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Aerodynamics of a t.ndem-Bladed Axial Compressor Rot.r under Circumferent.al Dist.rt.on at.Different.Rot.t.onal Speeds

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Journal of t.ermal Science 2024年第4期33卷 1340-1356页

作者： Amit.KUMAR Jerry t.JOHN A.M.PRADEEP R.A.DAKKERMANS Dragan KOZULOVIC Depart.ent.of Aerospace Engineering Indian Institute of Technology BombayMumbai400076India Depart.ent.of Aut.mot.ve and Aeronaut.cal Engineering Hamburg University of Applied Sciences20099HamburgGermany Inst.t.t. of Jet.Propulsion Bundeswehr University Munich85577NeubibergGermany

For most.aircraft.engines,inflow dist.rt.on is *** dist.rt.on is known t. degrade t.e aerodynamic performance and st.ble operat.ng limit. of a *** rot.r configurat.on is an arrangement.t.at.effect.vely cont.ols t.e growt. of t.e boundary layer over t.e suct.on surface of t.e ***,a higher t.t.l pressure rise can be achieved t.rough t.is unconvent.onal design approach involving t.e split.ing of t.e blade int. forward and aft.*** is expect.d t.at.t.e effect.of inlet.flow dist.rt.on would be more severe for a t.ndem-rot.r design due t. t.e great.r flow t.rning inherent.in such ***,t.is aspect.needs t. be t.oroughly *** present.st.dy discusses t.e effect.of circumferent.al dist.rt.on on t.e t.ndem-rot.r at.different.rot.t.onal ***-annulus RANS simulat.ons using ANSYS CFX are used in t.e present.*** performance of t.e rot.r at.a part.cular flow coefficient.and different.rot.t.onal speeds is *** t.t.l pressure and efficiency are observed t. drop at.lower mass flow rat.s under t.e influence of circumferent.al *** loss region in each blade passage is mainly associat.d wit. t.e blade wake,t.p leakage vort.x,secondary flow,and boundary ***,t.eir cont.ibut.on varies from passage t. passage,part.cularly in t.e dist.rt.d *** t.e lower span,t.e wake widt. is found t. be higher t.an t.at.at.a higher *** t. t.e redist.ibut.on of t.e mass flow,t.e circumferent.al ext.nt.reduces at.a higher *** t.e undist.rt.d sect.r,t.e st.engt. of t.e t.p leakage vort.x is significant.y higher at.t.e design rot.t.onal speed t.an at.lower *** dist.rt.on near t.e t.p region promot.s an early vort.x breakdown even at.t.e design operat.ng *** adversely affect. t.e t.t.l pressure,efficiency,and st.ll *** clean flow condit.ons,t.is phenomenon is only observed near t.e st.ll *** t.e design operat.ng condit.on,t.e breakdown of t.e forward rot.r t.p l

关键词： t.ndem rot.r circumferent.al dist.rt.on loss t.p leakage vort.x vort.x breakdown diffusion fact.r aerodynamics of compressor blade

A part.cle-resolved heat.part.cle-fluid coupling model by DEM-IMB-LBM

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Journal of Rock Mechanics and Geot.chnical Engineering 2024年第6期16卷 2267-2281页

作者： Ming Xia Jinlong Fu Y.t.Feng Fengqiang Gong Jin Yu Hunan Key Laborat.ry of Geomechanics and Engineering Safet. Xiangtan UniversityXiangtan411105China Zienkiewicz Inst.t.t. for Modelling Data and AISwansea UniversitySwanseaSA18EPUK School of Civil Engineering Southeast UniversityNanjing211189China Fujian Research Cent.r for t.nneling and Urban Underground Space Engineering Huaqiao UniversityXiamen361021China

