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Acta Mechanica Sinica 2020年第6期36卷 1294-1301,I0003页

作者： C.G.Chai A.G.Pi q.M.Li F.L.huang Institute of Chemical Materials China Academy of Engineering PhysicsMianyang621900China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China School of Mechanical Aerospace and Civil EngineeringUniversity of ManchesterManchesterM139PLUK

Similarity can reflect common laws in the mechanism of rigid-body *** this paper,the similarities in rigid-body penetration depth are demonstrated by three non-dimensional but physically meaningful quantities,i.e.,ρkinetic,I∗ln and N′*** three quantities represent the non-dimensional areal density of projectile kinetic energy,the effect of nose geometry,and the friction at the interactive cross section between projectile and target *** is shown that experimental data of rigid projectile penetration,from shallow to deep penetration,can be uniquely unified by these three similarity quantities and their ***,for ogival nose projectiles,their penetration capacities are dominated byρkinetic,which is consisted by non-dimensional effective length Leff and non-dimensional quantity Dpn=ρpv20Ay which has the same form as Johnson’s damage *** the sacrifice of minor theoretical accuracy,the non-dimensional penetration depth P/d can be understood as directly controlled by Dpn,enhanced by projectile effective length Leff under a multiplication relation,and optimized by projectile nose geometry in the formation of I∗ln.

关键词： Concrete target Deep penetration Similarity-Johnson's damage number

Experimental study of“Tong Xia”purgative method in ameliorating lung injury in acute necrotizing pancreatitis

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World Journal of Gastroenterology 2000年第1期6卷 115-118页

作者： Xia q Jiang JM Gong X Chen Gy Li L huang ZW Department of TCM The First University Hospital of West China University of Medical SciencesChengdu 610041Sichuan ProvinceChina.

AIM To investigate the role of tumor necrosisfactor(TNF)in lung injury during acutenecrotizing pancreatitis(ANP),and thetherapeutic effect of'Tong Xia'purgativemethod in minimizing the severity of lung *** Fourteen canines were randomlydivided into 3 groups:the'Tong Xia'treatmentgroup(n = 5)using Dachengqitang;salinecontrol group(n = 5),and the sham operationgroup(n = 4).TNF activity in serum and inbronchoalveolar lavage fluid(BALF),the serumendotoxin levels were measured,and theseverity of lung injury *** Elevation of TNF activity was moreprominent in BALF than in *** activity inserum at 6 and 12 hours and in BALI:wassignificantly decreased in the'Tong Xia'treatment group than in the saline control one(q=21.11,q=12.07,q=9.03,respectively,Py was significantlyalleviated at 12 hours as compared with that inthe saline group,manifested as amelioration otthe lung wet/ dry weight ratio,decrease inprotein concentration and neutrophils count inBALF,and improvement of pulmonaryinflammatory changes.A positive correlationwas demonstrated between serum TNF activity and endotoxin *** Hypersecretion of TNF is shownto be one of the major causes of lung injuryduring ANP;'Tong Xia'purgative method couldalleviate the degree of lung injury mediated byTNF.

关键词： Subject headings pancreatitis/therapy lung disease tumor necrosis factor Tong Xia method

Hot Deformation Behavior and Processing Maps of a High Al-low Si Transformation-Induced Plasticity Steel: Microstructural Evolution and Flow Stress Behavior

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Acta Metallurgica Sinica(English Letters) 2018年第5期31卷 503-514页

作者： H.q.huang H.S.Di N.yan J.C.Zhang y.G.Deng R.D.K.Misra J.P.Li State Key Laboratory of Rolling and Automation Northeastern University Laboratory for Excellence in Advanced Steel Research Department of Metallurgical Materials and Biomedical Engineering University of Texas at El Paso

Hot deformation behavior of a high Al-low Si transformation-induced plasticity（TRIP） steel was studied by an MMS-300 thermo-simulation machine at the temperature range of 1050–1200℃ and strain rate range of 0.01–10s^（-1）. The constitutive equations of the TRIP steel were established at high temperature by fitting the strain factor with a sixth-order polynomial. The instability during hot rolling was discussed using processing maps. The results reveal that two types of flow stress curves（dynamic recrystallization and dynamic recovery） were observed during the hot compression of the high Al-low Si TRIP steel. Flow stress decreased with increasing deformation temperature and decreasing strain rate. The predicted flow stress of experimental TRIP steel is in agreement with the experimental values with an average absolute relative error of 4.49% and a coefficient of determination of 0.9952. According to the obtained processing maps, the TRIP steel exhibits a better workability at strain rate of 0.1s^（-1） and deformation temperature of 1200℃ as compared to other deformation conditions.

