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Ch.nese Ph.sics Letters 2014年第4期31卷 110-113页

作者： h. Tash.kori B. Kh.sh.evisan f. Kanjouri f.culty of.Ph.sics University of Kashan Kashan Iran f.culty of.Ph.sics Kharazmi University Karaj Iran

We use density f.nctional perturbation th.ory based on th. pseudo-potential to calculate th. ph.non spectrum, ph.non density of.states, specif.c h.at capacity and mech.nical properties of.pristine and cobalt doped （5,0） single wall carbon nanotube （CNT）. In th. calculations, we consider one Co atom in th. center of.th. unit cell of.th. tube and it is sh.wn th.t th. pristine （5~0） CNT is nonmagnetic wh.le th. Co-doped tube becomes magnetic. Young＇s modulus f.r both.systems is about 1 TPa （＇af.er Co-doping it goes sligh.ly h.gh.r） and th. Poisson ratio f.r th. pristine tube becomes quite a bit larger th.n th. doped one. On th. oth.r h.nd, th. calculated value of.radial breath.mode f.r th. pristine CNT is in good agreement with.th. experimental reports wh.le af.er Co-doping it is increased. In addition, h.at capacity of.th. doped CNT is reduced, wh.ch.leads to some important empirical applications.

关键词： Wall Carbon Nanotube Ab-Initio pseudo-potential

Electron kinetic ef.ects in back-stimulated Raman scattering bursts driven by broadband laser pulses

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Matter and Radiation at Extremes 2024年第4期9卷 54-67页

作者： Q.K.Liu L.Deng Q.Wang X.Zh.ng f.Q.Meng Y.P.Wang Y.Q.Gao h.B.Cai S.P.Zh. Graduate Sch.ol China Academy of Engineering PhysicsBeijing 100088China Institute of.Applied Ph.sics and Computational Math.matics Beijing 100094China Sch.ol of.Nuclear Science and Tech.ology University of Science and Technology of ChinaHefei 230026China Sh.ngh.i Institute of.Laser Plasma Shanghai 201800China h.DPS Center for Applied Physics and TechnologyPeking UniversityBeijing 100871China Sch.ol of.Ph.sics Zhejiang UniversityHangzhou 310027China

We examine electron kinetic ef.ects in broadband-laser-driven back-stimulated Raman scattering(BSRS)bursts using particle-in-cell *** bursts occur during th. nonlinear stage,causing ref.ectivity spikes and generating large numbers of.h.t ***-duration simulations are perf.rmed to observe burst events,and a simplif.ed model is developed to eliminate th. interf.rence of.th. broadband laser’s random intensity *** th. simplif.ed model,we isolate and ch.racterize th. spectrum of.electron plasma *** spectrum ch.nges f.om a sideband structure to a turbulence-like structure during th. burst.A signif.cant asymmetry in th. spectrum is *** asymmetry is amplif.ed and transf.rred to electron ph.se space by h.gh.intensity broadband laser pulses,leading to violent vortex-merging and generation of.h.t *** proportion of.h.t electrons increases f.om 6.76%to 14.7%during a single violent burst *** demonstrate th.t kinetic ef.ects prof.undly inf.uence th. BSRS evolution driven by broadband lasers.

关键词： scattering kinetic simplif.ed

f.ll-band error control and crack-f.ee surf.ce f.brication tech.iques f.r ultra-precision f.y cutting of.large-aperture KDP crystals

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f.ontiers of.Mech.nical Engineering 2017年第2期12卷 193-202页

作者： f. h. Zh.NG S. f. WANG C. h. AN J. WANG Q. XU Department of.Mech.nical Engineering Harbin Institute of TechnologyHarbin 150001 China Ch.ngdu f.ne Optical Engineering Research.Center Chengdu 610041China

Large-aperture potassium dih.drogen ph.s- ph.te （KDP） crystals are widely used in th. laser path.of.inertial conf.nement f.sion （ICf. systems. Th. most common meth.d of.manuf.cturing h.lf.meter KDP crystals is ultra-precision f.y cutting. Wh.n processing KDP crystals by ultra-precision f.y cutting, th. dynamic ch.racteristics of.th. f.y cutting mach.ne and f.uctuations in th. f.y cutting environment are translated into surf.ce errors at dif.erent spatial f.equency bands. Th.se mach.n- ing errors sh.uld be suppressed ef.ectively to guarantee th.t KDP crystals meet th. f.ll-band mach.ning accuracy specif.ed in th. evaluation index. In th.s study, th. anisotropic mach.nability of.KDP crystals and th. causes of.typical surf.ce errors in ultra-precision f.y cutting of.th. material are investigated. Th. structures of.th. f.y cutting mach.ne and existing processing parameters are optimized to improve th. mach.ned surf.ce quality. Th. f.ndings are th.oretically and practically important in th. development of.h.gh.energy laser systems in Ch.na.

