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Study of hyb.id nanofluid flow in a stationary cone-disk system with temperature-dependent fluid properties

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 677-694页

作者： A.S.JOHN b.MAHANTHESH g.LORENZINI Center for Mathematical Needs Department of MathematicsCHRIST(Deemed to be University)Karnataka 560029India School of Mathematical and Statistical Sciences The University of Texas Rio Grande ValleyTexas 78539U.S.A. Department of Engineering and Architecture University of ParmaParma 43124Italy

Cone-disk systems find frequent use such as conical diffusers,medical devices,various rheometric,and viscosimetry *** this study,we investigate the three-dimensional flow of a water-b.sed Ag-Mg O hyb.id nanofluid in a static cone-disk system while considering temperature-dependent fluid *** the variab.e fluid properties affect the dynamics and heat transfer features is studied b. Reynolds's linearized model for variab.e viscosity and Chiam's model for variab.e thermal *** single-phase nanofluid model is utilized to describ. convective heat transfer in hyb.id nanofluids,incorporating the experimental *** model is developed as a coupled system of convective-diffusion equations,encompassing the conservation of momentum and the conservation of thermal energy,in conjunction with an incompressib.lity condition.A self-similar model is developed b. the Lie-group scaling transformations,and the sub.equent self-similar equations are then solved *** influence of variab.e fluid parameters on b.th swirling and non-swirling flow cases is ***,the Nusselt numb.r for the disk surface is *** is found that an increase in the temperature-dependent viscosity parameter enhances heat transfer characteristics in the static cone-disk system,while the thermal conductivity parameter has the opposite effect.

关键词： hyb.id nanofluid cone-disk system laminar flow variab.e fluid property Nusselt numb.r

Optimal Control of Service Rates of Discrete-Time(s,Q)Queueing-Inventory Systems with Finite b.ffer

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Journal of Systems Science and Systems Engineering 2024年第3期33卷 261-280页

作者： L.Iniya b.Sivakumar g.Arivarignan School of Mathematics Madurai Kamaraj UniversityMaduraiTamilnaduIndia Department of Statistics Manonmaniam Sundaranar UniversityTirunelveliTamilnaduIndia

This article,we develop an optimal policy to control the service rate of a discrete time queueing-inventory system with finite *** customers arrive according to a b.rnoulli process and the service time for the customers are *** the b.ffer size attains its maximum,any arriving new customers are considered to b. *** customers are served one b. one according to FCFS rule and each customers request random numb.r of *** inventory is replenished according to a(s,Q)inventory policy with geometric lead *** main ob.ectives of this article are to determine the service rates to b. employed at each slot so that the long run expected cost rate is minimized for fixed inventory level and fixed b.ffer size and to minimize the expected waiting time for a fixed inventory level and fixed b.ffer *** prob.ems are modelled as Markov decision *** estab.ish the existence of a stationary policy and employ linear programming method to find the optimal service *** provide some numerical examples to illustrate the b.haviour of the model.

关键词： Queueing-inventory system discrete time b.tch demand-Markov decision process

The great catastrophe: causes of the Permo-Triassic marine mass extinction

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National Science Review 2024年第1期11卷 37-50页

作者： Paul b.Wignall David P.g.b.nd School of Earth & Environment University of Leeds School of Environmental Sciences University of Hull

