Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Tandem Inter [4 + 2]/Intra [3 + 2] Cycloadditions. 6. The Bridged Mode (1995)
    s.l. : American Chemical Society
    Journal of the American Chemical Society 117 (1995), S. 2100-2101 
    Details
    ISSN: 1520-5126
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ja00112a027
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Nucleophilic substitutions of 1-alkenylcyclopropyl esters and 1-alkynylcyclopropyl chlorides catalyzed by palladium(0) (1992)
    s.l. : American Chemical Society
    Journal of the American Chemical Society 114 (1992), S. 4051-4067 
    Details
    ISSN: 1520-5126
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ja00037a006
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Methods of stunning freshwater fish: impact on meat quality and aspects of animal welfare (1997)
    Springer
    Zeitschrift für Lebensmittel-Untersuchung und -Forschung 204 (1997), S. 282-286 
    Details
    ISSN: 1431-4630
    Keywords: Key words Fish stunning ; Substantial quality ; Organoleptic properties
    Source: Springer Online Journal Archives 1860-2000
    Topics: Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  Taking into account aspects of meat quality and animal welfare, three methods of stunning fish were compared: a manual technique (blow on the head, stab in the neck), one using electricity and one using CO2. The following results were obtained using eel (n=72), carp (n=120) and trout (n=54). From the viewpoint of animal welfare, the effects on the fish were judged. Excitation and mucus secretion as well as the time taken for the fish to be anaesthetized were recorded. With manual and electrical stunning, all fish were anaesthetized almost immediately, while using CO2 it took 3.2 min (trout), 9.2 min (carp) and 109.7 min (eel) on average. After slaughter and after 3 and 8 days of storage on ice, the fish meat quality parameters, i.e. pH value, water-holding capacity and rigor mortis, were measured. CO2 stunning gave rise to the lowest pH values and water-holding capacities. Rigor mortis in carp and eel advanced the most. Testing of raw and prepared fish was performed by a panel assessing organoleptic properties. In many cases, fish anaesthetized manually were ranked to be better than those in the other groups.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002170050078
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Molecular methods for the analysis of Clostridium perfringens relevant to food hygiene (1999)
    Oxford, UK : Blackwell Publishing Ltd
    FEMS immunology and medical microbiology 24 (1999), S. 0 
    Details
    ISSN: 1574-695X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Notes: Clostridium perfringens continues to be a common cause of food-borne disease [1,2]. It produces an enterotoxin (CPE) which is released upon lysis of the vegetative cell during sporulation in the intestinal tract. Catering premises with insufficient cooling and reheating devices often seem to be the cause of outbreaks of C. perfringens food poisoning. Typing of C. perfringens is of great importance for investigating sources of food poisoning cases and for studying the epidemiology of this microorganism. This report describes the examination of 155 C. perfringens isolates by molecular methods. Isolates were taken from 10 food poisoning outbreaks and cases (n=34, food and fecal isolates) and from meat and fish pastes (n=121). Isolates were characterized by plasmid profiling, ribotyping, and/or macrorestriction analysis by pulsed-field gel electrophoresis (PFGE). Results show that all three methods are suitable for classifying C. perfringens isolates below the species level. Ribopatterns and PFGE patterns can be interpreted more easily than plasmid profiling results and can be recommended for contamination studies and epidemiologic investigation of food poisonings associated with C. perfringens.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1574-695X.1999.tb01295.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Short protocol for pulsed field gel electrophoresis of a variety of Clostridia species (1999)
    Oxford, UK : Blackwell Publishing Ltd
    FEMS immunology and medical microbiology 24 (1999), S. 0 
    Details
    ISSN: 1574-695X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Notes: While pulsed field gel electrophoresis has become an important tool for genotyping of bacteria, one of its drawbacks is that standard methods are rather time-consuming. In order to overcome this problem, shortened procedures for DNA preparation have been developed for some bacterial species. The aim of this study was to examine if a short procedure used for pulsed field gel electrophoresis of Clostridium botulinum could be applied to other Clostridia species. For this, the protocol was modified and used to prepare the DNA of 34 strains of 25 different Clostridia species. In contrast to a standard procedure, which takes at least 5 days from DNA extraction to completion of the electrophoresis, this protocol yielded results within 2 days. In order to directly compare the results of the short protocol with those of the standard, long procedure, parallel DNA preparations were performed using both methods and the two DNA samples thus obtained per strain were then run on the same gel. Briefly, the procedure was as follows. After embedding the bacterial cells in agarose, the agarose blocks were incubated for 1 h in lysis solution containing lysozyme, mutanolysin, lysostaphin and RNase. This was followed by a 1-h proteinase K treatment. Then, slices were cut from the agarose blocks and washed for 15 min in TE buffer, these washes were repeated four times with fresh TE. After a 2-h restriction with SmaI, electrophoresis was carried out overnight.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1574-695X.1999.tb01296.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Zur Vereinfachung der Bestimmungsmethoden für Wasser, Fett und Asche in Fleisch und Fleischerzeugnissen (1991)
    Springer
    European food research and technology 193 (1991), S. 445-448 
    Details
    ISSN: 1438-2385
    Source: Springer Online Journal Archives 1860-2000
    Topics: Process Engineering, Biotechnology, Nutrition Technology
    Description / Table of Contents: Zusammenfassung Es wurden Untersuchungen mit dem Ziel durchgeführt, die Bestimmungen von Wasser, Fett und Asche mit einer Probeneinwaage von nur noch ca. 5 g in einem Arbeitsgang zusammenzufassen. Bei dieser modifizierten Methode wird die homogenisierte Probe auf ein Faltenfilter gestrichen und zur Bestimmung des Wassergehaltes getrocknet. Dann wird das Filter mit der getrockneten Probe in einem Soxhletaufsatz mit Petroleumbenzin extrahiert und schließlich mit der entfetteten Probe in einem Porzellantiegel verascht. Bei eigenen Untersuchungen zeigte sich, daß sich die Ergebnisse zwischen konventioneller Methode nach § 35 LMBG und modifizierter Bestimmungsmethode nur sehr wenig unterscheiden (Wertedifferenzen durchschnittlich 0,07–0,34% absolut). Bei einem Ringversuch zeigten die Ergebnisse der sechs beteiligten Untersuchungslabors im Durchschnitt ähnlich geringe Unterschiede (0,07–0,50% absolut).
