transgenic plants
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Protoplasts isolated from embryogenic suspension cultures of wheat (Triticum aestivum cv. Hartog) were electroporated in the presence of plasmid pEmuGN and/or pEmuPAT, which contained the reporter gene gus and selectable marker gene bar, respectively. Under optimised electroporation conditions, up to 0.9% of viable protoplasts displayed gus activity two days after electroporation. To select for phosphinothricin (PPT) resistant colonies, electroporated protoplasts were incubated for six weeks in a medium containing 10 μg/ml PPT. The cells surviving the selection were maintained as individual colonies on solid medium or as suspension cultures. More than 60% of these colonies exhibited tolerance to 40 μg/ml PPT when tested 10 months after initial selection. To date, 57 green plants have been regenerated from these colonies and 24 have been transferred to soil. Southern blot analyses of colonies and plants, using the bar gene sequence as the probe, confirmed transformation of the cells. Positive PAT assays of both regenerated colonies and plants indicated the presence of the bar gene product. These results provide a basis for the establishment of routine procedures for transformation of wheat by direct gene transfer into protoplasts.
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Plant cell reports 13 (1994), S. 145-148 
    ISSN: 1432-203X
    Keywords: muskmelon ; gene transfer ; Agrobacterium ; regeneration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Cotyledon explants of muskmelon (Cucumis melo L., cv. Amarillo Oro) seedlings were co-cultivated with disarmed Agrobacterium tumefaciens strain LBA4404 that contained the binary vector plasmid pBI121.1. The T-DNA region of this binary vector contains the Nopaline synthase/neomycin phosphotransferase II (NPTII) chimeric gene for kanamycin resistance and the Cauliflower Mosaic Virus 35S/β-glucuronidase (GUS) chimeric gene. After infection, the cotyledon pieces were placed in induction medium containing 100 mg/l kanamycin. Putative transformed shoots were obtained, followed by the development of morphologically normal plantlets. The transgenic nature of regenerants was demonstrated by polymerase chain reaction, Southern blot analysis, plant growth on medium selective for the transgene (NPTII) and expression of the co-transformed GUS gene. Factors affecting the transformation procedure are discussed.
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  • 3
    ISSN: 1573-5028
    Keywords: fertile transgenic barley ; gene transfer ; Hordeum vulgare ; neomycin phosphotransferase II ; particle bombardment
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Transgenic, fertile barley (Hordeum vulgare L.) from the Finnish elite cultivar Kymppi was obtained by particle bombardment of immature embryos. Immature embryos were bombarded to the embryonic axis side and grown to plants without selection. Neomycin phosphotransferase II (NPTII) activity was screened in small plantlets. One out of a total of 227 plants expressed the transferred nptII gene. This plant has until now produced 98 fertile spikes (T0), and four of the 90 T0 spikes analyzed to date contained the nptII gene. These shoots were further analyzed and they expressed the transferred gene. From green grains, embryos were isolated and grown to plantlets (T1). The four transgenic shoots of Toivo (the T0 plant) produced 25 plantlets as T1 progeny. Altogether fifteen of these T1 plants carried the transferred nptII gene as detected with the PCR technique, fourteen of which expressed the nptII gene. The integration and inheritance of the transferred nptII gene was confirmed by Southern blot hybridization. Although present as several copies, the transferred gene was inherited as a single Mendelian locus into the T2 progeny.
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  • 4
    ISSN: 1573-9368
    Keywords: gene transfer ; polyamines ; S-adenosylmethionine decarboxylase ; tobacco ; transgenic plants
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract S-adenosylmethionine decarboxylase (SAMDC; EC 4.1.1.50) is a key regulatory enzyme in the polyamine biosynthetic pathway. Numerous studies have shown that the enzyme activity and polyamine levels are generally correlated with cellular growth in plants, animals and bacteria. In order to gain more insight into the role of polyamines in plants, human SAMDC cDNA under control of the 35S promoter of cauliflower mosaic virus, along with a neomycin phosphotransferase gene, was transferred to tobacco (Nicotiana tabacum cv. Xanthi) viaAgrobacterium tumefaciens. Transgenic plants showed the presence of human SAMDC mRNA and a 2-4-fold increase in SAMDC activity. In the transformed tissues, putrescine levels were significantly reduced, while spermidine content was 2–3 times higher than the control tissues. Cellular spermine content was either increased or remained unchanged. Excised leaf segments from transformed plants frequently produced shoots even on callus inducing medium.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Transgenic research 3 (1994), S. 109-115 
    ISSN: 1573-9368
    Keywords: gene transfer ; metabolic engineering ; overexpression ; secondary metabolism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Plants interact with their environment by producing a diverse array of secondary metabolites. Many of these compounds are valued for their medicinal, industrial or agricultural properties. Other secondary products are toxic or otherwise undesirable and can reduce the commercial value of crops. Gene transfer technology offers new opportunities to modify directly plant secondary product synthesis through metabolic engineering. This article reviews some of the strategies which have been used to increase or decrease the synthesis of specific plant metabolites, as well as methods for expanding the biosynthetic capabilities of individual species.
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  • 6
    ISSN: 1573-9368
    Keywords: Solanum tuberosum ; genetic modification ; transformation ; gene transfer ; genetic isolation ; risk assessment
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Information on the extent of transgene dispersal by pollen to adjacent potato plots and to related weed species is an important requisite for risk assessment; a procedure followed before novel transgenic plants are evaluated under field conditions. The purpose of the investigation was to determine the frequency of cross-pollination between potato (Solanum tuberosum) plants at different distances, using a kanamycin resistnace transgene (nptII) as a selectable marker. All potato plants were from the variety Désirée. Non-transgenic potato plants, used as potential recipients of transgene-containing pollen, were planted in 12 sub-plots, at distances of 0–20 m from the nearest transgenic potato plants. Seeds harvested from the non-transgenic plants were screened for resistance to kanamycin, and molecular methods were used to confirm that resistant progeny contained thenptII gene. Where transgenic and non-transgenic potato plants were in alternate rows (leaves touching), 24% of seedlings from the non-transgenic parent plants were kanamycin-resistant. Comparable seedlings from plants at up to 3 m distance had a resistance frequency of 2%, at 10 m the frequency was 0.017% and at 20 m no resistant progeny were observed. Plants of the weed speciesS. dulcamara andS. nigrum were also planted close to the transgenic potatoes to test for evidence of hybridization, and no kanamycin-resistant seedlings were observed among progeny fromS. dulcamara andS. nigrum. This investigation provided evidence that the extent of gene dispersal from transgenic potatoes to non-transgenic potatoes falls markedly with increasing distance, and is negligible at 10 m. There was, also, no evidence of transgene movement from potato toS. dulcamara andS. nigrum under field conditions. These data will be valuable in defining genetic isolation procedures for the early field evaluation and the use of novel transgenic potato genotypes.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Transgenic research 3 (1994), S. 263-278 
    ISSN: 1573-9368
    Keywords: Brassica napus ; oilseed rape ; transgenic plants ; interspecific hybridization ; gene transfer ; risk assessment
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Before novel transgenic plant genotypes are grown outside containment facilities and evaluated under field conditions, it is necessary to complete a risk assessment to consider the possible consequences of that release. An important aspect of risk assessment is to consider the likelihood and consequences of the transgene being transferred by cross-pollination to related species, including other crops, weeds and ruderal populations. The purpose of this report is to review the literature to assess the ease with whichBrassica napus can hybridize with related species. The evidence for hybridization is considered at three levels: a) by open pollination, b) by hand pollination and c) by the use ofin vitro ovule and embryo rescue techniques; and also examines the fertility and vigour of the F1, F2 and backcross generations. Four species are reported to hybridize withB. napus by open pollination:B. rapa andB. juncea using fully fertile parents; andB. adpressa andR. raphanistrum using a male-sterileB. napus parent. Seventeen species are reported to form hybrids (including the four species above) withB. napus when pollination is carried out manually. At least 12 of these species were unable to form F2 progeny, and eight were unable to produce progeny when the F1 was backcrossed to one of the parental species. Many factors will influence the success of hybridization under field conditions, including: distance between the parents, synchrony of flowering, method of pollen spread, specific parental genotypes used, direction of the cross and the environmental conditions. Even where there is a possibility of hybridization betweenB. napus and a related species growing in the vicinity of a release, poor vigour and high sterility in the hybrids will generally mean that hybrids and their progeny will not survive in either an agricultural or natural habitat.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Transgenic research 3 (1994), S. 401-405 
    ISSN: 1573-9368
    Keywords: gene transfer ; transgenic ; swine ; growth hormone ; PEPCK-bGH
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Transgenic pigs were created that harboured a phosphoenol pyruvate carboxykinase-bovine growth hormone construct (PEPCK-bGH). Four founder animals and two transgenic offspring from one line were evaluated between 61/2 and 12 months of age. There was no evidence of severe hepatic or renal lesions in these pigs, which characterised transgenic PEPCK-bGH mice previously described. While glomerular and tubular lesions in kidney sections were not identified in the transgenic pigs, mesangial cell proliferation was observed in two transgenic offspring from a single line. Additionally, glomerular size was significantly increased in four of four puberal transgenic swine when compared to age- and sex-matched controls (28.30±4.1 vs. 14.2±2.7×105 μm3; representing 3 transgenic lines,p〈0.05). Surprisingly, no mature adipocytes were observed in subcutaneous sections obtained in transgenic GH pigs. Histological evaluation of these transgenic pigs further illustrates the requirement for precise control of growth-related genes and their protein products.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Plant cell, tissue and organ culture 36 (1994), S. 291-301 
    ISSN: 1573-5044
    Keywords: clesteroviruses ; cytopathology ; fleek disease ; gene transfer ; tissue culture ; virus purification
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Agrobacterium rhizogenes-mediated transformation was applied toVitis spp. andNicotiana spp. infected by different grapevine phloem-limited viruses (grapevine fleck virus, grapevine virus A, grapevine virus B) to obtain root cultures for virus purification. All plant species were successfully transformed, and several clones were established in liquid culture. Transformed grapevine roots contained as much virus as non transformed roots and more than leaves, as assessed by ELISA and thin sectioning. Likewise, transformed roots ofNicotiana benthamiana Domin. contained in average more GVA than leaves, especially those at the base and the top of the plant, whereas withNicotiana occidentalis wheel., GVB was apparently less concentrated than in leaves.Nicotiana root grew faster than those ofVitis. All viruses multiplied and persisted in root cultures, which were successfully used for purification. Virus yields were the same (GFkV and GVB) or higher (GVB) than those reported in the literature. Grapevine roots may prove useful for culturing and purifying other non-mechanically transmissible grapevine viruses.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Transgenic research 3 (1994), S. 13-19 
    ISSN: 1573-9368
    Keywords: gene transfer ; electroporation ; stable transformation ; protoplasts ; transgenic trees ; Populus tremula x P. alba
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Protoplasts from leaflets ofin vitro cuttings were electroporated in osmotically adjusted and buffered solutions containing plasmid DNA: pABD1, carrying thenptII gene for resistance to neomycin; pGH1, carrying a mutant acetolactate synthase gene,als, for resistance to sulfonylurea; and pGSFR781A, carrying a synthetic phosphinothricin acetyltransferase (pat) for resistance to phosphinothricin (Basta). Gene transfer was repeatedly efficient, without use of carrier DNA, in the range of one transformant for 105 to 104 protoplast-derived cell colonies. This was probably due to the high plating efficiency (30%) of protoplasts in our culture process. Selection for expression of foreign genes was applied in liquid medium and repeatedly achieved with 30 μM paromomycin for NPTII, 200 nM chlorsulfuron for the mutant ALS ofArabidopsis and 25 μM phosphinothricin for PAT expression. Integration of foreign genes into genomic DNA of resistant poplar trees was demonstrated by Southern blot hybridizations, which revealed that for some transformants practically no other part of the vector plasmid than the selected gene was integrated. Effective processes for protoplast culture, efficient selection at the cell colony stage and gene transfer will provide new possibilities in poplar breeding.
