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Comparison of efficacy of lung ultrasound and chest X-ray in diagnosing pulmonary edema and pleural effusion in ICU patients: A single centre, prospective, observational study
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作者 Kunal Tewari Sumanth Pelluru +5 位作者 Deepak Mishra Nitin Pahuja Akash Ray Mohapatra Jyotsna Sharma Om Bahadur Thapa Manjot Multani 《Open Journal of Anesthesiology》 2024年第3期41-50,共10页
Background and Aims While chest X-ray (CXR) has been a conventional tool in intensive care units (ICUs) to identify lung pathologies, computed tomography (CT) scan remains the gold standard. Use of lung ultrasound (LU... Background and Aims While chest X-ray (CXR) has been a conventional tool in intensive care units (ICUs) to identify lung pathologies, computed tomography (CT) scan remains the gold standard. Use of lung ultrasound (LUS) in resource-rich ICUs is still under investigation. The present study compares the utility of LUS to that of CXR in identifying pulmonary edema and pleural effusion in ICU patients. In addition, consolidation and pneumothorax were analyzed as secondary outcome measures. Material and Methods This is a prospective, single centric, observational study. Patients admitted in ICU were examined for lung pathologies, using LUS by a trained intensivist;and CXR done within 4 hours of each other. The final diagnosis was ascertained by an independent senior radiologist, based on the complete medical chart including clinical findings and the results of thoracic CT, if available. The results were compared and analyzed. Results Sensitivity, specificity and diagnostic accuracy of LUS was 95%, 94.4%, 94.67% for pleural effusion;and 98.33%, 97.78%, 98.00% for pulmonary edema respectively. Corresponding values with CXR were 48.33%, 76.67%, 65.33% for pleural effusion;and 36.67%, 82.22% and 64.00% for pulmonary edema respectively. Sensitivity, specificity and diagnostic accuracy of LUS was 91.30%, 96.85%, 96.00% for consolidation;and 100.00%, 79.02%, 80.00% for pneumothorax respectively. Corresponding values with CXR were 60.87%, 81.10%, 78.00% for consolidation;and 71.3%, 97.20%, 96.00% for pneumothorax respectively. Conclusion LUS has better diagnostic accuracy in diagnosis of pleural effusion and pulmonary edema when compared with CXR and is thus recommended as an effective alternative for diagnosis of these conditions in acute care settings. Our study recommends that a thoracic CT scan can be avoided in most of such cases. 展开更多
关键词 Chest x ray (CxR) CONSOLIDATION Pulmonary edema Pleural effusion Lung ultrasound (LUS) PNEUMOTHORAx
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Effects of Corticosterone, cAMP, cGMP, Ca^(2+), and Protein Kinase C on Apoptosis of Mouse Thymocytes Induced by X-ray Irradiation 被引量:4
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作者 SHOU-LIANG GONG LI-HUA DONG +5 位作者 GUANG-WEI LIU PING-SHENG GONG WEN-TIAN LU HONG-GUANG ZHAO XIAO-JING JIA YONG ZHAO 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2008年第2期167-172,共6页
Objective To observe the effects of signal factors of corticosterone (CS), cAMP, cGMP, Ca^2+ and protein kinase C (PKC) on lymphocyte apoptosis in mouse thymus induced by X-rays of 4 Gy in vitro. Methods The DNA ... Objective To observe the effects of signal factors of corticosterone (CS), cAMP, cGMP, Ca^2+ and protein kinase C (PKC) on lymphocyte apoptosis in mouse thymus induced by X-rays of 4 Gy in vitro. Methods The DNA lyric rate for thymocytes was measured by fluomspectrophotometry. Results The DNA lyric rate for thymocytes 4-8 hours after irradiation with 2-8 Gy was significantly higher than that in the control (P〈0.01). As compared with the