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1972 (397)
21Author    Kurt Steinle, Max SchmidtRequires cookie*
 Title    O-Benzotrithiolon-2, ein beständiges Thionyl- mercaptid 1 o-Benzotrithiolon-2, a Stable Thionylmercaptide  
 Abstract    Bis jetzt konnten nur wenige Verbindungen mit der O 
  Reference    (Z. Naturforsch. 27b, 83—84 [1972]; eingegangen am 30. Oktober 1971) 
  Published    1972 
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 TEI-XML for    default:Reihe_B/27/ZNB-1972-27b-0083_n.pdf 
 Identifier    ZNB-1972-27b-0083_n 
 Volume    27 
22Author    Felix FriedbergRequires cookie*
 Title    Covalent Binding of Amino Acids to Proteins Due to Gamma Irradiation  
 Abstract    Exposure of lyophilized native globular proteins to about 30 Mrads causes aggregation of the protein mole-cules. There is no evidence of extensive degradation of these globular molecules. Similarly, if the S-carboxy-methylated form (i. e., a form devoid of disulfide linkages) is exposed to the gamma ray, no indication of marked degradation of the polypeptide chain ap-pears, and again the molecules are prone to aggregate. On the other hand, lathyritic collagen exhibits a defi-nite lowering of its molecular weight under the same conditions 1 . GARRISON 2 suggests that in the more complex amino acid residues the long-lived spin centers might be located on side-chains. In the case of irradiated globular proteins, recombination of these radicals to form new intramolecular bonds may be favored by con-straints due to the secondary and tertiary structure. MARCIANI and TOLBERT 3 recently reported that solid lysozyme irradiated with 26 Mrads and fractionated on BioGel P-60 shows absence of polymeric forms upon SDS Polyacrylamide gel electrophoresis after re-duction and alkylation, indicating that "most of the polymers" are due to disulfide bond formation. Since such a finding is incongruous with the observation that aggregates of S-carboxymethylated globular proteins are not prevented from forming even though the — S —S— bonds are reduced and alkylated and thus are not available for intermolecular disulfide exchange, a reexamination of the relative role of carbon bond and sulfur bond formation upon irradiation was at-tempted. 118.3 mg bovine ribonuclease (HI A) and 20 mg DL-aspartic acid [4-u C] were dissolved in 12 ml dist. HoO and lyophilized. Approximately 25 mg of the re-sulting material was sealed into glass tubes, evacuated 
  Reference    (Z. Naturforsch. 27b, 85 [1972]; received November 2 1971) 
  Published    1972 
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 TEI-XML for    default:Reihe_B/27/ZNB-1972-27b-0085_n.pdf 
 Identifier    ZNB-1972-27b-0085_n 
 Volume    27 
23Author    Jörn Bücking, Manfred Herbst, Peter PiontekRequires cookie*
 Title    Über den Einfluß der Ca 20 -Konzentration auf die Latenzrelaxation des Skeletmuskels On the Dependence of Latency Relaxation of Skeletal Muscle on Ca 20 -Concentration  
  Reference    (Z. Naturforsch. 27b, 86 [1972]; eingegangen am 12. Oktober 1971 revidiert am 5. November 1971) 
  Published    1972 
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 TEI-XML for    default:Reihe_B/27/ZNB-1972-27b-0086_n.pdf 
 Identifier    ZNB-1972-27b-0086_n 
 Volume    27 
24Author    KarlL. KompaRequires cookie*
 Title    Infrarot-Photochemie mit Lasern? Infrared Photochemistry with Lasers?  
 Abstract    The possibility of controlled chemical reactions by resonance laser activation of molecular vibrational modes is considered. This produces a selective heating of one or more vibrational de-grees of freedom and a correspondingly rapid increase in the reaction rates. The competition be-tween chemical processes and relaxation by energy transfer to other degrees of freedom is discus-sed. The verification of this new reaction principle requires lasers with realistic parameters. A few experimental results are reviewed. 
