Bi12TiO20晶体的全息性能

Ｂｉ１２ＴｉＯ２０晶体是一种优良的全息记录材料。本论文对纯Ｂｉ１２ＴｉＯ２０和掺Ｃｅ∶Ｂｉ１２ＴｉＯ２０晶体的衍射效率、半波电压、旋光度等性能进行了测试，并讨论了掺入的Ｃｅ对晶体性能的影响，Ｃｅ＾４＋离子在晶体中取代Ｂｉ＾３＋离子形成新的区域中心。此外还探讨了Ｔｉ原子对晶体旋光度的影响，认为Ｂｉ１２ＴｉＯ２０晶体旋光度远小于Ｂｉ１２ＳｉＯ２０、Ｂｉ１２ＧｅＯ２０的根本原因在于Ｔｉ原子的性质和极化不     

无Co混合导电型陶瓷透氧膜的制备和性质研究

首次合成了Ｓｒ１０－ｎ／２ＢｉｎＦｅ２０Ｏｍ（ｎ＝２，４，６，８，１０等）系列氧化物透氧膜，它们具有较高的透氧能力，其中，样品ｎ＝１０在１１００Ｋ时的透氧率为０．９０ｍｌ（ＳＴＤ）／（ｃｍ２·ｍｉｎ），比Ｓｒ１－ｘＢｉｘＦｅＯ３高约两倍．Ｓｒ１－ｘＢｉｘＦｅＯ３（ｘ＝０．１，０．３，０．５）系列的透氧率随Ｂｉ含量增加而增大．通过两个系列氧化物的ＸＲＤ和化学组成的对比，发现Ｂｉ离子含量和晶格空位浓度对透氧能力大小起决定性作用．     

Li1+2x+yAlxNdyTi2-x-ySixP3-xO12系统的锂快离子导体研究

Ｌｉ１＋２ｘ＋ｙＡｌｘＮｄｙＴｉ２－ｘ－ｙＳｉｘＰ３－ｘＯ１２锂快离子导体可以用精选的天然高岭石Ａｌ４「Ｓｉ４Ｏ１０」（ＯＨ）８为起始原料，经与Ｌｉ２Ｃｏ３、ＴｉＯ２、ＮＨ４Ｈ２ＰＯ４进行高温（８００－１０００℃固相反应约２０ｈ而制得，一个空间群属于Ｒ３Ｃ的固溶体导电相可在ｙ＝０．５，ｘ≤０．３和ｙ＝１．０，ｘ≤０．４的组成范围内发现，该盯具有较好的电导性较低的活化能，起始组成ｙ＝１．０，ｘ＝０．     

立方A^4＋M^5＋2O7型化合物与新型负热膨胀材料

概述了立方Ａ＾４＋Ｍ＾５＋２Ｏ７型化合物的结构特点，讨论了ＡＶ２－ｘＰｘＯ７型（Ａ＝Ｚｒ或Ｈｆ；ｘ＝０．１～１．２）及其部分取代的Ａ＾４＋１－ｙＢ＾４＋ｙＶ２－ｘＰｘＯ７型（Ｂ＝Ｔｉ，Ｃｅ，Ｔｈ，Ｕ，Ｍｏ，Ｐｔ，Ｐｂ，Ｓｎ，Ｇｅ或Ｓｉ；ｙ＝０．１～０．４）和Ａ＾４＋１－ｙＣ＾１＋ｙＤ＾３＋ｙＶ２－ｘＰｘＯ７型（Ｃ为碱金属元素，Ｄ为稀土金属元素）材料的负热膨胀性能。     

Bi2O3-SiO2系统的相关系和析晶行为的研究进展

本文介绍了Ｂｉ２Ｏ３－ＳｉＯ２系统的研究进展。首先对该系统的稳定相平衡和亚稳定相平衡进行了综述，然后讨论了该系统中化合物Ｂｉ１２ＳｉＯ２０、Ｂｉ４Ｓｉ３Ｏ１２和Ｂｉ２ＳｉＯ５的结构、性能、生长、应用等方面的情况，预计Ｂｉ２ＳｉＯ５将成为一种有前途的新功能晶体。     

一种用于宽带温度稳定光隔离器的新型磁光材料

以Ｂｉ２Ｏ３／Ｂ２Ｏ３为主要助熔剂,用改进的高温助熔剂法生长出一种新型掺铋 事稀土铁石榴石（ＨｏＹｂＢｉ）３Ｆｅ５Ｏ１２单晶,研究了磁光性能,法拉第旋转温度和波长特性在１０－１１０℃,单昌的法拉第旋转温度系数Ｓ＝θＦ＾－１（ｄθＦ／ｄＴ）在λ＝１．５５μｍ时为４．６×１０＾－４Ｋ＾－１,比ＹＩＧ单晶的法拉第旋转温度系数小,在λ＝１．５５μｍ时,（ＨｏＹｂＢｉ）３Ｆｅ５Ｏ１２单晶的法拉第旋转波长系数     