control, the DNA lyric rate for thymocytes treated with 0.01 μnol/L CS (P〈0.01), 50 ng/mL cAMP (P〈0.01), 0.05-0.4 μg/mL ionomycin (Iono, P〈0.05 or P〈0.01) or 0.05-0.4 ng/mL phorbol myristate acetate (PMA, P〈0.05 or P〈0.01), respectively, was significantly increased, while the rate for thymocytes treated with 50 ng/mL cGMP was not significantly increased. The DNA lyric rate for thymocytes treated with 0.01 μmol/L CS (P〈0.01), 50 ng/mL cAMP (P〈0.01), 0.2 and 0.4 μg/mL Iono (P〈0.05), and 0.2 and 0.4 ng/mL PMA (P〈0.05) plus 4-Gy irradiation, respectively, was significantly higher than that treated with single 4-Gy irradiation, while the rate for thymocytes treated with 50 ng/mL cGMP plus 4-Gy irradiation was not increased. When both 0.4 I.tg/mL Iono and 0.4 ng/mL PMA acted on the thymocytes, the DNA lyric rate for thymocytes was significantly higher than that in the control (P〈0.01), the DNA lytic rate for thymocytes treated with both 0.4 μg/mL Iono and 0.4 ng/mL PMA plus 4-Gy irradiation was significantly higher than that treated with single 4-Gy irradiation (P〈0.05), but was Iono plus 4-Gy irradiation or 0.4 ng/mL PMA plus 4-Gy irradiation. can promote thymocyte apoptosis induced by larger dose X-rays. not significantly higher than that treated with 0.4 μg/mL Conclusion CS, cAMP, Ca^2+, and PKC signal factors can promote thymocyte apoptosis induced by larger dose X-rays. 展开更多
关键词 CORTICOSTERONE CAMP CGMP Ca^2+ PKC x-ray irradiation LYMPHOCYTE APOPTOSIS
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Investigation on the hydrodynamics of slab x-ray laser plasma by nonuiform line focused laser irradiation
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作者 程涛 李英骏 +1 位作者 孟立民 李希波 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第2期260-265,共6页
Based on the two-dimensional model, this paper compares the hydrodynamics of slab x-ray laser plasma produced by different nonuniform line focused irradiations. It finds that the average intensity and the duration of ... Based on the two-dimensional model, this paper compares the hydrodynamics of slab x-ray laser plasma produced by different nonuniform line focused irradiations. It finds that the average intensity and the duration of laser pulse and the overall shape of the intensity distribution in the focal line have different influences on the plasma. Calculations show that the evolution of temperature variation is more sensitive to the pulse duration and the electron density variation is more sensitive to the pulse intensity. Pulses with duration of 200 ps to 500 ps and with intensity of 0.2 TW/cm2 to 1.0 TW/cm2 are proved acceptable in slab x-ray lasers. 展开更多
关键词 PLASMA slab x-ray laser nonuniform line focused laser irradiation HYDRODYNAMICS
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烟草粉螟卵黄原蛋白基因鉴定及其对X射线胁迫的响应
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作者 赵钧 徐鹿 +3 位作者 苗圃 李成军 吴孔明 李淑君 《中国烟草学报》 CAS CSCD 北大核心 2024年第3期132-138,共7页
【背景和目的】卵黄原蛋白(vitellogenin,Vg)是昆虫卵黄发生的关键物质,为探索X射线辐照胁迫对烟草粉螟Vg基因转录表达和雌成虫繁殖力的影响。【方法】采用RT-PCR技术克隆烟草粉螟Vg基因的全长并进行生物信息学分析,利用qPCR技术检测在... 【背景和目的】卵黄原蛋白(vitellogenin,Vg)是昆虫卵黄发生的关键物质,为探索X射线辐照胁迫对烟草粉螟Vg基因转录表达和雌成虫繁殖力的影响。【方法】采用RT-PCR技术克隆烟草粉螟Vg基因的全长并进行生物信息学分析,利用qPCR技术检测在烟草粉螟雌成虫不同组织(足、头、中肠、脂肪体、卵巢和表皮)的表达量和雌成虫在不同X射线辐照剂量(50,100和150 Gy)胁迫下该基因的相对表达量以及对其蛹羽化率、成虫寿命、产卵量、卵孵化率的影响。【结果】(1)克隆获得烟草粉螟卵黄原蛋白基因,命名为EeVg(GenBank登录号:OM804251),开放阅读框(ORF)长度为5337bp,编码1778个氨基酸。(2)EeVg基因在雌成虫的脂肪体中相对表达量最高,为头部表达量的17.96倍。(3)100和150 Gy的X射线辐照雌蛹极显著地降低EeVg在烟草粉螟羽化后的表达量,分别为对照的0.34倍和0.09倍。(4)剂量为50、100和150 Gy的X射线辐照降低烟草粉螟雌蛹羽化率和成虫寿命(87.78%~75.56%和6.40~4.17d),显著降低雌蛾的产卵量和卵孵化率(55.27~20.37粒和76.67%~72.22%)。【结论】高剂量的X射线辐照胁迫可使EeVg基因表达量显著下调,显著降低烟草粉螟繁殖力,为深入研究X射线影响烟草粉螟繁殖力的分子机制奠定了基础。 展开更多
关键词 烟草粉螟 卵黄原蛋白基因 x射线辐照 表达量 繁殖力
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石墨烯场效应晶体管的X射线总剂量效应
