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First principles study on electronic structure and optical properties of quaternary arsenide oxides YZnAsO and LaZnAsO 被引量:1
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作者 施毅敏 叶绍龙 《Journal of Central South University》 SCIE EI CAS 2011年第4期998-1003,共6页
The electronic structure and optical properties of the tetragonal phase quaternary arsenide oxides YZnAsO and LaZnAsO were studied using density-functional theory(DFT) within generalized gradient approximation(GGA).Th... The electronic structure and optical properties of the tetragonal phase quaternary arsenide oxides YZnAsO and LaZnAsO were studied using density-functional theory(DFT) within generalized gradient approximation(GGA).The band structure along the higher symmetry axes in the Brillouin zone,the density of states(DOS) and the partial density of states(PDOS) were presented.The calculated energy band structures show that both YZnAsO and LaZnAsO are indirect gap semiconductors with band gap of 1.173 1 eV and 1.166 5 eV,respectively.The DOS and PDOS show the hybridization of Y-O/La-O atom orbits and Zn-As atom orbits.The dielectric function,reflectivity,absorption coefficient,refractive index,electron energy-loss function and optical conductivity were presented in an energy range from 0 to 25 eV for discussing the optical properties of YZnAsO and LaZnAsO. 展开更多
关键词 YZnAsO/LaZnAsO density-functional theory generalized gradient approximation electronic structure optical properties
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The National Monument in Indonesia: The Visual Art in Sacred Space
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作者 Yuke Ardhiati 《Journal of Literature and Art Studies》 2012年第9期872-880,共9页
The paper is a part of the dissertation to reveal the psyche of the Ruler as the authorized man created the "space" in the Monument National in Indonesia, through investigation related metaphysically data as a proce... The paper is a part of the dissertation to reveal the psyche of the Ruler as the authorized man created the "space" in the Monument National in Indonesia, through investigation related metaphysically data as a process to having qualities becoming to "Indonesia". By using the Grounded Theory research method, which refers to Glaser and Strauss, phenomenological observations and Hermeneutic-lnterpretive method of Ricouer, the process of deriving quality form an architectural presence is revealed. By connecting the Spatial Archetype Theory of LobeU, the paper reveals the "inflated ego of the Ruler as Leader" was manifested by symbol rays of Radiant Axes civilization through Soekarno's unconsciousness thought of space. The presence of architecture the National Monument serves not merely as a city landmark, but more than that, it roles as the center of orientation and development for a Jakarta Master plan conceived 50 years ago and still maintained to this day as the basic of the Jakarta City Planning 2030 In effect, this means that the National Monument plays the role as the axis of Indonesia's modem civilization. 展开更多
关键词 Khora Radiant Axes civilization Soekarno's inflated ego Tugu National the modem civilization axis
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Influence of moisture content on shearing strength of unsaturated undisturbed quaternary system middle pleistocene 被引量:6
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作者 钟祖良 刘元雪 +2 位作者 刘新荣 李小勇 王睢 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第7期2776-2782,共7页
