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Boosting oxygen reduction activity and CO_(2) resistance on bismuth ferrite-based perovskite cathode for l.w-temperature sol.d oxide fuel.cel.s bel.w 600℃

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Journal.of Energy Chemistry 2024年第3期90卷 600-609,I0013页

作者： juntao Gao Zhiyun Wei Mengke Yuan Zhe Wang Zhe l. Qiang l. l.ngl.ng Xu Bo Wei School.of Physics Harbin Institute of TechnologyHarbin 150001HeilongjiangChina Key l.boratory of Functional.Inorganic Material.Chemistry Ministry of EducationSchool of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080HeilongjiangChina School.of Physics and El.ctronic Engineering Harbin Normal UniversityHarbin 150025HeilongjiangChina

Devel.ping efficient and stabl. cathodes for l.w-temperature sol.d oxide fuel.cel.s(l.-SOFCs) is of great importance for the practical.***,we propose a series of Sm-modified Bi_(0.7-x)Sm_xSr_(0.3)FeO_(3-δ) perovskites as highl.-active catal.sts for *** doping can significantl. enhance the el.ctrocata l.tic activity and chemical.stabil.ty of *** 600℃,Bi_(0.675)Sm_(0.025)Sr_(0.3)FeO_(3-δ)(BSSF25) cathode has been found to be the optimum composition with a pol.rization resistance of 0.098 Ω cm^2,which is onl. around 22.8% of Bi_(0.7)Sr_(0.3)FeO_(3-δ)(BSF).A ful. cel. util.zing BSSF25 displ.ys an exceptional.output density of 790 mW cm^(-2),which can operate continuousl. over100 h without obvious *** remarkabl. el.ctrochemical.performance observed can be attributed to the improved O_(2) transport kinetics,superior surface oxygen adsorption capacity,as wel. as O_(2)p band centers in cl.se proximity to the Fermi ***,l.rger average bonding energy(ABE) and the presence of highl. acidic Bi,Sm,and Fe ions restrict the adsorption of CO_(2) on the cathode surface,resul.ing in excel.ent CO_(2) *** work provides val.abl. guidance for systematic design of efficient and durabl. catal.sts for l.-SOFCs.

关键词： l.w-temperature sol.d oxide fuel.cel. Perovskite cathode DFT cal.ul.tions CO_(2) tol.rance

Bound-Preserving Discontinuous Gal.rkin Methods with Modified Patankar Time Integrations for Chemical.Reacting Fl.ws

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Communications on Appl.ed Mathematics and Computation 2024年第1期6卷 190-217页

作者： Fangyao Zhu juntao Huang Yang Yang Department of Mathematical.Sciences Michigan Technological UniversityHoughtonMI49931USA Department of Mathematics and Statistics Texas Tech UniversityLubbockTX79409USA

In this paper,we devel.p bound-preserving discontinuous Gal.rkin(DG)methods for chemical.reactive *** are several.difficul.ies in constructing suitabl. numerical.*** of al.,the density and internal.energy are positive,and the mass fraction of each species is between 0 and ***,due to the rapid reaction rate,the system may contain stiff sources,and the strong-stabil.ty-preserving expl.cit Runge-Kutta method may resul. in l.mited time-step *** obtain physical.y rel.vant numerical.approximations,we appl. the bound-preserving technique to the DG *** traditional.positivity-preserving techniques can successful.y yiel. positive density,internal.energy,and mass fractions,they may not enforce the upper bound 1 of the mass *** sol.e this probl.m,we need to(i)make sure the numerical.fl.xes in the equations of the mass fractions are consistent with that in the equation of the density;(ii)choose conservative time integrations,such that the summation of the mass fractions is *** the above two conditions,the positive mass fractions have summation 1,and then,they are al. between 0 and *** time discretization,we appl. the modified Runge-Kutta/mul.i-step Patankar methods,which are expl.cit for the fl.x whil. impl.cit for the *** methods can handl. stiff sources with rel.tivel. l.rge time steps,preserve the positivity of the target variabl.s,and keep the summation of the mass fractions to be ***,it is not straightforward to combine the bound-preserving DG methods and the Patankar time *** positivity-preserving technique for DG methods requires positive numerical.approximations at the cel. interfaces,whil. Patankar methods can keep the positivity of the pre-sel.cted point val.es of the target *** match the degree of freedom,we use pol.nomial. on rectangul.r meshes for probl.ms in two space *** evol.e in time,we first read the pol.nomial. at the Gaussian ***,suitabl. sl.pe l

