SDAT: analysis of <Superscript>131m</Superscript>Xe with <Superscript>133</Superscript>Xe interference

The Spectral Deconvolution Analysis Tool (SDAT) software was developed at The University of Texas at Austin. SDAT utilizes a standard spectrum technique for the analysis of β–γ coincidence spectra. Testing was performed on the software to compare the standard spectrum analysis technique with a region of interest (ROI) analysis technique. Experimentally produced standard spectra and sample data were produced at the Nuclear Engineering Teaching Laboratory (NETL) TRIGA reactor. The results of the testing showed that the standard spectrum technique had lower errors than the ROI analysis technique for samples with low counting statistics. In contrast, the ROI analysis technique outperformed the standard spectrum technique in high counting statistics samples. It was also shown that the standard spectrum technique benefitted from a compression of the number of channels within the spectra.     

多源光谱信息融合在水质分析中的应用

为解决现有单一光谱法用于水质有机污染综合指标分析精度较低的问题,提出一种基于多源光谱信息融合的水质分析新方法。本方法采用改进的参考独立成分分析方法分别提取紫外吸收光谱和三维荧光光谱对检测水样的多种有效信息特征,去除与水质分析无关的干扰信号;然后采用最小二乘支持向量机进行特征信息融合建模。采用总有机碳指标覆盖范围在3.4~125.3 mg/L内的32个城市地表水和生活污水样本为研究对象,对其紫外光谱、荧光光谱数据进行了信息融合分析实验。结果表明:采用融合分析方法后,对总有机碳指标的分析误差均方根比单一紫外光谱分析法和单一荧光光谱分析法分别下降36.1%和34.7%。     

基于多阶导数拉曼光谱组合技术的矿物油模式分类

为了实现对法庭科学领域重质矿物油物证的快速、准确、无损的鉴定,该文基于光谱分析技术提出了一种多阶导数光谱数据组合分析的方法。收集了80种不同型号、不同厂家的重质矿物油样本,利用傅里叶变换拉曼光谱分析法采集样本的原始光谱数据和导数光谱数据,并通过结合化学计量学构建分类模型。在构建的主成分分析(PCA)结合径向基函数神经网络(RBF)分类模型中,对单独的原始光谱、一阶导数谱和二阶导数谱数据的训练集准确率分别为80.0%、86.7%和86.2%,测试集准确率分别为73.3%、80.0%和72.7%;对组合后的原始光谱+一阶导数谱、原始光谱+二阶导数谱和一阶导数谱+二阶导数谱数据的分类中,训练集准确率分别为97.0%、96.7%和100%,测试集准确率分别为85.7%、90.0%和100%。结果表明,对组合后的导数光谱与原始光谱构建分类模型,准确率更高。其中,基于一阶导数谱+二阶导数谱数据构建的PCA结合RBF分类模型的结果最为理想,准确率达100%。而K最近邻算法模型由于受到样本不均匀的影响,整体分类准确率均较低。利用组合的导数光谱与原始光谱数据构建分类模型能够实现对重质矿物油样本的快速、准确、无损鉴别,可为光谱组合技术在法庭科学及其他分析测试领域的应用提供一定的借鉴和参考。     

4-(2-甲基-丁氧基)苯甲酰氧基-4′-苯甲酰氧基苯基卟啉的合成

四 (对羟基苯基 )卟啉 [Ｔ( 4 ＨＰ)Ｐ]具有共扼大π键及刚性平面 ,在 65 0ｎｍ左右产生纯的红色荧光 ,是一种较好的发光材料。依据 4 ( 2 甲基 丁氧基 )苯甲酚氧基 4′ 苯甲酰氧基苯基穴醚 [2 .2 ]具有液晶性[1 ] ,本文设计使Ｔ( 4 -ＨＰ)Ｐ的羟基进行酯化反应后生成的卟啉衍生物同时具有荧光和液晶性质 ,估计在发光材料特别是新近出现的圆偏光电致发光材料中具有潜在的应用[2 ] 。反应混合物通过柱色谱分离得到了酯化程度不同的几种卟啉衍生物。合成路线如下1　实验1 1　仪器及试剂Ｐｅｒｋｉｎ Ｅｌｍｅｒ1 70 0红外光谱仪 ,ＫＢｒ压…     

高效液相色谱-电喷雾质谱(HPLC-ESI-MS/MS)测定新型抗癌铂配合物

采用高效液相色谱-电喷雾-多级质谱法(HPLC-ESI-MS/MS), 研究了cis-3,5-diisopropylsalylic cyclohexanodiaminoplatinum(Ⅱ)的电喷雾质谱行为, 鉴定了其杂质, 并测定了其纯度.     