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作者 李济芳 郭红霞 +6 位作者 马武英 宋宏甲 钟向丽 李洋帆 白如雪 卢小杰 张凤祁 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第5期344-350,共7页
本文针对不同结构、尺寸的石墨烯场效应晶体管(graphene field effect transistors,GFET)开展了基于10 keV-X射线的总剂量效应研究.结果表明,随累积剂量的增大,不同结构GFET的狄拉克电压V_(Dirac)和载流子迁移率μ不断退化;相比于背栅型... 本文针对不同结构、尺寸的石墨烯场效应晶体管(graphene field effect transistors,GFET)开展了基于10 keV-X射线的总剂量效应研究.结果表明,随累积剂量的增大,不同结构GFET的狄拉克电压V_(Dirac)和载流子迁移率μ不断退化;相比于背栅型GFET,顶栅型GFET的辐射损伤更加严重;尺寸对GFET器件的总剂量效应决定于器件结构;200μm×200μm尺寸的顶栅型GFET损伤最严重,而背栅型GFET是50μm×50μm尺寸的器件损伤最严重.研究表明:对于顶栅型GFET,辐照过程中在栅氧层中形成的氧化物陷阱电荷的积累是V_(Dirac)和μ降低的主要原因.背栅型GFET不仅受到辐射在栅氧化层中产生的陷阱电荷的影响,还受到石墨烯表面的氧吸附的影响.在此基础上,结合TCAD仿真工具实现了顶栅器件氧化层中辐射产生的氧化物陷阱电荷对器件辐射响应规律的仿真.相关研究结果对于石墨烯器件的抗辐照加固研究具有重大意义. 展开更多
关键词 石墨烯场效应晶体管 x射线辐照 总剂量效应
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X射线辐照对彩色马铃薯贮藏保鲜效果的影响
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作者 蔚江涛 白俊青 +8 位作者 李奎 牛伟 康璐瑶 寇莉萍 王瑞瑶 李世超 王冬冬 候德华 陈勤 《食品工业科技》 CAS 北大核心 2024年第15期322-331,共10页
为探究不同剂量X射线辐照对彩色马铃薯发芽和贮藏品质的影响,本研究以彩色马铃薯黄玫瑰3号、紫玫瑰3号、红玫瑰5号和普通马铃薯为试验原料,采用0、100、300、500 Gy不同剂量的5 MeV电子束转靶X射线处理,将处理后的马铃薯贮藏于常温(20&#... 为探究不同剂量X射线辐照对彩色马铃薯发芽和贮藏品质的影响,本研究以彩色马铃薯黄玫瑰3号、紫玫瑰3号、红玫瑰5号和普通马铃薯为试验原料,采用0、100、300、500 Gy不同剂量的5 MeV电子束转靶X射线处理,将处理后的马铃薯贮藏于常温(20±2)℃、相对湿度为80%~90%的条件下,分析贮藏期的发芽率、失重率、硬度、VC含量、干物质含量和呼吸强度的参数变化,研究X射线辐照处理对马铃薯外观品质、营养品质的影响及贮藏保鲜效果。结果表明:X射线辐照处理降低了马铃薯贮藏中后期的呼吸强度,延缓了贮藏过程中的失重、硬度下降及VC含量的损失,其中黄玫瑰3号、紫玫瑰3号、红玫瑰5号和普通马铃薯100 Gy辐照处理组与对照组相比,失重率分别降低12.76%、5.31%、6.05%和1.43%,贮藏末期相对贮藏初期硬度下降程度分别降低12.98%、6.40%、8.34%和7.13%,VC含量损失率分别降低17.71%、22.80%、13.52%和14.65%;4个品种马铃薯经过不同剂量X射线辐照处理后,贮藏至240 d以上均未出现发芽现象;100 Gy低剂量X射线辐照处理即可达到理想的抑芽效果,且延缓失重、硬度下降方面均优于300、500 Gy,可作为彩色马铃薯和普通马铃薯辐照保鲜工业应用的推荐工艺剂量。本研究工作为X射线辐照技术在彩色马铃薯贮藏保鲜中的应用提供了理论依据和技术指导。 展开更多
关键词 彩色马铃薯 x 射线辐照 抑芽 贮藏保鲜
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αB-crystallin malondialdehyde,superoxide dismutase, and lutathione peroxidase changes in X-ray irradiated rat lens 被引量:1
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作者 Guo-Xu Xu, Guo-Tong Xu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2011年第4期365-370,共6页
AIM: To evaluate αB-crystallin malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GPx) changes in X-ray irradiated rat lens. METHODS: Eight-week-old Sprague-Dawley male rats received X-ray ... AIM: To evaluate αB-crystallin malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GPx) changes in X-ray irradiated rat lens. METHODS: Eight-week-old Sprague-Dawley male rats received X-ray irradiation to the head with rest of the body protected. The exposure dose ranged from 2 to 25 Grays (Gy). The cataract status were examined by slit lamp and rated with 'four-grade systems' post-irradiation. The lens MDA level, and the activities of SOD and GPx were measured in a short-term experiment post-irradiation, and αB-crystallin protein levels were quantified. RESULTS: The lenses of normal control and the X-ray irradiated groups with the dose up to 10 Gy remained transparent throughout the experiment. The lens first appeared tiny scatters, and even lamellar opacities in the posterior capsule 45 days post-irradiation with the dose of 15 Gy, and progressed slowly to the advance stage of cataract; while, for the higher dose (25 Gy), the opacity of lens appeared much earlier, and progressed more rapidly to mature stage of cataract within 1 month. At the end of the observation (90 days post-irradiation), almost all lenses became complete opacity with the higher dose (25 Gy). The degree of lens opacity was rated accordingly. The lens MDA level was increased, and SOD and GPx activities were decreased with a dose-dependent manner post-irradiation. The αB-crystallin protein level was decreased dose-dependently at the end point of observation. CONCLUSION: Oxidative events and αB-crystallin may play important roles in the pathogenesis of cataract in X-ray irradiated rat lens. 展开更多
