Propagation of a few-cycle laser pulse in a V-type three-level system

Propagation of a few-cycle laser pulse in a V-type three-level system (fine structure levels of rubidium) is investigated numerically. The full three-level Maxwell-Bloch equations without the rotating wave approximation and the standing slowly varying envelope approximation are solved by using a finite-difference time-domain method. It is shown that, when the usual unequal oscillator strengths are considered, self-induced transparency cannot be recovered and higher spectral components can be produced even for small-area pulses.     

Effect of vacuum-induced coherence on lasing without inversion in an equispaced three-level ladder system

The effects of vacuum-induced coherence (VIC) on the properties of the absorption and gain of the probe field in an equispaced three-level ladder atomic system are investigated. It is found that lasing without inversion (LWI) is remarkably enhanced due to the effect of VIC in the case of the small incoherent pump rate.     

二溴羟基苯基荧光酮荧光熄灭法测定微量钼

本文用荧光熄灭法研究了十溴羟基苯基荧光酮(DBH-PF)-溴化十六烷基三甲铵(CTMAB)-Mo(Ⅵ)体系的测定方法及条件。在0.002～0.008mol/L的H_3PO_4介质中,在CTMAB存在下,钼(Ⅵ)与试剂形成1:2的桔红色络合物,其最大激发波长为470nm和502nm,最大发射波长为520nm。钼在0.03～0.50μg/25ml范围内具有线性关系,检出限为0.03μg/25ml。本法灵敏度高,选择性好,用于检测合金钢中的微量钼,结果满意。     

智能化车辆光度测试系统的研制

本文介绍了一种自动测试汽车车灯配光性能仪器的设计原理、结构框图和精度分析。仪器采用微机控制、自动完成定位、数据采集、标准判别和表格打印。经实际使用表明：仪器具有较高精度，其转动定位精度达到０．０１°，照度测试精度不大于２％，完全满足国标对车灯性能测定的要求     

用正交光路全息干涉CT技术重建电弧等离子体三维温度场

本文利用正交光路全息干涉技术和计算机有限角层析算法,借助电弧等离子体物理方程,对非对称电弧等离子体三维温度场的诊断进行了研究.     

弹簧的弹力能突变吗?

弹簧的弹力是由于弹簧的形变产生的，要它恢复形变或产生形变就需要时间，于是有的学生认为在剪断弹簧的一瞬间，弹力不能够突变．这种说法对吗？请看下面的例题．     

荧光素单磷酸酯的合成和其应用于荧光光度法测定酸性磷酸酯酶

本文新合成了荧光素单磷酸酯,通过元素分析、红外、热谱确定了其结构,探讨了其生成机理,并将其应用到酸性磷酸酯的荧光分析,深入研究了它与酸性磷酸酯酶之间反应的条件、检测此酶的线性范围、检测限和米氏常效.     

胆绿素还原酶电极及电位法测定胆红素的研究

本文研制了胆绿素还原酶电极,采用电位法测定胆红素。胆绿素还原酶以牛血清白蛋白和戊二醛固定化制成酶膜,覆盖在石墨电极上在辅酶Ⅰ存在下进行测定,铁氰离子作为电子传递介质。胆红素在空气存在下氧化为胆绿素,再以胆绿素还原酶电极进行检测。线性响应范围为1×10~(-6)-1×10~(-4)mol/L胆绿素(胆红素),酶膜寿命约60h。本法可在水溶液中测定胆红素。     

区间判断的凸锥模型与排序方法

本文用凸锥模型对层次分析法中区间判断条件下的排序问题进行研究，给出了权重向量的合理算法．并对区间判断下权重向量的合理位置，产生逆序的可能性等重要问题进行了探讨和研究，给出了计算实例．     

Study on the Interaction between CdSe Quantum Dots and Bovine Serum Albumin with Ultraviolet Visible Absorption Spectroscopy

QDs (also called semiconductor nanocrystallines) were attracted considerable attention in the past decade1, 2. They have been used as luminescent probes in biology, medicine and more recently in analytical chemistry3-5. The interaction between QDs and ino…