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BACKGROUND RECTIFICATION AND FEATURE EXTRACTION OF IMAGE IN A SPOT WELD OF AL ALLOY X-RAY DETECTION
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作者 T.Gang J.Zhang M.B.Zhang and F.X.Liu (1)AWPT National Key.,HIT,Harbin 15001,China 2)State 159 Factory,China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2000年第1期75-79,共5页
A primary study on Processing in X - ray inspection of spot weld for aluminum alloy spot welding,in- cluding for background simulation,acquisition of ideal binary image, and extraction and identifi- cation of defec... A primary study on Processing in X - ray inspection of spot weld for aluminum alloy spot welding,in- cluding for background simulation,acquisition of ideal binary image, and extraction and identifi- cation of defect features was presented. 展开更多
关键词 x - ray detection image processing spot weld aluminium alloy
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1,4-二苯基-6-苯基氨基-1,3,5-三嗪-2(1H)-硫酮的合成与晶体结构
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作者 朱晓彤 张荣丽 +2 位作者 刘永民 徐洲 姜波 《徐州医学院学报》 CAS 2013年第3期151-154,共4页
目的研究1,4-二苯基-6-苯基氨基-1,3,5-三嗪-2(1H)-硫酮(分子式C2,H16N4S,相对分子质量356.44)的合成方法和其单晶结构。方法先将一定量的苄脒、氢氧化钠和N,N-二甲基甲酰胺(DMF)混合放入10ml反应器中搅拌10min,然后将一... 目的研究1,4-二苯基-6-苯基氨基-1,3,5-三嗪-2(1H)-硫酮(分子式C2,H16N4S,相对分子质量356.44)的合成方法和其单晶结构。方法先将一定量的苄脒、氢氧化钠和N,N-二甲基甲酰胺(DMF)混合放入10ml反应器中搅拌10min,然后将一定量的苯基异硫氰酸酯加入反应器中,预搅拌20S后,在110℃温度下微波辐射(MWI)15min,高产率得到目标化合物。化合物的结构通过核磁共振氢谱(^1HNMR)、红外光谱(IR)和高分辨率气相色谱质谱(HRMS)验证,并通过X—ray单晶衍射进一步确定了产物的结构。结果合成的标题化合物C21H16N4S结构通过单晶X射线衍射分析确定,单斜晶系,空间群C2/c,a=22.94(2),b=9.5092(15),c=22.027(2)A,d=90°,D=110.473(2)°,^γ=90°,R=0.0465andwR:0.0758。分子中新形成的1,3,5-三嗪-2(1H)-硫酮环是个平面结构;它与相邻的苯环接近于共平面,二者的二面角为7.36(0.17);而它与相邻的N一取代苯环近似于垂直,二者的二面角为85.31(0.13)。结论提供了一种1,3,5-三嗪衍生物的绿色合成方法,并经过单晶衍生确定了其分子结构及分子结构中各个六员环之间的关系。 展开更多
关键词 1 3 5-三嗪衍生物 合成 微波辐射 xray单晶衍射
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One-pot synthesis and optical properties of In- and Sn-doped ZnO nanoparticles 被引量:1
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作者 Li-ping Wang Fu Zhang +1 位作者 Shuai Chen Zi-heng Bai 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2017年第4期455-461,共7页
Colloidal indium-doped zinc oxide (IZO) and tin-doped zinc oxide (ZTO) nanoparticles were successfully prepared in organic solution, with metal acetylacetonate as the precursor and oleylamine as the solvent. The cryst... Colloidal indium-doped zinc oxide (IZO) and tin-doped zinc oxide (ZTO) nanoparticles were successfully prepared in organic solution, with metal acetylacetonate as the precursor and oleylamine as the solvent. The crystal and optical properties were characterized by X-ray diffraction, UV−visible spectrophotometry, and fluorescence spectroscopy, respectively; the surface and structure morphologies were observed by scanning electron microscopy and transmission electron microscopy. The XRD patterns of the IZO and ZTO nanoparticles all exhibited similar diffraction peaks consistent with the standard XRD pattern of ZnO, although the diffraction peaks of the IZO and ZTO nanoparticles were slightly shifted with increasing dopant concentration. With increasing dopant concentration, the fluorescent emission peaks of the IZO nanoparticles exhibited an obvious red shift because of the difference in atomic radii of indium and zinc, whereas those of the ZTO nanoparticles exhibited almost no shift because of the similarity in atomic radii of tin and zinc. Furthermore, the sizes of the IZO and ZTO nanoparticles distributed in the ranges 20–40 and 20–25 nm, respectively, which is attributed to the difference in ionic radii of indium and tin. © 2017, University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg. 展开更多
关键词 Crystal structure Doping (additives) Electron microscopy fluorescence fluorescence spectroscopy High resolution transmission electron microscopy INDIUM Metal nanoparticles Nanoparticles Optical properties Scanning electron microscopy Semiconductor doping Tin Tin oxides Transmission electron microscopy x ray diffraction Zinc Zinc oxide
