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961.
Enzyme-catalyzed reaction of o-phenylenediamine (OPD)-Hz02-horseradish peroxidase (HRP) voltammetric enzyme-linked immunoassay system has been studied in detail with electrochemical analysis, high performance liquid chromatography (HPLC), ultraviolet/visible (UV/Vis) spectroscopy, infrared (IR) spectroscopy and nuclear magnetic resonance (NMR) spectroscopy. The pure product of H202 oxidizing OPD catalyzed by HRP was prepared with chemical method. The experimental results of voltammetry and HPLC indicate that only one product of enzyme-catalyzed reaction has been obtained under the selected enzyme-catalyzed reaction conditions. Identifications by UV/ Vis spectrum, IR spectrum and13C NMR spectrum show that the product is 2,3-diaminophenazine. The processes of the enzyme-catalyzed reaction and the electroreduction of the product of the enzyme-catalyzed reaction are described. Project supported by the National Natural Science Foundation of China  相似文献   
962.
提出一种新的诊断飞秒脉冲振幅与位相的高精度测量方法.该方法发展了传统的SPIDER方法,保留了原方法对脉冲信息可以实时、有效和全面地测取的优点,并能克服其不能测量脉宽较大或位相信息复杂的脉冲的缺点.在新方法中和频后的脉冲对没有相对延时,形成无干涉条纹的剪切干涉图.在调节一个小量延时于某些特定值,可去掉剪切干涉图的歧义性.给出数值模拟结果,证明此方法无需经过傅里叶变换滤波,可直接由干涉图唯一地提取出脉冲的振幅与位相信息. 关键词: 光谱位相相干直接电场重构法 飞秒脉冲测量 超快信息光学  相似文献   
963.
Optical polarization properties of aluminum, gold and aluminum/gold subwavelength metallic gratings (SWMGs) are investigated numerically in the visible light band. Their performance as polarizing beam splitters are simulated with RCWA for varied metallic materials, grating depth and incident angle. Metallic waveguide theory is applied to explain the performance difference between Au and Al grating. A new type of Al/Au bimetallic is also investigated numerically for potential applications. PACS 42.79.Dj; 42.81.Gs; 73.20.Mf  相似文献   
964.
We give a good characterization of the permutation polynomials in two variables over Z/p2Z.  相似文献   
965.
Based on the D6d-symmetrical C24H24 fullerene, its derivatives, which have been exohedrally functionalized by replacing one of its H atoms with –CH2OH, –CONH2, –COOH, and –COH, have been firstly calculated using the hybrid DFT-B3LYP functional in conjunction with 6-31G(d) basis sets. Present calculations show that the C24H23(COOH) is the most stable under the values of ΔH and De. The calculated HOMO–LUMO energy gaps of the derivatives with –CH2OH and –COOH groups are same as in the case of the not functionalized C24H24 cluster. In addition, the C24H23(CONH2) displays the largest dipole moment (3.32 D), and the vertical electron affinities of the functionalized derivatives are all very higher. These can promote new development in the fields of the bio-medical applications.  相似文献   
966.
陈卫平  冯尚申  焦正宽 《物理学报》2003,52(12):3176-3180
采用磁控溅射法分别在玻璃和单晶硅衬底上同时制备了Fe15.16Ag84.84金属颗粒膜样品,并对样品的霍尔效应和霍尔系数RH随外加磁场H的变化关系进行了 实验研究. 观察到霍尔电压UH与外加磁场H的关系曲线呈现出自旋极化相关的反常现象,并 与其磁电阻效应具有对应关系.基于自旋相关的散射理论对此作出了合理的解释. 关键词: 颗粒膜 霍尔效应 c')" href="#">特征磁场Hc 自旋相关散射  相似文献   
967.
This paper presents an algorithm for finding a global minimum of a multimodal, multivariate and nondifferentiable function. The algorithm is a modification to the new version of the Price’s algorithm given in Brachetti et al. [J. Global Optim. 10, 165–184 (1997)]. Its distinguishing features include: (1) The number-theoretic method is applied to generate the initial population so that the points in the initial population are uniformly scattered, and therefore the algorithm could explore uniformly the region of interest at the initial iteration; (2) The simplified quadratic approximation with the three best points is employed to improve the local search ability and the accuracy of the minimum function value, and to reduce greatly the computational overhead of the algorithm. Two sets of experiments are carried out to illustrate the efficiency of the number-theoretic method and the simplified quadratic model separately. The proposed algorithm has also been compared with the original one by solving a wide set of benchmark problems. Numerical results show that the proposed algorithm requires a smaller number of function evaluations and, in many cases, yields a smaller or more accurate minimum function value. The algorithm can also be used to deal with the medium size optimization problems.  相似文献   
968.
成鹏飞  李盛涛  焦兴六 《物理学报》2006,55(8):4253-4258
研究了ZnO-Bi2O3系压敏陶瓷等效势垒高度eff随着归一化电压的变化规律,发现等效势垒高度eff随着归一化电压的增加先逐渐增大,达到最大值后持续下降.由于在外加电压作用下反偏势垒高度高于正偏势垒高度,等效势垒高度eff主要取决于反偏势垒.因此,这种变化规律说明了ZnO压敏陶瓷晶界的导电过程可能存在三个阶段.在低归一化电压区,晶界区域中的电子从正偏势垒区注入到晶界无序层的速率低于电子从晶界无序 关键词: ZnO压敏陶瓷 归一化电压 等效势垒高度 导电过程  相似文献   
969.
The general properties of one-dimensional large Fr?hlich polarons in motion are investigated with the previous extended coherent states where two-phonon correlations are considered. As a result, the polaron energy, velocity, effective mass, and average number of virtual phonons as a function the polaron total momentum are evaluated in a wide range of the coupling constant. In addition, rich information about virtual phonons emitted by the electron in motion is obtained. More importantly, some intrinsic features of 1D moving polarons are presented for the first time, which may also be suited to moving polarons in more than one dimensions. Received: 23 October 1997 / Revised and Accepted: 27 January 1998  相似文献   
970.
By using of the invariant theory, we have studied the phase of two-body Bose-Einstein condensates with collision, the dynamical and geometric phases are presented respectively. The Aharonov-Anandan phase is also obtained in the case of considering the cyclical evolution.  相似文献   
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