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  • 11
    ISSN: 1573-5028
    Keywords: antifreeze proteins ; gene transfer ; preproprotein processing ; α-helix stability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Expression of fish antifreeze protein (AFP) genes in plants is a possible means of increasing their frost resistance and freeze tolerance. Initial work involved transfer into tobacco of an AFP gene from winter flounder which codes for the alanine-rich, α-helical Type I AFP. Plants were transformed with a gene construct in which the preproAFP cDNA was inserted between the cauliflower mosaic virus 19S RNA promoter and the nopaline synthetase polyadenylation site. Although transgenic plants produced AFP mRNA, no AFP was detected on western blots. Re-evaluation of AFP expression in these transgenic plants showed that AFP accumulated to detectable levels only after exposure of the plant to cold. Extracts of plants incubated at 4°C for 24 h contained a protein which co-migrated with winter flounder proAFP and was cross-reactive to Type I AFP antisera. Two other minor protein bands of slightly higher apparent M r also cross-reacted with the antisera and are thought to represent processing intermediates. The proAFP was unique to the transgenic plants and was absent in extracts taken prior to cold exposure. AFP levels increased over the first 48 h of cold incubation then remained stable. Since the α-helix content of Type I AFP has been shown to decrease markedly at warmer temperatures, we postulate that Type I AFP stability in transgenic plants is dependent on its secondary structure.
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  • 12
    ISSN: 1573-9368
    Keywords: rice ; small cell groups ; electrophoresis ; gene transfer ; stable integration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A new method has been developed to introduce foreign DNA into rice cells. Gene delivery occurred when an electrophoretic drive with cycles of intervallic electric field was applied to a mixture containing partially digested small cell groups (SCGs) and plasmid DNAs. Gene transfer efficiency was evaluated by the detection of β-glucuronidase (GUS) activity resulting from expression of a chimaeric plasmid DNA. The optimal combination of treatment conditions (3 V/cm, 30 s pulse and 30 min electrophoretic run) produced a frequency of up to 8.2% of blue cells in transformed microcalluses 40 days after culture of treated SCGs without selection for kanamycin resistance. Southern hybridization showed that the foreign gene had integrated into the chromosomal DNA. These results demonstrate that pulsed electrophoretic drive is applicable to the transfer of foreign genes into plant cells.
    Type of Medium: Electronic Resource
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  • 13
    Electronic Resource
    Electronic Resource
    Springer
    Transgenic research 2 (1993), S. 125-133 
    ISSN: 1573-9368
    Keywords: chicken embryo ; gene transfer ; retroviral vector ; cloned DNA
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The application of transgenic technology to domestic poultry offers an alternative means to conventional practice for improvement of this highly productive agricultural species. The hen's reproductive system has unique characteristics which have imposed limitations on the use of established methods for artificial gene transfer. In this article, we review the various strategies that have been adopted to overcome the problem. Target sites for gene insertion include the fertilized ovum, the blastodermal embryo in the unincubated egg, and the primordial germ cells. Notable success in obtaining somatic and germline transformation has been achieved with the use of retroviral vectors to infect the blastodermal embryo. Current attempts to introduce DNA directly into the genome, without resort to pathogen-derived vectors, are discussed.
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  • 14
    Electronic Resource
    Electronic Resource
    Springer
    Plant cell, tissue and organ culture 33 (1993), S. 247-250 
    ISSN: 1573-5044
    Keywords: gene transfer ; GUS gene-marker ; particle acceleration ; transient expression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Construction and operation of an airgun device for transient gene-expression studies in monocots is described. Compressed air in a cylinder of an airgun was used as the source of propulsion for DNA-coated gold or tungsten particles. Under a partial vacuum of 700 mm Hg, velocity of the macrocarrier was measured at 520 m sec−1 and 432 m sec−1 at atmospheric pressure. Optimum distance from the stopping plate to different target cells during bombardment ranged from 4 to 7 cm. Mean transformation efficiency of the GUS-gene marker was estimated at 350 transformants per 65 mg fresh weight of the maize cultured cells. Up to 200 GUS transformed cells were detected per 100 mg of embryogenic rice callus. Use of gold flakes or tungsten powder as microcarriers resulted in similar transformation rates. No transformation was observed in any cells when DNA constructs contained prokaryotic translation initiation sequences for the GUS gene. Based on transient GUS assays, further modification of the airgun device will likely be necessary to obtain high stable transformation rates.
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  • 15
    ISSN: 1573-6830
    Keywords: herpesvirus vector ; gene transfer ; neuron-specific enolase (NSE) promoter ; lacZ, stereotactic delivery ; rat CNS
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary 1. Herpesvirus infection with genetically engineered vectors is a way to deliver foreign gene products to various cell populations in culture andin vivo. Selective neuronal gene expression can be achieved using the neuron-specific enolase (NSE) promoter regulating expression of a transgene placed in and delivered by a herpesvirus vector. 2. We sought to determine the anatomical specificity and efficiency of herpesvirus-mediated gene transfer into the rat brain following placement of virus particles carrying a transgene (lacZ) under control of the NSE promoter. The virus utilized was thymidine kinase (TK) deficient and therefore replication deficient in the brain. 3. Infusion of 106 plaque-forming units of virus into the striatum caused a limited number of striatal neurons to express thelacZ transgene mRNA and protein product 7 days postinfection. In addition, small numbers of neurons expressing the transgene mRNA and protein were found ipsilateral to the viral injection in the frontal cortex, substantia nigra pars compacta, and thalamus. Neurons at these anatomic loci project directly to the striatal injection site. No other cells within the brains of injected animals expressed thelacZ gene. 4. While this herpesvirus NSE vector was capable of introducing novel functional genetic information into postmitotic neurons within defined neuroanatomic constraints, the numbers of neurons expressing detectable levels ofβ-galactosidase was minimal. The calculated efficiency of delivery and transgene expression at 7 days postinfection was 1 transgenic neuron per 104 virus particles infused. 5. We conclude that NSE probably is not an optimal promoter for use in gene delivery to CNS neurons in herpesvirus vectors and that the efficacy of gene delivery using other neuron-specific promoters placed at various sites in the herpes viral genome needs to be explored.
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  • 16
    Electronic Resource
    Electronic Resource
    Springer
    Methods in cell science 15 (1993), S. 69-71 
    ISSN: 1573-0603
    Keywords: protoplast fusion ; gene transfer ; alkaline phosphatase ; expression cloning
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A method is described that facilitates performing a large number of protoplast fusions to mammalian cells simultaneously and successfully. This method makes it possible to circumvent typical hurdles to the use of transient expression in mammalian cells, facilitating expression cloning of DNA enoding the newly detected gene product of interest. The original in vitro assay used to define the new activity is of interest, adapted to microtiter plates, combined with protoplast fusion, extends the reach of expression cloning to such cases as products of a rare message, or activities involving a multisubunit or unstable protein or both.
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  • 17
    Electronic Resource
    Electronic Resource
    Springer
    Euphytica 73 (1993), S. 109-114 
    ISSN: 1573-5060
    Keywords: wild-germplasm ; interspecific-hybridization ; gene pools ; introgression ; gene transfer
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Wild species which are crossable to cultivated pea, lentil, and chickpea have been collected and are maintained in major germplasm collections throughout the world. Wild species of Vicia crossable to the cultivated faba bean have not been found. The primary, secondary, and tertiary gene pools of the cool season food legumes represent potential genetic diversity that may eventually be exploited in cultivated types to overcome biotic and abiotic stresses. Technical difficulties in obtaining hybrids beyond those within the primary gene pool is a major obstacle. Reproductive isolation, embryo breakdown, hybrid sterility, and limited genetic recombination are major barriers to greater use of wild germplasm. Conventional crossing has been successful in producing interspecific hybrids in Lens, Cicer and Pisum and those hybrids are being evaluated for desired recombinants. In vitro culture of hybrid embryos has been successful in overcoming barriers to wider crosses in Lens. The successful transfer of genes from wide sources to cultivated types can be assisted by repeated backcrossing and selection designed to leave behind undesired traits while transferring genes of interest. Molecular marker assisted selection may become a valuable tool in the future use of wild species. In general, too little is known about the possible genetic variation available in wild species that could be valuable in developing resistance to biotic and abiotic stresses. Current efforts on the use of wide hybridization in the cool season food legumes are reviewed and discussed.
