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151.
We study the one-loop quantum corrections for higher-derivative superfield theories, generalizing the approach for calculating the superfield effective potential. In particular, we calculate the effective potential for two versions of higher-derivative chiral superfield models. We point out that the equivalence of the higher-derivative theory for the chiral superfield and the one without higher derivatives but with an extended number of chiral superfields occurs only when the mass term is contained in the general Lagrangian. The presence of divergences can be taken as an indication of that equivalence. 相似文献
152.
A. B. Shishmakov Yu. V. Mikushina O. V. Koryakova M. S. Valova S. Yu. Men’shikov L. A. Petrov 《Russian Journal of Applied Chemistry》2011,84(9):1555-1559
Fundamental aspects of the synthesis of 2,3,5-trimethylbenzoquinone by oxidation of 2,3,6-trimethylphenol adsorbed on the
surface of a titanium dioxide xerogel and on TiO2 modified with powdered cellulose with hydrogen peroxide without any organic solvent involved in the process were studied. 相似文献
153.
154.
Electrically charged (up to 107 e) macroscopic superconducting particles with sizes in the micrometer range confined in a static magnetic trap in liquid nitrogen and in nitrogen vapor at temperatures of 77–91 K are observed experimentally. The macroparticles with sizes up to 60 μm levitate in a nonuniform static magnetic field B ~ 2500 G. The formation of strongly correlated structures comprising as many as ~103 particles is reported. The average particle distance in these structures amounts to 475 μm. The coupling parameter and the Lindemann parameter of these structures are estimated to be ~107 and ~0.03, respectively, which is characteristic of strongly correlated crystalline or glasslike structures. 相似文献
155.
The oscillatory motion of electrons in a periodic potential under a constant applied electric field, known as Bloch oscillations (BO), is one of the most striking and intriguing quantum effects and was predicted more than eighty years ago. Oscillating electrons emit electromagnetic radiation and here we consider this BO effect for emission in the THz region. To date, it has been assumed that the Bloch oscillation of an electron is anharmonic oscillation, therefore with radiation emitted at the single Bloch frequency. We analyze scenarios when Bloch oscillations can be accompanied by the emission of radiation not only at the Bloch frequency but also with double and triple Bloch frequencies. The first scenario means that electrons could jump over neighboring Stark states. The second scenario of anharmonic emission is coupled to an opening of the minigap in the miniband. 相似文献
156.
T. A. Danilova A. N. Korepanov S. N. Petrov 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2):71-72
Abstract It is established that isometric butenyl phenyl sulfides on chromic catalysts yield mainly direct cyclization products unlike their reactions on heterogenous acidic catalysts previously investigated in our laboratory. In the presence of such catalysts the formation of cyclic comcounds proceeds in different ways depending on the position of the side-chain double bond. In case chromic catalysts are used the mentioned factor affects only the easiness of cyclization, but not the nature of the process as such. 相似文献
157.
A. A. Kaunova V. I. Petrov T. G. Tsyupko Z. A. Temerdashev V. V. Perekotii A. A. Luk’yanov 《Journal of Analytical Chemistry》2013,68(9):831-836
We have estimated the possibility of identifying the provenance of some natural wines produced in the Krasnodar region. The macro- and microelement composition of wines and soils from the place of grape origin has been used as the classification criterion. The main elements indicating the wine provenance, Al, Co, Cu, Mn, Ti, Zn, Ba, and Rb have been determined by inductively coupled plasma atomic emission spectroscopy. We have revealed the possibility of distinguishing wines by their brand and provenance using pair-wise comparison of the classification function parameters for soils and wines produced from grape grown on those soils. 相似文献
158.
A. B. Shishmakov M. S. Molochnikov D. O. Antonov O. V. Koryakova A. S. Seleznev L. A. Petrov 《Russian Journal of Applied Chemistry》2013,86(3):297-303
A Cu(II)-containing binary xerogel TiO2-SiO2 was synthesized by joint hydrolysis of tetrabutoxytitanium, teraethoxysilane and copper(II) chloride dissolved in their mixture. The synthesis was performed in a vapor of 10% aqueous ammonia under static conditions. EPR spectroscopy was used to examine the state of Cu(II) in the xerogel matrix. Data on specific features of the behavior of saccharose within xerogel pores under heating were obtained. The catalytic activity of the xerogel was tested by the kinetic method on model reactions of hydrogen peroxide decomposition and oxidative dehydrogenation of trimethylhydroquinone. 相似文献
159.
The state of tetra(5-tert-butylpyrazino)porphyrazine, octaethyltetrapyrazinoporphyrazine, octaphenyltetrapyrazinoporphyrazine in DMSO medium was studied. It was found that the complexes formed with the proton transfer exhibit a relatively high stability. In strong basic media these complexes are kinetically unstable. The influence of the nature of cyclic and acyclic nitrogen-containing bases, as well as the influence of NH-acidity of the porphyrazine macrocycle on the rate and activation parameters of decomposition of the proton-transfer complexes of tetra(5-tert-butylpyrazino)porphyrazine, octaethyltetrapyrazinoporphyrazine, and octaphenyltetrapyrazinoporphyrazine was established. 相似文献
160.
Anatoli Tchigvintsev Dmitri Tchigvintsev Robert Flick Ana Popovic Aiping Dong Xiaohui Xu Greg Brown Wenyun Lu Hong Wu Hong Cui Ludmila Dombrowski Jeong Chan Joo Natalia Beloglazova Jinrong Min Alexei Savchenko Amy A. Caudy Joshua D. Rabinowitz Alexey G. Murzin Alexander F. Yakunin 《Chemistry & biology》2013,20(11):1386-1398
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