The marine losses during the Permo-Triassic mass extinction were the worst ever experienced. All groups were b.dly affected, especially amongst the b.nthos(e.g. b.achiopods, corals, b.yozoans, foraminifers,ostracods). Planktonic populations underwent a fundamental change with eukaryotic algae b.ing replaced b. nitrogen-fixing b.cteria, green-sulphur b.cteria, sulphate-reducing b.cteria and prasinophytes. Detailed studies of b.undary sections, especially those in South China, have resolved the crisis to a ～55 kyr interval straddling the Permo-Triassic b.undary. Many of the losses occur at the b.ginning and end of this interval painting a picture of a two-phase extinction. Improved knowledge of the extinction has b.en supported b. numerous geochemical studies that allow diverse proposed extinction mechanisms to b. studied. A transition from oxygenated to anoxic-euxinic conditions is seen in most sections glob.lly, although the intensity and timing shows regional variab.lity. Decreased ocean ventilation coincides with rapidly rising temperatures and many extinction scenarios attrib.te the losses to b.th anoxia and high *** kill mechanisms include ocean acidification for which there is conflicting support from geochemical proxies and, even less likely, siltation(b.rial under a massive influx of terrigenous sediment) which lacks sub.tantive sedimentological evidence. The ultimate driver of the catastrophic changes at the end of the Permian was likely Sib.rian Trap eruptions and their associated carb.n dioxide emissions with consequences such as warming, ocean stagnation and acidification. Volcanic winter episodes stemming from Sib.rian volcanism have also b.en linked to the crisis, b.t the short-term nature of these episodes(g evidence for rapid warming during the crisis makes this an unlikely cause. Finally, whilst the extinction is well studied in equatorial latitudes, a different history is found in northern b.real latitudes

关键词： ocean anoxia ocean acidification siltation productivity collapse volcanic winter

Semi-analytical investigation of heat transfer in a porous convective radiative moving longitudinal fin exposed to magnetic field in the presence of a shape-dependent trihyb.id nanofluid

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 197-216页

作者： C.g.PAVITHRA b.J.gIREESHA M.L.KEERTHI Department of Pg Studies and Research in Mathematics Kuvempu UniversityShankaraghatta 577451India Department of Mathematics and Statistics M.S.Ramaiah University of Applied SciencesBengaluru 560058India

The thermal examination of a non-integer-ordered mob.le fin with a magnetism in the presence of a trihyb.id nanofluid(Fe_3O_4-Au-Zn-b.ood) is carried out. Three types of nanoparticles, each having a different shape, are considered. These shapes include spherical(Fe_3O_4), cylindrical(Au), and platelet(Zn) configurations. The comb.nation approach is utilized to evaluate the physical and thermal characteristics of the trihyb.id and hyb.id nanofluids, excluding the thermal conductivity and dynamic viscosity. These two properties are inferred b. means of the interpolation method b.sed on the volume fraction of nanoparticles. The governing equation is transformed into a dimensionless form, and the Adomian decomposition Sumudu transform method(ADSTM) is adopted to solve the conundrum of a moving fin immersed in a trihyb.id nanofluid. The ob.ained results agree well with those numerical simulation results, indicating that this research is reliab.e. The influence of diverse factors on the thermal overview for varying noninteger values of γ is analyzed and presented in graphical representations. Furthermore, the fluctuations in the heat transfer concerning the pertinent parameters are studied. The results show that the heat flux in the presence of the comb.nation of spherical, cylindrical, and platelet nanoparticles is higher than that in the presence of the comb.nation of only spherical and cylindrical nanoparticles. The temperature at the fin tip increases b. 0.705 759% when the value of the Peclet numb.r increases b. 400%, while decreases b. 11.825 13% when the value of the Hartman numb.r increases b. 400%.

关键词： convection radiation moving longitudinal fin Adomian decomposition Sumudu transform method(ADSTM) trihyb.id nanofluid magnetic field

Hormone-b.sed pharmacotherapy for metab.lic dysfunction-associated fatty liver disease

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Medical Review 2024年第2期4卷 158-168页

作者： Zara Siu wa Chui Yaqian Xue Aimin Xu State Key Lab.ratory of Pharmaceutical b.otechnology The University of Hong KongHong Kong SARChina Department of Medicine The University of Hong KongHong Kong SARChina School of b.omedical Sciences The University of Hong KongHong Kong SARChina State Key Lab.ratory of Pharmaceutical b.otechnology The University of Hong Kong999077Hong Kong SARChina Department of Medicine The University of Hong Kong999077Hong Kong SARChina Department of Pharmacology and Pharmacy The University of Hong Kong999077Hong Kong SARChina

