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Using fused filament fabrication to improve the tribocorrosion behaviour of 17-4 PH SS in comparison to other metal forming techniques

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Friction 2024年第10期12卷 2325-2343页

作者： Cristina garcÍA-CABEZÓn Juan Alfonso nARAnJO Celia garcÍA-HERnÁnDEZ Cristina BERGES Gemma HERRAnZ Fernando MARTÍn-PEDROSA Materials Engineering E.I.I.Universidad de ValladolidValladolid 47011Spain InEI-Escuela Técnica Superior de Ingeniería Industrial(ETSII) Universidad de Castilla La ManchaCastilla-La Mancha 13071Spain

Fused filament fabrication(FFF)is one of the additive manufacturing processes which has gained more interest because of its simplicity and *** technology is similar to the conventional metal injection moulding(MIM)process,consisting of the feedstock preparation of metal powder and polymer binders,followed by layer-by-layer 3D printing(FFF)or injection(MIM)to create green parts and,finally,debinding and ***,both technologies provide near-dense *** work presents an in-depth study of the processing method’s *** porosity,microstructure,hardness,corrosion,and tribocorrosion behaviour are compared for 17-4 PH SS samples processed from powder by additive manufacturing using FFF and MIM,as well as conventional powder metallurgy(PM)*** samples exhibited the highest macro and microhardness,while corrosion behaviour was similar for both MIM and FFF samples,but superior in comparison to conventional PM ***,the FFF-as fabricated samples displayed a significant improvement in tribocorrosion resistance that could be explained by the higher proportion of delta ferrite and retained austenite in their microstructure.

关键词： 17-4 PH SS fused filament fabrication(FFF) metal injection moulding(MIM) corrosion behaviour powder metallurgy(PM) tribocorrosion behaviour

Influence of biomass burning on ozone levels in the Megalopolis of Central Mexico during the COVID-19 lockdown

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Journal of Environmental Sciences 2024年第9期143卷 99-115页

作者： Victor Almanza Luis Gerardo Ruiz-Suárez Ricardo Torres-Jardón Agustín garcía-Reynoso Iván Y.Hernández-Paniagua Institute for Atmospheric Sciences and Climate Change National Autonomous University of MexicoCoyoacan 04510Mexico CityMexico

The massive reductions in anthropogenic emissions resulting from the COVID-19 lockdown provided a unique opportunity to evaluate the effect of mitigation measures aiming to abate air *** Mexico,the total lockdown period took place during the dry-hot season when biomass burning activity is ***,we investigate the role of biomass burning emissions on regional ozone levels in the Megalopolis of Central *** studied period covers the lockdown phases 2 and 3,and the first month of the new *** applied a factor separation technique and process analysis to estimate the pure and synergistic contributions of emission reductions under lockdown and that from biomass burning to daily ozone maximum concentrations in 7 metropolitan areas of different states in the *** results revealed that biomass burning plumes likely masked the effect of massive reductions from mobile emissions,impacted the PBL development during phase 3 and favored transition and mixed nO_(x)-limited and VOC-limited regional *** contributed to increased ozone production in the middle to lower PBL by changing the regional background levels which potentially could bias high ozone production efficiency *** the Megalopolis contribution to economic and societal development at national scale,our study suggests that ozone mitigation measures during the dry-hot season targeting mainly mobile emissions will likely be offset by biomass burning plumes.A regional and synergic policy aiming to control biomass burning would help to reduce the occurrence of high ozone levels in Central Mexico with the co-benefit of tackling short-lived climate pollutants.

