基于LabVIEW的高温超导材料特性测试实验

高温超导体临界特性的测量是近代物理实验中最为经典的实验之一,本文通过使用GM制冷机,利用Lab-VIEW虚拟仪器软件和高性能采集卡,改进了传统的测量高温超导材料临界特性的实验装置.本测试系统不仅可以测量高温超导体在不同温度下的临界电流,还可以测量其失超传播特性.该实验对于学生了解超导体特性和培养严谨的科学作风十分有益.     

聚丙烯孔洞铁电驻极体膜的电极化及其电荷动态特性

根据栅控恒压电晕充电组合反极性电晕补偿充电法的实验结果计算出铁电驻极体的极化强度.结果说明，伴随着薄膜内孔洞气体的Paschen击穿，该铁电体的极化强度随栅压增加而显著上升.利用上述充电方法和热刺激放电(TSD)谱的分析讨论了这类空间电荷型宏观电偶极子，及与其补偿的空间电荷热退极化的电荷动态特性；阐明了这两类俘获电荷的能阱分布，即构成宏观电偶极子的位于孔洞上下介质层内的等值异号空间电荷分别被俘获在深、浅两种能值陷阱内，而位于薄膜表面层的注入空间电荷则被俘获在中等能值陷阱中. 关键词： 反极性电晕补偿充电法 铁电驻极体 充电电流 热刺激放电     

饮酒驾车模型

据统计,我国每天困饮酒过量而产生的车祸竟达交通事故伤亡总人数的50%-60%,酒后驾车的问题已经引起了社会各界的高度重视.为此本文建立了酒后血液中酒精含量的房室数学模型,从而为司机饮酒驾车提供合理的忠告和建议.     

鞅方法在一类破产问题中的应用

本文从鞅条件出发 ,推导出了总理赔过程分别为复合 Poisson过程与复合二项过程 ,利率强度波动为带跳的 Poisson过程情形下的调节方程 ,并由此得到了一些有趣的结果。     

Crystallographic report: catena‐Aqua(2,2′‐bipyrimidine)lithium(I) perchlorate

A lithium(I) coordination polymer has been formed from LiClO₄ and the 2,2′‐bipyrimidine (bpym) ligand in which each square pyramidal lithium(I) atom is coordinated in the basal plane by four nitrogen donor atoms derived from two bpym ligands and one water molecule at the apical position. These are connected into a layer structure via hydrogen‐bonding interactions involving the perchlorate anions. Copyright © 2004 John Wiley & Sons, Ltd.     

A generalized quasi-sum relations for oscillator strengths in transition arrays: theoretical study of the opacity of Ge plasmas

We present a simplified relativistic configuration interaction method (SRCI), by which all the energy levels and oscillator strengths in each transition array can be calculated. There exist generalized quasi-sum relations for the calculated oscillator strengths in the relevant transition arrays by the SRCI and by an unresolved transition array model (UTA). Based on UTA and the detailed configuration accounting (DCA), with a fully relativistic treatment incorporated with the quantum defect theory, the X-ray absorption spectra for any middle- and high-Z plasmas or composite plasmas can be calculated with much less computational efforts. The gross features of calculated spectra by DCA-UTA are in agreement with the relevant experimental measurements, except some detailed structures in some narrow spectral ranges. Such detailed structures can be calculated by SRCI incorporated with DCA-UTA. As an illustrative example, the absorption spectra of Ge plasmas are calculated by DCA-UTA-SRCI and are in agreement with the experimental opacity data. Therefore, the theoretical method (DCA-UTA-SRCI) verified by experimental measurements will not only be a basic tool to provide “precision” opacity data for the inertial confinement fusion research (ICF) and studies in stellar physics but also can be used to analyze the relevant diagnostic measurements for ICF plasmas.     

Study on the Reaction of Benzimidazolium Salt with Amine Compounds

The addition-hydrolysis reaction of benzimidazolium salt with some mono- and bifunctional amine nucleophiles is reported,and a novel method of biomimetic synthesis for formamides and heterocycle compounds is provided.     

免疫算法在车辆调度问题中的应用

免疫算法是模仿生物体高度进化、复杂的免疫系统仿生的一种智能化启发式算法。本文根据车辆调度问题的具体情况，应用免疫算法解决车辆调度中路线安排问题，并提出了一种基于分组匹配的亲和力的计算方法。实验结果表明，免疫算法能有效地应用于车辆调度中路线安排问题。     

温度对PSⅡCP4 7/D1/D2/Cytb559复合物荧光光谱特性的影响

采用激励光源为514.5 nm的分幅扫描单光子计数荧光光谱装置对经20℃、42℃和48℃不同温度处理后的反应中心复合物CP47/D₁/D₂/Cyt b559的荧光光谱特性进行了研究.经解析,获得不同温度处理后,CP47/D₁/D₂/Cyt b559复合物最大峰值未发生变化,均在682 nm,说明Chla670的能量都由Chla682接收,但损耗愈来愈小,在48℃时,损耗程度最小,而其荧光百分比未发生多大变化.振动副带～700 nm和～740 nm的中心波长都发生蓝移,在不同温度下分别为:20℃ 703 nm,749 nm;42℃ 697 nm,744 nm;48℃ 694 nm,740 nm.因此可以推测温度的升高,影响了CP47/D₁/D₂/Cyt b559色素蛋白的二级结构以及色素分子的空间位置,使最大峰值处的荧光强度逐渐降低,振动副带逐渐蓝移.42℃的温度已造成影响,48℃影响较大.