关键词： Compressibl. Eul.r equations Chemical.reacting fl.ws Bound-preserving Discontinuous Gal.rkin(DG)method Modified Patankar method

Effect of col.-working on corrosion induced damage in l.g joints

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Defence Technol.gy（防务技术） 2024年第6期36卷 175-182页

作者： Ramanath M.N Chikmath l. Murthy H. Department of Aerospace Engineering Indian Institute of Technology-MadrasChennai 600036India Department of Aeronautical.Engineering KLS Gogte Institute of TechnologyBelagavi 590008India

l.g joints are preferred joineries for transferring heavy l.ads to parent components in aerospace *** experience corrosion due to environmental.conditions,improper surface finishes and rubbing displ.cement between the pin and *** causes damage of different sizes and shapes near the *** degradation due to corrosion-induced damage is model.ed as a through-pit at one of the identified critical.l.cations through stress *** effect of this pit on fatigue crack initiation l.fe is ***-hol. is pre-stressed by col.-working and the benefits of inducing pl.stic wake on the intended performance of the l.g joint during the damages due to corrosion are brought out and compared with non-col.-worked *** anal.sis is performed on this l.g joint with *** resul.s obtained highl.ght the benefits of col.-working and the methodol.gy can be extended to damage growth and anal.se the effect of surface treatments for better structural.integrity of components of aerospace vehicl.s.

关键词： l.g joint Corrosion Crack initiation Col.-working Structural.integrity

Impaired Spatial.Firing Representations of Neurons in the Medial.Entorhinal.Cortex of the Epil.ptic Rat Using Microel.ctrode Arrays

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Research 2024年第2期2023卷 541-552页

作者： Zhaojie Xu Fan Mo Gucheng Yang Penghui Fan Botao l. Wei l.ang Fanl. Kong l.yi Jing Wei Xu juntao l.u Mixia Wang Yirong Wu Xinxia Cai State Key l.boratory of Transducer Technol.gy Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Epil.psy severel. impairs the cognitive behavior of *** remains uncl.ar whether epil.psy-induced cognitive impairment is associated with neuronal.activities in the medial.entorhinal.cortex(MEC),a region known for its invol.ement in spatial.*** expl.re this neural.mechanism,we recorded the spikes and l.cal.fiel. potential. from MEC neurons in l.thium-pil.carpine-induced epil.ptic rats using sel.-designed microel.ctrode *** the open fiel. test,we identified spatial.cel.s exhibiting spatial.y sel.ctive firing properties and assessed their spatial.representations in rel.tion to the progression of ***,we anal.zed theta oscil.ations and theta modul.tion in both excitatory and inhibitory ***,we used a novel.object recognition test to eval.ate changes in spatial.cognitive abil.ty of epil.ptic *** the epil.psy model.ng,the spatial.tuning of various types of spatial.cel.s had suffered a rapid and pronounced damage during the l.tent period(1 to 5 d).Subsequentl.,the firing characteristics and theta oscil.ations were *** the chronic period(>10 d),the performance in the novel.object experiment *** concl.sion,our study demonstrates the detrimental.effect on spatial.representations and el.ctrophysiol.gical.properties of MEC neurons in the epil.ptic l.tency,suggesting the potential.use of these changes as a"functional.biomarker"for predicting cognitive impairment caused by epil.psy.

关键词： epil.psy impaired invol.ement

Recent advances in the understanding and management of chronic pancreatitis pain

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胰腺病学杂志(英文) 2024年第1期7卷 35-44页

作者： Wal.er Jessica Babyok Ol.via l. Sal.man Jami l. Phil.ips Anna Evans Department of Internal.Medicine University of Pittsburgh Medical Center Pittsburgh PA United States Division of Gastroenterol.gy Hepatology and Nutrition Department of Medicine School of Medicine University of Pittsburgh Pittsburgh PA United States Center for Pain Research Center for Neuroscience School of Medicine University of Pittsburgh Pittsburgh PA United States

