A 1-MJ capacitive energy storage

A capacitive energy storage is intended for generating high-power current pulses. The setup consists of two capacitive energy storage modules, a control console, and a cable collector for connecting a load to the setup. Each module is a capacitive energy storage with a 0.5-MJ stored energy and 18-kV voltage, which is based on eight capacitor cells with reverse switch-on dynistors as switches. The module volume is 1.3 m³. The semiconductor switches in the capacitor cells are activated by light pulses, which are transmitted from the control console through fiber-optic cables. The unit is designed for operating in the programmable discharge mode, at which the semiconductor switches in the capacitor cells are switched on nonsimultaneously but in accordance with a specified program. When the discharge of all the cells is switched on simultaneously and the load is short-circuited, the maximal amplitude of the output current pulse is 800 kA. The rise time of the discharge current pulse of the cell is 150 μs.     

A low-temperature quartz microbalance

The design of a low-temperature quartz microbalance based on standard radio engineering quartz resonators is described. The sensitivity of the balance on PK88CP, PK104-5M, and PΓ-07 resonators at a 5-K temperature is determined. Special features of the practical use of the microbalance in the FTIR matrix insulation spectroscopy are considered. It is shown that, for films of solidified inert gases, one may ignore the dependence of the sensitivity on the frequency shift below 0.5–1.0% of the initial frequency of the resonator. Original Russian Text ? A.Yu. Ivanov, A.M. Plokhotnichenko, 2009, published in Pribory i Tekhnika Eksperimenta, 2009, No. 2, pp. 166–169.     

A micro-magnetic bearing using capacitive axial displacement sensing

This paper describes a one-axis-controlled micro-magnetic bearing (MMB) system that utilizes capacitive axial displacement sensing (CADS). The axial rotor displacement is measured using the variation in capacitance between the rotor and the electromagnet cores, which take the form of a flange. An MMB structure is proposed and designed to realize the CADS and achieve high magnetic stiffness for supporting the rotor. Experimental results for an MMB with 6-mm-diameter rotor show that the CADS was able to measure the axial rotor displacement with a resolution of about 1 μm in 10 kHz bandwidth and ±20 μm range. By using the CADS output as a feedback signal, the rotor could be levitated stably and rotated at about 10,000 rpm without external displacement sensors.     

A polyalphaolefin with exceptional low-temperature properties

A new process has been discovered for the production of low-viscosity PAO fluids in high yield. In particular, the new process can be used to produce a mixture of decene dimers that has low-temperature properties which are superior to the properties of decene dimers produced by the conventional PAO process.     

纳米级电容测微系统的研究

本文首先介绍非接触式高精度电容测微仪的基本工作原理,进而详细论述纳米级电容测微技术中所涉及到的非线性误差、环境噪声等的关键技术问题,对典型驱动电缆方案作比较。根据原理模型,给出仪器的主要结构。对仪器自身产生的各种误差进行详细的分析,并提出相应的消除或修正方法。换用不同有效直径的传感器可以使仪器分辨率最小达到0 1nm ,测量范围±2～±5 0 μm ,满量程非线性度优于0 5 %。该仪器可广泛应用于通过串口、USB口通信的高精度的动、静态微位移测量及纳米定位     

A low-power current regulator for low-temperature thermometers

A battery-supplied current regulator for low-temperature thermometers is described. The regulator operates in the range 1–10 µA and consumes a current of 0.12 mA.__________Translated from Pribory i Tekhnika Eksperimenta, No. 2, 2005, p. 146.Original Russian Text Copyright © 2005 by Tsymbalenko.     

MEMS电容应变传感器

本文详细介绍了一种用硅玻璃键合工艺制作的微型梁式电容应变传感器,通过ANSYS软件并结合MEMS器件的特点进行优化,设计并制作了由MEMS工艺实现的微型梁式电容应变传感器.为保证应变器件稳定工作,在测量电路中加一直流静电驱动电压在电容器的极板之间,以保证建立的电场在两极之间产生一个静电力,引起膜片发生向下形变的弯曲,从而保证作用在轴向的应力不会使应变梁产生失稳.文中详细给出了工艺流程和测试结果,通过实验测试证明,用这种方法制作的电容应变器件具有良好的线性、较小的滞后和稳定的工作特性,其中应变灵敏度达10 fF/MPa,测量误差小于1%FS.     

A low cost capacitive bridge based on voltage drop balance

The proposed bridge has a simple analog design featuring few components and may be implemented inexpensively at any laboratory. Yet, it is characterized by a low input stray capacitance (1 pF in the prototype with margin for improvement) and a very good accuracy, in terms of measurement uncertainty and repeatability: the method of balancing successive readings of the voltage drops across the “capacitor under test” and a reference resistor uses at best the external voltmeter in terms of measurement accuracy and avoid the need for a voltage reference and related stability issues.     

A calorimeter with a capacitive probe for measuring microwave energy

A calorimeter of simple design for measuring the total energy of microwave radiation is described. It operates in the energy range of 0.5 J to 6 kJ; water is used as the absorbing material. A capacitive probe is applied to measure changes in the water volume. The energy absorption factor of electromagnetic radiation in the range of 3–60 GHz is at least 0.9. The calorimeter is insensitive to radiation field nonuniformity over the absorber volume, and its response to microwave radiation is virtually instantaneous. The calorimeter is intended for measuring the radiation energy of beam plasma generators and generators with dielectric structures. Its design makes it possible to simultaneously measure the radiation energy and monitor the beam current.__________Translated from Pribory i Tekhnika Eksperimenta, No. 2, 2005, pp. 103–106.Original Russian Text Copyright © 2005 by Kiselev, Linnik, Onishchenko, Uskov.     

