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| 1 | Numerical modeling of concrete hydraulic fracturing with extended finite element method显示文摘The extended finite element method (XFEM) is a new numerical method for modeling discontinuity. Research about numerical modeling for concrete hydraulic fracturing by XFEM is explored. By building the virtual work principle of the fracture problem considering water pressure on the crack surface, the governing equations of XFEM for hydraulic fracture modeling are derived. Implementation of the XFEM for hydraulic fracturing is presented. Finally, the method is verified by two examples and the advan- tages of the XFEM for hydraulic fracturing analysis are displayed. | REN QingWen DONG YuWen YU TianTang | 2009 | Science China(Technological Sciences)2009，52，3： | 29 |
| 2 | Structural Analyses of Short-Chain Prenyltransfemses Identify an Evolutionarily Conserved GFPPS Clade in Brassicaceae Plants显示文摘Terpenoids 是专业化植物的代谢物的最大、很多样的类,它在植物开发期间在多样的生理的进程工作。在植物 terpenoids 的生合成,短链的 prenyltransferases (SC 磅) 和萜烯 synthases (TPS ) ,在决定 terpenoid 的 playcritical 角色差异。有不同的链长度的 SC 磅 biosynthesize prenyl 焦磷酸盐,和这些混合物是 terpenoids 的直接先锋。Arabidopsis thaliana 拥有其功能清楚地不被知道的 SC 磅的亚群。在这研究,我们集中于 10 geranylgeranyl 焦磷酸盐象 synthase 一样[GGPPSL ] 蛋白质,它通常被认为生产 GGPP [C20 ] 。我们发现 Arabidopsis GGPPSL 基因家庭的成员的一个子集经历了 neo-functionalization:GGPPSL6, 7, 9,和 10 主要举办 geranylfarnesyl 焦磷酸盐 synthase 活动(C25;renamedAtGFPPS1, 2, 3,和 4 ) ,并且 GGPPSL8 生产甚至更长的链 prenyl 焦磷酸盐(≥C30;renamedpolyprenyl 焦磷酸盐 synthase 2, AtPPPS2 ) 。由解决 AtGFPPS2, AtPPPS2,和 AtGGPPS11 的水晶结构,我们揭示 SC 磅的产品链长度决心机制并且作为 “three floors” 解释它当模特儿。用这个模型,我们识别了在 Brassicaceae 植物散布并且发现 GFPPS 基因典型地与编码 TPS 的基因一起发生的新奇 GFPPS clade,形成 GFPPS-TPS 基因簇。 | ChengyuanWang Qingwen Chen Dongjie Fan Jianxu Li Guodong Wang Peng Zhang | 2016 | Molecular Plant2016，9，2： | 19 |
| 3 | Heteromeric Geranyl(geranyi) Diphosphate Synthase Is Involved in Monoterpene Biosynthesis in Arabidopsis Flowers显示文摘Dear Editor, Monoterpenes,together with sesquiterpenes,play varying roles in plant interactions with the environment depending on the organs in which they are produced;these compounds likely function to attract pollinators when they are present in flowers and can protect plants against herbivores or microbes when produced in leaves or in roots.It is well known that geranyl diphosphate (GPP),the common precursor of monoterpenes,is biosynthesized by geranyl diphosphate synthase (GPPS). | Qingwen Chen Dongjie Fan GuodongWang | 2015 | Molecular Plant2015，8，9： | 14 |
| 4 | Research advance in safety analysis methods for high concrete dam显示文摘High tensile stresses occurred in high concrete dams and in their foundation lead to the growing importance of their safety with the increase of concrete dam height. Without any exiting specification or successful experiences of concrete dams up to 300 m at home and abroad for reference, experts feel obliged to figure out how to perform safety analysis on high concrete dam. This paper involves the main contents and mechanical features of the safety analysis on high concrete dam and shows the current state and progress of the analysis methods. For the insufficiency and problems existing in normative methods, study on modern numerical method such as finite element method must be strengthened to find out the stress control criterion which is in accordance with the methods. Two aspects of the safety analysis of high dam—— local damage from material level and integral destruction from structure level——should be considered. For the local damage, we should consider the non-homogeneity of material and strengthen the research of meso-damage mechanics. While for integral destruction of the system of high dam and its foundation, a study on non-strength theory should receive enough concerns. Further, attention should be paid to the research on the failure modes and criterions of high concrete dam failure analysis and safety evaluation, and the effect of uncertainty and classification of safety should be considered too. | REN QingWen XU LanYu WAN YunHui | 2007 | Science China(Technological Sciences)2007，50，z1： | 12 |