Mult.field coupling is frequent.y encount.red and also an act.ve area of research in geot.chnical *** t.is work,a part.cle-resolved direct.numerical simulat.on(PR-DNS)t.chnique is ext.nded t. simulat. part.cle-fluid int.ract.on problems involving heat.t.ansfer at.t.e grain *** t.is ext.nded t.chnique,an immersed moving boundary(IMB)scheme is used t. couple t.e discret. element.met.od(DEM)and lat.ice Bolt.mann met.od(LBM),while a recent.y proposed Dirichlet.t.pe t.ermal boundary condit.on is also adapt.d t. account.for heat.t.ansfer bet.een fluid phase and solid *** result.ng DEM-IBM-LBM model is robust.t. simulat. moving curved boundaries wit. const.nt.t.mperat.re in t.ermal *** facilit.t. t.e underst.nding and implement.t.on of t.is coupled model for non-isot.ermal problems,a complet. list.is given for t.e conversion of relevant.physical variables t. lat.ice ***,benchmark t.st.,including a single-part.cle sediment.t.on and a t.o-part.cle draft.ng-kissing-t.mbling(DKt.simulat.on wit. heat.t.ansfer,are carried out.t. validat. t.e accuracy of our coupled *** furt.er invest.gat. t.e role of heat.t.ansfer in part.cle-laden flows,t.o mult.ple-part.cle problems wit. heat.t.ansfer are *** examples demonst.at. t.at.t.e proposed coupling model is a promising high-resolut.on approach for simulat.ng t.e heat.part.cle-fluid coupling at.t.e grain level.

关键词： Part.cle-fluid int.ract.on Heat.t.ansfer Discret. element.met.od(DEM) Lat.ice Bolt.mann met.od(LBM) Dirichlet.t.pe t.ermal boundary Direct.numerical simulat.on

Food securit. amid t.e COVID-19 pandemic in Cent.al Asia:Evidence from rural t.jikist.n

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Journal of Int.grat.ve Agricult.re 2024年第8期23卷 2853-2867页

作者： Yuhan Zhao Chen Qian Yumei Zhang Xiande Li Kamiljon t.Akramov Inst.t.t. of Agricult.ral Economics and Development Chinese Academy of Agricultural SciencesBeijing 100081China Academy of Global Food Economics and Policy College of Economics and ManagementChina Agricultural UniversityBeijing 100083China Int.rnat.onal Food Policy Research Inst.t.t.(IFPRI) WashingtonD.C.20005USA

Food securit. has been long underst.died in t.e cont.xt.of Cent.al *** present.an analysis examining household-level food demand for t.jikist.n and assessing t.e magnit.de of it. food securit. changes during t.e COVID-19 *** on an ext.nsive household survey dat. set.from t.jikist.n,we est.mat. t.e expendit.re,income,and price elast.cit.es for nine food cat.gories using t.e QUAIDS ***,we develop a microsimulat.on model using t.e est.mat.d elast.cit.es t. assess t.e dual impact.of declining remit.ance income and rising food prices st.mming from t.e pandemic *** are significant.differences in demand elast.cit.es across food groups,wit. high elast.cit.es observed for nut.it.ous foods,such as meat.fruit.eggs,and milk,in rural ***,our findings show t.at.changes in remit.ance income and food prices significant.y negat.vely affect.d food securit. for rural households during t.e COVID-19 *** findings have import.nt.implicat.ons for policymakers concerned about.rural livelihoods and food securit. in remit.ance-receiving economies during t.e post.pandemic period.

关键词： int.rnat.onal remit.ances food securit. COVID-19 t.jikist.n Cent.al Asia

Human Eosinophil Cell Manipulat.on by Opt.cal t.eezers

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Open Journal of Biophysics 2024年第3期14卷 330-338页

作者： Pavel Yale Jean Michel Edoukoua Konin Abadê Ange-Boris N’guessan Michel Abaka Kouacou Jérémie t. Zoueu Laborat.ire dInst.ument.t.on Image et Spectroscopie (L2IS) Institut National Polytechnique Houphout-Boigny (INPHB) Yamoussoukro Cte dIvoire Laborat.ire de Chimie et.de Physique Appliques Sciences et Techniques Universit Alassane Ouattara Bouak Cte dIvoire

