MRI相关定量参数在肩峰下撞击综合征诊断中的价值及与肩关节功能、治疗效果的关系

为分析MRI相关定量参数对肩峰下撞击综合征(SIS)的诊断价值,本研究将56例SIS患者设为SIS组,同期56例健康体检者设为对照组,对比了两组对象的一般资料、肩关节功能评分(Constant评分)及MRI相关定量参数水平,探讨了MRI定量参数与Constant评分、SIS发病相关影响因素、治疗效果的关系及对SIS的诊断价值。结果显示SIS组Constant评分、最短肩肱间距低于对照组,肩峰指数、肩锁关节骨赘高度高于对照组,且SIS组治疗有效患者肩峰指数、肩锁关节骨赘高度低于无效患者,最短肩肱间距高于无效患者(P<0.05);SIS患者肩峰指数、肩锁关节骨赘高度与Constant评分呈负相关,而最短肩肱间距与其呈正相关(P<0.05);各MRI相关定量参数均为SIS发病的重要影响因素(P<0.05)。应用各MRI相关定量参数联合诊断SIS特异度为87.50%,敏感度为80.36%。由此可知MRI相关定量参数对SIS诊断价值较高,且与肩关节功能和治疗效果有关。     

稳态“冷源”法对冰的导热系数测量系统研究

本文基于稳态“冷源”法设计了一种实现在常温环境下测量冰的导热系数的实验装置.结果表明,该系统对冰的导热系数测量准确,重复性好,操作简单,成功率高,应用前景广阔.该研究也是大学物理实验教学中“物体导热系数的测定”实验的拓展,对促进实验教学以及冰这一物质的研究具有重要意义.     

三个巢式磷碳硼烷镍配合物的合成、光谱表征和晶体结构

合成了3个巢式磷碳硼烷镍配合物[NiCl(Py){7,8-(PPh2)2-7,8-C2B9H10}].CH2Cl2(1)、[Ni{7,8-(PPh2)2-7,8-C2B9H10}2](2)、[Ni{7,8-(OPPh2)-7,8-C2B9H10}{7,8-(PPh2)-7,8-C2B9H10}](3),并通过元素分析、红外光谱、核磁共振谱以及单晶衍射等手段对其进行了表征。单晶结构分析表明,镍离子的配位环境在这3个配合物中都是稍微扭曲的平面方形,其中2个配位位置由磷碳硼烷配体的两个磷原子占据,另外2个配位位置分别由氯离子、吡啶氮原子或者氧化的磷碳硼烷配体的氧原子占据。借助于分子间的C-H…Cl氢键或者C-H.H-B双氢键作用,3个配合物都可以形成一维超分子结构。     

低价钛试剂促进下2-(2-硝基苯基)咪唑与席夫碱的反应

在低价钛试剂作用下,以四氢呋喃为溶剂,研究了2-(2-硝基苯基)咪唑与席夫碱的分子间还原偶联反应.结果发现席夫碱中C-N键的断裂优于其与硝基的偶联成环,生成了5,6-二氢化咪唑并[1,2-c]喹唑啉.     

螺烯类化合物的合成研究进展

研究发现螺烯类化合物具有优异的光学和电学性质,已经成为有机化学的研究热点之一,综述了近年来螺烯化合物的合成方法研究进展.     

Single-Photon Emission from a Single InAs Quantum Dot

Excitation power-dependent micro-photoluminescence spectra and photon-correlation measurement are used to study the optical properties and photon statistics of single InAs quantum dots. Exciton and biexciton emissions, whose photoluminescence intensities have linear and quadratic excitation power dependences, respectively, are identified. Under pulsed laser excitation, the zero time delay peak of second order correlation function corresponding to exciton emission is well suppressed, which is a clear evidence of single photon emission.     

Temperature Dependence of Photoluminescence from Single and Ensemble InAs/GaAs Quantum Dots

We investigate the temperature dependence of photoluminescence from single and ensemble InAs/GaAs quantum dots systematically. As temperature increases, the exciton emission peak for single quantum dot shows broadening and redshift. For ensemble quantum dots, however, the exciton emission peak shows narrowing and fast redshift. We use a simple steady-state rate equation model to simulate the experimental data of photoluminescence spectra. It is confirmed that carrier-phonon scattering gives the broadening of the exciton emission peak in single quantum dots while the effects of carrier thermal escape and retrapping play an important role in the narrowing and fast redshift of the exciton emission peak in ensemble quantum dots.     

Non-Thermal Photon Emission from Shell-Type Supernova Remnants

We study the non-thermal photon emission from shell-type supernova remnants （SNRs） in the frame of a two-zone model. In this model, the sites of acceleration, escape and subsequent radiation of particles （both electron and proton） are divided into acceleration and escape zones, respectively. The particle distributions consist of two components, one is produced inside the acceleration zone, the other in the escape zone. We apply this model to two young and one old shell-type SNRs and show that the observed multi-waveband photon spectra for the three SNRs can be explained well in this model and high-energy γ-rays from these SNRs may have hadronic origins.     

四氯合镉酸正十一烷铵的合成、晶体结构及低温热容

合成了四氯合镉酸正十一烷铵配合物(C₁₁H₂₃NH₃)₂CdCl₄(s)[简写: C₁₁Cd(s)]. 用X 射线单晶衍射技术、化学分析和元素分析确定其晶体结构和化学组成. 利用其晶体学数据计算出晶格能为: U_POT＝908.18 kJ·mol^-1. 利用精密自动绝热热量计测定了它在78～395 K 温区的低温热容, 结果表明, 该配合物在此温区出现两次连续的固-固相转变, 计算出两次相变的峰温、摩尔焓及摩尔熵分别为: T_trs,1＝(321.88±0.07) K, Δ_trsH_m,1＝(37.59±0.17) kJ·mol^-1, Δ_trsS_m,1＝(117.24±0.12) J·K^-1·mol^-1, T_trs,2＝(323.81±0.30) K, Δ_trsH_m,2＝(12.42±0.02) kJ·mol^-1 和Δ_trsS_m,2＝(38.36±0.09) J·K^-1·mol^-1. 用最小二乘法将实验摩尔热容对温度进行拟合, 得到热容随温度变化的多项式方程. 用此方程进行数值积分,得到此温区每隔5 K 的舒平热容值和相对于298.15 K 时的热力学函数值.     

巯基吡啶配基液相色谱固定相的制备及其对质粒的快速纯化

在基因治疗中,质粒是一种常用的非病毒型载体。由于目前市场上对质粒的需求量很大,因此有必要开发大规模的质粒制备技术。该文以双孔型流通色谱介质为基质,以巯基吡啶为配基,制得了液相色谱固定相,并考察了其对质粒DNA的纯化效果,分析了分离机理。结果表明:该分离介质对质粒的纯化是基于疏水作用;当上样量为10 mL (质粒质量浓度为0.30 mg/mL)、流速高达4 mL/min时,质粒仍然能以100%的收率实现纯化,其纯度为100%。该色谱介质对RNA的柱容量高达2.2 mg/mL。