| 5 | Recently duplicated sesterterpene(C25) gene clusters in Arabidopsis thaliana modulate root microbiota显示文摘Land plants co-speciate with a diversity of continually expanding plant specialized metabolites(PSMs) and root microbial communities(microbiota).Homeostatic interactions between plants and root microbiota are essential for plant survival in natural environments.A growing appreciation of microbiota for plant health is fuelling rapid advances in genetic mechanisms of controlling microbiota by host plants.PSMs have long been proposed to mediate plant and single microbe interactions.However,the effects of PSMs,especially those evolutionarily new PSMs,on root microbiota at community level remain to be elucidated.Here,we discovered sesterterpenes in Arabidopsis thaliana,produced by recently duplicated prenyltransferase-terpene synthase(PT-TPS) gene clusters,with neo-functionalization.A single-residue substitution played a critical role in the acquisition of sesterterpene synthase(sesterTPS) activity in Brassicaceae plants.Moreover,we found that the absence of two root-specific sesterterpenoids,with similar chemical structure,significantly affected root microbiota assembly in similar patterns.Our results not only demonstrate the sensitivity of plant microbiota to PSMs but also establish a complete framework of host plants to control root microbiota composition through evolutionarily dynamic PSMs. | Qingwen Chen Ting Jiang Yong-Xin Liu Haili Liu Tao Zhao Zhixi Liu Xiangchao Gan Asis Hallab Xuemei Wang Juan He Yihua Ma Fengxia Zhang Tao Jin M. Eric Schranz Yong Wang Yang Bai Guodong Wang | 2019 | Science China(Life Sciences)2019，62，7： | 11 |
| 6 | Internal solitons in the northern South China Sea from insitu observations显示文摘In this paper, we demonstrate the characteris- tics of strong internal solitons at the southern edge of Dong- sha Islands in the northern South China Sea (SCS) during May―June 1998, using in situ time series data from the con- ductivity temperature depth (CTD), acoustic Doppler current profiler (ADCP) and thermistor chain. Our measurements indicated that the strongest internal solitons were larger than 90 m in wave amplitude, and propagated approximately westward in traveling direction, with the maximum current speed of about 2 m/s and the period of 10―20 min. The strongest internal solitons occurred noticeably during May 14―16, 1998, which is consistent with the occurrence period of the diurnal-dominated spring internal tides. | FANG Wendong SHI Ping LONG Xiaomin MAO Qingwen | 2005 | Chinese Science Bulletin2005，50，15： | 10 |
| 7 | Hierarchical Magnetic Network Constructed by CoFe Nanoparticles Suspended Within “Tubes on Rods” Matrix Toward Enhanced Microwave Absorption显示文摘Hierarchical magnetic-dielectric composites are promising functional materials with prospective applications in microwave absorption(MA)field.Herein,a three-dimension hierarchical“nanotubes on microrods,”core–shell magnetic metal–carbon composite is rationally constructed for the first time via a fast metal–organic frameworksbased ligand exchange strategy followed by a carbonization treatment with melamine.Abundant magnetic CoFe nanoparticles are embedded within one-dimensional graphitized carbon/carbon nanotubes supported on micro-scale Mo2N rod(Mo2N@CoFe@C/CNT),constructing a special multi-dimension hierarchical MA material.Ligand exchange reaction is found to determine the formation of hierarchical magnetic-dielectric composite,which is assembled by dielectric Mo2N as core and spatially dispersed CoFe nanoparticles within C/CNTs as shell.Mo2N@CoFe@C/CNT composites exhibit superior MA performance with maximum reflection loss of−53.5 dB at 2 mm thickness and show a broad effective absorption bandwidth of 5.0 GHz.The Mo2N@CoFe@C/CNT composites hold the following advantages:(1)hierarchical core–shell structure offers plentiful of heterojunction interfaces and triggers interfacial polarization,(2)unique electronic migration/hop paths in the graphitized C/CNTs and Mo2N rod facilitate conductive loss,(3)highly dispersed magnetic CoFe nanoparticles within“tubes on rods”matrix build multi-scale magnetic coupling network and reinforce magnetic response capability,confirmed by the off-axis electron holography. | Chunyang Xu Lei Wang Xiao Li Xiang Qian Zhengchen Wu Wenbin You Ke Pei Gang Qin Qingwen Zeng Ziqi Yang Chen Jin Renchao Che | 2021 | Nano-Micro Letters2021，13，3： | 10 |
