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Revealed comparative advantage and competitiveness of China’s agricultural products 被引量:2
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作者 詹晶 《Agricultural Science & Technology》 CAS 2005年第1期10-13,共4页
This paper deals with the competitiveness of Chinese agricultural products, base on the index of revealed comparative advantage (RCA) using lots of data for the period of 1980 to 2003. The index is useful in identifyi... This paper deals with the competitiveness of Chinese agricultural products, base on the index of revealed comparative advantage (RCA) using lots of data for the period of 1980 to 2003. The index is useful in identifying the demarcation between comparative advantage and comparative disadvantage. The research indicates that some agro-products in China such as edible vegetables and tea have a comparative advantage, but the RCA values have been declining over the 24-year period, which has vast impacts on future reform in China’s agricultural structure. 展开更多
关键词 agricultural product EXPORT revealed comparative advantage (RCA) competitiveness.
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Comparative Genomic Analysis of Enterovirus 71 Revealed Six New Potential Neurovirulence-associated Sites 被引量:6
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作者 JIA Qing Jun CHEN Xin Yu +4 位作者 LI De Zhou XU Juan Juan XU Zhi Gang DUAN Zhi Liang WEN Jin Sheng 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2016年第10期767-772,共6页
In the present study,the complete genomes of four common(4/EV71/Wenzhou/CHN/2014,15/EV71/Wenzhou/CHN/2014,116/EV71/Wenzhou/CHN/2014,and 120/EV71/Wenzhou/CHN/2014)and two virulent(11/EV71/Wenzhou/CHN/2014and 109/EV7... In the present study,the complete genomes of four common(4/EV71/Wenzhou/CHN/2014,15/EV71/Wenzhou/CHN/2014,116/EV71/Wenzhou/CHN/2014,and 120/EV71/Wenzhou/CHN/2014)and two virulent(11/EV71/Wenzhou/CHN/2014and 109/EV71/Wenzhou/CHN/2014)enterovirus 71(EV71)isolates were sequenced and described.They are 7405 bp in length and belong to EV71 sub-genotype C4 (C4a cluster). 展开更多
关键词 CHN UTR EV Comparative Genomic Analysis of Enterovirus 71 revealed Six New Potential Neurovirulence-associated Sites
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Possible Nodeless Superconducting Gaps in Bi_2Sr_2CaCu_2O_(8+δ) and YBa_2Cu_3O_(7-x) Revealed by Cross-Sectional Scanning Tunneling Spectroscopy 被引量:2
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作者 任明强 闫亚军 +1 位作者 张童 封东来 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第12期124-128,共5页
Pairing in the cuprate high-temperature superconductors and its origin remain among the most enduring mysteries in condensed matter physics. With cross-sectional scanning tunneling microscopy/spectroscopy, we clearly ... Pairing in the cuprate high-temperature superconductors and its origin remain among the most enduring mysteries in condensed matter physics. With cross-sectional scanning tunneling microscopy/spectroscopy, we clearly reveal the spatial-dependence or inhomogeneity of the superconducting gap structure of Bi2Sr2CaCu2O8+δ (Bi2212) and YBa2Cu3O7-x (YBCO) along their c-axes on a scale shorter than the interlayer spacing. By tunneling into the (100) plane of a Bi2212 single crystal and a YBCO film, we observe both U-shaped tunneling spectra with extended fiat zero-conductance bottoms, and V-shaped gap structures, in different regions of each sample. On the YBCO film, tunneling into a (110) surface only reveals a U-shaped gap without any zero-bias peak. Our analysis suggests that the U-shaped gap is likely a nodeless superconducting gap. The V-shaped gap has a very small amplitude, and is likely proximity-induced by regions having the larger U-shaped gap. 展开更多
关键词 of is in revealed by Cross-Sectional Scanning Tunneling Spectroscopy and YBa2Cu3O Possible Nodeless Superconducting Gaps in Bi2Sr2CaCu2O by DOS on BI Cu Sr
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Common Electronic Features and Electronic Nematicity in Parent Compounds of Iron-Based Superconductors and FeSe/SrTiO_3 Films Revealed by Angle-Resolved Photoemission Spectroscopy 被引量:1
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作者 刘德发 赵林 +22 位作者 何少龙 胡勇 沈兵 黄建伟 梁爱基 徐煜 刘旭 何俊峰 牟代翔 刘单于 刘海云 刘国东 张文号 李坊森 马旭村 薛其坤 陈仙辉 陈根富 俞理 张君 许祖彦 陈创天 周兴江 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第7期152-156,共5页
