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64篇 您的检索式:作者名="Heming Li"
    题名 作者 年代 出处 被引量
1Molecular dynamics study on the relationships of modeling,structural and energy properties with sensitivity for RDX-based PBXs显示文摘In this paper,a primary model is established for MD(molecular dynamics) simulation for the PBXs(polymer-bonded explosives) with RDX(cyclotrimethylene trinitramine) as base explosive and PS as polymer binder.A series of results from the MD simulation are compared between two PBX models,which are represented by PBX1 and PBX2,respectively,including one PS molecular chain having 46 repeating units and two PS molecular chains with each having 23 repeating units.It has been found that their structural,interaction energy and mechanical properties are basically consistent between the two models.A systematic MD study for the PBX2 is performed under NPT conditions at five different temperatures,i.e.,195 K,245 K,295 K,345 K,and 395 K.We have found that with the temperature increase,the maximum bond length(L max) of RDX N N trigger bond increases,and the interaction energy(E N-N) between two N atoms of the N-N trigger bond and the cohesive energy density(CED) decrease.These phenomena agree with the experimental fact that the PBX becomes more sensitive as the temperature increases.Therefore,we propose to use the maximum bond length L max of the trigger bond of the easily decomposed and exploded component and the interaction energy E N-N of the two relevant atoms as theoretical criteria to judge or predict the relative degree of heat and impact sensitivity for the energetic composites such as PBXs and solid propellants.XIAO JiJun ZHAO Li ZHU Wei CHEN Jun JI GuangFu ZHAO Feng WU Qiang XIAO HeMing 2012Science China Chemistry2012,55,12:12
2Experimental measurement of the electrical conductivity of single crystal olivine at high temperature and high pressure under different oxygen fugacities显示文摘At 1.0-4.0 GPa and 1123-1473 K and under oxygen fugacity-controlled conditions (Ni + NiO, Fe + Fe3O4, Fe + FeO and Mo+ M0O2 buffers), a YJ-3000t Model six-anvil solid high-pressure apparatus and a Sarltron-1260 Impedance/Gain-Phase analyzer were employed to conduct an in situ measurement of the electrical conductivity of single crystal olivine. Experimental results showed that: (1) within the range of experimentally selected frequencies (103-106 Hz), the electrical conductivity of the sample is of great dependence on the frequency; (2) with the rise of temperature ( T), the electrical conductivity (σ) will increase, and the Arrenhius linear relationship is established between lgσ and 1/T; (3) under the control of oxygen buffer Fe+ Fe3O4, with the rise of pressure, the electrical conductivity tends to decrease whereas the activation enthalpy and independent-of-temperature preexponential factor tend to increase, with the activation energy and activation volume of the sample estimated at (1. 25 ± 0.08) eV and (0.105 ±0.025) cm3/mol, respectively; (4) under given pressure and temperature conditions, the electrical conductivity tends to increase whereas the activation energy tends to decrease with increasing oxygen fugacity; and ( 5) the mechanism of electrical conduction of small polarons can provide insight into the behavior of electrical conduction of olivine under high pressure and high temperature.DAI Lidong LI Heping LIU Congqiang CUI Tongdi SHAN Shuangming YANG Changjun LIU Qingyou DENG Heming 2006Progress in Natural Science:Materials International2006,16,4:9
3Anomaly and geochemistry of rare earth elements and yttrium in the late Permian coal from the Moxinpo mine,Chongqing,southwestern China显示文摘The rare earth elements and yttrium(REY)of the K2 coal from the Moxinpo mine,Chongqing,were determined using inductively coupled plasma mass spectrometry(ICP-MS).The results show that REY are enriched in the K2 coal,with the average content up to 462 lg/g,much higher than average values of most coals in the world.The REY distribution patterns indicate that the light REY is enriched and show a well-pronounced Eu minimum.The fractionation of individual light-REY is higher than that of the heavy-REY.The REY distribution through the K2 coal seam shows that the top and bottom portion of the