Dongmei Ban Ningsheng Xu Shaozhi Deng Jun Chen Juncong She
材料科学技术(英文)
A simple method is introduced for the preparation of large-area films of molybdenum trioxide (MoO3) microbelts. It is found that such films can be grown on indium tin oxide (ITO) glasses or silicon substrates at low temperatures by thermal evaporation deposition in air without using catalyst. Field emission measurements show that the turn-on field of the MoO3 microbelts is as low as 2.2 V/μm required to obtain a current density of 10 μA/cm2. The combination of the simplicity of the growth method and the attractive field emission performance makes it a potential low-cost technique for the preparation of large-area field emission cold cathode material.
关键词:
Field emission
,
large-area film
,
molybdenum trioxide
,
microstructures
,
synthesis
LI Gang
,
WANG Zhongguang
,
LI Guangyi(State Key Laboratory of Fatigue and Fracture for Materials
,
Institute of Metal Research
,
Chinese Academy of Sciences
,
Shenyang 110015
,
China)V.OVCHARENKO(Institute of Strength Physics and Materials Science
,
Russian Academy of Science
,
Siberian Branch
,
Tomsk
,
Russia) Manuscript received 3 May 1995
金属学报(英文版)
Self propagating high temperature synthesis(SHS) under compression was utilized to obtain an intermetallic compound Ni_3 Al by using elemental powders.The microstructure of the SHS product was observed by optical microscopy(OM) and scanning electron microscopy(SEM).The results reveal that the SHS Ni3Al is a single-phase polycrystalline alloy wilh LI2 crystal structure.Tensile tests were conducted from room temperature to 800℃ both in air and in vacuum.The results show that the SHS Ni_3Al exhibits an anomalous temperature dependence of ultimate tensile strength.The ultimate tensile strength in vacuum is much higher than that in air over the whole temperature range.Fracture surfaces are characterized by the brittle grain boundary fracture and the intergranular fracture mode can not be affected markedly by the test environment.
关键词:
:Ni_3Al
,
null
,
null
,
null
尹曾甫
,
文志潘
,
张亚雷
,
代朝猛
,
周雪飞
材料导报
doi:10.11896/j.issn.1005-023X.2016.011.022
类石墨烯的二维纳米片层状MoS2作为过渡金属硫化物材料家族的典型代表,由于其各方面独特的性能尤其是超薄的厚度和二维结构,已成为近些年材料的研究热点.独特的三明治结构使其具有良好的物理化学性质,MoS2及其复合材料在催化、传感器、润滑等方面有广阔的前景.总结了国内外MoS2的合成及其改性方法、性能和应用.针对社会发展过程中日益严重的环境污染问题,重点介绍利用其吸附和催化性能去除环境中污染物,并对其未来发展进行了展望.
关键词:
二维纳米片层
,
MoS2
,
合成
,
改性
,
吸附
,
催化
,
环境
李玉邯
,
吴强
,
康传清
,
郭海泉
,
金日哲
,
高连勋
应用化学
doi:10.11944/j.issn.1000-0518.2016.08.150401
报道了一种从卤代邻二甲苯偶联和液相氧化制备2, 3, 3', 4'-联苯四甲酸二酐(3, 4'-BPDA)的简便方法。以NiF2-PPh3(PPh3:三苯基膦)为催化体系,高效地实现了4-溴邻二甲苯格氏试剂与3-氯代邻二甲苯的交叉偶联反应,合成了2, 3, 3', 4'-四甲基联苯(3, 4'-TMDP),后者经液相氧化、高温脱水成酐制备了3, 4'-BPDA,两步总产率达到74%。这条路线与从邻苯二甲酸二甲酯或混合氯代邻苯二甲酸二甲酯制备3, 4'-BPDA相比,不涉及酯的水解及异构体的分离等过程,因此分离及环保方面具有非常明显的优势,同时合成路线更简便。
关键词:
联苯四甲酸二酐
,
合成
,
交叉偶联
,
聚酰亚胺
欧少通
,
梁新慈
,
邓家瑜
,
戴子才
,
朱梦怡
,
刘宁
合成材料老化与应用
采用反相乳液聚合法成功制备炭气凝胶微球,研究了合成条件对凝胶时间的影响。利用所得产品吸附氯化钯溶液,探讨炭气凝胶微球对Pd2+的吸附性能。结果表明,通过调控合成条件可以实现对合成过程的有效控制,炭气凝胶微球对Pd2+有优异的吸附性能,吸附率最高可达99.2%。
关键词:
炭气凝胶微球
,
合成
,
吸附
,
钯