We report comprehensive angle-resolved photoemission investigations on the electronic structures and nematicity of the parent compounds of the iron-based superconductors including CeFeAsO, BaFe2As2, NaFeAs, FeSe and u... We report comprehensive angle-resolved photoemission investigations on the electronic structures and nematicity of the parent compounds of the iron-based superconductors including CeFeAsO, BaFe2As2, NaFeAs, FeSe and undoped FeSe/SrTiO3 films with 1, 2 and 20 layers. While the electronic structure near tile Brillouin zone center F varies dramatically among different materials, the electronic structure near the Brillouin zone corners (M points), as well as their temperature dependence, are rather similar. The electronic structure near the zone corners is dominated by the electronic nematicity that gives rise to a band splitting of the dxz and dyz bands below the nematie transition temperature. A clear relation is observed between the band splitting magnitude arid the onset temperature of nematicity. Our results may shed light on the origin of nematicity, its effect on the electronic structures, and its relation with superconductivity in the iron-based superconductors. 展开更多
关键词 of on as or by Common Electronic Features and Electronic Nematicity in Parent Compounds of Iron-Based Superconductors and FeSe/SrTiO3 Films revealed by Angle-Resolved Photoemission Spectroscopy in ARPES As that
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Stem cells in the adult CNS revealed:examining their regulation by myelin basic protein 被引量:1
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作者 Wenjun Xu Nishanth Lakshman Cindi M.Morshead 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第12期1916-1917,共2页
Neural stem cells(NSCs)are found along the entire neuraxis,through development and into adulthood and old age(Sachewsky et al.,2014;Xu et al.,2016).There are two neurogenic niches in the adult CNS.One is the subgr... Neural stem cells(NSCs)are found along the entire neuraxis,through development and into adulthood and old age(Sachewsky et al.,2014;Xu et al.,2016).There are two neurogenic niches in the adult CNS.One is the subgranular zone in the hippocampus and the other is found in the periventricular region throughout the extent of the neuraxis(Barnabé-Heider et al.,2010;Mirzadeh et al.,2010). 展开更多
关键词 NSCS cell Stem cells in the adult CNS revealed CNS
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Combining Stated Preference and Revealed Preference Methods for the Valuation of Non-market Goods 被引量:1
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作者 Zhang Haipeng Xie Xuxuan 《Chinese Journal of Population,Resources and Environment》 2012年第4期121-126,共6页
In this paper,we introduce the combining stated preference and revealed preference methods which is the state-ofthe-art method for the valuation of non-market goods.Revealed preference methods and stated preference (S... In this paper,we introduce the combining stated preference and revealed preference methods which is the state-ofthe-art method for the valuation of non-market goods.Revealed preference methods and stated preference (SP) methods have both been applied by economists in valuing non-market goods;however both methods have inherent weaknesses.In order to exploit the strengths of the various approaches while minimizing their weaknesses,combining the two methods has become an important methodological option.Up to now,a growing number of literatures of studying combing the two types of data have evolved,and researchers developed three types of models to estimate combining revealed preference and stated preference data in academic fields:discrete choice model,continuous choice model and mixed choice model.Combining stated and revealed preference methods have been developed fast especially in the transport study field in which ideas could also be leant for environmental economic studies. 展开更多
关键词 stated preference revealed preference (RP) valuation of non-market goods
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Auditory Hopf Amplification Revealed by an Energy Method 被引量:1
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作者 Lin Tian Zhang-Cai Long 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第4期124-127,共4页
