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51.
52.
Wang C Xu J Zhou G Qu Q Yang G Hu X 《Combinatorial chemistry & high throughput screening》2007,10(7):547-554
Recent advances in electrochemical detection techniques coupled with high-performance liquid chromatography (HPLC-ECD) in pharmaceutical and biomedical analysis are reviewed. ECD classification and modes including common amperometric, coulometric, conductimetric, and potentiometric detector, are outlined and the some typical examples of determinations in pharmaceutical and biomedical analysis are described. The electrochemical detection system can offer superior merits over other detectors commonly used with HPLC. These techniques have great potential owing to their prominent characteristics in high-throughput screening procedures of drugs in various matrices. Fundamental 67 references from last 5 years related with a field are cited in this review. 相似文献
53.
考虑混凝土应变率变化的高拱坝非线性动力响应研究 总被引:3,自引:0,他引:3
提出一种新的应变率相关的混凝土非线性弹塑性损伤模型。采用此模型对混凝土拱坝的非线性地震响应作了分析。在综合考虑坝-地基-库水动力相互作用和坝缝非线性接触的基础上,着重研究了混凝土应交率相关效应及加载历史对混凝土极限强度等重要参数及拱坝响应的影响,并与采用不考虑应交率影响的混凝土损伤模型计算结果进行了对比分析。结果表明,拱坝考虑横缝作用后的坝面应变率分布不同于整体拱坝。应交率分布形态不仅可以很好地表征拱坝的振动形态,而且对于高拱坝的动力响应的影响也不可忽略。 相似文献
54.
本文针对核磁共振仪的隔离问题,提取非线性随机振动理论模型,在FPK方程中对系统的参数进行了优化,用统计线性化方法计算响应;用非线性隔离系统传递率的定义计算隔振效果,最后对隔离装置进行了实验分析和信号处理,并对理论计算与实验结果进行了对比. 相似文献
55.
Dan Xu Lin Liu Jun Guan Jianyun Xu Ting Wang Aijian Qin Xiaoya Hu Chengyin Wang 《Mikrochimica acta》2014,181(3-4):403-410
We report on label-free immunosensors for the highly sensitive detection of avian influenza virus. The method makes use of the microcantilevers of an atomic force microscope onto which monoclonal antibodies against avian influenza virus were covalently immobilized. The factors influencing the performance of the resulting immunosensors were optimized by measuring the deflections of the cantilever via optical reflection, and this resulted in low detection limits and a wide analytical range. The differential deflection signals revealed specific antigen binding and their intensity is proportional to the logarithm of the concentrations of the virus in solution. Under optimal conditions, the immunosensors exhibit a linear response in the 7.6 ng mL?1 to 76 μg mL?1 concentration range of avian influenza virus, and the detection limit is 1.9 ng mL?1. Figure
Label-free immunosensors based on microcantilevers of an atomic force microscope was fabricated by covalently immobilizing monoclonal antibodies to avian influenza virus onto the microcantilever. The performance and factors influencing the performance of the resulting immunosensors were investigated in detail by measuring the cantilever deflections using the optical reflection technique. 相似文献
56.
采用拟协调元方法推导了等腰梯形薄壳元的显式几何刚度阵,用于组合结构屈曲分析的计算,结果表明,这种单元的几何刚度阵收敛快、精度好。 相似文献
57.
一种结构参数识别的两阶段方法 总被引:15,自引:1,他引:15
针对测量信息不完备的剪切型结构 ,建立了一种两阶段系统识别的复合反演方法 ,这种方法包括两部分 :子结构地震动反演和结构参数识别。首先 ,选取可观测的子结构 ,利用一维地震动作用于结构的力学特性 ,将子结构动力方程的有限元列式进行变换 ,得到适合于最小二乘法的简单形式 ,解决了测量信息不完备及结构参数未知条件下的地震动反演问题。其次 ,根据子结构反演得到的地震动输入 ,采用结构参数时域识别技术中的加权整体迭代 -广义卡尔曼滤波器方法 ,成功地识别出了有限测量条件下单元水平结构参数 相似文献
58.
针对精化8-20节点块体元构造了几种不同类型的质量阵,通过对几种支撑条件下的梁进行的振动特性分析,对其进行了比较研究,提出了构造精化8-20节点块体元质量阵的新途径—综合一致质量阵法。结果表明,这种综合一致质量阵方法是几种质量阵形成方法中对提高动力分析精度最为有效的方法。 相似文献
59.
Jianyun Lu Marcia I. Dawson Qiong Ying Hu Zebin Xia Jesse D. Dambacher Mao Ye Xiao‐Kun Zhang Ellen Li 《Magnetic resonance in chemistry : MRC》2009,47(12):1071-1080
The effect of retinoid X receptor (RXR) antagonists on the conformational exchange of the RXR ligand‐binding domain (LBD) remains poorly characterized. To address this question, we used nuclear magnetic resonance spectroscopy to compare the chemical shift perturbations induced by RXR antagonists and agonists on the RXRα LBD when partnered with itself as a homodimer and as the heterodimeric partner with the peroxisome proliferator‐activated receptor γ (PPARγ) LBD. Chemical shift mapping on the crystal structure showed that agonist binding abolished a line‐broadening effect caused by a conformational exchange on backbone amide signals for residues in helix H3 and other regions of either the homo‐ or hetero‐dimer, whereas binding of antagonists with similar binding affinities failed to do so. A lineshape analysis of a glucocorticoid receptor‐interacting protein 1 NR box 2 coactivator peptide showed that the antagonists enhanced peptide binding to the RXRα LBD homodimer, but to a lesser extent than that enhanced by the agonists. This was further supported by a lineshape analysis of the RXR C‐terminal residue, threonine 462 (T462) in the homodimer but not in the heterodimer. Contrary to the agonists, the antagonists failed to abolish a line‐broadening effect caused by a conformational exchange on the T462 signal corresponding to the RXRα LBD–antagonist–peptide ternary complex. These results suggest that the antagonists lack the ability of the agonists to shift the equilibrium of multiple RXRα LBD conformations in favor of a compact state, and that a PPARγ LBD‐agonist complex can prevent the antagonist from enhancing the RXRα LBD‐coactivator binding interaction. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
60.
Doping polyaniline with COO(-)-modified gold nanoparticles by forming stable layer-by-layer multilayer films can shift its electroactivity to neutral pH. The films can electrocatalyze the oxidation of NADH and offer potential applications in other fields, e.g., optoelectronics or biosensing. 相似文献