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  • 1
    Electronic Resource
    Electronic Resource
    Zur Komplexbildung von Proteinen mit Cu2+-Ionen im sauren Milieu (1975)
    Springer
    European food research and technology 159 (1975), S. 73-77 
    Details
    ISSN: 1438-2385
    Source: Springer Online Journal Archives 1860-2000
    Topics: Process Engineering, Biotechnology, Nutrition Technology
    Description / Table of Contents: Zusammenfassung Zur Klärung des Einflusses von Kupfersulfat-Zulagen auf die Proteinverdaulichkeit wurden Versuche zur Komplexbildung von Proteinen Mit Cu2+-Ionen im sauren pH-Bereich (pH 2,2) durchgeführt. 300 mg isoliertes Sojaprotein bzw. Pepsin wurden mit 10 μmol (2,49 mg) CuSO4 · 5H2O versetzt und nach der Reaktion gegen niedermolekulare Komplexbildner mit steigender Affinität zu Cu2+-Ionen dialysiert. Bei den Versuchen mit Sojaprotein dialysierten Cu9+-Ionen zum größten Teil (97% des Gesamt-Cu-Gehaltes) bereits ohne Zusatz eines Komplexbildners, bei den Versuchen mit Pepsin edoch weniger (83% des Gesamt-Cu-Gehaltes). Die verbleibenden Cu2+-Ionen des Pepsins konnten erst durch die Komplexbildner Alanin und Ammonium-tetramnethylendithiocarbamat entfernt werden. Im sauren pH-Bereich bilden also Cu2+-Ionen nur mit Pepsin, nicht jedoch mit Sojaprotein Komplexe. Dieser Effekt wird auf den sehr niedrigen isoelektrischen Punkt des Pepsins zurückgeführt. Bei der Bestimmung der in den nativen Proteinen enthaltenen Eisen-, Nickel- und Zinkmengen zeigte sich, daß bei pH 2,2 Eisen und Nickel stärker an Pepsin gebunden sind als an Sojaprotein; Zink war an beiden Proteinen nur schwach gebunden.
    Notes: Summary In order to determine the influence of copper additives on the protein digestibility, the complex formation of proteins with Cu ions under acidic conditions (pH = 2.2) was investigated. Isolated soja-protein (300 mg) resp. pepsin was mixed with 10 μmol (2.49 mg) CuSO4 · 51120 and dialysed against low molecular complexing agents with increasing affinity towards copper ions. The experiments with soja-protein showed, that most of the Cu ions dialysed (97% of total Cu2+ content) without any addition of complexing agents, pepsin, however, had a lower percentage (83% of total Cu2+ content). The remaining copper ions in pepsin could only be removed by alanin and ammonium-tetramethylendithiocarbamate. Therefore it is concluded, that in the acidic range Cu ions only form complexes with pepsin, but not with soja-protein. This effect is due to the very low isoelectric point of pepsin. The determination of iron, nickel, and zinc in native proteins revealed, that at pH = 2.2 iron and nickel are stronger linked to pepsin than to Soja-protein; only zinc was loosely bound to both proteins.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01135780
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  • 2
    Electronic Resource
    Electronic Resource
    Zur gaschromatographischen bestimmung von captafol in weizen-pflanzen nach reinigung mit der gelpermeationschromatographie (1981)
    Springer
    European food research and technology 173 (1981), S. 368-371 
    Details
    ISSN: 1438-2385
    Source: Springer Online Journal Archives 1860-2000
    Topics: Process Engineering, Biotechnology, Nutrition Technology
    Description / Table of Contents: Zusammenfassung Nach der vorliegenden Methode können Rückstände des Fungicides Captafol in Weizen-Pflanzen,-Körnern und -Stroh bestimmt werden. Dazu wird Captafol aus dem gut zerkleinerten Probematerial mit Toluol extrahiert. Die Extrakte werden durch eine Kieselgelsäule vorgereinigt. Die noch vorhandenen Pflanzeninhaltsstoffe werden mit der Gelpermeationschromatographie (GPC) entfernt. In dem gereinigten Extrakt kann Captafol störungsfrei bestimmt werden. Für die gaschromatographische Bestimmung von Captafol wird die Verwendung der Trennsäule 3% XE-60 auf Gaschrom Q vorgeschlagen. Zulagen von 0,50 mg Captafol/kg Probematerial werden aus Weizen-Pflanzen, -Körnern und -Stroh im Durchschnitt zu 99% wiedergefunden. Für geringere Zulagen von 0,10–0,40 mg Captafol/kg Weizen-Körner wurde eine durchschnittliche Wiederfmdung von 108% bestimmt. Die Nachweisgrenze der Methode liegt bei 0,25 μg bzw. 0,0125 mg/kg.
