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Not enough evidence to support the correlation between gamma-ray bursts and foreground galaxy clusters in the Swift Era

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Research in Astronomy and Astrophysics 2010年第6期10卷 533-540页

作者： jing Wang Jian-yan wei National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

The correlation between distant Gamma-Ray Bursts （GRBs） and foreground galaxy clusters is re-examined by using the well localized （with an accuracy down to a few arcsec） Swift/XRT GRBs. The galaxy clusters are compiled from both the X-ray selected ROSAT brightest cluster sample （BCS） and the BCS extension by requiring δ ≥ 0° and b ≥ 20°. The Swift/XRT GRBs fulfilling the above selection criteria are cross-correlated with the clusters. Both Nearest-Neighbor analysis and the angular two-point cross-correlation function show that there is not enough evidence supporting the correlation between the GRBs and foreground clusters. We suggest that the non-correlation is probably related to the GRB number-flux relation slope.

关键词： gamma rays bursts -- galaxies clusters general -- methods statistical

A pilot study of catching high-z GRBs and exploring circumburst environment in the forthcoming SVOM era

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Research in Astronomy and Astrophysics 2020年第8期20卷 211-216页

作者： jing Wang Yu-Lei Qiu Jian-yan wei Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China Key Laboratory of Space Astronomy and Technology National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

Rapid spectroscopy of GRB afterglows is an important and hard *** on the archival XSGRB spectral database,we here perform a pilot study on the afterglow's spectroscopy in the forthcoming SVOM era in two ***,our simulation indicates that the color acquired from the SVOM/VT blue and red channels is effective in discriminating between low-z(z≤3)and distant GRB candidates until z^***,by doubling the sample size,we find that the previously proposed global photoionization response of the circumburst gas to the prompt emission(i.e.,the CIV/CII-L(iso)/E2peak relationship)is roughly *** the confirmation is dissatisfactory at the large L(iso)/E2peak *** believe that this issue can be further addressed in the SVOM era by a larger spectroscopy sample,thanks to its capability of rapid identification of optical candidates of afterglow and its anti-solar pointing strategy.

关键词： gamma ray bursts:general techniques:photometric techniques:spectroscopic methods:statistical

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基于干涉和实时前馈实现三个量子节点的纠缠

原子与分子物理学报 2025年第4期42卷 113-120页

作者：刘艳红陈伟李雁翔太原师范学院物理系晋中030619 太原师范学院计算机科学与技术学院晋中030619 山西北方机械制造有限责任公司太原030009

纠缠多个空间分离的远程量子节点是构建量子信息网络的基础,不仅如此,多量子节点间的纠缠亦可应用于分布式量子计算和量子精密测量等,实现更高纠缠度的多量子节点间纠缠势在必行.文中基于干涉和实时前馈,借助于腔增强通过采用受激拉曼... 详细信息

纠缠多个空间分离的远程量子节点是构建量子信息网络的基础,不仅如此,多量子节点间的纠缠亦可应用于分布式量子计算和量子精密测量等,实现更高纠缠度的多量子节点间纠缠势在必行.文中基于干涉和实时前馈,借助于腔增强通过采用受激拉曼散射机制实现三个远距离原子系综的纠缠.该方案中只需要三套腔增强原子系统,光学谐振腔增强了光和原子之间的相互作用,使得通过受激拉曼散射产生的斯托克斯光场和反斯托克斯光场的效率得到提高,实现了高纠缠度的光与原子纠缠.在此前提下,基于斯托克斯光场的干涉和实时前馈实现三个远程原子节点间的纠缠.这种方法可以扩展到更大规模,甚至更加复杂的量子信息网络中,从而在量子信息科学中具有潜在的应用.