The unsaturated undisturbed quaternary system middle pleistocene loess,a typical unsaturated soil,often occurs in the implementation of western development strategy.To obtain the shearing strength characteristics of t... The unsaturated undisturbed quaternary system middle pleistocene loess,a typical unsaturated soil,often occurs in the implementation of western development strategy.To obtain the shearing strength characteristics of this unsaturated undisturbed loess,based on the analysis of mineral composition,the triaxial shear test of undisturbed quaternary system middle pleistocene loess under different moisture contents is conducted with the specialized triaxial instrument for unsaturated soil.The test results show that the mainly mineral composition of undisturbed quaternary system middle pleistocene loess is quartz and albite.Under the same confining pressure,the matric suction increases with the decrease of moisture content.The smaller the moisture content,the larger the matric suction;the higher the moisture content,the lower the matric suction.Under the same moisture content,the matric suction increases with the confining pressure and reaches a maximum when the confining pressure is 100 kPa,and then decreases with the increase of confining pressure.This phenomenon is closely related to the grain contact tightness of soil mass under high confining pressure.According to the triaxial test of loess,the sample of loess experiences 4 stages from loading to failure:1) compaction stage;2) compression stage;3) microcrack developing stage;4) shear failure stage.The test sample is of brittle failure(weak softening)under low moisture content and confining pressure.With the decrease of matric suction and the increase of consolidated confining pressure,the stress-strain curve changes from softening type to ideal plastic type.In the shearing strength parameters of unsaturated undisturbed loess,the influence of moisture content on internal friction angle is small,but that on cohesive force is obvious.Therefore,the shearing strength of unsaturated undisturbed loess is higher than that of saturated undisturbed loess and varies with the moisture content. 展开更多
关键词 unsaturated undisturbed loess matric suction test shearing strength
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China's Sloping Land Conversion Program at the Beginning of 21st Century and Its Habitat Suitability in Typical Region of Loess Plateau 被引量:7
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作者 董金玮 刘纪远 史文娇 《Journal of Resources and Ecology》 CSCD 2010年第1期36-44,共9页
自1999年我国开始试行以"退耕还林"工程为主的生态退耕以来,到目前已历时十年。特别是进入21世纪,工程实施强度较大,因此从国家尺度上进行宏观生态退耕格局的分析对于评估生态退耕政策和确定未来政策导向具有重要意义。本研究... 自1999年我国开始试行以"退耕还林"工程为主的生态退耕以来,到目前已历时十年。特别是进入21世纪,工程实施强度较大,因此从国家尺度上进行宏观生态退耕格局的分析对于评估生态退耕政策和确定未来政策导向具有重要意义。本研究以TM遥感监测的土地利用变化数据库为基础分析2000-2005年生态退耕的时空格局。在此基础上,以黄土高原典型地区陕西中北部为研究区,采用生态位适宜度评价模型探讨了生态退耕工程实施的合理性。研究结果表明:(1)2000-2005年间,生态退耕主要集中在中国中部地区,尤其是在黄河和长江的中上游地区,生态退耕面积与建设占用面积基本持平。在各生态类型区中,黄土高原土壤侵蚀区生态退耕面积最大,达到了1162.50km^2,主要用于还林;(2)整体看来,研究区内生态退耕的空间格局是合理的,即适宜性越差的耕地退耕比例越大。从退耕区域的适宜性水平来看,有77.35%的地区属于勉强适宜区,其中退为林地的面积为603.32km^2,退为草地的面积为528.94km^2。整个研究区内前者大于后者。然而,退耕地中仍有19.38%属于中度适宜区,原因可能来自于退耕指标分配等管理因素,另外,当地农民外出务工从而将中等适宜度的耕地退耕。结果表明,当前仍有大面积不适宜和勉强适宜的耕地存在,在未来工程实施过程区应该首先考虑该类地区。 展开更多
关键词 SLCP habitat suitability China the beginning of 21st century the Loess Plateau
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明清宫廷交椅考述 被引量:5
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作者 李建华 《沈阳故宫博物院院刊》 2013年第1期45-55,共11页
交椅是中国家具体系中最为独特的品种之一,其前身胡床的输入,一改三代以来中国传统的茵席踞坐而进入了垂足而坐的高坐具时代,这一在一定程度上改变了中国古人传统的生活方式和礼俗观念。交椅发端于晚唐,兴盛于两宋,精到于朱明直至清朝... 交椅是中国家具体系中最为独特的品种之一,其前身胡床的输入,一改三代以来中国传统的茵席踞坐而进入了垂足而坐的高坐具时代,这一在一定程度上改变了中国古人传统的生活方式和礼俗观念。交椅发端于晚唐,兴盛于两宋,精到于朱明直至清朝中道渐落,千年之中一直作为中国主流家具之一存在并延续,成为中国家具发展史上少有的聚用材、技术、工艺乃至思想文化于一器的集成之作。一、明清宫廷交椅的类型交椅自游牧民族的胡床演化而来,《事务纪原》引《风俗通》载:'汉灵帝好胡服。 展开更多
关键词 思想 工艺 宫廷 中国 胡床 家具 交椅
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兩宋時期對《三國志》的考據 被引量:1
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作者 楊小平 《宋代文化研究》 2015年第1期262-276,共15页
考據是《三國志》研究中最容易被人關注的,涉及《三國志》考據研究的論著,宋代有晁公武《郡齋讀書志》、高承《事物紀原》、陸游《老學庵筆記》、周密《齊東野語》、宋祁《宋景文公筆記》、沈括《夢溪筆談》、程大昌《演繁露》、朱翌《... 考據是《三國志》研究中最容易被人關注的,涉及《三國志》考據研究的論著,宋代有晁公武《郡齋讀書志》、高承《事物紀原》、陸游《老學庵筆記》、周密《齊東野語》、宋祁《宋景文公筆記》、沈括《夢溪筆談》、程大昌《演繁露》、朱翌《猗覺察雜記》、孫奕《履齋示兒編》、張涣《雲谷雜記》、沈作喆《寓簡》、袁文《甕牖閑評》、戴埴《鼠璞》、王觀國《學林》、黄朝英《靖康緗素雜記》、陳善《捫虱新話》、吳曾《能改齋漫錄》、王楙《野客叢書》、高似孫《史略》 展开更多
关键词 紀原 公筆 國志 陸游 考據 野客 雜記 雲谷
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两汉铁钱考 被引量:1
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作者 傅举有 《湖南考古辑刊》 1984年第1期183-190,共8页