    Notes: Summary The described method can be used for the determination of residues from the fungicide captafol in plants, kernels and straw of wheat. For this purpose captafol is extracted from the carefully comminuted sample material with toluene. The extracts are purified on a silica-gel column. Captafol is separated from other plant ingredients by Gel-Permeation Chromatography (GPC). In the purified extracts captafol can be determined without interferences. The use of the column, 3% XE-60 on Gaschrom Q, is proposed for the gas-chromatographic separation and determination of captafol. For wheat-plants, -kernels and -straw the mean recovery of 0,50 mg captafol/ kg sample material was 99%. The mean recovery of added captafol to wheat kernels at a level of 0,10–0,40 mg/kg was 108%. This method is sensitive down to 0,25 μg respectively 0,0125 mg/kg.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01042058
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  • 3
    Electronic Resource
    Electronic Resource
    Quark structure and weak decays of heavy mesons (1994)
    Springer
    The European physical journal 63 (1994), S. 121-130 
    Details
    ISSN: 1434-6052
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract We investigate the quark structure ofD andB mesons in the framework of a constituent quark model. To this end, we assume a scalar confining and a one gluon exchange (OGE) potential. The parameters of the model are adopted to reproduce the meson mass spectrum. From a fit to ARGUS and CLEO data onB→D * lv semileptonic decay we find for the Cabbibo Kobayashi Maskawa matrix elementV cb =(0.036±0.003) (1.32 ps/τ B )1/2. We compare our form factors to the pole dominance hypothesis and the heavy quark limit. For non-leptonic decays we utilize factorization and forB→D (*) X decays we finda 1=0.96±0.05, anda 2=0.31±0.03.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01577551
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  • 4
    Electronic Resource
    Electronic Resource
    Influence of pulp density and bioreactor design on microbial desulphurization of coal (1986)
    Springer
    Applied microbiology and biotechnology 24 (1986), S. 342-346 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Summary Pyrite was microbiologically removed by Thiobacillus ferrooxidans in pure and mixed cultures from German bituminous coal at 10% pulp density with maximum pyrite oxidation rate of 350 mg pyritic S/l per day. However, at pulp densities above 20% bacterial growth and consequently pyrite oxidation were completely prevented both in a conventional airlift reactor and in a stirred-tank reactor. Modifying the airlift reactor by adapting a conical bottom part, bacterial growth and pyrite oxidation could be achieved even at 30% pulp density, resulting in a pyrite removal of more than 90% at a pyrite oxidation rate of 230 mg pyritic S/l per day.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00257061
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  • 5
    Electronic Resource
    Electronic Resource
    Degradation of phenanthrene, fluorene and fluoranthene by pure bacterial cultures (1990)
    Springer
    Applied microbiology and biotechnology 32 (1990), S. 479-484 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Summary Bacterial mixed cultures able to degrade the polycyclic aromatic hydrocarbons (PAH) phenanthrene, fluorene and fluoranthene, were obtained from soil using conventional enrichment techniques. From these mixed cultures three pure strains were isolated:Pseudomonas paucimobilis degrading phenanthrene;P. vesicularis degrading fluorene andAlcaligenes denitrificans degrading fluoranthene. The maximum rates of PAH degradation ranged from 1.0 mg phenanthrene/ml per day to 0.3 mg fluoranthene/ml per day at doubling times of 12 h to 35 h for growth on PAH as sole carbon source. The protein yield during PAH degradation was about 0.25 mg/mg C for all strains. Maximum PAH oxidation rates and optimum specific bacterial growth were obtained near pH 7.0 and 30°C. After growth entered the stationary phase, no dead end-products of PAH degradation could be detected in the culture fluid.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00903787
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  • 6
    Electronic Resource
    Electronic Resource
