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28篇 您的检索式:作者名="ZENG Junfeng"
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1Bottom water temperature measurements in the South China Sea,eastern Indian Ocean and western Pacific Ocean显示文摘文章报道了一批新的海底底水温度(BWT)数据,其中南海(SCS)158个站位、东印度洋(EIO)30个站位及西太平洋(WPO)37个站位。基于这批新的BWT数据,获得南海和西太平洋海域底水温度与水深经验关系,可为地球物理和物理海洋提供准确、可靠的海底温度边界。这将有助于海底油气资源调查与评估。同时,这批实测数据表明:1)水深超过3500m的海域,其底水温度在南海约为2.47℃,比东印度洋(~1.34℃)和西太平洋(~1.60℃)稍微偏高。这与大洋传送带模式所预测的情况比较吻合。该模式认为:低温高盐的海水,从北大西洋格陵兰岛和冰岛附近海域下沉到深层,然后向南流动,再与南极洲周围海域的低温高盐海水一同向北进入印度洋和太平洋。而南海是一个相对比较封闭的热带边缘海,其内部海水与印度洋和菲律宾海交换有限,导致海水温度整体高于印度洋和太平洋。2)台西南盆地水深在2700~3000m的部分站位,其底水温高达约3.00℃,明显高于其周边同水深海域底水温度(平均值约为2.33℃)。这可能是台西南盆地海底水热活动导致的结果。3)在东印度洋和西太平洋水深超过4800m海域,底水温度随着水压增大稍有升高,其升高率分别为10.6mK·MPa^(-1)和12.0mK·MPa^(-1)。这与理论估算的深层底水绝热压力温度梯度范围较为吻合。这也意味着东印度洋和西太平洋深层底水,主要由绝热自压作用导致其温度随着深度的增大而升高。YANG Xiaoqiu SHI Xiaobin ZHAO Junfeng YU Chuanhai GAO Hongfang CHEN Aihua LU Yuanzheng CEN Xianrong LIN Weiren ZENG Xin XU Hehua REN Ziqiang ZHOU Shengqi XU Ziying SUN Jinlong KAMIYA Nana LIN Jian 2018热带海洋学报2018,37,5:8
2High-pressure granulite from Western Kunlun,northwestern China:Its metamorphic evolution,zircon SHRIMP U-Pb ages and tectonic implication显示文摘High-pressure mafic granulites occurring as lenticular bodies within garnet-amphibolites in Kangxiwar Fault have been first reported in this paper. The P-T conditions of two metamorphic stages were ob-tained using calibrated geothermal barometers and ThermoCalc Program. The peak metamorphic con-dition of these high-pressure granulites is about 760―820℃,1.0―1.2 GPa and the retrograde meta-morphic condition is about 620―720℃,0.7―0.8 GPa. The petrological studies show that they have a near-isobaric cooling P-T path which suggests that the Western Kunlun underwent initial crustal thickening,subsequent exhumation and cooling. The SHRIMP zircon U-Pb dating gives two groups of ages for high-pressure granulites. One is 177±6 Ma which is obtained from the rim of the zircon. We consider this age should be the metamorphic age. And the other is 456±30 Ma which is obtained from the core of the zircon and should be the protolith age. The formation of these high-pressure granulites in western Kunlun is closely correlated with the evolution of the Paleo-Tethys and has important im-plications for the research on Tethys and Paleo-Asian tectonic zone.QU JunFeng ZHANG LiFei AI YongLiang L Zeng WANG JianPing ZHOU Hui WANG ShiYan 2007Science China Earth Sciences2007,50,7:7
3Designing high-strength titanium alloy using pseudo-spinodal mechanism through diffusion multiple experiment and CALPHAD calculation显示文摘This study used the pseudo-spinodal mechanism to obtain the ultrafineαphase for designing highstrength titanium alloy.Diffusion multiple experiments were designed to find the composition range of TM-x Mo-y V alloy(TM:Ti-4.5 Al-2 Cr-2.5 Nb-2 Zr-1 Sn)for obtaining ultrafineαphase.CALPHAD results confirm that when the alloy composition is located near the intersection of theαandβphase free energy curves,the alloy will undergo pseudo-spinodal transformation and obtain the ultrafineαphase.The designed TM-6 Mo-3 V alloy has a yield strength of 1411 MPa and an elongation of 6.5%.The strength of the alloy depends on the thickness,fraction of theαphase and the solid solution strengthening effect of the alloying elements.The deformation mechanism of the alloy is the dislocation slip of theαandβphases and the twin deformation of theαphase.The large number ofα/βinterfaces produced by the fineαphase is the main reason for limiting the ductility of the alloy.The use of the pseudo-spinodal mechanism combined with diffusion multiple experiments and CALPHAD is an effective method for designing high-strength titanium alloys.Di Wu Libin Liu Lijun Zeng Wenguang Zhu Wanlin Wang Xiaoyong Zhang Junfeng Hou Baoliang Liu Jiafeng Lei Kechao Zhou 2021Journal of Materials Science & Technology2021,,15:3