Computer analysis of complex gamma-ray spectra from semiconductor detectors

The problem of gamma-ray spectrum analysis is treated by combination of peak-searching, choosing the fitting intervals and fitting the line shape by a shape function. The performance of the program is examined by analysis of a test spectrum,^177mLu.     

A smoothing method for X-ray spectrum based on best beamforming

X-ray spectrum is widely used in the field of analysis and measurement. Due to the effect of electronic noise and statistical fluctuation of particle, the measurement spectrum is unsmoothed. In order to improve the signal-to-noise ratio of the spectrum, many smoothing methods were applied to process spectrum. The conventional smoothing algorithms regard the spectra as time series. In fact, X-ray spectrum is an angle series, and its essential is spatial spectrum. So the conventional smoothing algorithms are not fit for smoothing X-ray spectrum. In this paper, a new measuring model for X-ray spectrum is built up, and a new smoothing method based on best beam forming is proposed for X-ray spectrum. It regards the measured X-ray spectrum as the classic spectrum estimation result of array signal. The spatial spectrum is re-estimated to smooth the spectrum by best beam forming. The relationship between cross-correlation coefficient and number of array cell is applied to choose parameter q. The experimental results show that the method is effective to smooth X-ray spectrum with high resolution when q is larger than 200.     

PCGAP: Application to analyze gamma-ray pulse-height spectra on a personal computer under Windows NT®

PCGAP is a software code, which was written to provide gamma-ray pulse height spectrum analysis on a personal computer platform. The code was specifically developed for Windows NT for either an Intel^® or DEC Alpha^® based processor. PCGAP includes programs which can be used to control data collection using a Canberra INSPECTOR^® multichannel pulse-height analyzer. With suitable spectrum conversion routines PCGAP can be used to analyze data from almost any multi-channel analyzer. Besides the normal functions associated with a robust spectrum analysis package, PCGAP can be used for radionuclide analysis for actinides via L-X and gamma-ray spectrometry. It can be used to control and analyze data from an INEEL developed pulse injection system for individual spectrum validation. The package includes programs for the manual analysis of spectra using displays which permit the spectroscopist to interactively define the spectral continuum and peak fitting limits, and display the resulting function fitting forms.     

关于透光率导数光谱用作定量分析的可行性

探讨了我率导数光谱（d^nT/dλ^n）与吸光度导数光谱（d^nA/dλ^n）的关系，并讨论了用d^nT/dλ^n作定量分析的可行性及其产生分析误差的原因以及最佳测量条件。     

Experimental and theoretical vibrational study of bis(N,N-dimethylthiocarbamoylthio)acetic acid.

Harmonic vibrational analysis at HF/3-21G level is performed on the ab initio optimized molecular structure of bis(N,N-dimethylthiocarbamoylthio)acetic acid, and the outcome used in assigning the infrared spectrum of the acid. The calculated spectrum compares well with the experimental solid-state FT IR spectrum recorded at 298 and at 77 K.     

芳香环状聚酯二聚体的结构表征

通过基质辅助激光解析电离飞行时间质谱以及核磁共振技术对芳香环状聚酯二聚体的结构进行了表征.质谱分析结果发现除了目标化合物的质子化分子离子峰外,未出现更多的碎片峰,而核磁共振结果对芳香环状齐聚物的氢以及碳的位置给予了确认.从而为芳香环状齐聚物的结构分析提供了一种新的分析方法.     

Spectral line shape fitting in instrumental neutron activation analysis of pottery

The γ-ray spectrum of a neutron-activated clay standard is analyzed by spectral line shape fitting and the results are compared with an empirical analysis of the spectrum based on detector calibrations. It is concluded that trace element analysis of pottery may be simplified and enhanced by a combination of spectral line shape fitting and detector calibrations.     

Dioxidobutane: A comparison between high field and Eu-shifted PMR spectra

Complete analysis of the high field spectrum of the title compound gives well determined parameters in all cases; the value of the CH? CH coupling is in agreement with free rotation around this bond. In contrast, the Eu-shifted spectrum does not allow such a complete analysis because of lack of resolution. Shift dependence on concentration and temperature is reported and discussed.     

