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1.
S. A. Gurevich T. A. Zaraiskaya S. G. Konnikov V. M. Mikushkin S. Yu. Nikonov A. A. Sitnikova S. E. Sysoev V. V. Khorenko V. V. Shnitov Yu. S. Gordeev 《Physics of the Solid State》1997,39(10):1691-1695
The concentration and chemical state of copper in the subsurface region of Cu/SiO2 composite films obtained by simultaneous magnetron sputtering from two sources (Cu and SiO2) are determined by x-ray photoelectron spectroscopy (XPS). It is established that copper in the as-grown film is primarily in the form of unoxidized atoms dispersed in a SiO2 matrix. Annealing of the film results in practically no oxidation, but about 70% of the copper atoms condense into metallic clusters with sizes below 10 Å in the subsurface region and about 50 Å in the bulk of the film. The changes in the binding energy of core electrons, and especially in the energies of Auger electrons, are so large in this situation that photoelectron and Auger spectroscopy are efficient methods for monitoring the chemical state of this composite material. 相似文献
2.
The reaction of bis(hydroxymethyl)phenylphosphine with isobutyl diphenylborate in the presence of triethylamine leads to the formation of triethylammonium 2,2,5-triphenyl-1,3,2,5-dioxaborataphosphorinane (1). The reaction of compound 1 with electrophilic reagents (O, S, Se, CH2O, RHal) leads to quaternization of the phosphorus atom, giving the corresponding phosphine oxides, sulfides, and selenides and P,B-containing betaines. In the reactions of compound 1 with amines aminomethylphosphines of the diazaphosphorinane and diazadiphosphacyclooctane series are formed. Ammonium 1,3,2,5-dioxaborataphosphorinanes dissociate in solutions and enter into ion exchange with phosphonium iodides, leading to phosphonium 1,3,2,5-dioxaborataphosphorinanes. The latter, in the case of the aminomethylphosphonium cation, undergo intramolecular rearrangement with the formation of P,B-containing betaines and aminomethylphosphines.Deceased.A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan' Scientific Center, Russian Academy of Sciences, 420083 Kazan'. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 6, pp. 1398–1405, June, 1992. 相似文献
3.
Chemistry of Natural Compounds - On the basis of the NMR spectrum, a most probable structure has been proposed for the product of the sensitized photodimerization of the natural furocoumarin... 相似文献
4.
B. A. Arbuzov G. N. Nikonov I. A. Litvinov V. A. Naumov 《Journal of Structural Chemistry》1992,33(2):274-278
Organic and Physical Chemistry Institute, Kola Scientific Center, Russian Academy of Sciences. Translated from Zhurnal Strukturnoi Khimii, Vol. 33, No. 2, pp. 133–137, March–April 1992. 相似文献
5.
Katritzky AR Tymoshenko DO Monteux D Vvedensky V Nikonov G Cooper CB Deshpande M 《The Journal of organic chemistry》2000,65(23):8059-8062
The novel three-carbon synthon 1-(1H-1,2, 3-benzotriazol-1-yl)-3-chloroacetone for the synthesis of benzothiazoles, pyrido[1,2-a]indoles, and styryl-substituted indolizines and imidazo[1,2-a]pyridines is reported. The proposed routes are a general and efficient approach for heterocyclizations followed by benzannelations or attachment of arylethenyl pharmacophores. 相似文献
6.
A. S. Balueva E. I. Ayupova G. N. Nikonov Yu. T. Struchkov A. P. Pisarevskii 《Russian Chemical Bulletin》1994,43(9):1561-1567
Fused 1,3,2-dioxaborinanes, derivatives of 4-diphenylphosphino- and 4-diphenylphosphoryl-4H-1, 3-dioxa-2-boraphenanthrenes, and their complexes with amines have been synthesized. According to X-ray diffraction data, the complex of 2-phenyl-4-diphenylphosphoryl-4H-1, 3-dioxa-2-boraphenanthrene with butylamine exists as a dimer due to the formation of intermolecular hydrogen bonds.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1649–1655, September, 1994.The present work was financially supported by the International Science Foundation (grant No. RHBOOO). 相似文献
7.
The action of ultra violet rays of 260 nm on aqueous solutions of bases, nucleosides and nucleotides of DNA at 77°K is studied by electron spin resonance. It is shown that the free radicals observed are similar, with a few noteworthy exceptions to those induced by X-rays, under the same conditions of temperature, in the solid state. Contrary to what might be excepted on the basis of the results obtained by X-rays, the variation in the yield in paramagnetic centres in each sequence studied does not seem to be important. 相似文献
8.
ALBERT VAN DE VORST 《Photochemistry and photobiology》1971,13(4):321-336
Abstract— –The photosensitization of amino acids by proflavine is studied using the technique of electron spin resonance spectroscopy. The analysis of the line shape as a function of the incident microwave power (both in the presence and absence of oxygen) and the dependence of the numbers of free radicals on the intensity of the incident light allow one to suggest that two types of radicals are formed. One is formed by a biphotonic process, the nature of the radicals being the same as in the case of ionising radiation, while the other is probably the RO2 radical formed as a result of photodynamic action. 相似文献
9.
10.
Summary From the roots ofFerula korshinskyi Eug. Kor. we have isolated a new ester with the composition C22H34O5, []
D
23
–29° (c 0.94; chloroform) n
D
24
1.491, bp 42°C/8 mm Hg, which we have called fekorin. On the basis of a study of the products of hydrolysis and also spectral characteristics, it has been established that fekorin is 8-acetoxy-6-angeloyloxy-9,10-epoxygermacr-3-ene.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 152–155, March–April, 1975. 相似文献