Mixed Symmetry Isomeric States in Nuclei

Mixed symmetry states are studied in the framework of the neutron-proton interacting boson model.It is found that some of the mixed symmetry states with moderate high spins change very fast with respect to the Majorana interaction.Under certain conditions,they become the yrast state or yrare state.These states are difficult to decay and become very stable.This study suggests that a possible new mode of isomers may exist due to the special nature in their proton and neutron degrees of freedom.     

教学用自组式傅里叶变换光谱仪

对原有的傅里叶变换光谱实验进行了全面的升级改造，研制了一种新型的教学用自组式傅里叶变换光谱仪，波长精度较原有实验提高了两个数量级，由该仪器构成的傅里叶变换光谱实验内涵丰富，不但可以使学生学习一种重要的光谱技术，更可以很好地培养学生综合运用所学知识解决实际问题的能力。     

基于云模型的自适应量子免疫克隆算法

利用云模型能够兼顾随机性和模糊性的品质,提出一种基于云模型的自适应量子免疫克隆算法.使用云算子代替通用的量子旋转门这一量子进化算法核心算子用于寻优变异操作;通过控制云算子间的协作,实现算法在进化过程中对搜索范围的动态调整,使算法具有较强的全局搜索能力;同时,补充针对性的优化方案,有效避免了算法陷入局部最优.对标准数值优化问题的仿真对比实验表明,该算法具有寻优能力强、搜索精度高、稳定度好等优点;对非线性系统的参数估计仿真实验,该算法也取得了对参数的高精度有效估计.     

Effects of Bond Alternation on the Ground-State Phase Diagram of One-Dimensional XXZ Model

The ground-state properties and quantum phase transitions (QPTs) of the one-dimensional bond-alternative XXZ model are investigated by the infinite time-evolving block decimation (iTEBD) method. The bond-alternative effects on its ground-state phase diagram are discussed in detail. Once the bond alternation is taken into account, the antiferromagnetic phase (Δ > 1) will be destroyed at a given critical point and change into a disordered phase without nonlocal string order. The QPT is shown to be second-order, and the whole phase diagram is provided. For the ferromagnetic phase region (Δ < -1), the critical point r^c always equals 1 (independent of Δ), and the QPT for this case is shown to be first-order. The dimerized Heisenberg model is also discussed, and two disordered phases can be distinguished by with or without nonlocal string orders. Both the bipartite entanglement and the fidelity per site, as two kinds of model-independent measures, are capable of describing all the QPTs in such a quantum model.     

镜像系统和镜像天线

对电荷电流体系在理想导体平面所形成的镜像系统的各物理量作了全面分析，并得出镜像天线的结果。     

个人中子剂量气泡探测器研制

中子固体气泡探测器被认为是唯一能够满足国际辐射防护委员会ICRP60要求的个人中子剂量计，它具有从低能中子到高能中子的平坦响应曲线和对γ射线不灵敏的优点.本工作将过热液滴均匀地分布在一种软聚合物中，制成了个人中子气泡剂量计,其灵敏度达到每毫雷姆40个气泡.还介绍了个人中子剂量气泡探测器的原理和制作过程.Neutron solid bubble detector was considered as a unique one for meeting the need of the personal neutron dosimeter recommended by International Committee of radiation protection,ICRP60.It has the flat response for neutron from low energy to high energy,and insensitive for gamma rays. In this work,superheated liquid drops were dispersed into a kind of soft polymer homogeneously.A personal neutron bubble dosimeter has been made,and the sensitivity reached to about 40bubbles/mrem.The principle and the processing procedure of bubble detector were also introduced in this paper.     

煤直接制甲烷系统的热力学分析

通过Ca基吸收剂的引入,将煤的气化反应、甲烷化反应和CO₂吸收反应集成在同一反应器内,形成煤直接制甲烷系统,可缩短传统煤制甲烷系统流程,提高转化效率。分析了热力学平衡状态下温度、压力、Ca/C比和H₂O/C比对气体产物产量的影响。结果表明降低反应温度和提高反应压力有利于甲烷的产生,而Ca/C比和H₂O/C比的选取存在最优值,得到了煤直接制甲烷体系较为适宜的反应条件为:500～700℃,5～10 MPa,Ca/C=0.5,H₂O/C=1。     

超薄前投激光显示系统研制

为了解决光学系统投影厚度过大问题,采用自由曲反射面结合非球面设计方法设计出超短距离、超广角投影显示系统,其屏幕投影距离小于20 cm。为解决激光色域系统转换,建立了激光三基色与荧光粉三基色色域变换与扩展的理论模型并搭建了基于DSP高速图像处理芯片为核心的颜色变化实时硬件处理试验开发系统。通过该系统可以调试不同颜色系统转换算法,验证转换模型的正确性,并为实现专用颜色转模块提供了开发平台。     

金属线膨胀系数测定实验的改进及进一步研究

为了更好地研究金属线膨胀系数在一定温度区间的变化情况,并进一步研究在加热过程中,待测金属热应力、热应变的变化规律,本文在传统的蒸汽喷射加热仪的基础上,组合运用了粘滞系数实验、表面张力实验以及温度传感器实验中的部分实验仪器,测量并计算了相关的物理量,得到了相关性较理想的拟合直线,并通过对比实验进一步论述了该方法的可行性。     

土壤/沉积物中重金属元素分析的前处理技术研究进展

概述了近年来土壤/沉积物样品中重金属元素分析的前处理技术,包括电热板法、微波消解法、高压密闭消解法和碱熔法等,对各种前处理方法的优缺点进行了比较,并对土壤/沉积物样品中重金属元素的前处理技术研究方向进行了展望。