检索结果-南通市图书馆

Density-functional formula for strongly correlated systems

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2005年第5期15卷 395-401页

作者： WANG Huaiyu1*, han Rushan2.and CHEN Nanxian1(1. {2. of Physics, Tsinghua University, beijing 100084, China 2. {2. of Physics, Peking University, beijing 100871, China) department of Physics Tsinghua University Beijing 100084 China department of Physics Peking University Beijing 100871 China

Density functional method is applied for strongly correlated systems. Based on the assumption that the systems are composed of electrons in singly-occupied orbitals and those in doubly-occupied orbitals, a set of self-consistent equations are obtained by standard variation procedure. The equations consist of two parts. One part is to solve the wave functions of the electrons in singly-occupied orbitals and the other is to solve the wave functions of the electrons in doubly-occupied orbitals. The physical meanings of the terms appearing in the equations are discussed.

关键词： density-functional theory strongly correlated systems doubly-occupied orbital two-particle wave function self-consistent equations.

The^(40)Ar/^(39)Ar age record of formation and uplift of the blueschists and eclogites in the western Tianshan Mountains

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2000年第11期45卷 1047-1052页

作者： GAO Jun, ZhanG Lifei & LIU Shengwei1. Institute of geology, Chinese Academy of Geological Sciences,{2. 100037, China 2. {2. of geology, Peking University,{2. 100871, Chin Institute of geology Chinese Academy of Geological Sciences Beijing China department of geology Peking University Beijing China

The 40Ar/39Ar ages indicate that the eclogite facies rocks of the Hasiate slice in the western Tianshan Mountains were formed at the early stage of Devonian （401 Ma） and had been uplifted to the greenschist facies tectonic level in the middle stage of Devonian （381 Ma）. The formation and uplift of the blueschists of the Akesayi slice are constrained to the late stage of Devonian （370-364 Ma）. The different tectonic slices in the high-pressure metamorphic belt have experienced the different uplift history.

关键词： western Tianshan Mountains eclogite blueschist 40Ar/39Ar age.

Dehydration melting of solid amphibolite at 2.0 GPa: Effects of time and temperature

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2005年第8期48卷 1120-1133页

作者： ZHOU Wenge1, XIE Hongsen1, LIU Yonggang1, ZHENG Xiaogang1, ZHAO Zhidan2.& ZHOU Hui3 1. Laboratory of Material in the Earth’s Interior, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002. China 2. department of geology, China University of Geosciences,{2. 100083, China 3. department of geology, Peking University,{2. 100871, China 1. Laboratory of Material in the Earth’s Interior Institute of Geochemistry Chinese Academy of Sciences 550002 Guiyang China 2. department of geology China University of Geosciences 100083 Beijing China 3. department of geology Peking University 100871 Beijing China

Two sets of dehydration-melting with a natural solid amphibolite, collected from North Himalayan structure zone, Tibet, have been carried out in multi-anvil apparatus at 2.0 GPa and 800―1000℃, for 12.2.0 h. One is keeping the pressure at 2.0 GPa and the annealing time of 12.h, changing the temperature (800―1000℃). The other is keeping the pressure at 2.0 GPa and temperature at 850℃, varying the annealing time (12.2.0 h). The products are inspected with microscope and electron probe. The results indicate that at 2.0 GPa, annealing time of 12.h, garnets, melts and clinopyroxenes occur in amphibolite gradually with increasing temperature and the chemical compositions of melt vary from tonalite to granodiorite, and then to tonalite. However, at 2.0 GPa and 850℃, with the annealing time increasing, the garnets, melts and cli-nopyroxenes also occur in amphibolite gradually and the chemical compositions of melt vary from tonalite to granodiorite. In both cases, melts interconnect with each other when the contents of melt are over the 5 vol.%. the viscosities of the melt produced in amphibolite at temperature higher than 850℃ are on a level with 104 Pa·s. The interconnected melt with such a viscosity may segregate from the source rock and form the magma over reasonable geological time. Therefore, it is believed that at the lower part of the overthickened crust, the tonlitic and grano-dioritic magma may be generated through the dehydration melting of amphibolite.