关键词： TRIP steel Hot compression Constitutive equation Processing maps

Effect of catheter radiofrequency ablation on C-reactive protein, brain natriuretic peptide and echocardiograph in patients with persistent and permanent atrial fibrillation

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Chinese Medical Journal 2014年第4期127卷 623-626页

作者： huang q qiuCG yuan yq Zhao y J Mao yL Wang RM Wang q Department of Cardiology First Affiliated Hospital of Zhengzhou University Zhengzhou Henan 450052 China Department of Cardiology Zhengzhou Cardiovascular Hospital Zhengzhou Henan 450016 China

Background Radiofrequency catheter ablation （RFCA） for atrial fibrillation （AF） has developed rapidly,and is a commonly performed ablation in many major hospitals throughout the world,due to its satisfactory *** aim of this study was to detect the effect of RFCA on C-reactive protein （CRP）,brain natriuretic peptide （BNP）,and echocardiograph in patients with persistent and permanent *** A total of 120 patients （71 males,mean age （50.8＆#177;12.0） years） with persistent and permanent AF undergoing RFCA under guidance of the Carto merge technique were *** atrial diameter （LAD）,right atrial diameter （RAD）,left ventricular ejection fraction （LVEF）,CRP,and BNP were observed 3,6 and 12 months after RFCA and compared with results before *** recurrence of atrial arrhythmias was observed 3 and 12 months after the *** Compared with that before RFCA,LAD and RAD decreased and LVEF increased significantly after ***,the levels of CRP and BNP were reduced significantly at 3,6,and 12 months after RFCA （P〈0.05）.In the non-recurrent patients,LVEF was increased significantly compared with the recurrent patients at 3,6,and 12 months after RFCA （P〈0.05）.CRP and BNP levels were decreased significantly in the non-recurrent patients compared with the recurrent patients at 3,6,and 12 months after RFCA （P〈0.05）.After one or two applications of RFCA,during a follow-up of 12 months,12 patients （10.0%） had AF,10 patients （8.3%） had atrial flutter,and 5 patients had atrial tachycardia （4.2%）.Conclusions Conversion of AF to sinus rhythm by RFCA,has been shown to reduce LA size and improve *** can also significantly decrease the levels of CRP and BNP in patients with persistent and permanent AF and reduce the risk of inflammation and developing heart failure.

关键词： atrial fibrillation catheter ablation C-reactive protein brain natriuretic peptide morphology

Hardening and toughening effects of intermediate nanosized structures in a confined amorphous alloy film

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Journal of Materials Science & Technology 2022年第23期118卷 44-53页

作者： Z.q.Chen M.C.Li X.Tong y.Zhao J.y.Xie S.W.Guo P.huang F.Wang H.B.Ke B.A.Sun W.H.Wang Songshan Lake Materials Laboratory Dongguan 523808China Institute of Physics Chinese Academy of SciencesBeijing 100190China Xinjiang Key Laboratory of Solid State Physics and Devices and School of Physical Science and Technology Xinjiang UniversityXinjiangUrumqi 830046China Key Laboratory of LCR Materials and Devices of yunnan Province School of Materials and EnergyYunnan UniversityKunming 650091China State-Key Laboratory for Mechanical Behavior of Material Xi’an Jiaotong UniversityXi’an 710049China State Key Laboratory for Strength and Vibration of Mechanical Structures Xi’an Jiaotong UniversityXi’an 710049China National Demonstration Center for Experimental Mechanics Education Xi’an Jiaotong UniversityXi’an 710049China

The plastic deformation of amorphous alloys is well known to be localized into shear bands(SBs),which are believed to stem from the atomic-scale flow defects,i.e.,shear transformation zones(STZs).yet,the bridge between the mesoscopic SBs and the atomic-scale STZs remains poorly *** this work,through thermally activating pronouncedβrelaxations in the well-designed crystalline-layer confined amorphous(CLCA)Ni W alloy films,we experimentally captured and observed an intermediate nanosized structure termed as“nano shear bands”(NSBs)with a typical size of 1–2 nm in thickness and5–10 nm in *** influences of such NSB structures on the macroscale deformation behavior were systematically *** was found that NSBs lead to both hardening and toughening effects for the CLCA films,as they promote multiple and controlled shear banding deformation,which results in enhanced *** intermediate NSB structure could connect the microstructural characteristics and macroscopic plasticity in amorphous alloys and may provide new insights for understanding the microscopic deformation mechanism of amorphous alloys as well as tuning/designing their properties.