A specimen holder for low-temperature scanning electron microscopy

A miniature vise built into a copper stub is described that holds bulk, pre-frozen, hydrated biological specimens during examination under the electron beam of the scanning electron microscope.     

A high-voltage power supply based on a distributed capacitive energy storage

For the corpuscular plasma heating in the MST plasma device (Madison, United States), an injector of hydrogen atoms with 25-keV energy, equivalent at omic current of >45 A, and 20-ms pulse duration was designed and put into operation at the Budker Institute of Nuclear Physics (Novosibirsk, Russia) in 2009. The pulse repetition rate is 5 min. The output current of the ion source in the atomic injector exceeds 50 A. A high-voltage source with a 1.5-MW power was design ed for the high-voltage powering of the atomic injector. The run duration of the power supply with rated characteristics is >20 ms. The power supply is based on a distributed capacitive energy storage, which allows the power consumption from the industrial network to be reduced down to 10 kW at a pulsed load power of 1.5 MW. The high-voltage power supply smoothly regulates the output voltage from 0 to 30 kV and is capable of being quickly deenergized if high-voltage breakdown of the load takes place. The diagram and structural components of the high-voltage power system of the atomic injector are described, and its test results are given.     

A capacitive storage for a tabletop X-ray laser for dense-plasma diagnostics

The results of investigation of a pulsed capacitive energy storage for a tabletop-type X-ray laser for dense-plasma (up to 3 × 10²² cm^?3) diagnostics are presented. It is assumed that plasma of Ne-like argon is the active medium of the X-ray laser and an electric discharge occurs inside a 150-mm-long ceramic capillary 3–4 mm in diameter. In previous experiments on the SIGNAL accelerator, the main initial conditions for generation of laser X rays were determined and X rays at a wavelength of 46.9 nm were obtained. The pulsed capacitive-energy storage unit is built in the form of a flat capacitor filled with deionized water. It has been revealed that deionized water as the dielectric filling the flat capacitor is not broken down in a 10-mm-wide gap at a pulsed voltage <130 kV and a charging-pulse duration of ～300 ns. In this case, the parameters of the pulsed capacitive-energy storage correspond to those required for generation of laser X rays: a current amplitude in the load of 50 ± 1 kA and a period of the current in the load of 196 ± 2 ns. The small jitter of the duration of the charging pulse (288 ± 6 ns) of the flat capacitor offers a hope for satisfactory synchronization of a laser X-ray pulse with a diagnosed plasma object.     

微机械电容式麦克风的仿真研究

针对麦克风产品开发成本过高问题,对麦克风的制造工艺进行了研究,提出了一种用仿真代替实验的方法,利用Intelli Suite软件中的Blueprint设计麦克风制作过程中所使用的掩膜版图,再利用Intelli Suite软件中Intelli Fab模块对器件进行了微电容式麦克风的工艺流程仿真,仿真出麦克风器件,再利用Intelli Suite软件中的3D BUILDER,TEM两个子模块,仿真得到了微机械电容式麦克风的灵敏度、吸合电压以及固有频率等参数,该仿真过程得到的相关参数能够为微机械电容式麦克风性能的佐证提供参考,并指导学者对微电容式麦克风产品的开发与设计过程。分析结果表明,此过程能够代替实际的开发的制造过程,达到节约产品开发成本的目的。     

A scanner for an ultrahigh-vacuum low-temperature scanning tunneling microscope

A scanner for an ultrahigh-vacuum low-temperature scanning tunneling microscope is described. It has a high resonance frequency (>30 kHz) and a small thermal-drift rate (≤1 nm/°C) at room temperature. The scanner feeds the tip to the sample at a distance of up to 3 mm and positions it in the sample plane on a 4 × 4-mm area. These characteristics of the scanner allow one to study atomic structures at temperature variations from 5 to 300 K with objects under study remaining in view of the microscope. The scanner has a horizontal attachment for a sample with a size of up to 6 × 6 × 3mm and ensures a scanning field of 4.8 × 4.8 × 0.6 μm at 300 K and 0.8 × 0.8 × 0.1 μm at 5 K, as well as the possibility of heating to 150°C and easily replacing the sample and tip with vacuum manipulators.     

Measurement of the thermal coefficient of linear expansion on a speckle-interferometric dilatometer

A design of the speckle-interferometric dilatometer intended for studying thermal expansion of solid bodies at temperatures of 20–100°C is described. The calibration results for the thermal coefficient of linear expansion of copper, Armco iron, and 12Kh18N10T steel samples are given.     

高灵敏度容栅式电子塞规

详细介绍了这种塞规的结构和原理,为在线检测提供了一种新的选择.     

电容传感器线性度标定平台

设计了一种电容位移传感器在线标定平台,用于位移的高精度调节和检测。该平台的运动对称中心轴、测量光路的对称中心轴和传感器的传感轴共轴,故从测量原理上减小了阿贝误差。标定平台具有z/tip/tilt调节功能,保证了传感器的传感面和被测面板的被测面之间的装调对准。介绍了标定平台的组成和标定方法的原理,采用对称平行四边形机构实现了微位移调节,基于柔度矩阵法(CMM)分析了导向机构的输出柔度和行程。试验测得动平台行程为735.162μm,和有限元法(FEM)、CMM计算结果的误差分别为7.410%和4.633%,满足行程误差要求。经过标定补偿后,传感器的线性度由0.014 21%提高至0.006 231%。实验结果显示,该线性度标定方法精度高,标定后的传感器满足位移精密调节机构使用要求。     

高精度容栅式电子卡规

针对容栅式电子卡规分辨率较低、电感式电子卡规功能单一且装配调试难度大的缺点,开发了一种高分辨率容栅式电子卡规。介绍了这种卡规的结构和原理,为在线检测提供了一种新的选择。