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Comparison of dark energy models:A perspective from the latest observational data

中国科学：物理学、力学、天文学英文版 2010年第9期53卷 1631-1645页

作者： li miao1,2.li xiaodong2.3 & zhang xin1,4 1kavli institute for theoretical physics china,chinese academy of sciences,beijing 100190,china 2Key Laboratory of Frontiers in theoretical physics,institute of theoretical physics,chinese academy of sciences,beijing 100190,china 3Interdisciplinary Center for theoretical Study,University of Science and Technology of china,Hefei 230026,china 4Department of physics,College of sciences,Northeastern University,Shenyang 110004,china 1. kavli institute for {2. physics china Chinese Academy of Sciences Beijing 100190 China2. Key Laboratory of Frontiers in Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100190 China3. Interdisciplinary Center for Theoretical Study University of Science and Technology of China Hefei 230026 China4. Department of Physics College of Sciences Northeastern University Shenyang 110004 China

We compare some popular dark energy models under the assumption of a flat universe by using the latest observational data including the type Ia supernovae Constitution compilation,the baryon acoustic oscillation measurement from the Sloan Digital Sky Survey,the cosmic microwave background measurement given by the seven-year Wilkinson Microwave Anisotropy Probe observations and the determination of H0 from the Hubble Space *** comparison statistics such as the Bayesian and Akaike information criteria are applied to assess the worth of the *** statistics favor models that give a good fit with fewer *** on this analysis,we find that the simplest cosmological constant model that has only one free parameter is still preferred by the current *** other dynamical dark energy models,we find that some of them,such as the αdark energy,constant w,generalized Chaplygin gas,Chevalliear-Polarski-linder parametrization,and holographic dark energy models,can provide good fits to the current data,and three of them,namely,the Ricci dark energy,agegraphic dark energy,and Dvali-Gabadadze-Porrati models,are clearly disfavored by the data.

关键词： dark energy models observational constraints model comparison information criteria

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Single-atom-mediated electron islands boost photocatalytic CO_(2.chemical fixation

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Science china Chemistry 2024年第7期67卷 2292-2299页

作者： Shu Shang Lei li xin He Hui Wang lirong Zheng Wei Shao xiaodong zhang Yi Xie Hefei National Research Center for Physical sciences at the Microscale University of Science and Technology of ChinaHefei 230026China institute of Energy Hefei Comprehensive National Science CenterHefei 230031China beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China School of Chemistry and Chemical Engineering Hefei Normal UniversityHefei 230031China

Photocatalytic cycloadditions of CO_(2.with epoxides are emerging as a significant platform for the green synthesis of valuable carbonates,where efficient catalytic systems with spatially separated charge carriers are ***,a single p-block metal atom is proposed to be a candidate for photogenerated electron localization on a metal oxide *** taking the Bi single-atom supported on ZnO nanosheet(Bi1/ZnO)as an example,we show that the Bi atom plays the role of an electron island in the sea of delocalized holes within ***,the as-formed electron island could readily promote the rate-determining ring-opening process of cycloaddition *** from the unique spatially separated electrons and holes,the Bi1/ZnO achieves a high yield of cyclic carbonates with almost 100%*** study provides a pioneering strategy for enhancing the performances of photocatalytic CO_(2.chemical fixation.

关键词： electron islands CO_(2.photofixation photogenerated charge carriers

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Research on the knee region of cosmic ray by using a novel type of electron-neutron detector array

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Frontiers of physics 2024年第4期19卷 13-24页

作者： Bing-Bing li xin-Hua Ma Shu-Wang Cui Hao-Kun Chen Tian-Lu Chen Danzengluobu Wei Gao Hai-Bing Hu Denis Kuleshov Kirill Kurinov Hu liu Mao-Yuan liu Ye liu Da-Yu Peng Yao-Hui Qi Oleg Shchegolev Yuri Stenkin li-Qiao Yin Heng-Yu zhang liang-Wei zhang College of physics Hebei Normal UniversityShijiazhuang 050024China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China TIANFU Cosmic Ray Research Center Chengdu 610000China College of Science Tibet UniversityLhasa 850000China Key Laboratory of Comic Rays Ministry of EducationTibet UniversityLhasa 850000China institute for Nuclear Research of the Russian academy of {2. Moscow 117312Russia School of Physical Science and Technology Southwest Jiaotong UniversityChengdu 610031China School of Management Science and Engineering Hebei University of Economics and BusinessShijiazhuang 050061China Moscow institute of physics and Technology Moscow 141700Russia

