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应用同步辐射X近边吸收谱法研究大气超细颗粒物中氯形态 被引量:3
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作者 张博 郎春燕 +7 位作者 马玲玲 杨国胜 龚仓 郑雷 马陈燕 赵屹东 胡天斗 徐殿斗 《分析化学》 SCIE EI CAS CSCD 北大核心 2013年第4期580-584,共5页
建立了X射线近边吸收光谱法(1sXANES)测定大气颗粒物中无机氯和有机氯形态及含量的分析方法及质量控制体系。在储存环能量为1.5 GeV和光子能量为2.82 keV条件下,利用束流强度在300~150 mA的同步辐射光激发分析无机氯、链烃代有机氯和... 建立了X射线近边吸收光谱法(1sXANES)测定大气颗粒物中无机氯和有机氯形态及含量的分析方法及质量控制体系。在储存环能量为1.5 GeV和光子能量为2.82 keV条件下,利用束流强度在300~150 mA的同步辐射光激发分析无机氯、链烃代有机氯和芳香烃代有机氯标准样品以及≤0.2μm的大气颗粒物样品。通过对标准品谱图的拟合计算,得到该方法无机氯、链烃代有机氯和芳香烃代有机氯最低检出限,分别为5.4,8.7和1.7μg/g。对已知无机氯和有机氯浓度的试样检出率均达到或接近95%,重复测定3-氯丙酸标准品(n=6),得到本方法的相对标准偏差(RSD)为0.9%。应用本方法可以实现定量无损地测定微量样品中氯的形态和含量,对城市大气颗粒物中氯的测定发现,颗粒物中无机氯和芳香烃代有机氯含量分别为110和12 ng/m3,链烃代氯的含量低于检出限。应用本方法对北京某地区大气颗粒物中氯元素形态进行测定,确定氯的主要存在形式是无机氯和芳香烃氯。 展开更多
关键词 氯形态 有机氯污染物 x射线近边吸收光谱 大气颗粒物
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Prediction of XRF analyzers error for elements on-line assaying using Kalman Filter 被引量:3
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作者 Nakhaei F Sam A +1 位作者 Mosavi MR Nakhaei A 《International Journal of Mining Science and Technology》 SCIE EI 2012年第4期595-601,共7页
Determination of chemical elements assay plays an important role in mineral processing operations.This factor is used to control process accuracy,recovery calculation and plant profitability.The new assaying methods i... Determination of chemical elements assay plays an important role in mineral processing operations.This factor is used to control process accuracy,recovery calculation and plant profitability.The new assaying methods including chemical methods,X-ray fluorescence and atomic absorption spectrometry are advanced and accurate.However,in some applications,such as on-line assaying process,high accuracy is required.In this paper,an algorithm based on Kalman Filter is presented to predict on-line XRF errors.This research has been carried out on the basis of based the industrial real data collection for evaluating the performance of the presented algorithm.The measurements and analysis for this study were conducted at the Sarcheshmeh Copper Concentrator Plant located in Iran.The quality of the obtained results was very satisfied;so that the RMS errors of prediction obtained for Cu and Mo grade assaying errors in rougher feed were less than 0.039 and 0.002 and in final flotation concentration less than 0.58 and 0.074,respectively.The results indicate that the mentioned method is quite accurate to reduce the on-line XRF errors measurement. 展开更多
关键词 PredictionAccuracyx-ray fluorescence Kalman FilterAssayingError
