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61.
The sol-gel derived glucose biosensor was developed, and the sol-gel membrane was organically modified by N-(3-triethoxysilylpropyl)-ferrocenylmethylamine (FcSi) as sol-gel precursor to make electrochemical biosensor. The structure of biosensor was sol-gel/FcSi+GOx/GC type (glucose oxidase, GOx). The ferrocene mediator was chemically immobilized to the silane network, and GOx was entrapped to the sol-gel glass network. Therefore, these structures prevented mediator leakage and retained the enzyme activity. Additionally, pH of electrolyte, temperature effects, and interference of positive substances with biosensor were investigated. And the electrochemical performance of biosensor was studied by amperometry. The results indicated that the linear range, detection limit. and response slope of biosensor was 2.00×10^-4-1.57×10^-3 mol·L^-1, 2.0×10^-4 mol·L^-1 and 5.06×10^5 nA·mol^- 1·L, respectively. 相似文献
62.
The anomalous electron thermal transport model baaed on collisionleas plasma instabilities driven by electron temperature gradient is applied to tokamak plasma with auxiliary heating. The steady state electron equation is solved and the results ahow good agreement with experimental observations including the principle of profile consltency, various scaling laws, and even some results for detached plasmas. 相似文献
63.
The self-dual Yang-Mills field theories in two-dimensional representations are formulated. The Biicklund transformation and the conservation law are given in the framework of the prolongation theory. Furthermore, we derive the conserved current algebras which are in essence the Yang-Baxter relations. 相似文献
64.
For the preparation of high-active and high-isospecific catalysts for propylenepolymerization,various supports such as Mg-alkyls[1 ] ,Mg( OH) 2 [2 ] ,Mg O[3] ,Mg Cl2 [4] .Grignard compounds[5] ,or magnesium alkoxide[6] had been used.Lately,Mg( OEt) 2 -supported Ti Cl4catalysts including an organic chloride and/ or an internal donor preparedby physical milling method and chemical reaction method were studied and it was foundthat Mg( OEt) 2 is converted to Mg Cl2 by reaction with Ti Cl4a… 相似文献
65.
讨论了应用高频电感耦合等离子体(ICP)消解氟里昂类废弃物的可行性及与国际先进技术的比较;应用低功率ICP系统进行氟里昂12的模拟消解,用GC-ECD方法对尾气中的残余成分和浓度进行分析,证明该系统对氟里昂12的处理效率高于99.9%,可以发展成为未来环保废物处理领域的一项新技术。 相似文献
66.
The geometry and vibrational frequencies of the F-·H2O system are determined by ab initio calculations (SCF and CISD levels of theory). 相似文献
67.
68.
微波合成PtRu/C纳米催化剂及其对甲醇电化学氧化性能 总被引:4,自引:0,他引:4
PtRu/carbon nanosized catalyst with PtRu loading of 26.4wt% (Rt∶Ru=1.0∶1.0~1.1) was rapidly synthesized by the microwave polyol process employing the ethylene glycol solution of H2PtCl6 and RuCl3 as precursors in the presence of XC-72 carbon support. TEM observations demonstrated that microwave-prepared PtRu nanoparticles were narrowly distributed and highly dispersed on the carbon with an average size of 3.9 nm. Electrochemical experiments showed that microwave-synthesized PtRu/carbon catalyst exhibited very high catalytic activity for electro-oxidation of liquid methanol at room temperature. 相似文献
69.
Pulsatile flows in the vicinity of mechanical ring-type constrictions in pipes were studied for transitional turbulent flow with a Reynolds number (Re) of the order of 104. The Womersley number (Nw) is in the range 30–50, with a corresponding Strouhal number (St) range of 0·0143–0·0398. The pulsatile flows considered are a pure sinusoidal flow, a physiological flow and an experimental pulsatile flow profile for mechanical aortic valve flow simulations. Transitional laminar and turbulent flow characteristics in an alternating manner within the pulsatile flow fields were studied numerically. It was observed that fluid accelerations tend to suppress the development of flow disturbances. All the instantaneous maximum values of turbulent kinetic energy, turbulent viscosity and turbulent shear stress are smaller during the acceleration phase than during the deceleration period. Various parametric equations have been formulated through numerical experimentation to better describe the relationships between the instantaneous flow rate (Q), the pressure loss (ΔP), the maximum velocity (Vmax), the maximum vorticity (ζmax), the maximum wall vorticity (ζw,max), the maximum shear stress (τmax) and the maximum wall shear stress (τw,max) for turbulent pulsatile flow in the vicinity of constrictions in the vascular tube. An elliptic relationship has been found to exist between the instantaneous flow rate and the instantaneous pressure gradient. Other linear and quadratic relations between various flow parameters were also obtained. 相似文献
70.
This paper presents laminar and turbulent mixed convection solutions of a driven cavity flow using the finite element method. For the laminar flow, distributions of velocity and temperature with and without the effect of buoyancy force are presented and compared. For the turbulent flow, governing partial differential equations of the thermal turbulence two-equati on model and kinetic turbulence two-equation model are used. Corresponding results such as kinetic eddy diffusivity, kinetic eddy energy, thermal eddy energy and their dissipations are presented. 相似文献