表面终端金刚石场效应晶体管的研究进展

金刚石因具有极高热导率、5.5 eV宽带隙、极高击穿电场、高固有载流子迁移率和低介电常数等优异性能,在高功率、高频、高温及低功率损耗电子器件领域中成为有力的竞争者。然而,研究人员对金刚石半导体掺杂技术进行了几十年的探索和优化,却仍然无法满足当前电子器件的应用需求。最近,随着H终端金刚石表面二维空穴气的发现,研究重心逐渐转向优化H终端金刚石的导电特性及制备场效应晶体管(Field Effect Transistor, FET)。综述了H终端金刚石研究的发展历程,从栅层材料选择、表面终端处理、金刚石掺杂和FET结构优化出发,归纳了提升表面终端金刚石FET器件性能的方法,并对表面终端金刚石FET的发展前景进行了总结和展望。     

涡轮式压缩机引线铜管失效原因分析

针对技术成熟度较高的涡轮式压缩机泄漏失效问题,采用金相显微镜、扫描电镜、能谱仪、维氏显微硬度仪等技术手段,对泄漏部位进行分析．结果表明：泄漏部位为压缩机引线铜管,铜管泄漏失效机制为疲劳失效;泄漏失效原因为压缩机引线铜管材质硬度过高,不适宜再次机械加工,并且机械加工工艺与铜管硬度不相适应．      

原子层沉积薄膜的表征方法进展

原子层沉积（ALD）是一种新兴的薄膜沉积技术,其最主要的优势在于可在高深宽比的结构上沉积均匀致密的纳米薄膜,因此在微电子、纳米科技等领域中具有广泛的应用．纳米厚度的ALD薄膜与传统微米厚度的薄膜材料相比,需要更精确的表征手段,因此对ALD薄膜的表征方法展开了针对性探讨．阐述了ALD薄膜的常用物性表征方法,主要从薄膜厚度、成分、结晶性及形貌等方面展开探讨,同时展望了其未来发展的方向．      

二氧化碳基TPU/淀粉共混材料性能的研究

以二氧化碳基TPU和玉米淀粉为原料,通过运用转矩流变仪制备一种综合性能优异的二氧化碳基共混材料．运用扫描电子隧道、电子拉力机、转矩流变仪和高压毛细管流变仪,分别研究了不同淀粉含量、不同温度对二氧化碳基共混材料的力学性能和流变性能的影响．结果表明：淀粉含量的增加会使得共混材料的拉伸性能和撕裂性能出现先增大后减小,当淀粉含量为30%时综合力学性能最好;温度的上升,会使得共混物的表观剪切应力和表观切黏度降低;随着淀粉含量的增加,共混物的综合加工性能逐渐下降．      

不同Mn含量及焊接电流对ER5356铝合金焊丝焊接性能的影响

为研究不同Mn含量ER5356铝合金焊丝和焊接电流对焊接焊头性能的影响,实验使用含锰量为0.05%和0.15%的ER5356铝合金焊丝,分别在110,115和125 A焊接电流下,采用TIG焊接6082铝合金．结果表明：用ER5356(0.15%的Mn)铝合金焊丝焊接得到的焊接接头的性能整体优于ER5356(0.05%的Mn)焊丝焊接得到的焊接接头,因Mn元素可以改善焊接接头的力学性能,进而提高铝合金焊接质量;随着焊接电流的增大,焊缝成形质量提高,当焊接电流为125 A时,无焊接热裂纹等宏观缺陷,焊接接头断口几乎观察不到未焊透的现象, 焊接接头匹配系数最高达到0.71.      

