检索结果-南通市图书馆

Finite Size Effect on the in-Medium Chiral Condensate at Finite Density

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2014年第4期31卷 18-21页

作者： XIA Cheng-Jun peng guang-xiong HOU Jia-Xun School of Physics University of Chinese Academy of Sciences Beijing 100049 Theoretical Physics Center for Science Facilities Institute of High Energy Physics Beijing 100049

The in-medium quark condensate is studied with an equivalent quark mass approach that has the advantage of no need for extra assumptions on the current mass derivatives of model parameters with respect to the quark current mass. It is found that the ratio of the quark condensate in a medium to that in a vacuum depends not only on density but also on the finite size. With decreasing volume, it decreases to a minimum, and then saturates at a radius of about 1 fro. The condensate approaches to its bulk value when the volume becomes infinitely large, and it decreases finearly with increasing density if the density is extremely low.

关键词： QUARKS QUANTUM chromodynamics HAMILTONIAN systems THERMODYNAMICS BARYONS

A Forest Fire Risk Assessment Using ASTER Images in Peninsular Malaysia

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of China University of Mining and Technology 2007年第2期17卷 232-237页

作者： peng guang-xiong LI Jing CHEN Yun-hao NORIZAN Abdul-patah College of Resources Science ＆ Technology Beijing Normal University State Key Laboratory of Earth Surface Processes and Resource Ecology （Beijing Normal University） Beijing 100875 China Hunan Provincial Meteorological Observatory Changsha Hunan 410007 China Malaysian Centre for Remote Sensing Kuala Lumpur 50480 Malaysia

Based on the physical concept of heat energy of pre-ignition,a new fire susceptibility index (FSI) is used to estimate forest fire risk. This physical basis allows calculation of ignition probabilities and comparisons of fire risk across eco-regions. The computation of the index requires inputs of fuel temperature and fuel moisture content (FMC),both of which can be estimated using remote sensing data. While ASTER data for land surface temperatures (LST) was used as proxys for fuel temperatures,fuel moisture content is estimated by regression technique utilizing the ratio NDVI/LST of ASTER data. FSIs are computed in peninsular Malaysia for nine days before the fires of 2004 and 2005 and validated with fire occurrence data. Results show that the FSI increases as the day approaches the fire day. This trend can be observed clearly about four days before the day of fire. It suggests that FSI can be a good estimator of fire risk. The physical basis provides a more meaningful FSI,allows calculation of ignition probabilities and facilitates the development of a future class of fire risk models. FSI can be used to compare fire risk across different eco-regions and time periods. FSI retains the flexibility to be localized to a vegetation type or eco-regions for improved performance.

关键词： fire risk fire susceptibility index land surface temperature fuel moisture content

Λ^(*) Resonance Model Calculation of K^(-)p→ηΛ Reaction Near Threshold

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 1999年第5期16卷 347-349页

作者： JIANG Huan-qing peng guang-xiong YU Tao Institute of High Energy Physics Chinese Academy of SciencesBeijing 100039

AΛ^(*) resonance model for the η-Λ interaction near threshold is *** assuming the Λ^(*)(1670)excitation dominates in the K^(-)p→ηΛ reaction near threshold,the corresponding η production cross section and the s-wave η-Λ scattering length are *** obtained production cross section is consistent with the available experimental data,which indicates that the Λ^(*)(1670)excitation is dominant in the production reaction near *** η-Λ interaction is found to be attractive.