4Feasibility analysis of the angular momentum reversal trajectory via hodograph method for high performance solar sails显示文摘In this paper a new phase space of hodograph method is adopted to investigate and better understand the two-dimensional angular momentum reversal(H-reversal) trajectories for high performance solar sails within a fixed cone angle.As the hodograph method and the H-reversal trajectory are not very common,both of them are briefly introduced.The relationship between them are constructed and addressed with a sample trajectory.How the phase space varies according to the sail quality and the fixed sail cone angle is also studied.Through variation of the phase space,the minimum sail lightness number can be obtained by solving a set of algebraic equations instead of a parameter optimization problem.For a given sail lightness number,there are three types of the two-dimensional possible heliocentric motion,including the spiral inward trajectories towards the Sun,the H-reversal trajectories and the directly outward escape trajectories.The boundaries that separate these different groups are easily determined by using the phase space.Finally,the method and procedures to achieve the feasible region of the H-reversal trajectory with required perihelion distance are presented in detail.ZENG XiangYuan BAOYIN HeXi LI JunFeng GONG ShengPing 2011Science China(Technological Sciences)2011,54,11:3
5Generalized flyby trajectories around elongated minor celestial bodies as a rotating mass dipole显示文摘The aim of this paper is to understand the common characteristics of the generalized flyby trajectory around natural elongated bodies. Such flyby trajectories provide a short-term mechanism to clear away vicinal objects or temporally capture ejecta into circling orbits. The gravitational potential of elongated bodies is described by a unified approximate model, i.e., the rotating mass dipole which is two point masses connected with a constant massless rod The energy power is used to illustrate the flyby effect in terms of the instantaneous orbital energy. The essential of the single flyby trajectory is studied analytically, and the relationship between the flyby trajectory and its Jacobi integral is also illustrated. Sample trajectories are given to show the variational trend of the energy increment with respect to differen orbital periapsides. The distribution of natural ejecting orbits is presented by varying the parameters of the approximate model.Xiangyuan Zeng Baodong Fang Junfeng Li Yang Yu 2016Acta Mechanica Sinica2016,32,3:3
6Structural deformation, metallogenic epoch and genetic mechanism of the Woxi Au-Sb-W deposit, Western Hunan Province, South China显示文摘The remobilization,migration,precipitation,and enrichment of ore-forming elements are closely related to structures.Therefore,detailed regional and ore-field structural analyses are critical for determining the genesis of a mineral deposit.The Jiangnan Orogenic Belt(JOB)is an important gold polymetallic metallogenic belt in South China,which is characterized by multiple periods of gold mineralization in the Paleozoic and Mesozoic.However,the genesis of these gold polymetallic deposits is still not well understood due to a lack of systematic research on the regional geology,ore-controlling structures and metallogenic mechanism.In this study,a detailed structural survey at the surface and in the subsurface tunnels was conducted on the Woxi Au-Sb-W deposit,the genesis of which is relatively controversial among the gold polymetallic deposits in the JOB due to poor structural constraints.In addition,a wolframite U-Pb dating was carried out to further constrain the relationship between structures and mineralization.Based on the results of these studies,together with those from previous studies,it is proposed that the Woxi deposit and surrounding areas likely underwent six periods of regional deformation,which are constrained in time and geodynamic setting.Furthermore,we present a systematic discussion on the roles of ore-controlling structures in the transportation,distribution,and deposition of ore-forming elements and localization of orebodies.According to the wolframite dating results,structural