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Deep bed fil.ration model.for cake fil.ration and erosion

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Appl.ed Mathematics and Mechanics(Engl.sh Edition) 2024年第2期45卷 355-372页

作者： l.I.KUZMINA y.V.OSIPOV A.R.PESTEREV Department of Appl.ed Mathematics HSE UniversityMoscow 101000Russia Department of Computer Science and Appl.ed Mathematics Moscow State University of Civil EngineeringMoscow 129337Russia

Many phenomena in nature and technol.gy are associated with the fil.ration of suspensions and col.oids in porous media. Two main types of particl. deposition,namel., cake fil.ration at the inl.t and deep bed fil.ration throughout the entire porous medium, are studied by different model.. A unified approach for the transport and deposition of particl.s based on the deep bed fil.ration model.is proposed. A variabl. suspension fl.w rate, proportional.to the number of free pores at the inl.t of the porous medium, is considered. To model.cake fil.ration, this fl.w rate is introduced into the mass bal.nce equation of deep bed fil.ration. For the cake fil.ration without deposit erosion,the suspension fl.w rate decreases to zero, and the suspension does not penetrate deep into the porous medium. In the case of the cake fil.ration with erosion, the suspension fl.w rate is nonzero, and the deposit is distributed throughout the entire porous medium. An exact sol.tion is obtained for a constant fil.ration function. The method of characteristics is used to construct the asymptotics of the concentration front of suspended and retained particl.s for a fil.ration function in a general.form. Expl.cit formul.e are obtained for a l.near fil.ration function. The properties of these sol.tions are studied in detail.

关键词： deep bed fil.ration cake fil.ration porous medium particl. deposition and erosion anal.tical.sol.tion concentration front

Effect of radiative l.ss mechanisms on FIR thermometric parameters of Nd^(3+)-doped l.thium tel.urite gl.sses

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Journal.of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： C.y.Morassuti A.P.l.Sil.a l.A.O.Nunes S.M.l.ma l.H.C.Andrade Optical.and Photothermal.Spectroscopy Group(GEOF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Archer Information Technol.gy Center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of São Carl.s University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tel.urite gl.sses are promising material. for thermometers based on the fl.orescence intensity ratio(FIR)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical.reabsorption and cross-rel.xation can affect the Nd^(3+)emission,which has been l.ttl. expl.red in the ***,the present work investigated the use of Nd^(3+)-doped tel.urite gl.ss(sampl.s doped with Nd^(3+)at 0.2 mol.,0.5 mol.,2.0 mol.,and 4.0 mol.)in fl.orescence thermometers,in the temperature range from 299 to 371 *** resul.s indicate a strong dependence of the FIR parameters on the Nd^(3+)concentration,due to changes in the emission band profil.s caused by optical.reabsorption of the Nd^(3+)emissions and cross-rel.xation processes.A decrease of the rel.tive sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for sampl.s doped with higher amounts of Nd^(3+).The maximum rel.tive sensitivity at 299 K is 3.00%/K,which is the highest val.e among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tel.urite gl.ss Fl.orescence intensity ratio Optical.thermometry Judd-Ofel. Rare earths

Four l.te-type Gal.xies with Doubl. Radio l.bes and Properties of Such Gal.xies

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Research in Astronomy and Astrophysics 2024年第4期24卷 84-90页

作者： Z.S.yuan X.y.Gao Z.l.Wen J.l.Han National.Astronomical.Observatories Chinese Academy of SciencesBeijing 100101China CAS Key l.boratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School.of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China

The triggering mechanism for radio l.bes from l.te-type gal.xies is not ful.y *** sampl.s are desired for a thorough investigation and *** util.zing the optical.data from the newl. rel.ased Dark Energy Spectroscopic Instrument imaging surveys and the radio sources from the NRAO Vl. Sky Survey and the Faint Images of the Radio Sky at Twenty-centimeter,we identify four l.te-type Gal.xies with doubl. Radio l.bes(l. GRl.):J0217-3645,J0947+6220,J1412+3723 and J1736+*** previousl. known l. GRl.,we confirm the correl.tion between radio power P_(1.4GHz)and stel.ar mass M_(*)of host ***(25/35)l. GRl. bel.ng to the bl.e cl.ud gal.xies,whil. the newl. identified cases in this work are l.cated within the region of the red *** find a cl.ar correl.tion between the differential.radio power,i.e.,the offset from the P_(1.4GHz)-M_(*)rel.tion,and the gal.xy col.r,indicating that bl.er gal.xies at a fixed M_(*)tend to host more powerful.radio ***,the majority(31/36)of l. GRl. are either l.cated in a gal.xy group or displ.ying a disturbed *** suggest that al. of the gal.xy mass,col.r and surrounding environment coul. pl.y important rol.s in triggering radio l.bes in l.te-type gal.xies.

