阵列式等离子体射流特性的研究

研究了大气压下阵列式等离子体射流特性,以实现和完善大气压下大面积的低温等离子体灭菌技术.采用MAXWELL 3D软件仿真及实验的手段,研究相关因素对各种阵列式等离子体射流特性的影响.包括在单管等离子体喷射中的一些基本影响因素(电压、气体流速等)和阵列式等离子体喷射实验中所特有的一些因素(气流均匀度、电极单元间距及电极布置方式).实验在大气压氦气环境下进行,然后通过专门研发的高频高压等离子体放电电源进行了介质阻挡放电.实验结果实现了大气压下阵列式等离子体喷射,证明了通过阵列式等离子体喷射方式来实现大面积等离子体灭菌技术的可行性.除此之外还得出了各种相关因素对阵列式等离子体射流特性的具体影响,用以完善阵列式等离子体射流技术,进行更大面积的灭菌处理.     

射频辉光放电发射光谱在深度分析有效信息量方面的改进

评述了射频辉光放电发射光谱中的两种新的测量方法：调幅技术和偏置电流导电技术。这两种方法在分析薄膜试样时非常有效。应用调幅技术时，辉光放电电压以低频进行调制，在发射信号周期性变化的同时，溅射率降低。尽管随脉冲数的减少发射强度降低，但发射强度能用选频放大器选择性地进行检测，从而能获得较好的信噪比。在偏置电流导电技术中，直流偏置电流被导入由低通滤波器和负载电阻组成的辉光放电灯电路中，偏置电流将大量电子引入等离子体中，从而导致等离子体区域发射强度的增强，而同时由于偏置电流的减少而使得溅射率降低。这两种技术有利于改进辉光放电发射光谱的深度信息分析。     

高压脉冲放电处理含氰废水的影响因素探讨

许多工业废水中含有大量的氰化物,必须采取有效措施进行去除。传统去除氰化物方法运行成本高,操作复杂,针对这些问题提出了用高压毫微秒脉冲产生的非平衡等离子体处理含氰废水的方法。文中对其影响因素pH值、放电时间、空气流量、放电条件等进行了大量的试验研究;结果表明,溶液初始pH值为9．09,放电2h,放电电压46kV时,氰化物的去除率最高可达93．2％,氰化物的质量浓度可降至0．26mg／L。试验对比了放电与不放电氰化物的去除效果;结果表明,相同条件下放电后氰化物的去除率大大提高。为废水中氰化物的去除提出了一种新的方法。     

空心阴极等离子烧结功率输出特性研究

提出一种空心阴极放电等离子烧结方法,并对该种工艺过程中的加热功率特性进行了试验研究。结果表明,放电加热功率的大小与空腔尺寸、放电电压和工作气压有关。在满足空心阴极效应的条件下,空腔尺寸越小,放电电压和工作气压越高,加热功率越大。     

放电等离子体烧结W粉数值模拟

根据传热学以及电磁理论,在放电等离子体烧结的典型烧结条件下建立了电热耦合控制方程,利用有限元方法对W粉试样在烧结中的电热效应进行了数值模拟,得到烧结过程中电流密度、能量密度以及温度场分布。结果表明:放电等离子体烧结升温速率快,半径大小影响模具轴向温度梯度,试样径向有较高的温度梯度,影响烧结后试样的均匀性。     

尖板间隙直流放电的极性效应

为了分析气体放电特性，通过气体间隙放电实验，在常温常压下，研究气体的非自持放电和自持放电过程和放电的相关特性。实验结果表明：在直流高压作用下，无论尖极性正负，都随着间隙长度的增加，击穿电压也相应升高，同时也表现出极性效应，在相同的间隙距离下，尖为正极性时电晕起始电压比负极性时的起始电晕电压高，尖为正极性时击穿电压比负极性时的击穿电压低。     

氖氩混合气体辉光放电发射光谱法测定钢样中铝的分析特性(英文)