We report on the auditory Hopf amplification contributed by the electrical energy of the hair cell during its bundle deflecting. An energy method to calculate the active force is adopted according to the electrical en... We report on the auditory Hopf amplification contributed by the electrical energy of the hair cell during its bundle deflecting. An energy method to calculate the active force is adopted according to the electrical energy consumption of the hair cell. After some experimental data was analyzed and simulated, we find that the electrical energy determines the value of the active force and enlarges the mechanical response of the hair bundle. This amplification is controlled by the cell voltage and makes the sensor a Hopf vibrator with hearing nonlinear characteristics. A velocity-dependent active force derived previously from the force-gating channel operation strongly reinforces our conclusion. 展开更多
关键词 Auditory Hopf Amplification revealed by an Energy Method
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Organization and Ultra-Structural Components of Endothelial Surface Glycocalyx Revealed by Stochastic Optical Reconstruction Microscopy(STORM)
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作者 Jie Fan Yi Sun +2 位作者 Yifan Xia John M.Tarbell Bingmei M.Fua 《医用生物力学》 EI CAS CSCD 北大核心 2019年第A01期6-7,共2页
Introduction The endothelial cells(ECs)lining every blood vessel wall constantly expose to the mechanical forces generated by the blood flow.The EC responses to these hemodynamic forces play a critical role in the hom... Introduction The endothelial cells(ECs)lining every blood vessel wall constantly expose to the mechanical forces generated by the blood flow.The EC responses to these hemodynamic forces play a critical role in the homeostasis of the circulatory system.In addition to forming a transport barrier between the blood and vessel wall,vascular ECs play important roles in regulating circulation functions.Besides biochemical stimuli,blood flow induced(hemodynamic)mechanical stimuli,such as shear stress,pressure and circumferential stretch,modulate EC morphology and functions by activating mechanosensors,signaling pathways,and gene and protein expressions.The EC responses to the hemodynamic forces(mechano-sensing and transduction)are critical to maintaining normal vascular functions.Failure in the mechano-sensing and transduction leads to serious vascular diseases including hypertension,atherosclerosis,aneurysms and thrombosis,to name a few[1].On the luminal surface of our blood vessels,there is a thin layer called endothelial surface glycocalyx(ESG)which consists of proteoglycans,glycosaminoglycans(GAGs)and glycoproteins.The GAGs in the ESG are heparan sulfate(HS),hyaluronic acid(HA),chondroitin sulfate(CS),and sialic acid(SA)[2].In order to play important roles in vascular functions,such as being a mechanosensor and transducer for the endothelial cells(ECs)to sense the blood flow,a molecular sieve to maintain normal microvessel permeability and a barrier between the circulating cells and endothelial cells forming the vessel wall,the ESG should have an organized structure at the molecular level.Due to the limitations of optical and electron microscopy,the ultra-structure and organization of ESG has not been revealed until recent development of a super high resolution fluorescence optical microscope,STORM(Stochastic Optical Reconstruction Microscopy).The diffraction of a single fluorescence molecule can be described as the point spread function(PSF).When the light of wavelengthλexcites the fluorophore(emitter),the intensity profile of the spot is defined as the PSF with the width^0.6λ/NA,NA is the numerical aperture of the objective.The diffraction-limited image resolution,for a high numerical aperture objective lens,is^200 nm in the lateral direction and^500 nm in the axial direction,for a conventional fluorescence microscope.The key idea of the single-molecule localization microscopy is to light the molecule,in turn,to achieve the nanometer-level accuracy of their position and reconstruction into a super-resolution image,such as STORM.STORM employs photo-switching mechanisms to stochastically activate individual molecules(photo-switchable or photoactivatable fluorophores)within the diffraction-limited region at different times.Then images with sub-diffraction limit resolution are reconstructed from the measured positions of individual fluorophores[3].To trade the super spatial resolution(accuracy),STORM sacrifices its temporal resolution(efficiency)by switching the state and sequentially exciting the emitters at a high density.Rust et al[3]employed organic dyes and fluorescent proteins as photo-switchable emitters to trade temporal resolution for a super spatial resolution(~20 nm lateral and^50 nm axial at present,can go down to