| 8 | Ecosystem service tradeoff between traditional and modern agriculture: a case study in Congjiang County, Guizhou Province, China显示文摘 | Dan ZHANG Qingwen MIN Moucheng LIU Shengkui CHENG | 2012 | Frontiers of Environmental Science & Engineering2012，6，5： | 9 |
| 9 | GIAHS Project and Its Implementation in China显示文摘GIAHS Project and Concept In 2002,Food and Agriculture Organization of the United Nations(hereafter FAO)started an initiative for the conservation and adaptive management of Globally Important Agricultural Heritage Systems(abbreviated as GIAHS) to safeguard and support world’s agro-cultural | MIN Qingwen~1,SUN Yehong~(1,2) and SHI Yuanyuan~1 1.Institute of Geographic Sciences and Natural Resources Research,CAS,Beijing 100101,China 2.Graduate University of Chinese Academy of Sciences,Beijing 100049,China | 2010 | Journal of Resources and Ecology2010，1，1： | 9 |
| 10 | Improving the accuracy of image-based forest fire recognition and spatial positioning显示文摘Forest fires are frequent natural disasters.It is necessary to explore advanced means to monitor,recognize and locate forest fires so as to establish a scientific system for the early detection,real-time positioning and quick fighting of forest fires.This paper mainly expounds methods and algorithms for improving accuracy and removing uncertainty in image-based forest fire recognition and spatial positioning.Firstly,we discuss a method of forest fire recognition in visible-light imagery.There are four aspects to improve accuracy and remove uncertainty in fire recognition:(1)eliminating factors of interference such as road and sky with high brightness,red leaves,other colored objects and objects that are lit up at night,(2)excluding imaging for specific periods and azimuth angles for which interference phenomena repeatedly occur,(3)improving the thresholding method for determining the flame border in image processing by adjusting the threshold to the season,weather and region,and (4)integrating the visible-light image method with infrared image technology.Secondly,we examine infrared-image-based methods and approaches of improving the accuracy of forest fire recognition by combining the spectrum threshold with an object feature value such as the normalized difference vegetation index and excluding factors of disturbance such as interference signals,extreme weather and high-temperature animals.Thirdly,a method of visible analysis to enhance the accuracy of forest fire positioning is examined and realized;the method includes decreasing the visual angle,selecting central points,selecting the largest spots,and judging the selection of fire spots according to the central distance.Case studies are examined and the results are found to be satisfactory. | JIANG LiLi 1,QI QingWen 1,ZHANG An 1,GUO ChaoHui 2 & CHENG Xi 1,3 1 Institute of Geographical Sciences and Natural Resources Research,Chinese Academy of Sciences,Beijing 100101,China 2 China Center for Resources Satellite Data and Applications,Beijing 100094,China 3Graduate University of Chinese Academy of Sciences,Beijing 100049,China | 2010 | Science China(Technological Sciences)2010，53，S1： | 9 |
| 11 | Evaluation of water resources conserved by forests in the Hani rice terraces system of Honghe County,Yunnan,China:an application of the fuzzy comprehensive evaluation model显示文摘The Hani Rice Terraces System, based on gravity-flow irrigation, is one of the Globally Important Agricultural Heritage Systems(GIAHS) pilot sites selected by FAO in 2010. The water resource plays an important role in the sustainable development of this system. The value of water conserved by the forest is influenced by natural, economic and social factors. In this paper, the water quality, per capita water resources, per capita GDP and population density are chosen as indices to construct an index system for a comprehensive evaluation of water resources value. The weights of these indices are 0.443, 0.31, 0.141 and 0.106 respectively, which are determined by the analytic hierarchy process(AHP) method. The water resources value has been assessed by the fuzzy comprehensive evaluation model. The results show that the water resources value in the Hani Rice Terraces System is 4.25 RMB/m^3. Evaluating the value of water resources in the Hani Rice Terraces System can provide a reference for ecological compensation, for raising public awareness of the importance of protecting the system, and ultimately achieving its sustainable development. | LI Jing MIN Qingwen LI Wenhua BAI Yanying YANG Lun Dhruba Bijaya G C | 2016 | Journal of Mountain Science2016，13，4： | 8 |