By accurately measuring composition and energy spectrum of cosmic ray,the origin problem of so called“knee”region(energy>one PeV)can be ***,up to the present,the results of the spectrum in the knee region obtained by several previous experiments have shown obvious differences,so they cannot give effective evidence for judging the theoretical models on the origin of the ***,the Large High Altitude Air Shower Observatory(LHAASO)has reported several major breakthroughs and important results in astro-particle physics *** on its advantages of wide-sky survey,high altitude location and large area detector arrays,the research content of LHAASO experiment mainly includes ultra high-energy gamma-ray astronomy,measurement of cosmic ray spectra in the knee region,searching for dark matter and new phenomena of particle physics at higher *** electron and thermal neutron detector(EN-Detector)is a new scintillator detector which applies thermal neutron detection technology to measure cosmic ray extensive air shower(EAS).This technology is an extension of *** EN-Detector Array(ENDA)can highly efficiently measure thermal neutrons generated by secondary hadrons so called“skeleton”of *** this paper,we perform the optimization of ENDA configuration,and obtain expectations on the ENDA results,including thermal neutron distribution,trigger efficiency and capability of cosmic ray composition *** obtained real data results are consistent with those by the Monte Carlo simulation.

关键词： cosmic ray EAS knee region LHAASO ENDA

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Angular distribution of terahertz emission from laser interactions with solid targets

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Science china(Information sciences) 2012年第1期55卷 43-48页

作者： DU Fei1,li Chun1,ZHOU Mulin1,WANG WeiMin1,SU LuNing1,ZHENG Yi1,GE XuLei1,li YuTong1,MA JingLong1,liU XiaoLong1,zhang Lu1,SHENG ZhengMing1,2.CHEN liMing1,LU xin1,DONG Quanli1,WANG ZhaoHua1,WEI ZhiYi1&zhang Jie1,2.beijing National Laboratory of Condensed Matter physics,institute of physics,chinese academy of sciences,beijing 100190,china 2.ey Laboratory for Laser Plasmas(Ministry of Education)and Department of physics,Shanghai Jiao Tong University,Shanghai 2.02.0,china 1. beijing National Laboratory of Condensed Matter physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China2. Key Laboratory for Laser Plasmas (Ministry of Education) and Department of Physics Shanghai Jiao Tong University Shanghai 200240 China

Intense femtosecond laser-plasma interactions can produce high power terahertz *** our experiment,the polished copper target was irradiated by a p-polarized laser with intensity of more than 1018 W/cm2.at an incident angle of 67.5 from the target *** THz energy from three dierent detection angles is *** maximum emission is found in the direction at an angle of 45 to the laser backward direction,which is more than one order of magnitude higher than in the other two directions.A simple theoretical model has been established to explain the measurements.

关键词： terahertz emission laser solid interactions angular distribution

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A draft sequence of the rice (Oryza sativa ssp. indica) genome

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chinese Science Bulletin 2001年第23期46卷 1937-1942页