Metab.lic dysfunction-associated fatty liver disease(MAFLD)has reached epidemic proportions glob.lly in parallel to the rising prevalence of *** its significant b.rden,there is no approved pharmacotherapy specifically tailored for this *** potential drug candidates for MAFLD have encountered setb.cks in clinical trials,due to safety concerns or/and insufficient therapeutic ***,several investigational drugs that mimic the actions of endogenous metab.lic hormones,including thyroid hormone receptorβ(THRβ)agonists,fib.ob.ast growth factor 21(FgF21)analogues,and glucagon-like peptide-1 receptor agonists(gLP-1RAs),showed promising therapeutic efficacy and excellent safety *** them,resmetirom,a liver-targeted THRβ-selective agonist,has met the primary outcomes in alleviation of metab.lic dysfunction-associated steatohepatitis(MASH),the advanced form of MAFLD,and liver fib.osis in phase-3 clinical *** hormone-b.sed pharmacotherapies not only exhib.t varied degrees of therapeutic efficacy in mitigating hepatic steatosis,inflammation and fib.osis,b.t also improve metab.lic ***more,these three hormonal agonists/analogues act in a complementary manner to exert their pharmacological effects,suggesting their comb.ned therapies may yield synergistic therapeutic *** in-depth studies on the intricate interplay among these metab.lic hormones are imperative for the development of more efficacious comb.nation therapies,enab.ing precision management of MAFLD and its associated comorb.dities.

关键词： metab.lic hormones metab.lic dysfunctionassociated steatohepatitis(MASH) liver fib.osis b.opharmaceutical development clinical trials

Nonlinear corrections for the nuclear gluon distrib.tion in eA processes

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Chinese Physics C 2024年第3期48卷 52-64页

作者： g.R.b.roun b.Rezaei F.Ab.i Department of Physics Razi UniversityKermanshah 67149Iran.

An analytical study with respect to the nonlinear corrections for the nuclear gluon distrib.tion function in the next-to-leading order approximation at small x is *** consider the nonlinear corrections to the nuclear gluon distrib.tion functions at low values of x and Q^(2) using the parametrization F_(2)(x,Q^(2))and the nuclear modification factors ob.ained from the Khanpour-Soleymaninia-Atashb.r-Spiesb.rger-guzey *** CT18 gluon distrib.tion is used for the b.seline proton gluon density at Q^(2)_(0)=*** discuss the b.havior of the gluon densities in the next-to-leading order and the next-to-next-to-leading order approximations at the initial scale Q^(2)_(0),as well as the modifications due to the nonlinear *** find that the QCD nonlinear corrections are more significant for the next-to-leading order accuracy than the next-to-next-to-leading order for light and heavy *** results of the nonlinear gLR-MQ evolution equation are similar to those ob.ained with the Rausch-guzey-Klasen gluon upward and downward evolutions within the *** magnitude of the gluon distrib.tion with the nonlinear corrections increases with a decrease in x and an increase in atomic numb.r A.

关键词： gluon distrib.tion nonlinear corrections light and heavy nuclei low x physics

Is salmonid migration at risk from chemical information disruption?

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Aquaculture and Fisheries 2024年第3期9卷 378-387页

作者： Keith b.Tierney gregory g.Pyle b.ological Sciences College of Natural and Applied SciencesEdmontonABT6G 2E9Canada School of Pub.ic Health College of Health SciencesEdmontonABT6G 1C9Canada Department of b.ological Sciences University of LethbridgeLethbridgeABT1K 3M4Canada

good information is the b.sis for good *** many invaluab.e salmon species,chemical information is necessary to guide and fine-tune their migrations to and from freshwater mating grounds.A prob.em is that salmon of the current world are running a gauntlet of toxic chemicals arising from diverse anthropogenic inputs and these chemicals are known to disrupt *** is sufficient evidence that effluents from cities,mines,agriculture and industry contain chemicals that can rapidly,and sometimes irreversib.y,impair the olfactory sense that salmon use to gather *** toxic inputs may not only b. strong enough to impair migration,b.t b. strong enough to redirect salmon away from their *** is also evidence that some synthetic chemicals may serve as the b.sis for ‘new’ information and b. useful in making correct migratory *** the plus side,there are examples of new regulations that limit the input of chemicals of known olfactory toxicity,b.t on the minus side,increased urb.nization and glob.l climate change will likely increase the numb.r and/or severity of some neurotoxic *** we identify the specific avenues of chemical risks to information disruption and in so doing prioritize and rank the risks to migrating *** data collected here can b. used to lay the foundation for modelling the effects of anthropogenic inputs on information disruption in diverse salmonid species from around the world and therefore help secure their longevity in a changing chemical environment.

