电解水制氢的实验研究

搭建了电解水制氢的实验装置,并利用该装置研究了氢气与氧气的产生率与电流及时间的关系,同时测定电解装置的能效因数.     

A Darboux Transformation for the Coupled Kadomtsev--Petviashvili Equation

The coupled Kadomtsev-Petviashvili equation is considered. It is shown that a Darboux transformation can be constructed by means of an elementary approach.     

SU(2)规范场的一系列“无源”解——静点磁荷系的SU(2)势及U(1)势

场与源这一对矛盾双方如何对立与统一是经典电磁场及引力场理论中议论纷云的一个根本问题.非Abel规范场的静无源解(应该说是无外源,但以场自身为源)提供了一个不含奇异点的、场与源互相制约构成自洽稳定的有机统一体的一个值得注意的例子(孤粒子).现有的这种解都是在无外源(实际上以场的奇异点——磁荷为源)的吴杨单位磁荷解([4]的情况a)的基础上加上径向“形状因子”得到的,因此只限于总磁荷为单位值(本文取Schwinger量子化值为磁荷单位)的静同步球对称情况.为了弄清楚更一般     

槽式DSG太阳能集热系统模拟分析

以采用真空集热管的一次通过式槽式DSG太阳能集热器为研究对象。基于集热器管内水工质的流型与传热特性,建立了集热器稳态传热模型,并验证了模型及计算方法的合理性。分析了当出口为400℃过热蒸汽时,集热器传热受太阳辐射强度、管径、水工质入口参数等的影响规律。结果表明集热器的传热效果取决于周围环境的边界条件以及集热器结构参数和水工质运行参数的选取,本文结论为DSG集热器的设计及运行提供了理论参考依据。     

Compensation of body shake errors in terahertz beam scanning single frequency holography for standoff personnel screening

In the terahertz(THz) band, the inherent shake of the human body may strongly impair the image quality of a beam scanning single frequency holography system for personnel screening. To realize accurate shake compensation in imaging processing, it is quite necessary to develop a high-precision measure system. However, in many cases, different parts of a human body may shake to different extents, resulting in greatly increasing the difficulty in conducting a reasonable measurement of body shake errors for image reconstruction. In this paper, a body shake error compensation algorithm based on the raw data is proposed. To analyze the effect of the body shake on the raw data, a model of echoed signal is rebuilt with considering both the beam scanning mode and the body shake. According to the rebuilt signal model, we derive the body shake error estimated method to compensate for the phase error. Simulation on the reconstruction of point targets with shake errors and proof-of-principle experiments on the human body in the 0.2-THz band are both performed to confirm the effectiveness of the body shake compensation algorithm proposed.     

选区激光熔化及热处理工艺对钴铬合金力学性能的影响

系统研究了选区激光熔化（SLM）及热处理工艺对钴铬合金组织与性能的影响。通过设计正交实验,利用EOS M290选区激光熔化设备,优化钴铬合金成型的工艺参数;利用XRD、扫描电镜（SEM）、硬度仪及万能材料试验机对选区激光熔化钴铬合金的显微组织结构、物相组成及力学性能进行观察与测试。研究结果表明,选区激光熔化成型的最佳工艺参数为：扫描间距0.08 mm,扫描速度1110 mm/s,激光功率335 W,能量密度4.8 J/mm2,获得的致密度高达99.18%,且最佳的填充角度为67。SLM成型的钴铬合金的物相主要由相及少量相共存,微观组织由细小均匀的胞状晶及柱状晶构成;其硬度、抗拉强度及延伸率分别为41.0HRC,1032 MPa,10%,断裂机制主要为穿晶脆性断裂。热处理后显微组织发生相变,主要为相及少量相,并产生少量强化相M23C6(M=Cr,Mo,W);其硬度、抗拉强度及延伸率分别提升了6.1%,35.9%和17.6%,断裂机制主要为准解理断裂。     

Behaviour of Self-Standing CVD Diamond Film with Different Dominant Crystalline Surfaces in Thermal-Iron Plate Polishing

Self-standing CVD diamond films with different dominant crystalline surfaces are polished by the thermal-iron plate polishing method. The influence of the dominant crystalline surfaces on polishing etfficiency is investigated by measuring the removal rate and final roughness. The smallest rms roughness of 0.14 μm is measured with smallest removal rate in the films with the initial （220） dominant crystalline surface. Activation energy for the polishing is analysed by the Arrhenius relation. It is found that the values are 170kJ/mol, 222kJ/mol and 214kJ/mol for the film with three different dominant crystalline surfaces. Based on these values, the polishing cause is regarded as the graphitization-controlling process. In the experiment, we find that transformation of the dominant crystalline surfaces from （111） to （220） always appears in the polishing process when we polish the （111） dominant surface.     

类氦离子的KLL双电子复合过程的相对论理论研究

在相对论多组态Dirac-Fock理论基础上，发展了计算双电子复合截面的程序.并以类锂C³⁺，Ar¹⁵⁺，Kr³³⁺和U⁸⁹⁺等离子为例，详细计算了共振双激发态1s2l2l′的辐射衰变率、Auger衰变率及相应的双电子复合截面.对于C⁴⁺，Ar^l6+和Kr³⁴⁺离子的结果与已有的计算和实验结果都能很好地符合；对于U⁹⁰⁺离子，则重点 关键词： 双电子复合 截面 MCDF     

替代法测量微安表内阻的不确定度分析

在测量微安表内阻的众多方法中,替代法是最简单的方法。本文全面分析了影响测量结果不确定度的因素,求出了实验测量的最佳条件,计算了普通仪器组合下测量结果的相对不确定度。     

Cl-ClO催化循环圈的从头算研究

采用分子轨道从头算方法,在B3LYP/6-311 G(3df)和G2水平上研究了极地平流层臭氧损耗的一个基本过程.计算结果明显支持Cl-ClO催化循环圈机理,并且从能量角度解释了了臭氧破坏的基本原因.还对循环圈中各个反应的反应能,生成焓,相对吉布斯自由能做了计算,计算结果相互协调都说明了Cl-ClO催化循环圈破坏臭氧机理的正确性.