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Timing and Spectral Analysis of the Black Hole X-Ray Binary MAXI J1803-298 with Insight-HXMT Data

Research in Astronomy and Astrophysics 2024年第6期24卷 209-224页

作者： ying-chen xu Jin-Lu Qu MMéndez Rui-Can Ma Long Ji Liang Zhang Yue Huang Qing-Cui Bu Li-Ming Song Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China Kapteyn Astronomical Institute University of GroningenP.O.BOX 8009700 AV GroningenThe Netherlands Dongguan Neutron Science Center Dongguan 523808China School of Physics and Astronomy Sun Yat-Sen UniversityZhuhai 519082China Institut für Astronomie und Astrophysik Kepler Center for Astro and Particle PhysicsEberhard Karls UniversitätSand 1D-72076 TübingenGermany

We present a comprehensive analysis of the 2021 outburst of MAXI J1803–298 utilizing observations of the Insight-Hard X-ray Modulation Telescope(Insight-HXMT)spanning from the low hard state to the high soft *** the Insight-HXMT data set,compared to the previous work,we identify a more prolonged presence of typeC quasi-periodic oscillations(QPOs)with centroid frequencies ranging from~0.16 to 6.3 Hz,which present correlations with the hardness ratio and the photon index of the Comptonized *** QPO frequencies less than~2 Hz,the QPO phase lags are hard(photons of 10–19 keV arrive later than those of 1–4 keV),while at higher frequencies,the lags become soft at and above~4 ***,the spectra in all Insight-HXMT observations consist of a multi-color blackbody component and a Comptonized component,as commonly observed in classical black hole X-ray *** analyze state transitions and the evolution of accretion geometry in this *** fitted inner disk radius increases abnormally during the low hard state,hypothesized to result from the corona condensing onto the inner ***,two significant drops in flux are observed during the soft intermediate state,maybe implying changes in the corona/jet and the disk,respectively.

关键词： X-rays:binaries accretion accretion disks stars:black holes

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Temporal and Spectral Characteristics of Persistent Emission and Special Bursts of Magnetar SGR J1935+2154 Based on Insight-HXMT

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Research in Astronomy and Astrophysics 2024年第6期24卷 225-233页

作者： xue-Feng Lu Li-Ming Song Ming-Yu Ge Shuang-Nan Zhang Jin-Lu Qu Ce Cai Cong-Zhan Liu cheng-Kui Li Yu-Cong Fu ying-chen xu Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsBeijing 100049China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China College of Physics and Hebei Key Laboratory of Photophysics Research and Application Hebei Normal UniversityShijiazhuang 050024China Department of Astronomy Beijing Normal UniversityBeijing 100875China

In October 2022,the magnetar SGR J1935+2154 entered the active outburst *** the episode,the InsightHXMT satellite carried out a long observation that lasted for 20 *** than 300 bursts were detected,and a certain amount of persistent radiation signals were also *** paper mainly introduces the results of persistent radiation profile folding and period search based on Insight-HXMT *** the same time,the burst phase distribution characteristics,spectral lag results of burst,the spectral characteristics of zero-lag bursts and the time-resolved spectral evolution characteristics of high-flux bursts are *** found that there is no significant delay feature during different energy bands for the bursts of SGR J1935+*** observed zero-lag burst does not have a unique *** time-resolved spectrum of the individual burst has consistent spectral types and spectral parameters at different time periods of the *** also find that the burst number phase distribution and the burst photon phase distribution have the same tendency to concentrate in specific regions of the persistent emission profile.

