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Experimental study on the feasibility of alternative materials for tilting pad thrust bearings operating in transition to mixed friction

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Friction 2024年第4期12卷 812-822页

作者： michałWAsIlCZUK michałWODTKE Faculty of Mechanical Engineering and ship Technology Gdańsk University of TechnologyGdańsk 80-233Poland

In hydrodynamic bearings traditional bearing alloys:Babbitts and bronzes are most frequently *** sliding layers are sometimes applied as a valuable *** diamond-like carbon(DlC)coatings,which are also considered for certain applications may show some advantages,as *** material selection is of secondary importance in a full film lubrication regime it becomes important in mixed friction conditions,which is crucial for bearings with frequent starts and *** research aimed at studying the performance of fluid film bearings in the specific operating regime,including the transition to mixed friction,is described in the *** tests were carried out on four tilting pad bearings of different material compositions:steel/bronze,DlC/steel,steel/polyether ether ketone(pEEK),and steel/*** tests comprised stopping under load and reproduction of the stribeck curve by decreasing rotational speed to very low values,and observing the changes of friction force during the transition to mixed friction *** of the transition conditions and other results showed clear differences between the tested bearings,illustrating the feasibility of less popular material compositions for bearings operating in specific *** specifically,the DlC/steel bearing was demonstrating superior performance,*** friction,transition to mixed friction occurring at higher load,and more stable performance at start-stop regime over the other tested bearings.

关键词： tilting pad thrust bearing experimental research start-stop regime polyether ether ketone(pEEK) diamond-like carbon(DlC)coating metallic bearing alloys

Getting the Most Out of Every Training Day: The Influence of Instructors on self-regulated learning During Firefighter leadership Courses

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International Journal of Disaster risk science 2024年第3期15卷 332-345页

作者： stefan r?seler micha Hilbert Guido Hertel Meinald T.Thielsch Department of psychology University of Münster

leadership courses in the fire services are highly challenging, and they can seriously exhaust trainees and hamper their selfregulated learning efforts(for example, setting goals, focusing attention, seeking feedback). We theorize that experiences of failure or overload can curtail trainees' available energy resources on subsequent training days, which, in turn, should affect trainees' learning efforts. Given instructors' central role in leadership courses, we hypothesize that supportive and humble instructor behaviors decrease experiences of failure and overload and, thus, increase self-regulated learning. Moreover, we argue that supportive instructor behavior may amplify the positive effects of high energy resources, while humble behavior may alleviate the negative impact of low resource levels. We tested preregistered hypotheses with 118 firefighters participating in two-week leadership courses at a German fire academy. The participants completed short web-based questionnaires before and after classes each day. Multilevel analyses confirmed that perceived daily supportive and humble instructor behavior predicted trainees' reports of daily self-regulated learning activity. Notably, this effect was independent from positive effects of trainees' reported energy resources in the morning. supportive and humble behavior did not moderate the eff ect of energy resources. Our findings suggest that instructors play a crucial role in facilitating effective learning under challenging training conditions. Furthermore, we offer implications for leaders in fire services, who often conduct trainings with their subordinates.

关键词： Diary study Fire services Instructor behavior leadership training resource investment

lE DEMI-sIClE, DE MOÏsE AU FIsCUs IUDAICUs. HIsTOIrE D’UNE TÉlÉOlOGIE

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Journal of Ancient Civilizations 2024年第1期39卷 73-98,124页

作者： michaël Girardin Universitédu littoral-Côte d’Opale

Many sources are brought together in scholarship in order to write the linear story of a specific tax,the half shekel tax paid each year by the Jews to the Temple of Jerusalem and,then,confiscated by the fiscus Iudaicus in roman *** do these sources refer to the same tax?In this paper,I defend the idea that the linearity of this story is a *** taxes were levied and justified by the memory of a Biblical tax,but they are all different in meaning,in administration and sometimes even in *** story is a political one:how to justify a tax in ancient Judaism?

关键词： didrachm fiscus Iudaicus half shekel Jerusalem Temple roman Judea taxation teleology

Effect of radiative loss mechanisms on FIr thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

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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 silva l.A.O.Nunes s.M.lima 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 Technology Center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of physics of são Carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(FIr)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the FIr parameters on the Nd^(3+)concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluorescence intensity ratio Optical thermometry Judd-Ofelt rare earths

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Chitin-glucan improves important pathophysiological features of irritable bowel syndrome

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World Journal of Gastroenterology 2024年第16期30卷 2258-2271页

作者： Caroline Valibouze Caroline Dubuquoy philippe Chavatte michaël Genin Veronique Maquet salvatore Modica pierre Desreumaux Christel rousseaux Department of Digestive surgery and Transplantation Lille UniversityLille 59037France Intestinal Biotech Development Facultéde MédicineLille 59045France U1286-INFINITE-Institute for Translational research in Inflammation Universitéde LilleLille 59000France Ulr 2694-METrICs Évaluation des Technologies de santéet des Pratiques MédicalesUniversity of LilleLille 59000France KitoZyme sA Institution SociétéAnonymeZone 2Parc des Hauts SartsRue de MilmortHerstal 4040Belgium Hepato-Gastroenterology Department Lille University HospitalLille 59037France

