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Acoustic Measurements for Determination of th. Materials Damping using A Sound Source Localisation System

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Acta Metallurgica Sinica(English.Letters) 2013年第2期26卷 113-121页

作者： J. Gken J. Swiostek h. h.rdelbrink u. Keil Faculty of Maritime Studies University of Applied Sciences Emden/Leer Bergmannstr. 36 26789 LeerGermany Stalomax TM Company of High-Precision Mechanics ul. Parkingowa 45 37450 Stalowa WolaPoland

Noise measurements are especially a problem wh.n th. object under investigation is largely dimensioned and can only be measured from th. distance. To obtain information about th. location of noise generation, a measurement tech.ique wh.ch.makes sound visible in order to introduce furth.r specific tech.ical measures is advantageous. Th. question is if th. time dependence of th. signal got from such.a non touch.ng and non destructive acoustic meth.d h.s th. potential to calculate th. materials damping from. using a small sound source localization system （Microflown^TM probe）, specimens of magnesium alloys with.different grain sizes obtained by h.drostatic extrusion were investigated. It h.s been demonstrated th.t th. fine grained microstructure led to a lower damping and its dependence on th. strain was reduced. In th.s context, acoustic measurements by a sound source localisation system wh.ch.makes materials ch.racterization possible could be used as a quality tool to detect ch.nges in h.gh.y stressed components. Th.s approach.allows to promote a selective substitution of conventional materials by more innovative ones. Th. offsh.re sector is considered to be a field of application： Wind turbines produce noise emission wh.ch.stems mainly from turbulences at th. tips of th. rotor blades and vibrations of components inside th. nacelle （e.9. gearbox, generator, ...）. If th. vibration amplitudes are too h.gh. microcracks of components can lead to failure over th. long term. Th. monitoring of microstructural ch.nges using a larger type of a sound source localisation system is considered as an innovative tech.ical approach.with.respect to maintenance activities.

关键词： Magnesium Noise measurements MicroflownTM Damping

Asymmetric Magnetization Reversal Probed by Recoil Loop Measurements in an Exch.nge Biased La0.67Sr0.33MnO3/La0.33Ca0.67MnO3 Bilayer Film

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Ch.nese Ph.sics Letters 2008年第1期25卷 278-281页

作者：王志宏 h.-u.h.BERMEIER G.CRISTIANI 孙继荣沈保根 State Key Laboratory of Magnetism Institute of Physics Chinese Academy of Sciences PO Box 603 Beijing 100080 Max-Planck-Institut fur Festkoperforsch.ng Heisenbergstrasse 1 D-70569 Stuttgart Germany

We exploit th. recoil loop measurements to study La0.07 Sr0.33 Mn O3/La0.33 Ca0.67 Mn O3 bilayer film. th. asymmetric magnetization reversal in an exch.nge-biased It is found th.t th. recoil curve encloses a marked area only in th. second quadrant of th. h.steresis loop, and th. recoil susceptibility in th. descending branch.of th. major loop is evidently h.gh.r th.n th.t in th. ascending branch. Th. study indicates th.t th. exch.nge anisotropy of a unidirectional nature and an orientation deviated from th. easy axis of th. ferromagnetic layer plays a crucial role in creating th. reversal asymmetry.

关键词： h.STERESIS LOOPS ANISOTROPY MAGNETS

Th. spin-isospin decomposition of th. nuclear symmetry energy from low to h.gh.density

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Ch.nese Ph.sics C 2020年第5期44卷 114-118页

作者： Wenmei Guo M.Colonna V.Greco u.Lombardo h.-JSch.lze Department of Ph.sics Anhui Normal UniversityWuhu 241000China Laboratori Nazionali del Sud(INFN) Via S.Sofia 6295123 CataniaItaly Dipartimento di Fisica e Astronomia Via S.Sofia 6495123 CataniaItaly INFN Sezione di CataniaVia S.Sofia 6295123 CataniaItaly

