硅基PbSe/BaF_2/CaF_2薄膜及其光电特性

采用分子束外延方法在 Si(111)衬底上生长了 Pb Se/ Ba F2 / Ca F2 薄膜 ,扫描电镜和 X-光衍射分析显示 ,通过生长 Ba F2 / Ca F2 缓冲层的方法 ,在 Si(111)衬底上外延的 Pb Se薄膜晶体质量高 ,Pb Se表面光亮 ,无开裂现象发生 ,X-光衍射峰峰宽窄 (15 3arcs) .外延生长的 Pb Se薄膜被应用于制作光电二极管 ,首次采用热蒸发金属铝膜在 Pb Se表面形成 Al- Pb Se肖特基结光电二极管 ,获得了比 Pb- Pb Se肖特基结更为稳定和理想的电流 -电压特性曲线     

B超诊断仪凸阵阵元高度方向复合聚焦声场的研究

文章研究B超诊断仪凸阵阵元高度方向复合聚焦声场的计算推导了方便实用的计算公式。然后进行了实验和数值计算,实验结果与理论预测相当吻合,偏差不超过7％。最后在计算机上进行数值仿真,进一步研究了声透镜的几何参数影响声场参数的规律。     

酸洗前处理对叠层片式电感器焊接性的影响

采用电子扫描电镜和能谱分析研究了叠层片式电感器(MLCI)端电极的三层结构对焊接性的影响。利用氢氟酸(HF)具有强氧化性的特点对产品端电极银层进行微蚀前处理以起到整平作用,利于镀层的生长。试验结果证明前处理酸洗工艺能够有效改善产品镀层的焊接性。使用质量分数2%的HF进行酸洗,能够有效去除端电极银镀层上的玻璃相成分(SiO2),从而使电感器镀层表面上锡覆盖率大于90%。     

基于CIM的电网规划管理决策辅助系统

针对电网规划所面临的多部门、多层级的低效收资,设计并编程实现了基于CIM的电网规划管理决策辅助系统。该系统以基于CIM模型的数据库设计为底层基础,构建的数据库定期由GIS系统、EMS系统和外部导入进行更新,实现数据共享。功能层面主要分为评估分析模块、规划研究模块以及数据发布模块。评估分析模块主要支持对现状电网供电能力和运行水平的评估工作;规划研究模块主要支持规划设计中的辅助决策工作和规划评价工作;数据发布模块主要支持上述两个模块中数据的发布查询功能。以某地区局部电网为例,验证了该系统的高效实用性以及对电网规划工作良好的指导意义。     

安徽省煤电机组超低排放改造及CEMS验收问题分析

对安徽省已提前完成超低排放改造任务的67台（36 490 MW）煤电机组的SO₂、NO_x和烟尘超低排放改造技术路线、改造的经济性、改造后排放浓度及减排量以及改造后3种污染物在线监测系统（CEMS）验收中的问题进行分析。研究表明：安徽省燃煤电厂超低排放改造主要以湿式电除尘、低低温电除尘和超净电袋为核心的3条典型技术路线。1000MW机组改造经济性最高,其次为600MW和300MW机组。超低排放改造对全省电厂烟气污染物减排显著,污染物之间协同脱除效果良好。现行的气态污染物监测仪器、滤尘材料及测试方法均不能很好地满足改造后污染物CEMS验收的测试准确度要求,建议超低排放改造机组的烟尘验收选用低浓度粉尘测量自动取样系统和设置空白实验修正;SO₂验收需采用紫外或红外烟气分析仪,采样管路需要高温伴热;NO_x验收应根据SCR脱硝出口和总排口NO_x浓度测试数据相互佐证。     

Language acceptability of finite automata based on theory of semi‐tensor product of matrices

Using the theories of many‐valued logic and semi‐tensor product of matrices (STP), this paper investigates how to mathematically determine whether or not a regular language is recognized by finite automata (FA). To this end, the dynamic behaviour of FA is first formulated as bilinear dynamic equations, which provides a uniform model for deterministic and non‐deterministic FA. Based on the bilinear model, the recognition power of FA understanding of regular languages is investigated and several algebraic criteria are obtained. With the algebraic criteria, to judge whether a regular sentence is accepted by a FA or not, one only needs to calculate an STP of some vectors, rather than making the sentence run over the machine as traditional manners. Further, the inverse problem of recognition is considered, an algorithm is developed that can mathematically construct all the accepted sentences for a given FA. The algebraic approach of this paper may be a new angle and means to understand and analyse the dynamics of FA.     

机床结构建模的研究与应用

本文探讨了一种考虑结合部动态特性的机床动力学模型的建立方法。该方法基于对结合部动态特性的研究,应用结合面通用动态数据获得结合部的物理参数,并利用设计图纸资料来建立机床结构的动力学模型。首先根据结合部的结合方式与结合条件,分析计算出结合部各结合面的压力分布,从而得到各结合面的等效物理参数,再由结合部的结构型式,导出结合部的物理参数。对机床结构中几种典型的结合部结构型式,分析了其结合部参数获取的途径和方法。作为实际应用,根据上述的建模方法,建立起昆明铣床厂生产的×8132万能工具铣床的整机动力学模型,将该机床简化为21个自由度的振动系统,利用FORTRAN语言编制的计算机程序,在CM—24微机上完成了固有特性与动态响应的计算,计算结果与激振试验数据在信号处理机7T17上分析得到的结论是相吻合的,所建立的动力学模型能够较好地模拟实际机床结构的动态特性,从而证明了本建模方法的正确性与实用性。     

Toluenesulfonate-acyl esters of ethylene glycol and other 1,2-diols as industrial antioxidants with cupric ion

Ethylene glycol esters of soybean oil FA increased in viscosity much more slowly than methyl or glycerol esters when oxidized at 105°C in the presence of flowing air and colloidal copper. This increased stability was caused by a minor constituent of the ethylene glycol esters, which was shown by MS to be a mixed ethanediol fatty acylate p-toluenesulfonate (EFAT). The p-toluenesulfonate group came from the catalyst used in the formation of the ethylene glycol esters. EFAT was quantified by UV spectrometry, HPLC, or GC of the acyl group that it contains. EFAT could be synthesized in good yield by reacting ethylene glycol, a FA, and p-toluenesulfonic acid (TSA) in a 1∶1∶1 molar ratio using a benzene azeotrope to remove water of esterification. EFAT increased the time required for the polymerization of soybean oil by about 27 times but required concentrations of 2–5% by weight. EFAT made with a variety of FA were active in delaying viscosity increase. Ethyl and decyl p-toluenesulfonate were inactive. Replacing ethylene glycol by glycerol and 1,2-propylene glycol but not by 1,3-propylene glycol resulted in active EFAT. TSA itself delayed the polymerization of soybean oil, especially in the presence of free ethylene glycol and FA, but this probably was caused by formation of EFAT during the oxidation test. Colloidal copper could be replaced by cupric ion. EFAT-copper appeared to act as an antioxidant by destroying hydroperoxides without initiation of free radical chains.     

Effects of Subchronic Samarium Exposure on Testicle Tissue of Mice

Effects of Subchronic Samarium Exposure on Testicle Tissue of Mice