coal seam have a lower content of REY than the middle portion.Goyazite and rhabdophane were identified with a scanning electron microscope equipped with an energy-dispersed X-ray spectrometer(SEM-EDX).The REY distributions through the coal seam,SEM-EDX data and the correlation analysis between ash yields and the concentrations have revealed that the REY mainly occurs in the organic matter.The K2 coal is a potential rare-metal resource due to its high REY contents,and the coal ash could be regarded as a new and promising raw material for recovery of REY as a by-product.Jianhua Zou Dong Liu Heming Tian Tian Li Feng Liu Lin Tan 2014International Journal of Coal Science & Technology2014,1,1:7
4PDMS microchannel fabrication technique based on microwire-molding显示文摘Micro-flow channel is basic functional component of microfluidic chip,and every step-forward of its construction technique has been receiving concern all over the world.This article presents a not-complicated but flexible method for fabrication of micro-flow channels.This method mainly utilizes the conventional molding capability of polydimethylsiloxane(PDMS) and widespread commercial microwires as templates.We have fabricated out some conventional types of microchannels with different topological shapes,as examples for the demonstration of this flexible fabrication route which was not dependent on the stringent demands of photolithographical or microelectromechanical system(MEMS) techniques.The smooth surface,high-intensity,and high flexibility of the wires made it possible to create many types of topological structures of the two-dimensional or three-dimensional microchannel or channel array.The geometric shape of the cross-section of thus forming microchannel in PDMS was the negative of that of embedded-in microwire,in high-fidelity if suitable measures were taken.More-over,such a microchannel fabrication process can easily integrate the conductivity and low resistivity of the metal wire to create micro-flow devices that are suitable for the electromagnetic control of liquid or the temperature regulation in the microchannel.Furthermore some preliminary optical analysis was provided for the observation of thus forming rounded microchannel.Based on this molding strategy,we even made some prototypes for functional microflow application,such as microsolenoids chip and temperature control gadgets.And an experiment of forming a droplet in the cross channel further confirmed the feasibility and applicability of this flexible microchannel forming technique.JIA YueFei JIANG JiaHuan MA XiaoDong LI Yuan HUANG HeMing CAI KunBao CAI ShaoXi WU YunPeng 2008Chinese Science Bulletin2008,53,24:5
5Preparation,crystal structure and quantum chemical investigation of[Li(NTO) (H_2O)_2]显示文摘[Li(NTO)(H2O2]was prepared by mixing the aqueous solution of 3-nitro-1,2,4-triazol-5-one (NTO) and lithium hydroxide. The crystal structure of [Li(NTO)(H2O)2] was determined by single crystal diffraction analysis. The crystal is monoclinic, space group P21/n with crystal parameters of α =0.7420(2) nm, b=0.344 9(1) nm, c=2.490 6(3) nm,β=94.89(1)°, Z=4, Dc=1.799 g.cm-3, V=0.635 nm3,μ= 1.591 cm-1, F(000) = 392. The final R is 0.051. The MNDO MO calculation shows that the coordinate bonds of title compound possess certain extent of covalent character. O2 atom of NTO anion is bonded to Li atom; the nitro group will be lost first when NTO is decomposed.SONG Jirong , CHEN Zhaoxu , XIAO Heming , HU Rongzu and LI Fuping Department of Chemical Engineering, Northwest University, Xi’ an 710069, China Department of Chemistry, Nanjing University of Science and Technology, Nanjing 210094, China Xi’an Modern Chemistry Research Institute, Xi’ an 710065, China 1999Chinese Science Bulletin1999,44,3:5