Th. energy per particle BA in nuclear matter is calculated up to h.gh.baryon density in th. wh.le isospin asymmetry range from symmetric matter to pure neutron *** results,obtained in th. framework of th. Brueckner-h.rtree-Fock approximation with.two-and th.ee-body forces,confirm th. well-known parabolic dependence on th. asymmetry parameterβ=(N?Z)/A(β^2 law)th.t is valid in a wide density *** investigate th. extent to wh.ch.th.s beh.vior can be traced back to th. properties of th. underlying interaction,aside from th. mean field approximation,th. spin-isospin decomposition of BA is *** indications suggest th.t th.β^2 law could be violated at h.gh.r densities as a consequence of th. th.ee-body *** raises th. problem th.t th. symmetry energy,calculated according to th.β^2 law as a difference between BA in pure neutron matter and symmetric nuclear matter,cannot be applied to neutron *** sh.uld return to th. proper definition of th. nuclear symmetry energy as a response of th. nuclear system to small isospin imbalance from th. Z=N nuclei and pure neutron matter.

关键词： symmetry energy nuclear interaction spin-isospin decomposition nuclear matter

A Population Balance Model for Disperse Systems:Particle Size Distribution in Suspension Polymerization

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Ch.nese Journal of Ch.mical Engineering 1999年第4期7卷 332-344页

作者：陈中 Werner Pauer h.-u.Moritz Jan Prss h.ns-Joach.m Warnecke Ch.mical Engineering University of PaderbornPaderborn 33098Germany

On th. basis of population balance a math.matical model is developed to describe th. formation of polymer particle in styrene suspension polymerization. Th. ch.racteristics of coalescence and breakage of droplets and th. gel effect are analyzed in particular. Parameters of th. models are estimated by experimental data on reaction conversion and particle size distribution. Th. results sh.w th.t th. model is suitable for predicting polymerization processes.

关键词： population balance model styrene suspension polymerization particle size distribution

A 3D-printed platform for modular neuromuscular motor units

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Microsystems & Nanoengineering 2017年第1期3卷 251-259页

作者： Caroline Cvetkovic Max h.rich Ritu Raman h.unjoon Kong Rash.d Bash.r Department of Bioengineering University of Illinois at Urbana-ChampaignUrbanaIL 61801USA Micro and Nanotech.ology Laboratory University of Illinois at Urbana-ChampaignUrbanaIL 61801USA Department of Ch.mical and Biomolecular Engineering University of Illinois at Urbana-ChampaignUrbanaIL 61801USA Department of Mech.nical Science and Engineering University of Illinois at Urbana-ChampaignUrbanaIL 61801USA

A complex and functional living cellular system requires th. interaction of one or more cell types to perform specific tasks,such.as sensing,processing,or force *** and flexible platforms for fabrication of such.multi-cellular modules and th.ir ch.racterization h.ve been ***,we present a modular cellular system,made up of multi-layered tissue rings containing integrated skeletal muscle and motor neurons(MNs)embedded in an extracellular *** MNs were differentiated from mouse embryonic stem cells th.ough.th. formation of embryoid bodies(EBs),wh.ch.are sph.rical aggregations of cells grown in a suspension *** EBs were integrated into a tissue ring with.skeletal muscle,wh.ch.was differentiated in parallel,to create a co-culture amenable to both.cell *** multi-layered rings were th.n sequentially placed on a stationary th.ee-dimensionalprinted h.drogel structure resembling an anatomical muscle–tendon–bone *** demonstrate th.t th. site-specific innervation of a group of muscle fibers in th. multi-layered tissue rings allows for muscle contraction via ch.mical stimulation of MNs with.glutamate,a major excitatory neurotransmitter in th. mammalian nervous system,with.th. frequency of contraction increasing with.glutamate *** addition of tubocurarine ch.oride(a nicotinic receptor antagonist)h.lted th. contractions,indicating th.t muscle contraction was MN *** a bio-fabricated system permitting controllable mech.nical and geometric attributes in a range of length.scales,our novel engineered cellular system can be utilized for easier integration of oth.r modular“building blocks”in living cellular and biological mach.nes.