关键词 αB-crystallin malondialdehyde superoxide dismutase glutathione peroxidase x-ray irradiation CATARACT
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Effect of p53 on lung carcinoma cells irradiated by carbon ions or X-rays 被引量:1
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作者 XIE Yi ZHANG Hong +4 位作者 HAO Jifang ZHAO Weiping WU Zhenhua QIU Rong WANG Xiaohu 《Nuclear Science and Techniques》 SCIE CAS CSCD 2009年第3期146-151,共6页
The study is to investigate the feasibility and advantages of heavy ion beams on radiotherapy. The cellular cycle and apoptosis, cell reproductive death and p53 expression evaluated with flow cytometry, clonogenic sur... The study is to investigate the feasibility and advantages of heavy ion beams on radiotherapy. The cellular cycle and apoptosis, cell reproductive death and p53 expression evaluated with flow cytometry, clonogenic survival assays and Western blot analysis were examined in lung carcinoma cells after exposure to 89.63 MeV/u carbon ion and 6 MV X-ray irradiations, respectively. The results showed that the number colonyforming assay of A549 was higher than that of H1299 cells in two radiation groups; A549 cellular cycle was arrested in G2/M in 12 h and the percentage of apoptosis ascended at each time point of carbon ion radiation with doses, the expression of p53 upregulated with doses exposed to X-ray or carbon ion. The cell number in G2/M of H1299 and apoptosis were increasing at all time points with doses in 12C6+ ion irradiation group. The results suggested that the effects of carbon ions or X rays irradiation on lung carcinoma cells were different, 12C6+ ion irradiation could have more effect on upregulating the expression of p53 than X-ray, and the upregulated expression of p53 might produce the cellular cycle G2/M arrested, apoptosis increasing; and p53 gene might affect the lung cancer cells radiosensitivity. 展开更多
关键词 肺癌 诊断 治疗 癌细胞
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X-irradiation for inhibiting glial scar formation in injured spinal cord 被引量:1
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作者 Guangzhi Ning Renhui Chen +4 位作者 Yulin Li Qiang Wu Qiuli Wu Yan Li Shiqing Feng 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第17期1582-1589,共8页
X-irradiation has a beneficial effect in treating spinal cord injury. We supposed that X-irradiation could improve the microenvironment at the site of a spinal cord injury and inhibit glial scar formation. Thus, this ... X-irradiation has a beneficial effect in treating spinal cord injury. We supposed that X-irradiation could improve the microenvironment at the site of a spinal cord injury and inhibit glial scar formation. Thus, this study was designed to observe the effects of 8 Gy X-irradiation on the injury site at 6 hours and 2, 4, 7, and 14 days post injury, in terms of improvement in the microenvironment and hind limb motor function. Immunohistochemistry showed that the expression of macrophage marker ED-1 and the area with glial scar formation were reduced. In addition, the Basso, Beattie and Bresnahan score was higher at 7 days post injury relative to the other time points post injury. Results indicated that X-irradiation at a dose of 8 Gy can inhibit glial scar formation and alleviate the inflammatory reaction, thereby repairing spinal cord injury. X-irradiation at 7 days post spinal cord injury may be the best time window. 展开更多
关键词 neural regeneration spinal cord glial scar x-irradiation functional recovery ASTROCYTES grants-supported paper NEUROREGENERATION
