Numerical simulation for the simple shear test in amorphous glassy polymers

In this paper, a driving stress finite element method of elastic-plastic large deformation based on implicit time integrating algorithm and an eight-chain molecular network model is used for the numerical simulation of the simple shear test of polycarbonate (PC) materials. The simulated results are compared with experimental ones. The strain localization propagation for the shear band deformation for simple shear deformation is investigated numerically. The effects of microstructure parameters in the model on strain softening and orientation hardening of the PC are discussed in detail. Supported by the National Natural Science Foundation of China.     

沉桩对周围环境的影响及防护措施

结合工程具体实例，介绍沉桩对周围环境的影响及防护措施并进行了效果分析。     

The Thermodynamic Driving Force in the Kinetic Evaluation of Thermoanalytical Curves

This paper outlines the different ways of taking the distance from thermodynamic equilibrium into account in kinetic studies based on thermoanalytical experiments. The three main approaches are: (i) avoiding or neglecting the effect of the reverse reaction, (ii) describing the influence of distance from equilibrium on apparent kinetic parameters, and (iii) incorporating a driving force factor in the rate equation. Finally, the contradiction of the microscopic nature of the processes and the macroscopic character of the usual rate equation are briefly discussed. This revised version was published online in August 2006 with corrections to the Cover Date.     

Sharp thresholds of two-components attractive Bose-Einstein condensates with an external driving field

In this Letter, we establish a sharp condition of global existence for the solution of two-components attractive Bose-Einstein Condensates with an external driving field. And this condition is related to the ground state solution of some steady-state two-coupled nonlinear Schrödinger equations.     

JOB-9003和JB-9014炸药平面爆轰驱动飞片的对比研究

采用双灵敏度激光速度干涉仪(VISAR)测量了JOB-9003和JB-9014两种炸药平面一维爆轰驱动飞片的速度历史,比较了二者的做功能力;并用DYNA2D程序进行了数值模拟。在有JO-9159炸药的条件下,实验和计算结果表明,JB-9014炸药的做功能力可以达到JOB-9003炸药的75.0%;无JO-9159炸药条件下的计算结果表明,JB-9014炸药的做功能力约为JOB-9003炸药的71.2%     

A NEW MODIFIED LINEAR DRIVING FORCE(MLDF)MODEL

IINTRODUCTIONAdiffusionphenomenonexistSinavarietyofadsorptionprocesses,andplaysanimportalroleintheadsorptionrate.ThediffusionofadsorbateinporousmediumisanunsteadymasstTansferprocess,whichcanbedescribedbypartialdifferentialequation.Howevef,theanalysissolutionofthediffusionrateequationisaninfiniteseries,soithasnotbeenwidelyusedintheadsorptionprocesses.Inordertosimplifytheadsorptionratemodel,alotofapproximationshavebeenputforward,ofwhichthelineardrivingforce(LDF)modelproposedbyGlueckauf(1…     

The pump-probe approach to coherent backscattering of intense laser light from cold atoms

We present a new approach to near-resonant coherent backscattering of light from cold two-level atoms. In the dilute regime, where the distance between atoms is much larger than the laser wavelength, this approach is able to account for multi-photon scattering processes between many atoms through solutions of single-atom optical Bloch equations. We elaborate the method for double scattering from two atoms, and discuss the way of its extension for dilute, cold atomic clouds.     

Charge-transfer Interaction: A Driving Force for Cyclodextrin Inclusion Complexation

PM3 calculations were performed on the complexation of -cyclodextrin (-CD) with nitrobenzene, benzoic acid, benzoate anion, 4-nitrophenol, and 4-nitrophenolate anion. The results, in agreement with the experimental observations, indicated that the complex -CD-benzoic acid was more stable than -CD-nitrobenzene, and -CD-4-nitrophenolate was more stable than -CD-4-nitrophenol. Frontier orbital analysis suggested that charge-transfer interaction led to such behaviors, and hence constituted a nontrivial driving force in the molecular recognition of -CD.     

Tagging of Model Amphetamines with Sodium 1,2‐Naphthoquinone‐4‐sulfonate: Application to the Indirect Electrochemical Detection of Amphetamines in Oral (Saliva) Fluid

Proof‐of‐concept is shown for the indirect electrochemical detection of model amphetamines, D ‐amphetamine sulfate and pseudoephedrine, based on the labeling of the amphetamine models with sodium 1,2‐naphthoquinone‐4‐sulfonate (NQS). The presence of the amphetamine models is monitored via either the reduction in the magnitude of the voltammetric peak corresponding to the electrochemical reduction of the quinone functionality of the sodium 1,2‐naphthoquinone‐4‐sulfonate or via growth of a new voltammetric peak related to reaction between the amphetamine model and NQS, both of which are well resolved from one another. The protocol is shown to be successful in artificial saliva and authentic human oral (saliva) fluid. Such a protocol may be particularly attractive for roadside testing of amphetamines in drug drivers.     

聚偏氟乙烯微孔滤膜-聚多巴胺-氧化石墨烯固相萃取结合离子迁移谱快速检测尿液中的麻黄碱

建立了新型聚偏氟乙烯微孔滤膜-聚多巴胺-氧化石墨烯固相萃取结合便携式高分辨离子迁移谱对尿液中的麻黄碱进行快速检测的方法。通过对新型固相萃取膜的制备过程、吸附、洗脱过程进行优化,可对尿液中麻黄碱实现5 min吸附、10 min洗脱、30 ms进样的快速检测。结果显示,麻黄碱在0.124～6.129μg/mL质量浓度范围内的线性良好,检出限为9.60 ng/mL,方法的回收率为91.0%～113%。该方法能够快速地完成对尿液中麻黄碱的检测,为药驾在线检测和现场监察提供了有效手段。