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Finite element analy.is and experimental validation of poly.er-metal contacts in block-on-ring configuration

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Friction 2024年第3期12卷 554-568页

作者： K.y.Eay.l AWWAD Khosro FALLAHNEZHAD B.F.y.USIF Ahmad MOSTAFA Omar ALAJARMEH A.SHALWAN Xuesen ZENG Mechanical Engineering Department Faculty of EngineeringTafila Technical UniversityTafila 66110Jordan Medical Device Research Institute College of Science and EngineeringFlinders UniversitySouth Australia 5042Australia Centre for Future Materials University of Southern QueenslandToowoomba 4350Australia Department of Manufacturing Engineering Technology Public Authority for Applied Education and TrainingKuwait 13092Kuwait

The wear profile analy.is,obtained by.different tribometers,is essential to characterise the wear ***,most of the available methods did not take the stress distribution over the wear profile in consideration,which causes inaccurate *** this study.the wear profile of poly.er–metal contact,obtained by.block-on-ring configuration under dry.sliding conditions,was analy.ed using finite element modelling(FEM)and experimental ***’s wear equation was integrated into a developed FORTRAN-UMESHMOTION code linked with Abaqus software.A vary.ng wear coefficient(k)values covering both running-in and steady.state regions,and a range of applied loads involving both mild and severe wear regions were measured and implemented in the *** FEM was in good agreement with the *** model reproduced the stress distribution profiles under variable testing conditions,while their values were affected by.the sliding direction and maximum wear depth(hmax).The largest area of the wear profile,exposed to the average contact stresses,is defined as the normal *** the critical zones were characterized by.high stress concentrations reaching up to 10 times of that at the normal *** wear profile was mapped to identify.the critical zone where the stress concentration is the key.point in this *** surface features were examined in different regions using scanning electron microscope(SEM).Ultimately.SEM analy.is showed severer damage features in the critical zone than that in the normal zone as proven by.***,the literature data presented and considered the wear features the same at any.point of the wear *** this study.the normal zone was determined at a stress value of about 0.5 MPa,whereas the critical zone was at about 5.5 *** wear behaviour of these two zones showed totally.different features from one another.

关键词： poly.er-to-metal contact block-on-ring wear profile wear model

Dy.amics of Plate Equations with Memory.Driven by.Multiplicative Noise on Bounded Domains

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Journal of Applied Mathematics and Phy.ics 2024年第4期12卷 1492-1521页

作者： Mohamed y. A. Bakhet Abdelmajid Ali Dafallah Jing Wang Qiaozhen Ma Fadlallah Mustafa Mosa Ahmed Eshag Mohamed Paride O. Lolika Makur Mukuac Chinor School of Mathematics University of Juba Juba South Sudan Department of Mathematics Faculty of Petroleum and Hydrology Engineering Alsalam University Almugled Sudan College of Mathematics and Statistics Northwest Normal University Lanzhou China Department of Mathematics and Phy.ics Faculty of Education University of Kassala Kassala Sudan Department of Mathematics School of Education University of Juba Juba South Sudan

This article examines the dy.amics for stochastic plate equations with linear memory.in the case of bounded domain. We investigate the existence of solutions and bounded absorbing set by.using the uniform pullback attractors on the tails estimates, and the asy.ptotic compactness of the random dy.amical sy.tem is proved by.decomposition method, and then we obtain the existence of a random attractor.

关键词： Plate Equations Random Attractors Memory.Term Dy.amical Sy.tems

IMPROVEMENT OF BUBBLE MODEL FOR CAVITATING FLOW SIMULATIONS

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Journal of Hy.rody.amics 2009年第1期21卷 41-46页

作者： TAMURA y. MATSUMOTO y. Computational Science and Engineering Toyo University Kujirai 2100 KawagoeSaitama 350-8585 Japan Mechanical Engineering University of Tokyo Hongo 7-3-1 Bunkyo-kuTokyo 113-8656 Japan

In the present research, a bubble dy.amics based model for cavitating flow simulations is extended to higher void fraction region for wider range of applications. The present bubble model is based on the so-called Ray.eigh-Plesset equation that calculates a temporal bubble radius with the surrounding liquid pressure and is considered to be valid in an area below a certain void fraction. The solution algorithm is modified so that the Ray.eigh-Plesset equation is no more solved once the bubble radius （or void fraction） reaches at a certain value till the liquid pressure recovers above the vapor pressure in order to overcome this problem. This procedure is expected to stabilize the numerical calculation. The results of simple two-dimensional flow field are presented compared with the existing bubble model.

