激光光散射仪及应用

介绍激光光散射仪的测定原理,常用测定仪器、测定方法以及在聚合物研究中的实际应用。     

基于51单片机的透光式孔洞检测仪设计

工业生产板带过程中,由于原料不稳定、工艺控制波动和设备异常等因素,会引入多种缺陷,孔洞属于引入的典型的严重缺陷。该文设计的孔洞检测仪相对于人工检测和影像检查具有检测精度高,投入成本低,易于现场安装和维护等多种优点,有很好的应用前景。     

Differential capacitance sensor as position detector for a magnetic suspension densimeter

A differential capacitance sensor has been used in the servosystem of a magnetic suspension densimeter to detect the position of a magnetic buoy. This type of sensor has not previously been used in this application. Its design, performance, and advantages are described.     

The effect of detector size on the signal-to-noise ratio in confocal polarized light microscopy

We introduce a signal-to-noise ratio in an attempt to suggest an optimum pinhole size for confocal polarized light microscopes. We find that pinhole sizes which are typically 60% greater than those used in nonpolarized light confocal microscopy are appropriate.     

Wire GEM detector

A wire GEM (WGEM) detector with a gas gap between meshes was constructed. The detector provides the amplification 5 × 10⁴ for the gas mixture of Ar + 20% CO₂ at atmospheric pressure. As compared with well-known GEM detectors produced by perforation the plastic plate metallized on both sides the WGEM does not suffer from breakdowns between its electrodes and the effect of accumulation of charges on holes’ walls is absent. As a result the WGEM has high reliability and stability.     

The photomultiplier tubes in the light sensor of an orbital detector for studying the fluorescent radiation of extensive air showers

The characteristics of the photomultiplier tube used in a photodetector of fluorescent radiation and the arrangement of its power supply and control systems are described. The photodetector is used to observe extensive air showers from near-Earth orbit under varying conditions of the night sky background.Translated from Pribory i Tekhnika Eksperimenta, No. 1, 2005, pp. 108–111.Original Russian Text Copyright © 2004 by Garipov, Khrenov, Lubsandorzhiev, Belyanchenko, Smolitskiy, Salazar, Fokitis.     

基于STM32的手持式地震波检波器测试仪研制

针对国内外产品优点和克服缺点的基础上,通过研究地震波检波器测试仪所基于的测量原理,引入了STM32F10X和带触摸屏的液晶显示器,设计出了功耗小、便于携带、存储容量大、工作稳定,能够及时准确测量地震波检波器是否处于正常工作状态的地震波检波器测试仪。     

一种新的鲁棒恒虚警检测器

本文基于自动删除单元平均(ACCA)方法和单元平均(CA)方法,提出了一种新的恒虚警检测器(ACGCA-CFAR)以提高CFAR检测的抗干扰性能.它的前沿和后沿滑窗分别采用ACCA和CA方法产生两个局部估计,然后取最大值作为背景噪声功率水平估计.在SwerlingII型目标假设下,推导出ACGCA在均匀背景下虚警概率Pfa的解析表达式,并与现有方案进行了比较,仿真和试验数据处理结果表明:ACGCA-CFAR在均匀背景和非均匀背景下均具有相当好的检测性能,而它的样本排序时间只有OS和ACCA的1/4.     

Absolute beam brightness detector

In generally accepted emittance measurement, main attention is concentrated on emittance areas ?(x), ?(y) occupied by desired part of ion beam in transverse phase space and shape of these areas. The absolute beam phase density (brightness) as usually is not measured directly and the average beam brightness B is calculated from a beam intensity I and the transverse emittances. In the ion source and low energy beam transport (LEBT) optimization, it is important to preserve the beam brightness because some aberration of ion optic and beam instabilities can decrease the brightness of the central part of ion beam significantly. For these brightness measurements, it is convenient to use an absolute beam brightness detector with the brightness determination from one short considered in this article.     

A multielectrode X-ray detector

A multielectrode vacuum photoemission detector for X-ray tomography of plasmas at the ITER facility is described. The detector characteristics have been investigated with an X-ray source. The spectral response of the detector to X-ray photons with energies of 3–30 keV has been determined. The spatial and angular dependences of the X-ray detection efficiency are presented. The useful signal of the ITER facility has been estimated.     

