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1.
SrS(Cu,Sm)的红外激励上转换发光及光存储特性   总被引:3,自引:0,他引:3  
本文首次报道了SrS(Cu,Sm)的红外激励上转换发光及光存储特生,给出了二种典型样品的光致发光的激光光谱,测定红外激励发光和激励光谱,结果表明SrS9Cu,Sm)具有极好的可擦除可重写的光存储功能,其最长的写入光波段在350nm附近,读出光波长约在800-1400nm附近,发射兰绿光峰波长在515nm附近。  相似文献   

2.
制备了可用于蓝色TFEL的粉末发光材料MGa2S4:Ge(M=Ca,Sr)地其昌体结构进行了X射线分析,测量并其激光光谱和发射光谱,研究了Ce^3+浓度的变化对CaGa2S4:Ce和SrGa2S4:Ce的激光光谱,发射光谱、色纯工及发光强度的影响,同时研究了基质组分的改变对发光特性的影响,结果表明,CaGa2S4:Ce和SrGa2S4:Ce的可发射纯蓝色光,色纯度好,对CaGa2S4:Ce来说,实  相似文献   

3.
对Fe73.5Cu1Mo3Si13.5B9微晶软磁合金的结构及其对合金磁性的影响了研究,结果表明,在最佳磁性能下,晶相点阵常数a=0.2843nm,相当于Fe(Si)固溶体中含Si%(mol/mol):18-20,体积百分数V=74.8%,晶粒尺寸D=14.6nm;残余非晶层厚度δ=1.23nm;当T退火≥560℃时明显有Fe-B化合物析出。Fe73.5Cu1Mo3Si13.5B9合金的磁性不仅与  相似文献   

4.
本文采用了不同温度下两次烧结的新方法,制备了系列X射线影象存储材料BaF_xCl_(2-x):Eu ̄(2+)(x=0.90,0.95,1.00,1.05,1.101.15)。通过改变F/Cl比值,研究了在X射线辐照后BaF_xCl_(2-x):Eu ̄(2+)的热释发光性质,给出了热释发光峰的温度与缺陷种类的关系。最后,我们研究了BaF_xCl_(2-x):Eu ̄(2+)的光激励发光性质,给出了F/Cl比值与光激励发光强度的关系。  相似文献   

5.
采用RF溅射技术制备了SrGa2S4:Ce薄膜,并获得了发射波长为446nm的纯蓝色发光,其CIE色坐标为x=0.14,y=0.09,研究了SrGa2S4:Ce薄膜的激发谱和发射光谱,采用XRD测定了薄膜的晶体结构,采用SEM观察了薄膜的表面形貌,同时着重研究了后退火气氛,温度和时间对薄膜发光特性的影响。  相似文献   

6.
用XRD法研究了退火Fe73.5Cu1Nb3Si13.5B9合金中α-Fe(Si)晶化相的有序化过程.结果表明,Fe73.5Cu1Nb3Si13.5B9非晶合金在490℃,1h退火后,α-Fe(Si)晶化相是具有DO3结构的有序相,有序畴为球形,直径为7.0nm,它随退火温度的升高而长大,在590℃退火后达10.9nm,与α-Fe(Si)的尺寸相当.此时,α-Fe(Si)的有序度为0.8在850℃,1h退火后,α-Fe(Si)的DO3超点阵线条消失.在550℃等温退火时,α-Fe(Si)的DO3有序畴先为椭球状,于60min退火后形成球状,直径为10nm.  相似文献   

7.
用XRD法研究了退火Fe73.5Cu1Nb3Si13.5B9合金中α-Fe(Si)晶化相的有序化过程,结果表明,Fe73.5Cu1Nb3Si13.5B9非晶合金在490℃,1h退火后,α-Fe(Si)晶化相是具有DO3结构的有序相,有序畴为球形,直径为7.0nm,它随退炎温度的升颃是长大,在590℃退火后达10.9nm,与α-Fe(Si)的尺寸相当,此时α-Fe(Si)的有序度为0.8,在850℃  相似文献   

8.
本文用XRD和TEM研究了Fe73.5Cu1Mo3Si13.5B9非晶合金在520℃20-120min退火后形成的纳米晶结构。结果表明,晶化相为局部具有DO3超结构的α-Fe(Si),尺寸约为14nm,α-Fe(Si)晶粒由DO3有序区和序区组成。随退火时间的延长,α-Fe(Si)的体积分数,Si含量及DO3有序区尺寸增加。在退火时间为60min时,残余非晶相处于一特殊结构状态。α-Fe(Si)相  相似文献   

9.
Cu和Nb对非晶态Fe—Si—B合金等温晶化过程的影响   总被引:2,自引:0,他引:2  
采用示差扫描量热卡计(DSCI)得到了非晶态Fe-Si-B合金加入Cu和Nb后的等温晶化放热曲线,结合X射线衍射(XRD)分析,明确了Cu和Nb在形成纳米α-Fe(Si)晶体相时的作用。此外,非晶态Fe76.5Si13.5B9Cu1Nb3等温化的α-Fe(Si)放热峰呈明显的非对称形状。  相似文献   

10.
王永生  熊光楠 《功能材料》1994,25(6):518-522
本文研究了光激励发光材料BaFCl:Eu中的发光中心。在不同的反应气氛下BaFCl:Eu具有不同的发光性质。利用光谱的方法、X射线光电子能谱的方法,研究了在不同条件下制备的BaFCl:Eu样品中,稀土离子Eu的性质。  相似文献   

11.
凝固科学技术与材料   总被引:8,自引:0,他引:8  
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。  相似文献   

12.
13.
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.  相似文献   

14.
单贺飞 《包装工程》2022,43(18):341-349
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。  相似文献   

15.
Error and uncertainty in modeling and simulation   总被引:1,自引:0,他引:1  
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.  相似文献   

16.
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.  相似文献   

17.
18.
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.  相似文献   

19.
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.  相似文献   

20.
罗林  黄志雄赵颖 《功能材料》2007,38(A09):3470-3472
SMC/BMC废弃物对工业及环境造成了很大影响,指出了SMC/BMC回收再利用的紧迫性。通过对目前国际上SMC/BMC回收再利用的3种典型途径优缺点的对比,参照国外SMC/BMC回收再利用的先进方法,对我国SMC/BMC回收再利用提供了可行的建议.  相似文献   

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