离子迁移谱在环境污染物检测中的应用

目前对环境污染物的检测手段有多种,但都存在一定的局限性,作者介绍了一种环境污染气体检测的新方法—离子迁移谱(IMS)法.结合本实验室的研究工作简述了设计制作IMS的基本结构,介绍了IMS的基本原理,阐述了近期国际上IMS在环境污染物(如苯系物、卤代烯烃、全氟化碳、醇类及多环芳香烃等)检测中的研究进展,最后通过对研究结果进行分析,得出IMS在环境污染物检测这一领域中正逐步吸引越来越多的科学家的兴趣,是一种非常有效的环境检测方法,具有重要的应用价值和发展前景.     

离子迁移谱在生物医学中的应用介绍

概述了离子迁移谱的特点及其工作原理,给出了离子迁移谱技术应用领域,并对该技术在生物医学领域中的应用及其最新进展进行了阐述,最后通过对研究结果进行分析,得出结论:离子迁移谱在生物医学这一领域正逐步吸引越来越多的科学家的兴趣,具有重要的应用价值和发展前景。     

CCD在光谱分析系统中的应用研究

本文对利用ＣＣＤ作传感器件进行光谱分析的方法进行了理论和实验研究。通过分析ＣＣＤ的结构特点和光电特性，从理论上证明了利用ＣＣＤ进行光谱分析的可行性，设计了一套适合线阵ＣＣＤ的高速图像采集卡，建立了一套智能化光谱数据采集分析系统。该系统主要由光栅、ＣＣＤ传感器及数据采集卡、计算机等部分组成。我们用高压汞灯作为标准光谱进行定标，得到了一个非常简单的计算光谱的数学公式。实验表明该系统具有较高的测量精度，特别适用于瞬态过程的光谱分析。     

Penning阱中离子谱的优化及Hn^＋离子的分析

根据Penning阱存储离子的探测原理,系统分析了阱内离子信号及信号本身的噪声、实验仪器及探测电路的噪声干扰,采用适当的品质因数和电子束流,得到较高信噪比和分辨率的离子谱.并对Hn+离子的形成机制和结构进行了分析.     

基于光纤传感的化学需氧量全光谱检测系统

为了快速准确地检测地表水、污水的化学需氧量(COD),设计了一种十字通透式结构光纤传感器,建立了一种水质COD全光谱检测系统。基于该系统,建立了COD与光谱吸光度的相关性数学模型。对配置的检测水样进行了测量,并比较哈希DR 6000多参数水质检测仪对相同水样测量得到的数据,可以发现,所构建的系统与哈希DR 6000多参数水质检测仪测量COD的示值误差小于3%,能较好的适用于水质COD实时在线检测。     

Anomalous positive ion mobility in liquid 3He

Measurements of the mobility μ₊ of positive ions in liquid ³He under a pressure of 1 bar in the temperature range 0.05 < T < 0.6K exhibit a sharp peak in μ₊(T) near 0.2K and irreproducible behaviour at lower temperatures.     

一种光谱偏振成像系统设计及应用

为了获取目标和背景的偏振信息,提高地面目标识别的准确度,提出一种光谱偏振成像探测系统。该系统采用旋转偏振片的方式对入射光的偏振状态进行调制,通过旋转滤光片进行光谱选择,从而实现光谱偏振成像探测。通过对该系统偏振度的探测精度进行实验测试,结果表明,所设计的光谱偏振成像探测系统达到4%的探测精度。利用该系统对地物背景中的迷彩伪装板进行了探测实验,分析所得的偏振度图像发现,目标在背景中较为明显,与草地及土壤背景区域偏振度的差值分别达到0.292和0.283。     

光电离-离子迁移谱快速监测一次性医疗器械中的环己酮

聚氯乙烯制成的一次性医疗器械在生产加工过程中,常使用环己酮作为部件粘结剂。由于残留的环己酮可释放到医疗器械管道和储存的溶液中,并可能对病人产生一定的副作用,因此,医疗器械中环己酮的快速检测日显重要。利用自主研制的紫外光电离-离子迁移谱装置对环己酮进行检测,检测限为15ppb,检测线性动态范围达到三个数量级。分别对三个品牌一次性输液器包装中的气体进行迁移谱测量,获得包装内环己酮的平均浓度分别为16.78,17.59和46.69ppm。该方法可以用于一次性医疗器械中环己酮等有机溶剂的快速检测,进行医疗器械产品的质量监控。     

Gaseous ion mobility and diffusion in electric fields of arbitrary strength

In a previous paper we presented the first kinetic theory of gaseous ion mobility which is valid for electric fields of arbitrary strength and for arbitrary ion-neutral interaction potentials and mass ratios. In this paper we extend this theory to gaseous ion diffusion and systematize it so as to greatly decrease the effort involved in computing high approximations to the transport coefficients. Analytical results in low approximation are discussed, as are scaling rules for ion mobilities and diffusion coefficients. An extensive study of the convergence of the successive approximations of this theory is given for model systems, from which it is concluded that the theory is accurate, particularly in third and higher approximation, when applied to ion mobility and mean kinetic energy. When applied to diffusion, the theory is less successful in some circumstances, but it is still the best general theory currently available.     

Mass exponent spectrum analysis of human ECG signals and its application to complexity detection

The complexity of electrocardiogram (ECG) signal may reflect the physiological function and healthy status of the heart. In this paper, we introduced two novel intermediate parameters of multifractality, the mass exponent spectrum curvature and area, to characterize the nonlinear complexity of ECG signal. These indicators express the nonlinear superposition of the discrepancies of singularity strengths from all the adjacent points of the spectrum curve and thus overall subsets of original fractal structure. The evaluation of binomial multifractal sets validated these two variables were entirely effective in exploring the complexity of this time series. We then studied the ECG mass exponent spectra taken from the cohorts of healthy, ischemia and myocardial infarction (MI) sufferer based on a large sets of 12 leads’ recordings, and took the statistical averages among each crowd. Experimental results suggest the two values from healthy ECG are apparently larger than those from the heart diseased. While the values from ECG of MI sufferer are much smaller than those from the other two groups. As for the ischemia sufferer, they are almost of moderate magnitude. Afterward, we compared these new indicators with the nonlinear parameters of singularity spectrum. The classification indexes and results of total separating ratios (TSR, defined in the paper) both indicated that our method could achieve a better effect. These conclusions may be of some values in early diagnoses and clinical applications.