A Gravitational Wave Detector Based on a Two-Cavity Laser Measurement System

Results are presented on detecting low-frequency periodic gravitational radiation from binary relativistic astrophysical objects. __________ Translated from Izmeritel'naya Tekhnika, No. 9, pp. 13–18, September, 2005.     

场量测量在变交漏磁检测技术中的应用

介绍了以AD637为基础建立的交变漏磁场测量调理电路,完成了基于A3515霍尔元件的漏磁场场量测量传感器的设计,阐述了交变漏磁场测量的工作原理和测试方法,通过对钢管矩形裂纹的测试结果表明,该设计实现了测试的目的,在对缺陷信号进行分析和处理的基础上,提出了基于"缺陷环"的识别方法.     

Detection of Weak Gravitational Pulses in the Minimum Mode Regime

An amplitude algorithm is considered for detecting weak and rare gravitational pulses in the minimum mode regime on a background of arbitrary additive non-Gaussian noise under conditions of parametric a priori uncertainty.     

磁性液体在均匀磁场中的瞬态双热线导热系数的测试

将封有聚α-烯烃合成油基磁性液体的两玻璃管放置于磁场中,为消除磁场力、重力所引起的磁性液体自然对流的影响,消除端部效应,研制了磁性液体在均匀磁场中瞬态双热线导热系数的实验测量系统,经与蒸馏水、乙醇标准样品的导热系数测量比较,实验装置有较高的测量精度。实验测量了不同方向的均匀磁场对不同体积浓度的磁性液体导热系数的影响。结果显示,当磁场方向与热通量方向一致时,磁场显著强化磁性液体的导热系数,其导热系数随磁场强度的增加而近似线性增加,且体积浓度越大增加量越大;当磁场方向与热通量方向垂直时,磁性液体的导热系数随磁场强度的变化不明显。     

Remote Field Eddy Current Control Using Rotating Magnetic Field Transducer: Application to Pressure Tubes Examination

The remote field eddy current (RFEC) technique is used to investigate the possibility of detecting the discontinuities practiced on pressure tubes samples from nuclear reactors, pressurized heavy water reactors (PHWR) type. In this article, we propose to develop the RFEC using the technique of rotating magnetic field (RMF). A method for calculating the field generated by the eddy current transducer with RMF using propagator matrix was developed. The experimental measurements are realized for artificial discontinuities practiced in pressure tubes samples.     

Determination of the Geomagnetic Field Induction from a Mobile Ferromagnetic Object

The solution of the problem of determining the induction of the geomagnetic field from a mobile ferromagnetic object by measuring the angular position of the object and the projections of the magnetic-induction vectors using two three-component magnetometric sensors is considered.     

Magnetic Field Design by Using Image Effect from Iron Shield

Permanent magnet rings are presented, which exploit the image effect in the surrounding circular iron shields. The theory is given for a general permanent ring when the magnetization orientation at each coordinate angle ψ changes by =(n+1)ψ, where n is a positive or negative integer. For the uniformly magnetized case n=-1, the permanent ring produces no field in its bore, and the field is that of a dipole outside. When the ring is surrounded by a soft iron shield, its field becomes uniform in the bore, and zero outside the ring. The field can be varied continuously by moving the iron shield along the magnet axis. A small variable field device was constructed by using NdFeB permanent rings, which produced a field flux density of 0-0.5 T in the central region.     

高精度智能磁场测量仪的设计

设计了一种由微处理器控制的具有通信接口的高精度智能磁场测量仪,通过双只配对的集成霍尔传感器来获取磁感应强度的信号,采用压频变换器完成数据的采集,并对仪器进行了校准和实验．实验结果表明,所设计的磁场测量仪在整个量程范围内的测量精度达到了0.1mT．该仪器不但可进行磁场的精密测量,还可用于对无线通讯基站电磁辐射的网络化远程监测．     

Method and Devices for Measuring Magnetic Field Parameters

A new method and devices are suggested for measuring constant, variable, or pulsed magnetic field parameters. The method involves transforming electromagnetic energy into elastic vibration energy in the presence of a magnetic field. This makes it possible to carry out measurements under complex conditions, for example at high temperature or with high intensity ionizing radiation.Translated from Izmeritel’naya Tekhnika, No. 3, pp. 35–38, March, 2005.     

三维磁场精密测量系统的研制

介绍了三维磁场精密测量系统的研制,利用差动方式连接的6个霍尔元件构成三维磁场传感器,通过压频变换器完成数据采集,并采用电压比测量法来补偿温度变化对霍尔元件输入电阻的影响．对系统进行了高精度的标定,消除了温度变化对霍尔元件灵敏度系数的影响．标定后的系统达到了0．5％的精度,并利用这一系统对高速磁悬浮列车的气隙磁场进行了测量．     

利用脉冲强磁场测量超导材料的HC2和JC（H）

提出了利用脉冲磁场对超导材料ＨＣ２和ＪＣ（Ｈ）的测量方案，并研制出了测试装置，对ＮｂＴｉ，Ｎｂ３Ｓｎ，Ｎｂ３Ｇｅ及掺ＴｉＮｂ３Ｓｎ等超导材料的ＨＣ２和（ＨＣ（Ｈ）进行了测量，得到了理想的测试结论和有益的测试经验。     