关键词： solid amphibolite, high pressure, high temperature, time, partial melting.

A Potential Candidate For the Middle-Upper Cambrian Boundary Stratotype——An Introduction to the Paibi Section in Huayuan,Hunan

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 1990年第3期64卷 309-327,344-346+348页

作者： Dong Xiping department of geology, Peking University,{2. department of geology Peking University Beijing

The Middle-Upper Cambrian boundary is one of the current stratigraphical problems which remain openin the geological world, since there have been no universally acknowledged delimiting standard and *** on the instruction of Profs. Lu Yanhao and An Taixiang the author studied in details the Paibi Section,which is well exposed as a continuous sequence at an easily accessible locality. The Middle-Upper Cambrianboundary strata are composed of biocalcimicrosparite, indicating the sedimentary environment of anunderwater upheaval on the gentle slope along the frontal margin of the Yangtze carbonate platform. For the upper Middle and lower Upper Cambrian agnostid trilobite zones and conodont zones are erected,and a more accurate correlation between the trilobite and conodont sequences is established. Based on these,the Middle-Upper Cambrian boundary is drawn more reasonably and precisely than what was done before. Inshort, the section studied is superior to other known sections of Middle-Upper Cambrian. and it will probablybe an ideal candidate for the Middle-Upper Cambrian boundary stratotype.

关键词： In An Introduction to the Paibi Section in Huayuan,Hunan A Potential Candidate For the Middle-Upper Cambrian Boundary Stratotype

Metallogenic characteristics of epithermal gold deposits in China

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1999年第S2期44卷 136-138页

作者： FENG Jianzhong~1 and WANG Jingbin~2.1. department of geology, Peking University,{2. 100871, China 2.{2. Institute of geology For Mineral Resources,{2. 100012. China department of geology Peking University Beijing 100871 China beijing Institute of geology for Mineral Resources Beijing 100012 China

VOLCANIC-SUBVOLCANIC rocks are extensively distributed in China, in which a series of epithermal golddeposits related to volcanism have been discovered. 1 Metallogenic tectonic settings of epithermal gold deposits The epithermal gold deposits are mainly formed under the following tectonic settings: (i) ancient island arc collision, such as Xingxingxia island arc, Armantai island arc, Beishan island arc and Jueluotage island arc, etc. in periphery of Gunggar, Altai, Baishan, etc. in ancient Europe domain; (ii) extension area of continental margin of back arc, such as Fujian, Zhejiang, Jiangsu and Henlongjiang, *** circum-Pacific metallogenic domain; (iii) Mesozoic-Cenozoic island arc, such as the Tethys-Himalayametallogenic domain and Taiwan; (iV) intracontinental faulting depression or intraplate deep-seatedfaults, such as northern Hebei, Liaoning, Inner Mongolia at the north margin of the North China platformand periphery of Taicheng-Loujiang fault.

关键词： metallogenic characteristics gold deposits China.

Petrogenesis of Songshugou dunite body in the Qinling orogenic belt, Central China: Constraints from geochemistry and melt inclusions

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2005年第8期48卷 1146-1157页

作者： SU Li1,2. SONG Shuguang3 & ZHOU Dingwu1 1. Key Laboratory of Continental Dynamics of the Ministry of Education, department of geology, Northwestern University, Xi’an 710069, China 2. The Geological Lab Center, China University of Geosciences ({2.), beijing 100083, China 3. Key Laboratory of Orogenic Belts of the Ministry of Education, department of geology, Peking University, beijing 100871, China 1. Key Laboratory of Continental Dynamics of the Ministry of Education Department of Geology Northwestern University 710069 Xi’an China 2. The Geological Lab Center China University of Geosciences 100083 (Beijing)Beijing China 3. Key Laboratory of Orogenic Belts of the Ministry of Education Department of Geology Peking University 100871 Beijing China

