球磨方式对锂离子正极材料LiFePO4性能的影响

采用高温固相合成法制备橄榄石型的LiFePO₄正极材料，在合成过程中分别采用湿法球磨和干法球磨两种球磨方式。用X-射线衍射，扫描电镜，激光粒度测试等对合成材料进行表征，并对以LiFePO₄为正极的电池进行电化学性能测试。结果表明，相对于干法球磨，湿法球磨制备的LiFePO₄样品具有更好的电化学性能，0.2C放电的首次放电比容量为134.9 mAh·g^-1，并有优良的大电流放电性能及循环性能。这主要是因为采用湿法球磨制备的LiFePO₄材料物相较纯、粒径均匀，与导电添加剂的接触更加紧密，从而提高了LiFePO₄材料电化学性能。     

四-α-(2-甲基-8-喹啉氧基)酞菁金属配合物的合成、表征及光敏活性研究

利用DBU催化法合成得到4种两亲性的四-α-(2-甲基-8-喹啉氧基)酞菁金属配合物[金属＝Co(II), Ni(II), Cu(II), Zn(II)], 同时分别进行了元素分析、质谱、UV-Vis、IR光谱表征. 测定了它们在670 nm光激发下产生单线态氧的速率及光动力氧化氨基酸底物的速率常数, 探讨了它们光敏活性的构效关系.     

Hydrothermal Synthesis and Crystal Structure of a Heterometallic Cu/Cd Complex with H2dipic （Pyridine-2,6-dicarboxylic Acid）

1 INTRODUCTION In recent years the chemistry of coordination poly- mers has been very prosperous, affording diverse architectures[1]. The creation of these compounds with tunable properties and functions has been applied in many fields, such as molecular recogni- tion, adsorption and separation processes, catalysis, ion exchange and molecular magnet[2～4]. The advan- tage of these metal-organic compounds allows a wide choice in various parameters, including diverse electronic properties an…     

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     

瓜环与1,ω-亚烷基二吡啶二溴化合物主客体作用实体结构研究

合成并表征了六种不同碳链长度的1,ω-亚烷基二吡啶二溴化合物(客体),利用1HNMR技术、紫外吸收光谱和电化学方法考察了这些客体与六、七、八元瓜环(主体)相互作用,以及形成的主客体包结配合物的结构特征.研究结果表明,六种客体均能与六、七、八元瓜环形成主客体配合物,但作用模式随碳链的长度、瓜环的大小而各不相同.