我国最早的铁铸币,过去都认为产生于东汉初年。据宋代高承《事物纪原》说:'以铁为钱,始于公孙述之据蜀也'。公孙述曾于东汉建武六年(公元30年)'废铜钱,置铁官钱',即'置铁官以铸钱'~①。唐代社佑的《通典》也认... 我国最早的铁铸币,过去都认为产生于东汉初年。据宋代高承《事物纪原》说:'以铁为钱,始于公孙述之据蜀也'。公孙述曾于东汉建武六年(公元30年)'废铜钱,置铁官钱',即'置铁官以铸钱'~①。唐代社佑的《通典》也认为这是最早的铁钱。从唐宋以来,公孙述始作铁钱就几乎成为定论。解放后,研究货币史的同志,又沿袭旧说,认定公孙述的铁钱,'是为中国有铁钱之始'~②。 展开更多
关键词 社佑 研究 通典 铁官 定论 铁钱
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Restudy of the storage and migration model of the Quaternary groundwater in Beijing Plain area 被引量:9
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作者 LIU YuanZhang WU Qiang +3 位作者 LIN Pei LIU JiuRong XING LiTing GAO ZhiHui 《Science China Earth Sciences》 SCIE EI CAS 2012年第7期1147-1158,共12页
Through a wide-spread groundwater sampling mainly at nested monitoring wells in the Beijing Plain area, combined with data collection, the study analyzes water level, hydrochemistry, temperature, tritium, deuterium, 1... Through a wide-spread groundwater sampling mainly at nested monitoring wells in the Beijing Plain area, combined with data collection, the study analyzes water level, hydrochemistry, temperature, tritium, deuterium, 180, 14C and other aspects, and in- dicates that there exits an obvious stratification phenomenon of the groundwater in the alluvial plain area down in the middle part of alluvial-pluvial fans, and the hydraulic connection between layers is very weak. The analysis of the tritium concentra- tion suggests that the average influence depth of the modem precipitation is approximately 120 m. Based on the analysis of the 22 paleowater samples through the D-~80 method and 14C isotopic dating, the deep groundwater circulation in the fine sedi- ments area of Beijing Plain down in the fringe part of alluvial-pluvial fans is relatively slow. On average the paleowater point occurs approximately below the 180 m at these points. The main reasons for the formation of stratification and paleowater points are the water-blocking effect of the clay type strata and the compaction effect during the sedimentary process, especially the differential compaction, which could form closed or relatively closed stagnant aquifers. Groundwater in this kind of stagnant aquifers to some degree belongs to non-renewable resource, and should be reconsidered and re-arranged in the water resources management strategy. 展开更多
关键词 Beijing Plain area stratified monitoring wells ISOTOPE stagnant aquifers non-renewable resource
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Causes and consequences of the Cambrian explosion 被引量:21
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作者 ZHANG XingLiang SHU DeGan 《Science China Earth Sciences》 SCIE EI CAS 2014年第5期930-942,共13页
The Cambrian explosion has long been a basic research frontier that concerns many scientific fields. Here we discuss the cause-effect links of the Cambrian explosion on the basis of first appearances of animal phyla i... The Cambrian explosion has long been a basic research frontier that concerns many scientific fields. Here we discuss the cause-effect links of the Cambrian explosion on the basis of first appearances of animal phyla in the fossil record, divergence time, environmental changes, Gene Regulatory Networks, and ecological feedbacks. The first appearances of phyla in the fos- sil record are obviously diachronous but relatively abrupt, concentrated in the first three stages of the Cambrian period (541- 514 Ma). The actual divergence time may be deep or shallow. Since the gene regulatory networks (GRNs) that control the de- velopment of metazoans were in place before the divergence, the establishment of GRNs is necessary but insufficient for the Cambrian explosion. Thus the Cambrian explosion required environmental triggers. Nutrient availability, oxygenation, and change of seawater composition were potential environmental triggers. The nutrient input, e.g., the phosphorus enrichment in the environment, would cause excess primary production, but it is not directly linked with diversity or disparity. Further in- crease of oxygen level and change of seawater composition during the Ediacaran-Cambrian transition were probably crucial environmental factors that caused the Cambrian explosion, but more detailed geochemical data are required. Many researchers prefer that the