关键词： radiation mechanisms:general dense matter magnetic fields

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整本书阅读教学中思维可视化工具的运用

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当代教研论丛 2024年第5期10卷 70-73页

作者：陈旭英政和县教师进修学校福建南平353600

受传统应试教育模式的影响,语文阅读教学存在教学质量不高、学生缺乏阅读学习兴趣的情况,整本书阅读教学方式更适合开启学生的阅读之旅。文章认为,在整本书阅读教学中,教师从学生阅读经验的积累开始,引导学生把握阅读技巧并以此形成阅... 详细信息

受传统应试教育模式的影响,语文阅读教学存在教学质量不高、学生缺乏阅读学习兴趣的情况,整本书阅读教学方式更适合开启学生的阅读之旅。文章认为,在整本书阅读教学中,教师从学生阅读经验的积累开始,引导学生把握阅读技巧并以此形成阅读思维,可以实现学生对阅读知识的深刻认知。学生在整本书阅读教学思维可视化工具的应用过程中可以有组织地进行学习、思考交流。

关键词：整本书阅读思维可视化教学模式

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A distributed inverse iteration method for eigenvalue analysis of interconnected power systems

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Science China(Technological Sciences) 2007年第6期50卷 774-785页

作者： SHEN chen chen ying ZHANG xu State Key Laboratory of Power Systems Department of Electrical Engineering Tsinghua University Beijing 100084 China State Key Laboratory of Power Systems Department of Electrical Engineering Tsinghua University Beijing 100084 China State Key Laboratory of Power Systems Department of Electrical Engineering Tsinghua University Beijing 100084 China

Since China power grids have a hierarchical architecture in operation and man- agement, centralized computation patterns are difficult to meet the demands of small-signal-stability analysis of the bulk interconnected power systems. A dis- tributed eigenvalue algorithm derived from the inverse iteration method is pro- posed. It can not only obtain eigenvalues and eigenvectors from power system state matrix but also provide participation factors of all generators. In the comput- ing process, the algorithm only requires exchanging data of boundary nodes and a small amount of other information of different regions. Therefore, it is very suitable to be deployed in a WAN (wide area network) based distributed environment. The algorithm has been tested on an IEEE39 system.

关键词： distributed computing, eigenvalue, small signal stability, inverse iteration method

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An investigation of cellular distribution of manganese in hyperaccumlator plant Phytolacca acinosa Roxb. using SRXRF analysis

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Journal of Environmental Sciences 2006年第4期18卷 746-751页

作者： xu Xiang-hua SHI Ji-yan chen ying-xu xuE Sheng-guo WU Bei HUANG Yu-ying Department of Environmental Engineering Zhejiang University Hangzhou 310029 China Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039 China

Phytolacca acinosa Roxb. （P acinosa） is a recently discovered manganese hyperaccumulator plant from southern China. It is a good candidate for phytoremediation of manganese（Mn） polluted soil for its high biomass and fast growth. Knowledge of the tissue localization and identification of heavy metals can provide essential information on metal toxicity and bioaccumulation mechanisms. Synchrotron radiation X-ray fluorescence spectroscopy （SRXRF） microprobe was used in this study to investigate the cellular distributions of Mn and other elements in root, stem, leaf, petiole and midrib of P. acinosa. The highest Mn content was found in the vascular tissues of root, stem, petiole and midrib. Cortex in root played a key role in Mn absorption and Mn was limited in the vascular bundle during the process of transportation in stem. Moreover, Mn content in leaf epidermis was higher than that in mesophyll, which suggested that the sequestration of Mn in leaf epidermis might be one of the detoxification mechanisms of P. acinosa. The significance of other elemental （such as P, S, K, Ca, Fe, Zn and Cu） distribution patterns and the correlation with Mn were also discussed.

