氦,氢,氮空心阴极放电的真空紫外辐射特性

介绍了一种水冷、陶瓷封接结构的空心阴极放电装置.研究了He、H_2、N_2在120nm～20Onm范围内该装置的真空紫外辐射特性,获得了100～600mA电流范围内的辐射强度与放电电流的关系,以及充气气压变化对它的影响.实验表明:在实验条件下,主要发射谱线为氮的原子线和氦的离子线;辐射谱线强度在0.03～0.72mW·cm~(-2);气压改变时,N_2、H_2辐射强度有一极大值,而He的离子线辐射强度则出现二个极大;在He/H_2混合气体放电时,随着He的加入,氢分子带光谱有明显下降.     

Simulation of the Field Emission Arrays with Parallel Wedge Emitter, Gates and Co-Planar Lens

Using the particle-in-cell (PIC) simulation code MAGIC, the wedge emitter, parallel gate and anode with and without co-planar lens have been simulated. The electron beam streamlines and the X-V_x phase space have been evaluated, which show that the co-planar lens focuses the electron. Simulation results are presented for a single FEA's cell with the anode biased at 500V and spaced 100m from the cathode, which indicated that the electron beam width at anode is about 60.2m for without lens FEAs, after add the lens with –70V, the electron beam width will be decrease to 8.1m, meanwhile the maximum transverse velocity will decrease from ±1×10⁶m/s to ±1.46×10⁵m/s.     

Study on microwave excited by virtual cathode oscillation in cavity

Microwave excited by virtual cathode (VC) oscillation in a cylindrical cavity is analyzed. The VC is regarded as a oscillating charged disk. By the means of model expansion method, the relation between microwave frequency and VC oscillation in a specific cylindrical cavity is obtained. The expressions of mode expansion coefficients are derived. The results show that at longer cavity length, the microwave excited is more pure, this is in good agreement with experiment results. Analysis confirms that the closer is the characteristic freuency of a mode to the oscillating frequency of VC, the larger is the mode expansion coefficient.     

Study of a Waveguide CO_2 Laser with Two Parallel Tubes

ＳｔｕｄｙｏｆａＷａｖｅｇｕｉｄｅＣＯ２ＬａｓｅｒｗｉｔｈＴｗｏＰａｒａｌｅｌＴｕｂｅｓＨＵＡＮＧＹｕａｎｇｑｉｎｇ（Ｄｅｐｔ．ｏｆＳｃｉ．Ｉｎｓｔｒ．ａｎｄＰｒｅｃｉｓｉｏｎＭｅｃｈ．ｏｆＸｉａｍｅｎＵｎｉｖ．，Ｘｉａｍｅｎ，３６１００５，Ｃｈｉｎ...     

新型锂离子电池正极材料LiMPO_4(M=Fe,Mn)的谱学和电化学研究

采用固相反应与液相反应,合成了新型锂离子电池正极材料LiMPO4(M=Fe,Mn)。粉末X光衍射表明材料均为纯相。对材料的显微拉曼光谱和红外光谱进行了研究和指认。循环伏安研究表明,含锂磷酸盐是一类有潜力的锂离子电池正极材料。     

非晶金刚石膜的性能及其应用

非品金刚石薄膜具有超高硬度等一系列优异的特殊性能,为工程界孜孜追求的材料表面镀膜。用百纳科技公司研发制造的过滤阴极真空电弧离子镀膜机镀制的非晶金刚石薄膜,SP^3金刚石结构量≥80％,硬度高,膜／基结合力高,摩擦系数小,耐磨损,耐腐蚀,透光率高,在电子,机械,光学,生物医学上有广泛应用前景。我们已在视窗玻璃,丝锥,模具,硬质合金刀头等产品上成功应用。     

阴极还原处理对多孔硅发光性能的影响

对经过阴极还原处理后的多孔硅样片进行了光致发光测试和稳定性测试.实验结果表明这种处理能明显改善多孔硅的发光稳定性,使其表面结构更加稳定.利用原子力显微镜对不同还原时间的多孔硅微结构及形貌进行了比较,在一定范围内随着还原时间的增长多孔硅表面粗糙度增大,PL谱增强.     

阴极材料Li1.2Cr0.4Mn0.4O2的制备及其电化学性能

采用溶胶凝胶法制备层状富锂Li1.2Cr0.4Mn0.4O2阴极材料．研究煅烧温度对阴极材料的结构，及电化学性能的影响．利用X-射线衍射(XRD)、扫描电镜(SEM)、X-射线光电子能谱(XPS)等方法对阴极材料的晶体结构、充放电过程中价态的变化、表观形貌、粒径大小等进行分析．结果表明850℃时煅烧后的阴极材料层状结构明显，电化学性能优良．以小放电速度进行恒流(10mA／g)充放电循环，首次放电比容量可以达到280mAh／g，经过40次循环后仍可以达到190mAh／g．研究发现在整个充放电过程中Mn始终保持 4价态，部分Cr作为活性离子价态在 6和 3之间可逆变化．Li1.2Cr0.4Mn0.4O2经过镀银后以大放电速度进行恒流(80mA／g)放电可以达到100mAh／g的比容量．     

微脉冲电子枪的初步实验研究

给出了微脉冲电子枪的模拟计算及其初步实验结果. 该电子枪采用铜铝镁合金作为冷阴极材料, 在以磁控管作为微波功率源的出束实验中得到了100mA/cm²的电流密度.实验结果与次级电子倍增解析计算和SEEG程序的模拟计算结果基本符合, 初步验证了微脉冲电子枪的基本原理, 为今后实验中得到更大的电流密度打下了基础.     

A 3D fibrous cathode with high interconnectivity for solid oxide fuel cells

A three-dimensional (3D) fibrous cathode of solid oxide fuel cell was fabricated by using eggshell membranes (ESMs) as the template. This cathode possesses high porosity and interconnectivity, and low polarization resistance. A single fuel cell with the 3D fibrous Sm_0.5Sr_0.5CoO₃/Ce_0.8Sm_0.2O_1.9 cathode shows significantly improved performances at low operating temperatures (500–600 °C) as compared with the cell prepared with the ESM-templated cluster cathode in our previous study.