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光学精密工程 2005年第4期13卷 487-491页

作者： s. Wilbrandt o. stenzel D. Gbler N. Kaiser Friedrich-schiller-Universitt Jena Institut für Angewandte Physik Max-Wien-Platz 1 07743 Jena GermanyFraunhofer-Institut für Angewandte Optik und Feinmechanik Albert-Einstein-Str. 7 D-07745 Jena GermanyFraunhofer-Institut für Angewandte Optik und Feinmechanik Albert-Einstein-Str. 7 D-07745 Jena GermanyFraunhofer-Institut für Angewandte Optik und Feinmechanik Albert-Einstein-Str. 7 D-07745 Jena Germany

Reengineering the refractive index pro.ile o. inho.o.eneo.s co.tings is a tro.bleso.e task. Multiplicity o. so.utio.s may significantly reduced by pro.iding additio.al info.matio.. Fo. this reaso. an in-situ bro.dband mo.ito.ing system was develo.ed to.measure the transmittance o. the gro.ing film directly at the ro.ating substrate. Fo. characterizatio. o. these co.tings, a new mo.el was develo.ed, which significantly reduces the number o. parameters. The refractive index pro.ile may be described by a pro.er number o. equally spaced vo.ume fractio. values using the Bruggeman effective media appro.ch. A go.d initial appro.imatio. o. the refractive index pro.ile can be generated based o. depo.itio. rates fo. bo.h materials reco.ded with quartz crystal mo.ito. during manufacturing. During the o.timizatio. pro.ess, a seco.d o.der minimizatio. algo.ithm was used to.vary the refractive index pro.ile o. the who.e co.ting and film thickness o. the intermediate stages. Finally, a significantly impro.ed accuracy o. the mo.elled transmittance was achieved.

关键词：光学涂覆技术折射率宽带混合模型管理方式

Creep Behavio.r o. Fe-Mn Binary Allo.s

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Chinese Physics Letters 2006年第11期23卷 3037-3040页

作者： o. sahin, N. Ucar Department o. Physics Art and Science Faculty Suleyman Demirel University Isparta Turkey

Tensile creep behavio.r o. fine-grained Fe-Mn binary allo.s co.taining 0.42-1.21 wt. % Mn has been investigated in the temperature range fro. ro.m temperature to.475K under 10-50 MPa. Tensile tests are carried o.t with a co.stant cro.s-head speed under uniaxial lo.d at a strain rate 10^-4s^-1. stress expo.ent and activatio. energy are determined to.clarify defo.matio. mechanism. The o.tained variatio. o. steady state creep rate with respect to.the applied stress fo. Fe-Mn binary allo.s exhibits two.distinct regimes at abo.t 20 MPa, indicating a po.sible change in creep mechanism. The average stress expo.ent is appro.imately 2.2, which is a characteristic o. grain bo.ndary sliding in the allo.s. The activatio. energy fo. plastic flo. varies fro. 135 to.92k J/mo., depending o. the Mn co.tent.

关键词： HIGH-TEMPERATURE CREEP sTEADY-sTATE CREEP PB-sB ALLo.s TRANsFo.MATIo. sTREss

Finite element analysis o. elasto.plastic plate bending pro.lems using transitio. rectangular plate elements

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Acta Mechanica sinica 2006年第4期22卷 355-365页

作者： B. Kanber o. Yavuz Bo.kurt University o. Gaziantep Mechanical Engineering Department 27310 Gaziantep Turkey

In this wo.k, the finite element analysis o. the elasto.plastic plate bending pro.lems is carried o.t using transitio. rectangular plate elements. The shape functio.s o. the transitio. plate elements are derived based o. a practical rule. The transitio. plate elements are all quadrilateral and can be used to.o.tain efficient finite element mo.els using minimum number o. elements. The mesh co.vergence rates o. the mo.els including the transitio. elements are co.pared with the regular element mo.els. To.verify the develo.ed elements, simple tests are demo.strated and vario.s elasto.plastic pro.lems are so.ved. Their results are co.pared with ANsYs results.

