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991.
D. G. Mazhakin V. K. Khlestkin A. Ya. Tikhonov L. B. Volodarsky 《Russian Chemical Bulletin》1996,45(4):880-884
Derivatives of 1,4-dihydroxypiperazine-2,3-dione were obtained by reaction of cis-1,2-bis(hydroxyamino)cycloalkanes with diethyl oxalate. Their alkylation with CH2N2 or Mel afforded 1,4-dimethoxypiperazine-2,3-diones. Hydrolysis of the latter gave 1,2-bis(methoxyamino)cycloalkanes.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 925–929, April, 1996. 相似文献
992.
U. M. Dzhemilev A. G. Ibragimov A. B. Morozov R. R. Muslukhov G. A. Tolstikov 《Russian Chemical Bulletin》1991,40(7):1425-1427
A novel approach was developed for the stereoselective synthesis of trans-3,4-dialkyl-substituted aluminacyclopentanes from -olefins, metallic magnesium, and EtAlCl2 in the presence of catalytic amounts of Cp2ZrCl2. The hydrolysis and deuterolysis products of the 3,4-dialkyl-substituted aluminacyclopentanes obtained are only in the trans configuration.For previous communication, see [1].Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1607–1609, July, 1991. 相似文献
993.
Z. P. Arkhangel'skaya A. V. Krasnobryzhii M. M. Loginova T. B. Kas'yan E. V. Apollonova 《Russian Journal of Applied Chemistry》2005,78(9):1433-1437
The degree of charging of a nickel oxide electrode composed of spherical nickel hydroxide in a nickel-zinc battery was studied in anodic oxidation of the electrode in KOH solutions of different concentrations, containing hydroxozincate ions. 相似文献
994.
V. N. Yuskovets A. V. Moskvin L. E. Mikhailov B. A. Ivin 《Russian Journal of General Chemistry》2005,75(1):134-146
Readily available 5-acyl-4-hydroxy-3,6-dihydro-2H-1,3-thiazine-2,6-diones with primary alkyl- and arylamines in mild conditions (boiling in propan-2-ol) to give Schiff bases. In more rigid conditions (boiling in DMF), the reaction is accompanied by COS liberation and provides 1-substituted 6-alkyluracils. This previously unknown reaction possesses a considerable synthetic potential and can be considered as a new, general, and regioselective synthetic approach to 1-substituted 6-alkyluracils.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 1, 2005, pp. 146–158.Original Russian Text Copyright © 2005 by Yuskovets, Moskvin, Mikhailov, Ivin.For communication CXXI, see [1]. 相似文献
995.
B. Kubica M. Tuteja-Krysa Z. Szeglowski 《Journal of Radioanalytical and Nuclear Chemistry》1996,213(6):411-418
Sorption studies of Ra, Ba, Fr and Cs on nickel hexacyanoferrate(II) composite ion exchanger from hydrochloric acid and EDTA solutions are presented. 相似文献
996.
997.
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999.
Paulus H Müller KH Melzer W Peine HW Thier B Weisgerber A 《Analytical and bioanalytical chemistry》1995,353(3-4):369-371
The recently developed High Frequency Mode HFM of electron gas SNMS allows investigations on insulating samples with the well known advantages of the SNMS Direct Bombardment Mode DBM for the analysis of conducting samples. HFM has been applied to analyses of different historic ceramic and glass samples in order to demonstrate the possibilities of SNMS in this field. It is shown that manufacturing places of ceramic samples could be distinguished by SNMS mass spectra ("fingerprints"). Furthermore questions of the constituents of colour remains on a painted ceramic ("Kaisermedaillon") could be answered by our SNMS analyses. SNMS investigations have been also applied to corrosion phenomena on different glass samples. 相似文献
1000.