微负压炭化灰化一体机的研制

基于干法灰化法,提出了一种微负压油样及有机物的炭化灰化一体化密闭预处理方法,研制了相应设备,实现了微负压密闭条件下油品无氧蒸发,氮氛热解、无焰炭化、有氧灰化等步骤的自动化与绿色化;消除了干法炭化灰化法带来的环境污染和安全隐患,批量化炭化灰化油样,降低劳动强度,提高油品金属离子测试结果精准度,用于实际油品的灰分测定及其金属离子含量测定中的样品预处理,结果满意。     

自主创新微波快速灰化马弗炉

介绍了自主创新研制成功的WM-2型微波快速灰化马弗炉的结构和技术性能特点及其样品灰化分析方面的应用。     

基于干灰化法和比色法的空心胶囊中铬含量快速测定方法研究

本文研究了一种基于干灰化法和比色法的空心胶囊中铬含量快速测定方法及相应的便携式比色分析仪.实验中考察了显色体系内各试剂浓度、显色时间和显色温度等条件,结果表明溶液中铬浓度在0.01 ～ 1.5 mg/L范围内时体系线性关系良好,相关系数r=0.99945;采用标准加入法对样品灰化时间进行了优化,结果表明灰化时间为3 h时,回收率可达到最佳水平97.15％.为保证仪器的便携性,在设计中采用峰值波长为520 nm的超高亮发光二极管(LED)作为光源,采用锂电池作为电源,采用非色散方案简化光路.与国家标准方法(微波消解—石墨炉原子吸收法)的实际样品比对结果表明,本文方法测定结果的相对误差小于5％,适于对空心胶囊中铬含量的快速测定.     

基于微波的粮食水分智能化测试仪

为了测定粮食中的水分,系统以STC89C58为控制核心,通过重量采集装置BS-124S采集样品的重量数据,单片机可以控制微波装置以不同的强度对样品进行快速干燥,通过步进电机控制样品托盘,对四组样品进行依次称量,实现了对多个样品水分的准确快速的检测.系统具有良好的人机交互功能,通过LCD显示模块可以对所有的设置和测量参数进行实时显示,通过键盘输入模块可实现微波加热时间、微波加热强度等功能的设置.     

FAAS法对制备样品方法的研究

在ＦＡＡＳ法分析中，样品预处理始终占有极为重要的位置。本文比较了三种样品消化方式，即传统酸消化法、灰化法及微波消化法。传统的消化方式因其过程长、速度慢、效率低，而且被测元素易受到损失及易污染等不足。而微波是一种非常快捷、省时、省试剂和无污染的消化方式。通过对标准物质贻贝中的铜、锌、铁的测定结果证明微波消化方式比传统的消化方式优点多。     

微波消解—ICP-AES法测定镁质耐火材料中次量元素

采用微波消解技术进行样品前处理,建立了电感耦合等离子体原子发射光谱法同时测定镁质耐火材料中次量元素的分析方法。通过大量条件试验,确定了测定的最佳条件。对标样和样品进行测定,结果表明,该方法简便、快速,数据准确、可靠。     

附生苔藓对大气中重金属元素的生物富集中子活化方法研究

苔藓生物监测器对重金属的特征富集能够反映出大气沉降中的重金属污染程度 ,利用中子活化法的多元素同时分析技术测定苔藓植物体内的元素含量时 ,样品的均一性十分关键。利用新型陶瓷纤维马弗炉的快速灰化方法 ,可以高效地解决这一问题。同时 ,灰化样品大大减少了样品的体积 ,节省了照射孔道空间 ,避免了其它元素的污染。通过协作实验室的方法对比 ,同种苔藓的两组测定结果表明灰化样品没有造成元素的损失。     

微波消解原子吸收法测定米粉中铁含量

采用湿法消解技术溶样,用原子吸收（AAS）法测定米粉中铁的含量。通过对微波程序的研究,建立米粉、奶粉等的微波消解方法。该方法与传统马弗炉高温灰化消解方法及湿法消化比较,具有准确、简便、安全、省试剂、污染少、消解完全等优点。方法回收率为96%～106%。RSD（n=7）均小于2%。实际样品对比分析结果表明,方法具有良好的准确度,适于奶粉、米粉、豆粉等食品的快速分析。     