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Layered Ag-graphene films synthesized by Gamma ray irradiation for stable lithium metal ano des in carb on ate-based electrolytes
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作者 Jiaxiang Liu Haoshen Ma +5 位作者 Zhipeng Wen Huiyang Li Jin Yang Nanbiao Pei Peng Zhang Jinbao Zhao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第1期354-363,I0010,共11页
Lithium metal batteries are considered as high energy density battery systems with very promising prospects and have bee n widely studied.However,The uncon trollable plating/strippi ng behavior,infinite volume change ... Lithium metal batteries are considered as high energy density battery systems with very promising prospects and have bee n widely studied.However,The uncon trollable plating/strippi ng behavior,infinite volume change and den drites formation of lithium metal anode restrict the applicati on.The unc on trolled n ucleati on of lithium caused by the non uniform multi-physical field distributions,can lead to the undesirable lithium deposition.Herein,a graphene composite uniformly loaded with Ag nano-particles(Ag NPs)is prepared through a facile Gamma ray irradiation method and assembled into self-supported film with layered structure(Ag-rGO film).Whe n such film is used as a lithium metal an ode host,the uncontrolled deposition is converted into a highly nucleation-induced process.On one hand,the Ag NPs distributed between the in terlayers of graphe ne can preferentially induce lithium nu cleati on and en able uniform deposition morphology of lithium between interlayers.On the other hand,the stable layered graphene structure can accommodate volume change,stabilize the interface between anode and electrolyte and inhibit dendrites formation.Therefore,the layered Ag-rGO film as anode host can reach a high Coulombic efficiency over 93.3% for 200 cycle(786 h)at a current density of 1 mA cm^(-2) for 2 mAh cm^(-2) in carbonate-based electrolyte.This work proposes a facile Gamma ray irradiation method to prepare metal/3D-skeleton structure as lithium anode host and demonstrates the potential to regulate the lithium metal deposition behaviors via manipulating the distribution of lithiophilic metal(e.g.Ag)in 3D frameworks.This may offer a practicable thinking for the subsequent design of the lithium metal anode. 展开更多
关键词 Lithium metal anode Gamma ray irradiation Ag nano-particles Inductive effect Layered structure Uniform lithium deposition
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Synthesis of New Structures and Substances in Dense Gases H2, D2 and He under Irradiation by Braking 10 MeV y-rays in Cu0.98Be0.02 Pressure Chamber
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作者 R. Wisniewski A. Yu. Didyk 《Journal of Physical Science and Application》 2016年第4期13-21,共9页
High-pressure chambers filled with gaseous hydrogen (HHPC), deuterium (DHPC) and helium (HeHPC) under different initial pressures from about I kbar up to 3 kbar were irradiated with braking γ-rays of threshold ... High-pressure chambers filled with gaseous hydrogen (HHPC), deuterium (DHPC) and helium (HeHPC) under different initial pressures from about I kbar up to 3 kbar were irradiated with braking γ-rays of threshold energy 10 MeV during varying periods of exposure at the electron beam currents 22-24μA. Upon opening of these chambers, a lot of new synthesized structures with unusual element compositions very different from the initial ones were found. The described phenomena agree well with a series of studies by authors carried out under the action of γ-rays on dense gases of hydrogen, deuterium and helium in the presence of chosen metals in the reaction chamber. 展开更多
关键词 Element composition structure gamma ray irradiation H D HE high pressure.