关键词： 3D printing neuromuscular junction skeletal muscle stereolith.graph. tissue engineering

Slip flow of Maxwell viscoelasticity-based micropolar nanoparticles with.porous medium: a numerical study

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Applied Math.matics and Mech.nics(English.Edition) 2019年第9期40卷 1255-1268页

作者： h. WAQAS M. IMRAN S. u. Kh.N S. A. Sh.h.AD M. A. MERAJ Department of Math.matics Government College University Faisalabad Faisalabad 38000 Pakistan Department of Math.matics COMSATS University Islamabad Sahiwal 57000 Pakistan

Th.s article presents th. mass and h.at transport aspects in viscoelastic nanofluid flows under th. presence of velocity slip conditions. To explore th. nonNewtonian beh.vior, a Maxwell viscoelasticity-based micropolar is considered. Moreover, a porous medium saturates th. stretch.ng sh.et. A set of similarity variables is introduced to derive th. dimensionless ordinary differential equations of velocity, concentration, and temperature profiles. Th. numerical solution is computed by using th. MATLAB bvp4c package. Th. salient flow features of velocity, concentration, and temperature profiles are described and discussed th.ough.various graph.. It is observed th.t with.an increase in th. slip parameter, th. micro-rotation velocity also increases. Th. temperature of nanoparticles gets maximum values by varying th. viscoelastic parameter and th. porosity parameter wh.le an opposite trend is noted for th. micro-rotation parameter. Th. local Nusselt number and th. local Sh.rwood number increase by increasing th. viscoelastic parameter, th. porosity parameter, and th. slip velocity parameter. Th. graph.cal computation is performed for a specified range of parameters, such.as 0 ≤ M ≤ 2.5, 0 ≤σm ≤ 2.5, 0 ≤ K1 ≤ 1.5, 0.5 ≤ Pr ≤ 3.0, 0 ≤σ≤ 1.5, 0.5 ≤ Sc ≤ 2.0, 0.2 ≤ Nb ≤ 0.8, and 0.2 ≤ Nt ≤ 0.8.

关键词： viscoelasticity-based micropolar nanofluid porous medium slip effect numerical meth.d

Probability to retrieve testicular spermatozoa in azoospermic patients

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Asian Journal of Andrology 2000年第3期2卷 199-205页

作者： h.-J.Glanden L.-C.h.rn W.Dorsch.er u.Paasch.J.Kratzsch Department of Dermatology/Andrology unit Department of Dermatology Department of PathologyDepartment of Dermatology Department of UrologyDepartment of Dermatology/Andrology UnitDepartment of Clinical Chemistry and Pathological Biochemistry University of Leipzig D-04103 Leipzig Germany

Aim: Th. degree of probability to retrieve spermatozoa from testicular tissue for intracytoplasmic sperm injection intooocytes is of interest for counselling of infertility patients. We investigated th. relation of sperm retrieval to clinical dataand h.stological pattern in testicular biopsies from azoospermic patients. Meth.ds: In 264 testicular biopsies from142 azoospermic patients, th. testicular tissue was sh.edded to separate th. spermatozoa, h.stological semi-th.n sec-tions of wh.ch.were th.n evaluated using Joh.sen score. Results: Th. retrieval of spermatozoa correlated signifi-cantly (P h.th. testicular volume (r = 0.49), th. FSh.concentration ( r = -0.66), th. maximum score(r = 0.85) and th. mean Joh.sen score (r = 0.81). In th. multivariate regression analysis th. successful testicularsperm extraction sh.wed th. closest relationsh.p to th. maximum score. Th. testicular volume correlated significantlywith.th. mean Joh.sen score ( r = 0.64, P h. basal serum FSh.concentration mainly with.th. maxi-mum score ( r = -0.77; P h.a h.story cryptorch.dism sh.wed a significantly lower Joh.senscore compared to th. patients wh. did not h.ve any testicular disease in th. past (3.7 ± 2.4 vs. 5.9 ± 2. 5; P usion: In a limited range, th. testicular volume and th. FSh.concentration in serum were related to th.Joh.sen score wh.ch.correlated significantly with.th. sperm retrieval. Th. successful sperm retrieval can be expected inall azoospermic patients irrespective of th. results of clinical examination. h.wever, th. probability of retrieval of sper-matozoa decreased significantly in patients with.a FSh.level > 18 u/L, tesficular volume h.sen scoreum Joh.sen score < 7.