作者： YU Jun, HU Songnian, WANG Jun,li Songgang WONG Ka-Shu Gane, liU Bin,DENG Yajun, DAI li, ZHOU Yan,zhang Xiuqing, CAO Mengliang, liU Jing,SUN Jiandong , TANG Jiabin, CHEN Yanjiong,HUANG Xiaobing, liN Wei, YE Chen, TONG Wei,CONG lijuan, GENG Jianing, HAN Yujun, li lin,li Wei, HU Guangqiang, HUANG Xiangang,li Wenjie, li Jian, liU Zhanwei, li Long,liU Jianping, Ql Qiuhui, liU Jinsong, li li,WANG Xuegang, LU Hong, WU Tingling,ZHU miao, Nl Peixiang, HAN Hua, DONG Wei,REN Xiaoyu, FENG Xiaoli, GUI Peng,li Xianran, WANG Hao, XU xin, ZHAI Wenxue,XU Zhao, zhang Jinsong, HE Sijie,zhang Jianguo, XU Jichen, zhang Kunlin,ZHENG Xianwu, DONG Jianhai, ZENG Wanyong,TAO lin, CHEN Xuewei, HE Jun, liU Daofeng,TIAN Wei, TIAN Chaoguang, XIA Hongai,li Gang, GAO Hui, li Ping, CHEN Wei ,WANG Xudong, zhang Yong, HU Jianfei,WANG Jing, liU Song, YANG Jian,zhang Guangyu, XIONG Yuqing, li Zhijie,MAO Long, ZHOU Chengshu, ZHU Zhen,CHEN Runsheng, HAO Bailin,ZHENG Weimou, CHEN Shouyi, QUO Wei,li Guojie, liU Siqi, HUANG Guyang,TAO Ming, WANG Jian, ZHU lihuang,YUAN Longping& YANG Huanmingbeijing Genomics institute/Center of Genomics & Bioinformatics, chinese academy of sciences, beijing 101300, china Hangzhou Genomics institute/institute of Bioinformatics of Zhejiang University/Key Laboratory of Bioinformatics of Zhejiang Province, Hangzhou 310007, china institute of Genetics, chinese academy of sciences, beijing 100101, china National Hybrid Rice R & D Center, Changsha 410125, china Laboratory of Bioinformatics, institute of Biophysics, chinese academy of sciences, beijing 100101, china College of life sciences, Peking University, beijing 100871, china institute of theoretical physics, chinese academy of sciences, beijing 1Q0080, china Digital china Ltd., beijing 100080, china institute of Computing Technology, chinese academy of sciences, beijing 100080, china Medical College, Xi’an Jiaotong University, Xi’an 710061, chinaThese authors contributed equally to this work.Corresponding author.Corresponden beijing Genomics institute/Center of Genomics & Bioinformatics Chinese Academy of Sciences Beijing China Hangzhou Genomics institute/institute of Bioinformatics of Zhejiang University/Key Laboratory of Bioinformatics of Zhejiang Province Hangzhou China College of life sciences Peking University Beijing China Medical College Xi’an Jiaotong University Xi’an China institute of Genetics Chinese Academy of Sciences Beijing China Laboratory of Bioinformatics Institute of Biophysics Chinese Academy of Sciences Beijing China National Hybrid Rice R & D Center Changsha China institute of theoretical {2. Chinese Academy of Sciences Beijing China Digital china Ltd. Beijing China institute of Computing Technology Chinese Academy of Sciences Beijing China

The sequence of the rice genome holds fundamental information for its biology, including physiology, genetics, development, and evolution, as well as information on many beneficial phenotypes of economic significance. Using a "whole genome shotgun" approach, we have pro-duced a draft rice genome sequence of Oryza sativa ssp. in-dica, the major crop rice subspecies in china and many other regions of Asia. The draft genome sequence is constructed from over 4.3 million successful sequencing traces with an accumulative total length of 2.14.9 Mb. The initial assembly of the non-redundant sequences reached 409.76 Mb in length, based on 3.30 million successful sequencing traces with a total length of 1797.4 Mb from an indica variant cultivar 93-11, giving an estimated coverage of 95.2.% of the rice genome with an average base accuracy of higher than 99%. The coverage of the draft sequence, the randomness of the sequence distribution, and the consistency of BIG-ASSEM-BLER, a custom-designed software package

关键词： rice genome draft sequences.

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Dark energy and fate of the Universe

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Science china(physics,Mechanics & Astronomy) 2012年第7期55卷 1330-1334页

作者： li xiaodong WANG Shuang HUANG QingGuo {2. xin li miao Department of Modern physics University of Science and Technology of ChinaHefei 230026China institute of theoretical {2. Chinese Academy of SciencesBeijing 100190China Key Laboratory of Frontiers in theoretical physics Chinese Academy of SciencesBeijing 100190China Department of physics College of SciencesNortheastern UniversityShenyang 110004China Center for High Energy physics Peking UniversityBeijing 100080China

We explore the ultimate fate of the Universe by using a divergence-free parametrization for dark energy w（z）=w0＋wa, [In（2.＋ z） / （1 ＋ z） - In 2. . Unlike the Chevallier-Polarski-linder parametrization, this parametrization has well behaved, bounded behavior for both high redshifts and negative redshifts, and thus can genuinely cover many theoretical dark energy models. Alter constraining the parameter space of this parametrization by using the current cosmological observations, we find that, at the 95.4% confidence level, our Universe can still exist at least 16.7 Gyr before it ends in a big rip. Moreover, for the phantom energy dominated Universe, we find that a gravitationally bound system will be destroyed at a time t = P√2. 1 ＋ 3w（ 1）] / [6π] 1 ＋ w（-1）｜], where P is the period of a circular orbit around this system, before the big rip.