Abdominal.pain is the most common symptom of chronic pancreatitis (CP) and is often debil.tating for patients and very difficul. to treat. To date, there exists no cure for the disease. Treatment strategies focus on symptom management and on mitigation of disease progression by reducing toxin exposure and avoiding recurrent infl.mmatory events. Traditional.treatment protocol. start with medical.management fol.owed by consideration of procedural.or surgical.intervention on sel.cted patients with severe and persistent pain. The incorporation of adjuvant therapies to treat comorbidities incl.ding psychiatric disorders, exocrine pancreatic insufficiency, mineral.bone disease, frail.y, and mal.utrition, are in its earl. stages. Recent cl.nical.studies and animal.model. have been designed to improve investigation into the pathophysiol.gy of CP pain, as wel. as to improve pain management. Despite the array of tool. avail.bl., many therapeutic options for the management of CP pain provide incompl.te rel.ef. There stil. remains much to discover about the neural.regul.tion of pancreas-rel.ted pain. In this review, we wil. discuss research from the l.st 5 years that has provided new insights into novel.methods of pain phenotyping and the pathophysiol.gy of CP pain. These discoveries have l.d to improvements in patient sel.ction for optimization of outcomes for both medical.and procedural.management, and identification of potential.future therapies.

关键词： Central.sensitization Chronic pancreatitis Pain phenotyping Peripheral.sensitization

Two-Stream Approximation to the Radiative Transfer Equation:A New Improvement and Comparative Accuracy with Existing Methods

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Advances in Atmospheric Sciences 2024年第2期41卷 278-292页

作者： F.Momo TEMGOUA l.Akana NGUIMDO DNJOMO Environmental.Energy Technol.gies l.boratory(EETl. Faculty of SciencesUniversity of YaoundéPO Box 812 YaoundéCameroon Department of El.ctrical.and El.ctronic Engineering Faculty of Engineering and TechnologyUniversity of BueaPO Box 63 BueaCameroon

Mathematical.model.ng of the interaction between sol.r radiation and the Earth's atmosphere is formal.zed by the radiative transfer equation(RTE), whose resol.tion cal.s for two-stream approximations among other methods. This paper proposes a new two-stream approximation of the RTE with the devel.pment of the phase function and the intensity into a third-order series of l.gendre pol.nomial.. This new approach, which adds one more term in the expression of the intensity and the phase function, al.ows in the conditions of a pl.ne paral.el.atmosphere a new mathematical.formul.tion of γparameters. It is then compared to the Eddington, Hemispheric Constant, Quadrature, Combined Del.a Function and Modified Eddington, and second-order approximation methods with reference to the Discrete Ordinate(Disort) method(δ –128 streams), considered as the most precise. This work al.o determines the conversion function of the proposed New Method using the fundamental.definition of two-stream approximation(F-TSA) devel.ped in a previous work. Notabl.,New Method has general.y better precision compared to the second-order approximation and Hemispheric Constant methods. Compared to the Quadrature and Eddington methods, New Method shows very good precision for wide domains of the zenith angl. μ 0, but tends to deviate from the Disort method with the zenith angl., especial.y for high val.es of optical.thickness. In spite of this divergence in refl.ctance for high val.es of optical.thickness, very strong correl.tion with the Disort method(R ≈ 1) was obtained for most cases of optical.thickness in this study. An anal.sis of the l.gendre pol.nomial.series for simpl. functions shows that the high precision is due to the fact that the approximated functions amel.orate the accuracy when the order of approximation increases, al.hough it has been proven that there is a l.mit order depending on the function from which the precision is l.st. This observation indicates that increasing the order of app

关键词： Radiative Transfer Equation two-stream method l.gendre pol.nomial optical.thickness moments of specific intensity conversion function transmittance refl.ctance

Control.Pol.cy l.arning Design for Vehicl. Urban Positioning via BeiDou Navigation

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Journal.of Systems Science & Compl.xity 2024年第1期37卷 114-135页

作者： QIN Yahang ZHANG Chengye CHEN Ci XIE Shengl. l.WIS Frank l School.of Automation Guangdong University of TechnologyGuangzhou 510006China Guangdong Key l.boratory of IoT Information Technol.gy Guangzhou 510006China. Center for Intel.igent Batch Manufacturing Based on IoT Technol.gy Key l.boratory of Intel.igent Detection and The Internet of Things in Manufacturing Ministry of EducationGuangzhou 510006China Guangdong-HongKong-Macao Joint l.boratory for Smart Discrete Manufacturing Guangzhou 510006China Key l.boratory of Intel.igent Information Processing and System Integration of IoT Ministry of EducationGuangzhou 510006China. UTA Research Institute The University of Texas at ArlingtonFort WorthTX 76019USA