微波消解原子吸收法测定米粉中铁含量

采用湿法消解技术溶样,用原子吸收(AAS)法测定米粉中铁的含量。通过对微波程序的研究,建立米粉、奶粉等的微波消解方法。该方法与传统马弗炉高温灰化消解方法及湿法消化比较,具有准确、简便、安全、省试剂、污染少、消解完全等优点。方法回收率为96%~106%。RSD(n=7)均小于2%。实际样品对比分析结果表明,方法具有良好的准确度,适于奶粉、米粉、豆粉等食品的快速分析。     

微波消解原子吸收法测定米粉中铁含量

采用湿法消解技术溶样,用原子吸收（AAS）法测定米粉中铁的含量。通过对微波程序的研究,建立米粉、奶粉等的微波消解方法。该方法与传统马弗炉高温灰化消解方法及湿法消化比较,具有准确、简便、安全、省试剂、污染少、消解完全等优点。方法回收率为96%～106%。RSD（n=7）均小于2%。实际样品对比分析结果表明,方法具有良好的准确度,适于奶粉、米粉、豆粉等食品的快速分析。     

A Laser-Based Apparatus for Estimating the Hydrogen Diffusion Constant in Gas Mixtures

A laser-based apparatus for determining the hydrogen diffusion constant in gas mixtures is described. The main units of the apparatus are a diffusion chamber and a computer-based laser system for the selective diagnostics of hydrogen in gas mixtures by coherent anti-Stokes Raman scattering (CARS) in combination with biharmonic pumping based on stimulated Raman scattering. The diffusion constant is estimated by approximating the experimental data that describe changes in the hydrogen concentration with time at a fixed point in the diffusion chamber and comparing them to the exact solution to the diffusion equation for the chosen one-dimensional experimental geometry.     

某微波器件精密制造技术研究

雷达产品所用微波器件具有结构复杂,精度要求高,成本高,多采用加工易变形的有色金属材料等特点,为了保证质量,在提高其设计的工艺性的同时,需要对其进行仔细的工艺设计和严格的制造过程控制.文中介绍了一种较复杂微波器件的精密制造技术,提出并讨论了其制造过程要点,重点分析了造成其加工变形的主要因素以及在变形控制方面采取的具体措施.实践证明所采用的制造技术是成功的,为类似问题的解决提供了有益的参考.     

Environmental chamber for in situ dynamic control of temperature and relative humidity during x-ray scattering

We have designed, constructed, and evaluated an environmental chamber that has in situ dynamic control of temperature (25 to 90?°C) and relative humidity (0% to 95%). The compact specimen chamber is designed for x-ray scattering in transmission with an escape angle of 2θ = ±30°. The specimen chamber is compatible with a completely evacuated system such as the Rigaku PSAXS system, in which the specimen chamber is placed inside a larger evacuated chamber (flight path). It is also compatible with x-ray systems consisting of evacuated flight tubes separated by small air gaps for sample placement. When attached to a linear motor (vertical displacement), the environmental chamber can access multiple sample positions. The temperature and relative humidity inside the specimen chamber are controlled by passing a mixture of dry and saturated gas through the chamber and by heating the chamber walls. Alternatively, the chamber can be used to control the gaseous environment without humidity. To illustrate the value of this apparatus, we have probed morphology transformations in Nafion(?) membranes and a polymerized ionic liquid as a function of relative humidity in nitrogen.     

Meetings & Symposia

A multifunctional sampling chamber was developed for laser-induced breakdown spectroscopy (LIBS) for field elemental analysis. The apparatus consisted of a chamber, an optical module, and a spectrometer controlled by lab-constructed software to achieve full automation. A number of samples may be simultaneously and automatically measured since a servomotor rotated eight sample compartments in the chamber that may filled with inert gas to enhance the intensity of the signal. A heater in the sample compartments allowed variation of the temperature. The system was used for the rapid and direct measurement of solid, liquid, and powders after simple preprocessing. The apparatus was evaluated for the qualitative analysis of drilling fluid. Eleven elements, Zn, Ni, Fe, Mn, Si, Al, Cr, Ca, Mg, K, and Na, were detected. The results demonstrate successful application for the analysis of multiple elements by LIBS.     

Development of compact linear accelerator in KBSI

The compact linear accelerator using a 28 GHz ECRIS is under construction in KBSI, South Korea. The main capability of this facility is the production of fast neurons for the neutron radiography. The designing of a superconducting magnet, microwave transmission system, beam extraction, and plasma chamber of ECRIS were finished. The nominal axial design fields of the magnets are 3.6 T at injection and 2.2 T at extraction; the nominal radial design field strength at the plasma chamber wall is 2.1 T. We already installed 10 kW, 28 GHz gyrotron, and tested a microwave power from gyrotron using a dummy load. The current status will be discussed in this paper.     

