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951.
952.
Hiroshi Matsui Mai Nagatori Kenji Mizoguchi 《Journal of Physics and Chemistry of Solids》2010,71(4):440-443
Temperature dependence of the complex dielectric constant at 16.3 GHz has been measured on dry poly(dA)-poly(dT) DNA with Na+ counterions under different relative humidity (RH). The rotational motion of sole water dipoles hydrated in PO2− is detected at low RH, and the collective motion due to water network in major groove is successfully observed at high RH. From the infrared (IR) spectroscopy in dry DNA introducing metallic ions (M-DNA), the symmetric and antisymmetric stretching bands of PO2− distinctly depend on RH and type of metallic ions. The IR spectral change indicates that the monovalent ions (Li and Na) are arranged in PO2− though the divalent and trivalent ions connect to the base molecules. 相似文献
953.
A. Radváková O.N. Kazheva O.A. Dyachenko M. Kajňaková V.A. Starodub 《Journal of Physics and Chemistry of Solids》2010,71(5):752-757
We performed the synthesis of a (N-Me-3,5-di-Me-Py)(TCNQ)2 single crystal and we resolved the crystallic and molecular structure of this salt. Magnetic susceptibility measurements were performed in the temperature range 2-300 K. The results are studied with respect to two energy gaps in the magnetic excitations spectra which could signify that the Peierls dielectric phase forms in two grades. 相似文献
954.
Urea-succinic acid crystals have been grown at room temperature from aqueous solution in the presence of maleic acid by a slow evaporation technique. The structural parameters were determined using powder X-ray diffraction (XRD) and found to have monoclinic symmetry (space group P21/m) with a=9.902, b=17.510, c=5.555 Å and α=γ=90°, β=96.46°. The transparency and optical analysis were carried out using UV-vis analysis. The optical band gap is found to be 4.71 eV. The presence of various functional groups was confirmed by FTIR analysis. The samples have shown piezoelectric behavior with a fairly good piezoelectric charge coefficient (d33) of 5 pC/N, when it is poled at 7 kV/cm. The hysteresis loop was plotted and the remnant polarization and coercive field were found to be 2.8 μC/cm2 and 4 kV/cm, respectively. The dielectric analysis was carried out as a function of temperature at various frequencies and the results were also discussed. 相似文献
955.
The Letter reports a safe and reliable synthesis of aryl 1,2,3-triazoles from the corresponding anilines via intermediate aryl azides, using a continuous process. The method was applied to a variety of substrates with good to excellent yields, without the need to isolate the reactive and possibly unstable intermediates which were constantly kept at low concentration in the matrix environment. 相似文献
956.
957.
Mina NeghabiAbbas Behjat 《Current Applied Physics》2012,12(2):597-601
Organic light emitting diodes (OLEDs) of ITO/PEDOT:PSS/TPD:Alq3:C60/Al with different C60 concentrations (0-6.0 wt.%) have been fabricated. The physical parameters including electrical and optical properties of the samples have been measured by Luminance-current-voltage (L-I-V) characteristics and optical absorbance. The current-voltage characteristics indicate that field-emission tunneling injection dominates in the diodes at high applied voltages. It is found that with increasing the concentration of C60, the injection barrier for holes slightly reduces and the hole’s mobility increases over two orders of magnitude. Also, electroluminescence enhances with the presence of C60 in the blend; optimum current efficiency occurs at 3 wt% C60. The method provides a simple way of increasing the efficiency of OLEDs. 相似文献
958.
959.
The influence of the condensed structure of poly(styrene-co-acrylonitrile) (SAN) and traces of tetrahydrofuran(THF) that remained in titanyl phthalocyanine (TiOPc)/SAN films after fabrication on the photoconductive stability ofTiOPc/SAN composites is studied. The results reveal that the existence of traces of THF results in the increase of thephotoconductivity and the charging voltage. The main facors responsible for the unstable photoconductivity of thephotoconductors are believed to be the relaxation of SAN and the slow volatilization of THF. 相似文献
960.