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Comparison of simulated backgrounds with in-orbit observations for HE, ME, and LE onboard Insight-HXMT 期刊论文  OAI收割
Astrophysics and Space Science, 2020, 卷号: 365, 页码: 158
作者:  HXMT
  |  收藏  |  浏览/下载：53/0  |  提交时间：2022/02/08
Insight-HXMT  Geant4 simulation  Background observation  Astrophysics  - Instrumentation and Methods for Astrophysics  Abstract: Insight-HXMT, the first X-ray astronomical satellite in China, aims to reveal new sources in the Galaxy and to study fundamental physics of X-ray binaries from 1 to 250 keV. It has three collimated telescopes, the High Energy X-ray telescope (HE), the Medium Energy X-ray telescope (ME), and the Low Energy X-ray telescope (LE). Before the launch, in-orbit backgrounds of these three telescopes had been estimated through Geant4 simulation, in order to investigate the instrument performance and the achievement of scientific goals. In this work, these simulated backgrounds are compared with in-orbit observations. Good agreements are shown for all three telescopes. For HE, (1) the deviation of the simulated background rate after two years of operation in space is 5 % from the observation  (2) the total background spectrum and the relative abundance of the 67 keV line show long-term increases both in simulations and observations. For ME, (1) the deviation of simulated background rate is within 15 % from the observation, and (2) there are no obvious long-term increase features in the background spectra of simulations and observations. For LE, the background level given by simulations is also consistent with observations. The consistencies of these comparisons validate that the Insight-HXMT mass model, i.e., space environment components and models adopted, physics processes selected, and detector constructions built, is reasonable. However, the line features at 7.5 and 8.0 keV, which are obvious in the observed spectra of LE, are not evident in simulations. This might result from uncertainties in the LE constructions.  
碳氮稳定同位素比值在潮间带大型底栖动物组织间差异性研究 期刊论文  OAI收割
海洋学报, 2019, 卷号: 41, 期号: 4, 页码: 74-82
作者:  李宝泉
  |  收藏  |  浏览/下载：33/0  |  提交时间：2020/06/17
潮间带  大型底栖动物  碳氮稳定同位素  食源和营养级分析  采样部位选取  intertidal zone  macrobenthos  carbon and nitrogen stable isotopes  food sources and trophic levels study,sampling parts  The technique of stable isotope analysis has been widely applied for the field of food web studies in recent years.However,few researches concerned about the impacts of different tissues used for analysis on the food web building.With the purpose of accuracy and comparability in the food web studies,the sampling tissues should be standardized.In this study,10macrobenthic species from the intertidal zone of the Yellow River Delta and Yantai were chosen as the target object to test the isotopic characteristic variations ofdelta~(13)C anddelta15 N at different body parts (whole bodies,muscles and gills).Our results show thatdelta~(13)C anddelta15 N values vary in different sampling tissues for most species,which indicates the different tissues used for analysis impact the food web building.To achieve a more accuracy and comparability result,suitable tissue should be primarily chosen for their food sources and trophic levels analysis.Namely,when the organism as predator,their muscles should first be chosen,for examples,adductor and foot muscles of mollusks,leg muscles of crabs and back muscles of fishes  when the organism as prey, most of their tissues,except for indigestible part(for polychaetes,the digestive tract contents should be removed) should be chosen for analysis on food sources and trophic levels of the secondary consumer,for example,whole soft parts of mollusks,the mixture of muscles and gills of crabs.  
Research Progress of a New Type of potential anti-cancer drugs:ent-kaurane diterpenoids 期刊论文  OAI收割
中国化学会第9届天然有机化学学术会议论文集, 2012, 页码: 1
普建新
收藏  |  浏览/下载：31/0  |  提交时间：2013/05/03