6Analysis on Thermal Environment of Underlying Surface and PM2.5 Concentration in Community Park of Beijing in Winter显示文摘Community park is one of the most important landscape spaces for urban people to live outdoors,and people’s perception of environmental microclimate is a direct factor affecting the use frequency and experience of community parks.In this paper,Shijingshan Sculpture Park of Beijing was taken as experimental object.Using the method of fi eld measurement,9-d winter test for 3 months was conducted in three kinds of landscape architecture spaces,including waterfront plaza,open green space and square under the forest.Via regression analysis method,the measured air temperature(Ta),relative humidity of air(RH),particulate matter(PM2.5)were analyzed.It is found that winter sunshine is main infl uence factor of garden microclimate,and there is a negative correlation between local temperature and humidity;local temperature and humidity can regulate the local PM2.5 concentration,and temperature shows negative correlation with PM2.5 concentration,while humidity shows positive correlation with PM2.5 concentration.Meanwhile,via comparative analysis of temperature,humidity and PM2.5 concentration in different types of garden spaces,the infl uence of different space forms,planting forms and materials on thermal environment of underlying surface and PM2.5 concentration was summarized,and design strategy was optimized,to be as benefi cial reference of reconstruction design of community parks.PENG Li XU Zhenghou CHEN Heming 2020Journal of Landscape Research2020,12,6:3
7GENERATOR VIBRATION FAULT DIAGNOSIS METHOD BASED ON ROTOR VIBRATION AND STATOR WINDING PARALLEL BRANCHES CIRCULATING CURRENT CHARACTERISTICS显示文摘Rotor vibration characteristics are first analyzed, which are that the rotor vibration of fundamental frequency will increase due to rotor winding inter-turn short circuit fault, air-gap dynamic eccentricity fault, or imbalance fault, and the vibration of the second frequency will increase when the air-gap static eccentricity fault occurs. Next, the characteristics of the stator winding parallel branches circulating current are analyzed, which are that the second harmonics circulating current will increase when the rotor winding inter-turn short circuit fault occurs, and the fundamental circulating current will increase when the air-gap eccentricity fault occurs, neither being strongly affected by the imbalance fault. Considering the differences of the rotor vibration and circulating current characteristics caused by different rotor faults, a method of generator vibration fault diagnosis, based on rotor vibration and circulating current characteristics, is developed. Finally, the rotor vibration and circulating current of a type SDF-9 generator is measured in the laboratory to verify the theoretical analysis presented above.Wan Shuting Li Heming Li Yonggang Tang Guiji 2005Chinese Journal of Mechanical Engineering2005,18,4:2
8Heterogeneous Microstructure-Induced Mechanical Responses in Various Sub-Zones of EH420 Shipbuilding Steel Welded Joint Under High Heat Input Electro-Gas Welding显示文摘Heterogeneous microstructure-induced mechanical responses in EH420 shipbuilding steel welded joint by electro-gas welding processed have been systematically studied by scanning electron microscopy,electron backscatter diffraction and mechanical testing.Comparing with the coarse-grained heat-affected zone(CGHAZ),the weld metal presents higher toughness(129.3 J vs.37.3 J)as it contains a large number of acicular ferrites with high-angle grain boundaries(frequency 79.2%)and special grain boundary∑3(frequency 55.3%).Moreover,coarse austenite grains in CGHAZ and slender martensite–austenite constituents between bainite laths may likely facilitate crack propagation.Polygonal ferrites and tempered pearlites formed at the junction of the fine-grained heat-affected zone and the intercritical heat-affected zone induced a softened zone with an average hardness of 185 HV0.5,which is the main reason for the occurrence of tensile fracture.Xu Xie Tan Zhao Heming Zhao Song Li Cong Wang 2021Acta Metallurgica Sinica(English Letters)2021,34,10:2