便携数字式超声探伤仪

介绍了超声检测在起重运输机械中的应用,在分析超声波探伤原理的基础上,提出超声波探伤系统的硬件和软件设计方法.该系统用于起重运输以及其相关的行业,是安全作业和运行的有力保障.经过长时间的运行,证实系统工作稳定、性能良好.     

高效液相色谱法-蒸发光散射检测器结合化学计量学方法测定硫酸卡那霉素注射液中卡那霉素A

将高效液相色谱法-蒸发光散射检测器和化学计量学方法结合起来,建立了一种新的测定硫酸卡那霉素注射液中卡那霉素A含量的方法。考察了流动相的种类、比例以及检测器的条件等对测定的影响。实验确定的色谱条件为：C18色谱柱（200mm×4．6mm,5μm）;流动相为甲醇：水（50：50）;蒸发光散射检测器;漂移管温度50℃;增益50。实验结果表明,该方法的RSD为6．5％。根据经化学计量学方法处理后的图谱计算样品中卡那霉素A的含量为0．08g／mL。     

Dangerous-electricity annunciator and detector.

Investigations into electrical accidents in hospitals have shown that the hazards are usually associated with the simultaneous use of two or more instruments. Recognizing this, several groups have written safety standards which limit the allowable potential difference between any two conductors near or connected to the patient. Implementing such a standard may be difficult since there may be a large number of such conductors and they must be tested using all combinations of two conductors. A simple scanning circuit using programmable operational amplifiers (PRAMs) and MOS digital circuitry makes the series of safety checks quickly and efficiently. The design includes both the ability to detect dangerous conditions and a digital annunciator to indicate which of the many leads being checked simultaneously is at fault. The scanning rate is rapid enough to allow the detection of dangerous transients. Preliminary results indicate that this portable, battery operated device is useful in providing an electrically safe environment for patients.     

Microfabricated high-throughput electronic particle detector

We describe the design, fabrication, and use of a radio frequency reflectometer integrated with a microfluidic system, applied to the very high-throughput measurement of micron-scale particles, passing in a microfluidic channel through the sensor region. The device operates as a microfabricated Coulter counter [U.S. Patent No. 2656508 (1953)], similar to a design we have described previously, but here with significantly improved electrode geometry as well as including electronic tuning of the reflectometer; the two improvements yielding an improvement by more than a factor of 10 in the signal to noise and in the diametric discrimination of single particles. We demonstrate the high-throughput discrimination of polystyrene beads with diameters in the 4-10 microm range, achieving diametric resolutions comparable to the intrinsic spread of diameters in the bead distribution, at rates in excess of 15 x 10(6) beads/h.     

In-tube demagnetizing pig flaw detector

A method of in-tube demagnetization that can be realized using a demagnetizing magnetic plunger that passes through a tube and is driven by a transported product has been developed as a result of analysis of qualitative and quantitative characteristics of the demagnetization process.     

A measuring square-law diode detector

A general approach, circuit diagrams, and test results of a square-law detector with improved metrological characteristics are presented. The detector is based on a “diode + current-to-voltage converter” scheme. The measured characteristics are as follows: the dynamic range is 40 dB, and quadraticity factor is 2.00 ± 0.05. The working frequency band of a particular detector is from 0.001 to 2 GHz. The proposed approach is suitable for detectors of most kinds (series, parallel, single- and two-cycle, etc.), operating in the radio frequency band.     

Trigger of the KEDR detector

The primary and secondary triggers of the KEDR detector operating at the VEPP-4M electron-positron collider of the Budker Institute of Nuclear Physics since 2000 are considered. The detector systems generating the signals, the design of the triggers, the timing characteristics of their operation, and their communication with the data acquisition system are described. The average rates of triggering of the primary and secondary triggers are 3.5 kHz and 50 Hz, respectively. The total efficiency of the data acquisition system and the triggers is 91.45%, and the efficiency of event selection is 98%. A number of results of world importance have been obtained using the KEDR detector. In particular, the masses of J/_{ψ, ψ}”, and _ψ(3770) mesons and a τ lepton have been measured in the experiments with the KEDR detector with accuracies surpassing the values attained worldwide.     

带前置放大器的热导检测器

在通用型热导检测器直流电桥的基础上 ,增加了内含倍乘× 1、× 2、× 4、× 8的前置放大器 ,使检测器的灵敏度达到 12 0 0 0 m V· m L /mg,比不加前置放大器的热导检测器的灵敏度提高了 4～ 5倍 ,已成功地应用在商品化 GC- 80 0 0 N气相气色谱仪上