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Separation and Determination of Sulfur with Different Valance in Polysulfide Mixture
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作者 ZHOU Ji-hong CHEN Qi-yuan +1 位作者 ZHANG Ping-min YIN Zhou-lan 《Journal of Central South University》 SCIE EI CAS 2000年第3期149-151,共3页
A new process of separating sulfur with different valance from polysulfide mixtures was developed. Sulfide, sulfite and sulfur were separated by adding acetic acid in one step. The polysulfide mixture, sulfite solutio... A new process of separating sulfur with different valance from polysulfide mixtures was developed. Sulfide, sulfite and sulfur were separated by adding acetic acid in one step. The polysulfide mixture, sulfite solution and sulfur were oxidized to sulfate by hydrogen peroxide. The products were measured by X ray Fluorescence Spectrometer(XRF) using filter method preparative specimen. The measurement needs only one set of standard sample.The effects of temperature and pH values on the separation were discussed. The results show that the recoveries range from 98.0% to 101.3% of sulfidic sulfur S( II), 97.0% to 103.0% for sulfite S(IV) and 98.4% to 100.4% for polysulfidic sulfur S(0). 展开更多
关键词 POLYSULFIDE SEPARATION DETERMINATION x ray fluorescence spectrum valance
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MICROSTRUCTURAL CHANGE OF YSZ-SUPPORTED YBaCuO SUPPERCONDUCTING FILM BY PROTON BEAM BOMBARDMENTS
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作者 王广厚 罗成林 +7 位作者 潘国强 颜石乾 韩民 杨森祖 李元 吉争鸣 孙志坚 吴培亨 《Nuclear Science and Techniques》 SCIE CAS CSCD 1990年第3期129-136,共8页
Microstructural change of YBaCuO film/YSZ substrate with and without proton irradiation has been studied by scanning electron microscope and X- ray diffraction techniques. Structural analysis has shown that conversion... Microstructural change of YBaCuO film/YSZ substrate with and without proton irradiation has been studied by scanning electron microscope and X- ray diffraction techniques. Structural analysis has shown that conversion from tetragonal to orthorhombic phases, reduction of nonsuperconducting phase and preferential rearrangement of crystal grains are all favorable to the improvement of superconductivity in the YBaCuO film supported by YSZ substrate by proton beam bombardment. 展开更多
关键词 YBACUO superconducting FILM PROTON irradiation Scanning electron MICROSCOPE x - ray diffraction Conversion of PHASES
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New Advances in Structural Studies of Barium Rare-Earth Fluor-Carbonate Minerals
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作者 Shen Jinchuan Mi JinxiaoChina University of Geosciences , Wuhan 430074 《Journal of Earth Science》 SCIE CAS CSCD 1992年第1期21-28,共8页
This paper summarizes the new developments in the study of barium rare-earth fluor-carbonate mineral structures .The second order superstructure of cebaite -(Ce ) was solved by using high power X-ray single crystal di... This paper summarizes the new developments in the study of barium rare-earth fluor-carbonate mineral structures .The second order superstructure of cebaite -(Ce ) was solved by using high power X-ray single crystal diffractometer . Five kinds of coordination forms were found . All atoms in the cell , including C and F , were properly located . In the process of study in a cordylite-(Ce ), a new mineral was discovered , whose chemical formula is (Ca0.5□0.5) BaCe2 (CO3)4F . It is isostructural with baiyuneboite - (Ce ), but different in composition (Na in baiyuneboite- (Ce ) is substituted by Ca disorderly ) . On the basis of the studies a proposal to re-define cordylite-(Ce )as a mineral group name is put forth by the authors . Finally a new type of twinning of huanghoite-(Ce ) was found on the systematical absence of diffraction data by means of a single crystal diffractometer . 展开更多
关键词 rare - earth mineral crystal structure cordylite -(Ce) cebaite - (Ce) baiyuneboite - (Ce) huanghoite - (Ce) x - ray analysis .