    Neovascularization in the human heart is associated with expression of VEGF-A and its receptors Flt-1 (VEGFR-1) and KDR (VEGFR-2). Results from cardiomyopexy in ischemic cardiomyopathy (1999)
    Springer
    Angiogenesis 3 (1999), S. 345-351 
    Details
    ISSN: 1573-7209
    Keywords: cardiomyopexy ; indirect myocardial revascularization ; immunohistochemistry ; KDR ; vascular endothelial growth factor-A (VEGF-A)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Cardiomyopexy is a novel means of revascularization in end-stage ischemic heart disease leading to neovascularization and increased perfusion of the damaged heart. So far, the mediators of this process have not yet been identified. However, among others, vascular endothelial growth factor-A (VEGF-A) is a strong candidate for inducing this process. We have performed cardiomyopexy in humans by transplanting a flap of the musculus latissimus dorsi onto the epicardium. One of the patients died 7 weeks after cardiomyopexy due to a septic process unrelated to the underlying cardiac disease. Tissue specimen from the transplanted muscle flap, from the myocardium and from the native musculus latissimus dorsi were analysed by histological and immunohistochemical methods. The transplanted muscle appeared severely degenerated and showed no immunoreactivity for von Willebrandt factor (vWF) and for VEGF-A nor for its receptors KDR and Flt-1. However, a granulation zone had developed next to the transplanted muscle enriched with monocytes and macrophages which is characterized by a network of capillaries reaching into the ischemic myocardium and providing evidence for strong induction of angiogenesis. This process is accompanied by the abundance of VEGF-A expression in the endothelial layer of vessels. In parallel, VEGF-receptor KDR is present in capillaries passing into the subepicardial region supporting the idea of VEGF-A-induced angiogenesis. The spatial expression pattern of VEGF-A and KDR suggests VEGF-A to be a promotor of angiogenesis leading to indirect myocardial revascularization.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1026585900398
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  • 7
    Electronic Resource
    Electronic Resource
    Microbial removal of pyrite from coal using a percolation bioreactor (1987)
    Springer
    Biotechnology letters 9 (1987), S. 19-24 
    Details
    ISSN: 1573-6776
    Source: Springer Online Journal Archives 1860-2000
    Topics: Process Engineering, Biotechnology, Nutrition Technology
    Notes: Summary To compare the suspension and the percolation process system for the microbial desulphurization of coal the microbial pyrite oxidation in coal during storage in dumps was investigated in laboratory experiments with Thiobacillus ferrooxidans using a percolation bioreactor and resulted in a removal of 75% of pyrite within 70 days. In the initial desulphurization phase 450 mg pyritic-S/kg coal per day were oxidized at maximum rate, while the overall rate was determined to 130 mg pyritic-S/kg coal per day. During the desulphurization the mean particle size of the coal was reduced from 0.55 mm to 0.175 mm. As shown by microscopy and elemental analyses of the coal the pyrite was completely removed from small coal particles, whereas parts of it remained in the core of the greater particles.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01043386
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  • 8
    Electronic Resource
    Electronic Resource
    Zur Analytik von Chlorkohlenwasserstoffen in Zwiebeln nach Reinigung mit tier Gelpermeationschromatographie (1981)
    Springer
    European food research and technology 173 (1981), S. 275-278 
    Details
    ISSN: 1438-2385
    Source: Springer Online Journal Archives 1860-2000
    Topics: Process Engineering, Biotechnology, Nutrition Technology
    Description / Table of Contents: Zusammenfassung Zur quantitativen Bestimmung von Chlorkohlenwasserstoffen in Zwiebeln wurde die mit Aceton erhaltenen Zwiebel-Extrakte mit einem Gelpermeationschromatographen gereinigt, tier mit einer Nachsäule versehen war. Diese Säule enthielt 3,5 g Füllmaterial, das aus 94% Florisil, 3% Silbernitrat und 3% Wasser bestand. Das Silbernitrat wurde in einer dünnen Schicht auf die Florisilkörner aufgetragen. In den gereinigten Zwiebel-Extrakten können Chlorkohlenwasserstoffe bestimmt werden. Von 15 Chlorkohlenwasserstoffen wurden bei Zulageversuchen im Durchschnitt 96% wiedergefunden.