辽宁省重力场特征与矿产预测

以辽宁省重力场为研究对象,通过对草河掌一八里甸岩体的重力二维反演以及大台沟铁矿重磁场特征分析,论述了重力异常解释在推断成矿有利部位方面的方法技术应用,认为重力梯度带附近为多金属矿产成矿有利部位,重磁同源异常为“鞍山式”铁矿的成矿标志之一。     

隔声现场测量的扬声器声源法改进

通过对现行国家标准关于隔声现场测量中扬声器声源法的分析，提出扬声器声源多点放置隔声现场测量的改进方案。在扬声器声源多点测量方法中，合理选取不同角度放置声源，测得声波以不同角度入射时构件的隔声量，再对测试结果按照角度求平均值。实验结果表明，扬声器声源多点放置测得的结果能更好地反映隔声构件的现场隔声效果，且实验可重复性好，实验条件便于控制。     

Measurement of the Neutron Lifetime Using a Gravitational Trap and a Low-Temperature Fomblin Coating

We present a new value for the neutron lifetime of 878.5 ± 0.7_stat. ± 0.3_syst. This result differs from the world average value by 6.5 standard deviations and by 5.6 standard deviations from the previous most precise result. However, this new value for the neutron lifetime together with a β-asymmetry in neutron decay, A₀, of −0.1189(7) is in a good agreement with the Standard Model.     

Measurement of the input resistance of a rf biased SQUID

Measurements of the real part of the input impedance of a RF biased SQUID are described. The experimental data are in good agreement with the predictions of the recently published theory. In particular the dependence of the input resistance on the detuning of the rf bias frequency from tank circuit resonance frequency is confirmed.     

Direct Generation of Internse Compression Waves in Molten Metals by Using a High Static Magnetic Field and Their Application

Compression waves propagating through molten metals are contributed to degassing accelerating reaction rate,removing exclusions from molten metals and refining solidifcation structures during metallurgical processing of materials,In the present study ,two electromagnetic methods are proposed to generate intense compression waves directly in liquid metals.One is the simultaneous imposition of a high frequency electrical current filed and a static magnetic field ;the other is that of a high frequency magnetic field and a static magnetic field ,A mathematical model based on compressible fluid dynamics and electromagnetic fileds theory has been developed to derive pressure distri-butions of the generated waves in a metal.It shows that the intensity of compression waves is proportional to that of the high frequency electromagnetic force,And the frequency is the same as that of the imposed electromagnetic force,On the basis of theoretical analyses ,pressure change in liquid gallium was examined by a pressure transducer under various conditions.The observed results approximately agreed with the predictions derived from the theoretical analyses and calculations.Moreover,the effect of the generated waves on improvement of solidification structures was also examined .It shows that the generated compression waves can refine solidification structures when they were applied to solidification process of Sn-Pb alloy ,This study indicates a new method to generate compression waves by imposing high frequency electromagnetic force locally on molten metals and this kind of compression waves can probably overcome the difficulties when waves are excited by mechanical vibration in high temperature environments.     

基于无线测温的真空熔铸炉高温合金液相温场检测

以无线测温技术为基础,分析了感应加热式真空熔铸炉高温合金液相温场检测原理,提出了在高温合金材料精密铸造模型浇注(定向结晶)过程中,采用预埋敷设温度传感器组的液相温场跟踪检测方法,并对其进行了说明。     

Layered Superconductors in an External Magnetic Field

Presence of localized magnetic moments and inhomogeneites leads to an unconventional behavior of the upper critical field for layered superconductors. In addition, one can observe a large diamagnetic moment at H H _c2 and in the normal resistive state.     

Magnetic Field Stabilization for Magnetically Shielded Volumes by External Field Coils

For highly sensitive magnetic measurements, e.g., a measurement of the neutron electric dipole moment (EDM), the magnetic field has to be stable in time on a level below picoTesla. One of several measures we employ to achieve this uses an external field coil system which can stabilize the ambient external field at a predefined value. Here we report on the construction and characterization of such a system in the magnetic test facility at PSI. The system actively stabilizes the field along the axis of the EDM experiment by means of four coils in a Helmholtz-like configuration. Additional coils serve to compensate for transverse ambient field components. Because of the long integration times in the EDM experiment (about 100 s or more) only slow disturbances have to be corrected for. The performance of the system has been measured using static and moving magnetic sources and suppression factors in excess of 200 have been observed.     

Measurement of critical temperature as a function of field

The critical temperature has been measured for various magnet conductors as a function of the perpendicular applied magnetic field. The isothermal environment was provided by a variable temperature cryostat which fits into the bore of a 10 telsa solenoid. The temperature gradient across the sample volume was measured to be less than 25 millikelvins. The superconducting to normal state transition was measured resistively, using sample current densities from 0.01 to 2 A cm^?2. The maximum applied magnetic field was 10 T and varied less than 0.5% in the sample volume. The critical transport current range of the samples measured from tens to thousands of amperes in the presence of a 10 T perpendicular magnetic field at 4.2 K.