a couple of nanometers if using smaller peptides or antibody fragments instead of currently used whole anti-bodies),which is an order of magnitude higher than conventional confocal microscopy.In the current study,we employed STORM to reveal the major ultra-structural components of the ESG,HS and HA,and their organization at the surface of the cultured EC monolayer[4].Materials and methods We used newly acquired Nikon-STORM system to observe the ESG on in vitro EC(bEnd3,mouse brain microvascular endothelial cells)monolayers.After confluency,the bEnd3 cells were immunolabeled with anti-HS,fol-lowed by an ATT0488 conjugated goat anti-mouse IgG,and with biotinylated HA binding protein,followed by an AF647 conjugated anti-biotin.The ESG was then imaged by the STORM with a 100x/1.49 oil immersed lens.Multiple Reporters of ATT0488 and AF647 with alternating illumination were used to acquire the 3D images of HS and HA.The field of 256×256(40×40μm2)of HS and HA at the surface of ECs was obtained based on totally 40,000 of EM-CCD captured images for each reporter at a capturing speed of 19 ms/frame.Results HA is a long molecule weaving into a network which covers the endothelial luminal surface.The diameter of the HA segments is 185.3±44.7 nm,155.5±57.2 nm,and 156.9±56.1 nm,respectively,at the top,middle and bottom regions of the cell luminal surface.In contrast,HS is a shorter molecule,perpendicular to the cell surface.HA and HS are partially overlapped with each other at the endothelial luminal surface.We quantified the length,diameter,orientation,and density of HS at the top,middle and bottom regions of the endothelial surface.The diameter of the observed HS is 191.0±46.0 nm,284.3±71.1 nm,and 184.2±59.6 nm,and the length of the HS is 621.0±75.7 nm,651.0±118.0 nm,and 575.2±105.6 nm,respectively,at the top,middle and bottom regions of the cell luminal surface.For the HS orientation,its angle with the cell surface is 92.9±1.9,88.7±8.2,and 96.2±10.9 degree,respectively,at the top,middle and bottom regions.The angle of 90 degree is perfectly perpendicular to the cell surface.For the HS distribution,the average density is0.398 elements/μm2,0.345 elements/μm2 and 0.665 elements/μm2,respectively,and the distance between the adjacent HS is 1 694.4±628.1 nm,1 844.8±758.5 nm,and 1 221.9±450.7 nm,respectively,at the top,middle and bottom regions.Conclusions Our results suggest that HS plays a major role in mechanosensing and HA plays a major role in the molecular sieve,due to their organization,ultra-structure and distribution. 展开更多
关键词 ORGANIZATION Ultra-Structural Components ENDOTHELIAL Surface GLYCOCALYX revealed Optical Reconstruction Microscopy STORM
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Hybridization Effects Revealed by Angle-Resolved Photoemission Spectroscopy in Heavy-Fermion Ce2IrIn8
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作者 Haijiang Liu Yuanji Xu +9 位作者 Yigui Zhong Jianyu Guan Lingyuan Kong Junzhang Ma Yaobo Huang Qiuyun Chen Genfu Chen Ming Shi Yi-feng Yang Hong Ding 《Chinese Physics Letters》 SCIE CAS CSCD 2019年第9期36-40,共5页
We utilize high-resolution resonant angle-resolved photoemission spectroscopy(ARPES)to study the band structure and hybridization effect of the heavy-fermion compound Ce2 IrIn8.We observe a nearly flat band at the bin... We utilize high-resolution resonant angle-resolved photoemission spectroscopy(ARPES)to study the band structure and hybridization effect of the heavy-fermion compound Ce2 IrIn8.We observe a nearly flat band at the binding energy of 7 meV below the coherent temperature Tcoh^40 K,which characterizes the electrical resistance maximum and indicates the onset temperature of hybridization.However,the Fermi vector and the Fermi surface volume have little change around Tcoh,which challenges the widely believed evolution from a hightemperature small Fermi surface to a low-temperature large Fermi surface.Our experimental results of the band structure fit well with the density functional theory plus dynamic mean-field theory calculations. 展开更多
关键词 ARPES HYBRIDIZATION EFFECTS revealed by Angle-Resolved PHOTOEMISSION Spectroscopy in HEAVY-FERMION Ce2IrIn8 Ce
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Allosteric Mechanism of Calmodulin Revealed by Targeted Molecular Dynamics Simulation
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作者 梁倩云 庞春丽 +4 位作者 李军委 张素花 柳辉 展永 安海龙 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第6期121-125,共5页
