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Statistical properties of the photoelectron energy spectrum generated by an intense laser pulse and a continuous X-ray
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作者 葛愉成 葛湘洁 何海萍 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第11期325-331,共7页
This study shows that the photoelectron energy spectrum generated by an intense laser pulse in the presence of a continuous X-ray has interesting and useful statistical properties. The total photoionization production... This study shows that the photoelectron energy spectrum generated by an intense laser pulse in the presence of a continuous X-ray has interesting and useful statistical properties. The total photoionization production is linearly propor- tional to the time duration of the laser pulse and the square of the beam size. The spectral double energy-integration is an intrinsic value of the laser-assisted X-ray photoionization, which linearly depends on the laser intensity and which quantita- tively reflects the strengths of the laser-field modulation and the quantum interference between photoelectrons. The spectral energy width also linearly depends on the laser intensity. These linear relationships suggest new methods for the in-situ measurement of laser intensity and pulse duration with high precision. 展开更多
关键词 laser intensity pulse duration X-ray-boosted photoionization statistical properties of photoelec-tron energy spectrum
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Characteristic Period Value of the Seismic Design Response Spectrum of UHV Electrical Equipment
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作者 You Hongbing Zhao Fengxin You He 《Earthquake Research in China》 CSCD 2015年第1期117-127,共11页
Characteristic period is an important parameter of the seismic design response spectrum. There is important theoretical significance and engineering application value to the study of the characteristic period of seism... Characteristic period is an important parameter of the seismic design response spectrum. There is important theoretical significance and engineering application value to the study of the characteristic period of seismic design response spectrum of ultra high voltage (UHV) electrical equipment. In this paper, 1448 horizontal earthquake records within the world scope including the United States and Japan for Site Class m were analyzed. Results show that both magnitude and epicentral distance have great influence on the characteristic period. About 80 % of characteristic periods of strong earthquake records are about 0. 9s. Statistical analysis was conducted on the seismic hazard assessment results of 312 projects of China in recent years, and it is found that about 70 % of characteristic periods are about 0. 9s. Combined with the related code comparison and analysis, it is suggested that the characteristic period of the seismic design response spectrmn of UHV electrical equipment should select 0. 9s in order to effectively guarantee the seismic safety of UHV electrical equipment. 展开更多
关键词 UHV electrical equipment Seismic design response spectrum Characteristicperiod statistical analysis
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Insights into the characteristics of cancer incidence in China
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作者 Jiahui Wang Xuping Yang +3 位作者 Wenhui Shen Yueyu Huang Weimin Mao An Zhao 《Science China(Life Sciences)》 2025年第5期1512-1515,共4页
The morbidity and mortality of cancer in China have undergone significant changes over the past few decades,which is a reflection of alterations in cancerrelated factors,such as pace of life,living habits,and level of... The morbidity and mortality of cancer in China have undergone significant changes over the past few decades,which is a reflection of alterations in cancerrelated factors,such as pace of life,living habits,and level of related medical treatment.Consequently,it is crucial to analyze the changes in the spectrum of cancer statistics in China and compare them with international values over time to assess and update cancer prevention and treatment strategies. 展开更多
关键词 analyze changes spectrum cancer statistics morbidity mortality changes decades cancer statistics cancer incidence LIFESTYLE living habits prevention treatment strategies
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Spectral properties of Fermi/GBM gamma-ray bursts and the GeV emission detection rate with Fermi/LAT 被引量:2
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作者 LV HouJun LIANG EnWei TONG XiaoFeng 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2010年第S1期73-77,共5页
With a sample of 58 Fermi/GBM GRBs detected before 2009 May,we compare the spectral properties of GBM GRBs with those detected by CGRO/BTASE and HETE-2.Our results show that the spectral index distributions are very c... With a sample of 58 Fermi/GBM GRBs detected before 2009 May,we compare the spectral properties of GBM GRBs with those detected by CGRO/BTASE and HETE-2.Our results show that the spectral index distributions are very consistent with those observed by BATSE.However,the Ep distribution is quite different from that observed with BATSE and HETE-2.The GBM GRBs tend to be softer than the BATSE sample,but harder than the HETE-2 sample.This may be due to the instrumental selection effects and artificial sample effect on the BATSE sample.The distribution of the pseudo redshifts derived from the luminosity indicator based on the Amati-relation shows rough consistency with the spectroscopic redshifts of Swift GRBs.We estimate the detection rate of GBM GRBs with LAT based on the observed spectrum in the GBM band,and the inferred burst ratio of LAT detection with over 5 photons to GBM detection is 6%,yielding a detection rate pf 12 GRBs/yr with over 5 photons in the 1-300 GeV band.This is roughly consistent with the results in the first half year of Fermi operation.The low detection rate compared with theoretical predictions is a key for revealing the radiation mechanisms and particle acceleration of the prompt gamma-rays. 展开更多
关键词 gamma-ray bursts high energy phenomenon spectrum statistics
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