地方高校省级物理示范实验室建设的探索与实践

提出了示范实验室建设的思路与目标,阐述分层次模块化的实验教学体系,介绍了多样化的实验教学手段。经过3年的探索与实践,示范实验室建设成效显著、特色明显,取得了较为显著的成绩,有一定示范性和辐射作用。     

纳秒脉冲下聚合物电树枝引发实验方法

 借鉴直流、交流的研究经验,比较了纳秒脉冲条件下几种不同的电树枝老化实验方法。对单针-板电极和多针-板电极在纳秒脉冲下实验结果的一致性进行考察,结果表明,多针-板电极系统可以在提高实验效率的同时保证结果的准确性。采用步进法和累加法进行了不同频率下聚苯乙烯电树枝引发实验,结果表明:两种方法得到的纳秒脉冲下聚苯乙烯电树枝引发电压-频率特性基本一致,在50~500 Hz范围内,引发电压随频率的升高而降低;在500~800 Hz范围内,引发电压随频率的升高而增加。最后讨论了对于不同脉冲功率装置中绝缘材料老化试验设计的方法。     

透射光栅的实验标定和衍射效率的理论模拟

透射光栅广泛应用于软X射线能谱测量.为了获得用于惯性约束聚变研究的透射光栅的各级衍射效率及其他参数,在北京同步辐射源上200—1600 eV能量范围内对其进行了标定,获得了透射光栅衍射效率的实验结果.扩展了透射光栅衍射效率的计算方法,提出了7边准梯形截面衍射效率计算模型.分析拟合了实验数据,理论结果与实验结果很好符合.得到了7边准梯形的透射光栅栅线截面结构. 关键词： 透射光栅 衍射效率 实验标定 光栅模型     

微尺度水平单管内流动沸腾特性实验研究

对非共沸混合工质R134a/R32(75/25)在水平微尺度管道内的流动沸腾换热实验结果进行了分析和讨论,以探究微细通道内流动沸腾换热的主导机制。对影响其换热的多种因素(热流密度、质量流量和质量干度)进行了分析,实验得出,当质量干度较低时,热流密度和质量流量共同控制着微尺度管内的换热方式,当热流密度的影响占主导地位时,管道内的换热以核态沸腾为主;当质量流量的影响占主导地位时,管道内的换热以强制对流为主。     

车辆天窗气动噪声的数值分析与实验研究

本文从汽车天窗气动噪声的机理入手,利用与实车几何尺寸为1:5的简化模型进行了空腔绕流的数值计算,分析了其流场结构及气动噪声产生的原因.在低速静音风洞中进行了不同流速下的流场和声场实验研究,研究了天窗不同位置的速度剪切层变化,以及不同流速下的声压级变化,发现了除了特征频率下的风振噪声,还存在较大频率范围的气动噪声,其随着...     

Procedurally Rational Volunteers

The mixed-strategy equilibrium applied to the volunteer's dilemma (Diekmann, 1985 Diekmann , A. ( 1985 ). Volunteer's dilemma . Journal of Conflict Resolution , 29 , 605 – 610 .[Crossref], [Web of Science ®] , [Google Scholar]) predicts that the probability that at least 1 bystander volunteers decreases, if the number of bystander increases. I argue that this prediction lacks empirical support and demonstrate that an alternative solution concept from the literature on bounded rationality, the procedurally rational equilibrium (Osborne &; Rubinstein, 1998 Osborne , M. J. &; Rubinstein , A. ( 1998 ). Games with procedurally rational players . American Economic Review , 88 , 834 – 847 .[Web of Science ®] , [Google Scholar]), yields alternative predictions. I supply some empirical evidence that the alternative solution concept fares better in explaining observed behavior in the volunteer's dilemma.     

Degradation Thermique des Polystyrenes et du Polychlorure de Vinyle : Application d'une Matrice d'experiences a l'etude de l'influence des Parametres de l'analyse Thermomanometrique. Partie I : Exploitation des résultats par traitement mathématique

Thermal degradation of polystyrene and polyvinylchloride was studied by thermomanometric analysis. A design of experiments was used to quantify the influence of 8 physico-chemical parameters on the responses of the analyser and on the different types of degradation compounds. This revised version was published online in July 2006 with corrections to the Cover Date.     

非视线紫外光大气传输模型的建立及验证

基于蒙特卡罗方法建立了非视线紫外光传输模型。利用此模型模拟了不同传输距离、不同发射和接收仰角等多种传输条件下的传输情况,并在同等条件下进行了相关实验。结果表明,在相同条件下,信号强度模拟曲线与实验曲线的变化趋势相同且吻合较好,但具有一定的误差。进一步分析指出,模型中大气散射系数、吸收系数、分子散射比、传输测试距离等参数的误差影响了模拟结果的准确,以及模拟与实验曲线的吻合程度。     

Optimization of Oligosaccharide Synthesis from Cellobiose by Dextransucrase

There is a growing market for oligosaccharides as sweeteners, prebiotics, anticariogenic compounds, and immunostimulating agents in both food and pharmaceutical industries. Interest in novel carbohydrate-based products has grown because of their reduced toxicity and low immune response. Cellobiose is potentially valuable as a nondigestible sugar. The reaction of cellobiose, as an acceptor with a sucrose as a donor, catalyzed by a dextransucrase from Leuconostoc mesenteroides B-512FMCM, produced a series of cellobio-oligosaccharides. This production system was optimized using a Box–Behnken experimental design for 289 mM of sucrose and 250 mM of cellobiose and 54 U of the enzyme at pH 5.2 and 30 °C, to produce maximum yields of oligosaccharide.     

Interference theory: Moment solution for two component adsorption chromatography

Summary Moment analysis is used to study two component perturbation chromatography with linear non-equilibrium adsorption. The interference between components is included through the adsorption equilibrium. In this work, the expressions for the first and second moments of two component pertubations have been obtained for the first time. They are just the vectorization of those for the single component system, and they clearly show the interference between components. These results could be applied to establish an experimental procedure to measure adsorption equilibrium and kinetic data.