Cambrian explosion is an ecological phenomenon, that is, the unprecedented ecological success of ruetazoans during the Early Cambrian, but ecological effects need diverse and abundant animals. Therefore, the establishment of the eco- logical complexity among animals, and between animals and environments, is a consequence rather than a cause of the Cam- brian explosion. It is no doubt that positive ecological feedbacks could facilitate the increase of biodiversity. In a word, the Cambrian explosion happened when environmental changes crossed critical thresholds, led to the initial formation of the meta- zoan-doruinated ecosystem through a series of knock-on ecological processes, i.e., "ecological snowball" effects. 展开更多
关键词 Cambrian explosion dGRNs GONDWANA environmental changes ecological snowball
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Species diversification and phylogeographical patterns of birds in response to the uplift of the Qinghai-Tibet Plateau and Quaternary glaciations 被引量:14
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作者 Fumin LEI Yanhua QU Gang SONG 《Current Zoology》 SCIE CAS CSCD 2014年第2期149-161,共13页
The Qinghai-Tibet Plateau (QTP) is well known for being of great importance in the evolution of montane species due to its unique geological history and landform configuration, climate complexity, and diversified ha... The Qinghai-Tibet Plateau (QTP) is well known for being of great importance in the evolution of montane species due to its unique geological history and landform configuration, climate complexity, and diversified habitats. The effect of environmental changes since the Quaternary on species diversification, population genetic structure, and demography under environmental change can be studied using phylogenetic and phylogeographieal approaches. Birds are the most well-studied group of all terrestrial vertebrates with regard to their response to climatic changes over time. Herein, we briefly review the species diversification of birds in response to the uplift of the QTP, focusing on summarizing the different phylogeographical patterns of birds on the Plateau, its southeastern margin, and the Eastern Himalayas and the reasons underlying these patterns. Speciation was found to be closely related to the uplift of the QTP, with different patterns of intraspecific processes: (1) no divergence within a single refuge was identified in a restricted semi-continuous area of the eastern margin of the Plateau; (2) two divergent lineages with separated refugia were located at the south-eastern and north-eastern margins of the plateau; and (3) multiple divergent lineages within subregions were found in the Eastern Himalayas. Glacial movements and induced climate change are considered to be key factors in shaping these different patterns. The species distributed mainly in the heavily ice-covered platform regions of the Plateau experienced population expansion following the retreat of the extensive glaciations, whereas the species distributed on the ice-free edges of the plateau maintained their population size at a stable level. Demographic stresses on the edge species might have been mitigated by the milder climate in comparison to their platform-distributed counterparts. Various behavioral and ecological characteristics, including dispersal capacity, habitat preference, and elevation specificity, along with evolutionary history might have helped to shape these different phylogeographical patterns [Current Zoology 60 (2): 149-161, 2014]. 展开更多
关键词 Qinghai-Tibet Plateau Comparative phylogeography BIRD Pleistocene glaciations
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Late Quaternary glacial chronology on the eastern slope of Gongga Mountain,eastern Tibetan Plateau,China 被引量:11
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作者 WANG Jie PAN BaoTian +3 位作者 ZHANG GuoLiang CUI Hang CAO Bo GENG HaoPeng 《Science China Earth Sciences》 SCIE EI CAS 2013年第3期354-365,共12页
