博莱霉素A_5与DNA结合序列特异性研究

利用荧光淬灭法研究了博莱霉素Ａ５与小牛胸腺ＤＮＡ及ＤＮＡ类似物多聚ｄＧＣ、多聚ｄＡＴ的相互作用，其作用力为疏水作用及氢键，结合常数分别为０．５７×１０５，１．０７×１０５，０．４７×１０５ｍｏｌ－１Ｌ，每结合一个博莱霉素Ａ５所需碱基对数分别为２２～２３，５～６，２７～２８，上述结果表明博莱霉素Ａ５与ＤＮＡ的结合具有ＧＣ序列特异性     

HPLC-MS/MS测定保健食品中的镇静催眠类药物

建立了液相色谱串联质谱法测定保健食品中苯巴比妥、艾司唑仑、地西泮等13种镇静催眠类药物的方法,优化了样品前处理方法及液相色谱串联质谱测定条件.采用甲醇为提取溶剂,超声处理,液相色谱串联质谱检测.结果表明：本方法测定13种镇静催眠类药物的线性范围均为0.04-5.0μg/mL,检出限在1.0-10.0mg/kg之间,3个水平的加标回收率在82.5％-96.9％％之间.     

Reactively sputtered Fe3 O4 -based films for spintronics

Half metallic polycrystalline, epitaxial Fe3O4 films and Fe3O4 -based heterostructures for spintronics were fabricated by DC reactive magnetron sputtering. Large tunneling magnetoresistance was found in the polycrystalline Fe3O4 films and attributed to the insulating grain boundaries. The pinning effect of the moments at the grain boundaries leads to a significant exchange bias. Frozen interfacial/surface moments induce weak saturation of the high-field magnetoresistance. The films show a moment rotation related butterfly-shaped magnetoresistance. It was found that in the films, natural growth defects, antiphase boundaries, and magnetocrystalline anisotropy play important roles in high-order anisotropic magnetoresistance. Spin injection from Fe3O4 films to semiconductive Si and ZnO was measured to be 45% and 28.5%, respectively. The positive magnetoresistance in the Fe3O4 -based heterostructures is considered to be caused by a shift of the Fe3O4 e g ↑ band near the interface. Enhanced magnetization was observed in Fe3O4 /BiFeO 3 heterostructures experimentally and further proved by first principle calculations. The enhanced magnetization can be explained by spin moments of the thin BiFeO 3 layer substantially reversing into a ferromagnetic arrangement under a strong coupling that is principally induced by electronic orbital reconstruction at the interface.     

重叠网格方法的研究进展

从网格装配和插值计算两个主要方面对现有的重叠网格方法进行了综述.首先,从挖洞方法和建立嵌入网格关系环节的寻点技术出发归纳和介绍了网格装配方法;其次,介绍了数值迭代过程中的插值计算方法,并特别讨论了插值守恒性以及插值计算精度等问题;另外,对重叠网格方法的并行计算和应用成果也作了介绍;最后,通过总结认为重叠网格方法在改进网格装配方法、改善插值和并行计算效率等方面仍需进一步研究.     

扫频光学相干层析成像系统的波数校正与相位测量研究

相位敏感光学相干层析成像(OCT)系统可以用于高灵敏度的相位探测,在细胞分析、材料检测等方面具有重要应用,但扫频光源的不稳定性会影响扫频OCT系统的相位测量精度.本文提出了一种基于马赫-曾德尔干涉仪(MZI)时域相位信息的波数校正方法.利用MZI时域包裹相位的互相关运算确定各采集波数序列的相对偏移量,鉴于时域包裹相位的非严格周期特征,可确定偏移量的大小不受限制.依据相对偏移量对各序列信号进行时域同步,并基于同步后的MZI时域解包裹相位实施待测干涉信号在位相域的等间隔重采样.基于所提出的波数校正方法,实施了各扫频序列波数偏移量的校正,开展了基于位相信息的光程重复性测量实验.结果表明,即使在不稳定扫频光源的前提下,也能获得高精度的相位测量结果.     

地方高校物理学高质量课程思政建设如何回答好基础三问

全面推进高质量课程思政建设是落实立德树人根本任务的战略举措,也是提升课程建设质量、提高人才培养质量的重要环节.山西大学物理电子工程学院充分发挥物理学科特色优势,着力探索“1+3+3”的高质量课程思政建设模式,即以突出学生课堂主体地位,培根铸魂、立德树人为一条贯穿线,回答课程思政“为什么”“讲什么”“怎么讲”三个基本问题,从价值塑造、知识传授、能力培养三方面的需求出发,探索出物理学专业高质量课程思政落地实践模式.     

Mechanically tunable metamaterials terahertz dual-band bandstop filter

We experimentally demonstrate a mechanically tunable metamaterials terahertz(THz) dual-band bandstop filter. The unit cell of the filter contains an inner aluminum circle and an outside aluminum Ohm-ring on high resistance silicon substrate. The performance of the filter is simulated by finite-integration-time-domain(FITD) method. The sample is fabricated using a surface micromachining process and experimentally demonstrated using a THz time-domain-spectroscopy(TDS) system. The results show that, when the incident THz wave is polarized in y-axis, the filter has two intensive absorption peaks locating at 0.71 THz and 1.13 THz, respectively. The position of the high-frequency absorption peak and the amplitude of the low-frequency absorption peak can be simultaneously tuned by rotating the sample along its normal axis.The tunability of the high-frequency absorption peak is due to the shift of resonance frequency of two electrical dipoles,and that of the low-frequency absorption peak results from the effect of rotationally induced transparent. This tunable filter is very useful for switch, manipulation, and frequency selective detection of THz beam.     

一维链状卤化亚铜化合物的溶剂热原位合成、 结构及性质

采用溶剂热原位反应合成了一例具有一维铜卤链结构的化合物(C₁₀H₂₂N₂)₃[Cu₉I₁₄Br](C₁₀H₂₂N₂=N,N'-二乙基三乙烯二胺阳离子). 利用X射线单晶衍射、 元素分析、 粉末X射线衍射及红外光谱等测试手段对化合物进行了表征. 测试结果表明, 化合物属于单斜晶系, C2/c空间群, a=2.6233(5)nm, b=1.6299(3)nm, c=1.6707(3)nm, β=117.31(3)°, V=6.347(2) nm³. 化合物的结构由一维的铜卤链和有机模板剂构成, 其中有机模板剂是通过三乙烯二胺和乙醇烷基化反应得到的有机季铵盐阳离子. 该化合物在室温下表现出较好的光致发光性质.     

基于欠采样技术的束流相位测量电子学系统设计北大核心CSCD

采用欠采样技术为中国散裂中子源(CSNS)直线加速器研制了全数字化束流相位测量电子学系统。介绍了该系统的测量原理、整体设计情况,并进行了实验测试。测试采用324 MHz,100 mVpp的正弦信号,测试结果显示相位分辨率优于0.1°,通道间相位不一致性可控制在±0.2°以内,满足设计指标要求。     

15％哒螨灵乳油的气相色谱测定分析

采用气相色谱分析法,以实验室较常用AgilentDB -1毛细管色谱柱为分离柱,选择氢火焰离子化检测器,建立一种适合实验室开展哒螨灵质量分数检测的分析方法,经保留时间定性确证,峰面积外标法进行定量分析.结果表明,哒螨灵的线性相关系数为0.99913;变异系数为0.21％;平均回收率为98.38％.