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951.
952.
The mixed-quadriligand bismuth complex [Bi(S2CNEt2)2(NO3)]([1,10-Phen] has been synthesized, and its crystal structure was determined by X-ray single-crystal diffraction. The crystal belongs to monoclinic, space group P21/n with a = 10.074(17), b = 15.05(2), c = 18.99(3)(°A), β = 98.85(3)o, V = 2845(8)(°A)3, Z = 4, F(000) = 1464, Dc = 1.746 g/cm3, μ = 6.523 mm-1, R = 0.0333 and wR = 0.0703. In this complex, the bismuth atom is eight-coordinated in a capped distorted pentagonal bipyramidal geometry. 相似文献
953.
D. Nataraj K. Senthil Sa. K. Narayandass D. Mangalaraj 《Crystal Research and Technology》1999,34(7):867-872
Thin films of Bi2Se3 have been prepared by vacuum deposition technique onto well cleaned glass and freshly cleaved KBr substrates. The film thicknesses are measured by Tolansky technique. The capacitance and dielectric constant have been measured from 303 K to 383 K in the frequency range of 10 kHz to 10 MHz. The a.c. conductivity s is calculated at different frequencies for various temperatures. The relation s μ wn fits well and the value of n is found to be greater than 1.5 and above at high frequencies suggests that the conduction mechanism in Bi2Se3 thin film is hopping. The d.c. conduction studies revealed the non-ohmic type of conduction( Log I versus Log V plot). From the Log I versus F1/2 plot, the field lowering coefficient b is evaluated. 相似文献
954.
955.
流动注射-氢化物发生-原子吸收光谱法测定胃必治中铋 总被引:4,自引:0,他引:4
采用流动注射(FI)、氢化物发生(HG)、原子吸收光谱(AAS)联用的方法,考察了各试验参数对测定抗酸药胃必治中铋的影响。方法具有分析速度快、样品用量少、灵敏度高、选择性强等特点。用于实际样品的分析,结果满意。 相似文献
956.
957.
Ferroelectric Films 总被引:1,自引:0,他引:1
Uhlmann D.R. Dawley J.T. Poisl W.H. Zelinski B.J.J. Teowee G. 《Journal of Sol-Gel Science and Technology》2000,19(1-3):53-64
The preparation and properties of ferroelectric films are reviewed. Specific attention is directed to ferroelectric films prepared by wet chemical methods. Emphasis is placed on the microstructure and properties of SBT films for memory applications, and their dependence on chemistry and processing, as well as on the effects of chemistry and processing on the properties of piezoelectric and pyroelectric films. Emphasis is placed on recent results obtained in our laboratories, including modeling of the ferroelectric behavior of films and experimental results in each of these areas. Also considered is the use of ferroelectric films in memory, piezoelectric and pyroelectric devices of various types, with specific note made of the recently-announced use of pyroelectric sensors in automobiles. 相似文献
958.
D. M. Lin D. Q. Xiao J. G. Zhu P. Yu H. J. Yan L. Z. Li W. Zhang 《Crystal Research and Technology》2004,39(1):30-33
Bismuth sodium titanate (abbreviated as BNT) based solid solution, [Bi0.5(Na1‐x‐yKxLiy)0.5]TiO3 (0 < x + y < 1) ceramics, was invented in our group. These ceramics, which are considered as new candidates for lead‐free piezoelectric materials, were prepared by conventional ceramic sintering technique. The results of X‐ray diffraction show that the ceramics possess a single perovskite phase. The relations of the sintering conditions and the microstructures of the ceramics were studied. It was found that the optimized sintering condition is at 1100‐1150 °C for 2‐3 h, the grains of the ceramics have very regular shape, and the grain size of the ceramics is in the range of 1.3‐2.2 μm. These ceramics with the compositions of high amount of K+ and low amount of Li+ have relatively large piezoelectric charge constant (d33), and can be put into practical applications. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
959.
960.