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
The real-time monitoring of environmental radiation dose for nuclear fa-cilities is an important part of safety, in order to guarantee the accuracy of the monitoring results regular calibration is necessary. Around nu...The real-time monitoring of environmental radiation dose for nuclear fa-cilities is an important part of safety, in order to guarantee the accuracy of the monitoring results regular calibration is necessary. Around nuclear facilities there are so many environmental dosimeters installed dispers-edly, because of its huge quantity, widely distributed, and in real-time monitoring state;it will cost lots of manpower and finance if it were tak-en to calibrate on standard laboratory;what’s more it will make the en-vironment out of control. To solve the problem of the measurement ac-curacy of the stationary gamma radiation dosimeter, an on-site calibra-tion method is proposed. The radioactive source is X-ray spectrum, and the dose reference instrument which has been calibrated by the national standard laboratory is a high pressure ionization. On-site calibration is divided into two parts;firstly the energy response experiment of dosim-eter for high and low energy is done in the laboratory, and the energy response curve is obtained combining with Monte Carlo simulation;sec-ondly experiment is carried out in the field of the measuring dosimeter, and the substitution method to calibrate the dosimeter is used;finally the calibration coefficient is gotten through energy curve correction. In order to verify the accuracy of on-site calibration method, the calibrated dosimeter is test in the standard laboratory and the error is 3.4%. The re-sult shows that the on-site calibration method using X-ray is feasible, and it can improves the accuracy of the measurement results of the stationary γ-ray instrument;what’s more important is that it has great reference value for the radiation safety management and radiation environment evaluation.展开更多
Background: In 2010, the International Atomic Energy Agency launched the “3A’s campaign” as an effective tool for primary cancer prevention. In 2011, the American Association of Physicists in Medicine recommended t...Background: In 2010, the International Atomic Energy Agency launched the “3A’s campaign” as an effective tool for primary cancer prevention. In 2011, the American Association of Physicists in Medicine recommended the size specific dose estimate (SSDE). Objectives: To audit doses of Coronary CT Angiography (Coronary CTA) in tertiary care referral center. Methods: We reviewed 998 consecutive Coronary CTA (from 2007 to 2012). Doses (CTDIvol mGy), DLP (mGy*cm), effective dose (DLP*0.014, mSv) were on-line archived. SSDE was estimated retrospectively. Appropriateness score was evaluated for exams performed from the 2010. Results: Overall median dose per Coronary CTA was 49.7 mGy for CTDIvol, 55.5 mGy for SSDE, 994.96 mGy*cm for DLP, 13.9 mSv for effective dose. Median DLP decreased over time (1452.94 in 2007, 1605.56 in 2008, 1113.49 in 2009, 759.99 in 2010, 448.61 in 2011 and 497.88 mGy*cm in 2012, p < 0.0001). SSDE was proportional to the size dependent factor (SDF);in patients with SDF > 1 (88%) CTDIvol underestimated SSDE (48.49 vs 57.19 mGy), whilst in patients with SDF < 1 (12%) CTDIvol overestimated SSDE (56.46 vs 50.3 mGy). Scans were appropriate in 58%, uncertain in 24%, and inappropriate in 18% of cases. Doses were similar in appropriate, uncertain or inappropriate examinations and in excellent-to-good (81%) vs. sufficient-to-poor (19%) image quality exams. Conclusions: Coronary CTA reference doses can be very misleading. SSDE can allow individual technique optimization. The dose is similar in appropriate and inappropriate examinations, and unrelated to image quality. The rate of inappropriate examinations is still too high even after dissemination of guidelines.展开更多
Fourier transform infrared spectroscopy （FTIR） was employed to study the human epidermis larynx carcinoma cell lines （Hep-2） which were irradiated by different doses of X-ray. The results show that （1） the irrad...Fourier transform infrared spectroscopy （FTIR） was employed to study the human epidermis larynx carcinoma cell lines （Hep-2） which were irradiated by different doses of X-ray. The results show that （1） the irradiation of X-ray damages the structure of the CH3 groups of the thymine in DNA, which restrains the reproduction of Hep-2 cells effectively, （2） the 8 Gy dose of X-ray irradiation changes the framework and the relative contents of some proteins, lipids and the nucleic acid molecules intercellular in the greatest degree, and （3） the 8 Gy dose of X-ray irradiation is the best irradiation dose for lowering the degree of the cancerization of Hep-2 cells according to the criteria for the degree of the cancerization reported recently. Meanwhile, the apoptosis of these cells were detected by using flow cytometry （FCM） primarily. It shows that the apoptotic ratio of the Hep-2 cells depends on the irradiation dose to some extent, but is not linearly. And the apoptotic ratio of the 12 Gy dose group is the maximum （20.36%）, but the apoptotic ratios of the 2 to 8 Gy dose groups change little.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
