排序方式: 共有46条查询结果,搜索用时 15 毫秒
1.
Gabriela Ionita Petre Ionita Victor EM. Sahini Constantin Luca 《Journal of inclusion phenomena and macrocyclic chemistry》2001,39(3-4):269-271
The kinetics of oxidation of amino acids (Arg, His, Lys, Phe, Thr and Tyr), a dipeptide (Gly-His), and BSA (bovine serum albumin) by two persistent water soluble free radicals of the hydrazyl type has been studied.The rate decreases in the order Arg>Lys>Tyr>Thr>HisBSAPheGly-His with bothfree radicals. Addition to the reaction mixture of - and -cyclodextrin decreases the oxidation rate, probably due to amino acidencapsulation in the cyclodextrin cavity. -Cyclodextrin protects more efficiently against oxidation than -cyclodextrin. 相似文献
2.
A. N. Polyakov M. Noltemeyer T. Hempel J. Christen M. A. Stepovich 《Bulletin of the Russian Academy of Sciences: Physics》2012,76(9):970-973
The use of time-of-flight cathodoluminescence measurements in the studies of semiconductor samples partially covered with a light-absorbing mask of special geometry in order to obtain new quantitative information about the properties of materials is shown. The values of the exciton diffusion coefficient are determined from the results obtained in an experimental study of gallium nitride. 相似文献
3.
M. N. Shipko A. I. Tikhonov M. A. Stepovich A. A. Viryus T. P. Kaminskaya V. V. Korovushkin E. S. Savchenko I. V. Eremin 《Bulletin of the Russian Academy of Sciences: Physics》2018,82(8):988-992
The effect of magneto-pulse processing on the microstructure and magnetic behavior of amorphous electrotechnical steel is studied. It is found that the directed ordering of Fe atoms helps to increase specific magnetization of saturation and the coefficient of the squareness of the hysteresis loop, and is related to ordering of the spin system. 相似文献
4.
T. A. Kupriyanova L. R. Minikaev R. R. Tangishev M. A. Stepovich M. N. Filippov 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2013,7(2):268-270
A method is proposed for calculating the relative range of electrons in the material with low conductivity, which surface is coated by a conductive film. The method takes into account the average retarding electric field of spatial charge created in the material. The calculations were carried out using the classical generalized Widdington’s law of slowing down within the model of single-collision loss. Due to the approximations used, the calculations have a qualitative character. 相似文献
5.
M. G. Snopova N. N. Mikheev V. I. Petrov M. A. Stepovich 《Bulletin of the Russian Academy of Sciences: Physics》2008,72(11):1451-1455
Some new possibilities of modeling the dependences of the monochromatic cathodoluminescence intensity on the electron beam energy for a three-layer direct-gap semiconductor structure (where the diffusion of minority charge carriers can be described within the independent-source model) are considered. 相似文献
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7.
We have used a variety of microscopic techniques to reveal the structure and motion of flux line arrangements, when the flux
lines in low T
c type II superconductors are caused to move by a transport current. Using small-angle neutron scattering by the flux line
lattice (FLL), we are able to demonstrate directly the alignment by motion of the nearest-neighbor FLL direction. This tends
to be parallel to the direction of flux line motion, as had been suspected from two-dimensional simulations. We also see the
destruction of the ordered FLL by plastic flow and the bending of flux lines. Another technique that our collaboration has
employed is the direct measurement of flux line motion, using the ultra-high-resolution spectroscopy of the neutron spin-echo
technique to observe the energy change of neutrons diffracted by moving flux lines. The muon spin rotation (μSR) technique gives the distribution of values of magnetic field within the FLL. We have recently succeeded in performing
μSR measurements while the FLL is moving. Such measurements give complementary information about the local speed and orientation
of the FLL motion. We conclude by discussing the possible application of this technique to thin film superconductors. 相似文献
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A. G. Khokhlov R. R. Valiullin J. Kärger N. B. Zubareva M. A. Stepovich 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2008,2(6):919-922
Certain possibilities of scanning electron microscopy and cryoporometry based on nuclear magnetic resonance (NMR) have been evaluated to determine pore sizes in porous silicon. The results obtained by these methods have been compared. NMR cryoporometry has been shown to be promising in the investigation of porous materials. 相似文献
10.
Petrov GI Shcheslavskiy VI Yakovlev VV Golovan LA Krutkova EY Fedotov AB Zheltikov AM Timoshenko VY Kashkarov PK Stepovich EM 《Optics letters》2006,31(21):3152-3154
Anisotropic photonic crystal structures consisting of birefringent porous silicon layers with alternating porosity were fabricated. The in-plane birefringence formed as a result of anisotropic etching in Si(110) results in unique multilayered structures with two distinct photonic bandgaps for orthogonal light polarizations. Nonlinear optical studies based on the third-harmonic generation from these structures demonstrate variation in the symmetry of the nonlinear optical response. 相似文献