  Reference    (Z. Naturforsch. 27b, 89—94 [1972]; eingegangen am 25. Oktober 1971) 
  Published    1972 
  Keywords    Infrarot-Photochemie, Reaktionskinetik, Schwingungsrelaxation, Infrarot-Laser, Literaturzusammenfassung 
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 TEI-XML for    default:Reihe_B/27/ZNB-1972-27b-0089.pdf 
 Identifier    ZNB-1972-27b-0089 
 Volume    27 
25Author    Peter Waldmeier, Bernhard Prijs, Helmut SigelRequires cookie*
 Title    On the Kinetics of the Catalase-Like Activity of the Cobalt(II) Complex of 4,4',4",4"'-Tetrasulfophthalocyanine  
 Abstract    The decomposition of H202 , catalyzed by the Co 2 ® complex of 4,4',4",4'"-tetrasulfophthalo-cyanine (ConPTS), was investigated in the pH range 3.8 through 10 by measuring the initial rate, i;0=d(O2)/d£, of the increasing formation of 02 (25°; 1 = 0.1). In this pH range v0 is proportional to the initial concentration of H202 (determined at pH 5.0 and 9.2). Due to the dimerization (log KD=5.47±0.09 at natural ionic strength and about 7.63 ±0.16 in 0.1m NaC104; 25°) and polymerization of ConPTS the catalyst and its reaction order are difficult to establish: Based on the experimental evidence it is suggested that v0 is proportional to the concentration of monomer CoHPTS. Additionally, there is evidence that the experimentally determined v0 contains the con-tributions of a pH-independent and a pH-dependent reaction course. These results are analog to those obtained earlier with FelHPTS as catalyst. A mechanism for the catalyzed disproportionation of H202 by Co n PTS is proposed. The catalase-like activity of Co In PTS(OH) is smaller than that of Co n PTS and the pH-dependence is different. The decomposition of hydrogen peroxide accor-ding to equation (1) 2 H202 02 + 2 H20 (1) 
  Reference    (Z. Naturforsch. 27b, 95—100 [1972]; received October 26 1971 revised November 11 1971) 
  Published    1972 
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 TEI-XML for    default:Reihe_B/27/ZNB-1972-27b-0095.pdf 
 Identifier    ZNB-1972-27b-0095 
 Volume    27 
26Author    Pentaborate, K. Frey, E. FunckRequires cookie*
 Title     
 Abstract    The aim of the investigations was the characterization of the polyborates, as far as IR-spectro-scopy is concerned. The investigations covered the absorption spectra of different pentaborates, in-cluding those substituted by 10 B-, n B-, and H-D-isotopes, as well as the reflection spectra of potas-sium-pentaborate single crystals with polarized radiation. The concept of group frequency ana-lysis was successfully applied to the interpretation of the pentaborate-spectra; almost all bands were attributed to vibrations of the B03 , B04 and OH units. 1. Zielsetzung und Charakterisierung der unter-suchten Verbindungsklasse Ziel der Untersuchung und Methode 
  Reference    (Z. Naturforsch. 27b, 101—125 [1972]; eingegangen am 6. November 1971) 
  Published    1972 
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 TEI-XML for    default:Reihe_B/27/ZNB-1972-27b-0101.pdf 
 Identifier    ZNB-1972-27b-0101 
 Volume    27 
27Author    KlausGustav Heumann, KarlHeinrich LieserRequires cookie*
 Title    Untersuchung von Calciumisotopieeffekten bei heterogenen Austauschgleichgewichten Investigation of I&otopic Effects of Calcium in Heterogeneous Exchange Equilibria  