关键词： hyperaccumulator Phytolacca acinosa Roxb. manganese element distribution SRXRF

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Reaction site and mechanism in the UV or visible light induced TiO2 photodegradation of Orange G

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Journal of Environmental Sciences 2006年第1期18卷 180-183页

作者： YANG Shi-ying LOU Li-ping WU Xiao-na chen ying-xu Department of Environmental Engineering Zhejiang University Hangzhou 310029 China College of Environmental Science and Engineering Ocean University of China Qingdao 266003 China

For TiO2 heterogeneous reaction, the reaction site and the detailed mechanism are interesting and controversy topics. In this paper, effects of surface fluorination of TiO2 on the photocatalytic degradation of an azo dye, Orange G（OG） under UV or visible light irradiation were investigated, and the possible reaction site and mechanism were elucidated. The adsorption of OG on TiO2 was nearly inhibited by fluoride but its UV light induced photodegradation rate was greatly increased by a factor of about 2.7, which was due to the more generated free hydroxyl radicals. It supported the views that fluoride could desorb the oxidant species from surface and that the reaction sites could move to the bulk solution. In TiO2/Vis system, the observed inhibition effects of fluorination could be interpreted by the competitive adsorption, which provided additional evidences that the visible light sensitized photodegradation of dye pollutants on the catalyst surface.

关键词： photocatalytic degradation mechanism adsorption fluorination dye pollutants

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Involvement of chloride anion in photocatalytic process

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Journal of Environmental Sciences 2005年第5期17卷 761-765页

作者： YANG Shi-ying chen ying-xu LOU Li-ping WU Xiao-na Department of Environmental Engineering Zhejiang University Hangzhou 310029 China College of Environmental Sciences anti Engineering Ocean University of China Qingdao 266003 China

The effect of Cl^- on photocatalytic degradation（PCD） of pollutants is an important factor since it is ubiquitous in nature. In general, Cl^- showed an inhibition on photodegradation due to its scavenging HO- radicals. In this paper, experiments were carried out to examine the effects of CI on the PCD of Methylene Blue （MB） and Orange II （OII） in aqueous TiO2 suspensions under UV light illumination. It was found that low concentration of Cl^- （〈 0.01 mol/L） showed little influence on both dyes, however, high concentration of Cl^- （〉 0.10 mol/L） had a very different influence on the decolorization of dyes： a significant inhibition for MB but a great promotion for Oll. In the presence of 0.50 mol/L Cl^- , the rate decreased by 70% for MB while increased 7.5-fold for Oll. Furthermore, two bands in the ultraviolet region of Oll were rapidly broken down. The proposed mechanism was discussed in detail.

关键词： photocatalytic degradation TiO2 dye pollutants chloride ion mechanism

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Environmental damage costs from fossil electricity generation in China, 2000~2003

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第11期8卷 1816-1825页

作者： ZHANG Qing-yu WEI Yu-mei chen ying-xu GUO Hui Department of Environmental Engineering Zhejiang University Hangzhou 310027 China

Electricity consumption increases rapidly with the rapid development of China. The environmental damage costs of electricity generation are very important for both policy analysis and the proper management of the environment. A method was developed in this work to estimate gross environmental damage costs according to emission inventory and environmental cost factors, and to extend the costs from provincial to national level with population density. In this paper, sulfur dioxide (SO2), nitrogen oxides (NOx), particulate matter less than 10 μm in diameter (PM10), and carbon dioxide (CO2) from fossil fired power plants over 6000 kW were selected as index pollutants to quantify the environmental costs of damages on human health and global warming. With the new developed method, environmental damage costs, caused by 3 types of fired power plants in 30 provinces and 6 economic sectors during the years 2000 to 2003, were evaluated and analyzed. It can be seen that the calculated total national environmental damage costs of electricity have rapidly increased from 94930.87×106 USD in 2000 to about 141041.39×106 USD in 2003, with an average annual growth rate of 14.11%. Environmental damage costs of SO2, NOx, PM10, and CO2 are 69475.69×106, 30079.29×106, 28931.84×106, and 12554.57×106 USD and account for 49.26%, 21.33%, 20.51%, and 8.90% of total environmental costs in fossil electricity generation, respectively. With regard to regional distribution, external costs caused by fossil electricity generation are mainly concentrated in the more populated and industrialized areas of China, i.e., the Eastern Central and Southeastern areas.