9Preparation of nitrogen doped clews-like carbon materials and their application as the electrode in supercapacitor显示文摘In this work, nitrogen doped clews-like carbon materials were successfully fabricated through hydrothermal polymerization method, followed by post treatment that integrated the carbonization,activation and post-nitrogen doping into one process. This preparation method can form particular hierarchical porous structure without using any sacrificial templates. The experimental results show that the nitrogen doped clews-like hierarchical porous carbon materials possess a relatively high specific surface area of 815 m^2/g with the nitrogen content of 10.58 at%. The electrochemical properties show that the resulting sample delivers 258 F/g at a 0.5 A/g and excellent capacity retention of 79% at 20 A/g. After conducting 10,000 charge-discharge cycles at 10 A/g, the capacitance retention of 98.3% is achieved.These intriguing results demonstrate that the obtained nitrogen doped clews-like carbon materials will be promising electrode materials for supercapacitor and other energy storage devices.Shengrui Chen Jiyuan Liang Jinxing Zhao Haifeng Li Yan Liu Heming Deng Chang Liu Shun Tang Yuan-Cheng Cao 2019Chinese Chemical Letters2019,30,3:2
10Paleogene geological framework and tectonic evolution of the central anticlinal zone in Lufeng 13 sag,Pearl River Mouth Basin显示文摘The Paleogene geological framework and evolution process in the central anticline zone in the Lufeng 13 sag in Pearl River Mouth Basin is well analyzed through seismic data and drilling data,and control of tectonic evolution on hydrocarbon accumulation is also discussed.The results show that the central anticline zone in the Lufeng 13 sag develops the upper deformation layer and lower deformation layer.The“arched graben system”is developed in the upper deformation layer,and the magmatic diapir structure and flowing deformation of plastic strata is developed in the lower deformation layer.The evolution process of the central anticline zone can be divided into four stages,i.e.fault block uplifting stage,prototype stage,strengthening stage and finalization stage.The geological framework and tectonic evolution of the central anticline zone control Paleogene hydrocarbon accumulation.The Paleogene twolayer geological framework is favorable for development of structural traps and composite traps;the paleostructure highs are the direction of hydrocarbon migration,and the gravitational gliding faults are the main carrier bed for vertical hydrocarbon migration;the tectonic uplift is a key factor for reservoir diagenesis improvement and preservation of primary pores,and also controls distribution of high-quality reservoirs.Xudong Wang Xiangtao Zhang Heming Lin Xiaoming Que Yong He Liankai Jia Zhangbo Xiao Min Li 2019Petroleum Research2019,4,3:2
11Construction of [Cu_nI_n]-based coordination polymers via flexible benzimidazolyl-based ligands显示文摘Four new [CunIn]-based coordination polymers, [{Cu4(μ3-I)4(mbbm)2}·2DMF]n (1), [(CuI)2(mbbm)2]n (2), [{Cu2(μ-I)2-(ebbm)2}·2MeCN]n (3), and [Cu2(μ-I)2(prbbm)2]n (4), were prepared from solvothermal reactions of CuI with three flexible ligands [(bzim)(CH2)n(bzim)] (bzim = benzimidazole; n = 1, mbbm; n = 2, ebbm; n = 3, prbbm). These compounds were characterized by elemental analysis, IR and X-ray crystallography. 1 consists of cubanelike [Cu4(μ3-I)4] fragments that link the neighboring ones via mbbm bridges to form a 1D ladder-type chain. 2 contains mononuclear [CuI] fragments that are bridged by mbbm ligands to yield a 1D zigzag chain. 3 or 4 contains a [Cu2(μ-I)2] dimeric fragment, which works as a four-connecting node to link its four equivalent ones to form a 2D (4,4) network (3) or acts as a two-connecting node to connect its two equivalent ones via two pairs of prbbm bridges to form a 1D double chain (4). The photoluminescent properties of 1-4 in the solid state at ambient temperature were investigated.LI LingLing, REN ZhiGang, Lü Xue, WANG HeMing, CHANG YuJie, LI HongXi, WU Bing & LANG JianPing College of Chemistry, Chemical Engineering and Materials Science, Suzhou University, Suzhou 215123, China 2010Science China Chemistry2010,53,10:1
12Determination of surface heat-transfer coefficients of steel cylinder with phase transformation during gas quenching with high per- ssures 显示文摘Cheng Heming Xie Jianbin Li Jianyun 2004Computational Materials Science2004,29,4:1