关键词： dark energy dynamical evolution fate of the Universe

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Testing modified gravity models with recent cosmological observations

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Science china(physics,Mechanics & Astronomy) 2012年第12期55卷 2244-2258页

作者： zhang WenShuai CHENG Cheng HUANG QingGuo li {2. li Song li xiaodong WANG Shuang Department of Modern physics University of Science and Technology of ChinaHefei 230026China institute of theoretical {2. Chinese Academy of SciencesBeijing 100190China kavli institute for {2. physics china Chinese Academy of SciencesBeijing 100190China State Key Laboratory of theoretical physics Chinese Academy of SciencesBeijing 100190China Interdisciplinary Center for theoretical Study University of Science and Technology of ChinaHefei 230026China

We explore the cosmological implications of five modified gravity(MG) models by using the recent cosmological observational data,including the recently released SNLS3 type Ia supernovae sample,the cosmic microwave background anisotropy data from the Wilkinson Microwave Anisotropy Probe 7-yr observations,the baryon acoustic oscillation results from the Sloan Digital Sky Survey data release 7,and the latest Hubble constant measurement utilizing the Wide Field Camera 3 on the Hubble Space *** MG models considered include the Dvali-Gabadadze-Porrati(DGP) model,two f(R) models,and two f(T) *** find that compared with the ΛCDM model,MG models can not lead to an appreciable reduction of the χ 2.*** analysis of AIC and BIC shows that the simplest cosmological constant model(ΛCDM) is still the most preferred by the current data,and the DGP model is strongly *** addition,from the observational constraints,we also reconstruct the evolutions of the growth factor in these *** find that the current available growth factor data are not enough to distinguish these MG models from the ΛCDM model.

关键词： modified gravity cosmic acceleration dark energy experiment growth factor

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Calibration of the cryogenic measurement system of a resonant haloscope cavity

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chinese physics C 2024年第7期48卷 31-37页

作者：贺冬樊洁高昕高宇 Nick Houston 姬忠庆金贻荣李闯李金勉李田军刘世航牛家树彭智慧孙亮孙铮王佳卫镨先吴利娜相忠诚杨峤立张驰张文星张欣郑东宁郑瑞丰周建勇 Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Key Laboratory for Matter Microstructure and Function of Hunan ProvinceDepartment of Physics and Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal UniversityChangsha 410081China institute of physics Chinese Academy of SciencesBeijing 100190China College of physics Sichuan UniversityChengdu 610065China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China institute of theoretical {2. Faculty of ScienceBeijing University of TechnologyBeijing 100124China beijing academy of Quantum Information {2. Beijing 100193China College of Mechanical and Electrical Engineering Wuyi UniversityNanping 354300China CAS Key Laboratory of theoretical physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical sciences University of Chinese Academy of SciencesBeijing 100049China institute of theoretical {2. Shanxi UniversityTaiyuan 030006China College of physics and Optoelectronic Engineering Department of PhysicsJinan UniversityGuangzhou 510632China School of sciences Xi'an Technological UniversityXi'an 710021China Tsung-Dao Lee institute and School of physics and Astronomy Shanghai Jiao Tong University800 Dongchuan RoadShanghai 200240China National Astronomical Observatories Chinese Academy of Sciences20ADatun RoadChaoyang DistrictBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

Possible light bosonic dark matter interactions with the Standard Model photon have been searched using microwave resonant *** this paper,we describe the cryogenic readout system calibration of a 7.138 GHz copper cavity with a loaded quality factor Q_(1)=10^(4)whose operation at a temperature of 2. mK is based on a dilution *** readout system consists of High Electron Mobility Transistors working as cryogenic amplifiers at 4 K,plus room-temperature amplifiers and a spectrum analyzer for signal power *** tested the system with a superconducting two-level system based on a single-photon source in the microwave frequency *** obtained an overall 95.6 dB system gain and–71.4 dB attenuation in the cavity's input *** effective noise temperature of the measurement system is 7.5 K.