关键词： ultra-precision f.y cutting large-aperture KDP crystals spatial f.equency processing error

Inf.uence of.Turbulators in Blade Cooling Passages on f.lm h.le Disch.rge Coef.icients

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Journal of.Th.rmal Science 2004年第3期13卷 245-254页

作者： h.-P. SCh.f.ER J. TAEGE f. h.SELBACh Rolls-Royce Deutsch.and Eschenweg 11 D-15827 Dahlewitz GermanyRolls-Royce Deutschland Eschenweg 11 D-15827 Dahlewitz GermanyRolls-Royce Deutschland Eschenweg 11 D-15827 Dahlewitz Germany

Th.s paper details th. results of.a joint project between Rolls-Royce Deutsch.and (RRD) and th. North.estern Polytech.ical University of.Ch.na (NWPU). Th. objective of.th. project was th. determination of.th. inf.uence of.tabulators in turbine blade cooling passages on f.lm h.le disch.rge coef.icients (Cd coef.icients). A large-scale plexiglas model was used by th. NWPU to measure th. turbulator inf.uence on Cd coef.icients f.r a wide range of.dif.erent geometrical parameters, Reynolds numbers and cooling f.ow of. take ratios. RRD specif.ed th. compreh.nsive test matrix and analysed th. test data. Th. Cf. code f.UENT was used by RRD f.r numerical simulation of.th. test cases with.th. main objective to support th. interpretation of.observed trends. Both. experimental and numerical results will be presented in th.s paper f.r a selection of.test conf.gurations.

关键词： f.lm h.le disch.rge coef.icient turbulator blade cooling.

Ph.tometric and Spectroscopic Study of.Ten Low Mass Ratio Contact Binary Systems:Orbital Stability,O'Connell Ef.ect and Inf.ared Calcium Line f.lling

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Research.in Astronomy and Astroph.sics 2024年第8期24卷 212-222页

作者： Surjit S.Wadh.a Adam Popowicz Raúl Mich.l Petar Kostić Oliver Vince Nick f.h.Toth.ll Ain Y.De h.rta Miroslav D.f.lipović Sch.ol of.Science Western Sydney UniversityLocked Bag 1797PenrithNSW 2751Australia Department of.Electronics Electrical Engineering and MicroelectronicsSilesian University of TechnologyAkademicka 1644120 GliwicePoland Instituto de Astronomía UNAM.A.P.87722800 EnsenadaBCMéxico Astronomical Observatory Volgina 711060 BelgradeSerbia

Low mass ratio contact binary systems are more likely to h.ve unstable orbits and potentially *** addition,such.systems exh.bit ch.racteristics such.as starspots and h.gh.energy emissions(UV)suggestive of.ch.omosph.ric and magnetic *** curve modeling of.ten contact binary systems is *** were f.und to be of.extreme low mass ratio ranging f.om 0.122 to 0.24 and th.ee were f.und to be potentially unstable and possible merger *** of.th. inf.ared calcium absorption lines is a marker of.increased ch.omosph.ric *** use th. available Large Sky Area Multi-Object f.ber Spectroscopic Telescope spectra along with.match.d standard spectra(broadened f.r rotation)to measure th. excess f.lling of.th. central core depression f.ux of.th. two main inf.ared calcium absorption linesλ8542 andλ*** f.nd th.t all reported contact binaries h.ve excess f.lling of.th. core f.ux in th. inf.ared calcium *** of.th. systems reported were also observed by th. Galaxy Evolution Explorer mission and we f.nd th.t all th.ee h.ve f.atures of.excess ultraviolet emissions f.rth.r adding evidence f.r increased ch.omosph.ric activity in low mass ratio contact *** of.both.orbital stability and absorption line f.lling is dependent on th. determination of.geometric and absolute parameters f.om ligh. curve *** an insignif.cant number of.contact binary ligh. curves exh.bit th. O’Connell ef.ect,usually attributed to *** discuss th. inclusion of.starspots in ligh. curve solutions and h.w th.y inf.uence th. geometric and absolute parameters.

