检索结果-南通市图书馆

Wear protection assessment of ultralow viscosity lubricants in high-power-density engines:A novel wear prediction algorithm

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Friction 2024年第8期12卷 1785-1800页

作者： Javier BlANCO-RODRÍGUEZ Jacobo PORTEIRO joséA.lÓpez-CAMPOS MartíCORTADA-GARCÍA Silvia FERNÁNDEZ-CASTEJÓN CINTECX Universidade de VigoLagoas-Marcosende s/nVigo 36310Spain Repsol SA MadridSpain

Durability and reliability have been studied for decades through intensive trial-error ***,there are numerous fields of application where the costs associated with this approach are not *** lubricated machines with severe dynamic loads,such as high-power-density engines,simulation tools offer clear advantages over intensive *** and multiple scenarios can be cost-effectively simulated to assess different lubricants and engine *** work presented here details the study of wear based on a validated elastohydrodynamic(EHD)simulation model of the connecting rod journal *** model accounts for elastic deformation through a connecting rod finite element model(FEM).In addition,multiple lubricant rheological and tribological dependences,determined by specific experimental tests,are applied in the model through their interaction with the simulation ***,a novel wear algorithm is proposed to predict wear depth over time evolution along a proposed wear cycle based on the typical working ranges of high-performance engines.A final assessment is presented to compare 4 different ultralow-viscosity lubricants in their protective performance under severe *** results show the evolution of the wear load and wear depth over the wear *** evaluation is key to describing a lubricant selection procedure for high-power-density engines.

关键词： wear modelling finite element modelling mixed lubrication elastohydrodynamic(EHD) internal combustion engines bearings

Enhancement of the CO_(2)adsorption and hydrogenation to CH_(4)capacity of Ru–Na–Ca/γ–Al_(2)O_(3)dual function material by controlling the Ru calcination atmosphere

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第6期140卷 292-305页

作者： Alejandro Bermejo-lópez Beñat Pereda-Ayo Jon A.Onrubia-Calvo joséA.González-Marcos Juan R.González-Velasco Department of Chemical Engineering Faculty of Science and TechnologyUniversidad del País Vasco UPV/EHUBarrio Sarrienas/n48940 LeioaBizkaiaSpain

Integrated CO_(2)capture and utilization(ICCU)technology requires dual functional materials(DFMs)to carry out the process in a single reaction *** influence of the calcination atmosphere on efficiency of 4%Ru-8%Na_(2)CO_(3)-8%CaO/γ-Al_(2)O_(3)DFM is *** adsorbent precursors are first co-impregnated onto alumina and calcined in ***,Ru precursor is impregnated and four aliquotes are subjected to different calcination protocols:static air in muffle or under different mixtures(10%H_(2)/N_(2),50%H_(2)/N_(2)and N_(2))*** are characterized by XRD,N_(2)adsorption-desorption,H_(2)chemisorption,TEM,XPS,H_(2)-TPD,H_(2)-TPR,CO_(2)-TPD and *** catalytic behavior is evaluated,in cycles of CO_(2)adsorption and hydrogenation to CH_(4),and temporal evolution of reactants and products concentrations is *** calcination atmosphere influences the physicochemical properties and,ultimately,activity of *** data and catalytic performance discover the acccomodation of Ru nanoparticles disposition and basic sites is mostly influencing the catalytic *** calcined under N_(2)flow(RuNaCa-N_(2))shows the highest CH_(4)production(449μmol/g at 370℃),because a well-controlled decomposition of precursors which favors the better accomodation of adsorbent and Ru phases,maximizing the specific surface area,the Ru-basic sites interface and the participation of different basic sites in the CO_(2)methanation ***,the calcination in a N_(2)flow is revealed as the optimal calcination protocol to achieve highly efficient DFM for integrated CO_(2)adsorption and hydrogenation applications.

关键词： CO_(2)methanation Integrated CO_(2)capture and utilization(ICCU) Dual functional material(DFM) Ru calcination atmosphere

Experimental implementation of phase triplicator gratings in a spatial.light modulator

在线全文

学校读者我要写书评

暂无评论

Chinese Optics letters 2024年第2期22卷 64-69页

作者：高尚 María del Mar Sánchez-lópez Ignacio Moreno Instituto de Bioingeniería Universidad Miguel HernándezElche 03202Spain Departamento de Física Aplicada Universidad Miguel HernándezElche 03202Spain Departamento de Ciencia de Materiales Óptica y Tec.Electr´onicaUniversidad Miguel HernándezElche 03202Spain

In this work,we compare different methods for implementing a triplicator,a phase grating that generates three equiintense diffraction *** design with optimal efficiency features a continuous phase profile,which cannot be easily reproduced,and is typically affected by *** compare its performance with binary and sinusoidal phase *** also analyze the effect of quantizing the phase ***,a random approach is adopted to eliminate the additional harmonic *** all cases,a liquid-crystal-on-silicon spatial.light modulator is employed to experimentally verify and compare the different approaches.