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X射线测量尺寸校准技术在GIS设备缺陷检测中的应用
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作者 张国宝 杨为 +5 位作者 赵恒阳 黄伟民 张磊 谢铖 杨熙 黄邦斗 《高压电器》 CAS CSCD 北大核心 2024年第6期27-32,42,共7页
在役GIS设备布置紧凑、结构复杂,现场X射线检测受空间、高度以及检测工装等限制而导致其拍摄角度受限,常出现射线束中心偏移、探测器翻转等非垂直透照情况,其X射线检测图谱出现平移、拉伸等变形,使得GIS部件尺寸的测量误差较大,部分缺... 在役GIS设备布置紧凑、结构复杂,现场X射线检测受空间、高度以及检测工装等限制而导致其拍摄角度受限,常出现射线束中心偏移、探测器翻转等非垂直透照情况,其X射线检测图谱出现平移、拉伸等变形,使得GIS部件尺寸的测量误差较大,部分缺陷难以准确定性。文中针对以上典型问题,建立了垂直透照以及X射线束中心偏移、探测器翻转、X射线束中心偏移且探测器翻转等非垂直透照情况下的几何模型,研究了X射线束中心偏移、探测器翻转角度对X射线检测图谱尺寸的影响规律,提出了不同非垂直透照情况下的X射线检测图谱校准公式,开发了一种非垂直透照下的在役GIS设备X射线检测缺陷尺寸测量校准方法,实现了全透照条件下缺陷尺寸的测量与校准。相关研究成果在现场超高压GIS隔离开关缺陷的诊断定性中取得了良好的应用成效。 展开更多
关键词 在役GIS设备 x射线检测 非垂直透照 测量尺寸校准
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Irradiation Effect of γ Rays on Diamond-Like Carbon Films
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作者 刘贵昂 王天民 《Journal of Modern Transportation》 2001年第1期75-80,共6页
Diamond like carbon films, prepared by RF glow discharge on glass substrates, were irradiated by γ rays. The as deposited and irradiated films were characterized by Raman spectroscopy, electrical resistivity, a... Diamond like carbon films, prepared by RF glow discharge on glass substrates, were irradiated by γ rays. The as deposited and irradiated films were characterized by Raman spectroscopy, electrical resistivity, and infrared transmittance. It is shown that the irradiation of the γ rays can lead to the breaking of SP 3 C H and SP 2 C H bonds, slight increasing of SP 3 C C bonds, and induced hydrogen recombination with H 2 molecules, subsequently diffusing to the surface of the films. When the γ rays irradiation dose reached 10×10 4 Gy, the numbers of SP 3 C H bonds was decreased by about 50%, the resistivity of irradiated DLC films was increased, and the diamond like character of the films became more obvious. The structure of DLC films was modified when irradiated by γ rays. The irradiation mechanisms are briefly discussed. 展开更多
关键词 ray irradiation diamond like carbon films SP 3 C H SP 2 C H and SP 3 C C bonds structure and property
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X-Ray Diffractometry and Raman Spectroscopy Investigation of Irradiated Layered III-VI Crystals
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作者 Zakhar Dmytrovych Kovalyuk Oleg Mykolayovych Sydor +4 位作者 Oksana Anatoliivna Sydor Volodymyr Grygorovych Tkachenko Igor Mykolayovych Maksymchuk Volodymyr Ivanovych Dubinko Pavlo Mykolayovych Ostapchuk 《材料科学与工程(中英文A版)》 2012年第7期537-543,共7页
关键词 x-射线衍射 拉曼光谱 电子辐照 晶体结构 照射剂量 层状晶体 晶格常数 调查结果
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Evaluation of the Effects of Irradiation of Peanut Grain by a Gamma-Ray Beam on Culture
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作者 G. Mbaye M. Soumboundou +8 位作者 L. A. D. Diouf B. Ndong A. R. Djiboune P. M. Sy S. M. Dieng M. Diouf N. N. Diouf A. Barry M. Diarra 《Open Journal of Biophysics》 2017年第3期94-100,共7页