关键词： cavitation model Computational Fluid Dy.amics (CFD) cavitation flow Ray.eigh-Plesset equation

Inclusion of CoTiO_(3) to ameliorate the re/dehy.rogenation properties of the Mg–Na–Al sy.tem

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Journal of Magnesium and Alloy. 2024年第3期12卷 1215-1226页

作者： N.A.Ali N.y.y.snizam N.A.Sazelee Sami-ullah Rather Haizhen Liu M.Ismail Energy.Storage Research Group Faculty of Ocean Engineering TechnologyUniversiti Malaysia Terengganu21030 Kuala NerusTerengganuMalaysia Department of Chemical and Materials Engineering King Abdulaziz UniversityP.O.Box80204Jeddah 21589Saudi Arabia Guangxi Novel Battery.Materials Research Center of Engineering Technology School of Physical Science and TechnologyGuangxi UniversityNanning 530004China State Key.Laboratory.of Featured Metal Materials and Life-Cy.le Safety.for Composite Structures Nanning 530004China

For the first time,the MgH_(2)–NaAlH_(4)(ratio 4:1)destabilized sy.tem with CoTiO_(3) addition has been *** CoTiO_(3)-doped MgH_(2)–NaAlH_(4) sample begins to dehy.rogenate at 130℃,which is declined by.40℃ compared to the undoped MgH_(2)–NaAlH_(4).Moreover,the de/rehy.rogenation kinetics characteristics of the CoTiO_(3)-doped MgH_(2)–NaAlH_(4) were greatly.*** the inclusion of CoTiO_(3),the MgH_(2)–NaAlH_(4) composite absorbed 5.2 wt.%H_(2),higher than undoped MgH_(2)–NaAlH_(4).In the context of dehy.rogenation,the CoTiO_(3)-doped MgH_(2)–NaAlH_(4) sample desorbed 2.6 wt.%H_(2),almost doubled compared to the amount of hy.rogen desorbed from the undoped MgH_(2)–NaAlH_(4) *** activation energy.obtained by.the Kissinger analy.is for MgH_(2) decomposition was significantly.lower by.35.9 kJ/mol than the undoped MgH_(2)–NaAlH_(4) *** reaction mechanism demonstrated that new phases of MgCo and AlTi_(3) were generated in situ during the heating process and are likely.to play.a substantial cataly.ic function and be useful in ameliorating the de/rehy.rogenation properties of the destabilized MgH_(2)–NaAlH_(4) sy.tem with the inclusion of CoTiO_(3).

关键词： Destabilize sy.tem Magnesium hy.ride Sodium alanate Hy.rogen storage Additive.

My.orrhizal fungi mitigate nitrogen losses of an experimental grassland by.facilitating plant uptake and soil microbial immobilization

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Pedosphere 2024年第2期34卷 399-410页

作者： y.ngy.ng JIA Marcel G.A.VAN DER HEIJDEN Alain y.VALZANO-HELD Markus JOCHER Florian WALDER Postdoctoral Mobile Station of Ecology College of Ecology and EnvironmentXinjiang UniversityÜrümqi 830046China Research Group Plant-Soil Interactions AgroscopeZürich 8046Switzerland Research Group Climate and Agriculture AgroscopeZürich 8046Switzerland Department of Plant and Microbial Biology University of ZürichZürich 8008Switzerland Research Group Soil Quality.and Soil Use AgroscopeZürich 8046Switzerland

Nitrogen(N)is one of the most limited nutrients of terrestrial ecosy.tems,whose losses are prevented in tightly.coupled cy.les in finely.tuned *** change-induced N enrichment through atmospheric deposition and application of vast amounts of fertilizer are now challenging the terrestrial N *** my.orrhizal fungi(AMF)are known drivers of plant-soil nutrient fluxes,but a comprehensive assessment of AMF involvement in N cy.ling under global change is still ***,we simulated N enrichment by.fertilization(low/high)in experimental grassland microcosms under greenhouse conditions in the presence or absence of AMF and continuously.monitored different N pathway. over nine *** found that high N enrichment by.fertilization decreased the relative abundance of legumes and the plant species dominating the plant community.changed from grasses to forbs in the presence of AMF,based on aboveground *** presence of AMF alway. maintained plant N:phosphorus(P)ratios between 14 and 16,no matter how the soil N availability.*** in plant N:P ratios due to the increased plant N and P uptake might thus be a primary.pathway.of AMF altering plant community.***,we constructed a comprehensive picture of AMF’s role in N cy.ling,highlighting that AMF reduced N losses primarily.by.mitigating N leaching,while N_(2)O emissions play.d a marginal *** my.orrhizal fungi reduced N_(2)O emissions directly.through the promotion of N_(2)O-consuming *** underly.ng mechanism for reducing N leaching is mainly.the AMF-mediated improved nutrient uptake and AMF-associated microbial *** results indicate that sy.ergies between AMF and other soil microorganisms cannot be ignored in N cy.ling and that the integral role of AMF in N cy.ling terrestrial ecosy.tems can buffer the upcoming global changes.

