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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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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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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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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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