高增益硅超高频功率SIT

采用全自对准介质盖栅工艺，通过合理设计，研制成功一种高增益硅超高频功率ＳＩＴ。在４００ＭＨｚ工作频率、５０Ｖ工作电压下，其输出功率Ｐｏ为４０Ｗ，漏极效率η＿Ｄ接近６０％，功率增益Ｇｐ高达１６ｄＢ。Ｐｏ＝２５Ｗ时，三阶交调３ＩＭ为－１６ｄＢ；Ｐｏ＝２．５Ｗ时，３ＩＭ为－５０ｄＢ。     

与高温超导机制相关的理论研究

高温超导体是一个强关联体系，它向传统的能带论和强关联模型研究提出了严重的挑战，第一性原理的电子结构的计算研究，试图给出反常的色散关系和费米面几何特性，以及大Ｕ修正下的影响等。模型哈密顿的研究，企图概括高温超导的主要物理特征，它主要采用两类方法；一类是严格对角化方法，另一类是量子蒙特卡罗方法，对于高温超导电性机制模型，也作了介绍。     

一类非方系统的Morgan问题 *

讨论一类特殊情形的非方系统的Morgan问题,得到了问题有解的充分必要条件,给出了这一类系统判断其Morgan问题是否有解的算法.     

改进的密封硼硅玻璃CO2波导激光器

渡导CO2激光器具有紧凑、高增益、可调谐等优点，因此引起了人们极大的注意。它将在激光通讯、激光雷达、高分辨率光谱学等方面得到广泛的应用。     

高熵纳米合金在电化学催化中的应用

The implementation of clean energy techniques, including clean hydrogen generation, use of solar-driven photovoltaic hybrid systems, photochemical heat generation as well as thermoelectric conversion, is crucial for the sustainable development of our society. Among these promising techniques, electrocatalysis has received significant attention for its ability to facilitate clean energy conversion because it promotes a higher rate of reaction and efficiency for the associated chemical transformations. Noble-metal-based electrocatalysts typically show high activity for electrochemical conversion processes. However, their scarcity and high cost limit their applications in electrocatalytic devices. To overcome this limitation, binary catalysts prepared by alloying with transition metals can be used. However, optimization of the activity of the binary catalysts is considerably limited because of the presence of the miscibility gap in the phase diagram of binary alloys. The activity of binary electrocatalysts can be attributed to the adsorption energy of molecules and intermediates on the surface. High-entropy alloys (HEAs), which consist of diverse elements in a single NP, typically exhibit better physical and/or chemical properties than their single-element counterparts, because of their tunable composition and inherent surface complexity. Further, HEAs can improve the performance of binary electrocatalysts because they exhibit a near-continuous distribution of adsorption energy. Recently, HEAs have gained considerable attention for their application in electrocatalytic reactions. This review summarizes recent research advances in HEA nanostructures and their application in the field of electrocatalysis. First, we introduce the concept, structure, and four core effects of HEAs. We believe that this part will provide the basic information about HEAs. Next, we discuss the reported top-down and bottom-up synthesis strategies, emphasizing on the carbothermal shock method, nanodroplet-mediated electrodeposition, fast moving bed pyrolysis, polyol process, and dealloying. Other methods such as combinatorial co-sputtering, ultrashort-pulsed laser ablation, ultrasonication-assisted wet chemistry, and scanning-probe block copolymer lithography are also highlighted. Among these methods, wet chemistry has been reported to be effective for the formation of nano-scale HEAs because it facilitates the concurrent reduction of all metal precursors to form solid-solution alloys. Next, we present the theoretical investigation of HEA nanocatalysts, including their thermodynamics, kinetic stability, and adsorption energy tuning for optimizing their catalytic activity and selectivity. To elucidate the structure–property relationship in HEAs, we summarize the research progress related to electrocatalytic reactions promoted by HEA nanocatalysts, including the oxygen reduction reaction, oxygen evolution reaction, hydrogen evolution reaction, methanol oxidation reaction, and CO₂ reduction reaction. Finally, we discuss the challenges and various strategies toward the development of HEAs.     

有限元超收敛新论

本文从三个方面讨论二阶椭圆问题有限元超收敛．1．一致网格上的新超收敛结果．利用新的“投影型插值”,我们解决了高次三角形元的超收敛问题．2．一般网格的超收敛性．利用局部插值处理和局部磨光处理我们获得了整体超收敛性结果．3．关于当前的两种超收敛技巧．Cornell学派利用一个精致的内估计和网格的点对称性,获得了一个“普遍”的结果,中国学派利用两个基本估计和离散Green函数理论获得了令人满意的结果,两者均很复杂．本文综合了两个学派的方法,简洁地证得上述普遍结果．     

显示用胆甾相液晶材料发展现状

介绍了胆甾相液晶显示性能和对液晶材料的要求,分析了近几年高双折射率液晶化合物和手性掺加剂及其胆甾相液晶材料的应用与发展情况,初步阐明了分子结构与液晶性能及其手性掺加剂的HTP值之间的依存关系,为开发新型液晶化合物、手性化合物和胆甾相液晶材料提供了线索。     

γ辐照三烷基氧化膦的红外光谱研究

混合三烷基氧化膦（ＴＲＰＯ）是一种优良的镧系元素和镧元素萃取剂,已用于放废液的α核素的萃取分离。本文用傅里叶红外光谱法研究γ辐照的３０％ＴＰＯ－煤油－ＨＮＯ３体系的辐照稳定性,结果显示,该萃取剂对放射性辐射是稳定的,主要的辐解产物是硝基烷和羟酸。     

高电荷态离子40Arq+与Si表面作用中的电子发射产额

报道了在兰州重离子加速器国家实验室电子回旋共振离子源原子物理实验平台上，用高电荷态⁴⁰Ar^q+(1≤q≤12)离子作用于半导体Si固体表面时的电子发射产额实验测量.实验中，通过改变炮弹离子的电荷态和引出电压选取其不同的势能和动能，系统地研究了入射离子势能沉积和与其在固体中的电子能损对表面电子发射产额的贡献.结果表明，作为引起表面电子发射的两个主要因素，单离子的电子发射产额与炮弹离子在固体表面的势能沉积和电子能损都有近似的正比关系.