 Abstract    The following heterogeneous exchange equilibria have been examined for isotopic effects: CaCOs/Caf®., , Ca-GBHA/Ca?®.> and Ca?®owex ",/Caüg., (GBHA = glyoxal-bis(2-hydroxyanil)). The isotopic ratios 44 Ca/ 40 Ca and 48 Ca/ 40 Ca were determined by means of a mass spectrometer with a thermal ion source. In the system CaC03/Caf®., the elementary separation factor was found to be less than \%o or 0,5%o per mass unit, respectively. For the exchange in the system Ca-GBHA/Caf®.> in the concentration range from 0.011 to 0.84 M an elementary separation factor less than \%o per mass unit was found; from a three-stage experiment at a calcium concentration of 1.23 M it was concluded that the elementary isotopic effect is less than 0.4%» per mass unit. Therefore no isotopic fractionation is to be expected for precipitation of inorganic or organic calcium salts. An enrichment of the heavier calcium isotopes in the solution was found in the case of the exchange in a Dowex 50-X12 loaded column. The isotopic effect depends on the concentration of the hydrochloric acid used as the eluent. Calcium besitzt 6 stabile Isotope: 40 Ca, 42 Ca, 
  Reference    (Z. Naturforsch. 27b, 126—133 [1972]; eingegangen am 27. Oktober 1971 revidiert am 7. November 1971) 
  Published    1972 
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 TEI-XML for    default:Reihe_B/27/ZNB-1972-27b-0126.pdf 
 Identifier    ZNB-1972-27b-0126 
 Volume    27 
28Author    S. M. Murgia, G. Paliani, G. CardaciRequires cookie*
 Title    Electrochemical Behaviour of the Fe(CO) 3 NO° Ion  
 Abstract    The Polarographie behaviour of [ (C2H5)4N] ® [Fe(CO)3NO] e has been investigated at the mercury dropping electrode and platinum stationary electrode. It was found that the complex displays two anodic and one cathodic waves. On the basis of the results obtained a mechanism is proposed and discussed. 
  Reference    (Z. Naturforsch. 27b, 134—136 [1972]; received November 12 1971) 
  Published    1972 
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 TEI-XML for    default:Reihe_B/27/ZNB-1972-27b-0134.pdf 
 Identifier    ZNB-1972-27b-0134 
 Volume    27 
29Author    Heinrich Marsmann, Hans-Georg HornRequires cookie*
 Title    H-, 13 C-und 31 P-KMR-Spektren einiger ditertiärer Phosphine 1 H-, 13 C-and 31 P-NMR Spectra of Some Ditertiary Phosphines  
 Abstract    13 C-and 31 P-NMR data of some ditertiary phosphines are given and 1 H-NMR spectra of these compounds in different solvents are discussed. 
  Reference    (Z. Naturforsch. 27b, 137—139 [1972]; eingegangen am 23. Oktober 1971) 
  Published    1972 
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 TEI-XML for    default:Reihe_B/27/ZNB-1972-27b-0137.pdf 
 Identifier    ZNB-1972-27b-0137 
 Volume    27 
30Author    E. Koerner, Von Gustorf, J. C. Hogan, R. WagnerRequires cookie*
 Title    Di-^-halogen-bis (tricarbonyliron) : Formation of Dimeric Halogen Iron Tricarbonyls in the Thermal and Photochemical Reaction of Iron Carbonyls with Hydrogen Halides  
 Abstract    The hitherto unknown dimeric halogen iron tricarbonyls [Fe(CO)3X]2 (X = Br, I) have been prepared by reacting HBr or HI with Fe2(CO)9 and by the photoreaction of Fe(CO)5 with HBr. The properties of these compounds are discussed. Halogencarhonyle des Eisens vom Typ Fe(CO)4X2, 
  Reference    (Z. Naturforsch. 27b, 140—142 [1972]; eingegangen am 12. November 1971) 
  Published    1972 
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 TEI-XML for    default:Reihe_B/27/ZNB-1972-27b-0140.pdf 
 Identifier    ZNB-1972-27b-0140 
 Volume    27 
31Author    Heinz SterkRequires cookie*
 Title    Über die Dimerisierung von 2-Äthyl-keten-carbonsäureäthylester Dimerisation of 2-Ethyl-keten-carbonicacidethylester  
 Abstract    It ought to be shown by the EHT-method and nmr-spectroscopic investigations that the dimeri-sation of 2-ethyl-keten-carbonic-acidethylester behaves like a cycloaddition. 