关键词： Amorphous alloys Nano shear band Hardening Toughening Crystallization

PERSPECTIVES IN MECHANICS OF HETEROGENEOUS SOLIDS

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Acta Mechanica Solida Sinica 2011年第1期24卷 1-26页

作者： C.q. Chen J.Z. Cui H.L. Duan X.q. Feng L.H. He G.K. Hu M.J. huang y.Z. Huo B.H. Ji B. Liu X.H. Peng H.J. Shi q.P. Sun J.X. Wang y.S. Wang H.P. Zhao y.P. Zhao q.S. Zheng W.N. Zou Department of Engineering Mechanics AML Tsinghua University Beijing 100084 China Academy of Mathematics and Systems Sciences Chinese Academy of Sciences Beijing 100190 China State Key Laboratory for Turbulence and Complex System and Department of Mechanics and Aerospace Engineering College of Engineering Peking University Beijing 100871 China CAS Key Laboratory of Mechanical Behavior and Design of Materials University of Science and Technology of China Hefei Anhui 230026 China School of Aerospace Engineering Beijing Institute of Technology Beijing 100081 China Institute for Advanced Study Nanchang University Nanchang 330031 China Depariment of Mechanics and Engineering Sciences Fudan University 220 Handa Road Shanghai 200433 China Department of Mechanical Engineering Hong Kong University of Science and Technology Hong KongChina Department of Mechanical Engineering Hong Kong University of Science and Technology Hong Kong China Institute of Engineering Mechanics Beijing Jiaotong University Beijing 100044 China State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China

The Micro- and Nano-mechanics Working Group of the Chinese Society of Theoretical and Applied Mechanics organized a forum to discuss the perspectives, trends, and directions in mechanics of heterogeneous materials in January 2010. The international journal, Acta Mechanica Solida Sinica, is de- voted to all fields of solid mechanics and relevant disciplines in science, technology, and engineering, with a balanced coverage on analytical, experimental, numerical and applied investigations. On the occasion of the 30TM anniversary of Acta Mechanica Solida Sinica, its editor-in-chief, Professor q.S. Zheng invited some of the forum participants to review the state-of-the-art of mechanics of heterogeneous solids, with a particular emphasis on the recent research development results of Chinese scientists. Their reviews are organized into five research areas as reported in different sections of this paper. ~I firstly brings in fo- cus on micro- and nano-mechanics, with regards to several selective topics, including multiscale coupled models and computational methods, nanocrystal superlattices, surface effects, micromechanical damage mechanics, and microstructural evolution of metals and shape memory alloys. ~II shows discussions on multifield coupled mechanical phenomena, e.g., multi-fields actuations of liquid crystal polymer networks, mechanical behavior of materials under radiations, and micromechanics of heterogeneous materials. In ~III, we mainly address the multiscale mechanics of biological nanocomposites, biological adhesive surface mechanics, wetting and dewetting phenomena on microstructured solid surfaces. The phononic crystals and manipulation of elastic waves were elaborated in ~IV. Finally, we conclude with a series of perspectives on solid mechanics. This review will set a primary goal of future science research and engineering application on solid mechanics with the effort of social and economic development.

关键词： heterogeneous materials smart materials biological materials multiscale mechanics micro- and nano-mechanics damage and fracture constitutive relation elastic wave surface effects

High strength Al-Cu-Mg based alloy with synchronous improved tensile properties and hot-cracking resistance suitable for laser powder b e d fusion

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Journal of Materials Science & Technology 2023年第10期141卷 155-170页

作者： q.Z.Wang N.Kang X.Lin M.EL Mansori W.D.huang State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Arts et Metiers Institute of Technology MSMPHESAM UniversitéChâlons-en-Champagne F-51006France Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design MIIT ChinaNorthwestern Polytechnical UniversityXi’an 710072China Texas A&M Engineering Experiment Station Institute for Manufacturing SystemsCollege StationTX 77843USA