BACKGrOUND Irritable bowel syndrome(IBs)is one of the most frequent and debilitating conditions leading to gastroenterological ***,recommended treatments remain limited,yielding only limited therapeutic ***-glucan(CG)is a novel dietary prebiotic classically used in humans at a dosage of 1.5-3.0 g/d and is considered a safe food ingredient by the European Food safety *** provide an alternative approach to managing patients with IBs,we performed preclinical molecular,cellular,and animal studies to evaluate the role of chitin-glucan in the main pathophysiological mechanisms involved in *** To evaluate the roles of CG in visceral analgesia,intestinal inflammation,barrier function,and to develop computational molecular *** Visceral pain was recorded through colorectal distension(CrD)in a model of long-lasting colon hypersensitivity induced by an intra-rectal administration of TNBs[15 milligrams(mg)/kilogram(kg)]in 33 sprague-Dawley *** pressure was regularly assessed during the 9 wk-experiment(weeks 0,3,5,and 7)in animals receiving CG(n=14)at a human equivalent dose(HED)of 1.5 g/d or 3.0 g/d and compared to negative control(tap water,n=11)and positive control(phloroglucinol at 1.5 g/d HED,n=8)*** anti-inflammatory effect of CG was evaluated using clinical and histological scores in 30 C57bl6 male mice with colitis induced by dextran sodium sulfate(Dss)administered in their drinking water during 14 ***-29 cells under basal conditions and after stimulation with lipopolysaccharide(lps)were treated with CG to evaluate changes in pathways related to analgesia μ-opioid receptor(MOr),cannabinoid receptor 2(CB2),peroxisome proliferator-activated receptor alpha,inflammation[interleukin(Il)-10,Il-1b,and Il-8]and barrier function[mucin 2-5AC,claudin-2,zonula occludens(ZO)-1,ZO-2]using the real-time pCr *** modelling of CG,lps,lipoteichoic acid(lTA),and phospholipomannan(plM)was developed,and the abili

关键词： Chitin-glucan Irritable bowel syndrome Abdominal pain Inflammation Intestinal barrier Molecular modelling Microbial cell walls chelation

system integration analysis of a zeolite 13x thermal energy storage

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Energy and Built Environment 2024年第4期5卷 568-579页

作者： s.De Antonellis l.p.M.Colombo p.Castellazzi A.rossetti l.Marocco politecnico di Milano Department of Energyvia Lambruschini 4Milan 20156Italy ricerca sul sistema Energetico-rsE s.p.A. Tecnologie di Generazione e Materialivia R.Rubattino 54Milan 20134Italy

Nowadays a major energy transition aimed at cutting CO 2 emissions has begun,with the ambitious goal of drasti-cally reducing the dependence on fossil fuels and promoting the use of renewable energy *** this context,energy storage systems play a key role in ensuring a stable,secure and time-aligned energy *** sorption thermal energy storages(TEss)can contribute to such transition,since they are simple and cheap devices able to provide a hot airflow with a high energy density and to store energy for long *** this work,open sorption TEs systems operated with Zeolite13X are investigated with a focus on the integration in practical ***,the experimental analysis and modelling of the sole TEs system is ***,the integration of the TEs at system level is carried *** analysis evidences that a significant reduction of storage capac-ity occurs if air humidification is necessary before the adsorption process or afterwards to keep adequate indoor comfort conditions for the *** the exemplary case study considered,an energy density of 150 kWhm^(−3) can drop to 40 kWhm−3 in case of complete compensation of the adsorbed water through a *** paper provides useful guidelines for evaluating the performance of a TEs integrated system in terms of specific energy and *** also identifies applications involving high latent loads(e.g.,swimming pools,locker rooms)or for which low relative air humidity is required(*** of vehicles to prevent condensation on windows)as particularly beneficial for using a TEs system.

关键词： Energy storage Adsorption Zeolite system integration Numerical model

Convergent plate boundary environments for formation of≥3800 Ma mafic-ultramafic assemblages(Isua area,Greenland):Implications for early global geodynamics

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Geoscience Frontiers 2024年第3期15卷 119-136页

作者： Allen p.Nutman Clark r.l.Friend Vickie C.Bennett school of Earth Atmospheric and Life SciencesUniversity of WollongongWollongongNSW 2522Australia Glendale TiddingtonOxon OX92LQUK research school of Earth sciences Australian National UniversityCanberraACT 2601Australia

