石墨炉原子吸收法测定钒的研究

本文比较了在标准石墨管,热解涂层和全热解石墨管中钒的吸收信号形状。用全热解石墨管和EDTA铵盐作基体改进剂,直接测定水系沉积物中痕量钒。方法的特征量为61pg/0.0044A。     

马氏调制费率下复合Poisson风险模型的Lundberg型不等式

对于具有马氏调制费率的复合Poisson风险模型，用无穷小生成元构造鞅的方法，导出了破产概率的Lundberg不等式。     

(Me3Si)2NBCl2和(Me3Si)2NB(Cl)NHSiMe3的合成及其成环反应

自从氮化硼陶瓷纤维用聚合物先驱体法[1]合成以后,硼氮六元环化合物越来越为人们所重视[2],文中在制备氮化硼纤维先驱体的过程中,合成了其中间产物,通过热缩合成环反应,合成了含有硼氮六员环的化合物,并采用色-质联用技术对其进行了表征。1　实验部分参照文献[3],改用液氮和丙酮为冷冻剂,控制温度在-50到-40℃,搅拌下向三氯化硼的正戊烷溶液中缓慢滴加三乙胺的正戊烷溶液,滴完后Ｎ2气氛下-50℃加丙酮冷凝回流2ｈ,慢慢由-50℃升至室温,抽滤即得到白色产物Ｅｔ3ＮＢＣｌ3(Ａ)。将Ａ溶于适量苯中[4,5],加入等物质的量的三乙胺,加热回流搅拌…     

粗糙波面光学传递函数像质评价准则和粗糙度公式理论

建立了包含波面像差和粗糙度影响的粗糙波面光学传递函数及其像质评价准则，讨论了粗糙度公差的理论和标准。     

Lagrangian analysis of the formation and mass transport of compressible vortex rings generated by a shock tube

In order to understand the mass transport and the dynamic genesis associated with a compressible vortex formation,a dynamic analysis of compressible vortex rings (CVRs) generated by shock tubes by using the framework of Lagrangiancoherent structures (LCSs) and finite-time Lyapunov exponents field (FTLE) is performed. Numerical calculation is performed to simulate the evolution of CVRs generated by shock tubes with 70 mm, 100 mm, and 165 mm of the driver sectionat the circumstances of pressure ratio = 3. The formation of CVRs is studied according to FTLE fields. The mass transportduring the formation is obviously seen by the material manifold reveled by FTLE fields. A non-universal formation numberfor the three CVRs is obtained. Then the elliptic LCSs is implemented on three CVRs. Fluid particles separated by ellipticLCSs and ridges of FTLE are traced back to t = 0 to identify the fluid that eventually forms the CVRs. The elliptic LCSsencompass around 60% fluid material of the advected bulk but contain the majority of the circulation of the ring. The otherparts of the ring carrying almost zero circulation advect along with the ring. Combining the ridges of FTLE and the ellipticLCS, the whole CVR can be divided into three distinct dynamic parts: vortex part, entrainment part, and advected part. Inaddition, a criterion based on the vortex part formation is suggested to identify the formation number of CVRs.     

Nano-scale gap filling and mechanism of deposit-etch-deposit process for phase-change material

Ge2Sb2Te5 gap filling is one of the key processes for phase-change random access memory manufacture.Physical vapor deposition is the mainstream method of Ge2Sb2Te5 film deposition due to its advantages of film quality,purity,and accurate composition control.However,the conventional physical vapor deposition process cannot meet the gapfilling requirement with the critical device dimension scaling down to 90 nm or below.In this study,we find that the deposit-etch-deposit process shows better gap-filling capability and scalability than the single-step deposition process,especially at the nano-scale critical dimension.The gap-filling mechanism of the deposit-etch-deposit process was briefly discussed.We also find that re-deposition of phase-change material from via the sidewall to via the bottom by argon ion bombardment during the etch step was a key ingredient for the final good gap filling.We achieve void-free gap filling of phase-change material on the 45-nm via the two-cycle deposit-etch-deposit process.We gain a rather comprehensive insight into the mechanism of deposit-etch-deposit process and propose a potential gap-filling solution for over 45-nm technology nodes for phase-change random access memory.     

灾情巡视问题的蚁群两目标优化算法研究

分析目前灾情巡视问题求解方法存在的缺陷,归纳出灾情巡视问题两目标优化模型.针对灾情巡视问题模型特点,引入蚁群算法和多目标优化理论,提出两个灾情巡视问题的蚁群两目标优化算法:算法1将灾情巡视问题的道路网络转化为完全图,增加m-1个(m为巡视组数)虚拟巡视起点,将灾情巡视两目标优化问题转化为单旅行商两目标优化问题,然后使用蚁群算法和多目标优化理论进行迭代求解.算法2使用一只蚂蚁寻找一个子回路,m个子回路构成一个灾情巡视可行方案,采用罚函数法和多目标优化理论构建增广两目标优化评价函数,使用g组,共g×m只蚂蚁共同协作来发现灾情巡视问题的最优解.算法特点:①算法1将灾情巡视两目标优化问题转化为单旅行商两目标优化问题,可以充分利用已有蚁群算法求解单旅行商问题的研究成果;②两个算法引入蚁群算法,提高了算法效率;③两个算法克服目前灾情巡视问题的求解方法不严密性缺陷;④两目标优化算法可以为用户提供多个满足约束条件的Pareto组合解,扩大了用户选择范围,增强了算法的适用性.算法测试表明:灾情巡视问题的蚁群两目标优化算法是完全可行和有效的.     

高清折反式视频显微镜

为了实现对细胞工厂中细胞的实时监测,设计一款高分辨率、长工作距离的视频显微镜。采用卡塞格林式物镜与折射式显微系统相结合的设计方法,在反射式系统中加入厚弯月形透镜补偿系统产生的像差,缩短光学系统的横向尺寸,校正像差。针对被观察细胞的具体特征,设计了一种工作距离100mm、分辨率1.2μm、线视场2mm的视频显微镜,达到高清水平,系统很好地校正色差、球差、场曲和畸变,达到了平场消色差显微镜的要求。实现对细胞状态的高清实时监测。     

The relation between and violation of Hardy＇s non-locality Bell inequality

We give an analytic quantitative relation between Hardy＇s non-locality and Bell operator. We find that Hardy＇s non-locality is a sufficient condition for the violation of Bell inequality, the upper bound of Hardy＇s non-locality allowed by information causality just corresponds to Tsirelson bound of Bell inequality and the upper bound of Hardy＇s non- locality allowed by the principle of no-signaling just corresponds to the algebraic maximum of Bell operator. Then we study the CabeUo＇s argument of Hardy＇s non-locality （a generalization of Hardy＇s argument） and find a similar relation between it and violation of Bell inequality. Finally, we give a simple derivation of the bound of Hardy＇s non-locality under the constraint of information causality with the aid of the above derived relation between Hardy＇s non-locality and Bell operator.     

线列光纤传像束对比度传递函数研究

宽视场成像光谱仪采用线列光纤束进行视场折叠以改进其性能.作为一种特殊的光学元件,线列光纤除了具有传像功能外,还具有离散采样特性,这需要采用新方法评价其成像性能.以对比度传递函数的定义为基础,推导出线列光纤束的对比度传递函数解析表达式,据此研究了线列光纤传像束对比度传递函数的特性.结果表明,在极其靠近Nyquist频率及...