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61.
The TDDFT method is first applied in a series of tetra-nuclear transition metal clusters studies for nonlinear optical properties. The results indicate that the charge transfer inside the metal core [MCu3X4] (M=W, Mo; X=S, O, Cl, Se, Br) makes contribution to the optical nonlinearity. It is possible to enhance the hyperpolarizability by substituting the ligands of the clusters. 相似文献
62.
Chemical characterisation has been carried out on 25 quarry marbles collected from Marmara, Aegean and Thrace regions of Turkey. Ten elements were determined by capillary electrophoresis (CE). Principal component analysis and cluster analysis techniques were utilised to define grouping of different marble samples. These techniques showed that the analysed marbles were differentiable mainly by provenance. Experimental conditions such as pH, applied voltage and concentration of α-hydroxyisobutyric acid (HIBA) were optimised to achieve the best separation of metal ions using central composite design. The optimum pH 3.7, applied voltage 15 kV and concentration of HIBA 10 mM were found to provide the best separation for all metal ions investigated. 相似文献
63.
Yu-Ming ZHENG Hong-Min LIU Ben-Hao SA Zhong-Dao LU Zhong-Qi WANG Xiao-Ze ZHANG 《理论物理通讯》1993,19(1):71-74
A simple Monte Carlo simulation and even a partition method can be used to reproduce quite well the power law behavior between the factorial moment and the charge interval of fragment charge distributions from the multifragmentation of 197Au nucleus bombarding emulsion at~1 GeV/nucleon. This indicates that the above power law seems not to be a unique precursor of the intermittent behavior in nuclear multifragmentations. 相似文献
64.
The charge dispersion of fragments in high energy p+Cu,Kr and Xe reactions are calculated by statistical model and Monte Carlo technique.The corresponding data are reproduced quite well.It is shown that the charge dispersions are all nearly gaussian.The mass dependence of the most probable fragment charge reflects the rest target memory effect. 相似文献
65.
Following the method developed by the authors,recently,the equation of state of hot nuclei(238U in concrete) before break-up was investigated numerically.The isotherms are drawn in the plan of the general pressure P versus volume VRT. They are similar to those of Van der Waals gas.The critical temperature of phase transition should correspond to the isotherm with one turning point only.It turns out that the data of mass yield distribution can be reproduced by many pairs of parameters T and VRT (freeze-out temperature and freeze-out volume) varying in certain range.For each isotherm (each T),the data are always best reproduced by the value of VRT located at the maximum general pressure within two phases coexistence region. 相似文献
66.
67.
LU ZhongDao SA BenHao Masanori Matsuda Junichi Nagata Atsushi Nakamura Osamu Miyamura 《中国物理C(英文版)》2000,24(8):743-747
The Λ multiplicity and Λ/p ratio are studied by hadron transportation-string fragmentation model in relativistic heavy ion collisions. Firstly, the dependence of Λ multiplicity and Λ/p ratio on the system size and the collision centrality is studied. It shows that the Λ and p multiplicities go up as the increase of system size and the increase of collision centrality. However, their ratio keeps almost a constant. The effect of Λ annihilation cross section to Λ multiplicity and Λ/p ratio is also studied. It is found that this effect is weak: Λ multiplicity and Λ/p ratio have a little amount of increase by the decrease of Λ annihilation cross section. Even the cross section is down to zero, Λ/p ratio is only 1.2 in 200A GeV AuAu head on collision. The Λ/p ratio is obtained to be 0.28 in pp collision, lying in the range of experimental data:0.2—0.3. It is also obtained that the ratio in AA collisions is 3—5 times of that in pp collision. 相似文献
68.
69.
MB-硬脂酸复合薄膜光波导传感器检测氯化氢气体 总被引:1,自引:0,他引:1
利用旋转甩涂法将亚甲基蓝(MB)掺杂的硬脂酸溶液涂成薄膜固定在钾离子(K+)交换玻璃光波导表面上, 研制了MB-硬脂酸复合薄膜/K+交换玻璃光波导传感器, 并对酸性气体进行了检测. 该复合薄膜与氯化氢(HCl)气体作用时, 薄膜颜色从深蓝色变为浅蓝色, 导致薄膜对倏逝波的吸收降低, 使传感器的输出光强度增强. 结果表明, 在室温下该传感器对低浓度的氯化氢气体仍具有较好的重复性和选择性响应, 可检测到体积分数为1×10-6%的HCl气体, 响应和恢复时间分别为7和20 s, 相对标准偏差为±6.06%. 该传感器具有灵敏度高、 响应-恢复速度快、 可逆性好、 成本低和容易制备等特点. 相似文献
70.
Lian HZ Kang YF Yasin A Bi SP Shao DL Chen YJ Dai LM Tian LC 《Journal of chromatography. A》2003,993(1-2):179-185
Morin was used as a pre-column reagent for the determination of aluminum by RP-HPLC with fluorescence detection. This method has been successfully applied to direct determination of trace Al in environmental and biological samples. The response was linear from 6 x 10(-9) to 6 x 10(-5) M with a detection limit of 2 x 10(-9) M. In addition, the different Al complexes with morin were separated by the proposed HPLC procedure and their coordination ratios were depicted by molar-ratio method. The results showed that 1:1 and 2:1 Al-morin complexes formed. 相似文献