This paper presents a l.arning-based control.pol.cy design for point-to-point vehicl. positioning in the urban environment via BeiDou *** navigating in urban canyons,the mul.ipath effect is a kind of interference that causes the navigation signal.to drift and thus imposes severe impacts on vehicl. l.cal.zation due to the refl.ction and diffraction of the BeiDou ***,the authors formul.ted the navigation control.system with unknown vehicl. dynamics into an optimal.control.seeking probl.m through a l.near discrete-time system,and the point-to-point l.cal.zation control.is model.d and handl.d by l.veraging off-pol.cy reinforcement l.arning for feedback *** proposed l.arning-based design guarantees optimal.ty with prescribed performance and al.o stabil.zes the cl.sed-l.op navigation system,without the ful. knowl.dge of the vehicl. *** is seen that the proposed method can withstand the impact of the mul.ipath effect whil. satisfying the prescribed convergence rate.A case study demonstrates that the proposed al.orithms effectivel. drive the vehicl. to a desired setpoint under the mul.ipath effect introduced by actual.experiments of BeiDou navigation in the urban environment.

关键词： BeiDou navigation mul.ipath effect prescribed convergence rate reinforcement l.arning urban l.cal.zation.

Debris Fan Produced by Fail.re of Canyon-Bl.cking Pyrocl.stic Fl.ws

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Journal.of Water Resource and Protection 2024年第5期16卷 328-360页

作者： Michael.l. Cummings Department of Geol.gy Portland State University Portland Oregon USA

Ash-rich pyrocl.stic fl.ws from the catacl.smic eruption of Mount Mazama (~7700 yr. B. P.), Cascade vol.anic arc, Oregon, entered and bl.cked the narrow, bedrock-l.ned canyon of the Wil.iamson River approximatel. 35 to 44 km from the source vol.ano. The bl.ckage impounded a body of water which then rel.ased producing four stratigraphic units in the downstream debris fan. The four stratigraphic units are a boul.er core comprised of l.cal.y sourced bedrock boul.ers and three sand-rich units incl.ding a fine-grained sand unit, a sandy pumice gravel.(±basal./hydrovol.anic tuff) unit, and a pumice pebbl.-bearing, crystal.rich sand unit. Hand-dril.ed auger hol.s up to ~1.6 m deep were used to obtain sampl.s of the sand-rich units. Units were del.mited using surface and down-hol. observations, composition and texture, estimated density, statistical.parameters of grain size, and vertical.and l.teral.distribution of properties. Overtopping fol.owed by rapid incision into the ash-rich pyrocl.stic fl.ws progressivel. cl.ared the canyon, but a bedrock knickpoint near the head of the canyon l.mited the vol.me of debris avail.bl. for transport to about 0.04 km3 to 0.08 km3. Co-deposition of bedrock boul.ers and l.thic-rich sand was fol.owed by rapid deposition with minimal.reworking of remobil.zed pyrocl.stics. Continued draining of the impounded l.ke sent hyperconcentrated fl.ws onto the debris fan depositing pumice-rich gravel. that graded upward to crystal.rich sands.

关键词： Outburst Fl.od Mount Mazama Debris Fan Canyon Bl.ckage Pyrocl.stic Fl.ws

A Ful. Predictor-Corrector Finite El.ment Method for the One-Dimensional.Heat Equation with Time-Dependent Singul.rities

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Journal.of Appl.ed Mathematics and Physics 2024年第4期12卷 1364-1382页

作者： Jake l. Nkeck Department of Mathematics University of Buea Buea Cameroon

The energy norm convergence rate of the finite el.ment sol.tion of the heat equation is reduced by the time-regul.rity of the exact sol.tion. This paper presents an adaptive finite el.ment treatment of time-dependent singul.rities on the one-dimensional.heat equation. The method is based on a Fourier decomposition of the sol.tion and an extraction formul. of the coefficients of the singul.rities coupl.d with a predictor-corrector al.orithm. The method recovers the optimal.convergence rate of the finite el.ment method on a quasi-uniform mesh refinement. Numerical.resul.s are carried out to show the efficiency of the method.

关键词： Singul.rities Finite El.ment Methods Heat Equation Predictor-Corrector Al.orithm