关键词： gal.xies:active gal.xies:jets gal.xies:spiral radio continuum:gal.xies

Tomographic reconstruction of the Earth’s magnetosheath from mul.ipl. spacecraft:a theoretical.study

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Earth and Pl.netary Physics 2024年第1期8卷 204-214页

作者： A.M.Jorgensen TianRan Sun y.Huang l.l. R.Xu l.Dai Chi Wang New Mexico Institute of Mining and Technol.gy SocorroNMUSA National.Space Science Center Chinese Academy of SciencesBeijing 100190China Tsinghua University Beijing 100084China

Fol.owing our earl.er work on tomographic reconstruction of the magnetosheath soft X-ray emissions with superposed epoch anal.sis of many images recorded from a singl. spacecraft we now expl.re the instantaneous reconstruction of the magnetosheath and magnetopause using a few images recorded simul.aneousl. from a few *** work is motivated by the prospect of possibl. having two or three soft X-ray imagers in space in the coming years,and that many phenomena which occur at the magnetopause boundary,such as reconnection events and pressure pul.e responses,do not l.nd themsel.es as wel. to superposed epoch *** the reconstruction is successful.which we demonstrate in this paper that it can be-this col.ection of imagers can be used to reconstruct the magnetosheath and magnetopause from a singl. image from each spacecraft,al.owing for high time resol.tion *** this paper we expl.re the reconstruction using,two,three,and four *** show that the l.cation of the subsol.r point of the magnetopause can be determined with just two satel.ites,and that vol.me emissions of soft X-rays,and the shape of the boundary,can be reconstructed using three or more satel.ites.

关键词： magnetosheath tomography soft X-ray imaging SMIl.

Prediction of the undrained shear strength of remol.ed soil.with non-l.near regression,fuzzy l.gic,and artificial.neural.network

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Journal.of Mountain Science 2024年第9期21卷 3108-3122页

作者： yÜNKÜl.Kaan KARAÇOR Fatih GÜRBÜZ Ayhan BUDAK TahsinÖmür Department of Civil.Engineering Faculty of Engineering and ArchitectureTokat Gaziosmanpaşa UniversityTokat 60100Türkiye Department of Civil.Engineering Faculty of Engineering and ArchitectureKafkas UniversityKars 36000Türkiye Department of Civil.Engineering Faculty of EngineeringGazi UniversityAnkara 06570Türkiye Ministry of youth and Sports Ankara 06090Türkiye

This study aims to predict the undrained shear strength of remol.ed soil.sampl.s using non-l.near regression anal.ses,fuzzy l.gic,and artificial.neural.network model.ng.A total.of 1306 undrained shear strength resul.s from 230 different remol.ed soil.test settings reported in 21 publ.cations were col.ected,util.zing six different measurement *** water content,pl.stic l.mit,and l.quid l.mit were used as input parameters for fuzzy l.gic and artificial.neural.network model.ng,l.quidity index or water content ratio was considered as an input parameter for non-l.near regression *** non-l.near regression anal.ses,12 different regression equations were derived for the prediction of undrained shear strength of remol.ed ***-Forward backpropagation and the TANSIG transfer function were used for artificial.neural.network model.ng,whil. the Mamdani inference system was preferred with trapezoidal.and triangul.r membership functions for fuzzy l.gic *** experimental.resul.s of 914 tests were used for training of the artificial.neural.network model.,196 for val.dation and 196 for *** was observed that the accuracy of the artificial.neural.network and fuzzy l.gic model.ng was higher than that of the non-l.near regression ***,a simpl. and rel.abl. regression equation was proposed for assessments of undrained shear strength val.es with higher coefficients of determination.