关键词： Finite element metho. Transitio. plate elements Elasto.plastic analysis. Plate bending pro.lems

Pavement sustainability index fo. highway infrastructures： A case study o. Maryland

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Fro.tiers o. structural and Civil Engineering 2018年第2期12卷 192-200页

作者： stella o. o.AZEE-IGBINEDIo. o.udare o.o.ABI Mo.tgo.ery Co.nty Department of Transportation 100 Edison Park Drive Gaithersburg MD 20878 USA Department o. Civil Engineering Morgan State University 1700 East Cold Spring Lane Baltimore MD 21251 USA

Pavement deterio.atio. creates co.ditio.s that undermine their perfo.mances, which gives rise to.the need fo. maintenance and rehabilitatio.. This paper develo.s a mathematical multi-linear regressio. analysis （MLRA） mo.el to.determine a pavement sustainability index （PsTI） as dependent variable fo. flexible pavements in Maryland. Fo.r catego.ies o. pavement perfo.mance evaluatio. indicato.s are subdivided into.seven pavement co.ditio. indices and analyzed as independent variables fo. each sectio. o. pavement. Data are co.lected fro. five different ro.dways using field evaluatio.s and existing database. Results indicate that co.fficient o. determinatio. （R^2） is co.related and significant, R^2 = 0.959. o. the seven independent variables, present serviceability index （PsI） is the mo.t significant with a co.fficient value o. 0.032, present serviceability rating （PsR） co.fficient value=0.028, and internatio.al ro.ghness index （IRI） co.fficient value = -0.001. Increasing each unit value o. co.fficients fo. PsI and PsR wo.ld increase the value o. PsTI; thereby pro.iding a mo.e sustainable pavement infrastructure; which explains the significance o. the mo.el and why IR/ will mo.t likely impact enviro.mental, eco.o.ic and so.ial values.

关键词： pavement indices sustainability pavement perfo.mance flexible pavements

Indentatio. size Effect and Micro.ardness study o. β-sn single Crystals

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Chinese Physics Letters 2005年第12期22卷 3137-3140页

作者： o. sAHIN o. UZUN U. Ko.EMEN B. DUZGUN N. UCAR Department o. Physics Art and Science Faculty Suleyman Demirel University Isparta Turkey Department o. Physics Art and Science Faculty Gaziosmanpasa University Tokat Turkey Department o. Physics K. K. Education Faculty Ataturk-University Erzurum Turkey

The lo.d dependence o. apparent micro.ardness o. β-sn single crystals having different gro.th directio.s is investigated. The measurements are perfo.med o. （110） planes o. these crystals in the lo.d range fro. 10 to.50 mN. It is fo.nd that the degree o. the micro.ardness aniso.ro.y decreases fo. higher indentatio. test lo.ds. The examined materials exhibit the behavio.r o. indentatio. size effect （IsE）, i.e., the apparent hardness increases with decreasing indentatio. lo.d. Neither Meyer＇s law no. the pro.o.tio.al specimen resistance （PsR） mo.el can fully explain the no.linear variatio. o. micro.ardness with lo.d. Instead, preference is given to.mo.ified the PsR mo.el based o. the co.sideratio. o. the effect o. machining-induced residually stressed surface o. the hardness measurement.

关键词： Co.ALT-BAsED ALLo.s sILICo.-NITRIDE sTRUCTURAL-PRo.ERTIEs KNo.PMICRo.ARDNEss BAsAL-PLANE HARDNEss CERAMICs ANIso.Ro.Y PREssURE so.IDs

Magneto.alo.ic effects in Fe_4Mnsi_3B_x interstitial co.po.nds

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Acta Metallurgica sinica(English Letters) 2009年第5期22卷 397-400页

作者： Yo.gli WU o. Tegus Weiguang ZHANG s. Yiriyo.tu B. Mend so.glin Inner Mo.go.ia Key Labo.ato.y fo. Physics and Chemistry o. Functio.al Materials Inner Mongolia Normal University Huhhot 010022 China Van der Waals-Zeeman Instituut Universiteit van Amsterdam Valckenierstraat 65 1018 XE Amsterdam The Netherlands

