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31.
Detection of sulphamethazine with an optical biosensor and anti-idiotypic antibodies 总被引:3,自引:0,他引:3
We describe the development of an assay for the detection of sulphamethazine in animal urine with a surface plasmon resonance (SPR) biosensor. In order to obtain a general assay that can easily be transferred to other veterinary drug residues, a monoclonal antibody against sulphamethazine and a corresponding anti-idiotypic antibody were used. The assay had a lower detection limit of 5 μg/l which is well below the maximum residue limits (MRL) of 100 μg/l and can be used for screening purposes in animal urine. The binding reaction between the antibodies as occurring during sensor application was characterized with respect to avidity and kinetic properties. 相似文献
32.
33.
In this paper, we report some comparative simulations between lattice BGK and lattice Bolzmann schemes for two-dimensional fluid flows. A quantitative assessment of the validity of the lattice BGK and lattice Bolzmann schemes is presented for the two-dimensional weakly compressibleKolmogorov flow. We use this flow to study the difference of the two schemes at small scales. A lowReynolds (R
e 300) number simulation shows the almost identical energy spectra for both schemes except for the small-scale dynamics of lattice Bolzmann which is more noisy. Because of the intrinsic difficulties of nonlinear stability analysis, we use numerical simulations to investigate which scheme is more stable. It turns out the lattice BGK is more stable. It turns out the lattice BGK is more robust than lattice Bolzmann by increasing theReynolds numbers. Detailed comparison with other methods (e.g., spectral method) remains to be done in the near future. 相似文献
34.
以3种不同VGO为原料,在200 mL固定床连续等温加氢试验装置上,考察了反应温度、氢分压、体积空速、氢油体积比等工艺条件对加氢精制催化剂A脱硫反应的影响,同时建立了相应的关联曲线,探讨工艺条件对精制油中硫含量的影响趋势。建立了减压蜡油加氢脱硫宏观动力学模型,对动力学模型进行优化计算和实验验证,结果表明模型具有一定的预测精度。 相似文献
35.
造纸与化工混合污水处理生化动力学研究 总被引:1,自引:0,他引:1
采用造纸厂中段污水、化肥厂含氨氮污水、化工厂含酚污水、农药厂有机磷污水按不同比例混合,研究在微生物作用下生物降解过程,揭示其生化动力学规律。研究结果表明,混合污水生化动力学系数为衰减系数K_d=0.035d~(-1),产率系数Y=0.864mg(VSS)/mg(BOD_5),底物最大比降解速率为q_(max)=0.201mg(BOD_5)/mg(VSS)d,半速率系数为K_s=48.9mg(BOD_5)/L。实验结果所得的生化动力学系数,为区域性污水集中处理提供理论参考依据。 相似文献
36.
In this study, the growth kinetics of titanium nitride layer deposited on pre-nitrided AISI 1020 steel samples by thermo-reactive diffusion (TRD) techniques in a solid medium was reported. Steel was at first tufftrided and then titanium nitride coating treatment was performed in a powder mixture consisting of ferro-titanium, ammonium chloride and alumina at 1173, 1223 and 1273 K for 1-4 h. Titanium nitride layer thickness on the titanium nitride coated AISI 1020 steel ranged from 5.5 to 19.2 μm depending on treatment time and temperature. Layer growth kinetics was analyzed by measuring the depth of titanium nitride layer as a function of time and temperature. The kinetics equation of the reaction has also been determined with Arhenius equation K=Koexp(−Q/(RT). The result showed that the diffusion coefficient (K) of the process increased with treatment temperature. Activation energy (Q) for TRD process was calculated as 187.09 kJ/mol. The diffusion coefficients (K) changed between 6.637×10−11 and 2.097×10−10 cm2/s depending on the process temperature. 相似文献
37.
两种镍基合金涂层抗高温氧化性能研究 总被引:5,自引:0,他引:5
对自行研制的新型高铬镍基合金 (w(Cr) >40 % )涂层和传统的镍铬合金 (Ni70Cr30 )涂层在 6 5 0℃和80 0℃下的高温氧化动力学规律进行了研究。采用配有能谱分析仪的扫描电镜以及X射线衍射仪等对氧化产物的形貌和相组成等进行了分析。两种镍基合金涂层均表现出较好的抗高温氧化性能 ,尤其是由新型高铬合金制备的涂层 ,其表面生成了连续的Cr2 O3 保护膜 ,具有更低的氧化速度 相似文献
38.
Although the Eulerian approach coupling the kinetic theory of granular flow is usually used to study granular flows with relative lower solid fractions, it can be used to study relative denser granular flows if appropriate solid phase kinetic viscosity values were adopted. A granular bed surface fitting (BSF) method is proposed to determine the appropriate solid phase kinetic viscosities of the granular flows in a rotating drum. The specularity coefficient is also used to address the interaction between particles and the drum wall. The BSF solid phase kinetic viscosity increases with decreasing of particle sizes and drum rotational speeds. The BSF solid phase kinetic viscosity and the specularity coefficient follow a power-law relationship with 0.6–1.1 as the exponent of the specularity coefficient. The BSF solid phase kinetic viscosities for the particles of two different sizes are used to study particle segregation in a rotating drum. The core thickening segregation mechanism and the segregation band formations are well predicted. 相似文献
39.
Wei Cai Vasily V. Bulatov Jo o F. Justo Ali S. Argon Sidney Yip 《Computational Materials Science》2002,23(1-4):124-130
We describe a kinetic Monte Carlo (kMC) approach to modeling dislocation motion, directly linking the energetics of dislocation kink nucleation and migration on the atomistic scale with the experimental data on the microscale. A study of planar glide of screw dislocation in Si, an ideal test-bed for our method is first discussed, followed by preliminary results for a more complicated problem, three-dimensional motion of screw dislocation in BCC metals. We find that accuracy of the model predictions, even in the favorable case of Si, cannot claim to be quantitative because of uncertainties in the atomistic results for kink energetics. On the other hand, the kMC method is useful for qualitatively probing the mechanisms controlling dislocation motion, and it is capable of providing plausible explanation of some puzzling features of the experimental data. 相似文献
40.
导弹水下动机座垂直发射载荷建模与仿真 总被引:1,自引:0,他引:1
导弹在水下动机座垂直发射过程中,受到横向流与弹性减震环对弹体的耦合作用,造成弹体出筒过程的受力状态的复合特征,对弹体出筒安全有很大影响。为解决上述问题,基于流体力学和动力学理论,针对潜艇带速水下垂直发射导弹过程中导弹的运动特征、流体动力特性、弹体与弹性减震环的相互作用进行研究,建立了水下动机座垂直发射导弹的横向载荷计算模型和耦合算法,并给出了载荷仿真算例。结果表明:所建立的模型与计算方法可行,可为导弹结构设计和发射系统参数设计提供研究参考和依据。 相似文献