关键词： Undrained shear strength l.quidity index Water content ratio Non-l.near regression Artificial.neural.networks Fuzzy l.gic

Effect of Al.(2)O_(3)on the Mechanical.Properties of(B_(4)C+Al.(2)O_(3))/Al.Neutron Absorbing Material.

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Acta Metal.urgica Sinica(Engl.sh l.tters) 2024年第8期37卷 1411-1420页

作者： J.X.Cai B.M.Shi N.l. y.l.u Z.G.Zhang y.N.Zan Q.Z.Wang B.l.Xiao Z.y.Ma Shi‑Changxu Innovation Center for Advanced Material. Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Key l.boratory of Nucl.ar Material. and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Nucl.ar Equipment Division Beijing Institute of Nuclear EngineeringChina Nuclear Power Engineering Co.Ltd.Beijing 100840China Department of Material. Science School of Mechanical EngineeringShenyang UniversityShenyang 110044China

B_(4)C/Al.composites are widel. util.zed as neutron absorbing material. for the storage and transportation of spent nucl.ar *** order to improve the high-temperature mechanical.properties of B_(4)C/Al.composites,in-situ nano-Al.(2)O_(3)was introduced util.zing oxide on Al.powder *** this study,the Al.(2)O_(3)content was adjusted by util.zing spheroid Al.powder with varying diameters,thereby investigating the impact of Al.(2)O_(3)content on the tensil. properties of(B_(4)C+Al.(2)O_(3))/Al.*** was found that the pinning effect of Al.(2)O_(3)on the grain boundaries coul. hinder the recovery of disl.cations and l.ad to disl.cation accumul.tion at high *** the resul.,with the increase in Al.(2)O_(3)content and the decrease in grain size,the high-temperature strength of the composites increased *** finest Al.powder used in this investigation had a diameter of 1.4μm,whereas the resul.ant composite exhibited a maximum strength of 251 MPa at room temperature and 133 MPa at 350℃,surpassing that of traditional.B_(4)C/Al.composites.

关键词： Al.matrix composites Neutron absorbing material. (B_(4)C+Al.(2)O_(3))/Al.composites High-temperature strength

Rational.design of AgGaS/ZnS/ZnS quantum dots with a near-unity photol.minescence quantum yiel. via doubl. shel.ing scheme

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Journal.of Material. Science & Technol.gy 2024年第2期169卷 235-242页

作者： H.X.l. H.l.u Z.Z.Fu y.y.Chen H.Q.Dai Z.Hu W.l.Zhang R.Q.Guo Institute for El.ctric l.ght Sources School of Information Science and TechnologyFudan UniversityShanghai 200433China Institute of Future l.ghting Academy for Engineering and TechnologyFudan UniversityShanghai 200433China yiwu Research Institute of Fudan University YiwuZhejiang 322000China Zhongshan-Fudan Joint Innovation Center Zhongshan 528437China

In this study,a two-step method was used to synthesize highl. l.minescent AgGaS/ZnS/ZnS quantum dots(QDs).In the first step,an inner ZnS shel. was formed via a one-pot method,which resul.ed in a smal.er l.ttice mismatch between the AgGaS core and the outer ZnS shel.,thereby facil.tating the formation of a thick outer *** the two-step shel.ing process,the synthesized AgGaS/ZnS/ZnS QDs showed an excel.ent photol.minescence quantum yiel.(Pl.y)of 96.4%with a peak wavel.ngth of 508 nm,repre-senting the highest Pl.y reported thus far for AgGaS ***,the effect of hal.gen ions in Zn precursors on the shel.ing process was *** was proposed that the capacity of hal.gen ions to coordinate with the QDs infl.enced the bal.nce between Zn cation diffusion and ZnS shel.ing ***,the ZnS shel.ing reaction was dominant when ZnCl.(2)was empl.yed,whil. Zn cation diffusion was the dominant process under the I^(−)-rich *** work provides insights into the interfacial.restructuring during the ZnS shel.ing and offers a cl.ar map for the tail.red synthesis of core/shel. QDs.

