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991.
We find that an electric current I exceeding the threshold value results in torsional strain of o-TaS3 samples with one contact freely suspended. The rotation angle deltavarphi of the free end achieves several degrees and exhibits hysteresis as a function of I. The sign of deltavarphi depends on the I polarity; a polar axis along the conducting chains (the c axis) is pointed out. We associate the effect with surface shear of the charge-density wave (CDW) coupled to the crystal shear. The current-induced torsional strain could be treated in terms of enormous piezoelectric coefficients (>10(-4) cm/V) corresponding to shear. In essence, TaS3 appears to be a ready torsional actuator based on the unique intrinsic property of the CDW. 相似文献
992.
An approach to the determination of the self-similarity parameter in the problem of converging strong shock waves is suggested. This approach allows one to obtain analytical expressions that approximate the numerical solution. For adiabatic constants gamma = 6/5-7, the values of the obtained self-similarity parameter differ by <1% from the values determined by the numerical procedure. In addition, accurate analytical characteristics of the reflected shock wave are obtained. 相似文献
993.
The band gap width in GaAs in magnetic fields of up to 10 MG is calculated using a five-band kp model. The selection rules for interband electron transitions in strong magnetic fields are found, and the dependences of the interband transition probabilities on a magnetic field are calculated. The electronic spectra calculated in the five-band model are compared with those calculated in the Kane model and in the tight-coupling approximation. The calculations are shown to agree with experimental data if the contribution from the density-of-states tails and excitonic effects to light absorption is taken into account. 相似文献
994.
995.
996.
Guralchuk GY Sorokin AV Katrunov IK Yefimova SL Lebedenko AN Malyukin YV Yarmoluk SM 《Journal of fluorescence》2007,17(4):370-376
Optical spectroscopy experiments were used to study the features of cyanine dye 3,3′-dimethyl-9-(2-thienyl)-thiacarbocyanine
iodide (L-21) aggregation in binary solutions DMF:Tris–HCl buffer (pH = 8) containing nucleic acids (DNA or RNA). The appearance
of absorption and luminescence bands associated with J-aggregates and dimers that are formed within the minor groove of DNA
has been observed. The model of L-21 J-aggregate structure is proposed. It has been found that dimers are the building blocks
of L-21 J-aggregates. Disorientation in dimers caused by the minor groove curvature is reason of observation of Davydov splitting
in absorption spectrum of L-21 J-aggregates. In the solution containing DNA the absorption and luminescence bands of L-21
J-aggregates exhibit the specific properties that allows the dye L-21 to be used as a fluorescent probe for DNA detection. 相似文献
997.
Via utilizing the mixed‐ligand method, two novel Zn(II)‐containing meta‐organic frameworks with the chemical formula of {[Zn(L)(5‐HIP)]·H2O}n ( 1 ) and [Zn(L)(2,6‐NDC)]n ( 2 ) were prepared under the solvothermal conditions by applying aromatic dicarboxylic acids ligands (5‐H2HIP = 5‐hydroxyisophthalic acid; 2,6‐H2NDC = 2,6‐naphthalenedicarboxylic acid) and 1,4‐bis(benzimidazol‐1‐yl)‐2‐butylene (L). Due to its good water stability as well as the strong luminescent emission around room temperature, complex 2 has the high selectivity and sensibility of fluorescence detection to the ceftriaxone sodium (a kind of antibiotic) with the detection limit up to ppm lever. The treatment activity of the compounds on age‐related macular degeneration was assessed and the specific mechanism was investigated. First of all, the inflammasome activation in the endothelial cells of retina was evaluated with western blot. In addition to this, the down‐stream production of the inflammasome activation was also measured with ELISA detection kit. 相似文献
998.
Sulyaeva V. S. Gatapova E. Ya. Kozhevnikov A. K. Rogilo D. I. Saraev A. A. Yushina I. V. Khomyakov M. N. Shapovalova A. A. Shayapov V. R. Bhaskar N. Tu R. Kosinova M. L. 《Journal of Structural Chemistry》2021,62(8):1309-1324
Journal of Structural Chemistry - We report a comprehensive study of the effect of the chemical structure of boron carbonitride films on the variability of their functional characteristics. The... 相似文献
999.
Rassolov A. V. Ivanov G. A. Bragina G. O. Baeva G. N. Smirnova N. S. Kazakov A. V. Usachev N. Ya. Stakheev A. Yu. 《Kinetics and Catalysis》2021,62(5):641-650
Kinetics and Catalysis - The catalytic performance of a bimetallic RhIn/SiO2 catalyst was studied in the liquid-phase hydrogenation of nitrobenzene. The formation of intermetallic Rh1In1... 相似文献
1000.
Shabatina T. I. Morozov Yu. N. Solovyov A. V. Shabatin A. V. Vernaya O. I. Fedorov V. V. Melnikov M. Ya. 《Moscow University Chemistry Bulletin》2021,76(3):196-202
Moscow University Chemistry Bulletin - A combined cryochemical method is proposed for the dimensional and structural modification of drugs. This method forms a molecular flow of a substance... 相似文献