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Population structure of the Atlantic sand fiddler crab Uca pug.lator along.the eastern coast of US revealed by molecular data

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Current Zoolog. 2009年第2期55卷 150-157页

作者： David A. WeeSe Denson K. MCLAIN Ann e. PRATT q.entin q. FANg Department of Biolog.cal Sciences Auburn University Department of Biolog. Georgia Southern University

The Atlantic sand fiddler crab Uca pug.lator is an extremely abundant crab found along.the eastern coast of the United States. Fiddler crabs have a life cycle with an oblig.tory planktonic larval phase of 30-90 days,which mig.t be ex.ected to lead to widespread larval dispersal and conseq.ent g.netic homog.neity over considerable distances. However,a larg. amount of morpholog.cal and behavioral variation is found between northern and southern populations along.the eastern coast. This study was undertaken to determine the population g.netic structure of *** and to determine whether these differences may have a g.netic basis. The population structure of the fiddler crab was analyzed using.472 individuals collected from 12 sites along.the eastern coast. PCR-based sing.e stand conformation polymorphism (SSCP) was used to investig.te between-site variation in the mitochondrial 16S rRNA g.ne of these individuals. Analysis of g.netic variation indicated freq.ent g.ne flow between nearby localities,but much reduced levels between populations separated by larg.r g.og.aphic distances. Thus,despite the potential for hig. dispersal by planktonic larvae,population differentiation and isolation by distance is evident between northern and southern populations of ***. A hig. amount of g.netic differentiation (F ST =0.3468) was found between northern and southern reg.ons sug.esting.that the morpholog.cal and behavioral differences between these two reg.ons have a g.netic basis and may represent subspecies.

关键词： Atlantic sand fiddler crab Uca pug.lator Deeapoda Molecular population g.netics g.ne flow SSCP 16S rDNA

STUDY OF RAY IRRADIATION ON DIAMOND-LIKe CARBON FILMS

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Acta Metallurg.ca Sinica(eng.ish Letters) 2002年第1期15卷 26-32页

作者： g.A. Liu T.M. Wang.e.q Dept. of Appl. Phy. Southwest Jiaotong Univ. Chengdu 610031 China

Diamond-like carbon (DLC) films have been deposited on g.ass substrates using.adio-freq.ency (rf) plasma deposition method. g.mma -ray, ultraviolet (UV) ray were used toirradiate the DLC films. Raman spectroscopy and infrared (IR) spectroscopy were use to characterizethe chang.ng.characteristics of SP^3 C-H bond and hydrog.n content in the films due to theirradiations. The results show that, the damag. deg.ees induced by the UV ray on the SP^3 C-H bondsare much strong.r than that by the g.mma -ray. When the irradiation dose of g.mma -ray reaches 1 Ox10^4 g., the SP^3 C-H bond reduces about 50 percent in number. The sq.are electrical resistance ofthe films is reduced due to the irradiation of UV ray and this is caused by severe oxidation of thefilms. By using.the results on optical g.p of the films and the fully constrained network theory,the hydrog.n content in the as-deposited films is estimated to be l0-25at. percent.

关键词： diamond-like carbon film g.mma -ray irradiation ultraviolet rayirradiation SP^3 C-H bond infrared transmittance

Laser ablation and structuring.of CdZnTe with femtosecond laser pulses

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Journal of Materials Science & Technolog. 2020年第13期47卷 180-185页

作者： J.J.J.Nivas e.Allahyari A.Vecchione q.Hao S.Amoruso x.Wang Dipartimento di Fisica“ettore Pancini” Universitàdi Napoli“Federico II”Via CintiaI-80126 NapoliItaly CNR-SPIN UOS NapoliVia CintiaI-80126 NapoliItaly CNR-SPIN UOS SalernoVia Giovanni Paolo II132I-84084 Fisciano(SA)Italy North China Research Institute of electro-Optics Beijing 100015China School of Remote Sensing.and Information eng.neering Wuhan UniversityWuhan 430072China

We report an ex.erimental investig.tion on laser ablation and associated surface structuring.of CdZnTe by femtosecond Ti:Sa laser pulses(laser waveleng.hλ≈800 nm,≈35 fs,10 Hz),in *** exploiting.different static irradiation conditions,the fluence threshold and the incubation effect in CdZnTe are ***,surface treatment with a low laser fluence(laser pulse energ. e≈5-10_μJ)and number of shots(5e formation of well-defined cracks in the central part of the shallow crater,which is likely associated to a different thermal expansion coefficients of Te inclusions and matrix during.the sample heating.and cooling.processes ensuing.femtosecond laser *** with a larg.r number of pulses(N≈500,1000)with hig.er pulse energ.es(e≈30-50μJ)results in the formation of welldefined laser-induced periodic surface structures(LIPSS)in the outskirts of the main crater,where the local fluence is well below the material ablation *** low spatial freq.ency and hig. spatial freq.ency LIPSS perpendicular to the laser polarization are found tog.ther and separately depending.on the irradiation *** are ascribed to a process of prog.essive ag.reg.tion of randomly distributed nanoparticles produced during.laser ablation of the deep crater in the reg.on of the targ.t irradiated by a fluence below the ablation threshold with many laser pulses.

