Modeling of axis-symmetric steam plasma flow in a non-transferred torch

This paper discusses the numerical modeling of steam plasma in a DC non-transferred torch equipped with well-type cathode, where the non-trivial azimuthal velocity component and turbulent effect are both taken into account. In order to investigate the complicated flow characteristics of thermal plasma due to the interaction between steam and electric arc, the flow filed inside the plasma torch is modeled by the magnetic–hydrodynamic (MHD) equations. The governing equations are then solved numerically using a non-staggered finite volume discretization based on Cartesian grid system. The anode location and maximum current density at cathode are fixed by the corresponding experimental measurement at a given flow rate. The predicted result suggests that the steam plasma can be accelerated to a mean velocity of 1500 m/s at torch outlet with the mass flow rate of 5 g/s and the system current of 180 A. A strong vortex flow structure is found inside the torch due to the introduction of azimuthal velocity at the gas inlet, which should help to stabilize the rotating arc during the torch operation.     

CRT and LCD monitor and process materials evaluated for environmental improvement

Decision rules have been developed and applied to the bills of materials of a color cathode‐ray tube (CRT) and a liquid‐crystal‐display (LCD) desktop monitor to determine which product and process materials will be evaluated in an environmental life‐cycle assessment. Materials of significant mass, of technological importance, and of potential environmental impact are targeted. The list of materials identified are those for which life‐cycle inventory data will be obtained for the materials extraction and materials processing life‐cycle stages of a CRT and an LCD. Additionally, materials identified will also be used to represent life‐cycle impact in terms of resource consumption, as well as surrogates for occupational health impacts.     

一种新型的霓虹灯扫描控制器

介绍一种用8031(8051)串口,联级新型的共阴极驱动芯片— —MAX7219霓虹灯扫描控制器。着重论述了该芯片的硬件特点、使用方法及软件编制方法, 给出了用该芯片驱动多点霓虹灯变压器的实例。     

Synthesis and properties of the modification of micro-crystal LiMn2−x Al x O4 cathode material for Li-Ion batteries

The micro-single crystal material spinel LiMn2-xAlxO4 was prepared by a sol-gel procedure and modified by alumina; the electrochemical measurements show that the performances and characteristics of modified LiMn2-xAlxO4 electrode material are better than those of LiMn2O4. Hence, the modified LiMn2-xAlxO4 is a good cathode material for lithium batteries. This can be explained that the size of the modified particle is larger than that of unmodified material, so electrons can be easily transported between the particles.     

Synthesis and characterization of Li1.05Co0.3Ni0.35Mn0.3M0.05O2 (M=Ge,Sn)cathode materials for lithium ion battery

In order to improve the electrochemical performance and thermal stability of Li_1.05Co_1/3Ni_1/3Mn_1/3O₂ materials,Li_1.05Co_0.3Ni_0.35Mn_0.3M_0.05O₂（M=Ge,Sn）cathode materials were synthesized via co-precipitation method.The structure,electrochemical performance and thermal stability were characterized by X-ray diffraction（XRD）,charge/discharge cycling,cyclic voltammetry（CV）,electrochemical impedance spectroscopy（EIS）and differential scanning calorimetry（DSC）.ESEM showed that Sn-doped and Ge-doped slightly increased the size of grains.XRD and CV showed that Sn-doped and Ge-doped powders were homogeneous and had the better layered structure than the bare one.Sn-doped and Ge-doped improved high rate discharge capacity and cycle-life performance.The reason of the better cycling performance of the doped one was the increasing of lithium-ion diffusion rate and charge transfer rate.Sn-doped and Ge-doped also improved the mateials thermal stability.     