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Preparations of Complex Bimetallic Oxides from Bimetallic Assemblies Containing Different Copper(Ⅱ) Precursors and Comparison of Some Related Systems
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作者 Masaki Kobayashi Satoshi Ehara Naoshi Hayashi Satoru Sonoki Takashiro Akitsu 《Journal of Chemistry and Chemical Engineering》 2014年第7期647-653,共7页
This is a mini-review-like article including our recent results and methods for (new) metal oxides and (previously reported) composite materials composed of metal complexes and metal oxides for comparison to enhan... This is a mini-review-like article including our recent results and methods for (new) metal oxides and (previously reported) composite materials composed of metal complexes and metal oxides for comparison to enhance anisotropic structural changes intentionally. Some complex inorganic oxides are known that they may be promising color materials (absorbing visible light of certain wavelengths region) having potential application for environmentally benign catalysts, for example, photocatalysts. Chiral copper(Ⅱ) complexes having bidentate amine ligands ([CuL2]2+) can be acted as cationic building blocks of bimetallic metal complexes. We have prepared some chiral bimetallic complexes with various anionic metal complexes such as [PtCl4]2-, [M02O7]2 and Mn12 clusters (typical single-molecule magnets) which characterized by means of solid-state electronic and CD (circular dichroism) spectra, IR (infrared) spectra, synchrotron XRD (X-ray diffraction) and XAS (soft X-ray absorption spectroscopy). By sintering these precursor chiral bimetallic complexes, we have prepared complex inorganic oxides from them. The IR spectra indicated substituting metal-ligand bonds and losing organic moieties. The XRD pattern indicated complete changes of crystal structures. The XAS revealed replacing coordination atoms as well as oxidation of valences of metal ions. Furthermore, we will also investigate possibility of patterning by homogeneous precipitation method as bimetallic complexes to prepare desirable complex inorganic oxides. 展开更多
关键词 Metal oxides metal complexes xRD structural changes anisotropy.
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毒品检测方法的技术分类 被引量:1
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作者 方正 詹燮峰 +5 位作者 陈银彬 钟易晟 李永明 陆冠桥 徐和钼 李顺仁 《中国药物滥用防治杂志》 CAS 2024年第1期5-9,14,共6页