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Study on the fluorescence quenching of ZnO by graphene oxide
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作者 理记涛 杨静 +3 位作者 周思华 王少辉 刘奎立 徐春祥 《Optoelectronics Letters》 EI 2016年第1期35-38,共4页
Zinc oxide(ZnO) microrod arrays were synthesized on Si substrate by a vapor phase transport(VPT) method in a tube furnace.The obtained ZnO microrods are characterized by scanning electron microscopy(SEM) and X-r... Zinc oxide(ZnO) microrod arrays were synthesized on Si substrate by a vapor phase transport(VPT) method in a tube furnace.The obtained ZnO microrods are characterized by scanning electron microscopy(SEM) and X-ray diffraction(XRD).The photoluminescence(PL) measurement indicates that the ZnO microrods have a strong ultraviolet(UV) emission centered at ~391 nm and a defect-related emission centered at ~530 nm.After the microrods were coated with graphene oxide(GO),the PL intensity of the hybrid microstructure is quenched compared with that of the bare one at the same excitation condition,and the PL intensity changes with the concentration of the GO.The fluorescence quenching mechanism is also discussed in this work. 展开更多
关键词 fluorescENCE QUENCHING Scanning electron microscopy x ray diffraction Zinc oxide
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Wool Surface Modification and Its Adhesion with Nano Finishing Agent
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作者 李龙 王卫 《Journal of Donghua University(English Edition)》 EI CAS 2009年第6期629-633,共5页
The launderability of wool fabrics treated by nano finoshing agent influences directly the functional endurance of he treated wool fabric. In order to investigate the effect of wool fibers surface modification on the ... The launderability of wool fabrics treated by nano finoshing agent influences directly the functional endurance of he treated wool fabric. In order to investigate the effect of wool fibers surface modification on the functional erdurance of nano finishinp wool fibers, in this paper, for the first time wool fibers were chemically modified by using NaClO aqueous and KMnO4 aqueous, and then chemically modified wool fibers and native wool fibers were treated using nano ZnO finishing agent, respectively. The launderability of wool fibers treated by nano finishing agent was investigated. The experimental results show that the chemically modified wool fibers have a good launderaility after being treated by nano ZnO finishing agent treating. The surface morphologies of wool fibers were observed by using SEM. It is got that there is a strong adbesion between nano ZnO and wool surface through XPS analysis. 展开更多
关键词 wool modification nano finishing agent x - ray photoelectron spectroscopy launderability
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The Different Patterns of Coronary Artery Calcification in Acute and Chronic Coronary Syndromes Determined by Electron Beam Computed Tomography
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作者 杜志民 罗初凡 +5 位作者 胡承恒 李怡 伍贵富 李向民 冯君 马虹 《South China Journal of Cardiology》 CAS 2002年第2期63-71,76,共10页
Objectives To compare the different patterns of coronary artery calcification (CAC) in acute and chronic coronary syndromes utilizing electron beam computed tomography. Background Pathologic, angiographic, and intraco... Objectives To compare the different patterns of coronary artery calcification (CAC) in acute and chronic coronary syndromes utilizing electron beam computed tomography. Background Pathologic, angiographic, and intracoronary ultrasound studies revealed sharp differences in the plaque morphology between patients with acute versus chronic coronary syndromes. Whether there are different patterns of coronary artery calcification in patients with stable angina pectoris (SAP) and in those with unstable angina pectoris (UAP) or acute myocardial infarction (AMI), however, remains unclear. Methods Two hundred and sixty - four patients, including 67 with SAP, 94 with UAP and 103 with AMI were studied with electron beam computed tomography for analysis of coronary artery calcification and with selective coronary angiography for determination of atherosclerotic lesions. CAC prevalence and calcium score were compared among three groups, and relation of CAC to the severity of atherosclerotic disease in the SAP and UAP patients was separately analyzed. Results Prevalence of CAC was 100 % in the SAP patients, significantly higher than the 87. 23 % in UAP patients and 86. 