关键词： excitation attractive interaction

Pegmatite remote sensing extraction and metallogenic prediction in Azubai area,Xinjiang

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 2011年第S3期21卷 543-548页

作者： peng guang-xiong1, 2, YE Zhen-chao1, 2, GAO guang-ming1, 2, FENG De-shan1, xiong Yun1 1. School of Geosciences and Info-Physics, Central South University, Changsha 410083, China 2. Key Laboratory of Metallogenic Prediction of Nonferrous Metals, Ministry of Education, Changsha 410083, China [a] School of Geosciences and Info-Physics Central South University Changsha 410083 China [b] Key Laboratory of Metallogenic Prediction of Nonferrous Metals Ministry of Education Changsha 410083 China

Remote sensing technique plays an important role in geological prospecting in Altay because of the remote location and steep terrain with mountains. Pegmatite has important implications for metallogenic prospecting as most of rare metals occurs in it. Pegmatite information from optical and radar images was extracted, and the spatial distribution and scale of pegmatite were generalized in Azubai, Altay. Three mining targets, that is, Halon-Azubai, Kuermutu-Tuyibaguo and Zhuolute-Akuoyige, were delineated based on the analysis of pegmatite information, structure interpretation and other geological data.

关键词： pegmatite remote sensing information extraction metallogenic prediction

Properties of color-flavor locked strange quark matter in an external strong magnetic field

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2015年第4期26卷 83-89页

作者：崔帅帅彭光雄陆振烟彭程徐建峰 School of Physics University of Chinese Academy of Sciences Theoretical Physics Center for Science Facilities Chinese Academy of Sciences

The properties of color-flavor locked strange quark matter in an external strong magnetic field are investigated in a quark model with density-dependent quark *** are determined by stability *** is found that the minimum energy per baryon of the color-flavor locked(MCFL)matter decreases with increasing magnetic-field strength in a certain range,which makes MCFL matter more stable than other phases within a proper magnitude of the external magnetic ***,if the energy of the field itself is added,the total energy per baryon will increase.

关键词：奇异夸克物质强磁场性质锁定最小能量稳定性参数夸克模型夸克质量

在线全文

学校读者我要写书评

暂无评论

河南嵩县安沟钼多金属矿床的地质特征与成因

中国有色金属学报 2012年第3期22卷 819-826页

作者：叶震超高光明彭光雄中南大学有色金属成矿预测教育部重点实验室长沙410083 中南大学地球科学与信息物理学院长沙410083

安沟钼矿产于东秦岭钼成矿带燕山期花岗岩与花岗斑岩发育处。采用系统的地质勘测手段与微量元素特征分析方法对矿床的地质特征和矿床成因进行研究。结果表明:区内花岗类岩体w(Rb)/w(Sr)值较低,说明该岩浆来源较深;地层与岩体中Mo元素含... 详细信息

安沟钼矿产于东秦岭钼成矿带燕山期花岗岩与花岗斑岩发育处。采用系统的地质勘测手段与微量元素特征分析方法对矿床的地质特征和矿床成因进行研究。结果表明:区内花岗类岩体w(Rb)/w(Sr)值较低,说明该岩浆来源较深;地层与岩体中Mo元素含量远高于平均值,在矿体周边岩体的Mo含量极低,说明岩浆与热液之间存在强烈的萃取作用;Pb与Au和Ag在成因上呈正相关,钼矿与其他元素成矿关系不明显;矿床为斑岩-爆破角砾岩型,成矿过程可归纳为中生代拆离断层体系形成、岩浆侵位与矿质元素萃取、超浅成侵位与爆破作用及热液成矿4个阶段。

关键词：安沟爆破角砾岩微量元素地质特征矿床成因

Multifunctional Nacre‑Like Nanocomposite Papers for Electromagnetic Interference Shielding via Heterocyclic Aramid/MXene Template‑Assisted In‑Situ Polypyrrole Assembly

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2025年第3期17卷 37-54页

作者： Jinhua xiong Xu Zhao Zonglin Liu He Chen Qian Yan Huanxin Lian Yunxiang Chen Qingyu peng Xiaodong He National Key Laboratory of Science and Technology On Advanced Composites in Special Environments Center for Composite Materials and StructuresHarbin Institute of TechnologyHarbin 150080People’s Republic of China

