非接触式酸、碱浓度计的设计与实现

针对目前国内接触式在线酸、碱浓度计寿命低、误差大及电极易污染的缺点,提出一种非接触式在线酸、碱浓度计的测量原理及实验电路,并给出了电路主要参数及实验数据。     

在线钠离子分析仪表在生产中的应用分析

钠表,既钠离子计,用来测定钠离子浓度的仪器,广泛应用于热电厂及其他工业锅炉水、蒸汽冷凝水等的检测分析。采用离子选择电极,从电极电位的变化来检测溶液中被测离子浓度的变化。本文针对HACH公司的9245钠分析仪、ABB的8037型钠分析仪及核工业北京化工冶金研究院的HGY2068钠分析仪3个厂家的钠分析仪的在线运行中的测量原理、技术指标、操作校准、维护和故障处理等方面对比优劣,提出维护建议。     

聚醚三酰胺钠离子电极的制备和应用

用五种合成的开链聚醚三酰胺制成了PVc膜钠离子电极,并与类似结构的ETH227电极作了比较.研究了载体结构与电极性能的关系,含有适当长度碳链的几种酰胺适于作钠电极的载体.PVC涂层玻璃膜钠电极性能良好,可用于恢复已失效的某些玻璃膜钠电极的功能.     

国产数字航摄仪成功用于测绘生产

运用国产SWDC-2型数字航空摄影仪获取的四川宜宾摄区航摄成果，不久前通过验收。这标志着国产数字航空摄影仪成功用于测绘生产。验收专家认为，此举填补了国内空白，为国产化数字航空摄影与航空摄影测量为一体的整体解决方案奠定了基础。     

催化进口气压机浮环密封国产化实践

介绍了催化裂化装置中2MCL527型气压机浮环密封国产化实践。经认真测绘和核算，采用国产材料替代后，该密封机械性能基本达到进口原件的指标。     

谈对点焊机冷却水的要求

我厂使用的3台DN-25型点焊机,由于是采用地下水对电极头进行冷却,所以,使用一年后就出现了上下电极头每点焊1～2天就需要修复一次,数天后就需要更换电极头的现象。既影响生产又浪费材料。分析其原因,我们认为:我们使用的冷却水是未经过软化处理的硬水,在地下水中含有较多的矿物质。在点焊机工作时,冷却泵抽出的冷却水通过点焊机上下电极座水道孔,送到电极头,然后返回到冷却水箱进行循环冷     

国内外动态

慢走丝切割机铜电 极丝的国产化陈翔 近年来,我国进口的及引进国外专用技术(know-how)生产的慢速走丝电火花线切割机需用铜丝作为工具电极(国产高速走丝线切割机采用钼丝)。电极丝属易耗品,每台机床每班消耗约1.5公斤,每公斤进口价需16.6美元。当前全国这类机床拥有约200台,如以每台每年实际工作250个班计,每年需75吨电极丝,耗外汇127.5万美元,数量相当可观。为使电极丝国产化,上海有色金属研究所与苏州电加工机床研究所分别研制成功了铜电极丝。通过鉴定,并投入批量生产。 这种电极丝是以锌黄铜为基础,加上微量铝等添加元素,或经熔炼、锻打…     

HJD-79型恒电流自动滴定仪及水中硼的测定

HJD-79型恒电流自动滴定仪全部采用国产集成电路组装而成,线路结构简单,小型轻便,造价低廉,能自动控制滴定终点并及时报警。它主要包括恒电流源电路、补偿式测量电极电位装置、比较控制电路和自动报警线路及双组稳压电源等。本仪器的恒电流源分为10档——50、100、200、500uA和1、2、5、10、20、50mA可供选择,精度优于±0.1％。电极电位控制范围     

超高面载量钠离子电池电极研制成功

正钠离子电池具有原材料丰富、易得,成本低,安全性高等优点,在中低速电动汽车、电动自行车、储能等领域具有广阔的应用前景。但由于钠离子具有较大的相对原子质量及粒子半径,钠离子电池较锂离子电池比能量和比功率偏低。开发高面容量电极是提高电池比能量的有效方法之一。中科院大连化学物理研究所研究员李先锋、副研究员郑琼带领的研究团队,在钠离子电池超高面载量电极研究方面取得新进展。据介绍,电极组分的随意堆叠将在电极上形成高弯曲度的多孔结构。     