  Reference    (Z. Naturforsch. 27b, 143—146 [1972]; eingegangen am 22. April 1971 revidiert am 21. August 1971) 
  Published    1972 
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 TEI-XML for    default:Reihe_B/27/ZNB-1972-27b-0143.pdf 
 Identifier    ZNB-1972-27b-0143 
 Volume    27 
32Author    I. Schuphan, B. Sajko, K. BallschmiterRequires cookie*
 Title    Zum chemischen und photochemischen Abbau der Cyclodien-Insektizide Aldrin, Dieldrin, Endosulfan und weiterer Hexachlorbicyclo-[2.2.1]-hepten-Derivate * The Chemical and Photochemical Degradation of the Cyclodien-Insecticides Aldrin, Dieldrin, Endosulfan and other Hexachloronorbornene Derivatives  
 Abstract    The conversion of the hexachloronorbornene-moiety of persistent cyclodiene pesticides has been studied by hydrolysis-and photolysis (UV) reactions. The chemical changes have been monitored by means of a microtitration method for chloride ions and electron capture gas chromatography. The 2,3-disubstituted hexachloronorborn-5-enes give a comparably easy loss of 1 mole chloride ions per mole compound if one of the substituents is a hydroxymethylene group, whereas with two carboxylic acid groups in the 2,3-position — that is chlorendic acid — or a further cycle or bi-cycle — that is endosulfanether or dieldrin — the compounds proved to be very stable. The alka-line stability of aldrin and dieldrin corresponds to their persistence in the ecosystem. 
  Reference    (Z. Naturforsch. 27b, 147—156 [1972]; eingegangen am 22. November 1971) 
  Published    1972 
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 TEI-XML for    default:Reihe_B/27/ZNB-1972-27b-0147.pdf 
 Identifier    ZNB-1972-27b-0147 
 Volume    27 
33Author    Walter Vötsch, F.Alfred AndererRequires cookie*
 Title    The N-terminal Amino Acid Sequence of Sheep Heart Myoglobin  
 Abstract    The iV-terminal amino acid sequence of residues 1 — 50 of sheep heart myoglobin was deter-mined using the automatic E d m a n degradation procedure. The amino acid phenyl-thiohydan-toins were identified by thin layer chromatography and/or by mass spectrometry. 
  Reference    (Z. Naturforsch. 27b, 157—159 [1972]; received October 29 1971) 
  Published    1972 
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 TEI-XML for    default:Reihe_B/27/ZNB-1972-27b-0157.pdf 
 Identifier    ZNB-1972-27b-0157 
 Volume    27 
34Author    W. Draber, K. H. Büchel, G. SchäferRequires cookie*
 Title    Quantitative Structure-Activity Studies of Hydrazones, Uncouplers of Oxidative Phosphorylation  
 Abstract    a-Acyl-a-cyanocarbonyl-phenylhydrazones are effective uncouplers of oxidative phosphorylation. The p/50-values of a series of 60 hydrazones with substituent variations in six positions of the molecule were determined in rat liver mitochondria. They ranged from 4.96 to 7.06. The bio-logical data together with physico-chemical compound and substituent parameters were analysed by multiple regression techniques to establish the structure activity relationship. The integral parameters pKa and log P (partition coefficient) gave correlations of only moderate significance. Good agreement of found and calculated p/50-values was obtained by an equation with electronic (o) and hydrophobic (it) substituent parameters in linear and quadratic terms. It is con-cluded that the contribution of a substituent to uncoupling activity depends on its position in the molecule. The activity is enhanced by hydrophobic shielding of the acidic NH-group. The relevancy of these results in relation to current theories on the mechanism of oxidative phosphorylation is discussed. 