Robust, ultra-flexible, and multifunctional MXene-basedelectromagnetic interference (EMI) shielding nanocomposite filmsexhibit enormous potential for applications in artificial intelligence,wireless telecommunication, and portable/wearable electronic *** this work, a nacre-inspired multifunctional heterocyclic aramid(HA)/MXene@polypyrrole (PPy) (HMP) nanocomposite paper withlarge-scale, high strength, super toughness, and excellent tolerance tocomplex conditions is fabricated through the strategy of HA/MXenehydrogel template-assisted in-situ assembly of PPy. Benefiting from the"brick-and-mortar" layered structure and the strong hydrogen-bondinginteractions among MXene, HA, and PPy, the paper exhibits remarkable mechanical performances, including high tensile strength (309.7 MPa),outstanding toughness (57.6 MJ m−3), exceptional foldability, and structural stability against ultrasonication. By using the template effect ofHA/MXene to guide the assembly of conductive polymers, the synthesized paper obtains excellent electronic conductivity. More importantly,the highly continuous conductive path enables the nanocomposite paper to achieve a splendid EMI shielding effectiveness (EMI SE) of 54.1 dBat an ultra-thin thickness (25.4 μm) and a high specific EMI SE of 17,204.7 dB cm2g−1. In addition, the papers also have excellent applicationsin electromagnetic protection, electro-/photothermal de-icing, thermal therapy, and fire safety. These findings broaden the ideas for developinghigh-performance and multifunctional MXene-based films with enormous application potential in EMI shielding and thermal management.

关键词： MXene Remarkable mechanical properties Heterocyclic aramid Electromagnetic interference shielding Polypyrrole Multifunctionality

基于烟羽掩膜的森林火点MODIS探测方法研究

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

红外与毫米波学报 2008年第3期27卷 185-189页

作者：彭光雄沈蔚胡德勇李京陈云浩中国科学院遥感应用研究所北京100101 上海水产大学上海200090 首都师范大学资源环境与旅游学院北京100037 北京师范大学资源学院北京100875

针对MODIS的林火探测算法第四版区域适应性差的不足,利用基于热带雨林特性的潜在火点判定阈值和基于烟羽掩膜的自适应窗口调节技术,对第四版算法进行了改进.烟羽掩膜有利于辅助火点探测,而调整阈值则能改善火点探测的敏感性.根据热带雨... 详细信息

针对MODIS的林火探测算法第四版区域适应性差的不足,利用基于热带雨林特性的潜在火点判定阈值和基于烟羽掩膜的自适应窗口调节技术,对第四版算法进行了改进.烟羽掩膜有利于辅助火点探测,而调整阈值则能改善火点探测的敏感性.根据热带雨林地区森林火灾的特点,潜在火点判定阈值在无烟羽区设为306K,在烟羽掩膜区设为295K.烟羽掩膜可以有效圈定背景像元的范围,增加自适应窗口空间统计分析的约束条件,减少由于降低烟羽掩膜区潜在火点判定阈值而引起的噪声.应用实际火点数据对两种算法进行了比较验证分析.结果表明改进算法后提高了对低温小火点和大扫描角火点探测的敏感性,增强了热带雨林地区的火点探测能力和探测精度.

关键词：森林火灾火点探测烟羽掩膜中分辨率成像光谱仪

质量密度相关模型研究CFL奇异夸克物质性质(英文)

在线全文

学校读者我要写书评

暂无评论

高能物理与核物理 2007年第3期31卷 269-273页

作者：陈曰德彭光雄温新建中国科学院高能物理研究所北京100049 中国科学院研究生院北京100049

在质量-密度相关模型下研究了CFL奇异夸克物质,并将结果与传统的袋模型结果进行比较．两个模型均表明,在合理的参数范围内,CFL相比正常核物质更稳定．然而,低密度时声速的行为完全相反,这使得CFL夸克星的最大质量在质量-密度相关模型下... 详细信息

在质量-密度相关模型下研究了CFL奇异夸克物质,并将结果与传统的袋模型结果进行比较．两个模型均表明,在合理的参数范围内,CFL相比正常核物质更稳定．然而,低密度时声速的行为完全相反,这使得CFL夸克星的最大质量在质量-密度相关模型下比袋模型大．

关键词：色超导奇异夸克物质夸克星