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  • 18
    ISSN: 1573-5060
    Keywords: gene cloning ; gene transfer ; virus and insect resistance ; genome analysis ; DNA figerprinting
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The potential of plant gene technology encompasses a multitude of different techniques ranging from the isolation of useful genes, their characterization and in vitro manipulation to the reintroduction of the modified constructs into target plants, where they are expressed at a rate that alters the phenotype of the plants. Genome analysis, on the other hand, aims at characterizing the genome architecture and function(s). Plant gene technology has catalyzed progress in plant breeding, as will be exemplified by a few examples, but has not yet been applied to food legume improvement on a large scale. Genome analysis, however, has a series of practical implications, as is illustrated by the successful introduction of DNA fingerprint and PCR fingerprint techniques to chickpea (Cicer arietinum L.) breeding and Ascochyta rabiei pathotyping. The present overview addresses both areas of plant molecular biology to illustrate their potential for food legume breeding.
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  • 19
    ISSN: 1573-5028
    Keywords: Brazil nut ; 2S albumin gene ; gene transfer ; Phaseolus vulgaris ; particle bombardment
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Bean (Phaseolus vulgaris L.) mature embryos were transformed using biolistic methods with a plasmid containing 2S albumin and β-glucuronidase structural sequences, both under the control of the 35S CaMV promoter. We have shown that chimaeric tissues could be obtained and that both structural sequences were expressed to similar levels.
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  • 20
    ISSN: 1573-5044
    Keywords: Agrobacterium transformation ; Cucumis sativus ; gene transfer ; neomycin phosphotransferase ; tissue culture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Cucumber (Cucumis sativus L.) petiole and leaf segments of two pickling genotypes were transformed with Agrobacterium tumefaciens strain LBA 4404, an octopine Ti-plasmid deletion mutant that is avirulent (disarmed plasmid), but to which were added T-DNA inserts on binary plasmids (pBIN 19, ca. 10 kb, and pCGN 783, ca. 25 kb). Expression of neomycin phosphotransferase (NPT II) encoding resistance to the aminoglycoside kanamycin was used as a selectable marker. Factors which influenced the frequency of callus development on medium containing kanamycin (75 mg l-1) were explant size, bacterial concentration and length of exposure, cocultivation period, and presence of acetosyringone. The optimal procedure involved exposing segments of petiole (4–6 mm) or leaf (0.5 cm2) segments to a bacterial suspension (108 cells ml-1) containing 20 μM acetosyringone for 5 min, followed by a 48 h cocultivation period on a tobacco feeder layer. Explants were placed on MS medium containing 500 mg l-1 carbenicillin, 75 mg l-1 kanamycin, and NAA/BA (5.0/2.5 μM) or 2,4-d/BA (5.0/5.0 μM) and subcultured twice, each after a 2–3 week period, onto fresh media. The overall frequency of transformed callus was 20–50%; the frequency of plantlet regeneration from transformed callus was 8–15%. Twenty-one out of 23 individual plants recovered from two genotypes of pickling cucumber were NPT II positive (transformation frequency of 9%). Copy number of the NPT II gene insert (35S-NPT II-3′ fragment, ca. 2.2 kb) in three transformed plants was estimated at ten per haploid genome, indicative of multiple insertions within the cucumber genome. Multimers of the gene (visible as 4.4 and 6.6 kb fragments in Southern analysis) were detected in one plant, suggestive of tandem duplications or repeats. Progeny from a cross between this transformed plant and a nontransformed control showed segregation for the NPT II gene in dot-blot assays; at least 24 plants out of 32 were kanamycin positive. Copy number in the progeny was variable, and ranged from none to ten.
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  • 21
    ISSN: 1573-4919
    Keywords: human growth hormone ; rat pituitary tumor cells ; tissue-specificity ; gene transfer ; DNase 1 footprinting
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Summary Placental chorionic somatomammotropin (hCS-A or B) and growth hormone variant (hGH-V) are members of the human growth hormone family, and are related by structure and function to pituitary growth hormone (hGH-N). However, while the hGH-N gene is expressed specifically in the anterior pituitary, hGH-V and hCS are produced in the placenta. Hybrid hGH-N, hGH-V and hCS-A genes containing 5′-flanking sequences, including the endogenous promoter, are preferentially expressed in rat pituitary tumor (GC) cells, after gene transfer. Since interaction with a pituitary-specific protein (Pit 1) is required for efficient hGH-N as well as rat growth hormone (rGH) gene expression in GC cells, binding of pituitary proteins to the hGH-V and hCS-A promoter sequences was investigated. Rat Pit 1 binds at two locations on the hGH-N gene, a distal (−140/−107) and proximal site (−97/−66), in a similar manner to that observed with the rGH gene. By contrast, efficient Pit 1 binding was seen only to the distal site of the hGH-V gene and the proximal site of the hCS-A gene. Although binding of a protein to the distal hCS-A sequences was observed, the site of interaction was truncated (−140/−116), not pituitary-specific, and was more consistent with the binding of Sp1. These data indicate that rat Pit 1 binds to the placental hGH-V and hCS-A genes and correlates with their promoter activity in GC cells after gene transfer. However, the data also indicate that rat Pit 1 binds to human and rat pituitary growth hormone in a similar manner (two sites of interaction) and that the pattern of binding is distinct from the placental members of the hGH gene family. These data indicate that human Pit 1, unlike the rat equivalent, might distinguish these genes functionally (tissue-specifically) as well as structurally.
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  • 22
    Electronic Resource
    Electronic Resource
    Springer
    Euphytica 55 (1991), S. 157-169 
    ISSN: 1573-5060
    Keywords: gene transfer ; genetic manipulation ; chimaeric genes ; legumes ; transformation ; somatic hybridisation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary The merits and limitations of somatic cell techniques involving Agrobacterium-mediated transformation, direct gene transfer and protoplast fusion, are discussed in relation to the genetic improvement of forage and grain legumes. Whilst progress with legumes is limited compared to that with plants of other families such as the Solanaceae, the fact that many legumes are readily amenable to tissue culture now permits somatic cell techniques to be targetted to these species. Future development of the subject will necessitate close collaboration between molecular biologists and plant breeders to enable novel plants generated by in vitro technologies to be incorporated into conventional breeding programmes.
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  • 23
    Electronic Resource
    Electronic Resource
    Springer
    Neurological sciences 12 (1991), S. 257-268 
    ISSN: 1590-3478
    Keywords: Human muscle cultures ; clones ; nerve-muscle cocultures ; cell lines ; heterokaryons ; myoblast transfer ; gene transfer ; Myo D ; cybrid clones ; hereditary human myopathies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Sommario L'Autore illustra l'utilità e i limiti delle colture di muscolo umano nello studio delle miopatie umane ereditarie. In particolare nelle miopatie dovute a difetti di enzimi-specifici muscolari, l'utilizzo di tecniche di cocoltura muscolo-nervo con avanzato grado di maturazione muscolare permette di delucidare i meccanismi molecolari patogenetici di tali malattie. L'uso di avanzate tecniche di biologia molecolare e cellulare, quali linee permanenti, trapianto di mioblasti, trasferimento genico e di mitocondri, oltre che fornire utili informazioni a livello molecolare potranno trovare applicazione, in futuro, persino nella terapia di molte miopatie ereditarie.
    Notes: Abstract In this article I illustrated the use of regenerating human muscle cultures for studying the hereditary human myopathies. Although some of the data are still controversial, they do point up the great potential of this “in vitro system”. For hereditary myopathies due to developmentally regulated proteins that are expressed only at a more advanced stage of muscle differentiation, the use of highly differentiated nerve-muscle cocultures might contribute significantly to a better understanding of their developmental pathogenesis. More advanced techniques (permanent human muscle cell lines, heterokaryons, myoblast transfer, gene transfer, myogenic conversion of human non-muscle cells, cybrid clones) may provide a great deal of information at molecular level and may also have practical applications in the diagnosis or even in the treatment of hereditary human myopathies.
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  • 24
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    Electronic Resource
    New York, N.Y. : Wiley-Blackwell
    Journal of Cellular Biochemistry 45 (1991), S. 353-358 
    ISSN: 0730-2312
    Keywords: bone marrow ; peripheral blood ; gene transfer ; IL-2 ; neo gene ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Human T-lymphocytes are long lived, easily accessible, mature, and capable of proliferation. They are theoretically a suitable target for retroviral mediated gene transfer. To test this hypothesis, normal human T-cells obtained from bone marrow and peripheral blood were stimulated with phytohemagglutinin (PHA) and infected 24 h later with the retroviral vector N2 which carries the bacterial neo gene. T-lymphocytes were propagated in culture for up to 14 weeks with interleukin-2 (IL-2). Analysis by whole cell RNA dot/blot using a single stranded RNA probe demonstrated persistent expression of the neo gene. Preliminary functional studies revealed that both helper and suppressor functions were preserved in the infected cells in culture. These results demonstrate that normal T-cells are capable of long-term expression of genes introduced by retroviral mediated gene transfer and are potential target cells for somatic gene therapy.
    Additional Material: 3 Ill.
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  • 25
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Formaldehyde is produced industrially from methanol by partial oxidation of oxidative dehydrogenation. In these processes, water is formed as a by-product. Anhydrous formaldehyde is required for many syntheses and, therefore, its production is of potential interest. In the present study, catalysts based on alkali compounds were found to be active in the dehydrogenation of methanol if absence of oxygen. Sodium carbonate doped with indium shows a selective of up to 75% for methanol conversion not exceeding 60%.
    Additional Material: 10 Ill.