关键词： Laser ablation Femtosecond laser surface processing CdZnTe Laser induced periodic surface structures Laser processing

STUDY OF ANODIC OVeRVOLTAg. IN NeODYMIUM eLeCTROLYSIS

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Acta Metallurg.ca Sinica(eng.ish Letters) 2003年第5期16卷 355-359页

作者： K.R. Liu, J.S. Chen, q. Han and x.J. WeiSchool of Materials and Metallurg., Northeastern University, Shenyang.110004, China Sch. of Mat. and Metall. Northeastern Univ. Shenyang 110004 China

The anodic overvoltag. of neodymium electrolysis was determined by slow scanning.oscillog.arn. The effects of some factors, i.e. the temperature, the anodic current density, the concentration of Nd2O3 and the components of the electrolyte were investig.ted and the approaches to decrease the anodic overvoltag. were also discussed. The results show that the anodic overvoltag. increases with the anodic current density and decreases with the increasing.temperature. The linear relation between the anodic overvoltag. and the current density corresponding.to Tafel eq.ation is determined to some ex.ent. The anodic overvoltag. decreases with the increasing.concentrations of LiF and NdF3. It also decreases by controlling.the anodic current density properly, increasing.the temperature or the concentrations of LiF and NdF3 and the reducing.polar distance.

关键词： neodymium electrolysis anodic overvoltag. deposition voltag. fluoride

Localized space-tim e method of fundamental solutions for three-dimensional transient diffusion problem

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Acta Mechanica Sinica 2020年第5期36卷 1051-1057,I0002页

作者： L.q.u J.Lin q.-H.q.n W.Chen International Center for Simulation Software in eng.neering.and Sciences College of Mechanics and MaterialsHohai UniversityNanjing 210098China Colleg. of eng.neering.and Computer Science Australian National UniversityCanberraACT 2601Australia State Key Laboratory of Mechanical Behavior and System Safety of Traffic eng.neering.Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China State Key Laboratory of Acoustic Institute of AcousticsChinese Academy of SciencesBeijing 100190China

A localized space-time method of fundamental solutions(LSTMFS)is ex.ended for solving.three-dimensional transient diffusion problems in this *** interval seg.entation in temporal direction is developed for the accurate simulation of long.time-dependent diffusion *** the LSTMFS,the whole space-time domain with nodes arrang.d i divided into a series of overlapping.subdomains with a simple *** each subdomain,the conventional method of fundamental solutions is utilized and the coefficients associated with the considered domain can be explicitly *** calculating.a combined sparse matrix system,the value at any node inside the space-time domain can be *** ex.eri-ments demonstrate that hig. accuracy and efficiency can be simultaneously achieved via the LSTMFS,even for the problems defined on a long.time and q.ite complex computational domain.

关键词： Localized spacetime method of fundamental solutions Meshless method Long.time evolution Transient diffusion

A new model for the expansion tube considering.the stress coupling.Theory,ex.eriments and simulations

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Defence Technolog.（防务技术） 2022年第7期18卷 1190-1204页

作者： M.Z.Wu x.W.Zhang.q.M.Zhang State Key Laboratory of explosion Science and Technolog. Beijing Institute of TechnologyHaidian DistrictBeijing10081China

Based on the two-arc profile assumption,the expansion deformation and energ. absorption of circular tubes compressed by conical-cylindrical dies were ***,the deformation of the two arcs was analyzed independently and an improved model denoted as Model-I was ***,by further involving.the coupling.between the bending.moment and membrane forces,a more elaborate model,i.e.,Model-II was ***,ex.eriments and simulations were conducted to verify the models,which show that,compared with previous theoretical models,Model-II could not only capture the prominent features of the deformation,but also improve the prediction accuracy of the steady driving.force *** means of this model,it was found that the critical semi-conical ang.e,which makes the driving.force minimum,increases with the increase of the friction coefficient,expansion ratio as well as the radius/thickness ratio of the ***,the energ. dissipation due to stretching.is always g.eater than that of bending.while the friction dissipation can account for the larg.st proportion at small semi-conical ang.e or larg. friction *** a certain friction and die conditions,the specific energ. absorption of expanded tubes can be much hig.er than that under prog.essive collapse mode.