包装用丙烯酸酯压敏胶的制备与研究

以软丙烯酸丁酯（BA）、丙烯酸异辛酯（2-EHA）、甲基丙烯酸甲酯（MMA）、丙烯酸(AA)、丙烯酸羟乙酯（HEA）为原料,采用预乳化半连续乳液聚合法制备丙烯酸酯压敏胶,研究了软/硬单体配比和功能单体含量对压敏胶初粘性、持粘性和180 °剥离强度粘结性能的影响．实验结果表明,在软单体、硬单体、功能单体的配比为47.5∶10∶5和T^g=-30.4 ℃条件下,采用滚球斜坡停止法测定初粘力,滚球选择20号钢球,丙烯酸酯压敏胶的持粘力达到34 min,180 °剥离强度为0.26 N/mm．表明,乳液稳定好、黏度适中,涂布效果理想．      

一维磷酸锑纳米纤维的制备及其电化学性能研究

为了改善磷酸锑作为钠离子电池负极材料的电化学性能,利用静电纺丝技术巧妙地将纳米化、纳米结构设计结合在一起,在空气气氛中经热处理合成了一种一维磷酸锑纳米纤维（SbPO₄@NFs）．实验结果表明：SbPO₄@NFs作为钠离子电池负极材料,在500 mA/g电流密度下循环100圈后可逆比容量依然有300 mA·h/g;在5 A/g大电流密度下可逆比容量仍然保持有242 mA·h/g, 1 A/g电流密度下循环300圈后可逆容量为126 mA·h/g．SbPO₄@NFs复合材料的优越电化学性能表明,其具有很好的实际应用前景．      

纯钨/310不锈钢异种材料激光熔化沉积探究

采用激光熔化沉积的方法,在310S奥氏体不锈钢钢表面进行纯钨材料的增材制造．结合金相显微镜 (OM)、扫描电子显微镜 (SEM)、能谱分析 (EDS) 、X 射线衍射 (XRD) 及显微硬度仪等材料表征手段,对试样的微观组织结构、元素分布、物相组成及显微硬度进行了对比分析．结果表明：沉积层内部存在未完全熔化的钨颗粒,同时也存在完全熔化后重新凝固的富钨组织,其为金属间化合物Fe₇W₆,并且该化合物主要以枝晶形式存在;未完全熔化的钨颗粒与铁基基质呈良好的冶金结合,结合界面生成了Fe₇W₆/W的核壳结构．      

金属性MoO2纳米材料的制备及电阻的微区测量

为了研究MoO²的本征电阻率,采用化学气相沉积法（CVD）在蓝宝石衬底上制备金属性MoO²纳米材料,随后将材料转移到SiO²衬底制备成双端电阻器件,在进行电压?电流曲线测量的同时,采用开尔文探针力显微镜（KPFM）研究不同偏压下MoO²纳米材料表面电势的空间分布．结果表明：传统测量时忽略了接触电阻和热效应的影响,导致测量结果偏高;测量的MoO²的本征电阻率为6×10_-5 Ω·cm,可以媲美高质量ITO薄膜电极．所以,MoO²作为一种廉价电极材料在电子器件中具有潜在的应用前景．      

氧化物钎料连接Al2O3陶瓷的研究现状

对氧化物钎料连接Al₂O₃陶瓷的研究现状进行了阐述,介绍了目前氧化物钎料连接Al₂O₃陶瓷的一般流程和工艺方法．主要介绍了用于Al₂O₃陶瓷连接的高温氧化物钎料和低温氧化物钎料,并且分别对钎料的成分、接头组织、连接温度、接头剪切强度及组织变化趋势等进行了总结,最后指出了氧化物钎料的优势和存在的不足,旨在为氧化物钎料连接Al₂O₃陶瓷的研究重点和发展方向提供参考．      

Current situation and future trend of China rare earth luminescent material industry

<正>Rare earth luminescent material is one of the most important application sectors of rare earths.China enjoys the exceptional advantage to develop rare earth luminescent material for its abundant rare earth resources.After several decades'endeavor,China's rare earth luminescent material industry,headed by rare earth phosphor for lamp and LED and high efficient rare earth energy-saving light source,has been gradually developed into a scale industry.China has become a major production base of rare earth phosphor for lamps and rare earth     

China rare earth market review

正June 1~10,2014Rare earth market remained weak.Quoted price of rare earth products was similar to that in May.There was no sign of recovery in downstream market.The market of NdFeB magnetic materials and phosphor was depressed.Catalyst,polishing powder and ceramic industries remained inactive.Demand from downstream industry was soft.Consumers purchased on their needs.Suppliers had strong intention to sell.Prices of rare earth products     