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  • 26
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Copper and potassium containing Fe/Mn oxide catalysts for Fischer-Tropsch synthesis were investigated by X-ray microprobe technique, scanning electron microscopy, low-temperature argon sorption and carbon monoxide and carbon dioxide chemisorption at -80°C. The specific surface areas of the catalysts depend on the preparation method, e.g. addition of K or Cu by coprecipitation leads to an increase while impregnation results in a decrease in surface area. The resulting samples are inhomogeneous, as shown by all method. Mn and especially K accumulated on the surface of the catalysts. Addition of Cu and K considerably altered the selectivity and activity of the Fe/Mn oxide catalyst. High potassium contents produced high olefin to paraffin ratios but these catalysts became rapidly deactivated. Copper and a very small addition of potassium led to a very low olefin to paraffin ratio but showed a high and constant activity.
    Additional Material: 4 Ill.
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  • 27
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A new model of suspended bed of droplets for describing the vaour or gas the vapour or gas velocity at the flooding point in packed of columns for rectification and absorption under vacuum and normal pressure is presented metallic, ceramic and plastic packings with diameters of 8-90 mm as well on sheet metal and gauze packings, in a wide range of liquid and vapour loads. Approximately 650 literature measurements and own data were evaluated. The mean relative error in determining the gas velocity at flooding point is less than ±5%. On the basis of the double layer model, a new equation was derived for the hold-up at flooding point, which is needed for the calculation of the flooding gas velocity. An example of calculations for sample applications is also included.
    Additional Material: 6 Ill.
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  • 28
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    Weinheim : Wiley-Blackwell
    Chemical Engineering & Technology - CET 13 (1990), S. 229-237 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A new laboratory plant for batch cooling crystallization is described, which allows to maintain the supersaturation at a constant level during an experimental run. A method for continuous supersaturation measurements has been developed, using a density meter and a hydrocyclone. Experimental results obtained from a seeded solution in constant supersaturation cooling mode and at constant cooling rate are compared. In the case of a constant cooling rate, the supersaturation passes through a sharp maximum, whereby effective nucleation is enhanced. As a consequence, a smaller median crystal size is obtained than for cooling at constant supersaturation. Equation for controlled cooling at a constant supersaturation require an accurate description of the effective rate of nucleation. Therefore, the mechanical stress, to which the crystals are subjected, must be included as the main source of new nuclei. This is shown by the influence of stirrer on batch time.
    Additional Material: 9 Ill.
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  • 29
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    Weinheim : Wiley-Blackwell
    Chemical Engineering & Technology - CET 13 (1990), S. 241-251 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Pyrolysis of 2,3-dimethyl butane (DMB) was carried out in a quartz flow reactor in the temperature range from 740 to 1032 K at normal pressure. The input concentration of DMB was 3.3 × 10-3 mol/1 using argon as diluent. Reaction time ranged between 3.1 and 3.9 s. The following products were analyzed by two-column gas chromatography: hydrogen, methane, ethene, propane, propene, butenes, butadiene, 2-methyl-2-butene, isoprene, benzene and toluene. Compared to thermal decomposition of n-hexane under similar experimental conditions, the main difference concerned the formation of ethylene, ethane and branched alkanes. A reaction model, based on elementary reactions, was developed to predict the experimental results and to verify our data basis of elementary reactions under different conditions. The model gives a quantitative description of the complex chemistry of the process. In addition, an algorithm is presented for model reduction.
    Additional Material: 6 Ill.
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  • 30
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    Weinheim : Wiley-Blackwell
    Chemical Engineering & Technology - CET 13 (1990), S. 264-272 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: This paper describes general, asymptotic and speculative relationships which can be deduced directly from the time-averaged form of the basic, partial-differential model for the conservation of mass and momentum in fully developed turbulent flow of constant-property fluids through round and parallel-plate channels. Such relationship are shown to provide insight as well as useful forms for correlation. Several analogies for flow in round tubes and between parallel plates which have generally been overlooked are reexamined and extended. A generally overlooked anomaly which occurs for flow in concentric, circular annuli, for flow between plates of non-identical roughness, and for the combination of forced and wall-Ind.uced flow between parallel plates is also is noted. The data needed to test the above analogies and to quantify the deviations, if any identified, as well as those needed to generalize the anomalous behavior.
    Additional Material: 1 Ill.
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  • 31
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    Weinheim : Wiley-Blackwell
    Chemical Engineering & Technology - CET 13 (1990), S. 298-303 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Adsorption isotherms for n-hexane and methanol in mordenite and ZSM5 in the temperature range from 323 K to 473 K were found to be of type 1. The adsorbate-adsorbent interaction (C1) and adsorbate-adsorbate interaction (C2) wee computed according to Bradley and Wilkins model, whereas the Rees and Williams model predicts the adsorption characteristics. Finally, the thermodynamic parameters such as ΔGo, ΔSo, ΔHo, K, K+ have been evaluated for the sorption of n-hexane in mordenite and ZSM5.
    Additional Material: 13 Ill.
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  • 32
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Incineration processes are critical for the environment. SO2 and NOX removal with processes is nowadays commonplace. Up to now, heavy metal were recovered via precipitation. The alternative use of liquid ion exchange techniques offers an easy re-use of the heavy metals, which are obtained as concentrates. A separation process is described, starting from laboratory experiments and ending with pilot plant field tests. A cost comparison for extraction, permeation and precipitation gives the scope of the necessary expenses for such environmentally controlled processes.
    Additional Material: 13 Ill.
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  • 33
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: In industrial processes, the reduction of nitrogen oxides by ammonia on activated carbons is carried out at temperatures between 90 and 190 °C. Adsorption of NO and NH3 on the catalyst was investigated separately. Reactions models for NO-reduction by carbon and ammonia were derived from experiments carried out in an integral reactor. In each case, the formation of an adsorbed (NO2)-complex is an important step. The kinetics of both reactions was described by modified Langmuir-Hinshelwood equations.
    Additional Material: 20 Ill.
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  • 34
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    Weinheim : Wiley-Blackwell
    Chemical Engineering & Technology - CET 13 (1990), S. 289-297 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A new stage-to-stage method has been developed for the calculation of NXx absorption columns. Each stage of the absorption column is simulated as a combination of a bubble column reactor (absorption) and an adiabatic plug for reactor (oxidation). The bubble column reactor is modelled as two single stirred tank reactors, one as a gas-phase and one as a liquid-phase reactor, both coupled by mass and heat transfer. In this hydrodynamic model, a dynamic approach is adopted, in which the gas-phase transport of N2O4 is the limiting step for the absorption. A gas-phasepseudo-enhancement for factor for N2O4 is therefore introduced. The balance equations for a single phase of the bubble column are solved with a Newton-Raphson algorithm. The entire column calculation is divided into a gas and a liquid side. On both sides, the stage-to-stage method is applied in such way that the overall calculation is performed as a loop process. The direction of the loop calculation follows that of the flow: gas-side upwards and liquid-side downwards.
    Additional Material: 5 Ill.
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  • 35
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    Weinheim : Wiley-Blackwell
    Chemical Engineering & Technology - CET 13 (1990), S. 376-383 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A theoretical and experimental study of the electrohydrodimerization process to produce adiponitrile is used to determine an appropriate reaction model. From numerical simulations of five proposed reaction schemes and subsequent comparison with experimental data, the most favoured route is via an anion, intermediate of acrylonitrile. This route, a five step reaction involving electrochemical and chemical reaction in a diffusion/reaction layer, gives good predictions of product distributions over a wide range of current densities and acrylonitrile concentrations of product distributions over a wide range of current densities and acrylonitrile concentrations.
    Additional Material: 12 Ill.
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  • 36
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    Weinheim : Wiley-Blackwell
    Chemical Engineering & Technology - CET 13 (1990), S. 397-402 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: This paper presents a method of transforming the non-liner regression problem in the kinetic study of complex heterogeneous catalytic reactions into a linear regression problem. Application of this method reduced the number of parameters to be estimated by n-1, where n is the number of independent reactions. In addition, a stepwise model discrimination strategy in introduced to reduce the number of equation sets ad equations in the set undergoing parameter estimation. These two new approaches are very advantageous in reducing the computation effort, especially when the number of independent reactions is large. The linear regression method and the stepwise model discrimination strategy are successfully applied in the kinetic study of the methanol synthesis system in which the formation rates of methanol, methane, ethanol and ethane are considered.
    Additional Material: 4 Tab.
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  • 37
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    Weinheim : Wiley-Blackwell
    Chemical Engineering & Technology - CET 13 (1990), S. 41-49 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: This contribution presents the mechanical data of high performance carbon fibres currently available on the market, based on experimental studies on stabilization and pyrolysis of PAN (SAF) from Courtaulds. The effects of stabilization and carbonization temperatures on the properties as well as on the ultra- and crystalline structures of the fibres are shown in more detail.
    Additional Material: 22 Ill.
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  • 38
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The residence time distribution in liquid phase was measured in a cocurrent upflow packed bed reactor for the system methanol-hydrogen at low Reynolds numbers and at elevated pressure. The plug flow with axial dispersion model was used to describe mixing in the system. The imperfect pulse method was used to measure the system response to a tracer pulse input. The parameters were calculated using the weighted moments method. The influence of the weighting factor was investigated. The experimental and theoretical outputs, as calculated by convolution, agreed very well. Different types of correlations were used for the Bodenstein number and liquid hold-up. From these correlations, the optimal one was selected for each parameter. A comparison was made between the ordinary moments and the weighted moments methods which led to the conclusion that the latter method is superior with respect to the accuracy of the estimated parameters and therefore strongly recommended.
    Additional Material: 11 Ill.
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  • 39
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: In the first part of this paper, a mathematical model is presented for a liquid fluidized bed bioreactor using immobilized enzymes with reversible Michaelis-Menten kinetics. The model is based on the axial dispersion model for the bulk liquid phase. Inter- and intraparticle mass transfer as well as enzyme catalyzed reaction inside the porous beads are considered. The overall efficiency of the biocatalysts is calculated by a numerical routine. For the calculation of the concentration profile inside the reactor, a semi-analytical solution is derived which takes into account the height dependence of the effectiveness factor.