关键词： diffraction gratings phase modulation triplicator spatial.light modulators

Metal-modulated epitaxy of Mg-doped Al_(0.80)In_(0.20)N-based layer for application as the electron blocking layer in deep ultraviolet light-emitting diodes

在线全文

学校读者我要写书评

暂无评论

Journal of Semiconductors 2024年第5期45卷 80-89页

作者： Horacio Irán Solís-Cisneros Carlos Alberto Hernández-Gutiérrez Enrique Campos-González Máximo lópez-lópez Optomechatronics Group Tecnológico Nacional de México Campus Tuxtla Gutiérrezcarretera Panamericana 1080C.P.29050Tuxtla GutiérrezChiapasMéxico Departamento de Física Instituto Nacional de Investigaciones NuclearesCarretera México-Toluca s/nC.P.52750La Marquesa OcoyoacacMéxico Departamento de Física Centro de Investigación y estudios Avanzados del Instituto Politécnico NacionalAv.Instituto Politécnico Nacional 2508San Pedro ZacatencoGustavo A.Madero07360 Ciudad de MéxicoCDMXMéxico

This work reports the growth and characterization of p-AlInN layers doped with Mg by plasma-assisted molecular beam epitaxy(PAMBE).AlInN was grown with an Al molar fraction of 0.80 by metal-modulated epitaxy(MME)with a thickness of 180 nm on Si(111)substrates using AlN as buffer *** substrate temperatures were used to enhance the incorporation of indium atoms into the alloy without clustering,as confirmed by X-ray diffraction(XRD).Cathodoluminescence measurements revealed ultraviolet(UV)range ***,Hall effect measurements indicated a maximum hole mobility of 146 cm^(2)/(V∙s),corresponding to a free hole concentration of 1.23×10^(19)cm^(−3).The samples were analyzed by X-ray photoelectron spectroscopy(XPS)estimating the alloy composition and extracting the Fermi level by valence band ***-doped AlInN layers were studied for use as the electron-blocking layer(EBl)in lED *** varied the Al composition in the EBl from 0.84 to 0.96 molar fraction to assess its theoretical effects on electroluminescence,carrier concentration,and electric field,using SIlVACO *** results from this study highlight the importance and capability of producing high-quality Mg-doped p-AlInN layers through *** simulations suggest that an Al content of 0.86 is optimal for achieving desired outcomes in electroluminescence,carrier concentration,and electric field.

关键词： metal-modulated epitaxy AlInN DUV-lED EBl simulation

Oligodendroctyes:the forgotten players of diabetes pathophysiology

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2024年第11期19卷 2349-2350页

作者： Juan Antonio lópez-Villodres Beatriz García-Díaz Departamento Fisiología Humana Histología HumanaAnatomía Patológica y Educación Física y DeportivaFacultad de MedicinaUniversidad de MálagaMálagaSpain UGC Neurociencia.Instituto de Investigación Biomédica de Málaga y Plataforma en Nanomedicina(IBIMA Plataforma Bionand) MálagaSpain

Oligodendrocytes(Ols),glial cells that provide myelin sheaths to axons in the central nervous system(CNS),have a dual ***,this myelin fatty cover around the axons protects the nerves and is crucial for the saltatory propagation of action *** and not less important,Ols provide trophic support to neurons and ***,Ol metabolism is important for Ol well-being and the proper accomplishment of their functions,and Ol metabolism energetics directly affect the energy metabolism of neighboring neurons.