analyses,and previous data,we propose that the Woxi Au-Sb-W deposit was formed in two stages during the Yanshanian:a W(wolframite)-Au mineralization stage at ca.140 Ma and an Au-Sb-W(scheelite)mineralization stage at<130 Ma.These mineralizing events are interpreted to have a tight relationship with tectonic reactivation,and the ore-forming fluids were derived from deep sources,including those of magmatic or metamorphic origins.The Woxi deposit can therefore be classified as an“intracontinental reactivation-type”,and the mineralization is related to lithospheric extension caused by plate retreat,retention,and delamination following the cessation of westward subduction of the Paleo-Pacific Plate beneath the East Asian continent.Bin LI Deru XU Daoyuan BAI Guoxiang CHI Junfeng DAI Cheng GAO Teng DENG Shaohao ZOU Wen MA Guojian WANG Yuexin LING Guangqian ZENG Yinmin LI 2022Science China Earth Sciences2022,65,12:2
7CD146 is a coreceptor for VEGFR-2 in tumor angiogenesis显示文摘Tianxia Jiang Jie Zhuang Hongxia Duan Yongting Luo Qiqun Zeng Kelong Fan Huiwen Yan Di Lu Zhongde Ye Junfeng Hao Jing Feng Dongling Yang Xiyun Yan 2012Blood2012,,11:1
8Effect of oxide scale on corrosion behavior of HP-13Cr stainless steel during well completion process显示文摘The well completion process in oil and gas industry,aiming to build effective exploitation,is divided into acidizing and formation water production process.Oxide scale(OS)formed on the inner wall of the HP-13Cr stainless steel tubes during the hot extrusion process changes the surface roughness.The effects of OS on the corrosion of HP-13Cr stainless steel during well completion process were studied by corrosion measurement,spectra analysis,microscopic observation and numerical simulation.The results indicate that the OS make no change of phase distribution and element composition of corrosion scale,while the increasing OS roughness is the dominant factor for accelerating corrosion rate during the well completion process.In acidizing process,the greater surface roughness OS of HP-13Cr stainless steel increases the corrosion rate obviously due to a larger interfacial area in contact with the aggressive environment.During subsequent formation water production process,the turbulence eddy,formed at locations characterized with greater surface roughness OS,can deteriorate the corrosion scale and accelerate the mass transfer of the corrosive species,resulting in more serious corrosion.Wenlong Qi Jidong Wang Xuanpeng Li Yanan Cui Yang Zhao Junfeng Xie Guanxin Zeng Qiuying Gao Tao Zhang Fuhui Wang 2021Journal of Materials Science & Technology2021,,5:1
9Correlates of extinction risk in Chinese endemic birds显示文摘Background: China has a relative high degree of endemism of birds due to its large area, diversified topography, and varied climates and habitats. Among the 77 Chinese endemic birds, 29 species are classified as threatened according to the officially released China Biodiversity Red List in 2015. Chinese endemic birds should be the focus of conservation because their local extinction in China means complete global extinction. However, to date, no study has explicitly examined the patterns and processes of extinction and threat in Chinese endemic birds. Methods: We obtained eleven biological traits and four extrinsic factors that are commonly hypothesized to influence extinction risk. After phylogenetic correction, these factors were used separately and in combination to assess their associations with extinction risk. Results: We found that 37.7% of Chinese endemic birds were listed as threatened (Vulnerable, Endangered and Critically Endangered). Small range size, high hunting vulnerability, and high human population density were important predictors of high extinction risk in Chinese endemic birds. Conclusions: Our study is the first to systematically investigate the patterns and processes of extinction risk in Chinese endemic birds. We suggest that endemic species with small range size and living in area with high human densities require conservation priorities. Conservation efforts should also focus on the reduction of human threats, such as human hunting and habitat degradation, for the effective preservation of Chinese endemic birds.Chuanwu Chen Di Zeng Yuhao Zhao Yiru Wu Junfeng Xu Yanping Wang 2019Avian Research2019,10,2:1