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  • 40
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Even though the influence of solids concentration in the feed on the separation efficiency of hydrocyclones has long been recognized, a systematic research on the change in pressure drop across the hydrocyclone and the latter's separation characteristics has thus far been lacking. If all other operating parameters are kept constant, an increase in feed concentration generally leads to a coarser cut size, reduced sharpness of separation and a rise in pressure drop. Apart from the particles hindering one another's radial motion, the limited capacity of the apex valve and the changes in the flow field within the hydrocyclone cause additional particles to be entrained by the overflow. The flow ratio thus becomes an additional parameter in determining the cyclone efficiency. A theoretical model, which takes these effects into account, has been developed and successfully tested against experimental data.
    Additional Material: 12 Ill.
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  • 41
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    Weinheim : Wiley-Blackwell
    Chemical Engineering & Technology - CET 13 (1990), S. 63-71 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Bench scale experiments and computer simulations of transient crystal size distributions obtained in a 1.4 m3 sucrose crystallizer, which prove the existence of nuclei stock, are presented. This stock represents a large number of non-growing nuclei, which can be activated at increased supersaturations. The nuclei stock attenuates the dynamic behaviour of crystallization process.
    Additional Material: 8 Ill.
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  • 42
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Supersaturation is the driving force for crystallization from solution. For design and operation of crystallization processes, it is necessary to apply a set of criteria for the determination of appropriate or even optimum supersaturation. In this paper we present and discuss the results of our experimental and theoretical investigations on supersaturation during crystallization from solution. While the determination of the metastable zone width of the solution is frequently applied as a fast check on solution behaviour, we demonstrate that the determination of the induction period of the supersaturated solution is a useful aid in ascertaining the maximum allowable supersaturation. Theoretical considerations and experiments confirm that the induction period dependssoley on growth kinetics if secondary nucleation is the predominant mechanism. In order to avoid uncontrollable spontaneous value of between 70 and 130 μm during crystallization. Since growth kinetics turns out to be the only important system property for the determination of maximum possible supersaturation, we conclude the paper with some arguments concerning a closed representation of growth kinetics.
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  • 43
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: An airlift-loop reactor with a fluidized bed was used for the microbiological removal of a complex mixture of aromatic substances originating from coal tar process waters. A specially adapted mixed microbial culture derived from several soil and sludge samples was immobilized on fluidized sand particles and retained in a reactor at high biomas concentrations of 3 to 16 g dry matter per liter, depending on the COD-load. In a two-stage pilot plant, those aromatic substances which passed through the first stage either unaltered or only partially oxidized were effectively eliminated by the immobilized biomass in the second stage. Whereas most of the waste water components such as phenols and quinoline were already degraded by a conventional activated sludge system in the first stage, the majority of nitrogen-containing aromatic bases could be sufficiently eliminated with specially adapted micro-organisms in the second stage. Although the COD-feed load was increased to 12 and 15 kg m-3 d-1 in the first and second stages, respectively, it was removed to the extent of 87% on the average with an overall residence time varying between 11.5 and 29 h.
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  • 44
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    Weinheim : Wiley-Blackwell
    Chemical Engineering & Technology - CET 13 (1990), S. 86-96 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The first part of this paper presents a relationship for the minimum velocity of rotating installations for foam breaking. The derivation is based on equilibrium of inertia and surface forces. Inertia forces occur during the acceleration of foam bubbles and act mainly at the plateau borders. High and definite acceleration can be obtained with a deformer composed of a rotor and a stator. The surface force is due to the dynamic surface tension because surface-active solutions react to a rapid change in surface area by altering their surface tension. The theoretical relationship is compared with experimental results of minimum velocities needed to break foams produced from aqueous solutions of detergents. The equation presented here explains why measured minimum velocities often range between 10 and 20 m/s. The second part of the paper deals with condensation of continuously generated foam in a closed system. In the process of condensation, foam is not completely separated into liquid and gas phase but turns into foam with small bubbles and high density. The collapse of this condensed foam must be considered for the control of persistent foams in a closed system. The collapse of foams made of aqueous solutions of different surface-active agents has been investigated. Different highly surface-active agents show small variations in times of coalescence. A relationship for the lifetime is given, which is based on laminar flow along plateau borders. Recommendations are made with respect to the geometry of the foam breaker, scale-up and operating variables such as rotational speed of the foam breaker and gas flow rate.
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  • 45
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    Chemical Engineering & Technology - CET 13 (1990), S. 349-356 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Owing to imperfect mixing, the theoretical prediction of CSD for an MSMPR crystallizer deviates from the experimental results. In the present work, different modelling approaches were adopted to account for incomplete mixing in DTB and FC crystallizers. For DTB crystallizers, compartmental model, based on an earlier work of Nyvlt et al. has been proposed. For FC crystallizers, a mixed model comprising perfectly mixed and plug flow regimes has been put forward. This is based on the tracer response studies reported by de Jong. Predicted results were compared with experimental data of Bennett and van Buren for continuous urea crystallizers.
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  • 46
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Compared to chemical reactors, there are additional requirements to be considered when selecting and designing a bioreactor. The cultivated organisms and most of the desired products are to a greater or lesser extent sensitive to temperature, pH and Shear stress. Furthermore, sterilization often plays an important role in maintaining a monoseptic process. Many design procedures for chemical reactors can be applied but requirements which are relevant to the biological system are sometimes decisive. Consequently, it is useful to first consider the essential features of the organisms with respect to the selection and design of bioreactors. Attention must be paid to the fermentation medium because its flow behaviour can range from slightly viscous and Newtonian to highly viscous, non-Newtonian. Many papers deal with low viscosity fermentation broths [1-5]. However, little is known about the design of bioreactors for highly viscous non-Newtonian liquids. Fundamentals for the design of bioreactors are presented. It has been attempted to apply theoretical equations suitable for both, low viscosity Newtonian and high viscosity non-Newtonian fermentation broths. Apart from the calculation procedure for the OTR-values, the difference between global and local values within bioreactor is demonstrated by means of velocity and shear stress profiles. Special requirements for bioreactors such as prevention of excessive foaming, shear sensitivity of micro-organisms and cell-lines and effective sterilization are also discussed.
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  • 47
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    Weinheim : Wiley-Blackwell
    Chemical Engineering & Technology - CET 13 (1990), S. 392-397 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A Monte Carlo simulation scheme is proposed for transient crystal size distribution in a continuous crystallizer. The suggested scheme can taken into account dispersion effects of growth rate, shape factor and birth size on crystal size distribution. This method is simple and more versatile than solution of the number balance equation or the finite-state Markov chain model. The proposed algorithm of the process has a very simple structure and can be easily implemented on a personal computer. The present contribution is extension of an earlier work of Sen Gupta and Dutta.
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  • 48
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The presented contribution reports on comprehensive hydrodynamic investigations in two pulsed sieve-plate extraction columns (PSE) on a pilot scale. The experiments were conducted with three different sieve plate geometries employing test systems recommended by EFCE, under varying pulsation conditions and throughputs. The results of the investigation add to the existing knowledge of relationships between hydrodynamic parameters, drop size, hold-up, flooding throughput and mixing and operating parameters. They also provide useful information for scale up, selection of sieve-plate geometry, most favorable operating range, and constructive design of equipment. On the basis of measurements, analytical methods are recommended for prediction of PSE hydrodynamics.
    Additional Material: 15 Ill.
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  • 49
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    Chemical Engineering & Technology - CET 13 (1990), S. 304-312 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Some properties of carboxylic acids are reviewed, with emphasis on recent experimental data, Qualified, consistent latent heat of vaporization data were developed for the series and a two-population viewpoint is suggested. The equation of state formulated by Grenzheuser [1] is also recommended as a practical tool, and its further development is urged.
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  • 50
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    Chemical Engineering & Technology - CET 13 (1990), S. 328-332 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The linear algebraic character of the formal representation of chemical species and their reactions is compared with the procedure of searching for dimensionless numbers in a set of physical quantities. A straightforward algorithm is presented to find a finite set of solutions to the relevant system of “balance equations”, the so-called minimal (or simple) solutions. At the third stage of the hierarchy thus established, “mechanisms” among reactions as well as “representations” among dimensionless group can also be defined.
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  • 51
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A heterogeneous fluid dynamic model has been developed to describe the complex flow structure of two-phase in bubble columns. The equation of continuity and momentum balances form the basis of the model. Coupling of the two phases occurs via an interaction force, deduced by a force balance around a single rising bubble. Multiphase flow mixing processes are taken into consideration by introducing turbulent viscosities of the two phases involved. The Simulation program was extended to reactive system, taking into account the mass balances of a second order gas-liquid chemical reaction as well as the different absorption/reaction regimes. The gas phase concentration profiles show pronounced axial and radial dependences, while the liquid phase can be regarded as a CSTR with respect to the liquid component. With reference to the gaseous component, which is being absorbed in the liquid phase, the degree of back mixing does not show CSTR behaviour as the influence of different absorption conditions in different axial and radial reactor positions is superposed on that of turbulent motion of the liquid carrier of the dissolved gaseous component.
    Additional Material: 13 Ill.
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  • 52
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    Weinheim : Wiley-Blackwell
    Chemical Engineering & Technology - CET 13 (1990) 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
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  • 53
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    Chemical Engineering & Technology - CET 13 (1990), S. 119-125 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A dynamic mathematical model has been developed which is suitable for thermally coupled distillation processes. An algorithm known as the equation-decoupled method was used for simulation. EPISODE software and LU decomposition method were adopted to solve the ordinary differential and algebraic equations of the model, respectively. The initial conditions, viz. a solution for the steady state of the process in dynamics simulation were obtained by means of modified Naphtali-Sandholm algorithm. Research on the dynamic behaviour of thermally coupled distillation processes was carried out on two examples. It was found, via the dynamic simulation, that a disturbance in the distribution of vapour coupled stream has a large effect on the composition of vapour side withdrawal and, similarly, for liquid coupled stream, on that of liquid side withdrawal when the fraction of side withdrawal is fixed, and a smaller effect when the quantity of side withdrawal is fixed.