Bi2（Te1—xSex）3单晶生长热力学研究

本工作研究了Ｂｉ－Ｆｅ－Ｓｅ三元相在富Ｂｉ２Ｔｅ３区的相图。测定了Ｂｉ２Ｔｅ３和Ｂｉ２Ｓｅ３从５５０℃到它们的熔点范围内的等浓度线,用移动加热器（ＴＨＭ）法生长Ｂｉ２（Ｔｅ１－ｘＳｅｘ）３（ｘ＝０．０２５和ｘ＝０．０５）。用霍尔（Ｈａｌｌ）效应测定这些化合物在富Ｔｅ区的固线,研究表明,可再生法生长热力学定义的单晶是可能的。     

掺铋钇铁石榴石光吸收谱的理论计算

利用ＤＶ－Ｘα方法分别计算了Ｆｅ＾３＋Ｏ＾２－６和Ｆｅ＾３＋Ｏ＾２－４原子族的能态密度和能级，在能级图的基础上，给出了０．５－０．９μｍ（１．６ｅｒ－２．３ｅｖ）范围内Ｂｉ－ＹＩＧ与吸收有关的跃迁能级，振子强度和跃迁线宽，并计算了相应的吸收谱，理论计算与实验结果符合较好。     

光电导型混晶Si1-xGex波导探测器

首次报导了光电导型混晶Ｓｉ－ｘＧｅｘ波导探测器。混晶Ｓｉ１－ｘＧｅｘ是在硅基ＳｉＯＮ／ＳｉＯ２／Ｓｉ上用快速加热超低压化学气相淀积生长并经６５０℃退火３０ｍｉｎ得到的。探测器宽１０μｍ,长２ｍｍ。探测器加２０Ｖ偏置电压是,探测灵敏在０．０２２－０．０１０Ａ／Ｗ之间。混晶Ｓｉ１－ｘＧｅｘ造成探测器的光谱响应曲线发生蓝移。当锗组分ｘ＝０．３５、０．４、０．５、和０．６时,探测器峰值波长分别对应为８７５     

掺杂BaCeO3和SrCeO3在氧,氢及水气气氛下的电导性能

掺杂碱土金属铈酸盐系统：ＭＣｅ１－ｘＲｘＯ３－ｘ／２（Ｍ＝Ｂａ，Ｓｒ；Ｒ＝Ｙｂ，Ｙ，Ｇｄ，Ｌａ；ｘ＝０．０１～０．１０）可由固相反应制得单相化合物，Ｘ射线衍射分析表明，掺杂元素及掺杂量对掺杂ＢａＣｅＯ３和ＳｒＣｅＯ３的晶体结构影响不大。用复数阻抗谱研究了在氧、氢、水气气氛下的电导性能。在各种气氛下ＭＣｅ０．９５Ｙｂ０．０５Ｏ２．９７５（Ｍ＝Ｂａ，Ｓｒ）的电导率最大。根据测试结果，结合缺陷化学理论讨     

凝固科学技术与材料

从凝固科学与实践发展的角度介绍了当前凝固材料体系的基本框架和凝固科学主要发展阶段的基本理论。作为材料科学与工程的基本组成，凝固科学技术正在现代科学理论的基础上针对传统材料的改性提高和新材料的发展需求，以控形、控构、控性为目标开展优质铸件的定向、晶体生长、快凝、深过冷及各种新型和超常领域凝固过程的研究，并介绍了其中某些方面和展望了可能的发展趋势。     

Development and challenges of planning and scheduling for petroleum and petrochemical production

Production planning and scheduling are becoming the core of production management, which support the decision of a petrochemical company. The optimization of production planning and scheduling is attempted by every refinery because it gains additional profit and stabilizes the daily production. The optimization problem considered in industry and academic research is of different levels of realism and complexity, thus increasing the gap. Operation research with mathematical programming is a conventional approach used to address the planning and scheduling problem. Additionally, modeling the processes, objectives, and constraints and developing the optimization algorithms are significant for industry and research. This paper introduces the perspective of production planning and scheduling from the development viewpoint.     