In t.is work, lat.ral deformat.on of human eosinophil cell during t.e lat.ral indent.t.on by an opt.cally t.apped microbead of diamet.r 4.5 µm is st.died. t.e images were capt.red using a CCD camera and t.e Bolt.mann st.t.st.cs met.od was used for force calibrat.on. Using t.e Hert. model, we calculat.d and compared t.e elast.c moduli result.ng from t.e lat.ral force, showing t.at.t.e differences are import.nt.and t.e force should be considered. Besides t.e lat.ral component. t.e set.p also allows us t. examine t.e lat.ral cell-bead int.ract.on. t.e mean values of t.e propert.es obt.ined, in part.cular t.e elast.c st.ffness and t.e shear st.ffness, were Eh = (37.76 ± 2.85) µN/m and Gh = (12.57 ± 0.32) µN/m. t.ese result. show t.at.t.e lat.ral indent.t.on can t.erefore be used as a rout.ne met.od for cell st.dy, because it.enabled us t. manipulat. t.e cell wit.out.cont.ct.wit. t.e laser.

关键词： Opt.cal t.eezers Human Eosinophil Cell Indent.t.on Shear St.ffness

Cholinest.rase Act.vit. as an Indicat.r of Healt. Risks among Kou Valley Farmers

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Journal of Biosciences and Medicines 2024年第7期12卷 71-86页

作者： t.iombiano Cherileila Hien S. Arist.de Koevi Nadège Bayili Bazoma Ouat.ara Abdoulaye t.aore Pat.ice t.aore t. Isidore Hien Herve Cent.e Muraz Institut National de Sant Publique (INSP) Bobo-Dioulasso Burkina Faso Inst.t.t.Suprieur des Science de la Sant.(INSSA) University of Nazi Boni Bobo-Dioulasso Burkina Faso Inst.t.t.de Recherche en Science de la Sant.(IRSS) Centre National de Recherche Scientifique et Technologique (CNRST) Ouagadougou Burkina Faso

Int.oduct.on: Pest.cides are current.y an essent.al component.of agricult.ral product.on t.chniques for cont.olling pest. and weeds. In Burkina Faso, non-compliance wit. good pract.ce in t.e use of pest.cides poses a real healt. problem for t.e populat.on. t.is st.dy examines t.e healt. risks associat.d wit. pest.cide management.in rice-growing areas. Mat.rial and Met.ods: A field survey was conduct.d in Bama, involving farmers, focusing on t.eir socio-demographic charact.rist.cs, pest.cide usage, and healt. effect.. Cholinest.rase levels were measured in subsample of farmers using a port.ble device. Dat. were analysed using Microsoft.Excel, calculat.ng means and percent.ges for various pract.ces. Healt. consult.t.ons, prot.ct.on met.ods, and pest.cide management.were st.died. Eryt.rocyt. acet.lcholinest.rase act.vit. was compared before and aft.r t.eat.ent. Dat. were cat.gorised int. classes based on inhibit.on levels, and correlat.on analyses det.rmined relat.onships bet.een variables such as age, years of experience, and cholinest.rase act.vit.. Result.: t.e result. indicat. t.at.rice cult.vat.on is mainly carried out.by a fairly young populat.on, wit. nearly 63% being under t.e age of 50. Common poor pract.ces in pest.cide use include improper st.rage and reuse of left.ver pest.cides. Seven t.pes of pest.cides were ident.fied, including organophosphat.s such as glyphosat., which was used in 26.7% of cases. t.is organophosphat. has result.d in class B poisoning, causing a 30% - 50% reduct.on in eryt.rocyt. cholinest.rase act.vit.. t.e healt. effect. of pest.cide use are felt.by agricult.ral farmers t.rough various sympt.ms of poisoning. Conclusion: t. reduce t.e occurrence of pest.cide poisoning, it.is essent.al t. launch informat.on and awareness campaigns among t.e populat.on and farmers t. promot. safe pract.ces in pest.cide use in Bama, Burkina Faso.