关键词： dark matter superconducting two-level system Mollow triplet

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半导体缺陷的电子结构计算方法研究进展

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物理学报 2024年第6期73卷 34-47页

作者：李晨慧张陈蔡雪芬张才鑫袁嘉怡邓惠雄中国科学院半导体研究所超晶格国家重点实验室北京100083 中国科学院大学材料科学与光电工程中心北京100049

半导体材料的掺杂与缺陷调控是实现其应用的重要前提.基于密度泛函理论的第一性原理缺陷计算为半导体的掺杂与缺陷调控提供了重要的理论指导.本文介绍了第一性原理半导体缺陷计算的基本理论方法的相关发展.首先,介绍半导体缺陷计算的基... 详细信息

半导体材料的掺杂与缺陷调控是实现其应用的重要前提.基于密度泛函理论的第一性原理缺陷计算为半导体的掺杂与缺陷调控提供了重要的理论指导.本文介绍了第一性原理半导体缺陷计算的基本理论方法的相关发展.首先,介绍半导体缺陷计算的基本理论方法,讨论带电缺陷计算中由周期性边界条件引入的有限超胞尺寸误差,并展示相应的修正方法发展.其次,聚焦于低维半导体中的带电缺陷计算,阐述凝胶模型下带电缺陷形成能随真空层厚度发散的问题,并介绍为解决这一问题所引入的相关理论模型.最后,简单介绍了缺陷计算中的带隙修正方法及光照非平衡条件下掺杂与缺陷调控理论模型.这些工作可以为半导体,特别是低维半导体,在平衡或非平衡条件下的缺陷计算提供指导,有助于后续半导体中的掺杂和缺陷调控工作的进一步发展.

关键词：半导体缺陷计算镜像电荷修正低维半导体缺陷物理非平衡掺杂

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地理时空数字化底座理论框架构建与应用实践

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地球信息科学学报 2024年第4期26卷 799-830页

作者：吴田军骆剑承李曼嘉张静赵馨胡晓东左进闵帆王玲玉黄启厅长安大学土地工程学院西安710064 中国科学院空天信息创新研究院遥感科学国家重点实验室北京100101 中国科学院大学资源与环境学院北京100049 贵州师范大学地理与环境科学学院/喀斯特研究院贵阳550001 浙江科技学院信息与电子工程学院杭州310023 天津大学建筑学院天津300072 西南石油大学计算机科学学院成都610500 贵州轻工职业技术学院信息工程系贵阳550025 广西农业科学院农业科技信息研究所南宁530007

随着高质量发展成为全面建设社会主义现代化国家的首要任务,地理时空信息支撑国家和地方社会经济发展的重要性被提到新的高度。本文面向高质量发展对地理时空信息赋能提出的迫切需求,先从复杂地表系统表达、时空不确定性分析、地理空间... 详细信息

随着高质量发展成为全面建设社会主义现代化国家的首要任务,地理时空信息支撑国家和地方社会经济发展的重要性被提到新的高度。本文面向高质量发展对地理时空信息赋能提出的迫切需求,先从复杂地表系统表达、时空不确定性分析、地理空间智能计算等视角出发,全面综述地理时空表达计算理论方法的研究现状,进而以解构复杂地表、解析精准参数为问题驱动,提出“地理时空数字化底座”的相关理论思考与研究思路,概述了其中的基本概念与技术要点,重点分析了复杂地表系统的多重表达与知识关联、空间形态约束谱序特征重建的不确定性分析、“星-地-人”协同的信号传递与优化控制3个关键科学问题,从“全域空间可解构”、“局部空间可解析”、“空间之间可传递”3个目标切入串联“空间表达”与“参数计算”前后两阶段,阐释了可靠表达、可信分析、可控计算的难点所在及可行求解路径。在此基础上,重点以农业生产空间的监测监管为需求导向,介绍了数字化底座的农业应用案例,通过展示其搭建过程与综合智能计算实施效果,说明底座之上承载并组合发挥时空数据要素的保障优势和基础性支撑作用,彰显了为复杂山地现代农业发展提供高品质时空信息服务的潜能。

关键词：高质量发展时空信息复杂地表系统地理时空数字化底座可靠表达可信分析可控计算数字农业应用

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