The Songshugou dunite body, which occupies an area of about 2. km2. is the largest ultramafic massif in the eastern Qinling orogenic belt, Central China. The major compo-nent of this body is dunitic rocks including mylonitic dunite and coarse-grained dunite; they oc-cupy about 95 vol% of the total body. Petrography, mineral composition, major and trace ele-ments and primitive melt inclusions have been investigated in this paper; all revealed that this dunite body is the product of melt-rock interaction by porous percolation flow. In comparison with dunite sills or veins in harzburgite from the basal part of Oman ophiolite, this dunite body is characterized by lower contents of Al2.3, CaO and HREE but higher content of highly incom-patible elements and Zr and Hf. The LREE enriched patterns and primitive mantle normalized spidergrams of trace elements are also different from the Oman dunite. Combining with melt in-clusions observed in olivines, we conclude that this dunite body is the product of large- scale porous percolation flow of high-MgO melts within depleted mantle peridotites. The high-MgO magma, in essence, was most probably produced at the hot head of an upwelling mantle plume. The occurrence of the Songshugou dunite body is closely associated with the activity of mantle super-plume in Neo-Proterozoic era in the Yangtze Craton.

关键词： Songshugou dunite body, geochemistry, melt inclusion, mantle plume, Qinling orogenic belt.

Palaeogeographic Position of the South China Plate During the Early-Middle Devonian

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 1991年第1期65卷 19-26页

作者： Bai Zhiqiang Bai Shunliang department of geology, Peking University,{2. department of geology Peking University Beijing

In Guangxi, the Lower-Middle Devonian boundary beds yield abundant corals, brachiopods,stromatoporoids and conodonts. The former three were common in tropical and subtropical zones, while thelast occurred only round the equator. This reveals that the South China Plate in the Early-Middle Devonianwas at or near the equator, which was also supported by palaeomagnetic study giving the palaeolatitude of theGuangxi Region at the time to be 0°36′N.

关键词： Palaeogeographic Position of the South China Plate During the Early-Middle Devonian

Temporal and Spatial Optimization for 5G Base Station Groups in Distribution Networks

在线全文

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1159-1169页

作者： Silu Zhang Nian Liu Jianpei han department of Electrical and Electronic Engineering North China Electric Power UniversityBeijingChina

With the large-scale connection of 5G base stations(BSs)to the distribution networks(DNs),5G BSs are utilized as flexible loads to participate in the peak load regulation,where the BSs can be divided into base station groups(BSGs)to real-ize inter-district energy transfer.A Stackelberg game-based opti-mization framework is proposed,where the distribution net-work operator(DNO)works as a leader with dynamic pricing for multi-BSGs;while BSGs serve as followers with the ability of demand response to adjust their charging and discharging strategies in temporal dimension and load migration strategy in spatial ***,the presence and uniqueness of the Stackelberg equilibrium(SE)are ***,differ-ential evolution is adopted to reach the SE and the optimization problem in multi-BSGs is decomposed to solve the time-space ***,through simulation of a practical system,the results show that the DNO operation profit is increased via cut-ting down the peak load and the operation costs for multi-BSGs are reduced,which reaches a win-win effect.

关键词： 5G base station dynamic pricing demand response energy storage load migration Stackelberg game optimization

Advanced Sensors Towards Ubiquitous Power Internet of Things

在线全文

学校读者我要写书评

暂无评论

CSEE Journal of Power and Energy Systems 2024年第3期10卷 871-890页

作者： Jinliang He Zhifei han Jun Hu department of Electrical Engineering Tsinghua UniversityBeijing 100084China IEEE CSEE

The ubiquitous power Internet of Things(UPIoT)uses modern information technology and advanced communication technologies to realize interconnection and human-computer interaction in all aspects of the power *** has the characteristics of comprehensive state perception and efficient information processing,and has broad application prospects for transformation of the energy *** fundamental facility of the UPIoT is the sensor-based information *** using advanced sensors,Wireless Sensor Networks(WSNs),and advanced data processing technologies,Internet of Things can be realized in the power *** this paper,a framework of WSNs based on advanced sensors towards UPIoT is *** addition,the most advanced sensors for UPIoT purposes are reviewed,along with an explanation of how the sensor data obtained in UPIoT is utilized in various scenarios.

关键词： Advanced sensors ubiquitous power Internet of Things wireless sensor networks