毒品是指鸦片、海洛因、甲基苯丙胺(冰毒)等以及国家规定管制的其他能够使人形成瘾癖的麻醉药品和精神药品。除了传统毒品犯罪,近年来新型毒品层出不穷,导致新型毒品犯罪比例逐渐上升,这对毒品检测技术的灵敏度、准确率、安全性、透视... 毒品是指鸦片、海洛因、甲基苯丙胺(冰毒)等以及国家规定管制的其他能够使人形成瘾癖的麻醉药品和精神药品。除了传统毒品犯罪,近年来新型毒品层出不穷,导致新型毒品犯罪比例逐渐上升,这对毒品检测技术的灵敏度、准确率、安全性、透视性等指标都有了更高的要求。本文概述了毒品的分类和危害、常见毒品的化学式以及新型毒品,同时介绍了广泛应用的毒品检测技术的优缺点及基本原理,包括光谱法、免疫法、毛细管电泳分析法和离子迁移谱法等。此外,本文还展望了X射线吸收光谱无损检测技术在毒品检测方面的潜力,介绍了X射线吸收光谱在塑料分类中的应用,以期探索毒品快速无损检测的新方法。 展开更多
关键词 毒品分类 毒品检测技术 新型毒品 x射线吸收光谱法
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骨性Ⅲ类错患者上气道生长发育的特点 被引量:8
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作者 祁祎喆 张亚秋 +1 位作者 刘珂 李永明 《中国组织工程研究》 CAS 北大核心 2017年第8期1209-1214,共6页
背景:很多研究表明骨性Ⅱ类错与上气道的形态存在一定的关系,但未见关于骨性Ⅲ类患者上气道生长发育及其与颅面部形态结构之间关系的相关研究。目的:基于颈椎骨龄定量分期法,探讨骨性Ⅲ类错畸形患者上气道生长发育的特点,为不同骨... 背景:很多研究表明骨性Ⅱ类错与上气道的形态存在一定的关系,但未见关于骨性Ⅲ类患者上气道生长发育及其与颅面部形态结构之间关系的相关研究。目的:基于颈椎骨龄定量分期法,探讨骨性Ⅲ类错畸形患者上气道生长发育的特点,为不同骨龄上气道参考值的建立和颅面部生长发育的研究提供一定的参考。方法:将收集的368例骨性Ⅲ类错畸形患者(4-39岁)根据颈椎骨龄定量分期法分为4期:Ⅰ期(加速期)、Ⅱ期(高峰期)、Ⅲ期(减速期)、Ⅳ期(结束期),对其X射线头颅侧位片进行测量,并对上气道矢状径的测量值进行分析。结果与结论:Ⅰ期各水平测量值无显著性别差异,Ⅱ、Ⅲ、Ⅳ期上气道各段除会厌谷与下咽壁点的距离外也无性别差异。从Ⅰ期到Ⅲ期,男性上气道后鼻棘点与咽顶点的距离、后鼻棘点与过后鼻棘点做蝶鞍点-颅底点连线的垂线与咽后壁的交点的距离、会厌谷与下咽壁点的距离有显著增长,过后鼻棘点-悬雍垂尖连线的中点做下颌角点-下齿槽座点连线的平行线与软腭的交点与过后鼻棘点-悬雍垂尖连线的中点做下颌角点-下齿槽座点连线的平行线与咽后壁的交点的距离、悬雍垂尖与中咽壁点的距离、下颌角点-下齿槽座点连线与舌根部的交点和下颌角点-下齿槽座点连线的延长线与咽后壁的交点的距离从Ⅱ期开始逐渐增大,后鼻棘点与上咽壁点的距离在Ⅰ期到Ⅱ期增长显著;从Ⅰ期到Ⅲ期,女性上气道后鼻棘点与咽顶点的距离、后鼻棘点与过后鼻棘点做蝶鞍点-颅底点连线的垂线与咽后壁的交点的距离显著增长,过后鼻棘点-悬雍垂尖连线的中点做下颌角点-下齿槽座点连线的平行线与软腭的交点与过后鼻棘点-悬雍垂尖连线的中点做下颌角点-下齿槽座点连线的平行线与咽后壁的交点的距离、悬雍垂尖与中咽壁点的距离、下颌角点-下齿槽座点连线与舌根部的交点和下颌角点-下齿槽座点连线的延长线与咽后壁的交点的距离、会厌谷与下咽壁点的距离从Ⅱ期开始逐渐增大,后鼻棘点与上咽壁点的距离在Ⅰ期到Ⅱ期增长显著;从Ⅲ期到Ⅳ期,各测量值基本无变化。上气道矢状径与颅颌面结构存在相关性。垂直骨面型对上气道口咽、喉咽水平有影响。提示骨性Ⅲ类错患者上气道与颅颌面部生长发育相关,并为骨性Ⅲ类错的发生与上气道关系的研究提供了实验依据。 展开更多
关键词 年龄测定 骨骼 x射线吸收光谱法 组织工程 组织构建 骨性Ⅲ类 错 颈椎骨龄定量分期 上气道 生长发育 垂直骨面型 颅颌面结构 国家自然科学基金
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Electronic Characterization of the Single-wall CarbonNanotubes: A XANES Study
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作者 WuZ.Y. HuT.D. +7 位作者 TerranovaM.L. OrlanducciS. SessaV. AbbasM. IbrahimK. ZhongJ. BottiS. DavoliI. 《Science Foundation in China》 CAS 2004年第1期38-41,共4页
The single-wall carbon nanotubes (SWCNs) were discovered in '93 and are made of pure carbon atoms just like a single sheet of graphite wrapped around acylindrical axis. The same material with slight varia-tions in... The single-wall carbon nanotubes (SWCNs) were discovered in '93 and are made of pure carbon atoms just like a single sheet of graphite wrapped around acylindrical axis. The same material with slight varia-tions in the geometrical arrangement yields different electronic properties, which could range from metallic to semiconducting behavior. They have fascinatingchemical, 展开更多
关键词 电子表征 单壁碳纳米棒 石墨 x射线吸收光谱法 结构分析
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