Das Ultrarotspektrum von isotaktischem Polypropylen zwischen 1500 cm−1 und 330 cm−1

Zusammenfassung Die Frequenzen der Skelettschwingungen von isotaktischem Polypropylen werden mit Hilfe des Valenzkraft-Modells berechnet und mit den im UR-Spektrum gemessenen Frequenzen verglichen. Die übereinstimmung ist so gut, da? eine Zuordnung der Banden zu den Molekelschwingungen gegeben werden kann. Dagegen k?nnen die Intensit?tsverh?ltnisse nicht gekl?rt werden. Herrn Professor Dr.Hellwege danke ich für Anregungen und Diskussionen zu dieser Arbeit. Ferner danke ich den Firmen Kalle, Wiesbaden, und Farbwerke Hoechst für die zur Verfügung gestellten Polypropylenproben, der Deutschen Forschungsgemeinschaft für die Bereitstellung des Rechenautomaten und HerrnG. Günther für die Hilfe beim Programmieren.     

Reaction of esters of thio acids of trivalent arsenic with organomagnesium compounds

Conclusions Depending on the molar ratios, the esters of the thio acids of trivalent aresnic are alkylated by organomagnesium compounds to give the corresponding tertiary arsines or the esters of the thio acids of trivalent arsenic.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 963–965, April, 1972.     

Effect of 2,2,6,6-tetramethyl-1-piperidinyloxy nitroxide substituent on kinetic parameters of pseudoliving polymerization

The main kinetic and thermodynamic parameters of the pseudoliving radical polymerization of styrene mediated by 4-linoleamido-2,2,6,6-tetramethyl-1-piperidinyloxy have been studied. It has been shown that the introduction of the said substituent into nitroxide leads to a marked reduction in the rate constant of reinitiation that is compensated for by the simultaneous reduction in the rate constant of reversible termination. As a result, the rate of pseudoliving polymerization, the rate of molecular mass growth, and the polydispersity of the polymer appear to be practically the same for processes mediated by both unsubstituted and substituted nitroxides.     

Methane conversion with carbon dioxide on nickel aluminides

The catalytic activity of several samples based on nickel aluminides in methane conversion with carbon dioxide was studied. Nickel aluminides were prepared by the method of self-propagating high-temperature synthesis. The Ni₃Al system containing the nickel metal phase exhibited high activity at temperatures above 1073 K. The systems based on Ni₂Al₃ and NiAl only containing intermetallic compound phases were inactive.     

Cyanoacetylene and Its Derivatives: XXXIV. Nucleophilic Addition of Tetrazole to Cyanoacetylenes

Nucleophilic addition of tetrazole to 4-hydroxy-4-alkyl-2-alkynonitriles and to 3-phenyl-2-propynonitrile occurred regiospecifically and afforded E-, Z-4-hydroxy-4-methyl-3-tetrazolyl-2-alkenonitriles and 3-tetrazolyl-3-phenyl-2-propenonitrile [20–40°C, 13–50 h, 4–15 wt% MOH (M = Na, K), THF (or DMSO)] in up to 69% yield. The attempt to perform cyclization of the hydroxy-containing adducts into iminodihydrofurans (KOH, ethanol, 23-25°C) resulted in vinyl nucleophilic substitution of the tetrazole moiety by an ethoxy group.     

Decarboxylierung cyclischer und acyclischer dicarboxylato-komplexe des platins

The interaction of (Ph₃P)₂PtO₂ (I) with the dicarboxylic acids HO₂C(CH₂)_nCO₂H (n = 1–3), phthalic acid and maleic acid gives the dicarboxylato complexes (Ph₃P)₂$\text{PtO(O)C(CH}{}_2\text{)}{}_{\mathrm{<mtext>n</mtext>}}\text{C(O)O}$ (II) (n = 1–3), (Ph₃P)₂$\text{PtO(O)CC}{}_6\text{H}{}_4\text{C(O)O}$ (III) and cis-[(Ph₃P)₂Pt(O(O)CCHCHC(O)OH)₂] (IV) in nearly quantitative yield. Thermal and photoinduced decarboxylation of III and IV yields the platina heterocycles (Ph₃P)₂$\text{PtC}{}_6\text{H}{}_4\text{C(O)O}$ (V) and (Ph₃P)₂$\text{PtCHCHC(O)O}$ (VI) with a carbon-platinum σ-bond. Complex VI has been characterized by an X-ray crystal structure determination.     

Improved short-lived nuclide activation analysis

A novel technique has been developed to increase the sensitivity, precision and accuracy of short-lived nuclide activation analysis and especially of delayed fission neutron counting, by improving the counting statistics. This has been achieved by approaching the irradiated sample to the detector during the counting period in order to compensate for the rapid radioactive decay by variation of the counting efficiency, permitting prolongation of the counting period with constant count rate. The sample holder movement with approximately exponentially decreasing velocity is implemented by a variable DC motor with a rotary to linear movement converter, which is being replaced by a more reliable stepping motor.     

Berberis alkaloids. XXI. Intebrine — A new N-benzylisoquinoline alkaloid from Berberis integerrima

A new N-benzylisoquinoline alkaloid — intebrine, with the composition C₂₀H₁₉NO₇ — has been isolated fromBerberis integerrima Bunge. The spatial structure of intebrine has been reliably determined by the x-ray structural method (diffractometer, CuK radiation, 972 reflections, direct method, R=0.048). Its chemical behavior, spectral characteristics, and mass-spectrometric fragmentation under electrom impact have been studied.Andizhan State Medical Institute. Institute of the Chemistry of Plant Substances, Uzbekistan Republic Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedeninii, No. 1, pp. 65–70, January–February, 1993.     

Development of a one step strip test for the detection of sulfadimidine residues.

The one step strip test described is a competitive immunoassay in which the detector reagent consists of colloidal gold particles coated with affinity purified polyclonal anti-sulfadimidine (SDD) antibodies. The capture reagent in the assay is an SDD-ovalbumin conjugate which is immobilised on the lateral flow membrane of the test device. In the test procedure, 150 microliters (four drops) of a liquid sample (buffer, urine or milk) are brought into the sample well of the test device and allowed to migrate over the membrane. The more analyte present in the sample, the more effectively it will compete with the SDD immobilised on the membrane for binding to the limited amount of antibodies of the detector reagent. A sufficient amount of SDD in the sample will therefore prevent the binding of the detector reagent to the SDD immobilised on the membrane. Therefore, a positive sample will not show a test line in the read-out zone. With spiked buffer or calf urine this was obtained at a level of > 10 ng ml-1 of SDD and with spiked (diluted) fresh cow milk at a level > 20 ng ml-1 of SDD. At these levels, the test is applicable only as a qualitative assay. The presence or absence of a test line indicates lower or higher levels of SDD, respectively. The major advantages of the one step strip test are that results can be obtained within 10 min and that all reagents are included in the test device.     

Quantitative Bestimmung von Sulfat und Sulfid (nach Oxydation) mit Hilfe des Orion-„Ionalizers“

A potentiometric procedure for the determination of sulphate has been tested. The analysis requires approx. 10–15 min time. The determination of the end-point is free from individual influences. In the determination of 0.1 N sodium sulphate an average error of the single measurement of fm=± 0.7% was observed. The more detailed complexometric method according to ?Deutsche Einheitsverfahren“ yielded an average mistake of fm=±2%. The method was applied to the determination of sulphate from sulphide (after oxidation of the latter). No considerable deviation from the gravimetrically ascertained values was noted. Borate does not interfere.