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81.
The metal-organic compound [Cu(MOPIP)2(OH)2] 1(MOPIP = 2-(4-methoxy-phenyl)-1H-imidazo[4,5-f][1,10] phenanthroline) was hydrothermally synthesized and structurally characterized by elemental analysis,Fourier-transformed infrared spectroscopy,thermogravimetric analysis,single-crystal X-ray diffraction and theoretical calculations in Gaussian 03.In the crystal structure,the copper(Cu) atoms are tetra-coordinated with four different nitrogen atoms from two different MOPIP ligands,and the Cu atom is one of the five vertexes of the tetrahedron.Presumably due to the steric bulk of the phenyl ligands,compound 1 adopts a slightly distorted tetrahedral configuration.Moreover,it exhibits a zero-dimensional structure with Cu-MOPIP as the building units.Natural Bond Orbital(NBO) analysis was performed by using the NBO method built in Gaussian 03 Program.The calculation results showed a covalent interaction between the coordinated atoms and Cu(Ⅱ) ion.  相似文献   
82.
范云场  张社利  陈梅兰  申屠超  朱岩 《分析化学》2010,38(12):1785-1788
以离子液体氯化1-辛基-3-甲基咪唑盐([Omim]Cl)的水溶液为萃取剂,采用加速溶剂萃取结合高效液相色谱法测定了蜜饯中苯甲酸、山梨酸、肉桂酸等有机酸类防腐剂,优化了加速溶剂萃取实验参数,最佳萃取条件为:离子液体浓度为0.1mol/L,萃取时间为5min,萃取温度为80℃。在最佳条件下,有机酸类防腐剂的检出限为0.4~27.7μg/L。将本方法用于蜜饯样品的检测,回收率为78.2%~113.9%。实验结果表明:离子液体-加速溶剂萃取法快速、高效。  相似文献   
83.
The primary goal of this paper is to price European options in the Merton's frame- work with underlying assets following jump-diffusion using fuzzy set theory. Owing to the vague fluctuation of the real financial market, the average jump rate and jump sizes cannot be recorded or collected accurately. So the main idea of this paper is to model the rate as a triangular fuzzy number and jump sizes as fuzzy random variables and use the property of fuzzy set to deduce two different jump-diffusion models underlying principle of rational expectations equilibrium price. Unlike many conventional models, the European option price will now turn into a fuzzy number. One of the major advantages of this model is that it allows investors to choose a reasonable European option price under an acceptable belief degree. The empirical results will serve as useful feedback information for improvements on the proposed model.  相似文献   
84.
In this paper we present optical and thermo-optical characterization results of integrated filters based on micro-ring resonators fabricated with a couple of polymers “PVCI/PMATRIFE”. Their high index contrast (Δn~0.15 at the wavelength of 1550 nm) allows to make small size waveguides with cross sections of 1.5×1.5 μm². The study of the impact of different gaps on the extinction ratio and FWHM (full width at half maximum) of filters leads to a better design. First experiments of thermal tunability of the microring filter using a thermo-electric cooler (TEC) are also reported giving a 5 nm shift of the dropped wavelength for a temperature change of 40 K. The fabrication of gold electrodes on microrings is reported and the electrical power required for the tuning of the drop wavelength of 0.0055 nm/1 mW show that with an optimized electrode design the consumption will be low.  相似文献   
85.
甲基咪唑甲酸盐离子液体中MMA的原子转移自由基聚合   总被引:1,自引:0,他引:1  
离子液体(Ils)是完全由正负离子组成且常温下呈液态的有机盐.离子液体几乎没有可测量的蒸汽压,具有不可燃,热容量大,热稳定性好等优点,并且对有机物,无机物,金属有机物,聚酯等均有很好的溶解能力,近几年来,在各种化学反应中,作为“绿色溶剂”使用的室温离子液体由于其独特的性质受到了越来越多的重视。  相似文献   
86.
从基尔霍夫标量式出发,在振幅零级近似和相位一级近似条件下,由Mathematica仿真计算获得微波经不同尺寸矩孔的衍射分布,并在微波光学实验仪上进行实验验证,获得了从夫琅禾费衍射向菲涅尔衍射转化的衍射花样,实验与仿真结果较为吻合。  相似文献   
87.
Brans type-I black holes is a peculiar spherically symmetric solution found in geometrized gravity theories, since the azimuthal factor of its horizon is divergent or vanishing under the classical approach of r = 2M. However, if we regard that the spherically symmetric solution is available only when all physical quantities of black holes are meaningful, then our investigation would be restricted to a special range of parameters and hence indicate a definite holographic relation to type-I black holes in Brans–Dicke theory. After that, we are able to investigate this holographic relation by making use of the brick-wall method. Drawn a comparison between the arising result and a simulated entropy formula derived from the thermodynamical evolution, a variable cut-off factor α of Brans type-I black holes is ultimately carried out.  相似文献   
88.
We study the ground-state entanglement and thermal entanglement in the hyperfine interaction of the lithium atom. We present the relationship between the entanglement and both temperature and external magnetic fields.  相似文献   
89.
应用扫描电镜观察蛛丝和蚕丝 10个样丝形态 ,并测量了这几种天然纤维的直径. 结合 X 射线光电子 能谱分析,对样丝的化学无素(氯、钾、钙、铁、硅、铬)及其含量(原子个数百分比)作了分析比较.  相似文献   
90.
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