丙酮肟与某些芳烃相互作用的1H核磁共振研究

~1H NMR spectra of acetoxime have been measured as a function of the mole fraction of certain aromatic hydrocarbons in mixed solvent of CCl_4 and benzene or toluene. It has been found that the chemical shifts of the two methyl groups in acetoxime and of benzene or toluene move upfield gradually in the mixed solvent as the mole fraction of aromatic component increases. The moving rate of the resonance absorption line of the two methyl groups in acetoxime are different. The △δ of β-CH_3 is larger than that of α-CH_3. The absorption line of the two methyl groups is a singlet in CCl_4 and splits to a doublet when the concentration of benzene or toluene in the solvent is higher than 30% (mole/mole). The experimental results also show that the extent of upfield shifts of either the methyl groups in acetoxime or the aromatic hydrogens are reduced when a hydrogen of benzene is substituted by methyl group. All of the chemical shifts can be correlated with a linear equation as δ=A+Bx, Where, x is the mole fraction of benzene or toluene in the mixed solvent. The correlation coefficients R are approximately equal to -1.     

Synthesis and Thermal Decomposition Kinetics of the Complex of Samarium p-Methylbenzoate with 1 ,10-Phenanthroline

The complex [Sm（p-MBA）3phen]2 （p-MBA, p-methylbenzoate; phen, 1,10-phenanthroline） was prepared and characterized by elemental analysis, IR and UV spectra. The thermal decomposition process of [Sm（pMBA）3phen]2 was studied under a static air atmosphere by TG-DTG and IR techniques. Thermal decomposition kinetics was investigated employing a newly proposed method, together with the integral isoconversional non-finear method. Meanwhile, the thermodynamic parameters （AH#, △G# and AS#） were also calculated. The lifetime equation at mass-loss of 10% was deduced as In r=-24.7825＋ 18070.43/T by isothermal thermogravimetric analysis.     

基于GaSb/CdS薄膜热光伏电池的器件设计

基于GaSb薄膜热光伏器件是降低热光伏系统成本的有效途径之一, 本文主要针对GaSb/CdS薄膜热光伏器件结构进行理论分析. 采用AFORS-HET软件进行模拟仿真, 分析GaSb和CdS两种材料各自的缺陷态密度、界面态对电池性能的影响. 根据软件模拟可以得知, 吸收层GaSb的缺陷态密度以及GaSb与CdS之间的界面态密度是影响电池性能的重要因素. 当GaSb缺陷态增加时, 主要影响电池的填充因子, 电池效率明显下降. 而作为窗口层的CdS缺陷态密度对电池性能影响不明显, 当CdS缺陷态密度上升4个数量级时, 电池效率仅下降0.11%.     

宝石能谱CT对胃癌区域淋巴结转移的诊断价值

目的 研究宝石能谱CT（gemstone spectral CT,GSCT）对胃癌区域淋巴结转移的诊断价值。方法 回顾分析52例胃镜下组织学活检证实为胃癌并行GSCT（GSCT 组,24 例）或双源CT（dual source CT,DSCT）（DSCT 组,28 例）的患者,两组除常规CT增强检查外,GSCT在动脉期应用能谱成像GSI（gemstone spectral imaging）软件,获得区域转移淋巴结与胃癌病变的能谱衰减曲线,对比分析两组CT结果与术后病理结果符合率及GSCT 对转移淋巴结评估的准确性。结果 通过计算淋巴结大小、CT 值差值及短长径比值的方法,GSCT 组评估淋巴结转移与病理符合率高于DSCT 组（P＜0.05）;胃癌及转移淋巴结能谱分析结果无统计学差异（P≥0.05）。结论 GSCT 检查胃癌区域淋巴结转移与病理结果的一致性高于DSCT;GSCT可对胃癌术前转移淋巴结进行详细判断,并对术前评估提供了理论依据和技术支持,具有重要的临床应用价值。     

还课教学模式在试卷分析教学中的初探

一、"还课"概述还课起源于建构主义教学理论在实际教学中的尝试,是近年来主动学习、建构学习的一种课堂教学模式.一般认为,还课教学模式是建构理论在教学中的一种延伸,其利用教师的引导、学生的学习,将课堂教学还给学生,但与建构理论有所区分的是,还课教学需要教师合理的教学设计和引导,而建构理论纯粹要求学生做自主学习和探索,这对于我们现在所处的学情而言是比较难以实现的.还课研究尚处于起步阶段,从近年来的一些还课探索来看,很多教师在还课研究和尝试中并未领会到还课     

具有模糊目标的多目标双矩阵对策集结与求解

针对不确定性多冲突环境,建立了多个具有模糊目标的多目标双矩阵对策的综合集结模型.在假定局中人各模糊目标的隶属函数为线性函数的情形下,基于总体模糊目标的可达度,给出了纳什均衡解的定义,并应用粒子群优化算法对集结模型求解.最后,给出一个军事例子说明了模型的实用有效性和粒子群优化算法求解的高效性.     

热重法测定碱性紫11:1的热稳定性及使用寿命

1 引言碱性紫11:1是一种广泛使用的染料,它应用于皮革、腈伦、革制品等染色.染色时,其使用寿命与操作温度密切相关,较高温度下使用,其寿命较短,乃至不宜使用.为了搞清上述关系,我们用TG法研究了碱性紫11:1的热稳定性及使用寿命.     

薄层色谱—质谱联用技术及其进展

概述了薄层色谱同质谱的联用（TLC-MS）技术及其进展，着重介绍了TLC-MS联用技术中的多种接口及已经开始广泛使用的几种较先进的电离方法。     

原子荧光光谱法测定多金属矿标准样品中的砷、汞、铋

采取减少试样反应量及必要的分离手段，以原子荧光光谱法测定基体成分复杂、待测元素含量差异较大的多金属矿标标准样品中的砷、汞、铋，砷、汞、铋的检出限分别为0.2、0.01、1.3ng/mL，测定结果的相对标准偏差分别为1.88%-4.04%、2.1%-5.8%、1.1%-8.9%，线性相关系数均大于0.9970。标准样品的测定结果与推荐值基本吻合。该方法具有简单、快速、准确、精密度好等优点。     

Synthesis and Structure of [Er4（μ3—OH）4（Hpro）4（Pro）2（H2O）7]（ClO4）6.7H2O

1 INTRODUCTION The design and synthesis of polynuclear com- plexes have attracted chemists?attention in the contemporary chemistry, since their clusters maybe lead to novel materials with magnetic, optical, electronic and catalytic properties of the constituent metals[1～3]. It is also prevalently interesting to synthesize high-nuclearity metal complexes for their nanoscopic dimensions[3, 4]. Spectroscopic properties of the lanthanides are widely used in the study of biological systems. …