关键词： Environmental damage costs Fossil electricity generation Emission inventory Uncertainty analysis

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Heavy metal availability and impact on activity of soil microorganisms along a Cu/Zn contamination gradient

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Journal of Environmental Sciences 2007年第7期19卷 848-853页

作者： WANG Yuan-peng SHI Ji-yan LIN Qi chen Xin-cai chen ying-xu Department of Chemical and Biochemical Engineering College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China. Department of Environmental Science and Technology Zhejiang University Hangzhou 310029 China

All the regulations that define a maximum concentration of metals in the receiving soil are based on total soil metal concentration. However, the potential toxicity of a heavy metal in the soil depends on its speciation and availability. We studied the effects of heavy metal speciation and availability on soil microorganism activities along a Cu/Zn contamination gradient. Microbial biomass and enzyme activity of soil contaminated with both Cu and Zn were investigated. The results showed that microbial biomass was negatively affected by the elevated metal levels. The microbial biomass-C （Cmic）/organic C （Corg） ratio was closely correlated to heavy metal stress. There were negative correlations between soil microbial biomass, phosphatase activity and NH4NO3 extractable heavy metals. The soil microorganism activity could be predicted using empirical models with the availability of Cu and Zn. We observed that 72% of the variation in phosphatase activity could be explained by the NH4NO3-extractable and total heavy metal concentration. By considering different monitoring approaches and different viewpoints, this set of methods applied in this study seemed sensitive to site differences and contributed to a better understanding of the effects of heavy metals on the size and activity of microorganisms in soils. The data presented demonstrate the relationship between heavy metals availability and heavy metal toxicity to soil microorganism along a contamination gradient.

关键词： heavy metals availability speciation activity soil microorganism

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Uptake and accumulation of phenanthrene and pyrene in spiked soils by Ryegrass(Lolium perenne L.)

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Journal of Environmental Sciences 2005年第5期17卷 817-822页

作者： xu Sheng-you chen ying-xu LIN Qi WU Wei-xiang xuE Sheng-guo SHEN Chao-feng Department of Environmental Engineering Zhejiang University Hangzhou 310029 China Department of Resource and Environment Huangshan University Huangshan 245000 China

Phytoremediation has long been recognized as a cost-effective method for the removal of polycyclic aromatic hydrocarbons （PAHs） from soil. A study was conducted to investigate the uptake and accumulation of PAHs in root and shoot of Lolium perenne L. Pot experiments were conducted with series of concentrations of 3.31-378.37 mg/kg for phenanthrene and those of 4.22-365.38 mg/kg for pyrene in a greenhouse. The results showed that both ryegrass roots and shoots did take up PAHs from spiked soils, and generally increased with increasing concentrations of PAH in soil. Bioconcentration factors（BCFs） of phenanthrene by shoots and roots were 0.24- 4.25 and 0.17-2.12 for the same treatment. BCFs of pyrene by shoots were 0.20-1.5, except for 4.06 in 4.32 mg/kg treatment, much lower than BCFs of pyrene by roots （0.58-2.28）. BCFs of phenanthrene and pyrene tended to decrease with increasing concentrations of phenanthrene and pyrene in soil. Direct uptake and accumulation of these compounds by Lolium perenne L. was very low compared with the other loss pathways, which meant that plant-promoted microbial biodegradation might be the main contribution to plant-enhanced removal of phenanthrene and pyrene in soil. However, the presence of Lolium perenne L. significantly enhanced the removal of phenanthrene and pyrene in spiked soil. At the end of 60 d experiment, the extractable concentrations of phenanthrene and pyrene were lower in planted soil than in non-planted soil, about 83.24%-91.98% of phenanthrene and 68.53%-84.10% of pyrene were removed from soils, respectively. The results indicated that the removal of PAHs in contaminated soils was a feasible approach by using Lolium perenne L.

关键词： phytoremediation polycyclic aromatic hydrocarbons(PAHs) phenanthrene and pyrene uptake and accumulation

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