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981.
V. A. Zamureenko N. A. Klyuev B. V. Bocharov V. S. Kabanov A. M. Zakharov 《Chemistry of Natural Compounds》1990,25(5):549-551
The composition of the essential oil of wild bergamot bee balm introduced into the Krasnodarsk Krai has been analyzed by chromatomass spectrometry. The essential oil contains 34 components of which the main ones are -pinene (3.5%), -pinene (2.9%), -terpinene (1.7%), p-cymene (32.5), an aliphatic aldehyde (6.3%), sabinene hydrate (1.9%), -caryophyllene (1.1%), the methyl ether of carvacrol (5.5%), citronellyl acetate (1.6%), thymol (12.6%), and carvacrol (24.0%). The compounds were identified on the basis of their mass-spectrometric characteristics and arithmetical retention indices.A. N. Severtsov Institute of Animal Evolutionary Morphology and Ecology, Academy of Sciences of the USSR, Moscow. All-Union Scientific-Research Institute of Drugs, Moscow. Translated from Khimiya Prirodnykh Soedinenii, Vol. 5, pp. 646–649, September–October, 1989. 相似文献
982.
983.
R. F. Klevtsova L. A. Glinskaya V. G. Shchukin S. V. Larionov 《Journal of Structural Chemistry》2001,42(3):446-453
Volatile mixed-ligand complexes of Zn(i-Bu2PS2)2 with Phen and 2,2-Bipy have been synthesized. The crystal structures of the complexes ZnPhen{(i-C4H9)2PS2}2 and Zn(2,2-Bipy){(i-C4H9)2PS2}2 were determined by single crystal X-ray diffractometry (CAD-4 diffractometer, MoK radiation, 2100 Fhkl, R = 0.0423 for the first complex and 2003 Fhkl, R = 0.0486 for the second). The crystals are monoclinic with cell dimensions a = 17.580(4), b = 9.969(2), c = 19.175(4) , = 90.33(3)°, V = 3360(1) 3, Z = 4, d
calc = 1.313 g/cm3, space group P2/n (for the Phen complex); a = 24.219(5), b = 11.386(2), c = 24.916(5) , = 97.70(3)°, V = 6809(2) 3, Z = 8, d
calc = 1.249 g/cm3, space group C2/c (for the 2,2-Bipy complex). The complexes are constructed from discrete monomer molecules. The coordination polyhedra of the Zn atoms are distorted tetrahedra formed by two S atoms of the two monodentate i-Bu2PS
2
-
ligands and two N atoms of the cyclic bidentate Phen or 2,2-Bipy molecules. Intermolecular interactions and packings in the structures are analyzed. 相似文献
984.
测定了Pt-Sn型催化剂浸渍状态下的Sn-119、Pt-195的多核核磁共振。当SnCl2/DCl溶液体系中加入H2PtCl6以后,出现了Sn(Ⅳ)和另外一种Sn(Ⅱ)的构型,Sn-119峰向高场位移,说明部分Sn(Ⅱ)被氧化成Sn(Ⅳ),H2PtCl6的量对这种氧化性影响较小。而H2PtCl6/D2O溶液体系中加入SnCl2以后部分Pt(Ⅳ)被还原成Pt(Ⅱ),随着SnCl2量的增加,Pt(Ⅱ) 相似文献
985.
1,6-Benzodioxocane analogs of chalcones have been synthesized. From them have been obtained benzodioxocane analogs of silandrin and hydnocarpin. The PMR spectra of the substances synthesized are given and are discussed.Taras Shevchenko Kiev University, Ukraine. KIEN, Karakalpak Division, Academy of Sciences of the Republic of Uzbekistan, Nukus. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 490–493, July–August, 1994. 相似文献
986.
The kinetics of spontaneous hydrolysis of monoalkylsubstituted ketenes has been studied. The influence of inductive and steric effects of substituents upon the rate has been quantitatively estimated in terms of -analysis. Increasing length and branching of alkyl substiuents decrease the rate of ketene hydrolysis. 相似文献
987.
Iron-silicon thin films have been characterized by means of analytical transmission electron microscopic methods. Under certain conditions — composition and annealing temperature — these films exhibit thermoelectric behavior. In particular, the morphology and phase formation which results from annealing of these films, and doping with oxygen and nitrogen, are of interest. The thermoelectric phase -FeSi2 is formed at temperatures above 500°C. This phase is transformed into electrically conducting phases at about 1000°C. A small oxygen content does not influence this crystallization process. If the oxygen content is higher than 15 atom-% the electrically conducting phases exist even at 500°C. The presence of a small nitrogen content inhibits the formation of the -FeSi2 phase. The development of silicon and iron nitrides is possible. 相似文献
988.
Aromatization of methane over different Mo-supported catalysts in the absence of oxygen 总被引:2,自引:0,他引:2
Tan Pinglian Xu Zhusheng Zhang Tao Chen Liayuan Lin Liwu 《Reaction Kinetics and Catalysis Letters》1997,61(2):391-396
Both acidity and structure of the support are important factors in converting methane to aromatics. Lower SiO2/Al2O3 ratio seems to favor the aromatization of methane over the Mo/HZSM-5 catalyst. When Pt is added as a modifier the activity
of Mo/HZSM-5 catalyst will decrease slightly, but coke formation will enhanced. 相似文献
989.
Ur?ka L. ?tangar Urh ?ernigoj Polonca Treb?e Ksenija Maver Silvia Gross 《Monatshefte für Chemie / Chemical Monthly》2006,1(6):647-655
Transparent TiO2 films with a high photodegradation activity towards an azo dye in aqueous solution were prepared by sol–gel processing. Films
on soda–lime glass supports protected with a thin silica barrier layer exhibited better crystallization and monodisperse nanoparticles,
higher absorption of light below 370 nm, and higher photocatalytic activity than those films deposited on bare glass supports
proving the detrimental effect of interdiffused sodium ions on the development of the anatase nanostructure. The effect of
substrate was more pronounced in thinner films (300 nm) than in thicker ones (1200 nm), which were achieved by adding a template
(i.e. Pluronic F127) to the sol. 相似文献
990.
In this work, Ba(NO3)2 crystals with single crystal face were induced by using the the method of bio-mimetic mineralization and double LB films of behenic acid (BA) as the template. The crystals were characterized by Scanning Electron Microscope (SEM) and X-Ray Diffraction (XRD). The crystals were observed in regular square shape with uniform size about 5~8 μm by SEM, and they were found by XRD to grow along the (111) plane. From these experiments, we can conclude that the good selection of the (111) crystal face of Ba(NO3)2 is due to the electrostatic interactions , the match between this crystal face and the definite lattice structure of the LB films. 相似文献