Temporal and spectral characteristics of X-ray emission from 60 flares of intensity ≥C class observed by the Solar X-ray Spectrometer (SOXS) during 2003-2011 are presented. We analyze the X-ray emission observed in...Temporal and spectral characteristics of X-ray emission from 60 flares of intensity ≥C class observed by the Solar X-ray Spectrometer (SOXS) during 2003-2011 are presented. We analyze the X-ray emission observed in four and three energy bands by the Si and Cadmium-Zinc-Telluride (CZT) detectors, respectively. The number of peaks in the intensity profile of the flares varies between 1 and 3. We find moderate correlation (R ~=0.2) between the rise time and the peak flux of the first peak of the flare irrespective of energy band, which is indicative of its energy-independent nature. Moreover, the magnetic field complexity of the flaring region is found to be highly anti-correlated (R = 0.61) with the rise time of the flares while positively correlated (R = 0.28) with the peak flux of the flare. The time delay between the peak of the X-ray emission in a given energy band and that in 25-30keV decreases with increasing energy, suggesting conduction cooling is dominant in the lower energies. Analysis of 340 spectra from 14 flares reveals that the peak of differential emission measure (DEM) evolution is delayed by 60-360 s relative to that of the temperature, and this time delay is inversely proportional to the peak flux of the flare. We conclude that temporal and intensity characteristics of flares are dependent on energy as well as the magnetic field configuration of the active region.展开更多
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
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
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
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
基金the Gujarat Council on Science and Technology(GUJCOST),Dept.of Science&Technology,Govt.of Gujarat under the minor research project grants schemeGUJCOST for the financial assistance+1 种基金supported by NSFC(Grant Nos.41474151,41774150 and 4171101125)the International Postdoctoral Program of USTC
文摘Temporal and spectral characteristics of X-ray emission from 60 flares of intensity ≥C class observed by the Solar X-ray Spectrometer (SOXS) during 2003-2011 are presented. We analyze the X-ray emission observed in four and three energy bands by the Si and Cadmium-Zinc-Telluride (CZT) detectors, respectively. The number of peaks in the intensity profile of the flares varies between 1 and 3. We find moderate correlation (R ~=0.2) between the rise time and the peak flux of the first peak of the flare irrespective of energy band, which is indicative of its energy-independent nature. Moreover, the magnetic field complexity of the flaring region is found to be highly anti-correlated (R = 0.61) with the rise time of the flares while positively correlated (R = 0.28) with the peak flux of the flare. The time delay between the peak of the X-ray emission in a given energy band and that in 25-30keV decreases with increasing energy, suggesting conduction cooling is dominant in the lower energies. Analysis of 340 spectra from 14 flares reveals that the peak of differential emission measure (DEM) evolution is delayed by 60-360 s relative to that of the temperature, and this time delay is inversely proportional to the peak flux of the flare. We conclude that temporal and intensity characteristics of flares are dependent on energy as well as the magnetic field configuration of the active region.
文摘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.
文摘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.
文摘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 .
文摘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.