Calmodulin (CAM) is involved in the regulation of a variety of cellular signaling pathways. To accomplish its physiological functions, CaM binds with Ca2+ at its EF-hand Ca2+ binding sites which induce the conform... Calmodulin (CAM) is involved in the regulation of a variety of cellular signaling pathways. To accomplish its physiological functions, CaM binds with Ca2+ at its EF-hand Ca2+ binding sites which induce the conformational switching of CaM. However, the molecular mechanism by which Ca2+ binds with CaM and induces conformational switching is still obscure. Here we combine molecular dynamics with targeted molecular dynamics simulation and achieve the state-transition pathway of CaM. Our data show that Ca2+ binding speeds up the conformational transition of CaM by weakening the interactions which stabilize the closed state. It spends about 6.5 ns and 5.25 ns for transition from closed state to open state for apo and holo CaM, respectively. Regarding the contribution of two EF-hands, our data indicate that the first EF-hand triggers the conformational transition and is followed by the second one. We determine that there are two interaction networks which contribute to stabilize the closed and open states, respectively. 展开更多
关键词 CA EF TMD Allosteric Mechanism of Calmodulin revealed by Targeted Molecular Dynamics Simulation
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Revealed Cores: Characterizations and Structure
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作者 Stefano Vannucci 《Applied Mathematics》 2015年第14期2279-2291,共13页
Characterizations of the classes of all choice functions that select the cores or the externally stable cores induced by an underlying revealed dominance digraph are provided. Relying on such characterizations, the ba... Characterizations of the classes of all choice functions that select the cores or the externally stable cores induced by an underlying revealed dominance digraph are provided. Relying on such characterizations, the basic order-theoretic structure of the corresponding sets of revealed cores is also analyzed. In particular, it is shown that the poset of all revealed cores ordered by set inclusion is a median meet semilattice: therefore, any profile of revealed cores may be aggregated by means of the simple majority rule. 展开更多
关键词 Core Choice Functions DOMINANCE DIGRAPHS revealed PREFERENCE
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Deep Drilling Campaign in the Western Qaidam Basin,NE Tibetan Plateau and their Revealed Global Temperature Forcing of Salt Formation in the Late Miocene-Quaternary
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作者 FANG Xiaomin LI Minghui +5 位作者 Erwin APPEL WANG Jiuyi HAN Wenxia ZHANG Weilin YANG Yibo CAI Maotang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期216-217,共2页
The Qaidam Basin in the NE Tibetan Plateau has contributed the largest amount of potash in China.However,how the potash was formed has long been a subject of debate.Here we carried out a deep drilling
关键词 SG Deep Drilling Campaign in the Western Qaidam Basin NE Tibetan Plateau and their revealed Global Temperature Forcing of Salt Formation in the Late Miocene-Quaternary NE
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Ryanodine receptor-protein regulator interaction revealed a general molecular mechanism of channel inhibition
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作者 Chang-Cheng Yin Department of Biophysics, Health Science Center, Peking University, 38 Xueyuan Road, Beijing 100191, 《生物物理学报》 CAS CSCD 北大核心 2009年第S1期79-79,共1页
Ryanodine receptors (RyR) are the major Ca2+ release channels in both cardiac and skeletal muscle, they play a crucial role in the Ca2+ signaling pathway that govern the
关键词 RyR Ryanodine receptor-protein regulator interaction revealed a general molecular mechanism of channel inhibition
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Possible Water and Ice on the Moon Revealed by Discovery of a Congeliturbated Fan
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作者 HAN Tonglin YU Changqing +1 位作者 CHEN Peng LIN Jingxing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第4期1535-1536,共2页
The nature of the Moon's surface has always been controversial. American scientists first suggested that there has been water and ice on the Moon (Watson et al., 1961), a hypothesis supported by some but not other ... The nature of the Moon's surface has always been controversial. American scientists first suggested that there has been water and ice on the Moon (Watson et al., 1961), a hypothesis supported by some but not other researchers (Compiling Committee, 2006; Ouyang, 2005; Wang, 2010). So whether there has been or is any water on the Moon or not, is a matter of heated debate. 展开更多