    Additional Material: 6 Ill.
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  • 54
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    Weinheim : Wiley-Blackwell
    Chemical Engineering & Technology - CET 13 (1990), S. 196-202 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A Random Crystal Growth (RCG)model is proposed to predict CSD in a continuous MSMPR crystallizer when the crystals exhibit growth rate dispersion. RCG model links two well-known models of growth rate dispersion, namely the Random Fluctuation (RF) and Constant Crystal Growth (CCG) Models. Monte Carlo simulation has been employed to solve the model equations. Predicted results are compared with experimental CSD data on sucrose reported by Bennett.
    Additional Material: 3 Tab.
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  • 55
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The well-known formulae for efficiency and mean temperature difference of a heat exchanger as functions of its numbers of transfer units, or dimensionless lengths, can be written in a more compact form by introducing the auxiliary function ϕ(x) = x/(1 - e-x). The resulting new formulae show a number of advantages: They are shorter, easier to memorize, and in many cases the limiting values can be seen more directly. They may therefore contribute to easier and faster heat exchanger design, and to reduced probability of errors in the relevant calculations.
    Additional Material: 3 Ill.
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  • 56
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    Chemical Engineering & Technology - CET 13 (1990), S. 258-264 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Deasphaltization of heavy crude oils and distillation residues may reduce the metal content of these oils to such an extend that the upgrading of deasphaltized oil in a catalytic process becomes economically feasible. Experimental results of deasphaltization of Boscan crude from Venezuela, using subcritical and supercritical carbon dioxide as deasphaltizing agent, are presented. Deasphaltization and demetalling with CO2 in the supercritical state is more effective. Under favorable conditions, the deasphaltized oil contains practically no asphaltenes and the metal content is reduced by 690 wt-%. The influence of n-heptane or n-pentane addition to the crude, which lowers viscosity and promotes flocculation, is also discussed. Furthermore, a multistage deasphaltization process is more efficient than a single stage process.
    Additional Material: 14 Ill.
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  • 57
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    Chemical Engineering & Technology - CET 13 (1990), S. 277-288 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The present paper is a case study of an application of sensitivity analysis in chemical kinetics. Emphasis is laid upon chemical interpretation of sensitivity information and on identification of the most important model important model parameters. The kinetic model for reforming of C6 hydrocarbons proposed by Mobil [14] is extended to the analysis of the behavior of n-hexane conversion in an adiabatic reactor. The importance of six initial conditions (feed composition and initial temperature) is analyzed by the computation of normalized first order sensitivity gradients (y1o/y) (δyi/δy1o). The relative importance of 21 model parameters αj is estimated by the computation of normalized sensitivity gradients of the type (αj/yi) (δyi/δαj). The influence of the decisive model parameters ΔH6o and ΔH3o (activation enthalpies of benzene hydrogenation and methyl cyclopentane isomerization, respectively) as well as operating parameters is presented. The problem of uncertainly in the value of ΔH6o and its influence on the model solution is also sown. Finally, some advantages of the application of normalized gradients of the explanation of process behavior are discussed.
    Additional Material: 11 Ill.
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  • 58
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    Chemical Engineering & Technology - CET 13 (1990), S. 319-322 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A mathematical model based on experimental results is set up for a typical model reaction of hydrocarbon reforming, namely the dehydroisomerization of methyl cyclopentane. Computer simulations shows that the existing theory about the reaction path of hydrocracking reactions involving bifunctional catalysts may be only partly valid.
    Additional Material: 6 Ill.
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  • 59
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    Chemical Engineering & Technology - CET 13 (1990), S. 322-327 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Deposition of particles from gas flows on ribbons in normally expected on the front side. Collision efficiencies of ribbons are presented for this case, obtained by means of single particle trajectory computation, which is based on numerically determined flow fields in the Reynolds number range between 2 and 50 and on the potential flow model. Further, it is shown, that deposition of particles on the rear side can be caused by eddylike motion of the fluid in the wake of the ribbon. For this to occur, two conditions must be fulfilled: the free shear layer between the wake and the outer flow must be turbulent to cause lateral transfer of particles into the wake and the Stokes number may not exceed 0.5.
    Additional Material: 6 Ill.
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  • 60
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    Chemical Engineering & Technology - CET 13 (1990), S. 371-375 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A solution of 0.1 M 1,2-dichloroethane in 1 M H2SO4 was anodically converted to CO2, Cl2 and HCIO4 as the main products at smooth platinum. The current efficiency for CO2 exceeds 60% at low current densities, while HClO4 is obtained with about 20% current efficiency. Chlorinated products such as 1,2′,2-trichloroethane are formed in negligible amounts. Platinum plays a distinctive role as anode material and shows a reaction limited anodic prewave. Our experimental findings lead to a mechanism, whereby DCE is initially hydroxylated to form chloroacetaldehyde chlorohydrin which releases HCl and becomes rapidly further oxidized to monochloroacetic acid. The cleavage of the C—C bond proceeds via its anodic decarboxylation. Possible practical applications in the field of anodic water purification and in the direct electrosynthesis of vinyl chloride are discussed.
    Additional Material: 6 Ill.
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  • 61
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The collection of reactive and therefore extremely adhesive and cohesive fine particles (〈 1 μm) by means of bag filters with pulse-jet cleaning may present problems. The electron-beam dry scrubbing (EBDS) process, used to remove SO2 and Nox in a power plant of the Badenwerk AG, Karlsruhe, serves as an example. To solve the occurring problems and achieve a satisfactory filter performance, extensive know-how of process engineering is necessary. This contribution deal with the following aspects: construction of the cleaning system, selection of filter medium, precoating, and dosage of an auxiliary dust during filtration.
    Additional Material: 15 Ill.
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  • 62
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Holographic interferometry is used for the determination of surface deformation of items of equipment. The material failure which caused the surface deformation can then be identified. Because a double-pulsed laser is used to plot the hologram, non-vibration stabilized holographic equipment is necessary. Thus, non-destructive testing of equipment components is also possible during plant operation. In this report, we present the experimental results of non-destructive testing of composite materials. We examined centrifugally cast pipes and filament wound pipes, which were made from glass fibre reinforced plastic and carbon fibre reinforced graphite. As a rule, the severity of failure is characterized by the apparent perturbation of its holographically stored fringe pattern. In this report, we present the experimental results which yield the relationship between the perturbation of interference fringes and the extent of the specific types of failure. Measurement results were compared with displacements calculated by the finite element method. By using the interferogram, and with the knowledge of tension stress beneath the surface, the size of the crack can be estimated. The size of the smallest detectable flaw was clearly smaller than the critical flaw size. Thus, holographic interferometry is suitable for detecting damage to cylindrical containers.
    Additional Material: 15 Ill.
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  • 63
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: This contribution reports on the breakthrough behaviour of binary gas mixtures with ideal and non-ideal multicomponent adsorption equilibria. Investigations were carried out on mixtures CO2/C2H4 and C2H4/C2H6, both adsorbed on molecular sieve 5A (ms5A). The adsorption equilibrium of the system CO2/C2H4/ms5A may exhibit azeotropic behaviour, which subsides with decreasing active pressure (= sum of partial pressures of adsorbable components) or on raising the temperature. In contrast, the system C2H4/C2H6/ms5A maintains its ideal behaviour also at higher active pressures or lower temperatures. Attempts to calculate the non-ideal adsorption equilibrium from measured single component isotherms have failed when known models were applied. The investigation of the effect of azeotropic equilibrium on the fixed bed adsorption led to intersecting breakthrough curves of the two components. This behaviour is due to a displacement of equilibrium caused by the change in the active pressure and partial pressures, and a superposed temperature effect. This can be shown by calculating the breakthrough curves with the equilibrium model.
    Additional Material: 9 Ill.
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  • 64
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: In the first part of this contribution, a mathematical model was presented for a liquid fluidized bed using immobilized enzymes, with reversible Michaelis-Menten kinetics. This part is focused on the experimental results. The reaction kinetics of native and immobilized enzymes was determined in continuous stirred tank reactors under comparable conditions. The influence of external mass transfer was investigated in a fixed bed reactor column. The extend of pore diffusional resistance was examined in a continuous stirred tank reactor and with a numerical simulation. Hydrodynamics was measured in different reactor columns (diameter dt = 0.052 - 0.225 m; length L: 1.0-2.0m) and with a static mixer. Further, the concentration profile was determined in a fluidized bed reactor with side stream analysis for different biocatalyst samples, fluid velocities and bed heights. The simulation of experimental results indicates that they are well described by the developed model. Furthermore, the model is well suited to predicting the influence of specific parameters on the effective kinetics of the biocatalyst and the expansion of the fluidized bed.
    Additional Material: 8 Ill.
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  • 65
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    Chemical Engineering & Technology - CET 13 (1990), S. 97-101 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Laboratory-scale measurements were performed on the absorption of NO2 gas into diluted nitric acid. The concentration of NO2 gas, which represents an NO2/N2O4 equilibrium, varied from 1000 to 20000 ppm, the carrier gas being nitrogen. The concentration of nitric acid ranged from 15 to 60 mass-%. The absorption experiments were carried out in a double stirred cell, with a defined gas/liquid interface as the mass transfer area. The liquid phase was conducted periodically and the gas phase continuously. Mass flow rates were determined. The well-known film model of absorption was used for analyzing the experimental results. Only the N2O4 species was considered to pass the gas/liquid interface. The measured data yielded values of HN2O4(k D1)1/2 as well as their variation with temperature and nitric acid concentration.
    Additional Material: 5 Ill.
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  • 66
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The BF-Uhde-Mitsui Process uses active coke for SO2- and NOx-removal from flue gases in the temperature range between 100 and 190 °C, Experimental methods of thermal regeneration were applied to the evaluation of the state of the adsorbent after use in flue gas cleaning and of the parameters for disrober design. A reaction model was derived from experiments carried out in differential and back-mix reactors. The parameters were evaluated by adaptation of the model to the adsorption spectra. The model was successfully applied to the regeneration of active coke in a fluidized bed reactor.
