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121.
Cr(III)-doped Cd(HPO4)Cl·[H3N(CH2)6NH3]0.5, a new-layered cadmium phosphate, is synthesized in acidic condition at room temperature. EPR and optical studies are carried out at room temperature. Polycrystalline EPR spectrum reveals the presence of two sites of Cr(III) ions in this layered phosphate lattice with zero-field splitting values of 24.24 and 7.65 mT, indicating that Cr(III) ions are in distorted octahedral sites. The optical absorption spectrum of the sample indicates near octahedral symmetry for the dopant ions. Crystal field, inter-electronic and bonding parameters are evaluated by collaborating EPR and optical data. The evaluated parameters suggest the mode of entry of Cr(III) ion into the layered phosphate as interstitial site, and bonding between the metal and ligand is partially covalent. 相似文献
122.
CdS and Si semiconductor nanopraticles were embedded in a polymer matrix and characterized using various techniques. The surface properties and size distribution of the nanoparticles were monitored by POM and SEM and found to be uniform but around the crystalline frameworks of the polymer. XRD and FTIR analysis have been used to ensure the composite nature and particle size of the semiconductor loaded films. The electrical conductivity of these films were evaluated and found to increase with semiconductor dispersion and attains a percolation threshold at optimum composition. This composition and the distribution of the clusters is shown to vary with the type of the semiconductor, i.e., CdS or Si. 相似文献
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建立高效液相色谱法同时测定心可舒胶囊中齐墩果酸和熊果酸的含量。采用HypersiL ODSC18(4.6mm×250mm,5μm)色谱柱;流动相:甲醇-乙腈-水=79:5:16(V/V/V);柱温:30℃;流速:1mL/min;检测波长:210nm。齐墩果酸在2.04—81.60μg/mL浓度范围内线性关系良好(r=0.9998),熊果酸在5.00—80.00μg/mL浓度范围内线性关系良好(r=0.9998),齐墩果酸的平均回收率为100.54%,RSD为1.56%,熊果酸的平均回收率为101.10%,RSD为1.13%。该法简单、准确、快捷,可用于心可舒胶囊中齐墩果酸和熊果酸的含量测定。 相似文献
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Shiro Kubuki Jun Iwanuma Kazuhiko Akiyama Akira Mikuni Tetsuaki Nishida 《Hyperfine Interactions》2012,211(1-3):173-180
In order to enhance the mechanical strength of Hagi Porcelain (Hagiyaki), one of the oldest and famous potteries in Japan, new preparation condition was examined. Tempered Hagi porcelain, denominated as ‘Hagi Porcelain B’, was prepared with the Porcelain clay originating from Daido district, Yamaguchi Prefecture, Japan. Structural change of ‘Hagi Porcelain B’ was investigated by means of 57Fe-Mössbauer spectroscopy, X-ray diffractometry (XRD) and three-point bending test. Mechanical strength of the ‘original Hagi Porcelain B’ was estimated to be 43.1 MPa by means of the three-point bending test, while much larger value of 104.5 MPa could be achieved when tempered by a chemical modification. Mössbauer spectrum of the ‘original Hagi porcelain B’ was composed of a paramagnetic doublet and a magnetic sextet due to Fe(III) of γ-Fe2O3(maghemite), while only one paramagnetic doublet due to to octahedral Fe(II)O6 was observed for the ‘tempered Hagi Porcelain B’ with isomer shift and quadrupole splitting values of 1.13 and 2.15 mm s?1, respectively. It is considered that the absence of magnetic phase causes an increase of the mechanical strength because the maghemite phase has a defect spinel structure. These results indicate that mechanical strength of the ‘Hagi porcelain B’ could be enhanced by controlling the sintering condition. 相似文献
127.
采用冲击波压缩原位光源技术结合时间分辨多波长高温计测量,研究了氟化锂和蓝宝石单晶样品的冲击消光现象,实验压力范围50~183了GPa,中心波长覆盖254~800 nm.结果表明,氟化锂单晶样品在实验压力下透过率变化不大,对界面温度的拟合值影响不明显,只是使表观发射率略有下降;当压力低于90GPa时,蓝宝石的消光情况同氟化锂接近,对界面温度的拟合影响也不明显;而当压力高于99 GPa时,蓝宝石呈现明显的消光衰减现象,实验测定的消光系数随压力增加而增加,与波长间呈反比关系,与文献报道250 0Pa高压消光特性一致.研究还发现,蓝宝石窗高压消光行为对界面温度的测量存在较大的影响,使得拟合温度明显偏低.本文研究对发展非透明材料冲击测温技术具有一定的参考价值. 相似文献
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