A series of Mo/Si multilayers with the same periodic length and different periodic number were prepared by magnetron sputtering, whose top layers were respectively Mo layer and Si layer. Periodic length and interface ...A series of Mo/Si multilayers with the same periodic length and different periodic number were prepared by magnetron sputtering, whose top layers were respectively Mo layer and Si layer. Periodic length and interface roughness of Mo/Si multilayers were determined by small angle X-ray diffraction （SAXRD）. Surface roughness change curve of Mo/Si multilayer with increasing layer number was studied by atomic force microscope （AFM）. Soft X-ray reflectivity of Mo/Si multilayers was measured in National Synchrotron Radiation Laboratory （NSRL）. Theoretical and experimental results show that the soft X-ray reflectivity of Mo/Si multilayer is mainly determined by periodic number and interface roughness, surface roughness has little effect on reflectivity.展开更多
OBJECTIVE: To investigate the role of apoptosis in radiation-induced mouse thymus lymphocyte damage and repair and provide the basis for understanding the molecular mechanism of radiation-induced lymphocyte damage and...OBJECTIVE: To investigate the role of apoptosis in radiation-induced mouse thymus lymphocyte damage and repair and provide the basis for understanding the molecular mechanism of radiation-induced lymphocyte damage and repair as well as the prevention and treatment of acute radiation sickness. METHODS: We studied the dynamic changes of apoptosis of mouse thymus lymphocytes and the expression of bax and bcl-2 gene products after 2, 4, 6 and 8 Gy of whole body gamma-irradiation using in situ terminal labeling, DNA electrophoresis and immunohistochemical techniques. RESULTS: At the early stage after irradiation, the percentage of apoptotic lymphocytes increased rapidly in accordance with the increasing of radiation doses, while the counts of the thymus and peripheral lymphocytes decreased sharply, showing an opposite change to lymphocyte apoptosis. After 6 Gy gamma-irradiation, typical morphological characteristics of thymus apoptotic lymphocytes in early, middle and late stages were found by transmission electron microscopy. The thymus lymphocytes displayed characteristic DNA ladders 4 hr and 8 hr after 2-6 Gy gamma-irradiation,using DNA gel electrophoresis techniques. Abnormal expression of bcl-2 and bax gene products were shown in irradiated lymphocytes. CONCLUSIONS: Apoptosis plays an important role in the process of radiation-induced mouse thymus lymphocyte damage and repair. Bcl-2 and Bax proteins may regulate the process of lymphocyte apoptosis.展开更多
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
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
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The real-time monitoring of environmental radiation dose for nuclear fa-cilities is an important part of safety, in order to guarantee the accuracy of the monitoring results regular calibration is necessary. Around nuclear facilities there are so many environmental dosimeters installed dispers-edly, because of its huge quantity, widely distributed, and in real-time monitoring state;it will cost lots of manpower and finance if it were tak-en to calibrate on standard laboratory;what’s more it will make the en-vironment out of control. To solve the problem of the measurement ac-curacy of the stationary gamma radiation dosimeter, an on-site calibra-tion method is proposed. The radioactive source is X-ray spectrum, and the dose reference instrument which has been calibrated by the national standard laboratory is a high pressure ionization. On-site calibration is divided into two parts;firstly the energy response experiment of dosim-eter for high and low energy is done in the laboratory, and the energy response curve is obtained combining with Monte Carlo simulation;sec-ondly experiment is carried out in the field of the measuring dosimeter, and the substitution method to calibrate the dosimeter is used;finally the calibration coefficient is gotten through energy curve correction. In order to verify the accuracy of on-site calibration method, the calibrated dosimeter is test in the standard laboratory and the error is 3.4%. The re-sult shows that the on-site calibration method using X-ray is feasible, and it can improves the accuracy of the measurement results of the stationary γ-ray instrument;what’s more important is that it has great reference value for the radiation safety management and radiation environment evaluation.