| 12 | Dynamic response of gravity dam model with crack and damage detection显示文摘Gravity dam is a typical structure that has been frequently used in the fields of water conservancy engineering, and the safety of the structure has received widespread attention recently. Due to earthquakes or other reasons, gravity dams normally have damage such as cracks in practical service. Damage in the structures can alter the structural dynamic behavior and seriously affect structural performance. Maintaining safety and integrity of the gravity dam structures requires a better understanding of dynamic response of structure with damage and associated damage detection method. In order to study thoroughly the dynamic behavior of gravity dam with damage, the sweep vibration responses of the gravity dam with and without damage are investigated. The experimental results show that the peak-peak acceleration responses all increase for the structure is with crack. At the same time, a structural damage detection method, i.e., the local damage factor (LDF) method, is considered in the study of gravity dam damage detection when the dam is subjected to the base excitation. It is shown that the LDF method can be used as a damage index and is capable of evaluating both the presence and relative severity of structural damage, and it can be used as a viable condition assessment and damage identification technique to detect and quantify the damage in the gravity dam. | WANG ShanShan REN QingWen | 2011 | Science China(Technological Sciences)2011，54，3： | 8 |
| 13 | Experimental research and numerical simulation of RC beams strengthened with bonded steel plates显示文摘It is a common method to strengthen the damaged RC structures with bonded steel plates. At present the ultimate bearing ca- pacity of RC structures strengthened with bonded steel plates is calculated mostly using the theory based on the test. Four beams, including one reference beam, two strengthened concrete beams in primary force and secondary force respectively, and one strengthened concrete beam which was not anchored enough, were tested under four-point bending (4PB) in order to get the data of strain of longitudinal bars, bonded bottom steel plate in tension and deflection of beams in the middle span. The experimental program was supported by a three-dimensioned finite analysis using ABAQUS. At the end of experiments and finite analysis, it is concluded that the investing strengthening technique can significantly improve the load-carrying capacity and the phenomenon of stress concentration at the end of interface, as well as the damage at interface, can be well simulated with cohesive element provided by ABAQUS. | LEI Dong CHEN GuangYuan CHEN YuQuan REN QingWen | 2012 | Science China(Technological Sciences)2012，55，12： | 8 |
| 14 | Geographical genetic diversity and divergence of common wild rice (O. rufipogon Griff.) in China显示文摘Using 36 SSR markers and 889 accessions of common wild rice in China, the genetic diversity and the divergence among different geographical populations are investigated. Guangdong Province has the largest number of alleles, which account for 84% of the total alleles detected in the study, followed by Guangxi Province. The Nei's gene diversity indices, from high to low, are in the sequence of Hainan, Guangdong, Guangxi, Fujian, Hunan, Jiangxi, and Yunnan provinces. Two genetic diversity centers of Chinese common wild rice are detected on the basis of geographic analysis, i.e., the region covering Boluo, Zijin, Lufeng, Haifeng, Huidong and Huiyang counties of Guangdong Province and the region covering Yongning, Longan, Laibin and Guigang counties of Guangxi Province. The common wild rice in Yunnan, Hunan, Jiangxi, and Fujian provinces are diverged into respectively independent populations with relatively large genetic distances, whereas, those in Hainan, Guangdong and Guangxi provinces have relatively low genetic divergence. Under the condition of geographic separation, natural selection is considered as one of the primary forces contributing to the divergence of common wild rice in China. | WANG MeiXing ZHANG HongLiang ZHANG DongLing PAN DaJian LI DaoYuan FAN ZhiLan QI YongWen SUN JunLi YANG QingWen LI Chen LI ZiChao | 2008 | Chinese Science Bulletin2008，53，22： | 8 |