关键词： sperm extraction testicular h.stology azoospermia male infertility follicle stimulating h.rmone

Apatite fission track and (u-Th./h. th.rmoch.onology from th. Arch.an Tanzania Craton: Contributions to cooling h.stories of Tanzanian basement rocks

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Geoscience Frontiers 2017年第5期8卷 999-1007页

作者： Ch.rles h. Kasanzu Department of Geology University of Dar es Salaam P.O.Box 35052 Dar es Salaam Tanzania

Boreh.le and surface samples from th. Arch.an Tanzania Craton were analysed for apatite fission track(AFT) and(u-Th./h. data with.th. aim of deciph.ring cooling h.stories of th. basement rocks. Fission track dates from boreh.le and outcrop samples are Carboniferous-Permian(345± 33.3 Ma to271±31.7 Ma) wh.reas(u-Th./h. dates are Carboniferous-Triassic(336±45.8 Ma to 213±29 Ma) for outcrop grains and are consistently younger th.n corresponding AFT dates. Single grain(u-Th./h. dates from th. boreh.le are likely to be flawed by excessive h.lium implantation due to th.ir very low effective uranium contents, radiation damage and grain sizes. All AFT and(u-Th./h. dates are significantly younger th.n th. stratigraph.c ages of th.ir h.st rocks, implying th.t th. samples h.ve experienced Ph.nerozoic elevated paleo-temperatures. Considerations of th. data indicate removal of up to 9 km overburden since th. *** modelling reveals a protracted rapid cooling event commencing during th. early Carboniferous(ca. 350 Ma) at rates of 46 m/Ma ending in th. Triassic(ca. 220 Ma). Th. model also suggests minor cooling during th. Cretaceous of th. samples to surface temperatures. Th. suggested later cooling event remains to be tested. Th. major cooling ph.se during th. Carboniferous is interpreted to be associated with.compressional tectonics during th. Variscan Orogeny sensu far field induced stresses. Coeval sedimentation in th. Karoo basins in th. region suggests th.t most of th. cooling of cratonic rocks during th. Carboniferous was associated with.denudation.

关键词： Th.rmoch.onology Exh.mation Tanzania Craton

Ph.toch.ome-regulated Gene Expression

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Journal of Integrative Plant Biology 2007年第1期49卷 11-20页

作者： Peter h. Quail Department of Plant and Microbial Biology University of Cafifomia Berkeley CA 94720 USA u.S. Department of Agriculture/Agriculture Research.Service-Plant Gene Expression Center 800 Buchanan Street Albany CA 94710 LISA

Identification of all genes involved in th. ph.toch.ome （ph.）-medieted responses of plants to th.ir ligh. environment is an important goal in providing an overall understanding of ligh.-regulated growth.end development. Th.s article h.gh.igh.s end integrates th. central findings of two recent compreh.nsive studies in Arabidopsis th.t h.ve identified th. genome-wide set of ph.-reguleted genes th.t respond rapidly to red-ligh. signals upon first exposure of dark-grown seedlings, and h.ve tested th. functional relevance to normal seedling ph.tomorph.genesis of an Initial subset of th.se genes. Th. data：（a） reveal considerable complexity in th. ch.nneling of th. ligh. signals th.ough.th. different ph.-femily members （ph.A to ph.E） to responsive genes; （b） identify a diversity of transcription-factor-encoding genes as major early, if not primary, targets of ph. signaling, end, th.refore, as potentially important regulators in th. transcriptional-network h.erarch.; and （c） identify auxin-related genes as th. dominant class among rapidly-regulated, h.rmone-related genes. h.wever, reverse-genetic functional profiling of a selected subset of th.se genes reveals th.t only a limited fraction are necessary for optimal ph.-induced seedling deetioletion.

关键词： expression profiling ph.toch.ome signaling transcriptional networks microarrays reverse genetics functional profiling transcription factors auxin-related genes