文摘Background: In 2010, the International Atomic Energy Agency launched the “3A’s campaign” as an effective tool for primary cancer prevention. In 2011, the American Association of Physicists in Medicine recommended the size specific dose estimate (SSDE). Objectives: To audit doses of Coronary CT Angiography (Coronary CTA) in tertiary care referral center. Methods: We reviewed 998 consecutive Coronary CTA (from 2007 to 2012). Doses (CTDIvol mGy), DLP (mGy*cm), effective dose (DLP*0.014, mSv) were on-line archived. SSDE was estimated retrospectively. Appropriateness score was evaluated for exams performed from the 2010. Results: Overall median dose per Coronary CTA was 49.7 mGy for CTDIvol, 55.5 mGy for SSDE, 994.96 mGy*cm for DLP, 13.9 mSv for effective dose. Median DLP decreased over time (1452.94 in 2007, 1605.56 in 2008, 1113.49 in 2009, 759.99 in 2010, 448.61 in 2011 and 497.88 mGy*cm in 2012, p < 0.0001). SSDE was proportional to the size dependent factor (SDF);in patients with SDF > 1 (88%) CTDIvol underestimated SSDE (48.49 vs 57.19 mGy), whilst in patients with SDF < 1 (12%) CTDIvol overestimated SSDE (56.46 vs 50.3 mGy). Scans were appropriate in 58%, uncertain in 24%, and inappropriate in 18% of cases. Doses were similar in appropriate, uncertain or inappropriate examinations and in excellent-to-good (81%) vs. sufficient-to-poor (19%) image quality exams. Conclusions: Coronary CTA reference doses can be very misleading. SSDE can allow individual technique optimization. The dose is similar in appropriate and inappropriate examinations, and unrelated to image quality. The rate of inappropriate examinations is still too high even after dissemination of guidelines.
基金the Science and Technol-ogy Department of Henan province (No.0624410052)the key Ion Beam Bioengineering Laboratory of Henan Province+1 种基金the Pathology Laboratory of Zhengzhou Uni-versitythe People's Hospital of Henan Province.
文摘Fourier transform infrared spectroscopy （FTIR） was employed to study the human epidermis larynx carcinoma cell lines （Hep-2） which were irradiated by different doses of X-ray. The results show that （1） the irradiation of X-ray damages the structure of the CH3 groups of the thymine in DNA, which restrains the reproduction of Hep-2 cells effectively, （2） the 8 Gy dose of X-ray irradiation changes the framework and the relative contents of some proteins, lipids and the nucleic acid molecules intercellular in the greatest degree, and （3） the 8 Gy dose of X-ray irradiation is the best irradiation dose for lowering the degree of the cancerization of Hep-2 cells according to the criteria for the degree of the cancerization reported recently. Meanwhile, the apoptosis of these cells were detected by using flow cytometry （FCM） primarily. It shows that the apoptotic ratio of the Hep-2 cells depends on the irradiation dose to some extent, but is not linearly. And the apoptotic ratio of the 12 Gy dose group is the maximum （20.36%）, but the apoptotic ratios of the 2 to 8 Gy dose groups change little.
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A series of Mo/Si multilayers with the same periodic length and different periodic number were prepared by magnetron sputtering, whose top layers were respectively Mo layer and Si layer. Periodic length and interface roughness of Mo/Si multilayers were determined by small angle X-ray diffraction （SAXRD）. Surface roughness change curve of Mo/Si multilayer with increasing layer number was studied by atomic force microscope （AFM）. Soft X-ray reflectivity of Mo/Si multilayers was measured in National Synchrotron Radiation Laboratory （NSRL）. Theoretical and experimental results show that the soft X-ray reflectivity of Mo/Si multilayer is mainly determined by periodic number and interface roughness, surface roughness has little effect on reflectivity.
文摘OBJECTIVE: To investigate the role of apoptosis in radiation-induced mouse thymus lymphocyte damage and repair and provide the basis for understanding the molecular mechanism of radiation-induced lymphocyte damage and repair as well as the prevention and treatment of acute radiation sickness. METHODS: We studied the dynamic changes of apoptosis of mouse thymus lymphocytes and the expression of bax and bcl-2 gene products after 2, 4, 6 and 8 Gy of whole body gamma-irradiation using in situ terminal labeling, DNA electrophoresis and immunohistochemical techniques. RESULTS: At the early stage after irradiation, the percentage of apoptotic lymphocytes increased rapidly in accordance with the increasing of radiation doses, while the counts of the thymus and peripheral lymphocytes decreased sharply, showing an opposite change to lymphocyte apoptosis. After 6 Gy gamma-irradiation, typical morphological characteristics of thymus apoptotic lymphocytes in early, middle and late stages were found by transmission electron microscopy. The thymus lymphocytes displayed characteristic DNA ladders 4 hr and 8 hr after 2-6 Gy gamma-irradiation,using DNA gel electrophoresis techniques. Abnormal expression of bcl-2 and bax gene products were shown in irradiated lymphocytes. CONCLUSIONS: Apoptosis plays an important role in the process of radiation-induced mouse thymus lymphocyte damage and repair. Bcl-2 and Bax proteins may regulate the process of lymphocyte apoptosis.
文摘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.
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.
