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1.
2.
L. N. Luk’yanova V. A. Kutasov V. V. Popov P. P. Konstantinov 《Physics of the Solid State》2006,48(4):647-653
The galvanomagnetic and thermoelectric properties of n-Bi2-x SbxTe3-y-z SeySz multicomponent solid solutions with atomic substitutions (Sb → Bi; Se, S → Te) are studied. The principal components of the effective mass tensor (m 1, m 2, m 3) for the isotropic mechanism of charge carrier scattering are determined within a many-valley model of the energy spectrum for compositions 0.08 ≤ x ≤ 0.4 and 0.06 ≤ y = z ≤ 0.15. The effect of a variation in the parameters of the constant-energy surface on the thermoelectric efficiency is analyzed for different compositions and carrier concentrations in solid solutions. 相似文献
3.
4.
R. Mateva Ch. Konstantinov V. Kabaivanov 《Journal of polymer science. Part A, Polymer chemistry》1970,8(12):3563-3575
The influence of the acidity of organoaluminum compounds and their complexes on the catalytic activity in polymerization of trioxane has been studied. It is found that the catalytic activity of organoaluminum compounds of the type RnALX3?n depends on n as well as the nature of R or X. Catalytic activity of the complexes also depends on the type of cocatalyst used. The change of electroconductivity in the course of formation of some initiator complexes has been studied and an attempt has been made to determine the relation between conductivity and polymerization activity. 相似文献
5.
I. O. Konstantinov B. V. Zatolokin N. N. Krasnov Yu. G. Sevastyanov L. S. Volkova 《Journal of Radioanalytical and Nuclear Chemistry》1976,31(2):487-493
Procedures for determining traces of calcium, titanium, vanadium, chromium, iron, copper, niobium, molybdenum and tungsten
in tantalum are described utilizing 11 MeV proton activation. The instrumental method of analysis with the use of a Ge(Li)
detector and the radiochemical separation of the corresponding fractions are described. The formula for the calculation of
the concentration of traces with the use of thick target yields is given. Experimental data on the thick target yields of
radioisotopes44Sc,52Mn,56Co,65Zn,93mMo,96Tc are presented. Based on the experimental data, the detection limits are estimated at 1–10 ppb for the above mentioned metal
traces in tantalum. The successful solution of the task of the simultaneous determination of nine elements in tantalum confirms
the wide applicability of proton activation analysis. 相似文献
6.
The phase behavior and structure of liquid-crystalline homo-and copolymers based on structurally isomeric units belonging to the family of phenyl benzoates that differ in orientation of an ester link situated between benzene rings have been studied with X-ray diffraction, scanning calorimetry, and polarization optical microscopy. The orientation of this link in the monomer unit affects the temperature of phase transition, the type of the smectic phase, and the packing mode of side mesogenic groups in smectic layers of homopolymers. When monomer units commensurable with the monomer units of the basic component in terms of geometry but not identical to them in terms of smectogenity are randomly incorporated into macromolecules of the LC polymer, the resulting copolymer is characterized by layered packing not typical of either of the components. 相似文献
7.
P. A. Konstantinov T. V. Shchedrinskaya I. V. Zakharov 《Chemistry of Heterocyclic Compounds》1972,8(12):1454-1454
Selenophene-2,5-dicarboxylic acid was obtained by liquid-phase oxidation of 2,5-dimethylselenophene with molecular oxygen.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, p. 1605, December, 1972. 相似文献
8.
M. M. Kabachnic E. V. Zobnina V. Yu. Pavlov I. O. Konstantinov G. V. Ponomarev I. P. Beletskaya 《Russian Chemical Bulletin》2005,54(1):262-265
A preparative procedure is proposed for the synthesis of α-aminophosphonates of natural porphyrins by the microwave-assisted Kabachnik—Fields reaction.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 256–259, January, 2005. 相似文献
9.
V. Yu. Pavlov I. O. Konstantinov G. V. Ponomarev V. P. Timofeev B. G. Kimel' 《Russian Journal of Organic Chemistry》2005,41(12):1824-1835
The vinyl groups in protoporphyrin IX and chlorophyll a derivatives were selectively transformed into hydroxymethyl and acetoxymethyl substituents. The reactivities of β-hydroxymethyl and β-acetoxymethyl groups in porphyrins and chlorins toward nucleophilic reagents were compared for the first time using the reaction with acetylacetone as an example. Peripheral acetylacetone moieties in porphyrins and chlorins were shown to be promising as building blocks for generation of exo heterocyclic structures. 相似文献
10.
G. M. Beladidze S. I. Bityukov G. V. Borisov Yu. P. Gouz R. I. Dzhelyadin Yu. M. Ivanyushenkov A. N. Karyukhin I. A. Kachaev G. A. Klyuchnikov V. F. Konstantinov M. E. Kostrikov V. V. Kostyukhin A. A. Kriushin Yu. A. Khoklov V. V. Lapin T. A. Lomtadze V. D. Matveyev V. A. Medovikov V. F. Obraztsov A. P. Ostankov D. I. Ryabchikov V. K. Semenov E. A. Starchenko N. A. Shalanda E. G. Tskhadadze N. K. Vishnevsky E. V. Vlasov V. I. Yakimschuk A. M. Zaitsev S. A. Zimin 《Zeitschrift fur Physik C Particles and Fields》1992,54(2):235-238
The reaction
–
C
–
C has been studied at 36 GeV/c. A clear signal for the decaya
2
–
(1320)
–
· is observed in the
–
mass spectrum. The measured ratio of branchings is BR (a
2
–
–
)/BR(a
2
–
–
);(3.4±0.8±0.5)·10–2. 相似文献