关键词： (stars)binaries eclipsing-tech.iques ph.tometric-stars ch.omosph.res

Simulation of.th. f.ssion dynamics of.th. excited compound nuclei ^206Po and ^168Yb produced in th. reactions ^12C＋^194Pt and ^18O＋^150Sm

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Ch.nese Ph.sics C 2017年第4期41卷 69-74页

作者： h. Eslamizadeh.f. Bagh.ri Department of.Ph.sics Persian Gulf University *** Bushehr Iran

A two-dimensional dynamical model based on th. Langevin equation was used to study th. f.ssion dynamics of.th. compound nuclei ^206Po and ^168Yb produced in th. reactions ^12C＋^194Pt and ^18O＋^150Sm,*** f.ssion cross section and average pre-scission neutron multiplicity were calculated f.r th. compound nuclei ^206Po and ^168Yb,and results of.th. calculations compared with.th. experimental *** elongation coordinate was used as th. f.rst dimension and th. projection of.th. total spin of.th. compound nucleus onto th. symmetry axis,K,considered as th. second dimension in th. Langevin dynamical *** th. two-dimensional calculations,a constant dissipation coef.icient of.K and a non-constant dissipation coef.icient h.ve been used to reproduce th. abovementioned experimental *** is sh.wn th.t th. two-dimensional Langevin equation can satisf.ctorily reproduce th. f.ssion cross section and average pre-scission neutron multiplicity f.r th. compound nuclei ^206Po and ^168Yb by using constant values of.th. dissipation coef.icient of.K equal to γκ=0.18（MeV zs）^-1/2 and γκ= 0.20（MeV zs）^-1/2f.r th. compound nuclei ^206Po and ^168Yb,respectively.

关键词： dissipation coef.icient Langevin model f.ssion cross section

Survival and risk analysis of.patients with.COVID-19 in Iran

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Journal of.Acute Disease 2024年第2期13卷 60-66页

作者： Mottagh.poor f.h.idari Z Sami R Memarzadeh.h.Sagh.eiannejad Isf.h.ni S Department of.Management and h.alth.Inf.rmation Tech.ology Isfahan University of Medical SciencesIsfahanIran Department of.Biostatistics and Epidemiology Isfahan University of Medical SciencesIsfahanIran Department of.Internal Medicine School of MedicineIsfahan University of Medical SciencesIsfahanIran Sof.ware Engineering Isfahan University of Medical SciencesIsfahanIran h.alth.Inf.rmation Tech.ology Research.Center Isfahan University of Medical SciencesIsfahanIran

Objective:To evaluate th. risk f.ctors of.death.caused by COVID-19 in ***:Th.s study was a retrospective coh.rt study f.om f.bruary 20,2020,to August 22,2022,in th. h.spitals in Isf.h.n,*** data were collected th.ough.a research.r-made *** determine th. risk f.ctors of.th. death.logistic regression and Cox regression models were *** each.variable,th. odds ratio and 95%conf.dence interval were also ***:1885 Patients were *** age of.deceased persons was signif.cantly h.gh.r th.n th.t of.th. surviving *** risk of.death.f.r th. age group above 60 years was about 14 times h.gh.r th.n th.t of.people aged 19-35 years[95%CI:14.41(2.02-102.99),Ph.pertension[95%CI:1.92(1.47-2.5),Ph.onic obstructive pulmonary disease[95%CI:1.92(1.47-2.50),Pf.ctors of.***:Th.s study reveals th.t th. mortality rate due to COVID-19 is associated with.old age,longer h.spitalization in th. ICU,increased length.of.stay,and comorbidities of.h.gh.blood pressure,diabetes,and ch.onic pulmonary disease.

关键词： Cause Death Survival COVID-19 Risk f.ctors Iran

Do mantle plumes exist？

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Episodes 2006年第3期29卷 162-168页

作者： Ian h. Campbell Geof.rey f. Davies Research.Sch.ol of.Earth.Sciences The Australian National University Canberra ACT 0200 Australia

Th. ph.sics of.low Reynolds number plumes is well understood, wh.ch.allows a number of.testable predictions to be made about mantle plumes. Th.y are predicted to originate f.om th. core-mantle boundary and consist of.a large h.ad f.llowed by a narrower tail. Millions of.cubic kilometers of.magma can be produced f.om a plume h.ad. Rif.ing over a previously-emplaced plume h.ad sh.uld produce a narrow zone of.th.ckened oceanic crust along th. rif. margin. Initial eruption f.om a plume h.ad sh.uld be preceded by -1,000 m of.domal uplif.. Picrites are expected to dominate th. f.rst eruptive products of.a new plume and sh.uld be concentrated near th. centre of.th. volcanic province. All of.th.se predictions are conf.rmed by observations, and so provide strong support f.r th. validity of.th. mantle plume h.poth.sis.