关键词： N cy.ling N enrichment N uptake N:P ratio plant community.structure sy.biotic soil fungi

Annotated survey.and perspectives on rail transport energy.sy.tem RAMS evaluation technology

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Green Energy.and Intelligent Transportation 2024年第3期3卷 75-90页

作者： Ruifeng Shi Lingzhi Zhang Feng Lin Jin Ning Limin Jia Kwang y.Lee School of Control and Computer Engineering North China Electric Power UniversityBeijing 102206China China Institute of Energy.and Transportation Integrated Development Beijing 102206China State Key.Lab of Rail Traffic Control&Safety Beijing Jiaotong UniversityBeijing 100044China Department of Electrical and Computer Engineering Baylor UniversityWacoTX 76798USA

The rail transit sy.tem play. a crucial role in modern *** the increasing demand for clean and green energy.in the transport sector,its energy.sy.tem is expected to achieve low-carbon and highly.efficient energy.utilization in rail ***,the gradual development of the rail transport energy.sy.tem has led to an increase in its complexity.and the rising difficulty.of sy.tem assessment has faced the limitations of traditional assessment ***,it is essential to develop effective assessment *** paper begins by.providing a sy.tematic review of the development status of Reliability.Availability.Maintainability.and Safety.RAMS)assessment and analy.ing the shortcomings of traditional RAMS assessment technology.in the context of rail transit energy.***,based on the four fundamental properties of RAMS,it summarizes the current state of key.assessment technologies in the field of rail ***,the paper delves into the challenges and potential solutions concerning the implementation of RAMS assessment technology.for rail transit energy.***,the paper offers an outlook on the future development of RAMS assessment for rail transport energy.*** comprehensively.analy.ing these aspects,the paper aims to contribute valuable insights into optimizing the rail transit energy.sy.tem,promoting its sustainable and efficient operation in the context of clean and green energy.utilization.

关键词： Integration of energy.and transportation RAMS evaluation Rail transit energy.sy.tem

Association between the Different Phenoty.es of Poly.y.tic Ovary.Sy.drome and the Outcome in in Vitro Fertilization at Human Reproductive Center Paul et Chantal Biy.-y.oundé

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Open Journal of Obstetrics and Gy.ecology 2024年第1期14卷 18-28页

作者： Ngono Akam Vanina Ngah Minala Belinga Etienne Belinga Etienne Mpono Pascale Ny.da Serges Onana y. Kasia Cho Josely.e Kasia Florence Adjessa Abega Kasia Jean Marie Gy.aecological Endoscopic Surgery.and Human Reproductive Teaching Hospital Yaoundé Cameroon Department of Gy.ecology.and Obstetrics Faculty of Medicine and Biomedical Sciences University of Yaoundé 1 Yaoundé Cameroon

Background: In Vitro Fertilization/Intracy.oplasmic Sperm Injection (IVF/ICSI) represents the final step in the management of Poly.y.tic Ovarian Sy.drome (PCOS). Our objective was to study.the association between PCOS phenoty.es and IVF/ICSI results in women admitted to Gy.aecological Endoscopic Surgery.and Human Reproductive Teaching Hospital (CHRACERH). Material and Method: We carried out a cohort study.with historical-prospective data collection over a period of seven y.ars (January.2016 to March 2023) at Chracerh. PCOS patients were subdivided into 4 subgroups A, B, C and D. Results: We recruited 128 patients including 64 PCOS patients divided into four phenoty.es and 64 non-PCOS patients constituting the control group. Phenoty.e D without hy.erandrogenism had used the lowest dose of gonadotropins, i.e. 1939.7 ± 454.3 IU, and had produced a greater quantity.of estradiol on the day.ovulation was triggered (6529.8 ± 4324.8 ng/ml). The average number of punctured follicles and mature oocy.es were higher in the phenoty.e D group. Ovarian hy.erstimulation sy.drome (OHSS) occurred mainly.in phenoty.e D (3/35), with an estimated prevalence of 2.3%. The fertilization rate seemed lower in the hy.erandrogenic phenoty.es A, B, C compared to the group without hy.erandrogenism without significant difference (p = 0.461). The biological pregnancy.rate and live birth rate were comparable between the different groups. Conclusion: Phenoty.e D used less dose of gonadotropins. Biological pregnancy.and live birth rates were comparable between the different phenoty.es.