研究了在Ne-Ar混合气体辉光等离子体中铝的原子及离子发射光谱线,并与纯Ar和纯Ne辉光等离子体进行了比较。在不同的放电气体环境下,Al发射线的相对强度不同。在Ne为放电气体时,可以观察到由4f→3d跃迁而产生的AlⅡ358.71 nm和AlⅡ358.66 nm两条发射线,而这两条线在以Ar为放电气体时不会产生。这种现象的原因是由于4f激发态是由Al原子和Ne离子的共振电荷转移碰撞而选择性高几率的产生的。由于亚稳态的Ne与Ar原子的彭宁碰撞会产生大量的Ar离子,因此在Ne等离子体中加入少量的Ar气时,会增     

在冶金熔体中产生直流辉光等离子体的控制电路

论述了等离子体的特性以及在冶金熔体中应用直流辉光等离子体的意义，阐述了如何根据直流辉光等离子体的电路特性熔体的的特殊条件设计产生直流辉光等离子体的控制电路，并用低熔点的熔融金属铅和钢液作为阴极对该电路进行了测试。     

常压介质阻挡放电非平衡等离子体渗氮研究

利用介质阻挡放电，在自行研制的设备上进行常压非平衡等离子体渗氮的研究。研究表明，该新工艺不仅在很短时间内在试样表面得到很深的渗层和白亮层，而且省去了真空放电下必须的真空设备，整个工艺过程操作简便，是一种很有发展前景的新工艺。     

碎矿工艺的新研究

当前苏联研究并且圓滿地实驗了新的碎矿工艺—高压放电液压碎矿法。当在工业中还是处于工业性試驗的时候,苏联学者尤特金就早已指出了高压放电液压效应用于碎矿的嶄新前途。图1是尤特金所研究制定出來的高压放电液压的电路簡图。它的工作原则是:电压高达30～100仟伏在液体里产生火花放电;伴随高压放电液压效应,而发揮它巨大的冲量,使矿石破碎。电压、电容和火花放电間隙,对于碎矿的效率有决定性的意义。图2是高压放电液压磨的示意图。矿石从矿仓进入到磨体里。这个磨体壁的上部接有水管,它能够适量地供給生产用     

正交磁场对电火花单脉冲放电中电蚀凹坑的影响规律

电火花放电通道在正交磁场的作用下向洛伦兹力方向偏转、延伸,进而导致电蚀凹坑形貌发生变化,研究磁场辅助电火花加工(MF-EDM)过程中电蚀凹坑的形貌变化规律及特点,对进一步明晰电火花加工机理具有重要意义. 基于MF-EDM气中单脉冲放电试验,使用表面轮廓仪观测电蚀凹坑延伸长度、深度、宽度及放电起始点偏移量,并得出磁场及放电参数对电蚀凹坑的影响规律. 结果表明:电蚀凹坑长度随着磁感应强度、开路电压的增大而增大;电极外伸长度的影响结果相反;电蚀凹坑深度随着磁感应强度、开路电压、电极外伸长度的增加没有明显的变化规律;电容与磁感应强度存在最优参数组合以使凹坑长度最大;随着磁感应强度及放电能量的增加放电起始点的偏移量增加.      

On the effects of circuit parameters on electrical behaviour of metallic powders subjected to high rate discharge compaction process

ABSTRACT

In this paper, an attempt is made to investigate the effects of the resistance, voltage, capacitance and input energy during the high rate discharge compaction process. The governing differential equation is complicated to solve due to the resistance change during the discharge. An alternative method is presented to solve the equation numerically by substitution of experimentally obtained resistance curves under different circuit conditions. The experimental results reveal that an increase in voltage beyond the breakdown voltage causes a significant increase in current peak as well as number of conducting fibres. Increasing capacitance at constant voltage leads to reduction of instantaneous values of resistance and alteration in cyclic variation of current trace. A high discharge voltage and a minimum level of capacitance are required to obtain full number of longitudinal fibres and avoid molten channel formation, respectively.     

宝钢电厂采用电子束法SO2减排技术的探讨

宝钢的环境方针、目前的环境状况及可持续性发展都要求宝钢电厂尽快上脱硫装置,以削减SO2的排放.在几种成熟的脱硫工艺中,电子束法烟气净化工艺在宝钢电厂有一定优势,荐为首选.     