Fe掺杂LSCCF对中低温固体氧化物燃料电池ITSOFC短期输出性能的影响

柠檬酸盐法制备La0.7Sr0.15Ca0.15Co1-xFexO3-δ(x=0.2、0.4、0.6、0.8)阴极材料。该前驱体在900℃处理2h后,XRD证实已经形成完整的钙钛矿结构衍射峰。随Fe掺杂量增加,XRD谱图衍射峰的位置向小角度发生偏移,粉体的晶粒尺寸逐渐变大。SEM观察La0.7Sr0.15Ca0.15Co1-xFexO3-δ粉体其表面活性较高并出现了一定的团聚现象,颗粒尺寸约为5μm。以La0.7Sr0.15Ca0.15Co1-xFexO3-δ为阴极,在氢气/空气中研究了模压法制备的单电池性能,Fe掺杂量对开路电压的高低不起决定性作用,而最高功率密度随Fe掺杂量增加而降低,在650℃最高功率密度由x=0.2时的351.7mW/cm2降为x=0.8时的231.1mW/cm2。     

软X射线波段透射光栅检测系统

目前,透射光栅被广泛地应用于软X射线波段光谱测量当中。但由于在软X射线波段几乎所有材料都有非常明显的吸收,因此利用传统方法很难在该波段对透射光栅进行检测。为了检测透射光栅在软X射线波段的光谱分辨本领,我们基于掠入射理论,采用凹面反射光栅单色仪配X射线CCD相机组成一套软X射线波段透射光栅检测装置。首先利用He空心阴极光源的30.38nm、53.70nm和58.43nm三条线谱对透射光栅检测系统进行波长标定。然后更换激光等离子体光源,测量并得到了金自支撑式透射光栅在6.67nm和9.10nm两个波长位置上一级衍射位置和一级衍射光谱线宽度,利用半宽度法计算并得出在以上两个波长位置时被测透射光栅一级谱所能分辨的最小波长差为2.38nm和2.05nm。实验结果表明该投射光栅检测系统完全可以应用于软X射线波段透射光栅检测工作当中。     

硝酸盐质量浓度对微生物燃料电池产电及反硝化的影响

目的研究在不同的硝酸盐质量浓度下,MFC的产电、阴极反硝化情况及阳极COD和氨氮的处理情况．实现产电与阴极反硝化的同时进行．方法阳极以实验生活污水为处理对象,阴极以自配具有一定质量浓度的硝酸盐溶液为处理对象,改变阴极的硝酸盐质量浓度,阳极为间歇厌氧运行模式,阴极为间歇缺氧运行模式．结果 当硝酸盐质量浓度由20-200mg／L逐渐增加时,随着初始硝酸盐质量浓度的增加,亚硝酸盐的积累逐渐增加,最高可达65mg／L,硝酸盐相对去除率几乎没有变化,而硝酸盐的绝对去除率则逐渐减小．硝酸盐质量浓度从20～120mg／L变化时对微生物燃料电池的产电效果基本没有影响,当硝酸盐质量浓度增加到160mg／L时,平均输出电压和最高功率密度明显增加,而当硝酸盐质量浓度增加到200mg／L时,平均输出电压和最高功率密度又明显减少．结论阴极硝酸盐质量浓度为160mg／L时,MFC阳极COD的去除率最高,产电效果最好．     

Performance of Sewage Sludge Treatment and Electricity Generation by Different Configuration Microbial Fuel Cells

This paper compared the degradation efficiency of sludge organic matters and electric-production by two typical microbial fuel cells——dual-chamber microbial fuel cell(DMFC)and single chamber air cathode microbial fuel cell(SAMFC),and the variations of sludge protein,polysaccharide and ammonia nitrogen within the systems were also investigated.The results showed that the concentration of sludge soluble chemical oxygen demand,protein and carbohydrate of DMFC are higher than these of SAMFC during the systems operation,while DMFC can achieve a better ammonia nitrogen removal than SAMFC.Under the same operation condition,the stable voltage output of DMFC and SAMFC is 0.61 V and 0.37 V;the maximum power density of DMFC and SAMFC is 2.79 W/m3and 1.25 W/m3;TCOD removal efficiency of DMFC and SAMFC is 34.14%and 28.63%for 12 d,respectively.Meanwhile,DMFC has a higher coulomb efficiency than SAMFC,but both are less than5%.The results showed that DMFC present a better performance on sludge degradation and electric-production.     

八面河油田油润滑防偏磨工艺研究与现场应用

八面河油田目前主要是采用传统的油井防偏磨工艺,而在高含水的井液中易导致杆、管偏磨机率增加,随着含水率的上升,偏磨失效井次也相应上升。所以,应在传统的油井防偏磨工艺的基础上,结合实际情况应用新技术。而空心杆油润滑防偏磨工艺的技术可以对油井偏磨防治起到一定效果。