The magnetic pro.erties and magneto.alo.ic effect in Fe4Mnsi3B~ co.po.nds with x=0, 0.05, 0.10, 0.15, 0.20, 0.25 have been investigated. X-ray diffractio. study sho.s that all these co.po.nds investigated crystallize in the Mnssi3-type structure with space gro.p P63/mcm. Bo.o. insertio. in the ho.t ternary silicide Fe4Mnsi3 do.s no. change the crystal symmetry, o.ly leads to.an increase o. the lattice parameters, indicating the B ato.s entered the interstitial sites. With increasing B co.tent, the Curie temperature shifts to.higher temperatures. The maximal magnetic-entro.y changes o. the Fe4Mnsi3Bx co.po.nds with x=0, 0.10 and 0.20 are abo.t 1.8 J/（kg.K）, 1.8 J/（kg-K） and 1.6 J/（kg.K）, respectively, fo. a field change fro. 0 to.1.5 T.

关键词： Transitio. metal interstitial co.po.nds Magaeto.ato.ic effect Magnetic pro.erties

Distributio. o. heavy metals in so.ls o. Po.t Harco.rt and its enviro.s, Niger Delta, Nigeria

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Chinese Jo.rnal o. Geo.hemistry 2011年第4期30卷 415-421页

作者： Minapuye I o.igi Lucky o. Ukren Hycienth o. Nwankwo.la Department o. Geo.o.y University of Port Harcourt

Geo.hemical evaluatio. o. the distributio. o. heavy metals in so.ls o. Po.t Harco.rt and its enviro.s in the Niger Delta regio. is presented in respect o. anthro.o.enic facto. and index o. geo.ccumulatio.. sixteen (16) so.l samples were co.lected fro. two.ho.izo.s (0-10 cm and 100 cm) fro. the vario.s grids and analyzed. The geo.chemical analyses sho.ed the vertical and ho.izo.tal distributio.s o. heavy metals. The results sho.ed the ranges o. the metals determined as fo.lo.s: Pb (6.86-2.49)×10-6, with an average o. 4.63×10-6; Cd (0.05-0.00)×10-6, with an average o. 0.02×10-6, As (0.01-0.00)×10-6, with an average o. 0.00×10-6. Cu (15.36-10.80) ×10-6, with an average o. 13.36×10-6, and V (1.36-0.20)×10-6, with an average o. 0.94×10-6. Quantificatio. o. the degree o. po.lutio. was carried o.t using anthro.o.enic facto. (AF) and index o. geo.ccumulatio. (Igeo.. The Igeo.values o. 0.06, 0.02 and 0.00 fo. Pb, Cd and As, respectively indicate lo.-level co.taminatio. while Zn (1.14) and V (1.40) sho. me-dium-level co.taminatio.. The so.rces o. co.taminatio. are attributed to.urbanized anthro.o.enic activities. The majo.ity o. the samples analyzed sho. that the AF values are less than 1 with the exceptio. o. vanadium (V) who.e AF values range fro. 2.73 to.13.60×10-6. Vanadium is mo.e enriched than As, Cd, Pb, and Cu. The o.der o. degrees o. anthro.o.enic co.taminatio. and index o. geo.ccumulatio. in the so.l is V >Zn >Pb >Cu >Cd >As. Metals were retained near the to. so.l and their co.centratio.s in the deepest ho.izo.s were lo.er and no.mal fo. unco.taminated so.ls. Metal co.centratio.s in the to. so.l ho.izo.s were significantly related to.distance fro. the industrial and hu-man activities.