    Notes: Summary A method is described to purify onion extracts for the quantitative determination of organochlorine pesticides of onions by Gel-Permeation Chromatography (GPC) in combination with aftercolumn. This column is filled with 3,5 g total material, composed of 94% Florisil, 3 % silver nitrate and 3% water. The silver nitrate must be coated into the Florisil granules a thin layer. The organochlorine pesticides can be determined in the purified onion-extracts. The recoveries of 15 organochlorine pesticides averaged 96%.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01042580
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  • 9
    Electronic Resource
    Electronic Resource
    Microbial desulphurization of coal - development and application of a slurry reactorPaper presented at the “Jahrestreffen der Verfahrensingenieure”, 17. to 19. September 1986 in Strasbourg (1987)
    Weinheim : Wiley-Blackwell
    Chemical Engineering & Technology - CET 10 (1987), S. 173-179 
    Details
    ISSN: 0930-7516
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Microbial desulphurization of coal by pyrite oxidizing enrichment cultures containing predominantly Thiobacillus ferrooxidans was performed in an air-agitated slurry reactor, 20 l in volume. A model of microbiological and chemical reactions, occurring at various points within the coal, was set up taking into account the pore structure of the coal. The influence of parameters relevant to industrial processes, such as superficial gas velocity, particle size, initial pyrite concentration, and slurry density of the coal, on the conversion of pyrite was examined. Variation of the superficial gas velocity in the range of 0.01 to 0.04 m/s confirmed that the reaction is not controlled by oxygen transfer from gaseous to liquid phase. The rate of pyrite oxidation depends mainly on the accessibility of pyrite to micro-organisms which is determined by the particle size of the coal as well as the distribution of pyrite crystals in the coal matrix. The accessibility of pyrite to the micro-organisms is described by the ratio of effective to maximum microbial activity, measured as oxygen consumption. Starting with higher initial concentration of pyrite in the coal increases the oxidation rate, according to first order kinetics. Enhanced slurry densities lead to a decrease of pyrite conversion, in spite of higher pyrite concentration. The maximum pyrite oxidation rate was measured at 15% (v/v) slurry density and 25°C as 1800 mg Spyr/kg coal per day, or 360 mg Spyr/l reactor volume per day.
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/ceat.270100122
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  • 10
    Electronic Resource
    Electronic Resource
    Empirisches Inkrementsystem für Methylgruppensignale sowie Ringstrombeeinflussung der Protonen-NMR-Spektren methylsubstituierter Biphenylderivate (1984)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 117 (1984), S. 895-903 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Empirical Increment System for Methyl Group Signals and Ringcurrent Effects on Proton NMR Spectra of Methyl-substituted Biphenyls36 methyl group NMR signals of 18 methyl-substituted biphenyl derivates have been analyzed by multiple linear regression analysis to derive 4,4′- and 2,2′-position substitution constants. The influence of the torsional angle Φ on the signals of o-methyl groups increases from -0.095, -0.284, -0.345 to -0.377 ppm for Φ = 58°, 77.5°, 85°, and 90°. These values are in good agreement with the theoretical ringcurrent model of Johnson and Bovey.
    Notes: Von 18 methylsubstituierten Biphenylderivaten werden 36 Methylgruppen-NMR-Signale durch multiple lineare Regressionsanalyse auf 4,4′- und 2,2′-Positions-Substituentenkonstanten analysiert. Der Einfluß des Verdrillungswinkels Φ auf die o-Methylgruppensignale steigt von -0.095, -0.284, -0.345 auf -0.37 ppm für Φ = 58°, 77.5°, 85° und 90°. Diese Werte werden am besten durch das theoretische Ringstrommodell von Johnson und Bovey wiedergegeben.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19841170304
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