10The study of LVPO catalysts prepared by microwave methods 显示文摘 Jiang Huachang Niu Junfeng 2005J of Molecular Catalysis A: Chemical2005,232,12:1
11Bend family proteins mark chromatin boundaries and synergistically promote early germ cell differentiation显示文摘Understanding the regulatory networks for germ cell fate specification is necessary to developing strategies for improving the efficiency of germ cell production in vitro.In this study,we developed a coupled screening strategy that took advantage of an arrayed bi-molecular fluorescence complementation(BiFC)platform for protein-protein interaction screens and epiblast-like cell(EpiLC)-induction assays using reporter mouse embryonic stem cells(mESCs).Investigation of candidate interaction partners of core human pluripotent factors OCT4,NANOG,KLF4 and SOX2 in EpiLC differentiation assays identified novel primordial germ cell(PGC)-inducing factors including BEN-domain(BEND/Bend)family members.Through RNA-seq,ChIP-seq,and ATAC-seq analyses,we showed that Bend5 worked together with Bend4 and helped mark chromatin boundaries to promote EpiLC induction in vitro.Our findings suggest that BEND/Bend proteins represent a new family of transcriptional modulators and chromatin boundary factors that participate in gene expression regulation during early germline development.Guang Shi Yaofu Bai Xiya Zhang Junfeng Su Junjie Pang Quanyuan He Pengguihang Zeng Junjun Ding Yuanyan Xiong Jingran Zhang Jingwen Wang Dan Liu Wenbin Ma Junjiu Huang Zhou Songyang 2022Protein & Cell2022,13,10:1
12Experimental studies on extraction of cobalt ions from dilute aqueous solutions by using complexation-ultrafiltration process显示文摘The extraction of cobalt ions from dilute aqueous solutions was investigated by ultrafiltration with the help of poly(acrylic acid)sodium salt(PAASS).Polysulfone and polyethersulfone hollow fiber ultrafiltration membranes were employed in this process.The kinetics of complexation reaction was studied for PAASS with Co^(2+).Results showed that,under a large excess of PAASS,it takes 65,55 and 40 min at pH 5,6 and 7,respectively,to get the equilibrium of complexation.The reaction kinetics can be described by a pseudo-first-order equation.Then,the effects of various parameters on the extraction of Co^(2+)were examined in detail.Results indicated that loading ratio,pH value and low-molecular competitive complexing agent affect significantly cobalt rejection coefficient R.Furthermore,a concentration experiment was carried out at pH 7.With increasing volume concentration factor,membrane flux declines slowly,and R value is always about 1.The concentrated retentate was used further for a decomplexation experiment.The decomplexation ratio of cobalt-PAASS complex reaches as high as 90.1%.After the decomplexation step,a diafiltration experiment was performed at pH 2.5.Cobalt ions can be extracted satisfactorily from the retentate,and a purified PAASS is obtained.Jianxian ZENG Junfeng LIU Niandong HUANG 2010Frontiers of Chemical Science and Engineering2010,4,3:1
13Trajectory optimization and applications using high performance solar sails显示文摘The high performance solar sail can enable fast missions to the outer solar system and produce exotic non-Keplerian orbits.As there is no fuel consumption,mission trajectories for solar sail spacecraft are typically optimized with respect to flight time.Several investigations focused on interstellar probe missions have been made,including optimal methods and new objective functions. Two modes of interstellar mission trajectories,namely 'direct flyby' and 'angular momentum reversal trajectory',are compare...Xiangyuan Zeng,~(a)) Junfeng Li,~(b)) Hexi Baoyin,and Shengping Gong School of Aerospace,Tsinghua University,Beijing 100084,China 2011Theoretical & Applied Mechanics Letters2011,1,3:1