In present work,a novel crack-free Al-Cu-Mg-Si-Ti alloy with synchronous improved tensile properties and hot-cracking resistance was proposed and successfully manufactured by laser powder bed fusion(LPBF).The microstructure evolution behaviors and the corresponding strengthening mechanisms were investigated in *** LPBF-processed Al-Cu-Mg-Si-Ti alloy presents a heterogeneous microstructure consisting of ultrafine equiaxed grains(UFGs)at the boundary and coarse columnar grains(CGs)at the center of the single molten ***-precipitated D022-Al 3 Ti particles were found to act as the nuclei to refine the grains at the boundary of the molten pool during solidification process,which is attributed to the low cooling rate providing the sufficient incubation time for the precipitation of D022-Al 3 *** are two orientation relationships(ORs)betweenα-Al and D022-Al 3 Ti,i.e.[001]α-Al//[001]D022-Al3Ti,(200)α-Al//(200)D022-Al3Ti and[1¯1¯2]α-Al//[¯111]D022-Al3Ti,(1¯11)α-Al//(¯11¯2)D022-Al3Ti,which are two of the eight ORs predicted with the E2EM *** grains in present alloy,no matter for UFGs or CG,exhibited high critical hot-cracking stress,which means a strong hot-cracking ***-nanoprecipitation of Cu-,Mg-,and Si-rich q’and S’phases was introduced to enhance the mechanical performance ofα-Al *** as-built sample exhibits superior tensile properties,with the yield strength(yS)of 473±8 MPa,ultimate tensile strength(UTS)of 541±2 MPa and elongation(EI)of 10.9%±1.2%.

关键词： Laser powder bed fusion High strength Al-Cu-Mg alloys Duplex microstructure Precipitation Tensile properties

Using SPOT 5 fusion-ready imagery to detect Chinese tamarisk(saltcedar)with mathematical morphological method

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International Journal of Digital Earth 2014年第3期7卷 217-228页

作者： q.S.Liu G.H.Liu C.huang C.J.Xie State Key Laboratory of Resources and Environmental Information System Institute of Geographic Science and Natural Resources ResearchChinese Academy of SciencesBeijingChina

Chinese tamarisk(saltcedar)is a deciduous shrub that occurs widely across the yellow River Delta in *** spatial structure of Chinese tamarisk is believed to have an influence on the landscape and habitats of rare *** this study,first,Chinese tamarisk is detected using Canny edge detector and mathematical morphological operators based on SPOT 5 fusion-ready *** the numbers,areas,locations,and patch spacing of Chinese tamarisk patches are *** experiments show that the detection accuracy of Chinese tamarisk patches is about 93.4%after the disconnection of connected *** distribution orientation of about 70%of the patches is approximately *** 91%of the minimum distances among the patches are between 12.5 and 57.5 *** rose graph indicates that the main azimuth between patches is north--northwest,and the second is northeast and *** present study indicates that the integrating Canny edge detector with the algorithms for extracting circular and elliptical objects based on mathematical morphology is simple and effective for detecting Chinese tamarisk patches and is easy to identify the spatial structure of Chinese tamarisk patches,which reduces the time and labor for the visual interpretation of Chinese tamarisk patches.

关键词： SPOT 5 Chinese tamarisk spatial structure mathematical morphology patch

PHySICAL SIMULATION OF CONTINUOUS ROLL CASTING PROCESS

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Acta Metallurgica Sinica(English Letters) 2005年第4期18卷 505-511页

作者： L.H. Zhan J. Zhong X.q. Li M.H. huang College of Electronical-Mechanical Engineering Central South University Changsha 410083China

A series of simulating experimental studies on the rheological behavior and its influential factors of aluminum alloy in continuous roll-casting process have been explored in this paper with a Gleeble-1500 Thermal-Mechanical Simulation Tester and a set of special clamp system. Relevant rheological rules in the process of coupling transient solidification and continuous deformation of roll-casting conditions are obtained. Experimental results indicate that four different characteristic stages exist in the whole rheological process, and relative constitutive models suitable for the given conditions of continuous roll casting process have been established through multivariable linear regression analysis of the experimental data.

关键词： continuous roll-casting rheological behavior physical simulation,constitutive relation