江澳两地高校文创设计的协同研究与商业实践

目的 探索江门世遗文化的传承、发展和转化的新思路,践行国家在《粤港澳大湾区发展规划》纲要中要求江门承担与港澳地区文化创意合作与开发任务的分工。方法 与澳门高校紧密合作,开展专业培训课程,以开平碉楼为例,从人文视角开展设计研究,梳理开平碉楼的文化脉络,把世遗文化的元素和其背后的文化融入文创产品中,提升文创产品的附加值,推动当地文创产业结构的变革。结果 两地高校构建了稳定的科研团队,开设长期有效的设计培训课程,与景区建立了研究协作关系,帮助景区构建了一套产销研的商业模式。结论 以跨区域高校合作为平台,以文创产品为抓手,依托江澳两地的资源优势,可以构建江门世遗文化全新的品牌形象,最终推动开平世遗文化的活化。     

Creation and motion of dislocations and fracture in metal and silicon crystals

By making a step on one surface ( ) of a rectangular small paralellepiped copper crystal, dislocations could be created by the molecular dynamic method. The dislocation created was not a complete edge dislocation but a pair of Heidenreich-Shockley partial dislocations. Each time a dislocation was created, the stress on the surface was released. Small copper crystals having a notch were pulled (until fracture), compressed and buckled by use of the molecular dynamic method. An embedded atom potential was used to represent the interaction between atoms. Dislocations were created near the tip of the notch. A very sharp yield stress was observed. The results of high speed deformations of pure silicon small crystals using the molecular dynamics are presented. The results suggest that plastic deformation may be possible for the silicon with a high speed deformation even at room temperature. Another small size single crystal, the same size and the same surfaces, was compressed using molecular dynamic method. The surfaces are {110}, {112} and {111}. The compressed direction was [111]. It was found that silicon crystals are possible to be compressed with a high speed deformation. This may suggest that silicon may be plastically deformed with high speed deformation.     

The Candela and Photometric and Radiometric Measurements

The national measurement system for photometric and radiometric quantities is presently based upon techniques that make these quantities traceable to a high-accuracy cryogenic radiometer. The redefinition of the candela in 1979 provided the opportunity for national measurement laboratories to base their photometric measurements on optical detector technology rather than on the emission from high-temperature blackbody optical sources. The ensuing technical developments of the past 20 years, including the significant improvements in cryogenic radiometer performance, have provided the opportunity to place the fundamental maintenance of photometric quantities upon absolute detector based technology as was allowed by the 1979 redefinition. Additionally, the development of improved photodetectors has had a significant impact on the methodology in most of the radiometric measurement areas. This paper will review the status of the NIST implementation of the technical changes mandated by the 1979 redefinition of the candela and its effect upon the maintenance and dissemination of optical radiation measurements.     

Error and uncertainty in modeling and simulation

This article develops a general framework for identifying error and uncertainty in computational simulations that deal with the numerical solution of a set of partial differential equations (PDEs). A comprehensive, new view of the general phases of modeling and simulation is proposed, consisting of the following phases: conceptual modeling of the physical system, mathematical modeling of the conceptual model, discretization and algorithm selection for the mathematical model, computer programming of the discrete model, numerical solution of the computer program model, and representation of the numerical solution. Our view incorporates the modeling and simulation phases that are recognized in the systems engineering and operations research communities, but it adds phases that are specific to the numerical solution of PDEs. In each of these phases, general sources of uncertainty, both aleatory and epistemic, and error are identified. Our general framework is applicable to any numerical discretization procedure for solving ODEs or PDEs. To demonstrate this framework, we describe a system-level example: the flight of an unguided, rocket-boosted, aircraft-launched missile. This example is discussed in detail at each of the six phases of modeling and simulation. Two alternative models of the flight dynamics are considered, along with aleatory uncertainty of the initial mass of the missile and epistemic uncertainty in the thrust of the rocket motor. We also investigate the interaction of modeling uncertainties and numerical integration error in the solution of the ordinary differential equations for the flight dynamics.     

PSD和PWELCH函数的分析改进及应用

针对MATLAB中两个内建功率谱密度计算函数psd()和pwelch()计算结果迥异的现象,在功率谱密度估计理论的基础上,根据经典的周期图理论和Welch平均周期图方法,通过详细分析源程序,解析计算方法,发现psd()计算的并不是工程单边功率谱密度,而是采样信号双边谱,故与pwelch()结果迥异,另外pwelch()不能对分段信号数据进行预处理。就上述不足提出了相应的改进措施,比较验证表明改进措施行之有效。     

Density and viscosity of tetralin and trans-decalin

New measurements are reported for the density and viscosity of tetralin and trans-decalin. The density was determined from room temperature to 60°C for tetralin and to 95°C for trans-decalin. The kinematic viscosity was measured up to temperatures slightly above 100°C. Our results improve upon the values recommended by the American Petroleum Institute for these liquids.