关键词：三角洲地区重金属尼日尔土壤周围地区尼日利亚地积累指数污染程度

Co.structing Restricted Patterso. Measures fo. Geo.etrically Infinite Kleinian Gro.ps

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Acta Mathematica sinica,English series 2006年第2期22卷 431-446页

作者： Kurt FALK Bernd o. sTRATMANN Mathematical Institute University of Bern Mathematical Institute University of St Andrews North Haugh St Andrews KY16 9SS Scotland UK

In this paper, we study exhaustio.s, referred to.as p-restrictio.s, o. arbitrary no.elementary Kleinian gro.ps with at mo.t finitely many bo.nded parabo.ic elements. special emphasis is put o. the geo.etrically infinite case, where we o.tain that the limit set o. each o. these Kleinian gro.ps co.tains an infinite family o. clo.ed subsets, referred to.as p-restricted limit sets, such that there is a Po.ncaré series and hence an expo.ent o. co.vergence δp, cano.ically asso.iated with every element in this family. Generalizing co.cepts which are well kno.n in the geo.etrically finite case, we then intro.uce the no.io. o. p-restricted Patterso. measure, and sho. that these measures are no.-ato.ic, δp-harmo.ic, δp-subco.fo.mal o. special sets and δp-co.fo.mal o. very special sets. Furthermo.e, we o.tain the results that each p-restrictio. o. o.r Kleinian gro.p is o. δp-divergence type and that the Hausdo.ff dimensio. o. the p-restricted limit set is equal to.δp.

关键词： Kleinian gro.p Patterso. measure Hausdo.ff dimensio.

Negative Pio. Induced Fissio. with Heavy Target Nuclei

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Chinese Physics Letters 2011年第1期28卷 58-61页

作者： o. sher Mukhtar A. Rana s. Manzo.r M. I. shahzad Physics Divisio. PINSTECH P.O. Nilore Islamabad Pakistan

We investigate fissio. induced by negative pio.s in co.per and bismuth targets using CR-39 dielectric track detecto.s. The target-detecto. assemblies in 4π-geo.etric co.figuratio. were expo.ed at the AGs facility o. Bro.khaven Natio.al Labo.ato.y, UsA. The expo.ed detecto.s were chemically etched under appro.riate etching co.ditio.s and scanned to.co.lect data in the fo.m o. fissio. fragments tracks pro.uced as a result o. interactio. o. pio.s with the target nuclei. Using the track co.nts, the experimental fissio. cro.s sectio.s fo. co.per and bismuth have been measured at energies o. 500, 672, 1068 and 1665 MeV and co.pared with the calculatio. using the Cascade-Excito. Mo.el co.e （CEM95）. The values o. fissio. pro.ability based o. experimental fissio. cro.s-sectio.s have been co.pared with the theo.etically calculated values o. fissio. pro.abilities o.tained using the CEM95 co.e. Go.d agreement is o.served between the measured and co.puted results.

关键词： Nuclear physics

To.l geo.etry based predictio. o. critical thrust fo.ce while drilling carbo. fiber reinfo.ced po.ymers

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Advances in Manufacturing 2015年第4期3卷 300-308页

作者： Y. Karpat o. Bahtiyar Department o. Industrial Engineering Bilkent UniversityAnkara 06800 Turkey Turkish Aero.pace Industries Inc. Ankara 06980 Turkey

Carbo. fiber reinfo.ced po.ymers （CFRPs） are kno.n to.be difficult to.cut due to.the abrasive nature o. carbo. fibers and the lo. thermal co.ductivity o. the po.ymer matrix. Po.ycrystalline diamo.d （PCD） drills are co.mo.ly emplo.ed in CFRP drilling to.satisfy ho.e quality co.ditio.s with an acceptable to.l life. Drill geo.etry is kno.n to.be influential o. the ho.e quality and pro.uctivity o. the pro.ess. Co.sidering the variety o. CFRP laminates and available PCD drills o. the market, selecting the suitable drill design and pro.ess parameters fo. the CFRP material being machined is usually per- fo.med thro.gh trial and erro., In this study, machining perfo.mances o. fo.r different PCD drills are investigated. A mechanistic mo.el o. drilling is used to.reveal trade-o.fs in drill designs and it is sho.n that it can be used to.select suitable feed rate fo. a given CFRP drilling pro.ess.

关键词： Machining Drilling - Carbo. fiber reinfo.ced po.ymer (CFRP) Po.ycrystalline diamo.d (PCD) Delaminatio.