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.     

核探测器的进展

本文介绍了几种基本核探测器的国外最新进展。     

CONCENTRATION POLARIZATION ANALYSIS AT THE ENTRANCE REGION OF A FLAT SHEET PERVAPORATION MODULE FOR VOC REMOVAL

Concentration polarization is a phenomenon that is inherent in all membrane separation processes, which is difficult if not impossible to measure experimentally. Concentration polarization in a pervaporation module causes flux decline and is therefore an important issue in predicting the performance of the membrane unit for evaluation and optimization. Short-form (small L/D ratio) membrane configurations, commonly used for membrane evaluations or certain material separations, compound the complexity of process modeling that addresses concentration polarization since a substantial portion of the membrane flow channel would be considered as an “entrance region” based on the flow profile that is not fully developed. This article employed the classic boundary layer theory, combined with mass transfer phenomena in a pervaporation process that is used in volatile organic compound (VOC) removal from contaminated water sources, to theoretically analyze the concentration polarization severity in the entrance region of a flat sheet membrane module.     

基于电容读出的非制冷红外探测器

介绍了一种基于标准硅工艺的电容读出式微悬臂梁非制冷红外探测器的设计、制作以及集成读出电路的设计。该探测器用于探测室温下物体的红外辐射，其响应波长为8～12 μm 。由于氮化硅和铝的热膨胀系数相差很大，用这两种材料的薄膜做成的双材料微悬臂梁在红外辐射下会发生弯曲，微悬臂梁和衬底形成一个可变电容，通过检测电容的变化来反映微悬臂梁的弯曲，从而可以探测红外辐射的情况。采用和探测器集成的CMOS读出电路对探测器信号进行读取，微悬臂梁的电容灵敏度可达2.5 fF/K，温度分辨率为0.1 K。     

选择适用原理的气体探测器

气体探测器是当有气体泄露或危险将要发生时,提醒有关人员采取相关措施以预防事故发生,介绍了如何正确地使用气体探测器。     

Position Adaptive Measurement Model for Double-four Quadrant Photoelectric Detector

A modeling method of the support vector machine combined with matrix optics is considered; a complete new measurement model for double-four quadrant photoelectric detector is built. According to the analysis of the received light spot size and its motion with the changes of the defocusing amount of detector photosensitive surface and the detector position attitude in the optical path, a mathematic expression of photoelectrical conversion is given, which can be applicable to random setting position of the detector at any time. Based on least square support vector machine （LS SVM）, the mapping relationship among the output signal linear characteristic parameters （zero neighborhood gradient and intercept）, the defocusing amount of the detector and the installation position attitude angle is established. Thus, the multiple dimensional high accuracy measuring and adjusting control system can be left out, and adaptive measurement of the detector parameters can be realized. Compared with existed measurement model and method, the presented model has the advantages of more clear physical meaning, closer to work mechanism of detector, acquiring more complete sample data and wiping out the dead spots or bad spots in measurement. And the accuracy of displacement measurement is increased to 3μm. At the same time, this measurement mode provides a technical shortcut for three-dimensional small angle measurement.     

金属结构红外探测器振动噪声的研究

为使红外探测器在振动干扰的环境下仍具有足够高的探测率,必须降低其因振动而产生的噪声幅度.控制探测器振动噪声的主要手段之一是控制其机械振动幅度,尤其是共振振幅.采用锤击法,利用冲击激励的宽频特性,研究了金属结构红外探测器的共振特性及影响振动噪声的力学因素.通过改变探测器结构的动力学特性,探寻了减振降噪的几种途径.实验结果表明,探测器悬臂冷指的结构参数对探测器的振动特性起主要作用.在冷指自由端与壳体间填胶做支撑、或冷指固定端与壳体间用胶粘隔振的减振降噪效果最好,可使振动噪声降至原值的1/20.     

Control of very-long-wavelength infrared HgCdTe detector-cutoff wavelength

Hg_1-xCd_xTe is an important material for infrared (IR) detection applications where the bandgap of the alloy varies from semimetal to 1.4 eV. The large variation in bandgap energy with HgCdTe composition causes difficulty in controlling detector-cutoff wavelength, particularly for the long-wavelength IR and very-long-wavelength infrared (VLWIR, greater than 12 μm) spectral bands. Our ability to control the HgCdTe composition and compositional profile during growth by molecular beam epitaxy (MBE) is improved significantly by using automated feedback control from spectroscopic ellipsometry (SE) measurements, where the standard deviation in the error in composition has improved by a factor of 5, from σ=0.0081 to σ=0.0016. To improve our ability to predict cutoff wavelength from IR transmission measurements, we have used a model of the absorption in HgCdTe to revise our past empirical cutoff relationship to include the effect of compositional grading. We have achieved a mean detector-cutoff wavelength of 14.1 μm and standard deviation of σ=0.25 μm for a series of 19 processed layers with a target cutoff of 14 μm. The excellent control in VLWIR detector cutoff we have observed is attributed to automated compositional control and an improved cutoff-prediction model.     

Markovian场中四能级系统的窄带五阶非线性效应

本文采用高阶相干函数理论研究了四能级系统在Markovian场下的窄带五阶非线性效应（NFPBFMS）。我们得到了混沌场模型、相散场模型及实高斯场模型下窄带拍频信号强度随时间的变化规律，并讨论了三种模型对测量原子能级分裂精度的影响。     

As离子注入碲镉汞的p+n结红外探测器

讨论了制作pn结构的另一种途径，即在n型HgCdTe材料上离子注入As^ 。然后通过辐射快速退火形成反型p^ 层来获得p^ n结。通过对制作工艺及实验结果的讨论，阐述了两种制作pn结工艺的特点，实验表明，采用辐射快速退火工艺可以在短时间内完成对HgCdTe注入表面的缺陷退火和杂质激活，而不会改变HgCdTe组份，已用此方法在注入As^ 的n型HgCdTe样片上制作出性能较好的p^ n结光伏红外探测器。