CF7454转阀式动力转向器力特性曲线的优化设计

CF7454转阀式动力转向器是广汽长丰汽车(惠州)有限公司,根据日本KOYO公司转向器样机自主开发设计并制造的循环球转阀式动力转向器,力特性满足样机标准。根据猎豹汽车新车型开发配套及国产化要求,将CF7454转向器的力特性曲线向豫北ZDZ7型转向器的力特性改进,以满足国产越野车手力特性的特殊要求。详细说明了该力特性曲线优化设计过程。     

Large area mass analyzer instrument for the chemical analysis of interstellar dust particles

A new instrument to analyze the chemical composition of dust particles in situ in space has been developed. The large target area ( approximately 0.2 m(2)) makes this instrument well suited for detecting a statistically significant number of interstellar dust grains or other dust particles with a low flux. The device is a reflectron-type time-of-flight mass spectrometer that uses only flat electrodes for the generation of the parabolic potential. The instrument analyzes the ions from the impact generated plasma due to hypervelocity dust impacts onto a solid target surface. The SIMION ion optics software package is used to investigate different potential field configurations and optimize the mass resolution and focusing of the ions. The cylindrically symmetric instrument operates with six ring electrodes and six annular electrodes biased to different potentials to create the potential distribution of the reflectron. The laboratory model of the instrument has been fabricated and tested. Hypervelocity dust impacts are simulated by laser ablation using a frequency doubled Nd:YAG laser with approximately 8 ns pulse length. The experimental data show typical mass resolution m/Deltam approximately 200.     

A Converging Wall-Jet Instrument for Ion Selective Electrode Dynamic Response Studies

Abstract

Ion selective electrodes are used to conduct real-time measurements of gaseous thermal degradation products from halon replacement experiments. Response characteristics of these ion selective electrodes are needed to address potential interferences and surface poisoning experienced under field conditions. The design and the fabrication of an in situ, converging wall-jet instrument for the measurement of the dynamic responses of ion selective electrodes are described. Various time delays associated with the generation and detection of ion activity steps have been quantitatively determined.

Dynamic response measurements for iodide steps on a Corning iodide/cyanide ion selective electrode are comparable to those obtained on the best of the earlier instrument designs, the in situ, switched wall-jet instrument. The advantages of the converging wall-jet instrument over the switched wall-jet instrument are identified.     

小型飞行时间质谱装置的构建

飞行时间质谱仪（TOF MS）在准确度、分辨率、灵敏度、质量上限、分析速度等方面具有优势，在生命科学等领域发挥着重要作用。目前商用飞行时间质谱仪已经比较成熟，但仪器尺寸普遍较大，且价格昂贵，维护困难；而小型仪器则面临分辨率较低等问题。提高小型飞行时间质谱仪的分辨率，降低购置成本和维护成本，对于飞行时间质谱仪的大范围推广有着重要意义。本工作构建了一套分辨率较高的小型飞行时间质谱装置，包括真空系统、离子源、锥孔、引出加速及偏转模块、离子反射镜模块、探测器模块、电路系统等。该仪器主体尺寸较小（0.5 m×0.5 m×0.7 m），飞行管长度仅0.25 m。由于采用了模块化设计思路，各个模块之间独立封装，仪器的维护、升级工作简单易行。该仪器的关键模块采用创新设计，使得在m/z 2 000处分辨率可达4 200。     

离子色谱法测定降水中钾、钠、铵

本文讨论了用离子色谱法测定降水中的钾、钠、铵。实验表明,对降水中钾、钠、铵的测定,用离子色谱法更方便、快速,具有较高的准确度和较好的精密度,通过和光度法进行比较,我们认为当测定降水中的钾、钠、铵时,离子色谱法可代替光度法。     

PCB离子阱质量分析器

目提出了一种利用普通印刷线路板（Printed Circuit Boards,PCB）加工构造离子阱质量分析器的新方法。用该方法制造的PCB离子阱仅由四块PCB平板电极和两块不锈钢薄片电极构成,具有结构简单、加工容易和价格低廉等优点,非常适合制造成低成本的便携式质谱仪。初步实验结果表明,应用这种方法所建造的PCB离子阱质谱仪系统,可以获得优于400的质量分辨率和300Thomson以上的质量扫描范围。     

Scanning multiple collector electrostatic analyzer with application to plasma potential measurement