    Notes: Summary The aim of the tests was to combine the determination of water, fat and ash in a single operation using samples of about 5 g only. With this modified method, the homogenized sample was spread evenly on to a folded filter and dried in order to determine the water content. The filter with the dried sample was extracted with petroleum benzene in a Soxhlet apparatus. Finally, the fat-free sample was ashed in a crucible. Our own tests showed that the results achieved by the conventional method according to § 35 of the LMBG and those achieved by the modified method differed only very slighty (average difference in values 0.07–0.34% absolute). The differences between the results of six laboratories, participants in a small cooperative test, were on average also very small (0.07–0.50% absolute).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01187336
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Versatile Synthesis of Enantiomerically Pure 2-Alkoxy-1-Ethynylcyclopropanes and their Application in the Synthesis of Enantiomerically Pure Bicyclo-[3.3.0]oct-1-en-3-onesCyclopropyl Building Blocks for Organic Synthesis, Part 31. Part 30: T. Heiner, S. Michalski, K. Gerke, G. Kuchta, M. Buback, A. de Meijere, Synlett 1995, 335; Part 29: J. L. Coudret, K. Ernst, A. de Meijere, B. Waegell, Synthesis 1994, 920.Dedicated to Professor Manfred Regitz on the occasion of his 60th birthday (1996)
    Weinheim : Wiley-Blackwell
    Chemistry - A European Journal 2 (1996), S. 545-555 
    Details
    ISSN: 0947-6539
    Keywords: alkynes ; asymmetric syntheses ; cyclopropanes ; spiro compounds ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A variety of chiral, nonracemic 2-alkoxy-1-alkynylcyclopropanes 7 were synthesized in good to very good yields from enantiomerically pure glycidol derivatives (glycidol tosylate, epichlorohydrin) by boron trifluoride promoted addition of lithium trimethylsilylacetylide followed by protection of the secondary hydroxyl group and finally a diastereoselective γ-elimination. The 2-ethoxy derivative (S,R)-7 b was deprotonated with n-butyllithium, and the resulting 1-lithio-2-ethoxy derivative (S,R)-20 functionalized by treatment with oxygen followed by tosyl chloride. Protodesilylation and catalytic hydrogenation smoothly furnished 1-ethenylcyclopropyl sulfonates, which underwent a clean Pd0-catalyzed SN2′-type substitution with dimethyl propargylsodiummalonate to give the (E)-configurated enyne (R,E)-26 with a methylenecyclopropane end group. A diastereoselective Pauson-Khand reaction completed the sequence to give the enantiomerically pure spirocyclopropaneannelated bicyclo[3.3.0]octane derivative 31.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/chem.19960020514
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Preparation and Properties of New Methano-Bridged Dibenzo[c,g]phenanthrenesDedicated to Professor Henry Shine on the occasion of his 70th birthday. (1993)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 126 (1993), S. 1635-1641 
    Details
    ISSN: 0009-2940
    Keywords: [5]Helicenes, methano-bridged ; Aromatic hydrocarbons, polycyclic ; Cycloheptatriene, all-benzoanellated, flexibility of ; Distorted aromatic rings ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Intramolecular Friedel-Crafts alkylation of 1-(hydroxymethyl)[5]helicenes 1-R and 15-Me leads to 10,11-methano-bridged dibenzo[c,g]phenanthrenes 2-R and 16-Me, respectively. These molecules are shaped like the back of a turtle as shown by X-ray crystal structure analysis. Their nonplanarity, however, is not rigid, as revealed by the temperature dependence of their 1H-NMR spectra. With inversion barriers of about 62.4 and 67.1 kJ mol-1 2-H and 2-Me are surprisingly flexible. A remarkable diastereoselectivity is observed in the addition of methyl- and phenylmagnesium bromide to 1-formyl[5]helicenes 14-Me leading to secondary alcohols 15a, b-Me, which cyclize to bridged hydrocarbons 16a, b-Me, in which the substituents R=Me, Ph are in the thermodynamically less favorable endo-position. Upon heating, endo-16a,b-Me isomerize to exo-6a, b-Me irreversibly.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19931260722
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...