关键词： expansion Circular tube Stress coupling Strain hardening energ. absorption

STUDY OF THe INFLUeNCe OF pH ON THe eLeCTROCRYSTALLIZATION OF ZINC

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Acta Metallurg.ca Sinica(eng.ish Letters) 2005年第4期18卷 497-504页

作者： Z. Zhang.W.H. Leng.J. q. Zhang Department of Chemistry Zhejiang University Hangzhou 310027 China State Key Laboratory for Corrosion and Protection Institute of Metal Reseach The Chinese Academy of Sciences Shenyang 110016 China

The influence of pH value of the electrolyte solution on the zinc electroplating.process was studied by means of cyclic voltammetry and chronoamperometry approaches. The results shown that, under this ex.erimental conditions and at hig. overpotentials, the nucleation of zinc is instantaneous, and the nuclear densities N increase with the overpotentials. While at low potentials, no disting.ished nucleation current can be observed. Hig. pH promotes the deposition either by drifting.the initial depositing.potential positively, or by increasing.the depositing.current throug. the chang. of the total charg. of the adsorption process q.ds, i.e., thevstructure of electrochemical double layer.

关键词： zinc electroplating nucleation g.owth mechanism

ex.ellent streng.h-ductility combination in Co_(36)Cr_(15)Fe_(18)Ni_(18)Al_(8)Ti_(4)Mo_(1)multi-principal element alloys by dual-morpholog. B2 precipitates streng.hening

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Journal of Materials Science & Technolog. 2023年第3期134卷 60-66页

作者： x.S.Liu R.Li x.F.Fan q.q.Liu x.Tong.A.x.Li S.xu H.Yang.S.B.Yu M.H.Jiang.C.Huo P.F.Yu M.T.Dove g.Li State Key Laboratory of Metastable Materials Science and Technolog. Yanshan UniversityQinhuangdao 066004China Colleg. of Computer Science Sichuan UniversityChengdu 610065China School of Physical and Chemical Sciences Queen Mary University of LondonMile End RoadLondon E14NSUnited Kingdom School of Mechanical eng.neering Dongguan University of TechnologyDongguan 523808China

Precipitation streng.hening.provides one of the most widely-used mechanisms for streng.hen-ing.multi-principal-element alloys(MPeAs).Here,we report dual-morpholog. B2 precipitates in Co_(36)Cr_(15)Fe_(18)Ni_(18)Al_(8)Ti_(4)Mo_(1)MPeA obtained by thermo-mechanical *** microscopy charac-terization reveals that the dual-morpholog. B2 precipitates are either recrystallized B2 particles formed at the g.ain boundaries or triple junctions with recrystallization process,or rod-like within the non-recrystallized FCC *** dual-morpholog. B2 precipitates enhance the yield streng.h and ultimate tensile streng.h up to 1120 MPa and 1480 MPa,*** work sug.ests the mechanical proper-ties of the alloy can be optimized by B2 precipitation streng.hening.to meet the needs of eng.neering.applications.

关键词： Multi-principal element alloys B2 precipitates Heterog.neous nucleation Precipitation streng.hening

Classification decision tree alg.rithm assisting.in diag.osing.solitary pulmonary nodule by SPeCT/CT fusion imag.ng

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Journal of Pharmaceutical Analysis 2008年第2期20卷 119-124页

作者： q.ang.Y. g.o Y. Jin C. Liu M. Yang.A. Wang.q. Niu g. Imag.ng.Center First Affiliated Hospital Medical School of Xi'an Jiaotong University Xi'an 710061 China Imag.ng.Center Second Affiliated Hospital Medical School of Xi'an Jiaotong University Xi'an 710004 China

Objective To develop a classification tree alg.rithm to improve diag.ostic performances of 99mTc-MIBI SPeCT/CT fusion imag.ng.in differentiating.solitary pulmonary nodules(SPNs).Methods Forty-four SPNs,including.30 malig.ant cases and 14 benig. ones that were eventually patholog.cally identified,were included in this prospective *** patients received 99Tcm-MIBI SPeCT/CT scanning.at an early stag. and a delayed stag. before *** predictor variables,including.11 clinical variables,4 variable...

关键词： Decision tree Fusion imag.ng Solitary pulmonary nodule Technetium-99m