MoO3氧化物掺杂改善LiFePO4 / 乙炔黑电化学性能研究

采用MoO₃氧化物前驱物对磷酸铁锂(LiFePO₄)进行少量的掺杂，并用XRD、SEM、CV及恒流充放电测试对产物进行了研究。研究表明，少量的掺杂并未影响到LiFePO₄的晶体结构，但却能够在一定程度上改善LiFePO₄的电化学性能。其中650 ℃焙烧的1% Mo掺杂的LiFePO₄材料性能较好，该材料在以0.2 C的倍率充放电时，充放电曲线具有平稳的电压平台和较大的充放电容量，首次放电容量能达到     

Li[Ni1/3Mn1/3Co1/3]O2掺杂Mo研究

采用高温固相合成法制备了Li[Ni_(1－x)/3Mn_(1－x)/3Co_(1－x)/3Mo_x]O₂ (x＝0, 0.005, 0.01, 0.02). 对它们进行了XRD, SEM, 循环伏安及充放电容量测试, 结果发现, 掺杂x＝0.01 Mo的样品具有较高的嵌锂容量和良好的循环稳定性, 在20 mA/g放电电流密度和2.3～4.6 V的电压范围内具有211.6 mAh/g的首次放电比容量, 循环50周后放电比容量仍能达到185.9 mAh/g, 容量损失为12.1%.     

Solid state reactions of nitrogenous heterocyclic compounds (Ⅱ)——Solid state reactions of indole with carbonyl compounds

Solid state Michael addition reaction of indole with α,β-unsaturaled carbonyl compounds was carried out,by which a series of compounds containing three different heterocyclic groups binding to one carbon atom were obtained.In the presence of Lewis acid,indole could undergo the solid state condensation reaction with aromatic ketones and aldehydes or quinones.The solid state reaction showed higher selectivity and yield than solution reaction The structures of products were identified by IR,1H NMR,MS,elemental analysis and X-ray crystal analysis.The reaction mechanism was also proposed.     

Synthesis and Crystal Structure of 2-(Diphenylphosphine oxide)-3-(diphenylphosphine oxide ethynyl) spiro [bicyclo[2.2.1]hepta-2,5-diene-7,1''''-cyclopropane]

1 INTRODUCTION Organic phosphine compounds always attract great interest for their unique properties and extensive uses in biochemistry, pesticide chemistry and synthetic organic chemistry. In the last two decades, much attention has been paid to phosphorus-containing olefin and acetylenic compounds for their applications in transition metal chemistry, asymmetric catalysis and photorearrang- ement [1~7 ]. Previously, we have reported the crystal structure of a novel host compound which …     

新型膦酰基取代的脂环化合物的合成研究及手性拆分

研究了二(二苯基氧化膦)乙炔同取代环戊二烯的Diels-Alder反应，合成了四个新型有机膦脂环化合物，并用^1H NMR，MS和元素分析确定了它们的结构，同时以(±)-二苯甲酰酒石酸为拆分剂，对外消旋9,10-二氢-9,10-亚乙烯基-2,3-苯并蒽-11,12-二(二苯基氧化膦)进行了拆分，得到了两个有光学活性的产物。     

煅烧温度对锂离子正极材料Li[Ni0.475 Mn0.475 Co0.05]O2结构和电化学性能的影响

应用高温固相合成法制备L i[N i0.475Mn0.475Co0.05]O2.XRD,SEM,循环伏安及充放电容量测试表明,在800℃下煅烧合成的样品具有较高的嵌锂容量和良好的循环稳定性,如在20 mA/g和2.3~4.6 V的电压范围内,其首次放电比容量为178.8 mAh/g,循环30周后放电比容量仍能达到150.2 mAh/g,容量损失16.0%.     

微波固相合成苯并[a]吩噁嗪衍生物

首次在固相条件下微波辐射N,N-二烷基-4-亚硝基苯胺盐酸盐和2-萘酚衍生物快速合成苯并[a]吩嗪衍生物,得到苯并[a]吩嗪离子氯化物3a-3f,且收率较高.此外,N,N-二甲基-4-亚硝基苯胺盐酸盐和1,3-二羟基-2-萘甲酸乙酯的混合物在微波辐射下合成了一个新的激光染料9-二甲氨基-6-乙氧羰基-5H-苯并[a]的吩 嗪-5-酮4.     

固态有机反应新进展

总结了一些典型的固态有机反应。由于固态反应的特性，多数固态有机反应表现出较溶液中更高的反应效率和更好的选择性，在某些情况下，利用光活性主体与反应物形成包结物，可实现对映选择性的不对称固态合成。     

合成半导体胶体纳米晶的新方法

半导体纳米晶由于其独特的光学和电学性质在光学器件、医疗诊断、激光等方面有了越来越重要的应用.本文介绍了胶体半导体纳米晶合成技术的一些最新进展。     

Synthesis and photoreaction of polymethylenediamine bis(4-methyl-7-coumarinyl)oxyacetic amides

A series of polymethylenediamine bis(4-methyl-7-coumarinyl)oxyacetic amides have been synthesized and their intramolecular photochemical cyclodimerizations have been investigated It was found that only syn-HT configuration products were obtained when these bisamides were directly irradiated in dimethyl sulfoxide solution and the yields of the products decreased with the intrease of the chain length.The structures of long chain amides and their intramolecular photoryrlizatum products were determined by IR,MS,1H NMR and elemental analysis.