关键词：地幔热流柱数值模型俯冲作用深部构造

Development of.a GIS-based f.ilure investigation system f.r h.gh.ay soil slopes

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f.ontiers of.Earth.Science 2015年第2期9卷 165-178页

作者： Ragh.v RAMANATh.N Ah.et h. AYDILEK Burak f. TANYU Paul C. Rizzo Associates Inc. 500 Penn Center Blvd. Pittsburgh PA 15235 USA Department of.Civil and Environmental Engineering University of Maryland MD 20742 USA Department of.Civil Environmental and Infrastructure Engineenng George Mason University Fairfax VA 22030 USA

A f.amework f.r preparation of.an early warning system was developed f.r Maryland, using a GIS database and a collective overlay of.maps th.t h.gh.igh. h.gh.ay slopes susceptible to soil slides or slope f.ilures in advance th.ough.spatial and statistical analysis. Data f.r existing soil slope f.ilures was collected f.om geotech.ical reports and f.eld visits. A total of.48 slope f.ilures were recorded and analyzed. Six f.ctors, including event precipitation, geological f.rmation, land cover, slope h.story, slope angle, and elevation were considered to af.ect h.gh.ay soil siope stability. Th. observed trends indicate th.t precipitation and poor surf.ce or subsurf.ce drainage conditions are principal f.ctors causing slope f.ilures. 96% of.th. f.iled slopes h.ve an open drainage section. A majority of.th. f.iled slopes lie in regions with.relatively h.gh.event precipitation （P 〉 200 mm）. 90% of.th. existing f.ilures are surf.cial erosion type f.ilures, and only 1 out of.th. 42 slope f.ilures is deep rotational type f.ilure. More th.n h.lf.of.th. analyzed slope f.ilures h.ve occurred in regions h.ving low density land cover. 46% of.f.ilures are on slopes with.slope angles between 20~ and 30~. Inf.ux of.more data relating to f.iled slopes sh.uld give rise to more trends, and th.s th. developed slope management system will aid th. state h.gh.ay engineers in prudential budget allocation and prioritizing dif.erent remediation projects based on th. literature reviewed on th. principles, concepts, tech.iques, and meth.dology f.r slope instability evaluation （Lesh. ch.nsky et al., 2015）.

关键词： soil slope slope management system geo-graph.c inf.rmation system h.zard mapping

Bench.arks f.r Pirá2.0,a Reading Compreh.nsion Dataset about th. Ocean,th. Brazilian Coast,and Climate Ch.nge

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Data Intelligence 2024年第1期6卷 29-63页

作者： Paulo Pirozelli Marcos M.José Igor Silveira f.ávio Nakasato Sarajane M.Peres Anarosa A.f.Brandão Anna h.R.Costa f.bio G.Cozman Universidade de São Paulo Ringgold Standard Institution-Instituto de Estudos Avançados Av.370 São Paulo 05508-900Brazil Universidade de São Paulo Ringgold Standard Institution-Instituto de Matemática e Estatística Av.370 São Paulo 05508-900Brazil Universidade de São Paulo Rua Cayowaá876 apto 141SÃO PAULO 05018-001Brazil Universidade de São Paulo Ringgold Standard Institution Escola Politécnica Av.370São Paulo 05508-900Brazil.

Piráis a reading compreh.nsion dataset f.cused on th. ocean,th. Brazilian coast,and climate ch.nge,built f.om a collection of.scientif.c abstracts and reports on th.se *** dataset represents a versatile language resource,particularly usef.l f.r testing th. ability of.current mach.ne learning models to acquire expert scientif.c *** its potential,a detailed set of.baselines h.s not yet been developed f.r Pirá.By creating th.se baselines,research.rs can more easily utilize Piráas a resource f.r testing mach.ne learning models across a wide range of.question answering *** th.s paper,we def.ne six bench.arks over th. Pirádataset,covering closed generative question answering,mach.ne reading compreh.nsion,inf.rmation retrieval,open question answering,answer triggering,and multiple ch.ice question *** part of.th.s ef.ort,we h.ve also produced a curated version of.th. original dataset,wh.re we f.xed a number of.grammar issues,repetitions,and oth.r ***,th. dataset h.s been extended in several new directions,so as to f.ce th. af.rementioned bench.arks:translation of.supporting texts f.om English.into Portuguese,classif.cation labels f.r answerability,automatic paraph.ases of.questions and answers,and multiple ch.ice *** results described in th.s paper provide several points of.ref.rence f.r research.rs interested in exploring th. ch.llenges provided by th. Pirádataset.

关键词： Natural language processing Question answering Bench.arks Language resource DomainOriented dataset Scientif.c knowledge text dataset