14Robotic gastrectomy versus laparoscopic gastrectomy for gastric cancer: comparison of surgical performance and short-term outcomes显示文摘Zhou Junfeng Shi Yan Tang Bo Hao Yingxue Zeng Dongzhu Zhao Yongliang Qian Feng Yu Peiwu 2014Surgical Endoscopy2014,,6:1
15Limited Feedback Bit Allocation for Cooperative Multi-cell Systems with Multi- user MIMO显示文摘For the cooperative multi-cell systems with multi-user MIMO, a new limited feedback bit allocation scheme is proposed to minimize the rate loss caused by quantization error. In the proposed scheme, the Channel State Information (CSI) feedback of cell-edge user for the local service cell and the adjacent interference cell are separately quantized. Based on the upper bound of the rate loss of cell-edge user due to the limited feedback, the number of feedback bits for quantized CSI of the local service cell and the adjacent cell are optimized with the fixed total bits of the limited feedback. The simulation shows that our proposed scheme of feedback bits allocation efficiently decreases the interference and increases the rate of systems compared with that of equal bits allocation and those of other allocations.Shi Junfeng Zhang Tiankui Zeng Zhimin 2012China Communications2012,9,1:1
16Taxonomic Revision of Raorchestes menglaensis(Kou,1990)(Amphibia:Anura),with Descriptions of Two New Species from Yunnan,China显示文摘Raorchestes is a group of Bush frogs mainly distributed in South and Southeast Asia that are poorly recognized by morphological criteria.We recognize the true R.menglaensis(Kou) based on 10 specimens newly collected from the type locality.An expanded description is also provided,and we delist the recently reported record,R.parvulus(Boulenger) from China.Combing with morphological and molecular data,two new species are respectively described from Menghai and Lvchun,Yunnan,China.Raorchestes hillisi sp.nov.is distinguished from all other congeners by the following combination of morphological characters:(1) small body sized(males 15.9-17.7 mm,n=7;female 17.5 mm,n=1);(2) head longer than wide;(3) snout longer than eye diameter;(4) the tip of upper jaws slightly notched;(5) internasal space slightly less than interorbital space;(6) tympanum distinct;(7)fingers lacking lateral dermal fringe;(8) outside of toe Ⅰ and both sides of toe Ⅱ lacking lateral dermal fringe,other toes having weak lateral dermal fringes;(9) rudimentary web on toes;(10) lacking a series of tubercles along the outer sides of forearm and foot;(11) discs of fingers and toes not orange.Raorchestes huanglianshan sp.nov.is distinguished from all other congeners by the following combination of morphological characters:(1) small body size(males 17.0-19.6 mm,n=12;female 21.5 mm,n=1);(2) head slightly wider than long or equal;(3) snout longer than eye diameter;(4)the tip of upper jaws slightly notched;(5) internasal space distinctly less than interorbital space(6) tympanum distinct;(7) fingers lacking lateral dermal fringe;(8) toes lacking lateral dermal fringe;(9) rudimentary web on toes;(10)lacking a series of tubercles along the outer sides of forearm and foot;(11) discs of all fingers and toes orange or parts of them orange in life.Ke JIANG Jinlong REN Jian WANG Junfeng GUO Zeng WANG Yonghong LIU Dechun JIANG Jiatang LI 2020Asian Herpetological Research2020,11,4:1
17Research on the Reconstruction and Renewal of the Landscape Space of Industrial Sites in Post-industrial Era:A Case Study of Guangzhou Zilintang Art Town显示文摘With the rapid development of urbanization,traditional old industrial areas can not cope with the impact of the new wave of urbanization and have been abandoned,demolished and remodeled.Solving the pollution problem of industrial wasteland has become an important part of urban renewal research.Based on the development of industrial sites,the paper discusses the design principles and methods of industrial sites.Through the case analysis of the industrial site of Guangzhou Zilintang Art Town,the paper excavates the deep cultural deposits in the post-industrial era and analyzes the renewal,utilization,transformation and regeneration of the landscape space of industrial sites.GAO Qing ZENG Junfeng 2021Journal of Landscape Research2021,13,3:0