| 15 | Relationship between local damage and structural dynamic behavior显示文摘Damage in the structures alters the structural dynamic behavior. Damage generally occurs locally in the components of structures, and its effect often exhibits in the changes of both local and global characteristics of structures. Better understanding of this relationship helps to monitor and assess the condition of structures and develop dynamics-based structural health monitoring techniques. In this study, the relationship between the local damage and structural dynamic behavior is investigated. To validate the concept, an experiment of a three-dimensional (3-D) steel frame structure with different magnitudes of local damage is illustrated. The experimental results indicate that the change of global resonant response between the intact and damage structure is not obvious. The change of local resonant responses measured near the location of saw-cut crack damage is quite significant. The experimental study conducted indicates that the local resonant responses at the low order resonance can be used as an effective damage identification method to detect and quantify the local damage in the 3D frame structures. | WANG ShanShan REN QingWen | 2012 | Science China(Technological Sciences)2012，55，12： | 7 |
| 16 | Dynamical Mechanisms of Effects of Landslides on Long Distance Oil and Gas Pipelines显示文摘According to the investigations on the oil and gas pipelines such as the Lan-Cheng-Chong pipeline and the Southwest pipeline, there are two ways of laying pipeline: pipelines paralleling (approximately) to the main slide direction and pipelines perpendicular (approximately) to the main slide direction. If earth-retaining walls have been built for pipelines paralleling to the main slide direction, they will prevent the lands from sliding; On the contrary, without earth-retaining walls, the sharp broken rocks in the backfilling soil will scratch the safeguard of the pipeline when the landslides take place. Pipelines perpendicular to the main slide direction can be classified into four types according to the relative positions between pipelines and landslides: Pipelines over the slide planes, pipelines inside the fracture strips of slide planes, pipelines below the slide planes and pipelines behind the backsides of landslides. The different dynamical mechanisms of the process in which landslide acts against pipelines are analyzed based on whether the pipelines are equipped with fixed frusta, because the sliding resistance depends on whether and how many fixed frusta are equipped and the distance between frusta. | MA Qingwen WANG Chenghua KONG Jiming | 2006 | Wuhan University Journal of Natural Sciences2006，11，4： | 7 |
| 17 | A highly porous animal bone-derived char with a superiority of promoting nZVI for Cr(Ⅵ)sequestration in agricultural soils显示文摘Paddy soil and irrigation water are commonly contaminated with hexavalent chromium[Cr(Ⅵ)]near urban industrial areas,thereby threatening the safety of agricultural products and human health.In this study,we develop a porous and high specific area bone char(BC)to support nanoscale zero-valent iron(n ZVI)and apply it to remediate Cr(Ⅵ)pollution in water and paddy soil under anaerobic conditions.The batch experiments reveal that BC/n ZVI exhibits a higher removal capacity of 516.7 mg/(g·n ZVI)for Cr(Ⅵ)than n ZVI when normalized to the actual n ZVI content,which is 2.8 times that of n ZVI;moreover,the highest n ZVI utilization is the n ZVI loading of 15%(BC/n ZVI15).The Cr(Ⅵ)removal efficiency of BC/n ZVI15 decreases with increasing p H(4–10).Coexisting ions(phosphate and carbonate)and humic acid can inhibit the removal of Cr(Ⅵ)with BC/n ZVI15.Additionally,BC exhibits a strong advantage in promoting Cr(Ⅵ)removal by n ZVI compared to the widely used biochar and activated carbon.Our results demonstrate that reduction and coprecipitation are the dominant Cr(Ⅵ)removal mechanisms.Furthermore,BC/n ZVI15 shows a significantly higher reduction and removal efficiency as well as a strong anti-interference ability for Cr(Ⅵ)in paddy soil,as compared to n ZVI.These findings provide a new effective material for remediating Cr(Ⅵ)pollution from water and soil. | Kai Liu Fangbai Li Qingwen Tian Chengrong Nie Yibing Ma Zhenlong Zhu Liping Fang Yuanying Huang Siwen Liu | 2021 | Journal of Environmental Sciences2021，33，6： | 7 |
