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991.
The alkaloids imperialine, imperialone, peumisine, petiline, petilidine, and the new bases petisine (I) and petisinine (III) have been isolated from bulbs ofPetilium raddeana (Regl.) Vved. On the basis of spectral characteristics and passages to a known compound, the structure of 3β-hydroxy-Δ22(N)-22,26-iminocholestane-6,23-dione has been established for (I) and petisine 3β-glucopyranoside for (III). 相似文献
992.
M. Fischer W. Knoche P. D. I. Fletcher B. H. Robinson N. C. White 《Colloid and polymer science》1980,258(6):733-742
Summary Complex formation between divalent metal ions and the hydrophilic murexide anion in the presence of anionic micelles has been employed to study aspects of micelle formation, the binding of divalent metal ions to micelles, and the kinetics of metal-complex formation in the presence of micelles.
With 8 figures and 1 table
Dedicated to Prof.G. Rehage on the occasion of his 60th birthday. 相似文献
Zusammenfassung Die Komplexbildung zweiwertiger Metallionen mit dem hydrophilen Indikator Murexid wurde in Gegenwart anionischer Mizellen untersucht. Die Indikatorreaktion wurde benutzt, um Aussagen über Mizellbildung, Bindung zweiwertiger Metallionen an Mizellen und die Kinetik der Metallkomplexbildung bei Anwesenheit von Mizellen zu erhalten.
With 8 figures and 1 table
Dedicated to Prof.G. Rehage on the occasion of his 60th birthday. 相似文献
993.
D. I. Dimitrov L. K. Jankov A. D. Stefanova G. D. Draganov 《Monatshefte für Chemie / Chemical Monthly》1970,101(3):668-673
Zusammenfassung Es wurde der Einfluß der Kobalt- und Mangansalze der -, - und -Pyridincarbonsäuren auf die Luftoxydation von Rutylbenzol in flüssiger Phase untersucht. Dabei wurde festgestellt, daß das Kobaltpicolinat, Manganisonicotinat und Kobaltisonicotinat den Oxydationsverlauf zur Bildung von Carbonylverbindungen und Säuren lenken. Das Manganpicolinat weist ein selektives Oxydationsvermögen auf, vorwiegend zur Bildung von Estern.
Mit 5 Abbildungen 相似文献
Liquid phase oxidation of butyl-benzene in presence of Co and Mn pyridine carboxylates
The influence of Co- and Mn-salts of -, - and -pyridinecarboxylic acids, resp., on the oxidation of butylbenzene by air has been studied. It has been found that the Co salt of picolinic acid, Mn and Co isonicotinate direct the oxidation process in favour of carbonyl compounds and acids. With the Mn salt of picolinic acid, the oxidation mainly gives esters.
Mit 5 Abbildungen 相似文献
994.
A. Zeman und I. P. G. Wirotama 《Fresenius' Journal of Analytical Chemistry》1969,247(3-4):155-158
Zusammenfassung 2,4-Dinitrophenylderivate von Aminen (DNP-Amine) werden dünnschicht-chromatographisch und massenspektrometrisch untersucht. Die Fragmentierung der Verbindungen bei Elektronenbeschuß wird diskutiert.Die Untersuchungen zeigen, daß Amine als DNP-Derivate bis auf einige kritische Paare dünnschicht-chromatographisch getrennt werden können. Aus den Massenspektren der DNP-Amine kann die Struktur eines Amins so weit ermittelt werden, daß durch Vergleich mit authentischem Material und IR-Spektroskopie eine rasche und sichere Identifizierung möglich ist.
Identification of aminesI. Thin-layer chromatography and mass spectrometry of 2,4-Dinitrophenyl derivatives (DNP-amines)
2,4-Dinitrophenyl derivatives of amines (DNP-amines) were investigated by thin-layer chromatography and mass spectrometry. The fragmentation of the compounds upon electron impact is discussed.The investigations show that amines in their form as DNP-derivatives can be separated by TLC except for some critical pairs. From the mass spectra of the DNP-amines the structure of an amine can be elucidated so far that a quick and reliable identification is possible by comparison with authentic material and IR spectroscopy.相似文献
995.