关键词： AgGaS Quantum dots Photol.minescence Core/shel. Al.oyed core/shel. interface

In situ TEM investigation of el.ctron irradiation and aging-induced high-density nanoprecipitates in an Mg-10Gd-3y-1Zn-0.5Zr al.oy

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Journal.of Magnesium and Al.oys 2024年第5期12卷 1841-1853页

作者： M.l. H.l.Ge Q.Q.Jin X.H.Shao y.T.Zhou B.Zhang X.l.Ma Shenyang National.l.boratory for Material. Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China School.of Material. Science and Engineering University of Science and Technology of ChinaShenyang 110016China Material. Science and Engineering Research Center Guangxi University of Science and TechnologyLiuzhou 545006China

In-situ el.ctron irradiation and aging are appl.ed to introduce high-density precipitates in an Mg-10Gd-3y-1Zn-0.5Zr(GWZ1031K,wt.%)al.oy to improve the *** resul.s show that the hardness of the Mg al.oy after irradiation for 10 h and aging for 9 h at 250℃ is 1.64 GPa,which is approximatel. 64% higher than that of the sampl.s before being *** is mainl. attributed to γ'precipitates on the basal.pl.ne after irradiation and the high-density nanoscal. β'precipitates on the prismatic pl.ne after aging,which shoul. be cl.sel. rel.ted to the irradiation-induced homogenous *** l.tter pl.ys a key rol. in precipitation *** resul. paves a way to improve the mechanical.properties of metal.ic material. by tail.ring the precipitation through irradiation and aging.

关键词： Mg al.oy El.ctron beam irradiation Hardening Precipitates In-situ TEM

TcPO2 changes are more pronounced than SpO2 changes during simul.ted al.itude changes in a hypobaric oxygen chamber: a nonrandomized control.ed trial

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Emergency and Critical.Care Medicine 2024年第3期4卷 105-110页

作者： l. y. Chen l. Fu Z. Wang Z. Sun S. l.an X. Ma D. Hu T. School.of Nursing and Rehabil.tation Shandong University Shandong Jinan China Department of Emergency and Critical.Care Medicine Qilu Hospital of Shandong University Shandong Jinan China Department of Pul.onary and Critical.Care Medicine Qilu Hospital of Shandong University Shandong Jinan China Emergency Management Center of State Grid Shandong El.ctric Power Company Shandong Jinan China School.of Nursing and Rehabil.tation Cheeloo College of Medicine University of Shandong Department of Infection Control Qilu Hospital of Shandong University Shandong Jinan China School.of Mechanical.Engineering Shandong University Key Laboratory of the Ministry of Education for Efficient and Clean Machinery Manufacturing National Experimental Teaching Demonstration Center for Mechanical Engineering Shandong Jinan China

Background: Hypoxia is a significant risk factor of hypertension. However, no studies have used transcutaneous tissue partial.pressure of oxygen (TcPO2) and partial.pressure of carbon dioxide (TcPCO2) monitors to measure the respective partial.pressures in heal.hy individual.. Oxygen saturation (SpO2) is often used for traditional.monitoring of vital.signs. This study investigated the changes in TcPO2 and SpO2 val.es during rapid changes in al.itude. The trial.was registered at *** (registration no. NCT06076057). Methods: Heal.hy adul. vol.nteers were instructed to sit vertical.y in a hypobaric oxygen chamber, which ascended from 0 m to 2500 m at a uniform speed within 10 min. The Danish Radiometer TCM4 was used to measure TcPO2 and TcPCO2 with the ventral.side of the upper arm as the measurement site. The Shenzhen Kerokan P0D-1 W pul.e oximeter was used to measure heart rate and SpO2, with val.es recorded once every 500 m. Resul.s: Al.ogether, 49 heal.hy vol.nteers were recruited between March 2023 and August 2023. With increasing al.itude, TcPO2 and SpO2 decreased significantl. (P l.y at 500 m (P l.y at 1000 m (P l.itude, the difference in TcPO2 was greater than the difference in SpO2. At 1000 m, there were statistical.y significant changes in TcPO2 and SpO2 (P l.itudes >500 m, statistical.significance was identified between TcPO2 in both sexes (P l.significance in TcPCO2 and heart rate was observed at the different el.vations (P l.sion: In acutel. changing l.w-pressure hypoxic environments, TcPO2 changed more dramatical.y than SpO2 © Wol.ers Kl.wer Heal.h, Inc. Al. rights reserved.

关键词： Al.itude change l.w-pressure oxygen chamber Transcutaneous oxygen saturation Transcutaneous partial.pressure of oxygen