高透光率金属网栅微波/红外二色波组合器

为了实现微波/红外半实物仿真技术中的信号耦合,提出了一种基于高透光率金属网栅的宽频段二色波组合器结构,并建立了金属网栅二色波组合器的微波反射特性和红外透射特性分析模型。为了验证基于高透光率金属网栅的二色波组合器的可行性和分析模型的有效性,利用激光直写工艺在锗基底上制作了金属网栅二色波组合器样片;为了减小倾斜入射时不同极化情况下微波反射率的差异,金属网栅垂直极化和平行极化方向的周期分别设为500μm和400μm。在微波暗室中测量了金属网栅二色波组合器样片在12～18GHz频段的微波反射率,并利用傅里叶红外光谱仪测量了样片在10～12μm波段的红外透射率。计算和测量结果显示,高透光率金属网栅二色波组合器的微波反射率优于-1.5dB,红外透射率约为83%,表明高透光率金属网栅可用作一种新型的宽频段微波/红外二色波组合器。     

An apparatus for immersing trapped ions into an ultracold gas of neutral atoms

We describe a hybrid vacuum system in which a single ion or a well-defined small number of trapped ions (in our case Ba(+) or Rb(+)) can be immersed into a cloud of ultracold neutral atoms (in our case Rb). This apparatus allows for the study of collisions and interactions between atoms and ions in the ultracold regime. Our setup is a combination of a Bose-Einstein condensation apparatus and a linear Paul trap. The main design feature of the apparatus is to first separate the production locations for the ion and the ultracold atoms and then to bring the two species together. This scheme has advantages in terms of stability and available access to the region where the atom-ion collision experiments are carried out. The ion and the atoms are brought together using a moving one-dimensional optical lattice transport which vertically lifts the atomic sample over a distance of 30 cm from its production chamber into the center of the Paul trap in another chamber. We present techniques to detect and control the relative position between the ion and the atom cloud.     

Improved apparatus for trapped radical and other studies down to 1.5 K

This note describes a Dewar system and associated apparatus for trapped free radical and other studies at temperatures down to 1.5 K. Cylindrical and rectangular microwave cavities can be used.     

An accelerated simulation test apparatus for evaluating elevated temperature erosion-corrosion behaviour of iron and steel in gas-solid flows

This paper introduces an accelerated simulating test apparatus for evaluating high temperature erosion-corrosion behaviour of iron and steel in gas-solid flows. This device is designed to investigate the high-temperature erosion-corrosion properties of materials and to optimise anti-erosion-corrosion measures for iron and steel parts. It simulates the working conditions of the pipes in an economiser. We have shortened the test duration by increasing the density of abrasive particles in the fluids. The test set up is composed of six main parts, including the blowing system, heating system, feeder/mixer, erosion-corrosion chamber, and loading system, the cooling system, and the control system. Four years' operation has shown that the repeatability for the experimental results is good. The SEMs of the worn surfaces of both specimens and actual pipes in the economiser show that they are consistent with each other. Four years' operation has shown that the test apparatus is characterised by reliability and good simulation ability. Both practical and theoretical research work can be done with this device.     

Development of variable temperature instrument for sensor calibration

An experiment to calibrate temperature sensors at cryogenic temperature has been performed. The main objective of this study was to develop a precise instrument for calibrating the temperature sensors over a temperature range of 4 K to approximately room temperature without liquid helium. The instrument consists of radiation shields, a sensor block, an electric heater, a cryocooler and a vacuum chamber. In a vacuum chamber, the cold head of the cryocooler is thermally anchored to the sensor block to bring the apparatus to a desired temperature. An electric heater is placed at the second stage of the cryocooler to control the temperature of the sensor block. The entire apparatus is covered by radiation shields and wrapped in multi-layer insulation to minimize thermal radiation in a vacuum chamber. The dimensions of components including instrumental wires are optimized to reduce total heat invasion from room temperature into cryogenic temperature. The vacuum chamber is pumped down and cooled to cryogenic temperature by a cryocooler. The resistance of each temperature sensor is measured at steady state as well as cooling down and warming up cycles, and the performance of calibration is discussed with respect to the sensitivity and resolution.