N. V. Ivasyuk É. Kh. Mukhametzyanova I. M. Shermergorn 《Russian Chemical Bulletin》1968,17(7):1532-1533
Conclusions The reaction of bis(chloromethyl)phosphonic acid with thiourea gave the hydrochloride of bis(thio-ureylmethyl)phosphonic acid, the alkaline decomposition of which gave bis(mercaptomethyl)phosphonic acid.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1625–1626, July, 1968. 相似文献
996.
Synthesis of lepidine and its derivatives from aromatic amines and quaternary salts of Mannich bases
B. I. Ardashev E. Sh. Kagan V. V. Mezheritskii T. F. Sidorova 《Chemistry of Heterocyclic Compounds》1967,2(2):177-179
A quaternary salt of 4-(diethylamino)butan-2-one, methyldiethyl-3-ketobutylammonium methyl sulfate, is used as an alkylating agent to synthesize lepidine and 1-phenyllepidine salts. The method gives good yields, under mild conditions, of lepidine and 1-phenyllepidine perchlorate. An intermediate product is isolated, and a reaction mechanism suggested. 相似文献
997.
Summary 1. The phospholipids of cottonseed oil contain ten fatty acids.2. The positions of the double bonds in the aliphatic chain in the newly discovered unsaturated fatty acids — palmitlinoleic, palmitlinolenic, linolenic, and eicosadienic — have been established by the method of gas-liquid chromatography: they are present at the 6, 9; 6, 9, 12; 9, 12, 15; and 11, 14 carbon atoms, respectively, counting from the carboxyl end of the chain. A saturated fatty acid (myristic) has been found in the phospholipids of cottonseed oil for the first time.Khimiya Prirodnykh Soedinenii, Vol. 1, No. 3, pp. 199–201, 1965 相似文献
998.
Application of neutron activation analysis for mercury species determination in scalp hair samples from Malaysia, Libya and Jordan 总被引:1,自引:0,他引:1
The sorption of Ba2+ ion on natural kaolinite and chlorite-illite clays was investigated at different initial concentrations and temperatures
using the radiotracer method. The sorption data were well described by Freundlich and Dubinin-Radushkevich isotherms. Ba2+ sorption on both clays showed an exothermic behavior with ΔH° (kJ/mol) values being -7 and -5 for sorption on kaolinite and chlorite illite mixed clay, respectively. The ΔG° values indicate that the sorption was spontaneous with sorption energies corresponding to ion-exchange type sorption. X-ray
diffraction studies showed that no significant change in the matrix of the clays occurred upon Ba2+ sorption.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
999.
Summary The [h]phenylene C6h
H2h+4 isomers are enumerated up toh=12. The numbers are compared with old and new data for C
n
H5 isomers of benzenoids, fluoranthenoids and biphenylenoids.
Anzahl möglicher Isomerer von Phenylenen
Zusammenfassung Die Anzahl der [h]Phenylen-Isomeren C6h H2h+4 wurde bish=12 ausgewertet. Die Zahlen wurden mit alten und neuen Daten für C n H s -Isomere von Benzenoiden, Fluoranthenoiden und Biphenyloiden verglichen.相似文献
1000.
A. V. Palii M. I. Belinskii V. E. Fainzil'berg B. S. Tsukerblat 《Theoretical and Experimental Chemistry》1989,24(4):382-387
On the basis of a microscopic calculation of the inelastic neutron scattering spectra for scattering by exchange dimer clusters, we have determined the conditions for applicability of the semiphenomenological approach to determination of the scattering cross sections based on the spin model. The scattering cross sections obtained in the spin model are distinguished from the exact values by the fact that modified form factors of the SS transitions are used in the exact calculation instead of the magnetic form factors of the individual atoms. In the case of weak overlap of the one-electron wave functions for different centers, the exact scattering cross sections coincide with the cross sections calculated on the basis of the spin model.We have investigated the inelastic neutron spectrum for scattering by a dimer d2–d1 of mixed valency. Tunneling transfer of the extra electron leads to splitting of the exchange line corresponding to the transition with S=1 in the system with localized electrons and the appearance of new lines. The spectrum consists of a series of forbidden transitions (with conservation of parity and S=1) and allowed transitions (with a change in parity and S=0, 1). The results obtained allow us to determine the parameters of Heisenberg and double exchange in mixed-valency dimers using the inelastic neutron scattering spectra.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 24, No. 4, pp. 392–398, July–August, 1988. 相似文献