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21.
Qing Shi Dong Yang Yanlei Su Jian Li Zhongyi Jiang Yanjun Jiang Weikang Yuan 《Journal of nanoparticle research》2007,9(6):1205-1210
Lipase from Candida rugosa was covalently anchored onto acid-treated multi-walled carbon nanotubes (MWNTs) through a self-catalytic mechanism. A variety
of characterization techniques including FTIR, Raman spectroscopy, and XPS were employed to demonstrate the formation of the
ester linkage between lipase and MWNTs. The MWNTs-lipase biocomposites showed significantly increased solubility in some common-used
organic solvents, such as THF, DMF and chloroform. This study may offer a novel and facile route for covalent modification
of carbon nanotubes, and expand the potential utilization of both lipases and MWNTs in the fields of biocatalyst and biosensor. 相似文献
22.
An equation to express ion exchange selectivity coefficient was derived and used for calculating that of PPY film with the results obtained by cyclic voltammetric measurement. PPY film was synthesized by electrochemical method in aqueous solution using K4Fe(CN)6 as supporting electrolyte, and the anions were doped into the film. Ion exchange behaviour of doped Fe (CN)63-/4- in the PPY film with Cl?, NO3? or F? ions in solution has been studied, and the corresponding ion exchange selectivity coefficients were determined. 相似文献
23.
Dong Hwan Choi Yoshio Katakura Rieko Matsuda Yuzuru Hayashi Masato Hirobe Yasuhiro Goda Kazuaki Ninomiya Suteaki Shioya 《Analytical sciences》2007,23(2):215-218
The mathematical model for predicting the precision, limit of detection (LOD) and range of quantitation (ROQ) in a competitive enzyme-linked immunosorbent assay (ELISA) proposed by Hayashi et al. (Anal. Chem., 2004, 76, 1295) was validated. The model describes the relative standard deviation (RSD) of concentration estimates by the RSDs of pipetting volumes of analyte, enzyme-conjugated antigen, antibody and substrate solutions, and the standard deviation (SD) of inherent absorbances between the wells in an ELISA plate. For 6 kinds of direct competitive ELISA kits, the LOD and ROQ predicted by the model agreed well with those obtained by experiments with real samples. It was also confirmed that the model is applicable to the prediction of uncertainty that depends on the pipetting error of the viscous antiserum solution. The model was demonstrated to be useful for estimating the LOD and ROQ of competitive ELISA. 相似文献
24.
Xun Dong 《Discrete and Computational Geometry》2006,35(3):457-471
We prove that the bounded complex of an affine oriented matroid is
pure and collapsible. We also generalize Zaslavsky's central
decomposition theorem for hyperplane arrangements to affine
oriented matroids. 相似文献
25.
In this note, the authors resolve an evolutionary Wente's problem associated to heat equation, where the special integrability of det▽u for u ∈ H1(R2,R2) is used. 相似文献
26.
用变加速动力学的急动度(加加速度)概念,分析了车辆、电梯的乘座舒适性与高层钢结构建筑的风振舒适性问题. 相似文献
27.
HarmonicAnalysisontheCompactHomogeneousSpaces──aboutFourierMultiplierofH~P(M)Space¥DongDaozhen;ZhengXuean(HenanUniversity,Kai?.. 相似文献
28.
对文献[1]中提出的两质点两滑轮组成的两自由度问题,现采用简化物理模型,用牛顿力学方法分析绳中张力随右边B球摆角θ的变化,进而列出左边A球所受合外力随θ角变化的表达式,作出图像,可较为合理地解释其实验现象。 相似文献
29.
In this paper we define the vertex-cover polynomial Ψ(G,τ) for a graph G. The coefficient of τr in this polynomial is the number of vertex covers V′ of G with |V′|=r. We develop a method to calculate Ψ(G,τ). Motivated by a problem in biological systematics, we also consider the mappings f from {1, 2,…,m} into the vertex set V(G) of a graph G, subject to f−1(x)f−1(y)≠ for every edge xy in G. Let F(G,m) be the number of such mappings f. We show that F(G,m) can be determined from Ψ(G,τ). 相似文献
30.
用三维样边界元法分析水闸闸室结构。底板,闸墩和载水墙等为其子结构,交通桥,工作桥和胸墙等处理为内部支撑。地基和边载可以是任意的,只要能给定地表位移面力关系。在各种工况下,不论是设置平板门还是弧形门,是平底板是反拱底板,即使在稀疏剖分下也能给出高精度的位移场,应力场和地基反力场。 相似文献