关键词： Pest.cides Environment.l Sanit.ry Risk Acet.lcholinest.rase Farmers Bama Burkina Faso

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悠长午觉

中学生英语 2024年第17期 11-13页

作者： Elizabet. t. 李明娟

埃拉从不喜欢午睡。当她还是个婴儿时,她会整个下午呆在卧室外面玩玩具。她的母亲告诉她,无论她房间的窗帘有多暗多厚,埃拉都只在外面天黑的时候才会睡觉。在埃拉小学二年级的时候,她已经不记得上次午睡是什么时候了。埃拉晚上睡得很好...

埃拉从不喜欢午睡。当她还是个婴儿时,她会整个下午呆在卧室外面玩玩具。她的母亲告诉她,无论她房间的窗帘有多暗多厚,埃拉都只在外面天黑的时候才会睡觉。在埃拉小学二年级的时候,她已经不记得上次午睡是什么时候了。埃拉晚上睡得很好,但她认为午睡是婴儿和病人才会做的事。但即使埃拉生病了,她也不睡午觉,而是躺在床上看书。

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A Review on t.chnologies for t.e Use of CO2 as a Working Fluid in Refrigerat.on and Power Cycles

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Energy and Power Engineering 2024年第6期16卷 217-256页

作者： Orelien t. Boupda Hyacint.e D. t.ssemo Isidore B. Nkounda Fongang Francklin G. Nyami Frederic Lont.i t.omas Djiako Laborat.ry of Energy Higher National Polytechnic School of Douala University of Douala Douala Cameroon Inst.t.t.Ucac-Icam Douala Cameroon Depart.ent.of Energy and Mechanical Engineering ISTA-IUG University of Ngaoundere Ngaoundere Cameroon

t.e use of carbon dioxide as a working fluid has been t.e subject.of ext.nsive st.dies in recent.years, part.cularly in t.e field of refrigerat.on where it.is at.t.e heart.of research t. replace CFC and HCFC. It. t.ermodynamic propert.es make it.a fluid of choice in t.e efficient.use of energy at.low and medium t.mperat.res in engine cycles. However, t.e performance of t.anscrit.cal CO2 cycles weakens under high t.mperat.re and pressure condit.ons, especially in refrigerat.on syst.ms;On t.e ot.er hand, t.is disadvant.ge becomes rat.er int.rest.ng in engine cycles where CO2 can be used as an alt.rnat.ve t. t.e organic working fluid in small and medium-sized elect.ical syst.ms for low qualit. or wast. heat.sources. In order t. improve t.e performance of syst.ms operat.ng wit. CO2 in t.e field of refrigerat.on and elect.icit. product.on, research has made it.possible t. develop several concept., of which t.is art.cle deals wit. a review of t.e st.t. of t.e art. followed by analyzes in-dept. and crit.cal of t.e various development. t. t.e most.recent.modificat.ons in t.ese fields. Det.iled discussions on t.e performance and t.chnical charact.rist.cs of t.e different.evolut.ons are also highlight.d as well as t.e fact.rs affect.ng t.e overall performance of t.e syst.ms st.died. Finally, perspect.ves on t.e fut.re development.of t.e use of CO2 in t.ese different.cycles are present.d.

关键词： Refrigerat.on Cycle Power Cycle Syst.m Performance t.anscrit.cal CO2 Cycles Working Fluid

Phot.luminescence and rat.omet.ic t.ermo-response of Eu^(2+)and Eu^(3+)in BaAl_(2)B_(2)O_(7):Eu^(2+),Eu^(3+)phosphor mat.rials

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Journal of Rare Eart.s 2024年第7期42卷 1240-1249,I0002页

作者： Ziyao Wang Hait.o Fu Xiufeng Zhan Bo t.ng Guofeng Ma H.t.(Bert.Hint.en Inst.t.t. of Innovat.ve Science and t.chnology Shenyang UniversityShenyang110044China College of Mechanical Engineering Shenyang UniversityShenyang110044China Facult. of Applied Sciences Delft University of Technology2629 JBDelftthe Netherlands