关键词：原子系综纠缠干涉实时前馈受激拉曼散射

Theoretical study on the exciton dynamics of coherent excitation energy transfer in the phycoerythrin 545 light-harvesting complex

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Chinese Physics B 2022年第1期31卷 631-641页

作者： Xue-yan Cui Yi-jing yan Jian-Hua wei Department of Physics&Beijing Key Laboratory of Optoelectronic Functional Materials and Micro-nano Devices Renmin University of ChinaBeijing 100872China Hefei National Laboratory for Physical Sciences at the Microscale&Department of Chemical Physics University of Science and Technology of ChinaHefei 230026China

The experimental observation of long-lived quantum coherence in the excitation energy transfer(EET)process of the several photosynthetic light-harvesting complexes at low and room temperatures has aroused hot *** challenges the common perception in the field of complicated pigment molecular systems and evokes considerable theoretical efforts to seek reasonable *** this work,we investigate the coherent exciton dynamics of the phycoerythrin 545(PE545)*** use the dissipation equation of motion to theoretically investigate the effect of the local pigment vibrations on the population transfer *** result indicates that the realistic local pigment vibrations do assist the energy *** demonstrate the coherence between different pigment molecules in the PE545 system is an essential ingredient in the EET process among various *** coherence makes the excitation energy delocalized,which leads to the redistribution of the excitation among all the chromophores in the steady ***,we investigate the effects of the complex high-frequency spectral density function on the exciton dynamics and find that the high-frequency Brownian oscillator model contributes most to the exciton dynamic *** discussions on the local pigment vibrations of the Brownian oscillator model suggest that the local heterogeneous protein environments and the effects of active vibration modes play a significant role in coherent energy transport.

关键词： exciton dynamics light-harvesting complex quantum coherence

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孕早期58例绒毛细胞培养及染色体核型分析

中国优生与遗传杂志 2018年第3期26卷 48-50页

作者：李春艳张晶李卫凯黄胜起江门市中心医院检验科细胞遗传室广东江门529070

目的探讨孕早期绒毛细胞培养染色体核型分析在产前诊断中的应用。方法对2012年3月至2016年12月在我院产科门诊就诊的58例具有产前诊断指征的孕妇,在B超引导下经腹抽取绒毛,用培养法进行绒毛细胞培养及G显带染色体核型分析;结果 58例绒... 详细信息

目的探讨孕早期绒毛细胞培养染色体核型分析在产前诊断中的应用。方法对2012年3月至2016年12月在我院产科门诊就诊的58例具有产前诊断指征的孕妇,在B超引导下经腹抽取绒毛,用培养法进行绒毛细胞培养及G显带染色体核型分析;结果 58例绒毛标本,培养成功58例,培养成功率100%;共检出染色体异常核型30例,异常率为51.72%;其中11例45,X;6例18三体;4例21三体;1例47,XXX;1例92,XXXX;1例47,XN,+mar嵌合体;1例X染色体部分重复嵌合体;2例染色体缺失;1例平衡易位。结论绒毛细胞培养及染色体核型分析方法简便可靠,成功率高,能在孕早期及时发现胎儿染色体疾病,为产前诊断提供帮助。

关键词：绒毛细胞培养染色体核型分析产前诊断

Electrochemical Study on Hydrogen Evolution and CO2 Reduction on Pt Electrode in Acid Solutions with Different pH

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Chinese Journal of Chemical Physics 2018年第5期31卷 626-634,735页

作者： jing yang Jie wei wei Chen yan-xia Chen Hefei National Laboratory for Physical Science at the Microscale and Department of Chemical Physics University of Science and Technology of ChinaHefei 230026China

Hydrogen evolution reaction(HER)is the major cathodic reaction which competes CO2 reduction reaction(CO2 RR)on Pt *** level understanding on how these two reactions interact with each other and what the key factors are of CO2 RR kinetics and selectivity will be of great help in optimizing electrolysers for CO2 *** this work,we report our results of hydrogen evolution and CO2 reduction on Pt(111)and Pt film electrodes in CO2 saturated acid solution by cyclic voltammetry and infrared *** solution with pH>2,the major process is HER and the interfacial pH increases abruptly during HER;COad is the only adsorbed intermediate detected in CO2 reduction by infrared spectroscopy;the rate for COad formation increases with the coverage of UPD-H and reaches maximum at the onset potential for HER;the decrease of COad formation under HER is attributed to the available limited sites and the limited residence time for the reduction intermediate(Had),which is necessary for CO2 adsorption and reduction.