  Reference    (Z. Naturforsch. 27b, 159—171 [1972]; received November 3 1971) 
  Published    1972 
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 TEI-XML for    default:Reihe_B/27/ZNB-1972-27b-0159.pdf 
 Identifier    ZNB-1972-27b-0159 
 Volume    27 
35Author    Gerhard VierkeRequires cookie*
 Title    On the Impossibility of an OH-Radical Model for Photosynthetic Water Oxidation Uber die Unmöglichkeit eines OH-Radikalmodells für die photosynthetische Wasseroxidation  
 Abstract    OH-Radical Model for Photosynthetic Water Oxidation If it is assumed that the oscillating 02 flash yield sequence of algae and chloroplasts pre-dominantly reflects an inherent property of the 02 evolving system of the photosynthetic apparatus it is shown that the OH-radical model (02 production by recombination of four OH radicals) is contradictory to the experimental results because it predicts an aperiodic 02 flash yield sequence. Several experimental facts already known strongly indicate that the OH-radical model is not consistent with the kinetic model for 02 evolution of KOK et al. either. 
  Reference    (Z. Naturforsch. 27b, 172—176 [1972]; received November 27 1971) 
  Published    1972 
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 TEI-XML for    default:Reihe_B/27/ZNB-1972-27b-0172.pdf 
 Identifier    ZNB-1972-27b-0172 
 Volume    27 
36Author    Walter Oettmeier, Adelheid HeupelRequires cookie*
 Title    Identification of Flavonoids and Cinnamic Acid Derivatives from Spinach Chloroplast Preparations  
 Abstract    By immunochemical methods we had presented evidence for a primary acceptor complex for photosystem I of photosynthetic electron transport. During purification of this complex, obtained as a water soluble fraction from ether treated lyophilized chloroplasts, two low molecular fractions are also obtained, which may or may not have relation to the primary acceptor. The purification and identification of these low molecular fractions is reported. One, absorbing at 275 and 335 nm, consists of several flavonoid glycosides. The aglycon of the main component is tentatively identified as a 3-methyl-6,7-methylenedioxy-quercetagetin. The chromophore of the other low molecular fraction, absorbing at 312 nm, contains two cinnamic acid derivatives, which on alkaline hydrolysis yield p-coumaric acid. The relation of the two low molecular fractions to other fractions of various activity isolated from chloroplasts is discussed. 
  Reference    (Z. Naturforsch. 27b, 177—183 [1972]; eingegangen am 24. November 1971) 
  Published    1972 
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 Identifier    ZNB-1972-27b-0177 
 Volume    27 
37Author    Ahlert SchmidtRequires cookie*
 Title    Über Teilreaktionen der Photosynthetischen Sulfatreduktion in zellfreien Systemen aus Spinatchloroplasten und Chlorella * Enzyme Reactions Involved in Photosynthetic Sulfate-Reduction in Cell-free Systems of Spinach Chloroplasts and Chlorella  
 Abstract    Sulfatreduktion, APS, PAPS, S-Sulfoglutathion Cellfree extracts from Chlorella, spinach leaves or spinach chloroplasts convert radioactive sulfate into a S-sulfocompound already in the dark. The reaction requires ATP, Mg 2 ® ions and compounds with SH groups. The later are needed for activation of the enzym and as substrates and acceptors for the sulfogroup. The compound formed if glutathion is used has been identified as S-sulfoglutathion. Other products formed from sulfate and ATP in the dark by spinach or chlorella extracts are APS and PAPS. The formation of PAPS requires the presence of a SH-group. Both cellfree extracts transfer the sulfate group from APS and PAPS onto glutathion to form S-sulfo-glutathion. No ATP is needed in this reaction, neither with PAPS nor with APS as substrate. 
  Reference    (Z. Naturforsch. 27b, 183—192 [1972]; eingegangen am 18. November 1971) 
  Published    1972 
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 TEI-XML for    default:Reihe_B/27/ZNB-1972-27b-0183.pdf 
 Identifier    ZNB-1972-27b-0183 
 Volume    27 
38Author    H. W. KütheRequires cookie*
 Title    während der Frühentwicklung von Dermestes frischi (Coleoptera) Autoradiographic Investigations on Protein Synthesis During Early Development of Dermestes frischi (Coleoptera)  
 Abstract    Injection of tritiated phenylalanine or leucine in eggs shortly after deposition shows the im-portance and use of free amino acids during cleavage stages. First the activity is found homo-geneously distributed in the yolk system and ooplasm. In late cleavage stages the amino acids are incorporated into the periplasm of the egg. These results lead to the conclusions, that there is a continuous transfer of material out of the yolk system into cortical regions during cleavage. Secondly the first new synthetized protein fractions are located in the cortical ooplasm. 
