Synthesis and crystal structure of a Ni(II)complex with 1,7-diaminoethyl-4,10-dimethyl-1,4,7,10-tetraazacyclododecane

The crystal structure of a. Ni(II) complex with 1,7-diaminoethyl-4,10-dimethyl-1,4,7,10-tetraazacyclododecane has been determined by X-ray diffraction method. Crystal data for NiC14H38Br2N6O: monoclinic, space group P21/n, a=0.8848(3), b=1.4656(3), c=1.5828(3) nm, β=90.47(3)°, V=2.0525 nm3, Z=4. The two pendant primary amino groups are located in cis positions in the complex, "their nitrogen atoms and the four nitrogen donors of the foled tetraaza-macrocycle coordinate Ni(II) ion, forming a distorted octahedral geometry.     

Syntheses and Crystal Structures of Chiral BINOL Derivatives and Their Applications in Enantioselective Lewis Acid Catalyzed Addition of Diethylzinc to Aldehydes

Two novel chiral BINOL derivatives with bis(benzylamine) groups at the 3,3- positions have been synthesized through the condensation reaction between 2,2'-bis(methoxy- methyleneoxy)-1,1'-binaphthyl-3,3'-dicarboxylic acid and benzylamine or N-phenyl benzylamine in the presence of triethylamine. Suitable single crystal of (R)-N,N'-dibenzyl-2,2'-dihydroxy-1, 1'-binaphthly-3,3'-diformamide (R)-3 for X-ray diffraction was obtained by recrystallization at room temperature from the mixture solvents. Crystallographic data of (R)-3: C40H36N2O6, Mr = 640.71, monoclinic, space group P21, a = 6.746(3), b = 21.883(9), c = 11.723(5) , β = 104.605(7)°, Z = 2, V = 1674.7(12) 3, Dc = 1.271 g/cm3, F(000) = 676, R = 0.0729, wR = 0.1687 and μ(MoKα) = 0.086 mm-1. Two chiral BINOL ligands were found to be effective in the enantioselective addition of diethylzinc to aldehydes and much different enantioselectivity was observed both in the presence and absence of Ti(OiPr)4. In the former case, (R)-3 showed moderate enantioselectivity, which was lower than that of (R)-BINOL's; and in the latter case, (R)-4 gave the highest enan- tioselectivity up to 93.3% ee.*     

咪唑盐聚合物与环氧树脂复合的研究

用红外光谱和X射线光电子能谱研究了咪唑与金属铜的反应,证明反应生成了咪唑铜盐聚合物,此聚合物能在铜表面形成极薄的保护层,并能引发环氧树脂开环聚合固化,用DSC对咪唑铜盐聚合物引发苯基缩水甘油醚的动力学进行了初步研究,同时测定了界面复合的剪切强度。     

国产掺镱双包层光纤的激光特性

 采用MCVD方法研发了掺镱双包层光纤，并对其结构特性、荧光特性和激光特性进行了测试和研究。其D形内包层尺寸为400/450μm，数值孔径为0.36,纤芯直径约为16μm，数值孔径约为0.18。荧光谱线的范围为1 000~1 140 nm，1 030 nm处的峰宽大于50 nm。采用大功率激光二极管单端泵浦6 m长的双包层光纤，在泵浦入纤功率为61 W时， 获得了32 W的激光输出，斜率效率为64%。该光纤在高功率处未发现饱和现象，通过优化光纤参数与泵浦方式还可以提高转化效率和输出功率。实验表明该光纤可以取代进口光纤用作高功率激光器件。     

气压对VHF-PECVD制备的μc-Si∶H薄膜特性影响的研究

本文主要研究了用VHF PECVD方法制备的不同工作气压的微晶硅薄膜样品。结果表明 :沉积速率随反应气压的增大而逐渐增大 ;光敏性 (光电导 /暗电导 )和激活能测试结果给出了相同的变化规律 ;傅立叶红外测试、X射线衍射和室温微区喇曼谱的结果都表明了样品的晶化特性 ;通过工艺的具体优化得出了器件级的微晶硅材料     

半参数回归模型中误差方差估计的Berry-Esseen界

综合最小二乘法和局部线性光滑法给出了半参数回归模型中误差方差的估计量σ_n~2,在适当的条件下,证明了σ_n~2的Berry-Esseen界可达到O(n-1／2).     

计价单位变换在公司可转债中的应用

可转换债券是一种既含债券性质又含期权性质的金融衍生产品,其内含的将债券转换成股票的期权不是一般的标准期权,而是一种期权的买方有权将一个资产转化为另一个资产的奇异期权——交换期权.以前对可转换债券的定价研究,很少对其内含期权的这一特点加以重视.本文从对交换期权的定价角度入手,利用转换计价单位的方法,推导可转换债券的定价.     

在线流动注射N1923萃淋树脂预富集火焰原子吸收法测定痕量金

研究了富集酸度、进样体积、洗脱流速、富集时间、洗脱液的浓度和酸度、共存离子的影响 ,建立了N1 92 3萃淋树脂富集在线流动注射火焰原子吸收法测定痕量金的新方法。富集倍率为 32倍 ,检测限为 1 μg·L- 1 。用于电镀金废液的在线测定 ,方法灵敏度高、操纵简便、结果较好。     

电子温度对HL－1托卡马克低杂波电流驱动的影响

本文利用较简单的计算模型计算低杂波沿射线轨迹的能量沉积和电流分布。结果表明，当等离子体中心电于温度不太高（Ｔｅ＜１ｋｅＶ）时，边缘冷等离子体区电子－离子碰撞吸收的能量占相当大的比例，因此电流驱动效率较低。提高中心和边缘电子温度，将较大幅度地增加低杂波电流驱动效率，从而可解释为什么在小托卡马克中低杂波电流驱动效率比在大、中型托卡马克中小得多。