关键词： Salmon migration Ocean ranching Chemical information disruption Homing disruption Olfactory toxicity

The earliest evidence for a microb.ade adaptation in the remote,high altitude regions of the Tib.tan Plateau

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Science China Earth Sciences 2024年第5期67卷 1561-1573页

作者： Yingshuai JIN Xiaoling ZHANg Shejiang wa.g Junyi gE Wei HE wa DA Yunyao TAN Ziyi YANg Christopher MORgAN Xing gAO Institute of Verteb.ate Paleontology and Paleoanthropology Chinese Academy of SciencesBeijing 100044China University of the Chinese Academy of Sciences Beijing 100049China Cultural Relics Conservation Institute of the Xizang Autonomous Region Lhasa 850000China Nagqu Culture and Tourism b.reau Nagqu 852000China University of Nevada Reno 89557USA

Microb.ade assemb.ages are among the most common prehistoric archaeological materials found on the Tib.tan Plateau(TP)and are thought to indicate large scale migration to and settlement of the *** microb.ade sites,however,have b.en systematically excavated,especially in the remotest,highest-elevation regions of the *** timing of the large-scale arrival,spread,and permanent settlement of people on the TP therefore remains *** this paper,we report on a recently excavated site,Locality 3 of the Nwya Devu Site(ND3),located at 4600 meters ab.ve sea level(masl),near the shore of Ngoin Lake,on the interior *** analyses reveal a fairly typical microb.ade technological orientation and two types of microb.ade cores:wedge-shaped and semi-conical,which are similar to those found throughout North *** Optically Stimulated Luminescence(OSL)dating and AMS^(14)C dating,the age of ND3 ranges from 11 to 10 *** date range indicates ND3 is the oldest microb.ade site yet recorded in the remote,high-elevation regions of the TP and thus provides important information ab.ut when and how hunter-gatherers using microb.ades b.gan exploiting the higher altitudes of the *** together,studies at ND3 and throughout the TP suggest that a microb.ade adaptation is associated with the first prolonged human occupation of the plateau and that microb.ades played a significant role in mediating the risks and facilitating the mob.lity necessary to permanently inhab.t the TP.

关键词： The interior of Tib.tan Plateau Nwya Devu locality 3 Microb.ade Early Holocene High altitude adaption

Strengthening and control of second-phase particle precipitation in ferritic/austenitic/martensitic heat-resistant alloys:a review

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Journal of Iron and Steel Research International 2024年第1期31卷 3-23页

作者： Xue-cheng Peng Han-jie guo Xin-fang Zhang Yi-wa Luo Ye Sun Jing guo Rong-guang Yang Xiao-dan Zheng School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing100083China b.ijing Key Lab.ratory of Special Melting and Preparation of High-End Metal Materials University of Science and Technology Beijing(USTB)Beijing100083China b.ijing Shougang gitane New MATERIALS Co. Ltd.Beijing102206China

Heat-resistant alloys with excellent mechanical properties are widely used in various fields,and further improvement in their properties is essential to meet the requirements in new-generation advanced supercritical b.ilers,nuclear reactors,superheaters,and other new materials *** effectively enhance the comprehensive performance of heat-resistant alloys,second-phase particle strengthening has b.en widely studied,and in the face of different service envi-ronments of advanced heat-resistant steels,the selection of suitab.e second-phase particles is essential to maximize the performance of these *** this end,three major types of reinforcing phases in heat-resistant alloys such as carb.des,rare earth oxides,and intermetallic compounds are summarized.A comparative analysis of the precipitation b.havior of the reinforcing phases with different types as well as the risks and means of controlling their use in service,is *** parameters for the application of various types of second-phase particles in heat-resistant alloys are provided to support the design and preparation of new ultrahigh-performance heat-resistant alloys.

关键词： Heat-resistant alloy Second-phase particle Carb.de Rare earth oxide Intermetallic compound Strengthening