  Reference    (Z. Naturforsch. 27b, 193—195 [1972]; eingegangen am 5. November 1971) 
  Published    1972 
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 TEI-XML for    default:Reihe_B/27/ZNB-1972-27b-0193.pdf 
 Identifier    ZNB-1972-27b-0193 
 Volume    27 
39Author    S. Marciani, M. Terbojevic, F. Dall, '. AcquaRequires cookie*
 Title    Light Scattering and Flow Dichroism Studies on DNA After the Photoreaction with Psoralen  
 Abstract    Light scattering measurements performed on DNA after irradiation in the presence of psoralen clearly show that inter strand cross linkings are present in the macromolecule. In fact after heat denaturation and successive cooling irradiated macromolecule shows a molecular weight practi-cally unchanged while a DNA sample after the same treatment shows a molecular weight half of the intact native DNA. Also the general conformation of irradiated DNA undergoes practically to no modifications after the same heat treatment while native DNA shows itself to have been strongly modified. Moreover, on the basis of flow dichroism determinations, DNA cross-linked by psoralen after heat denaturation showed to be able to restore its ordered double helix structure, during the successive cooling. It is well known that furocoumarins photoreact both in vitro 1-5 and in vivo 6,7 with nucleic acids by irradiation at 365 nm, and that this photoreac-tion can explain the biological photosensitizing pro-perties of furocoumarins. A C^cyclo-addition of the substances to the 5,6-double bond of the pyrimidine basis of DNA takes place; furocoumarins (e.g. psoralen) can react either with their 3,4-or with their 4',5'-double bond, forming therefore two types of photoadducts 8_10 . Fig. 1. Molecular structure of psoralen. 
  Reference    (Z. Naturforsch. 27b, 196—200 [1972]; received October 26 1971) 
  Published    1972 
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 TEI-XML for    default:Reihe_B/27/ZNB-1972-27b-0196.pdf 
 Identifier    ZNB-1972-27b-0196 
 Volume    27 
40Author    F. Carlassare, C. Antonello, F. Baccichetti, P. MalferRequires cookie*
 Title    On the Binding of Benz[a]pyrene to DNA "in vivo"  
 Abstract    The Possibility that "in vivo" a binding takes place between DNA and benz[a]pyrene was examined. After oral administration of 3 H-benz[a]pyrene, radioactive DNA was isolated from the skin, spleen and liver of NCLmice, and especially from the liver. This suggest that covalent binding between DNA and benz[a]pyrene takes place. Many studies described in the literature suggest a relationship between the chemical structure of seve-ral hydrocarbons and their carcinogenic power. It has been known since 1930 1 that it is possible to in-duce tumors by local treatment with 1:2,5:6-dibenz-anthracene. The possibility that light may influence carcinogenesis due to benz[a] pyrene has also been studied 2 . Many authors have reported that the carcinogenic activity depends upon a binding between the hydro-carbon, or one of its metabolites, and the cellular constituents. Some time ago it was suggested that binding to proteins was the beginning of the car-cinogenesis; it has, moreover, also been suggested that an important part of the tumoral process may be attributed to a binding between hydrocarbons and nucleic acids. There are different opinions on the possibility that such a binding occurs, both "in vitro" and "in vivo". With regard to experiments "in vivo", HEI-DELBERGER 3 up till 1964 excludes that the responsi-bility for the beginning of the carcinogenic 
  Reference    (Z. Naturforsch. 27b, 200—202 [1972]; received July 19 1971 revised November 25 1971) 
  Published    1972 
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 Identifier    ZNB-1972-27b-0200 
 Volume    27 
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