    Additional Material: 16 Ill.
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  • 67
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    Chemical Engineering & Technology - CET 13 (1990), S. 113-118 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The hydrodynamic and mass transfer characteristics in countercurrent, cocurrent and liquid batch operations with various Newtonian liquids were studied experimentally using the same bubble column. Taking the effect of gas sparger geometries, operating variables and liquid properties into account, empirical correlations were obtained for the gas hold-up and the volumetric liquid-phase mass transfer coefficient.
    Additional Material: 8 Ill.
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  • 68
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    Chemical Engineering & Technology - CET 13 (1990), S. 125-130 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Critical temperatures and pressures have been determined experimentally for the four lowest n-alcohols, 2-propanol, 2-butanol, and 2-methyl-1-propanol, and are given in the penultimate line of Table 3. The last line of Table 3 lists the weighted mean critical pressures, with the corresponding critical temperatures obtained from he vapour pressure equation. Comparison with the corresponding data from standard reference books reveals deviations from the experimental data in some [2, 4] and incorrect critical pressure for ethanol in all five reference books quoted in Table 3. In addition, vapour pressure data were obtained for the same alcohols in the temperature range approaching the critical point. The measurements are reproduced by the simplified Clausius-Clapeyron equation with the constants and standard deviation given in Table 2.
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  • 69
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    Chemical Engineering & Technology - CET 13 (1990), S. 131-135 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The sulphur dioxide to sulphur trioxide oxidation process in a fixed bed catalytic reactor is simulated in the case of cyclic change in the direction of the reaction mixture feed. It is shown that, for transient condition, the amount of catalyst in the reactor may be substantially reduced by its partial substitution with inert material of suitable form, dimensions and thermophysical properties, at the end of the layer. This makes the direct regenerative heat transfer process in these zones controllable, producing the same conversion and overall height of the layer. The results are significant for sulphuric acid production from gases poor in sulphur dioxide.
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  • 70
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    Chemical Engineering & Technology - CET 13 (1990), S. 136-143 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: For the dimensioning of condensers in film condensation, the heat transfer coefficient between film surface and cooled tube wall must be known. Generally, Nusselt equations are used which have been verified by experiments. When there is no significant gas flow, a large number of equations correlate the experimental. data very well. The description of heat transfer enhancement by a significant gas flow is not sufficiently covered by the available literature. For film wise condensation in a vertical tube, a calculation method is presented which reproduces this phenomenon characterized by the interfacial shear stress at the film surface. This method is based on the assumption that, in the proximity of gas flow, the condensation process also affects the interfacial shear stress. A comparison with known experimental local Nusselt numbers showed a good agreement with water as the fluid. For test fluid MWA, which was used by Blangetti, the measured values show only a moderate agreement with theoretical calculations. Possibly, this is related to entertainment which occurred during measurements at film Reynolds numbers of over 80.
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  • 71
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    Chemical Engineering & Technology - CET 13 (1990), S. 150-156 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: An experimental set-up is presented for the measurement of steady-state reaction rates in the liquid phase methyl tertiary butyl ether (MTBE) synthesis from isobutene and methanol using ion exchange resin as catalyst. This apparatus was used for a separate investigation of the main side reaction, i.e., the formation of isobutene dimers (DIB), in the temperature range between 60 and 90°C. The reaction catalyzed by Amberlyst 15 (A15) showed no steady-state behaviour, but the catalytic activity declined at a rate dependent on the reaction conditions. Time constants for activity loss were determined in the range from 3.5 to 30 h. The deactivated A15 catalyst could be regenerated through MTBE synthesis experiment. Deactivation is assumed to be caused by blocking of the microparticle gel phase by higher isobutene oligomers. The DIB formation, using 1-butene as solvent, was of 2nd order with respect to isobutene and showed an apparent activation energy of about 40 kJ/mol.
    Additional Material: 8 Ill.
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  • 72
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    Chemical Engineering & Technology - CET 13 (1990), S. 161-171 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Knowledge of modelling and computer simulation is an essential prerequisite for type design and operation of packed bed systems. Unfortunately, the existing models are based on a number of weak assumptions of which plug flow can be considered as a common deficiency. Such a simplification would inevitably have a noticeable bearing on the accuracy of the final design and consequently calls for the development of a coherent mathematical description of the packed bed systems so that reliable design information can be explored. A two-dimensional heterogeneous transient model has been developed which allows for the radial variations of velocity and void age. The model equations have been solved using numerical approximation. The simulated results reveal significant differences between the present refined data and those established from existing plug flow models.
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  • 73
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Many experimental studies reveal that suspended solids considerably alter the coalescence behaviour and hydrodynamic functions of wo-phase flow. But no systematic efforts have yet been undertaken to separate the effects of different particle properties on local gas hold-up, bubble size and interfacial area gas/liquid. The aim of this paper is to present the local values of these parameters in three-phase fluidized beds of different solids, using miniaturized optical fiber and conductivity needle probes. It is shown that particle concentration, size and, in particular, density are decisive for the change in coalescence behaviour. Ranges of normal (ϱS 〉 ϱL) and inverse fluidization (ϱS 〈 ϱL) must be distinguished and the flow regime also exerts a strong influence on the interactions between the dispersed phases, the transition point itself being a function of particle properties can be observed, This effect is evaluated for different column diameters, between 0.1 and 0.3 m.
    Additional Material: 13 Ill.
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  • 74
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Aerated emulsions are gaining significance in fermentation as well as in inorganic and organic chemistry. In these processes, liquid-liquid mass transfer can be the limiting step. Therefore, the effect of gassing rate on droplet size was investigated as a function of dispersed liquid phase concentration and power input in different vessels. At high power inputs, the droplet size decreased. With increasing dispersed phase concentration and gassing rate, the droplet size increased and its dependence on power input subsided.
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  • 75
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    Chemical Engineering & Technology - CET 13 (1990), S. 214-220 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Experimental investigations of thermal bulk polymerization of styrene in pilot plants of different sizes have been performed. Each pilot plant is composed of a tubular recycle reactor, connected in series with a tubular reactor, both completely filled with Sulzer motionless mixers. Kinetic, reactor and viscosity models have been verified in a wide range of styrene conversions (up to 96%) temperatures (up to 210 °C) and polystyrene molar masses (up to 360 000). Scale-up studies were carried out which confirmed that multitubular reactors of special design can be applied for industrial polymerization process.
    Additional Material: 11 Ill.
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  • 76
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Warm concentrated industrial wastewaters are preferably treated in an anaerobic reactor for reasons of energy generation and low surplus sludge production. Problems to be solved in the practical application concern a low growth rate of the micro-organisms, their low settling rate, process instability and the need for after treatment of the noxious anaerobic effluent which often contains NH4+ and HS-. The use of biomass immobilized on small suspended carriers (〈 0.5 mm) has proven to be a suitable means to overcome most of these problems. Results are presented on pilot and full-scale pretreatment of industrial wastewater in an anaerobic 2-state fluidized bed reactor for CH4-production and laboratory and pilot scale post-treatment of the anaerobic effluent, which contains NH4+ and HS- in an aerobic air-lift suspension reactor for the production of NO3- and SO42-.
    Additional Material: 13 Ill.
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  • 77
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The production of dioxins/furans during waste incineration, and particularly the development of measures for minimizing the amount of generated pollutants, continue to command a considerable scientific as well public interest. Experiments are reported which were performed at the TAMARA municipal solid waste pilot incineration, erected on the premises of the karlsruhe Nuclear Research Centre. These experiments show that the solid waste mass flow rate and moisture content influence the dioxin/furan formation, Good removal efficiencies of dioxins/furans have been In wet cleaning. Hydrogen peroxide added to the crude gas is an interesting “killer” reagent for dioxins/furans.
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  • 78
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    Chemical Engineering & Technology - CET 13 (1990), S. 251-258 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Regeneration of diesel particulate filters can be accomplished by complete combustion of a collected particulate. A reactor has been developed for study of the regeneration in the presence of catalysts, additives and ignition aids. This reactor allows an accurate measurement of soot ignition temperatures and a kinetic study of soot oxidation with an undisturbed soot layer and under a defined gas composition. Results of various investigations carried out with this reactor are presented.
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  • 79
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    Chemical Engineering & Technology - CET 13 (1990), S. 273-277 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The majority of the fluidized-bed reactor models are models are rooted in the tacit assumption that transport between the bubble, cloud, and emulsion phases occurs in series with chemical reaction. A more realistic model that anticipates simultaneous transport and reaction is presented in terms of a fluid-bed effectiveness factor which embraces the limits between chemical and mass transport control. Analysis of the predictive capacity of this model vis-a-vis the Kunii-Levenspiel model reveals signal differences in chemical conversion.
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  • 80
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    Chemical Engineering & Technology - CET 13 (1990), S. 384-392 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Simultaneous measurements of power consumption P and heat transfer coefficient α for a jacketed, baffled, agitated vessel of diameter D = 0.45 m, equipped with a conical turbine, were carried out. The following geometric parameters of the agitator were tested: diameter d, blade width b and number Z, and distance from the bottom of the vessel to the lower edge of the blade h. The results of these investigations were generalized mathematically. On the basis of optimization, the best geometric parameters with respect to heat transfer are proposed for the conical turbine agitator.
    Additional Material: 11 Ill.
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  • 81
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    Chemical Engineering & Technology - CET 13 (1990), S. 422-425 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The Markov process approach, as used in the modelling of particle residence time distribution in a flow system of interlinked compartments, has been compared with the deterministic model of a complex reaction system of the first order. In the latter model, interfacial reactions take place between flowing phases, corresponding to the compartments in the stochastic model. It has been demonstrated that the two approaches are equivalent. A direct method of calculating the higher moments of the residence time distribution has been verified.