关键词： COVID-19 Mexico Megalopolis Ozone Factor Separation Process Analysis

Robust hybrid bismuth perovskites as potential photocatalysts for overall water splitting

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nano Research 2024年第5期17卷 4593-4601页

作者： Antonio J.Chacón-garcía Herme G.Baldovi Artem A.Babaryk Antonio Rodríguez-Diéguez Sergio navalón Yolanda Pérez Hermenegildo garcía Patricia Horcajada Advanced Porous Materials Unit IMDEA Energy InstituteAvda.Ramón y Cajal 328935 MóstolesMadridSpain Departamento de Química Universitat Politècnica de València46022 ValènciaSpain Departamento Química Inorgánica Universidad de Granada1807GranadaSpain Departamento de Biología y Geología Física y Química Inorgánica.ESCET.Universidad Rey Juan Carlos28933 MóstolesMadridSpain Instituto de tecnología química CSIC-UPV Universitat Politècnica de València(UPV)46022Spain

Organic-inorganic hybrid perovskites have gained great attention as promising photocatalysts for hydrogen ***,due to their poor stability in water,the use of aqueous hydrohalic acid solutions is specifically required for an efficient hydrogen ***,three novel photoactive lead-free hybrid perovskites based on bismuth and triazolium cations(denoted as IEF-15,IEF-16,and IEF-17(IEF stands for IMDEA energy frameworks))were synthesized and fully characterized(structural,compositional,optical,etc.).Further,these solids were proposed as photocatalysts for the challenging gas phase overall water splitting(OWS)***,IEF-16 thin films exhibited a remarkable photocatalytic activity in both H_(2) and O_(2) evolution,as a consequence of its appropriate bandgap and energy-band alignment,achieving hydrogen evolution rates ofμmol·g_(H_(2))^(-)1846 and 360 after 24 h under ultraviolet-visible(UV-vis)irradiation or simulated solar irradiation,*** study additionally highlights the remarkable structural and photochemical stability of IEF-16 under different operational conditions(*** volume,irradiation and temperature),paving the way for green hydrogen production from OWS using perovskite-based photocatalysts.

关键词： bismuth-based hybrid perovskites thin films photocatalysis overall water splitting green hydrogen

Endoscopic treatment of biliopancreatic pathology in patients with Whipple's pancreaticoduodenectomy surgical variants: Lessons learned from single-balloon enteroscopy-assisted ERCP

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 509-514页

作者： Rodrigo garcés-Durán Laurent Monino Pierre H Deprez Hubert Piessevaux Tom G Moreels Department of Gastroenterology and Hepatology Universitécatholique de LouvainCliniques Universitaires Saint-LucAvenue Hippocrates 101200 BrusselsBelgium

Background: Endoscopic treatment of biliopancreatic pathology is challenging due to surgically altered anatomy after Whipple's pancreaticoduodenectomy. This study aimed to evaluate the feasibility and safety of single-balloon enteroscopy-assisted endoscopic retrograde cholangiopancreatography(SBE-ERCP) to treat biliopancreatic pathology in patients with Whipple's pancreaticoduodenectomy surgical variants. Methods: We retrospectively analyzed 106 SBE-ERCP procedures in 46 patients with Whipple's variants. Technical and clinical success rates and adverse events were evaluated. Results: Biliary SBE-ERCP was performed in 34 patients and pancreatic SBE-ERCP in 17, including 5 with both indications. From a total of 106 SBE-ERCP procedures, 76 were biliary indication with technical success rate of 68/76(90%) procedures and clinical success rate of 30/34(88%) patients. Mild adverse event rate was 8/76(11%), without serious adverse events. From a total of 106 SBE-ERCP procedures, 30 were pancreatic indication with technical success rate of 24/30(80%) procedures( P = 0.194 vs. biliary SBEERCP) and clinical success rate of 11/17(65%) patients( P = 0.016 vs. biliary SBE-ERCP). Mild adverse event rate was 6/30(20%)( P = 0.194 vs. biliary SBE-ERCP), without serious adverse events. After SBE-ERCP failure, endoscopic ultrasound-guided drainage, percutaneous drainage and redo surgery were alternative therapeutic options. Conclusions: Biliopancreatic pathology after Whipple's pancreaticoduodenectomy variants can be treated using SBE-ERCP without serious adverse events. Technical and clinical success rates are high for biliary indications, whereas clinical success rate of pancreatic indications is significantly lower. SBE-ERCP can be considered as first-line treatment option in this patient group with surgically altered anatomy.