关键词： metabolism nerves myelin

Electrifying Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ) for focalized heating in oxygen transport membranes

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第4期91卷 99-110页

作者： Marwan laqdiem Julio García-Fayos laura Almar Alfonso J.Carrillo Álvaro Represa joséM.lópez Nieto Sonia Escolástico David Catalán-Martinez jose M.Serra Instituto de Tecnología Química(Universitat Politècnica de València–Consejo Superior de Investigaciones Científicas) Av.Los Naranjos s/nE-46022 ValenciaSpain

Industry decarbonization requires the development of highly efficient and flexible technologies relying on renewable energy resources,especially biomass and solar/wind *** the case of pure oxygen production,oxygen transport membranes(OTMs)appear as an alternative technology for the cryogenic distillation of air,the industrially-established process of producing ***,OTMs could provide oxygen from different sources(air,water,CO_(2),etc.),and they are more flexible in adapting to current processes,producing oxygen at 700^(-1)000℃.Furthermore,OTMs can be integrated into catalytic membrane reactors,providing new pathways for different *** first part of this study was focused on electrification on a traditional OTM material(Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ)),imposing different electric currents/voltages along a capillary *** to the emerging Joule effect,the membrane-surface temperature and the associated O_(2) permeation flux could be ***,the OTM is electrically and locally heated and reaches 900℃on the surface,whereas the surrounding of the membrane was maintained at 650℃.The O_(2)permeation flux reached for the electrified membranes was~3.7 Nml min^(-1)cm^(-2),corresponding to the flux obtained with an OTM non-electrified at 900℃.The influence of depositing a porous Ce_(0.8)Tb_(0.2)O_(2-δ) catalytic/protective layer on the outer membrane surface revealed that lower surface temperatures(830℃)were detected at the same imposed electric ***,the electrification concept was demonstrated in a catalytic membrane reactor(CMR)where the oxidative dehydrogenation of ethane(ODHE)was carried *** reaction is very sensitive to temperature,and here,we demonstrate an improvement of the ethylene yield by reaching moderate temperatures in the reaction chamber while the O_(2) injection into the reaction can be easily fine-tuned.

关键词： Oxygen permeation Oxidative dehydrogenation of ethane Oxygen transport membranes Joule effect Mixed ionic-electronic conductors Catalytic membrane reactors

Experimental and numerical investigation to elucidate the fluid flow through packed beds with structured particle packings

在线全文

学校读者我要写书评

暂无评论

Particuology 2024年第6期89卷 218-237页

作者： Shirin Patil Christian Gorges Joel.lòpez Bonilla Moritz Stelter Frank Beyrau Berend van Wachem laboratory of Technical Thermodynamics Otto-von-Guericke-Universität MagdeburgUniversitätsplatz 239106 MagdeburgGermany Chair of Mechanical Process Engineering Otto-von-Guericke-Universität MagdeburgUniversitätsplatz 239106 MagdeburgGermany

The present paper presents an experimental and numerical investigation of the dispersion of the gaseous jet flow and co-flow for the simple unit cell(SUC)and body-centred cubic(BCC)configuration of particles in packed *** experimental setup is built in such a way that suitable and simplified boundary conditions are imposed for the corresponding numerical framework,so the simulations can be done under very similar conditions as the ***,a porous plate is used for the co-flow to achieve the uniform velocity and the fully developed flow is ensured for the jet *** SUC and BCC particle beds consist of 3D-printed spheres,and the non-isotropy near the walls is mostly eliminated by placing half-spheres at the channel *** flow velocities are analysed directly at the exit of the particle bed for both beds over 36 pores for the SUC configuration and 60 pores for the BCC configuration,for particle Reynolds numbers of 200,300,and *** particle image velocimetry is experimentally arranged in such a way that the velocities over the entire region at the exit of the packed bed are obtained *** numerical method consists of a state-of-the-art immersed boundary method with adaptive mesh *** paper presents the pore jet structure and velocity field exiting from each pore for the SUC and BCC packed particle *** numerical and experimental studies show a good agreement for the SUC configuration for all flow *** the BCC configuration,some differences can be observed in the pore jet flow structure between the simulations and the experiments,but the general flow velocity distribution shows a good overall *** axial velocity is generally higher for the pores located near the centre of the packed bed than for the pores near the *** addition,the axial velocities are observed to increase near the peripheral pores of the packed *** behaviour is predominant for the BCC configuration as compared to t

关键词： Uniform particle packing Packed bed reactor Stereo particle image velocimetry Immersed boundary method

Digital Social Connectedness as a lifeline for Older People: Use and Non-use of VinclesBCN During the Pandemic

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Disaster Risk Science 2024年第2期15卷 251-264页