The problems of agriculture in Senegal result in a low yield per hectare and poor seed quality contributing strongly to the decline in productivity. Mutagenesis by X- or Y-ray irradiation makes it possible to obtain g... The problems of agriculture in Senegal result in a low yield per hectare and poor seed quality contributing strongly to the decline in productivity. Mutagenesis by X- or Y-ray irradiation makes it possible to obtain genetic mutants necessary to improve production. It is in this context that we undertook this study to evaluate the effects induced on the cultivation of peanut seeds irradiated by X-rays at low doses applied in radiotherapy. X-ray irradiation of four (2, 3, 4, 5) lots of peanuts are performed with respectively 0.5, 1.5, 2 and 4 Gray using the cobalt 60 therapy device (Alcyon II). The seeding of the seeds and then the following-up of the crops during 35 days allowed us to study the parameters of germination, growth and yield. The results obtained after monitoring revealed that the irradiation did not have any significant impact on germination and would appear to temporarily inhibit the growth rate compared to the control batch. However, the decrease in weight of the harvested seeds can be explained by the absence of fertilizer during the cultivation. 展开更多
关键词 Peanuts CULTURE irradiation x-rays
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YY/T 1834—2022《X射线血液辐照设备》检测要点分析
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作者 刘博闻 金野 +1 位作者 尤寅初 王博 《品牌与标准化》 2024年第4期52-54,58,共4页
YY/T 1834—2022《X射线血液辐照设备》于2023年6月1日正式实施,为该产品的检测提供了标准化的依据。本文针对该标准的检测要点进行了分析和探讨,旨在为生产企业、设备检测人员、使用者对标准的理解提供参考。
关键词 x射线血液辐照仪 样品容器内吸收剂量 电离室法 丙氨酸剂量计-EPR法 电离室胶片联用法 不确定度
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上海光源储存环X-ray针孔相机系统设计 被引量:5
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作者 黄国庆 陈杰 +2 位作者 陈之初 冷用斌 叶恺容 《核技术》 CAS CSCD 北大核心 2010年第11期806-809,共4页
上海光源(SSRF)储存环X-ray针孔相机系统主要由X-ray引出前端、衰减片、小孔、靶片、相机、PXI控制器及图像采集等构成,数据采集处理软件在LabVIEW平台上开发,与控制系统的接口通过EPICS Shared Memory IOCcore技术实现。2009年8月开始... 上海光源(SSRF)储存环X-ray针孔相机系统主要由X-ray引出前端、衰减片、小孔、靶片、相机、PXI控制器及图像采集等构成,数据采集处理软件在LabVIEW平台上开发,与控制系统的接口通过EPICS Shared Memory IOCcore技术实现。2009年8月开始的长时间在线运行证明引出前端是安全的,在300mA运行时,测量引出窗的最高温度≤36℃。该系统设计合理、性能稳定,可在线实时测量数十μm束团横向截面尺寸,从而实现3.9nm·rad发射度的测量。 展开更多
关键词 上海光源 xray针孔相机 EPICS 发射度
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Effects on Agronomic Traits of M_1 by Pollen of Upland Cotton Irradiated by ^(60)Co-γ Ray 被引量:2
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作者 岳洁瑜 唐灿明 《Agricultural Science & Technology》 CAS 2012年第3期525-528,532,共5页
[Objective] The aim was to provide reference for research on radiation and breeding of cotton pollen through irradiating common ripe pollen grain of upland cotton by 60Co-γ Ray of varied doses. [Method] Ripe pollen g... [Objective] The aim was to provide reference for research on radiation and breeding of cotton pollen through irradiating common ripe pollen grain of upland cotton by 60Co-γ Ray of varied doses. [Method] Ripe pollen grains of upland cotton were irradiated by 60Co-γ Ray with doses of 5, 10, 15, and 20 Gy, respectively, to learn radiation effect and select appropriate dose. [Result] Most properties of M1 obviously showed variation when dose was over 10 Gy; vitality, growth, and fertility were greatly inhibited when dose was 15 Gy which was almost semi-lethal concentration, and variation species were richest at the same time, which provided materi- als for practical breeding. [Conclusion] 60Co-γ Ray of 15 Gy is more suitable for mutagenesis research on ripe pollen grains of upland cotton. 展开更多
关键词 Upland cotton 60Co-γ ray irradiation Agronomic traits Genetic variation