关键词： Phenoty.e Poly.y.tic Ovarian Sy.drome IVF/ICSI Prognosis CHRACERH

Late corneal ectasia after penetrating and deep anterior lamellar keratoplasty.for keratoconus

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International Journal of Ophthalmology.English edition) 2024年第10期17卷 1828-1836页

作者： Bora y.ksel Arife Esra Kocakay. Tuncay.Küsbeci Fatih Gümüş Department of Ophthalmology University of Health SciencesIzmir Bozyaka Education and Research HospitalIzmir 35110Türkiye

AIM:To investigate tomographic features of late corneal ectasia after keratoplasty.for keratoconus and compare penetrating keratoplasty.PK)and deep anterior lamellar keratoplasty.DALK)in terms of incidence,time of onset and risk factors of corneal ***:Sixty.ey.s with PK and 30 ey.s with DALK operated between 1999 and 2021 were *** Pentacam scans were evaluated together with vision and previous *** outcome measures were vision,K values,apparent thinning on graft-host cornea and the difference between opposing quadrants in the thinnest point *** segment optic coherence tomography.was performed for further ***:Mean follow-up was 127.2mo(24–282mo)in PK,and 64.3mo(24–144mo)in DALK.K max was higher in DALK(60.6 vs 56.7 D,P=0.012).Inferior recipient was thinner(595.9μm)in PK than DALK(662.2μm,P=0.021),due to longer *** corneal ectasia rate was 20.0%within *** rate was the same(6.7%)in DALK 2/30 and in PK 4/60 in 10y.and 13.3%in 12y.4/30 and 8/60,respectively..It increased to 23.3%(14/60)in PK over *** ectasia was not seen before 7y.in PK,it could be seen in DALK starting from the 5^(th) *** intervals between keratoplasty.and ectasia were 144.5mo in PK and 99mo in *** recipient was significantly.thinner in 18 ey.s with ectasia(502.7μm)compared to 76 non-ectasia(649.1μm,P=0.000).Inferior graft was thinner(561.0 vs 620.4μm,P=0.006),K max(63.3 vs 56.5 D,P=0.000),and anterior elevation was higher in ectasia(89.1 vs 48.6μm,P=0.002).Accelerated crosslinking was performed on 5 ***:Inferior-superior recipient and inferior graft thinning on tomography.with high K max and anterior elevation emerge as the most reliable criteria for the diagnosis of late *** incidence of corneal ectasia increases with the time.

关键词： keratoconus penetrating keratoplasty deep anterior lamellar keratoplasty corneal ectasia

Tailored architecture of composite electroly.e for all-solid-state sodium batteries with superior rate performance and cy.le life

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Nano Research 2024年第5期17卷 4171-4180页

作者： Xiang Guan Zhenhua Jian Xingan Liao Wenchao Liao y.nfei Huang Dazhu Chen Robert K.y.Li Chen Liu Shenzhen Key.Laboratory.of Poly.er Science and Technology Guangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhen 518055China Department of Materials Science and Engineering City University of Hong KongHong KongChina

Seeking for composite electroly.es reinforced all-solid-state sodium ion batteries with superior long lifespan and rate performance remains a great ***,a unique strategy.to tailor the architecture of composite electroly.e via inserting poly.er chains into a small quantity.of sulfate sodium grafted C_(48)0H_(28)O_(32)Zr_(6)(UIOSNa)is *** intimate contact between poly.er segments and UIOSNa with limited pore size facilitates the anion immobilization of sodium salts and reduction of poly.er cry.tallinity.thereby.providing rapid ion conduction and reducing the adverse effect caused by.the immigration of *** tNa+grafting of-SO_(3)Na groups on fillers allows the free movement of more sodium ions to further improve and ionic ***,even with the low content of UIOSNa fillers,a high ionic conductivity.of 6.62×10^(-4) S·cm^(-1) at 60℃ and a transference number of 0.67 for the special designed composite electroly.e are *** assembled all-solid-state sodium cell exhibits a remarkable rate performance for 500 cy.les with 95.96%capacity.retention at a high current rate of 4 *** corresponding pouch cell can stably.work for 1000 cy.les with 97.03%capacity.retention at 1 C,which is superior to most of the reported composite electroly.es in the literature.

关键词： solid state sodium battery composite electroly.e rate performance cy.le life