Annual Report analysis of Chinese rare earth-related listed companies in 2013

<正>Chinese rare earth-related listed companies have published their 2013 annual reports.It can be understood from their reports that production and operation activities of Chinese rare earth-related companies were still heavily affected by macro economy and industrial policies.They basically followed the steps of national economy.In 2013,world economy recovered slowly but the economy     

Market opportunities and challenges for rare earth polishing powder

正1.Status of rare earth polishing powder Rare earth polishing powder with high content of cerium oxide began to replace iron oxide for glass polishing and became one of the key materials in glass polishing process since 1940.Compared with traditional iron oxide,rare earth polishing powder has many advantages,such as fast polishing rate,high polishing quality and long service life.It can achieve good surface quality and improve operation conditions.For example,in lens polishing,the polishing work that cerium     

Baotou Research Institute of Rare Earths developed a new RE alloy preparation technology

正Pyrometallurgy Laboratory of Baotou Research Institute of Rare Earths had independently developed a new preparation technology of rare earth alloy for NdFeB.The alloy can remarkably enhance the coercivity of NdFeB magnet but also evidently reduce the production cost of the magnet.The new master alloy was prepared in the kA pilot-scale electrolytic cell by the independent technology.The rare earth master alloy can be used as the raw material for NdFeB.Compared     

矿用防爆轴流对旋主要通风机叶片ANSYS模态分析及应用

高效节能矿用防爆对旋主要通风机的叶片是主要通风机运行的关键部件,叶片在运行时不断受到气流的作用力,从而使叶片产生振动,当叶片振动的频率与叶片的固有频率接近时,容易产生共振从而导致叶片的断裂。一旦叶片断裂时,对主要通风机的安全运行产生致命的影响,从而导致矿山、化工等企业发生重大事故,将会产生不可估量的损失。基于有限元分析软件ANSYS,对高效节能矿用防爆轴流对旋主要通风机叶片进行模态分析及产生对应的六阶模态频率,对主要通风机叶片的运行频率、固有频率及产生的共振问题进行了原理分析,并且解决了叶片频率共振的问题,从而为主要通风机叶片结构设计提供理论依据,并对主要通风机叶片的安全运行提供保障。     

2013 NdFeB export analysis

<正>China totally exported nearly 24,000 tonsof NdFeB products during 201 3,including 18,825 tons of permanent magnet,valued USD 1.34 billion at an average price of 71.4 USD/kg;3,277 tons of NdFeB magnetic powder,valued USD 1 01 million at an average price of 30.9 USD/kg;1,334 tons of strip casting ribbon,with total export value of USD 74million at an average price of 55.3 USD/kg;and 586     

Market and recycling of NiMH battery

<正>Market status and future trend of NiMH battery1.Global market of small NiMH battery Global market size of small NiMH batteries declined year on year since 2011.The trend will continue to 2018,at the rate of 5%to 10%annually.Demand for small NiMH batteries will be stable gradually.Many electrical apparatuses are powered by the built-in lithium battery today,which is the main reason for the shrunk market of small NiMH batteries.But,for some products,small NiMH     

China rare earth market review

正September 1-10,2014 Affected by the National Day holiday,rare earth transaction was stagnant and the market showed a weak steady state.As there was no good news for downstream market,some products with flat demand would likely rally slightly for some time to     

唐口煤矿深部复杂开采工作面瓦斯分源涌出规律研究

研究工作面瓦斯涌出规律对工作面瓦斯治理有重要意义。为了得到唐口煤矿深部3号煤层复杂开采条件下工作面回采时期瓦斯涌出时空演化规律,选取6304工作面作为对象,采用实测方法研究6304工作面瓦斯涌出规律。结果表明:6304工作面瓦斯涌出量为6.534 m³/min,其中煤壁占34.27%,落煤占29.62%,采空区占36.11%;沿工作面倾向由低到高,瓦斯浓度整体为上升趋势,其中1—76号架工作面瓦斯浓度小于0.20%,76—102号架瓦斯浓度上升明显,最大为0.387%;上隅角的后部采空区是工作面的瓦斯主要涌出源,上隅角1号测点瓦斯浓度0.78%,上隅角周边3号、5号、7号、8号、9号测点瓦斯浓度平均为0.643%;周期来压时,上隅角瓦斯相对平时较高。研究为针对性的瓦斯分源监控与灾害防治提供基础。