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11.
12.
K. K. Turgunov A. G. Tojiboev B. Tashkhodjaev KH. M. shakhidoyatov 《Journal of inclusion phenomena and macrocyclic chemistry》2005,53(1-2):23-26
The crystal structures of hydrate (1) and anhydrate (2) forms of 2,3-pentamethylene-3,4-dihydroquinazolin-4-one hydrochloride have been determined by X-ray structure analysis. Crystal data of 1 are 2(C13H14N2O)*3(HCl)*4.5 (H2O), triclinic P?1, Z=2, a=8.004(5), b=13.129(7), c=15.725(7) Å, α=106.45(4), β=92.61(4), γ=97.98(5), R=0.0652 and 2 are C13H14N2O*HCl, monoclinic C2/c, Z=8, a=21.360(4), b=5.954(1), c=21.263(4), β=117.89(3), R=0.0556. The crystal of the hydrate form 1is unstable. This form collapses easily with evaporation of H2O and part of HCl molecules from crystals. By recrystallizing destroyed form has been obtained stable crystal form 2. 相似文献
13.
D. Ya. Sniker R. A. Zhuk E. I. Stankevich G. Ya. Dubur S. A. Hiller 《Chemistry of Heterocyclic Compounds》1969,5(1):130-131
The reaction of alkoxy bromides with N1-(-tetrahydrofuryl) derivatives of pyrimidine bases has given a series of 6-alkoxy-5-bromo-1-(-tetrahydrofuryl)-5, 6-dihydrouracils. The hydrogenation of the 1-(-tetrahydrofuryl) derivatives of uracil and of 5-fluorouracil has been studied. It has been shown that in both cases 1-(-tetrahydrofuryl)-5, 6-dihydrouracil is formed. 相似文献
14.
A number of N1-(-butyrolactono) derivatives of 5-substituted uracils have been synthesized by condensing the sodium derivatives of the corresponding bases with -bromobutyrolactone or by the halogenation of N1-(-butyrolactono)uracil.For part I, see [1]. 相似文献
15.
We prove, that in the world of constructible sets, there does not exist a spaceX withH″ (X,Z) isomorphic to the rational numbers. The proof requires a result about the growth of Ext z Emphasis>/i (-, Z) inside of Gödel’s constructible universeL. 相似文献
16.
Walter M. F. Fabian Gert Kollenz Yunus Akcamur Tevfik Riza Kök Makbule Teczan Mehmet Akkurt Wolfgang Hiller 《Monatshefte für Chemie / Chemical Monthly》1992,123(3):265-275
Summary 4-Benzoyl-5-phenylfuran-2,3-dione (1) and the urethanes2 combine under loss of carbon monoxide yielding the open chain dibenzoylacetic acid derivatives3 and4. 3a, b only can be cyclized to the oxazinone5. The keto-enole tautomerism3 4 is further investigated with aid of semiempirical quantum chemical calculations, based upon the molecular geometry of3a, deduced from an X-ray study.
Frau Univ. Prof. Dr. Helga Wittmann mit den besten Wünschen zum 70. Geburtstag gewidmet. 相似文献
17.
K. O. Hiller B. Masloch und H. J. Möckel 《Fresenius' Journal of Analytical Chemistry》1977,283(2):109-113
Zusammenfassung Alkyldisulfide, Alkylbenzole und Alkylbromide wurden an einer chemisch gebundenen Kohlenwasserstoffphase (MicroPak-CH) mit Wasser-Methanol-Gemischen unterschiedlicher Zusammensetzung chromatographiert. In den entsprechenden Lösungsmittelgemischen wurden die SÄttigungslöslichkeiten der Probenkomponenten bestimmt. Man fand, da\ die SelektivitÄt innerhalb einer homologen Reihe durch die Löslichkeit der Glieder in der mobilen Phase bestimmt ist. Dabei lie\ sich der chromatographische KapazitÄtsfaktor mit guter Genauigkeit als k = b · (1/csat)2/3 darstellen. log k und log c
sat hÄngen linear von der C-Zahl ab.
Relation between solubility and capacity factor in the reverse-phase-bonded-phase chromatography of alkylbenzenes, alkylbromides and alkyldisulphides
Alkyldisulphides, alkylbenzenes and alkylbromides were chromatographed on a hydrocarbon type bonded stationary phase (MicroPak-CH) using water-methanol-mixtures of various composition as mobile phase. The solubility of the sample components was determined in the respective mobile phases. It was found that the selectivity within a homologous series is determined by the solubility in the mobile phase. The capacity factor can be expressed as k = b · (1/csat)2/3. Log k and log c sat depend linearly on the carbon number.相似文献
18.
The mechanism of the reaction of N-aminoethyleneimine with some aliphatic aldehydes and with acrolein have been studied. It has been shown that the reaction takes place at the carbonyl bond C=O with the formation of hydrazones.For part II, see [1]. 相似文献
19.
Falko Böttger‐Hiller Patrick Kempe Dr. Gerhard Cox Dr. Alexander Panchenko Dr. Nicole Janssen Dr. Albrecht Petzold Prof. Dr. Thomas Thurn‐Albrecht Lars Borchardt Dr. Marcus Rose Prof. Dr. Stefan Kaskel Colin Georgi Prof. Dr. Heinrich Lang Prof. Dr. Stefan Spange 《Angewandte Chemie (International ed. in English)》2013,52(23):6088-6091
20.
We analytically investigate the effect of an external mirror on the stability of an injected semiconductor laser, the latter treated as injected damped oscillators. In the studied configuration, the injected semiconductor laser with an external mirror is under the influence of a chaotic oscillating optical signal that is generated by a similar semiconductor master laser. We derive our results in terms of the damping rate and resonance frequency. We show that the external mirror can eliminate the unstable modes of the injected laser at low frequencies. Furthermore, the mirror can enhance the damping of the oscillation modes of the injected semiconductor laser; consequently, the driven response of the injected laser may have a broad spectrum, even wider than that of the chaotic driving signal. We also show results for the bandwidths of the injection amplitude and phase increment as functions of the injection rate and feedback strength of the external mirror. In addition, we use bifurcation and time-series curves to describe the dynamical behavior of the injected laser. We identify the feedback strength of injected laser, relative to that of the master laser, which induces synchronization between the injected-laser oscillation modes and the master laser. 相似文献