41 % among the patients with AMI ( P < 0. 05) . More patients and arteries in the SAP group had severe forms of calcium than those in the UAP and AMI group ( P < 0. 01), and the mean LN [CS + 1] (natural logarithm transformation of calcium score) of the SAP patients was much greater than that of the UAP and AMI patients (P < 0.001). The distribution of vessels with various CAC by luminal stenosis was different between SAP and UAP patients. The average CAC extent of the infarct - related arteries was less severe than that of the noninfarct - related arteries. Conclusions U-tilizing electron beam computed tomography, we demonstrated that there exist different patterns of coronary artery calcification in patients with acute versus chronic coronary syndromes, which may provide insight into the differences observed in the clinical and pathologic development between these two types of coronary artery disease. 展开更多
关键词 Coronary artery disease Calci-fication Tomography/x - ray computed
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线团-刚棒-线团三嵌段分子有序纳米结构的自组装 被引量:2
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作者 田立荣 钟克利 +1 位作者 陈铁 金龙一 《高分子通报》 CAS CSCD 北大核心 2011年第11期7-14,共8页
目前,在纳米科学和仿生化学等方面的一个非常吸引人的课题是构建一种新颖的、复杂的大分子或超分子体系,并通过设计连接有机嵌段单元使其具有很好的形状和功能。在线团-刚棒-线团三嵌段分子体系中,刚棒嵌段的各向异性和连接嵌段的微相... 目前,在纳米科学和仿生化学等方面的一个非常吸引人的课题是构建一种新颖的、复杂的大分子或超分子体系,并通过设计连接有机嵌段单元使其具有很好的形状和功能。在线团-刚棒-线团三嵌段分子体系中,刚棒嵌段的各向异性和连接嵌段的微相分离作用导致分子自组装形成各种有序聚集体,并且通过改变柔性链体积分数、分子长度、柔性链横截面积、刚棒中心侧链、刚棒形状等参数可以调控其自组装的聚集形态。本文详细总结了各种参数对线团-刚棒-线团三嵌段分子自组装结构所产生的影响,探讨了这些参数与构建超分子结构之间的关系,对今后设计合成具有自组装功能的分子具有指导性意义。 展开更多
关键词 线团-刚棒-线团三嵌段分子 自组装 超分子 纳米结构 xray衍射
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Enhanced near infrared emission in water-soluble NdF_3 nanocrystals by Ba^(2+) doping
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作者 樊婷 张勤远 姜中宏 《Chinese Optics Letters》 SCIE EI CAS CSCD 2012年第2期68-70,共3页
A simple and efficient method for the synthesis of water-soluble NdF3 and NdF3:Ba^2+ nanocrystals under hydrothermal conditions is established. The method involves the coating of the nanocrystals with a layer of hyd... A simple and efficient method for the synthesis of water-soluble NdF3 and NdF3:Ba^2+ nanocrystals under hydrothermal conditions is established. The method involves the coating of the nanocrystals with a layer of hydrophilic polymer polyvinylpyrrolidone (PVP). The as-prepared products are characterized by powder X-ray diffraction, field emission scanning electronic microscopy, Fourier transform infrared spectroscopy, and photoluminescence spectroscopy. The PVP coating transforms the nanocrystals into a biocompatible material and improves the fluorescence intensity of NdF3 in the near infrared (NIR) region. The morphology of the nanoparticles changes, whereas the fluorescence intensity of NdF3 in the NIR region increases when a small amount of Ba^2+ is doped into the NdF3/PVP nanoparticles. 展开更多
关键词 Biological materials Coatings fluorescENCE Fourier transform infrared spectroscopy NANOCRYSTALS Nanoparticles Photoluminescence spectroscopy x ray diffraction
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Enhanced ultraviolet emission from ZnO thin film covered by TiO_2 nanoparticles
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作者 徐林华 沈华 +1 位作者 李相银 朱日宏 《Chinese Optics Letters》 SCIE EI CAS CSCD 2009年第10期953-955,共3页
A ZnO thin film covered by TiO2 nanoparticles is prepared by electron beam evaporation. The structure and surface morphology of the sample are analyzed by X-ray diffraction (XRD) and atomic force microscopy (AFM),... A ZnO thin film covered by TiO2 nanoparticles is prepared by electron beam evaporation. The structure and surface morphology of the sample are analyzed by X-ray diffraction (XRD) and atomic force microscopy (AFM), respectively. Photoluminescence is used to investigate the fluorescent property of the ample. The results show that the ultraviolet (UV) emission of the ZnO thin film is greatly enhanced after it is covered by TiO2 nanoparticles while the green emission is suppressed. The enhanced UV emission mainly results from the fluorescence resonance energy transfer (FRET) between ZnO thin film and TiO: nanoparticles. This TiO2-ZnO composite thin film can be used to fabricate high-efficiency UV emitters. 展开更多
关键词 Atomic force microscopy Electron beams Energy transfer fluorescENCE Metallic films NANOPARTICLES Optical films Surface structure Thin film devices Thin films x ray diffraction Zinc oxide
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