18Switched-capacitor Based Seven-level Boost Inverter with a Reduced Number of Devices显示文摘The conventional multilevel inverters(MLIs)have the disadvantages of numerous devices,incapacity of boost,unbalance for capacitor’s voltage,high complexity for control,and etc.Motivated by this issue,a seven-level boost inverter(7LBI)based on a switched capacitor is presented for singlephase applications in this paper.The proposed 7LBI using only seven transistors can achieve seven output levels,1.5 voltage gain,and natural balance of capacitors’voltages without sensors or other auxiliary methods,which illustrates its suitability for the applications of renewable energy generation.The configuration of topology and operating principles are illustrated in detail.The natural balance of capacitors and capacitance calculations are deduced as well.Moreover,the comparative study is conducted for different types of MLIs.The results illustrate the merits of the proposed 7LBI with respect to reduced devices,lower voltage stress,and less power loss.Finally,a simulation for the proposed 7LBI with PWM modulation is realized based on the theoretical analysis;an experimental prototype is also implemented,verifying multilevel output,boost ability,natural balance for switched capacitors,and performance of transient response.Weijie Lin Jun Zeng Bo Fu Zhixing Yan Junfeng Liu 2024CSEE Journal of Power and Energy Systems2024,10,1:0
19Recent research hotspots in sequencing and the pancreatic neuroendocrine tumor microenvironment显示文摘Multiple endocrine neoplasia 1(MEN1)syndrome,a disease arising from a genetic predisposition to tumor development caused by MEN1 loss-of-function mutations,is characterized by the combined occurrence of neuroendocrine tumors in multiple human organs.With advances in diagnostic technologies and improvements in living standards.Junfeng Xu Wuhu Zhang Xin Lou Zeng Ye Yi Qin Jie Chen Xiaowu Xu Xianjun Yu Shunrong Ji 2023Cancer Biology & Medicine2023,20,10:0
20Interactions between H_(2)O_(2)and dissolved organic matter during granular activated carbon-based residual H_(2)O_(2)quenching from the upstream UV/H_(2)O_(2)process显示文摘Granular activated carbon(GAC)filtration can be employed to synchronously quench residual H_(2)O_(2)from the upstream UV/H_(2)O_(2)process and further degrade dissolved organicmatter(DOM).In this study,rapid small-scale column tests(RSSCTs)were performed to clarify the mechanisms underlying the interactions between H_(2)O_(2)and DOM during the GAC-based H_(2)O_(2)quenching process.It was observed that GAC can catalytically decompose H_(2)O_(2),with a long-lasting high efficiency(>80%for approximately 50,000 empty-bed volumes).DOM inhibited GAC-based H_(2)O_(2)quenching via a pore-blocking effect,especially at high concentrations(10 mg/L),with the adsorbed DOM molecules being oxidized by the continuously generated·OH;this further deteriorated the H_(2)O_(2)quenching efficiency.In batch experiments,H_(2)O_(2)could enhance DOM adsorption by GAC;however,in RSSCTs,it deteriorated DOM removal.This observation could be attributed to the different·OH exposure in these two systems.It was also observed that aging with H_(2)O_(2)and DOM altered the morphology,specific surface area,pore volume,and the surface functional groups of GAC,owing to the oxidation effect of H_(2)O_(2)and·OH on the GAC surface as well as the effect of DOM.Addi-tionally,the changes in the content of persistent free radicals in the GAC samples were insignificant following different aging processes.This work contributes to enhancing understanding regarding the UV/H_(2)O_(2)-GAC filtration scheme,and promoting the application in drinking water treatment.Yaoyao Kang Junfeng Lian Yichun Zhu Zuwen Liu Wentao Li Huiyu Dong Yuanyue Wang Jinfeng Zeng Zhimin Qiang 2023Journal of Environmental Sciences2023,,6:0
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