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991.
L. Bakker  H. Khosravi 《Physica A》2010,389(6):1223-1229
To consider the psychological factors that impact market valuation, a model is formulated for investment behaviour of traders whose decisions are influenced by their trusted peers’ behaviour. The model is implemented and several different “trust networks” are tested. Simulation results demonstrate that real life trust networks can significantly delay the stabilisation of a market.  相似文献   
992.
在0.1mol/L HAc-NaAc(pH4.50)支持电解质中,淋必治(SPE)有一灵敏的示波极谱导数还原峰,峰电位Ep=-0.98V(vs.SCE)。峰电流与SPE的浓度在2.0×10^-7 ̄8.0×10^-5mol/L范围内呈线性关系,最低检出限为5.0×10^-8mol/L。该法用于注射针剂中SPE含量的测定。,结果良好。文中对SPE的极谱行为、电极过程及反应机理进行了探讨。  相似文献   
993.
大黄酚在0.15mol/L HAc-NaAc(pH4.9)底液中,出现一灵敏的示波极谱导数峰,峰电位为-0.45V(vs,SCE),峰电流与大黄酚浓度在2.0×10^-7-5.0×10^-6mol/L范围内成线性关系,检测限为2.0×10^-6mol/L。用于生药大黄中大黄酚的测定,回收率为92.4%-108.4%。用多种电化学手段研究体系的电化学行为,测得电极反应电子数n=2。体系具有吸附性,并  相似文献   
994.
ASYMPTOTICBEHAVIOUROFADIFFUSIONSYSTEMWITHTIMEDELAYINPOPULATIONDYNAMICSDingChongwen(丁崇文)(FujianEducationalCollege,福建教育学院,邮编:35?..  相似文献   
995.
Results pertaining to asymptotic behaviour of solutions of non-autonomous ordinary differential equations with locally integrably bounded right-hand sides are presented. Ramifications for weakly asymptotically autonomous systems and adaptively controlled systems are highlighted.  相似文献   
996.
层状嵌接式卟啉钴的合成,表征及其对H2O2催化降解研究   总被引:1,自引:0,他引:1  
采用有机溶剂在层状锑磷酸中在位分步分成了层状嵌接卟啉然材料;用红外光谱、紫外可见光 、X射线衍射和顺磁共振技术对其进行了表征。该合成材料对H2O2降解反应体系的进一步研究表明,卟啉钴嵌接于锑磷层状环境中对H2O2具有良好的催化降解活性和抗失活稳定性。  相似文献   
997.
The electrochemical behaviour of some hydrated layered manganese dioxides previously prepared and characterised was investigated by galvanostatic and potentiostatic studies at different conditions of temperature, type of electrolyte and counter electrode, number of cycles and depth of reduction.

Reversible range was found to be a homogeneous reaction, which is limited up to 0.23 e/f.u., whereas the major theoretical capacity is consumed in two heterogeneous reduction reactions yielding Mn(OH)2 at the end. Spinel-like phases such as hausmannite and hetaerolite are formed during the heterogeneous stage. The formation of the spinel-like phases was found to decrease at low temperature in the absence of aggressive ions such as Zn2+ and at shallow depth of reduction.

The mechanism of the electrochemical reduction of the heterogeneous stage is suggested to proceed via an intermediate with the hydrotalcite structure, which undergoes conversion to Mn3O4. The chemical reduction of manganese dioxides was also investigated and was found to support this suggestion.  相似文献   

998.
We prove a theorem on the existence and asymptotic behaviour of solutions of a differential equation with a deviating argument of neutral type. The considered equation contains both delayed and advanced arguments. The method used in the proof of our main result depends on conjunction of the classical Schauder fixed point theorem with the technique of measures of noncompactness.  相似文献   
999.
铝是地壳中含量丰富的元素 ,分布广泛 ,由于其具有价格低、能量密度高、导电性良好及无毒性等优点 ,因而是阳极材料的首选物质 ,铝电池的研究也已经成为近年来研究开发的热点课题之一[1~ 3] 。探讨铝在强碱性溶液中的溶解机理 ,对铝电池的研究和开发将具有一定的理论指导意义。1 实验部分1 1 仪器与试剂BAS 1 0 0A电化学系统 (美国BAS仪器公司 ) ;CS5 0 1型恒温槽 ;工作电极为直径是 0 .3mm的铂圆盘电极 ,参比电极是标准甘汞电极 (SCE)。铝( 99.99% ) (天津化学试剂厂 ) ,氢氧化钠为分析纯(上海化学试剂厂 ) ,水为二次蒸…  相似文献   
1000.
The self-assembly of amphiphilic cholesteryl-bearing carboxymethylcellulose derivatives (CCMCs) from individual molecules to self-aggregates, in addition to their rheological behaviour in aqueous solution were investigated. The conformations of the individual CCMC individual molecules and self-aggregates, and the microstructures of CCMC self-aggregates were characterized using the static and dynamic light scattering analyses, and the steady fluorescence technology. The results showed that the individual CCMC chains became compact, and aqueous NaCl solution changed from an approximate θ solvent to a bad one when the number of hydrophobic cholesteryl groups increased. The CCMC self-aggregates exhibited as compact spheres. The microstructural characterization indicated that one CCMC self-aggregate consisted of multiple individual CCMC molecules and hydrophobic microdomains, and multiple cholesteryl groups self-associated into one hydrophobic microdomain. The atomic force microscopy images of CCMC self-aggregates in phase mode showed that the multiple interior hydrophobic phase separation regions were surrounded by hydrophilic polysaccharide chains, providing an evidence for multiple hydrophobic microdomains in one self-aggregate. The rheological analysis proved that the CCMC self-aggregates were a microgel, in which the associations of cholesteryl groups provided multiple cross-linking points in the polymer network. The microgel solutions displayed a unique thixotropy and a shear thinning behaviour.  相似文献   
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