In the gneiss terrane on the south side of the Eoarchean Isua supracrustal belt,ultramafic rocks with relict abyssal peridotite mineralogy(Bennett et al.,2002;Friend et al.,2002;Nutman et al.,2007;rollinson,2007;van de löcht et al.,2020),layered gabbros with cumulate ultramafic rocks,basalts and associated siliceous sedimentary rocks were tectonically-imbricated,prior to and during intrusion of ca.3800 Ma *** with3800 Ma basalts in the Outer Arc Group of the nearby Isua supracrustal belt,the composition of all these mafic rocks(e.g.,Th-Hf-Nb systematics,high Th/Yb,Ba/Nb,Ba/Yb ratios and negative Nb and Ti anomalies)shows affinity with modern suprasubduction rocks whose genesis involved fluid fluxing of the upper ***,the majority of these samples have Ba/Nb and Ba/Yb values less than in modern island arc magmas,but similar to many backarc basin magmas(e.g.,pearce and stern,2006).It is unknown whether these ca.3800 Ma mafic rocks are,(i)arc rocks where the Ba/Nb and Ba/Yb signatures reflect lower surficial Ba in Eoarchean oceanic settings,or(ii)in direct comparison with phanerozoic suites,these signatures reflect a back-arc setting with interplay between fluid fluxing and decompressional *** tectonic intercalation of upper mantle with lower and upper crustal rocks,combined with the fluid-fluxing influences seen in chemistry of all the mafic rocks is best accommodated in a compressional Eoarchean convergent plate boundary setting within a mobile-lid *** stagnant lid scenarios of crust formation,if operative,must have co-existed or alternated with mobile-lid regimes by 3800 Ma.

关键词： Eoarchean Fluid-fluxing plate tectonics suprasubduction Crustal evolution

Exact solutions for magnetohydrodynamic nanofluids flow and heat transfer over a permeable axisymmetric radially stretching/shrinking sheet

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Chinese physics B 2024年第2期33卷 108-114页

作者： U.s.Mahabaleshwar G.p.Vanitha l.M.pérez Emad H.Aly I.pop Department of studies in Mathematics Davangere UniversityShivagangothriDavangereIndia Departamento de F´ısica FACIUniversidad de Tarapac´aCasilla 7DAricaChile Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt Department of Mathematics Babes-Bolyai University400084 Cluj-NapocaRomania

We report on the magnetohydrodynamic impact on the axisymmetric flow of Al_(2)O_(3)/Cu nanoparticles suspended in H_(2)O past a stretched/shrinked *** the use of partial differential equations and the corresponding thermophysical characteristics of nanoparticles,the physical flow process is *** resultant nonlinear system of partial differential equations is converted into a system of ordinary differential equations using the suitable similarity *** transformed differential equations are solved *** of the magnetic parameter,solid volume fraction and stretching/shrinking parameter on momentum and temperature distribution have been analyzed and interpreted *** skin friction and Nusselt number were also *** addition,existence of dual solution was deduced for the shrinking sheet and unique solution for the stretching ***,Al_(2)O_(3)/H_(2)O nanofluid flow has better thermal conductivity on comparing with Cu/H_(2)O ***,it was found that the first solutions of the stream are stable and physically realizable,whereas those of the second ones are unstable.

关键词： magnetohydrodynamic nanofluid stretching/shrinking sheet axisymmetric flow analytical solution suction/injection

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On the functions of astrocyte-mediated neuronal slow inward currents

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Neural regeneration research 2024年第12期19卷 2602-2612页

作者： Balázs pál Department of physiology Faculty of MedicineUniversity of DebrecenDebrecenHungary

slow inward currents are known as neuronal excitatory currents mediated by glutamate release and activation of neuronal extra synaptic N-met hyl-D-aspartate receptors with the contribution of *** events are significantly slower than the excitatory postsynaptic *** of slow inward currents are determined by seve ral factors including the mechanisms of astrocytic activation and glutamate release,as well as the diffusion pathways from the release site towards the extra synaptic recepto *** are stimulated by neuronal network activity,which in turn excite neurons,forming an astrocyte-neuron feedback *** as a consequence of brain edema,astrocytic swelling can also induce slow inward currents under pathological *** is a growing body of evidence on the roles of slow inward currents on a single neuron or local network *** events often occur in synchro ny on neurons located in the same astrocytic *** synchronization of neuronal excitability,slow inward currents also set synaptic strength via eliciting timing-dependent synaptic *** addition,slow inward currents are also subject to non-synaptic plasticity triggered by long-la sting stimulation of the excitatory *** note,there might be important regionspecific differences in the roles and actions triggering slow inward *** greater networks,the pathophysiological roles of slow inward currents can be better understood than physiological *** inward currents are identified in the pathophysiological background of autism,as slow inward currents drive early hypersynchrony of the neural *** inward currents are significant contributors to paroxysmal depolarizational shifts/interictal *** events are related to epilepsy,but also found in Alzheimer's disease,parkinson's disease,and stroke,leading to the decline of cognitive *** with features overlapping with slow inward currents(excitatory,N-methyl-Dasp

关键词： astrocyte cortical spreading depolarization gliotransmission glutamate neural synchronization NMDA receptor paroxysmal depolarizational shift slow inward current

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