Three collector electrodes have been located accurately on the focal plane of a parallel-plate electrostatic energy analyzer to form an exit slit matched to a large inlet slit by the design magnification ratio. In bench tests with a nearly uniform, monoenergetic K+ beam at 5 kV these collectors have been found to provide a scanning capability for measurement of the energy of such a large beam with sufficient precision, DeltaV/V approximately +/-10(-3), to resolve plasma potential in heavy ion probe diagnostic studies of magnetically confined plasmas. In such studies a wide entrance slit is needed because of low signal levels. The method provides enhanced resolution with greater facility than obtainable with a feedback approach used in prior investigations. A nearly triangular sharply peaked profile was observed on the center collector providing the desired resolution. Scans at various entrance angle settings have been made and beam size and peak location results compared with predictions based on the existing model for an ideal instrument.     

总辐射表性能评价

根据WMO和ISO关于对总辐射表的性能指标的要求,对我国气象观测台站使用的总辐射表(型号为DFY4和TBQ-2)进行了全面的性能测试。主要考核了灵敏度和长期稳定性,以及非线性、温度特性、余弦响应、方位响应、倾斜响应、时间响应、零位漂移等对灵敏度的影响。通过大量的实验数据和分析研究,得出了总辐射表测量误差的主要来源。这对于控制仪器质量,提高太阳总辐射测量的准确度以及对太阳辐射的研究是非常有益的。     

Numerical estimation of ion transport and electroosmotic flow around a pair of cylindrical electrodes in a microchannel using immersed boundary method

This paper investigates the ion transport and electroosmotically induced flow around the cylindrical electrodes under both direct current (DC) and alternating current (AC) fields. The Poisson-Nernst-Plank (PNP) equations governing the ion transport around the ideally polarizable electrodes are solved numerically by neglecting the Stern layer effect. The fractional-step (FS) based decoupled solver is used in time integration of the ion-transport equations. A new immersed boundary (IB) methodology is described for imposing no-flux boundary conditions of ion concentration on the electrodes. A fully implicit coupled solver is also developed for calculating the ion transport around a pair of rectangular electrodes. The validity of the decoupled solver is verified by comparing its results with those obtained from the coupled solver. For further confirmation of the validity, the results are also compared with those obtained from the Poisson-Boltzmann model and both results are found to be in excellent agreement. The electroosmotically induced flow field is studied by numerically solving the Stokes equations. The system attains a steady state under DC, where the conduction term of ion transport is balanced by the diffusion term. Until the system attains a steady state for a few ms for the case of DC, fluid flow is induced. The electroosmotic flow under AC is more interesting, in that instantaneous flow oscillates with the frequency double of the applied field and a nonzero steady velocity field persists.     

Cooling of extraction electrode of an ion source in long-pulse operation

Experimental studies were made on the cooling of extraction electrodes of an ion source in the case of long-pulse operation. Copper electrodes with forced water cooling pipes were tested under the condition that an ion beam of 1 to 5 A at 30 keV was extracted for up to 10 s. The average heat loading to the grid are of the electrode was as high as 130 W/cm2. This high heat flux was obtained by a set of electrodes artificially arranged to produce poor beam optics, and hence the high heat loading. Temperature of the ground electrode was measured at two points by thermocouples buried and silver brazed in it, and was kept below 230 degrees C due to a large boiling heat transfer coefficient of the cooling water. No evidences of deformation or deterioration of the electrodes was observed after repetitious beam extraction. This heat loading was still a half of that on the grid of the ion source for the JT-60 NBI.     

基于电喷雾电离源质谱仪系统的八电极线性离子阱性能研究

八电极线性离子阱在前期的理论模拟研究中取得了较好的质量分析性能,为验证理论模拟结果,选择其中最优的结构参数,设计、加工并组装了八电极线性离子阱实物,以此为基础搭建电喷雾电离源质谱测试系统。在传统射频电压施加模式下,测试八电极线性离子阱的分析性能。当扫描速度为765 u/s时,八电极线性离子阱获得离子峰的半峰宽可达0.3 u,对应利血平（m/z 609）的质量分辨率为2 030。当分析浓度为10 mg/m3的利血平样品时,对应的质谱峰信噪比可达45.8。本文进一步研究了扫描速度对质量分辨率和灵敏度的影响,实现了离子碰撞诱导解离,分析了不同浓度的25羟基维生素D2标准样品,线性动态范围可达4个数量级。结果表明,八电极线性离子阱具有良好的分析性能,可为结构简化线性离子阱的研究提供全新思路,推动小型化离子阱质谱仪的研究进展。