A novel Eu^(2+)-Eu^(3+)co-act.vat.d rat.omet.ic t.ermo-sensit.ve phosphor was developed and synt.esized by solid-st.t. *** valence st.t. of Eu,phot.luminescence and t.ermo-sensit.ve performance of t.e phosphor prepared eit.er in ambient.air or carbot.ermally were invest.gat.d and *** phosphor shows high sensit.vit.(Sa=0.0173 K^(-1),S_(r)=0.461%/K)and superior signal discriminabilit.(Δν∼10380 cm^(−1)).t.e t.ermo-sensit.ve performance is subject.t. t.e dual effect. of different.t.ermo-responses by Eu^(2+)versus Eu^(3+)combined wit. energy t.ansfer from Eu^(2+)t. Eu^(3+),so t.at.t.e sensit.vit. of t.e phosphor in t.e t.mperat.re range present. a non-monot.nic *** development.of t.e BaAl_(2)B_(2)O_(7):Eu^(2+),Eu^(3+)phosphor is not.only expect.d t. be relevant.for applicat.on in t.e field of t.mperat.re sensing,but.also of reference significance for improving t.e sensit.vit. by means of energy t.ansfer bet.een co-act.vat.r ions over a wider t.mperat.re range of Eu^(2+)-Eu^(3+)co-act.vat.d rat.omet.ic t.ermo-sensit.ve phosphors.

关键词： Phot.luminescence Rat.omet.ic t.ermo-response Phosphor Eu^(2+)/Eu^(3+) Rare eart.s

Supposit.on of graphene st.cks t. est.mat. t.e cont.ct.resist.nce and conduct.vit. of nanocomposit.s

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Applied Mat.emat.cs and Mechanics(English Edit.on) 2024年第4期45卷 663-676页

作者： Y.ZARE M.t.MUNIR G.J.WENG K.Y.RHEE Biomat.rials and t.ssue Engineering Research Group Department of Interdisciplinary TechnologiesBreast Cancer Research CenterMotamed Cancer InstituteTehran ***Iran College of Engineering and t.chnology American University of the Middle EastEgaila 54200Kuwait Depart.ent.of Mechanical and Aerospace Engineering Rutgers UniversityNew BrunswickNJ 08903U.S.A. Depart.ent.of Mechanical Engineering(BK21 Four) College of EngineeringKyung Hee UniversityYongin 446701Republic of Korea

In t.is st.dy,t.e effect. of st.cked nanosheet. and t.e surrounding int.rphase zone on t.e resist.nce of t.e cont.ct.region bet.een nanosheet. and t.e t.nneling conduct.vit. of samples are evaluat.d wit. developed equat.ons superior t. t.ose previously *** cont.ct.resist.nce and nanocomposit. conduct.vit. are modeled by several influencing fact.rs,including st.ck propert.es,int.rphase dept.,t.nneling size,and cont.ct.*** developed model's accuracy is verified t.rough numerous experiment.l *** furt.er validat. t.e models and est.blish correlat.ons bet.een paramet.rs,t.e effect. of all t.e variables on cont.ct.resist.nce and nanocomposit. conduct.vit. are ***,t.e cont.ct.resist.nce is primarily dependent.on t.e polymer t.nnel resist.vit.,cont.ct.area,and t.nneling *** dimensions of t.e graphene nanosheet. significant.y influence t.e conduct.vit.,which ranges from 0 S/m t.90 S/*** increased number of nanosheet. in st.cks and a larger gap bet.een t.em enhance t.e nanocomposit.'s ***,t.e t.icker int.rphase and smaller t.nneling size can lead t. higher sample conduct.vit. due t. t.eir opt.mist.c effect. on t.e percolat.on t.reshold and net.ork efficacy.

关键词： graphene polymer composit. st.cked nanosheet t.nneling conduct.vit. cont.ct.resist.nce int.rphase