关键词： Enteroscopy Endoscopic retrograde cholangiopancreatography Pancreaticoduodenectomy Surgically altered anatomy Whipple’s procedure

How inflammation influences psychiatric disease

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World Journal of Psychiatry 2024年第3期14卷 342-349页

作者： Eduardo Ferat-Osorio JoséLuis Maldonado-garcía Lenin Pavón División de Investigación Clínica de la Coordinación de Investigación en Salud Instituto Mexicano del Seguro SocialMexico City 06720Mexico Departamento de Bioquímica Facultad de MedicinaUniversidad Nacional Autónoma de MéxicoCoyoacán 04510Ciudad de MéxicoMexico Departamento de Inmunología Escuela Nacional de Ciencias BiológicasInstituto Politécnico NacionalMexico City 11340Mexico Laboratorio de Psicoinmunología Instituto Nacional de Psiquiatría Ramón de la Fuente MuñizMexico City 14370Mexico

Recent studies highlight the strong correlation between infectious diseases and the development of neuropsychiatric *** this editorial,we comment on the article“Anti-infective therapy durations predict psychological stress and laparoscopic surgery quality in pelvic abscess patients”by Zhang et al,published in the recent issue of the World Journal of Psychiatry 2023;13(11):*** discussion highlighted the potential consequences of anxiety,depression,and psychosis,which are all linked to bacterial,fungal,and viral infections,which are relevant to the impact of inflammation on the sequelae in mental health as those we are observing after the coronavirus disease 2019 *** focus specifically on the immune mechanisms triggered by inflammation,the primary contributor to psychiatric ***,pathophysiological mechanisms such as organ damage,post-injury inflammation,and infectioninduced endocrine alterations,including hypocortisolism or autoantibody formation,significantly contribute to the development of chronic low-grade inflammation,promoting the emergence or development of psychiatric alterations in susceptible *** inflammation can have long-term effects on patients,a multidisciplinary treatment plan can avoid complications and debilitating health issues,and it is crucial to recognize and address the mental health implications.

关键词： Inflammation infection Depression Pelvic inflammatory disease Psychiatric complication

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

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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

Morphometry and Mineral Content in the Seeds and Soil of Two Species of Argemone L.(Papaveraceae)in the Central Part of the Chihuahuan Desert

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Phyton-International Journal of Experimental Botany 2024年第2期93卷 371-386页

作者： Perla Patricia Ochoa-garcía Jaime Sánchez-Salas Ricardo Trejo-Calzada Jesús JosafathQuezada-Rivera Fabián garcía-González Unidad Regional Universitaria de ZonasÁridas BermejilloUniversidad Autónoma ChapingoDurango35230México Facultad de Ciencias Biológicas Universidad Juárez del Estado de DurangoGómez PalacioDurango35010México

The genus Argemone L.(Papaveraceae)is found widely distributed in Mexico’s Chihuahuan Desert(CD).Some species of this genus are of phytochemical or ethnobotanical *** are inedible plants considered as *** date they have not been broadly studied;thus,their ecology is,to our knowledge,*** present work was centered around carrying out a morphometric analysis and the determination of minerals in the soil and seeds of the wild populations of Argemone at sites belonging to two ecoregions of the CD in *** April 2021 and April 2022,seeds of Argemone spp.,and soil samples were collected at 10 sites of the *** seeds were selected under a randomized design,and weight,length,diameter,thickness,buoyancy,and mineral content were *** soil samples were obtained under the Mexican regulation nOM-021-RECnAT-2000,and determinations of mineral content,electrical conductivity,apparent density,and soluble anions were *** information obtained was grouped by variable,species,and place of *** statistical tests consisted of an AnOVA,Tukey means tests considering p≤0.05,and a Principal Components *** pleiacantha exhibited differences in terms of weight(F=54.79,p=0.001),length(F=90.83,p=0.001),thickness(F=104.89,p=0.001),and diameter(F=155.82,p=0.001),and the differences in Argemone mexicana were in weight(F=46.71,p=0.001),thickness(F=187.49,p=0.001),length(F=191.56,p=0.001),and diameter(F=215.83,p=0.001).The evaluated seeds reached their maximal imbibition velocity at 24 h of *** content of the micro-and macro-nutrients analyzed in the seeds and soil suggest a tight relation with the morphometric characteristics of the seeds.