The Gongga Mountain is the largest area of modern glaciation in the Hengduan Mountains and,with a summit elevation of 7556 m,is the highest mountain on the eastern margin of the Tibetan Plateau.During the Quaternary g... The Gongga Mountain is the largest area of modern glaciation in the Hengduan Mountains and,with a summit elevation of 7556 m,is the highest mountain on the eastern margin of the Tibetan Plateau.During the Quaternary glacial-interglacial cycles the Gongga Mountain was extensively and repeatedly glaciated,and glacial landforms and outwash deposits from multiple glaciations are well-preserved in valleys,in basins,and on piedmonts.To constrain the glacial chronology of the eastern slope of Gongga Mountain,sample sites were selected based on the distribution and weathering of glacial tills,relationships among glacial deposits,and soil development on moraines.Dating of the tills and glaciofluvial deposits was undertaken with electron spin resonance(ESR) and optically stimulated luminescence(OSL).The ages of the glacial deposits can be divided into four clusters:2.2±0.5,11.9±0.6,35.9±2.7-58.0±6.3 and 119.2±15.9-194.2±32.8 ka.Five glacial advances in this region have been identified,which are equivalent in age to the Little Ice Age(LIA),Neoglaciation,marine oxygen isotope stage(MIS) 2,mid-MIS3,and MIS6.The largest local last glacial maximum(LGML) occurred on Gongga Mountain during mid-MIS3,characterized by a cold-humid climate,rather than the global Last Glacial Maximum(LGMG) of MIS2.The Gongga,Nanmenguangou(NMGG) and Yajiageng Glaciations occurred during the late part of the last glacial cycle,the middle of the last glacial cycle and the penultimate glacial cycle,respectively.On the basis of geomorphological,sedimentological,and compositional characteristics,landforms of the Moxi Platform and terraces can be grouped by facies and geochronology.In combination with the dating results,this analysis indicates the basal part of the Moxi Platform between Xinxin and the Moxi Hotel is correlative with the till of the Nanguanmen Glaciation(mid-MIS3).This basal unit has occasional lenses of glaciofluvial sandy gravel and lacustrine sediments.The remainder of the Moxi Platform and the terraces beside the platform are glaciofluvial deposits occasionally mixed with debris flow deposits and range in age from MIS3 to Holocene. 展开更多
关键词 ESR dating glacial chronology Gongga Mountain Moxi Platform OSL dating
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Primary study on pattern of general circulation of atmosphere before uplift of the Tibetan Plateau in eastern Asia 被引量:9
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作者 江新胜 潘忠习 付清平 《Science China Earth Sciences》 SCIE EI CAS 2001年第8期680-688,共10页
The Tibetan Plateau is a key factor for the pattern of the general circulation of the atmosphere (GCA) in eastern Asia. The pattern of the GCA after the uplift of the plateau is well known, while the pattern of the GC... The Tibetan Plateau is a key factor for the pattern of the general circulation of the atmosphere (GCA) in eastern Asia. The pattern of the GCA after the uplift of the plateau is well known, while the pattern of the GCA before the uplift of the plateau is lack of direct evidences. Based on the knowability of desert, a section recording wind directions across the Cretaceous northern hemisphere mid-low latitude desert belt is measured and the pattern of the GCA in the Cretaceous is revealed. The result shows that the eastern Asia was really controlled by the planetary circulation before the uplift of the plateau, i.e. westerlies in the north and northeast trades in the south. The convert belt between westerlies and trades had drifted northwards and southwards. The possibility of existence of paleo-monsoon is also dealt with and a possibly imposed paleo-monsoon is suggested. 展开更多
关键词 before the uplift of the Tibetan Plateau the Cretaceous desert belt the pattern of the general circulation of the atmosphere in eastern Asia
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New ommatids from the Late Jurassic of western Liaoning, China (Coleoptera: Archostemata) 被引量:8
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作者 JING-JINGTAN DONGREN MINGLIU 《Insect Science》 SCIE CAS CSCD 2005年第3期207-216,共10页