关键词 Possible Water and Ice on the Moon revealed by Discovery of a Congeliturbated Fan
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Best Chinese Cities for Expats in 2018 Revealed
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作者 Li Yiwen Feng Minghui 《国际人才交流》 2019年第5期72-72,共1页
The annual survey Amazing China-the Most Attractive Chinese Cities for Expats 2018 unveiled its results at the Shenzhen forum of the Conference on International Exchange of Professionals on April 14 in Shenzhen,South ... The annual survey Amazing China-the Most Attractive Chinese Cities for Expats 2018 unveiled its results at the Shenzhen forum of the Conference on International Exchange of Professionals on April 14 in Shenzhen,South China’s Guangdong province. Zhang Jianguo,Vice Minister of the Ministry of Science and Technology,announced the results. 展开更多
关键词 Best CHINESE CITIES for Expats in 2018 revealed
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Domestication process of yaks revealed
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《Bulletin of the Chinese Academy of Sciences》 2007年第1期12-13,共2页
In his monumental work “Origin of Species,” Charles Darwin suggested that all domestic animals originated from their wild an-
关键词 Domestication process of yaks revealed THAN
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China’s Women,Revealed
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作者 Maya Reid 《ChinAfrica》 2011年第3期48-49,共2页
A review of Bi Feiyu’s Three Sisters,now shortlisted for the Man Asian Literary Prize by Maya Reid BI Feiyu is reportedly inundated with interview requests from journalists every March asking him to comment on women... A review of Bi Feiyu’s Three Sisters,now shortlisted for the Man Asian Literary Prize by Maya Reid BI Feiyu is reportedly inundated with interview requests from journalists every March asking him to comment on women’s issues (March 8 is the International Women’s Day).And why not? The author has been referred to by many as "China’s best male writer on the female psyche." If his novel,Three Sisters,wins this year’s Man 展开更多
关键词 China’s Women revealed
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Fresh Clues about the Origin of Mammalian Middle Ear Revealed
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作者 (Song Jianlan) 《Bulletin of the Chinese Academy of Sciences》 2002年第1期7-8,共2页
  CAS paleontologists have identified a rod-like bone from two early Cretaceous mammals as ossified Meckel's cartilage (OMC). This clears some doubts on the controversial topic of the origin of definitive mannal...   CAS paleontologists have identified a rod-like bone from two early Cretaceous mammals as ossified Meckel's cartilage (OMC). This clears some doubts on the controversial topic of the origin of definitive mannalian middle ear (DMME).…… 展开更多
关键词 OMC Fresh Clues about the Origin of Mammalian Middle Ear revealed
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Mysteries of Science and Technology Revealed
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《China Today》 2000年第6期26-27,共2页
关键词 Mysteries of Science and Technology revealed
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Thermal spallation in rock revealed by ultraviolet laser-induced voltage 被引量:5
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作者 Jing Zhu HongLei Zhan +3 位作者 Kun Zhao XinYang Miao Qiong Zhou WenZheng Yue 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2019年第7期123-126,共4页
In the petroleum industry, perforation plays an important role in the exploitation of oil and gas and a considerable number of studies have been conducted with the objective of improving the recovery rates of oil and ... In the petroleum industry, perforation plays an important role in the exploitation of oil and gas and a considerable number of studies have been conducted with the objective of improving the recovery rates of oil and gas (1,2)Lasers have been used to drill holes in a wide variety of rock types with the advantages of feasibility, cost, benefits, and environmental impact as determined by the Gas Technology Institute [1]. 展开更多
关键词 LIV THERMAL SPALLATION in ROCK revealed by ULTRAVIOLET LASER-INDUCED voltage
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