| 18 | Definition of the general initial water penetration fracture criterion for concrete and its engineering application显示文摘A general initial water penetration(seepage) fracture criterion for concrete is proposed to predict whether or not harmful water penetration(hydraulic fracturing),other than microcracking,will occur in concrete structures in a severe high water pressure environment.The final regression,of the different macroscopic failure types in concrete to microscopic ModeⅠ c racking,allows the use of only one universal criterion to indicate the damage.Thus,a general initial water penetration fracture criterion is approximately defined as a strain magnitude of 1000×10-6,based on the concept of tensile strain derived from experimental results in the relevant literature.Then,the locations of harmful water penetration fracture(hydraulic fracture) in the high arch dam mass of the Jinping first class hydropower project are analyzed using the nonlinear finite element method(FEM) according to the proposed criterion.The proposed criterion also holds promise for other concrete structures in high water pressure environments. | JIANG YaZhou REN QingWen XU Wei LIU Shuang | 2011 | Science China(Technological Sciences)2011，54，6： | 6 |
| 19 | Characteristics of Fe-based WC Composite Coatings Prepared by Double-pass Plasma Cladding Process显示文摘The Fe-based WC composite coatings were clad on Q235 steel by double-pass plasma cladding method,in which the WC-Co(WC covered with cobalt:78wt%WC,12wt%Co)doping was about 10wt%,20wt%and 40wt%,respectively.The microstructure and wear performance of the composite coatings were investigated by X-ray diffraction(XRD),scanning electron microscope(SEM),energy dispersive spectrometer(EDS)and ball-disc wear tests.The results show that the clad coatings contain mainly?-Fe,WC and carbides(Cr23C6,Fe3W3C-Fe4W2C)phases and the precipitation of carbides increases with the increase of WC-Co doping content.The WC-Co doping content has an obvious effect on the microstructure of the clad coatings.For the clad coatings with low WC-Co doping,the microstructure gradually transforms from planar crystal at the interface of substrate/coating to cell/dendritic crystal at the middle and the upper portion of the coatings.But there are a number of fishbone-like structure at the middle and the upper portion of clad coating with 40wt%WC-Co doping.The microstructure at the top is smaller than that at the bottom for all the coatings.The maximum of hardness of the clad coatings is 72.3HRC which is about 6.9 as much as the hardness of Q235 steel substrate.The composite coatings have good wear resistance due to the reinforcement of carbide particles and the strong bonding between carbide particles and ferroalloy.The suitable increase of WC-Co doping content can improve the wear resistance of the composite coatings. | Jiang Shaoqun Ren Qingwen Ying, Ding Gang, Wang Yu, Yi Wang Zehua Zhou Zehua | 2012 | 稀有金属材料与工程2012，41，S1： | 6 |
| 20 | Red/orange dual-emissive carbon dots for pH sensing and cell imaging显示文摘The dual-emissive N,S co-doped carbon dots (N,S-CDs) with a long emission wavelength were synthesized via solvothermal method.The N,S-CDs possess relatively high photoluminescence (PL) quantum yield (QY) (35.7%) towards near-infrared fluorescent peak up to 648 nm.With the advanced characterization techniques including X-ray photoelectron spectroscopy (XPS),Fourier transform infrared spectroscopy (FTIR),etc.It is found that the doped N,S elements play an important role in the formation of high QY CDs.The N,S-CDs exist distinct pH-sensitive feature with reversible fluorescence in a good linear relationship with pH values in the range of 1.0-13.0.What is more,N,S-CDs can be used as an ultrasensitive Ag+ probe sensor with the resolution up to 0.4 μM.This finding will expand the application of as prepared N,S-CDs in sensing and environmental fields. | Miaoran Zhang Rigu Su Jian Zhong Ling Fei Wei Cai Qingwen Guan Weijun Li Neng Li Yusheng Chen Lulu Cai Quan Xu | 2019 | Nano Research2019，12，4： | 6 |
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