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  • 82
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    Chemical Engineering & Technology - CET 13 (1990), S. 426-431 
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A general model is proposed to predict the crystal size distribution from multistage MSMPR Crystallizers taking into account shape factor, birth size and growth rate dispersions. Two cases, namely nucleation in the first crystallizer and the same process in all crystallizers have been considered. The developed equations can be solved easily by the Monte Carlo technique. The model represents an extension of the earlier work of Sen Gupta and Dutta.
    Additional Material: 3 Ill.
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  • 83
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    Weinheim : Wiley-Blackwell
    Chemie Ingenieur Technik - CIT 31 (1959) 
    ISSN: 0009-286X
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
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  • 84
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    Chemie Ingenieur Technik - CIT 31 (1959), S. 18-20 
    ISSN: 0009-286X
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: In einer thermischen Spaltanlage wird aus methan-haltigem Koksofengas Synthesegas erzeugt. Hierbei fällt Ruß an. Aus dem wasserdamfhaltigen Spaltgas wird er mit Schlauchfiltern abgeschiden. Das Gas is dadurch maschinenrein, der Ruß wird in verkaufsfähiger Form gewonnen. Über Betriebsversuche Gas ist dadurch maschinenrein, der Ruß wird in verkaufsfähiger Form gewonnen. Über Betriebsversuche Gas ist dadurch maschinenrein, der Ruß wird in verkaufsfähiger Form gewonnen. über Betriebsversuche mit verschiedenen Filtersystemen wird berichtet.
    Additional Material: 6 Ill.
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  • 85
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    Chemie Ingenieur Technik - CIT 31 (1959), S. 1-11 
    ISSN: 0009-286X
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Reaktionstechnische Berechungen gewinnen eine immer größere Bedeutung für die Praxis. Die Schwierigkeiten, die dabei auftreten, Können bei der Beschaffung der Ausgangsdaten, beim mathematischen Ansatz oder bei der numerischen Rechnung liegen. Die modernen elektronischen Rechenmaschinen ermöglichen es heute, sehr umfangreiche und komplizierte Berechnungen in kurzer Zeit auzuführen, so daß der große Umfang mancher reaktionstechnischer Berechnungen kein Hindernis mehr darstellt. Die Genauigkeit der Ausgangsdaten und die Gültigkeitsgrenzen des mathematischen Ansatzes müssen aber bei jedem speziellen Problem sorgfältig diskutiert werden. An Hand von Beispielen für thermodynamische und kinetische Berechnungen und der Berechnung eines optimalen Reaktionsapparates werden diese Geischtspunkte diskutiert.
    Additional Material: 11 Ill.
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  • 86
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    Chemie Ingenieur Technik - CIT 31 (1959), S. 12-17 
    ISSN: 0009-286X
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Es gibt - über die ganze Welt verteilt - nur etwa zehntausend lngenieure und Physiker, die sich mit der Erforschung extrem schneller Vorgänge befassen. Alle Zwei Jahre versammeln sich einige Hundert von ihnen, um in einer internationalen Tagung neue Fors chungsergebnisse, auf apparativem Gebiet wie auch auf dem Sektor der Anwenungen, auszutauschen. Die IV. Tagung dieser Art, die vom 22. bis 26. September 1958 in Köln stattfand, war deshalb besonders interessant, weil zum ersten Mal Forscher ausder Sowjetunion, wo die Kurzzeitphotographie im Zusammenhang mit der Entwicklung von Raketen, nuklearen Waffen und Fusionsreaktoren beträchtlich vorangetrieben wurde, ihre neuen Geräte vorstellten und die westlichen Kollegen mit den von ihnen erzielten Leistungen überraschten.
    Additional Material: 6 Ill.
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  • 87
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    Chemie Ingenieur Technik - CIT 31 (1959), S. 20-21 
    ISSN: 0009-286X
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Bei der Kreislaufmahlung und der später entwickelten Umlaufhomogenisierung wird dem Zerkleinerungs- bzw. Mischvorgang ein Trennvorgang nachgeschaltet, wodurch eine Energieersparnis erreicht wird.
    Additional Material: 3 Ill.
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  • 88
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    Chemie Ingenieur Technik - CIT 31 (1959), S. 22-30 
    ISSN: 0009-286X
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Die in einer früheren Arbeit angestellten Optimalbetrachtungen über die Anreicherung von schwerem Wasser in Heiß-Kalt-Kolonnen werden auf eine aus mehreren Heiß-Kalt-Kolonnenpaaren bestehende Trennkaskade ausgedehnt. Außerdem werden die mit der Erhöhung der Deuterium-Ausbeute durch ein als Abstreifsystem wirkendes HeißKalt-Kolonnenpaar und die mit dem Einsatz einer Übertragungskolonne zusammenhängenden Fragen diskutiert.
    Additional Material: 9 Ill.
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  • 89
    ISSN: 0009-286X
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Es wird das in der industriellen Anlage des Commissariat francais pour I'Energie Atomique in Marcoule angewandte Verfahren zur Abtrennung des Plutoniums aus den bestrahlten Uran-Brennstoffelementen sowie die Reinigung des Urans und Plutoniums und die Konzentrierung der Spaltprodukte beschrieben.
    Additional Material: 2 Ill.
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  • 90
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    Chemie Ingenieur Technik - CIT 31 (1959), S. 33-35 
    ISSN: 0009-286X
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Die Schwächung von β-Strahlen ist abhängig vom Flächengewicht und vom Verhältnis Ordnungszahl Z/Atomgewicht A des durchstrahlten Mediums. Dies ermöglicht die Messung des Flächengewichts bei konstantem Z/A-Verhältnis, bzw. des Z/A-Verhältnisses bei konstantem Flächengewicht. Die zweite Möglichkeit ist die Grundlage der C/H-Messung in aromatischen Kohlenwasserstoffen; dabei wird der Strahler fest mit einem Schwimmer verbunden, dessen Auftrieb in Abhängigkeit von der Dichte des flüssigen Mediums automatisch ein konstantes Flächengewicht über dem Strahler herstellt, so daß das Meßergebnis nur vom C/H-Verhältnis abhängig ist. In flüssigen Kohlenwasserstoffen wird auf diese Weise ein kontinuierlich arbeitender Nachweis des Wasserstoff-Gewichtanteils auf ± 0,16% erreicht.
    Additional Material: 3 Ill.
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  • 91
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    Chemie Ingenieur Technik - CIT 31 (1959), S. 36-43 
    ISSN: 0009-286X
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Schwere Blechpackungen, Trommeln und Fässer, werden in Deutschland vorwiegend von der chemischen Industrie als Verpackungsmittel für ihre mannigfachen Erzeugnisse verwendet. Der Oberflächenschutz dieser Behälter, die im Inlandverkehr vielfach als Leihgebinde laufen, ist für die Wirtschaft ein ernstes Problem, da jährlich eine beträchtliche Zahl von Behältern durch Korrosion unbrauchbar wird, und infolgedessen immer wieder erhebliche Beträge für die Neubeschaffung aufgewendet werden müssen. Im folgendessen immer wieder erhebliche Beträge für die Maßnahmen besprochen, mit denen man einen möglichst befriedigenden Oberflächenschutz dieser Gebinde erreichen kann; dabei wird auf neuere Entwicklungen in den USA besonders eingegangen.
    Additional Material: 4 Ill.
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  • 92
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    Chemie Ingenieur Technik - CIT 31 (1959), S. 54-58 
    ISSN: 0009-286X
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 1 Ill.
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  • 93
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    Chemie Ingenieur Technik - CIT 31 (1959), S. 59-62 
    ISSN: 0009-286X
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
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  • 94
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    Chemie Ingenieur Technik - CIT 31 (1959), S. 50-54 
    ISSN: 0009-286X
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Einige von Tigerschiöld und Rumpf angegebene Formeln für die Festigkeit von Pellets auf Grund von Kapillarkräften oder Salzbrücken werden an Preßlingen aus Tonerde nachgeprüft. Die Festigkeit ergibt sich als proportional zur Oberflächenspannug der Pelletisierungsflüssigkeit und umgekehrt proportional zur Korngröße, übereinstimmend mit der Theorie. Salzablagerungen findet man bevorzugt an der Oberfläche der Pellets, weil dort die Verdunstung am stärksten ist.
    Additional Material: 11 Ill.
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  • 95
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    Chemie Ingenieur Technik - CIT 31 (1959), S. 43-49 
    ISSN: 0009-286X
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Die Wirksamkeit elektrischer Entstaubungsanlagen wird durch das Rücksprühen (Rückionisation) bei der Abscheidung von Stäben mit extrem hohem elektrischem Widerstand herabgesetzt. Das Rücksprühen an Schichten elektrisch niedergeschlagenen Staubes bei 150 °C an Eisensulfat, Eisenoxyd, Zinkoxyd, Steinkohle, Braunkohle, Zement, Magnesiumoxyd und Flugasche wurde untersucht. Nach den Ergebnissen wird die Rückionisation durch hohen Staubwiderstand, hohe Stromdichte und geringe Schichtdicke des niedergeschlagenen Staubes begünstigt. Besonders kräftiges Rücksprühen ist z. B. an Schichten von etwa 0,2 mm Dicke von Stäuben, deren spezifischer Widerstand größer als 2 · 1012 Ohm cm ist, zu beobachten.
    Additional Material: 18 Ill.
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  • 96
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    Chemie Ingenieur Technik - CIT 31 (1959), S. 62-62 
    ISSN: 0009-286X
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
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  • 97
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    Chemie Ingenieur Technik - CIT 31 (1959), S. 65-66 
    ISSN: 0009-286X
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
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  • 98
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    Chemie Ingenieur Technik - CIT 31 (1959), S. 63-64 
    ISSN: 0009-286X
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
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  • 99
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    Chemie Ingenieur Technik - CIT 31 (1959), S. 67-67 
    ISSN: 0009-286X
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
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  • 100
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    Chemie Ingenieur Technik - CIT 31 (1959), S. 68-72 
    ISSN: 0009-286X
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
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