Application of simulated standard spectra for the analysis of complex sample spectra from NaI(Tl) detectors

The most accurate method for the analysis of complex gamma ray spectra from scintillation detectors is least squares method. The major requirement of this method is individual standard spectra of all nuclides expected in the complex spectrum which is not possible and feasible for some nuclides. In the present work, an approach of using simulated standard spectrum of the radionuclides for the least squares analysis is studied. The paper describes the methodology used for the generation of simulated spectrum which is the main objective, and validation of results using standard sources in the Sodium Iodide (NaI(Tl)) based gamma ray spectrometer.     

A spectrum stripping method for the computer-coupled activation analysis of unknown samples by γ-ray spectrometry

A spectrum stripping method for the computer-coupled activation analysis of unknown samples using γ-ray spectrometry is discussed. Before the unscrambling of the γ-ray is performed using standard spectra of the components, each spectrum is smoothed, statistically weighted and corrected for background. The photopeaks of the standard spectra are then aligned with the respective peaks of the sample spectrum, one at a time after correcting for gain drift if necessary, and the undesired components are stripped out. After successive subtraction, the characteristic spectrum of the desired element is compared with that of the standard to determine its weight. The results obtained using the present method are as good as those obtained from least-squares analysis in ideal cases, but appear to be better when assumptions inherent in the least-squares method are no longer valid.     

定量能谱CT多参数成像诊断多发性骨髓瘤价值及临床意义

本文探讨能谱CT多参数成像定量分析对多发性骨髓瘤(MM)的诊断价值及与实验室指标、疾病分期的关系。选取MM患者62例作为研究组,另随机选取同期健康者62例作为对照组,均行能谱CT检查。结果发现,研究组40 keV、50 keV、60 keV、70 keV、80 keV、90 keV、100 keV能量水平的CT值、能谱曲线斜率均低于对照组(P<0.05);上述能量水平的CT值、能谱曲线斜率联合诊断的AUC为0.875;40~100 keV能量水平的CT值、能谱曲线斜率与Hb呈正相关,与CREA、BUN、β2-MG、疾病分期呈负相关(P<0.05)。因此能谱CT多参数成像定量分析在MM诊断方面具有较高价值,且与患者Hb、CREA、BUN、β2-MG水平、疾病分期密切相关。     

壳聚糖固定化N-亚水杨基甘氨酸锌Schiff碱配合物的研究

利用天然高分子聚合物壳聚糖的轴向配位能力, 首次合成了壳聚糖-N-亚水杨基甘氨酸Schiff碱锌配合物, 通过元素分析、紫外吸收光谱、红外吸收光谱和热分析等方法对配体及配合物进行了表征, 推测了配合物的结构组成. 以Pyrogallol-NBT比色法测定了合成配合物对超氧阴离子自由基的清除能力. 结果表明, 壳聚糖固定化N-亚水杨基甘氨酸锌Schiff配合物对超氧阴离子自由基的清除能力与水杨醛锌Schiff配合物相比大致一样, 但毒性较小.     

Doppler-broadened boron peak analysis by using a modified spectral decomposition algorithm

Doppler broadening of a 477.6 keV line combined with a recoil of an excited Li nucleus is the characteristic of PGAA, which leads to complicated gamma-ray spectrum which is difficult to analyze. For this solution, a modified algorithm for an automated analysis of the Doppler-broadened peak spectrum is presented. The modified algorithm maintained the consistency of a Doppler-broadened peak with the finest analysis algorithm used for a Gaussian gamma-ray peak analysis in the HYPERMET code.     

邻香草醛缩天冬氨酸铜、锌、钴、镍配合物的合成

氨基酸希夫碱是具有多种配位原子和生物、化学活性的配体,其过渡金属配合物对生物无机化学和医药有重要意义［１～３］,我们曾报道过某些氨基酸希夫碱及其配合物的抗Ｏ－·２性能［４,５］．本文合成了邻香草醛缩天冬氨酸铜、锌、钴、镍配合物并进行了系列表征,提出其...     

硒的形态分析进展

对近年来有关硒的形态分析的发展作了综述,对新的分离方法如色谱法、氢化物发生法、毛细管电泳和新的检测技术如电感耦合等离子体质谱、原子光谱给予较多的关注。