High-efficiency shock-wave generator for extracorporeal lithotripsy

In extracorporeal lithotripsy, the electro-acoustic efficiency of electrohydraulic generators is limited by the inductance of the electrical discharge circuit. A new shock-wave generator is described that uses a coaxial discharge line enabling electro-acoustic efficiency to be greatly increased. The line is built using a para-electric ceramic with a relative dielectric constant of 1700, manufactured for use in high-voltage impulse mode. A coaxial spark gap, with minimal inductance, has been developed to obtain the triggered breakdown of the discharge line. Shock waves are created with a coaxial electrode plugged directly into the spark gap and immersed in an electrolyte of degassed saline. Electrode gap and electrolyte resistivity are adjusted to match the resistivity of the electrolyte volume between the underwater electrodes to the characteristic impedance of the line. The discharge line generates in the medium a rectangular current pulse with an amplitude of about 6000 A and a rise time of 50 ns. Compared with conventional generators, measurements of the expansive peak pressure pulse show an increase of 105% at 10 kV, 86.5% at 12 kV and 34.5% at 14 kV charging voltage. Electro-acoustic efficiency is found to be 11% instead of 5.5% for a conventional discharge circuit.     

Research on Eliminate Micro-Shorted MH/Ni Batteries

There are two methods for selecting micro-shorted MH/Ni batteries out from all formationed.cells.One is to judge by the decrease of open circuit voltage which takes longer standing time to eliminate efficiently and does not work very well when the coverage of open circuit voltage is big.Another is to judge by discharge capacity of charged cells, this can not only meet the requirement of MH/Ni battery stored in charged state, but also has the advantages of being easier to read out, good accuracy and taking shorting standing time etc, is a proper way to be used on the production line.     

玻尔兹曼分布研究辉光放电等离子体中铁原子谱线的激发机制

采用玻尔兹曼分布法,通过不同的放电参数,例如外加电压、电流和气压等,研究了辉光放电等离子体中激发能量为4.1～7.0 eV的铁原子谱线激发机制。低激发能量曲线很好地拟合了正玻尔兹曼分布,然而较高激发能量的原子谱线与线性玻尔兹曼曲线有很大偏差。其结果可能是由于较低等级激发由热碰撞引起,而另一方面,铁原子高位等级的激发则是铁原子和氩或氖亚稳原子间的碰撞引起的。     

ARL4460火花放电原子发射光谱仪电路板故障分析与维修

Thermo fisher公司的ARL4460火花放电原子发射光谱仪(以下简称光谱仪)在国内各大钢厂的实验室有着广泛应用,其具有一次分析元素多、范围广、速度快,操作方便且检出限低、精确度高等优点。介绍了光谱仪设备控制系统电路板(以下简称ICS)上芯片损坏后的故障现象、检查和处理方法;低压电源电路板上5 V供电点乱元件损坏的故障现象、检查和处理方法。为实验室维护人员提供一种该仪器电路板故障的修复思路,帮助维护人员快速恢复电路板故障,节约备件成本。     

Effect of electrolyte concentration on low-temperature electrochemical properties of LaNi5 alloy electrodes at 233 K

The effect of KOH electrolyte concentration on low-temperature electrochemical properties of LaNi5 alloy electrodes at 233 K was studied. The results indicated that the electrolyte concentration had great influence on discharge capacity and discharge voltage plateau of LaNi5 alloy electrode at 233 K, and the highest discharge capacity and discharge voltage plateau were both obtained at 6 mol/L KOH. When the KOH electrolyte concentration changed from 5 to 9 mol/L at 233 K, the high rate discharge ability (HRD) had the same change tendency as the diffusion coefficient, but the exchange current density did not change significantly, which implied that hydrogen diffusion was the control step at low temperature 233 K for discharge process of LaNi5 alloy electrode.     

Functional morphology of the spinal canal after endplate, wedge, and burst fractures

The plasma-ion shower method is an effective technique for the SEM examination of un-coated electrically non-conductive specimens. However, milling damage to specimens cannot be prevented by the irradiation method using accelerated Ar ion beam. We, therefore, applied positive ions obtained by plasma discharge to the specimen like a shower by reflecting from the target electrode surface. He, N2 or Ar was used as the environmental gas, and the discharge voltage was varied from 200 V to 1000 V. At 5 kV to 25 kV of SEM accelerating voltage, it was possible to visualize un-coated hard and soft biological and inorganic specimens under 5 mA or 10 mA of discharge current and 5 min or 10 min of processing time.