13Recognition and localization of strawberries from 3D binocular cameras for a strawberry picking robot using coupled YOLO/Mask R-CNN显示文摘To solve the problem of high labour costs in the strawberry picking process,the approach of a strawberry picking robot to identify and find strawberries is suggested in this study.First,1000 images including mature,immature,single,multiple,and occluded strawberries were collected,and a two-stage detection Mask R-CNN instance segmentation network and a one-stage detection YOLOv3 target detection network were used to train a strawberry identification model which classified strawberries into two categories:mature and immature.The accuracy ratings for YOLOv3 and Mask R-CNN were 93.4%and 94.5%,respectively.Second,the ZED stereo camera,triangulation,and a neural network were used to locate the strawberry in three dimensions.YOLOv3 identification accuracy was 3.1 mm,compared to Mask R-CNN of 3.9 mm.The strawberry detection and positioning method proposed in this study may effectively be used to supply the picking robot with a precise location of the ripe strawberry.Heming Hu Yutaka Kaizu Hongduo Zhang Yongwei Xu Kenji Imou Ming Li Jingjing Huang Sihui Dai 2022International Journal of Agricultural and Biological Engineering2022,15,6:1
143D-SoC Analytical Computing and ANSYS Simulation for Thermal Analysis and Design显示文摘LI Wenshi ZHAO Heming LIU Biao 2006Chinese Journal of Electronics2006,15,2:1
15Rho kinase mediates transforming growth factor-β1-induced vasculogenic mimicry formation: involvement of the epithelial-mesenchymal transition and cancer stemness activity显示文摘Vasculogenic mimicry(VM),a newly defined pattern of tumor blood supply,has been identified in several malignant tumors,including hepatocellular carcinoma(HCC).Rho kinase(ROCK)plays an important role in various types of cancers.However,whether ROCK participates in transforming growth factor-β1(TGF-β1)-induced VM formation is unclear.Here,we evaluated the role of ROCK in TGF-β1-induced VM formation in HCC.Our findings showed that the TGF-β1/ROCK signaling pathway is involved in VM formation by inducing the epithelial-mesenchymal transition.Furthermore,TGF-^1 and ROCK were found to play distinct roles in the cancer stem cell phenotype during VM formation.These results provide insights into potential antitumor therapies for inhibiting VM by targeting the TGF-pi/ROCK signaling pathway in HCC.Xue Zhang Jigang Zhang Heming Zhou Gaolin Liu Qin Li 2020Acta Biochimica et Biophysica Sinica2020,52,4:1
16Resveratrol upregulates expression via activation of NF-E2- related factor 2 in PC12 cells 显示文摘Chen CY Jang JH heme oxygenase J Li MH 2005BiochemBiophys Res Commun2005,331,:1
17Determination of surface heat-transfer coefficients of steel cylinder with phase transformation during gas quenching with high pressures显示文摘Cheng Heming Xie Jianbin Li Jianyun 2004Computational Materials Science2004,29,4:1
18Loss-of-function of sox3 causes follicle development retardation and reduces fecundity in zebrafish显示文摘Folliculogenesis is essential for production of female gametes in vertebrates.However,the molecular mechanisms underlying follicle development,particularly apoptosis regulation in ovary,remain elusive.Here,we gen erated sox3 knockout zebrafish lines using CRISPR/Cas9.sox3 knockout led to follicle development retardation and a reduced fecundity in females.Comparative analysis of transcriptome between sox3^-/-and wild-type ovaries revealed that Sox3 was invoIved in pathways of ovarian steroidogenesis and apoptosis.Knockout of sox3 promoted follicle apoptosis and obvious apoptosis signals were detected in somatic cells of stages III and IV follicles of sox3^-/-ovaries.Moreover,Sox3 can bind to and activate the promoter of cyp19a1a.Up-regulation of Cyp19a1a expression promoted 17β-estradiol synthesis,which inhibited apoptosis in follicle development.Thus,Sox3 functions as a regulator of Cyp19a1a expression,via 17β-E2 linking apoptosis suppression,which is implicated in improving female fecundity.Qiang Hong Cong Li Ruhong Ying Heming Lin Jingqiu Li Yu Zhao Hanhua Cheng Rongjia Zhou 2019Protein & Cell2019,10,5:1
19Theoretical and experimental studies of structure and inhibition efficiency of imidazoline derivatives显示文摘Daxi Wang Shuyuan Li Yu Ying Mingjun Wang Heming Xiao Zhaoxu Chen 1999Corrosion Science1999,,10:1
20Theoretical and experimental studies of structure and inhibition efficiency of imidazoline derivatives显示文摘Daxi Wang Shuyuan Li Yu Ying Mingjun Wang Heming Xiao Zhaoxu Chen 1999Corrosion Science1999,,10:1
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