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Soft X ray Diagnosis on Seed Development and Observation on Seed Germination and Seedling Growth in Artificial Hybridization in Cunninghamia and Cryptomeria 被引量:1
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作者 李文钿 奇文清 +1 位作者 成小飞 胡适宜 《Acta Botanica Sinica》 CSCD 1999年第7期690-694,共5页
An intergeneric artificial hybridization was conducted between Cunninghamia R. Br. and Cryptomeria D.Don The results are as follows:1. A considerable number of hybrid seeds shed from 76 pollinated cones were ... An intergeneric artificial hybridization was conducted between Cunninghamia R. Br. and Cryptomeria D.Don The results are as follows:1. A considerable number of hybrid seeds shed from 76 pollinated cones were empty and a total of 628 looks plump. Soft X ray radiographs showed that, still and all, a majority of the “plump" seeds were embryoless (597, 95.6%) whereas some were partially developed (17,2.7%) and only a few were really full (14, 2.2%). 2. Germination test showed that all of the radiographed hybrid seeds with fully developed embryos were germinable whereas those with partially developed embryos were ungerminable. 3. Physiologically, the growth rate of hypocotyl, the date for shedding of seed coat and spreading of cotyledons, the elongation of epicotyl, and the branching of shoot of the 11 month old seedlings showed a tendency to fall behind those of the female parent; morphologically, the 11 month old hybrid seedlings with linear leaves appeared rather short, slender and weak, whereas the seedlings of the female parents with linear_lanceolate leaves appeared rather tall, stout and strong. 4. It is considered that the hybrid may be true and the crossability reveals a close phylogenetic affinity of Cunninghamia with Cryptomeria. 展开更多
关键词 Cunninghamia CRYPTOMERIA Artificial hybridization Soft x ray
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INTERFACIAL BONDING IN AS DEPOSITED AND ANNEALED Co/C SOFT X RAY MULTILAYER MIRRORS
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作者 白海力 姜恩永 +1 位作者 王存达 田仁玉 《Transactions of Tianjin University》 EI CAS 1998年第2期80-85,共6页
Interfacial bonding in as deposited and annealed Co/C soft X ray multilayer structures is investigated by X ray photo electron spectroscopy (XPS).It is found that there is interdiffusion between cobalt and carbon ... Interfacial bonding in as deposited and annealed Co/C soft X ray multilayer structures is investigated by X ray photo electron spectroscopy (XPS).It is found that there is interdiffusion between cobalt and carbon in the as deposited Co/C multilayers,and this is confirmed by structure characterization using low angle X ray diffraction (LAXD).The calculation of the chemical shifts in Co C system based on Miedemas macroscopic atom model suggests that it is impossible to detect the chemical shift experimentally in the Co C compound,which is consistent with the XPS results.The presence of metallic carbide bonding is evidenced through the nature of the carbon bonding in survey taken at Co C and C Co interfaces of annealed samples.Our results also indicate that XPS is a direct method to probe the chemical bonding at the interfaces. 展开更多
关键词 soft x ray MULTILAYERS interfacial bonding thermodynamic properties
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