A new genus Amblomma gen. nov. of fossil beetles is erected and can be assignedto the family Ommatidae because its two procoxal cavities are contiguous and the articulations of the abdominal ventrites are abutting. Th... A new genus Amblomma gen. nov. of fossil beetles is erected and can be assignedto the family Ommatidae because its two procoxal cavities are contiguous and the articulations of the abdominal ventrites are abutting. The new genus is similar to Zygadenia Handlirsch, 1906 (=Notocupes Ponomarenko, 1964), Tetraphalerus Waterhouse, 1901,Rhobdocupes Ponomarenko, 1966 and Sinocupes Lin, 1976, but can be distinguished from other genera according to the following characters: the second segment of antennae is shorterthan the third one in length; the posterior tarsi with the basal segment is obviously shorter than the three following taken together in length; the antennae reach the posterior ridge of prothroax in length, and the sides of the prothroax with serrulate margin. Four new species of the new genus are described and figured: Amblomma psilata gen. et sp. nov., Amblomma rudis gen. et sp. nov., Amblomma epicharis gen. et sp. nov., and Amblomma stabilis gen. etsp. nov. A key to species within this new genus is provided. All the specimens are collected from the Late Jurassic Yixian Formation of western Liaoning and are now housed in the College of Life Science, Capital Normal University, Beijing, China. 展开更多
关键词 ommatidae cupedidae new genus new species JURASSIC yixian formation
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Quaternary glacial geomorphology and glaciations of Kongur Mountain,eastern Pamir,China 被引量:17
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作者 WANG Jie ZHOU ShangZhe +2 位作者 ZHAO JingDong ZHENG JingXiong GUO XiangZhong 《Science China Earth Sciences》 SCIE EI CAS 2011年第4期591-602,共12页
Kongur Mountain is the largest center of modern glaciation on the Pamir Plateau.During the glacial-interglacial cycles of the Quaternary,Kongur Mountain was extensively and repeatedly glaciated,and the glacial landfor... Kongur Mountain is the largest center of modern glaciation on the Pamir Plateau.During the glacial-interglacial cycles of the Quaternary,Kongur Mountain was extensively and repeatedly glaciated,and the glacial landforms from multiple glaciations are well-preserved in valleys,in basins,and on the piedmonts.Dating samples have been collected according to the distribution and weathering of the glacial tills,the relationship among the glacial deposits,and the loess or soil developed on the moraines. Electron spin resonance(ESR) dating of the samples was done using the germanium(Ge) centers in the glacial quartz grains,which are sensitive to both sunlight and grinding.The ages of the glacial deposits can be divided into four clusters,i.e.,13.1±0.8-27.0±2.2,36.4±3.3-48.7±5.7,65.6±6.8-86.6±8.9,and 105.6±9.4-178.3±17.8 ka.Six glacial advances in this region have been confirmed,which are equivalent in age to the Little Ice Age(LIA) ,Neoglaciation,marine oxygen isotope stages(MIS) 2,mid-MIS3,MIS4,and MIS6.The largest local last glacial maximum(LGML) occurred during MIS4 rather than the global Last Glacial Maximum(LGMG) of MIS2,and a glacial advance that occurred during mid-MIS3 was also larger than the LGMG.Furthermore,deeply weathered tills below 3500 m a.s.l.on the western slope of Kongur Mountain,when compared with the ages of the oldest glaciation of the Muztag Ata region,likely occurred prior to the penultimate glacial cycle.The glacial landforms prior to the penultimate glacial cycle on the northern slope are not well-preserved due to erosion after deposition. Several glacial deposits are only speculated to be distributed at higher elevations on the southwest side of the Gaizi Checkpoint. The extensive hummocky moraines on the western slope were formed by multiple glacial advances,and the latest glacial advance corresponded to mid-MIS3. 展开更多
关键词 Kongur Mountain glacial geomorphology ESR dating Quaternary glaciation hummocky moraine
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