作者： Israel Rodríguez‑Giralt Daniel.lópez‑Gómez Roser Beneito‑Montagut CareNet IN3Universitat Oberta de Catalunya08018 BarcelonaSpain School of Social Sciences Cardif UniversityCardif CF103NSWalesUK

This article presents the results of a study that evaluated VinclesBCN during COVID-19. This digital-based public social service aims to prevent loneliness and isolation in +65-year-old adults living in Barcelona. Through service user(N = 12) and professional(N = 6) interviews and a questionnaire with service users(N = 255), we demonstrate the pivotal role of digital connectedness in transforming VinclesBCN into a lifeline during the pandemic. The analysis revealed the importance of sociability, social support, and, especially, entertainment in coping with pandemic fatigue and facilitating social connectivity and support among users. Users engaged in activities such as sharing images, songs, memes, and daily greetings to provide proximity, sociability, and care among users, whether they belonged to preexisting groups or were newly introduced to the platform. It also facilitated the identification of individuals who needed companionship, comfort, or more specialized support. The findings emphasize the significance of entertainment as a resilience-building strategy during times of uncertainty. Despite the positive impact, not all users equally used the platform. Non-use was strongly associated with being a woman, having a low educational.level, having preexisting social relationships, less time of enrolment in the platform, as well as a high perception of loneliness, poor self-reported health, and low mood. The article underscores the need for further research into older adults' digital engagement during crises, its role in building resilience, and advocating for inclusive digital interventions that take into account diverse older adults' needs and experiences in crisis contexts.

关键词： Barcelona COVID-19 pandemic Digital social connectedness Entertainment Older adult resilience Public digital service

Prevalence of Helicobacter pylori infection among patients with esophageal carcinoma

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2024年第29期30卷 3479-3487页

作者： Miriam lópez-Gómez Maria Morales Rebeca Fuerte Marta Muñoz Pedro-David Delgado-lópez Jorge Francisco Gómez-Cerezo Enrique Casado Department of Medical Oncology Precision Oncology LaboratoryInfanta Sofía University HospitalSan Sebastián de los Reyes 28231MadridSpain Department of Medical Oncology Infanta Sofía University HospitalSan Sebastián de los Reyes 28702Spain Department of Internal Medicine Infanta Sofía University HospitalSan Sebastián de los Reyes 28703MadridSpain Department of Pathology Infanta Sofía University HospitalSan Sebastián de los Reyes 28702Spain Department of Neurosurgery Burgos University HospitalBurgos 09006Spain Department of Internal Medicine Infanta Sofía University Hospital and Henares University Hospital Foundation for Biomedical Research and InnovationSan Sebastian de los Reyes 28702MadridSpain Department of Medical Oncology Infanta Sofia University Hospital and Henares University Hospital Foundation for Biomedical Research and InnovationSan Sebastian de los Reyes 28702MadridSpain

BACKGROUND Helicobacter pylori(***)is a widespread microorganism related to gastric adenocarcinoma(AC).In contrast,it has been reported that an inverse association exists between *** infection and esophageal *** mechanisms underlying this supposedly protective effect remain *** To determine the prevalence of *** infection in esophageal carcinoma patients,we performed a retrospective observational study of esophageal tumors diagnosed in our *** We retrospectively reviewed the prevalence of *** infection in a cohort of patients diagnosed with esophageal *** or previous proton pump inhibitor(PPI)usage was also *** A total of 89 patients with esophageal carcinoma(69 males,77.5%),with a mean age of 66 years(range,26-93 years)were *** was the most frequent pathological variant(n=47,52.8%),followed by squamous cell carcinoma(n=37,41.6%).Fourteen ACs(29.8%)originated in the gastroesophageal junction and 33(70.2%)in the esophageal ***,54 patients(60.7%)presented at stages III and *** *** infection occurred only in 4 patients(4.5%),3 with AC(6.3%of all ACs)and 1 with squamous cell carcinoma(2.7%of all squamous cell tumors).All patients with previous *** infection had stage *** one patient had received prior *** eradication therapy,whereas 86(96.6%)had received previous or concomitant PPI *** In our cohort of patients,and after histologic evaluation of paraffin-embedded primary tumors,we found a very low prevalence of previous *** *** also reviewed the medical history of the patients,concluding that the majority had received or were on PPI *** minimal prevalence of *** infection found in this cohort of patients with esophageal carcinoma suggests a protective role.

关键词： Helicobacter pylori Eradication Esophageal tumor Dysbiosis Proton pump inhibitors Carcinogenesis Microbiota Incidence