关键词： Hydrogen evolution reaction CO2 Reduction Pt(111) Acidic solution pH effect Infrared spectroscopy

Evolution of plasticized MnO–Al2O3–SiO2-based nonmetallic inclusion in 18wt%Cr-8wt% Ni stainless steel and its properties during soaking process

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International Journal of Minerals,Metallurgy and Materials 2020年第3期27卷 328-339页

作者： jing Guo Xing-run Chen Shao-wei Han yan yan Han-jie Guo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Jiuquan Iron and Steel Group Corporation Jiayuguan 735100China Beijing Shougang Co.Ltd. Qian'an 064400China

The properties of MnO–Al2O3–SiO2-based plasticized inclusion are likely to change during soaking process due to its low melting point. In this study, the evolution of the MnO–Al2O3–SiO2-based inclusion of 18 wt%Cr-8 wt%Ni stainless steel under isothermal soaking process at 1250°C for different times was investigated by laboratory-scale experiments and thermodynamic analysis. The results showed that the inclusion population density increased at the first stage and then decreased while their average size first decreased and then increased. In addition, almost no Cr2O3-concentrated regions existed within the inclusion before soaking, but more and more Cr2O3 precipitates were formed during soaking. Furthermore, the plasticity of the inclusion deteriorated due to a decrease in the amount of liquid phase and an increase in the high-melting-pointphase MnO–Cr2O3 spinel after the soaking process. In-situ observations by high-temperature confocal laser scanning microscopy(CLSM) confirmed that liquid phases were produced in the inclusions and the inclusions grew rather quickly during the soaking process. Both the experimental results and thermodynamic analysis conclude that there are three routes for inclusion evolution during the soaking process. In particular, Ostwald ripening plays an important role in the inclusion evolution, i.e., MnO–Al2O3–SiO2-based inclusions grow by absorbing the newly precipitated smaller-size MnO–Cr2O3 inclusions.

关键词： nonmetallic inclusion soaking process Ostwald ripening stainless steel

A Blockchain Based Mobile Crowdsensing Market

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China Communications 2019年第6期16卷 31-41页

作者： Xin wei Yong yan wei Jiang jing Shen Xuesong Qiu State Key Laboratory of Networking and Switching Technology of Beijing University of Posts and Telecommunications Beijing 100876China State Grid Zhejiang Electric Power Research Institute Hangzhou 310014China Internet department of State Grid Corporation of China Beijing 100031China State Grid Henan Electric Power Company Information&Telecommunication Company Zhengzhou 450000China

Mobile crowdsensing(MCS)is an emerging pattern which means task initiators attract mobile users sensing with their own devices by some *** could exploit idle resources in low cost,while it has lots of flaws,which impede its ***,isolations between different MCS systems leads to wastage of social ***’s more,current MCS always operate in a centralized way,which causes it vulnerable and *** is a promising technology which could supply a credible and transparent *** paper construct a blockchain based MCS market and design smart contract for its *** our design,platform breaks isolation by blockchain,task initiators and mobile users manage their tasks by smart contract and bargain price with distributed *** this way,resource could be exploited better,and the market could be more ***’s more,the paper analyzes Walrasian Equilibrium(WE)in the market,and details how to deploy MCS in *** results shows that Equilibrium could be found.

关键词： mobile crowdsensing incentive mechanism blockchain Walrasian Equilibrium

Possible evidence of destroying small PAH particles by radiation from AGNs

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Research in Astronomy and Astrophysics 2015年第2期15卷 199-206页

作者： Qi-Chen Feng jing Wang Jian-yan wei National Astronomical Observatories Chinese Academy of Sciences University of Chinese Academy of Sciences

The issue of destroying small polycyclic aromatic hydrocarbon （PAH） par- ticles by radiation from AGNs is examined through optical narrow-emission line ra- tios of a sample of type II AGNs. We find that narrow-line ratios [OI]λ6300/Ha and [SII]λ6716, λ6731/Hα have prominent correlations with the PAH 11.3/7.7 ratio in our selected sample of AGNs. Because of the marginal （and in some cases no） dependence of the PAH ratio on the gas metallicity, a possible explanation for the correlations is the destruction of small PAH particles by the hard ionizing field associated with the AGNs.

关键词： infrared: ISM quasars: emission lines galaxies: active galaxies: AGN methods: statistical