关键词： Micronutrients agricultural area semiarid zone ecoregion buoyancy

Global paleobiogeography of Albian—Cenomanian(mid-Cretaceous)marine ostracods

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Journal of Palaeogeography 2024年第2期13卷 212-236页

作者： Bernardo Vázquez-garcía Jorge Villegas-Martín Gerson Fauth Leonardo Borghi Aristóteles De Moraes Rios netto Post-Graduate Program in Geology Unisinos UniversitySao LeopoldoRSBrazil Technological Institute of Paleoceanography and Climate Change-Itt Oceaneon Unisinos UniversitySao LeopoldoRSBrazil Laboratory of Sedimentary Geology(Lagesed) Department of GeologyInstitute of GeosciencesUFRJ-Federal Universityof Riode JaneiroBrazil Labmicro Department of GeologyInstitute of GeosciencesUFRJ-Federal University of Rio de JaneiroBrazil

Despite their potential for providing important information for paleobiogeography,studies using ostracod assemblages compiled from global datasets have been scarce so *** this study,the paleogeographic implications of the relationship between different ostracod assemblages are analyzed and discussed for the Albian and *** compiled an ostracod dataset at the genus level,with 168 genera for the Albian and 174 for the Cenomanian,to which different multivariate statistical methods of grouping were *** affinity between different ostracod assemblages from different regions allowed for the delineation of 30 operational geographic units(OGUs)for the Albian,and 32 OGUs for the Cenomanian,grouped in three paleobiogeographic units(PBUs;Megatethys,Persia,and Austral)and one sub-unit(PBSU;Maghreb associated to the Megatethys).The Maghreb PBSU showed minor changes between the Albian and *** relationship among the OGUs grouped in each PBU is related to different factors,such as eustatic sea level events,similar climatic zones,and marine current circulation patterns.A relationship was observed between the Gabon and nigeria OGUs with the Persia PBU,which suggests a direct east—west connection between them during the *** affinity observed in the Austral PBU between the South American,South African,and Australian regions during the Albian can be explained by their relative geographic isolation due to the Walvis Ridge *** eventual flooding of this barrier led to the relationship observed between the SE Brazilian and Bolivian regions with the Austral ***,the data also suggested that the separation of the Indian subcontinent from the Austral PBU took place during the Cenomanian.

关键词： Operational geographic units Paleobiogeographic units Albian Cenomanian Marine ostracods

Chebyshev polynomial-based Ritz method for thermal buckling and free vibration behaviors of metal foam beams

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 891-910页

作者： n.D.nGUYEn T.n.nGUYEn Faculty of Civil Engineering Ho Chi Minh City University of Technology and EducationHo Chi Minh City 71309Viet Nam Faculty of Engineering and Technology Kien Giang UniversityChau Thanh 92000Viet Nam

This study presents the Chebyshev polynomials-based Ritz method to examine the thermal buckling and free vibration characteristics of metal foam *** analyses include three models for porosity distribution and two scenarios for thermal *** material properties are assessed under two conditions,i.e.,temperature dependence and temperature *** theoretical framework for the beams is based on the higher-order shear deformation theory,which incorporates shear deformations with higher-order *** governing equations are established from the Lagrange equations,and the beam displacement fields are approximated by the Chebyshev *** simulations are performed to evaluate the effects of thermal load,slenderness,boundary condition(BC),and porosity distribution on the buckling and vibration behaviors of metal foam *** findings highlight the significant influence of temperature-dependent(TD)material properties on metal foam beams'buckling and vibration responses.

关键词： Ritz method Chebyshev function buckling vibration metal foam beam higher-order beam theory(HOBT)