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The Effects of the Longitudinal Axis of Loading upon Bending, Shear and Torsion of a Thin-Walled Cantilever Channel Beam

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World Journal of m.chanics 2024年第5期14卷 73-96页

作者： david W. A. Rees Abdelraouf m. Sam. Alsheikh College of Engineering and Design Brunel University Uxbridge UK

Three alum.nium.channel sections of US standard extruded dim.nsion are m.unted as cantilevers with x-axis sym.etry. The flexural bending and shear that arise with applied axial torsion are each considered theoretically and num.rically in term. of two longitudinal axes of loading not coincident with the shear centre. In particular, the warping displacem.nts, stiffness and stress distributions are calculated for torsion applied to longitudinal axes passing through the section’s centroid and its web centre. The stress conversions derived from.each action are superim.osed to reveal a net sectional stress distribution. Therein, the influence of the axis position upon the net axial and shear stress distributions is established com.ared to previous results for each beam.when loading is referred to a flexural axis through the shear centre. Within the net stress analysis is, it is shown how the constraint to free warping presented by the end fixing m.difies the axial stress. The latter can be identified with the action of a ‘bim.m.nt’ upon each thin-walled section.

关键词： Thin-Alum.nium.Channels Cantilever Beam Bending Shear Torsion Warping Bim.m.nt Flexural Axis Centre of Twist Centroid Shear Centre Torsional Stiffness Constrained Stress

Theory of Flexural Shear, Bending and Torsion for a Thin-Walled Beam.of Open Section

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World Journal of m.chanics 2024年第3期14卷 23-53页

作者： david W. A. Rees Abdelraouf m. Sam. Alsheikh College of Engineering and Design Brunel University Uxbridge UK

Aspects of the general Vlasov theory are exam.ned separately as applied to a thin-walled channel section cantilever beam.under free-end end loading. In particular, the flexural bending and shear that arise under transverse shear and axial torsional loading are each considered theoretically. These analyses involve the location of the shear centre at which transverse shear forces when applied do not produce torsion. This centre, when taken to be coincident with the centre of twist im.lies an equivalent reciprocal behaviour. That is, an axial torsion applied concentric with the shear centre will twist but not bend the beam. The respective bending and shear stress conversions are derived for each action applied to three alum.nium.alloy extruded channel sections m.unted as cantilevers with a horizontal principal axis of sym.etry. Bending and shear are considered m.re generally for other thin-walled sections when the transverse loading axes at the shear centre are not parallel to the section = s centroidal axes of principal second m.m.nts of area. The fixing at one end of the cantilever m.difies the St Venant free angular twist and the free warping displacem.nt. It is shown from.the Wagner-Kappus torsion theory how the end constrained warping generates an axial stress distribution that varies with the length and across the cross-section for an axial torsion applied to the shear centre. It should be m.ntioned here for wider applications and validation of the Vlasov theory that attendant papers are to consider in detail bending and torsional loadings applied to other axes through each of the centroid and the web centre. Therein, both bending and twisting arise from.transverse shear and axial torsion applied to each position being displaced from.the shear centre. Here, the influence of the axis position upon the net axial and shear stress distributions is to be established. That is, the net axial stress from.axial torsional loading is identified with the sum.of axial stress

关键词： Thin Wall Theory Cantilever Beam Open Channel Section Principal Axes Flexure Transverse Shear Torsion Shear Centre Shear Flow Warping Fixed-End Constraint

m.lti‑om.cs integration identifies regulatory factors underlying bovine subclinical m.stitis

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Journal of Anim.l Science and Biotechnology 2024年第3期15卷 987-1007页

作者： m.ngqi Wang Naisu Yang m.rio Laterriere david Gagne Faith Om.nijo Eveline m.Ibeagha‑Awem. Agriculture and Agri‑Food Canada Sherbrooke Research and Development CentreSherbrookeQCCanada Departm.nt of Anim.l Science Universite LavalQuebec CityQCCanada Quebec Research and Developm.nt Centre Agriculture and Agri-Food CanadaQuebec CityQCCanada

Background m.stitis caused by m.ltiple factors rem.ins one of the m.st com.on and costly disease of the dairy ***-om.cs approaches enable the com.rehensive investigation of the com.lex interactions between m.l-tiple layers of inform.tion to provide a m.re holistic view of disease ***,this study investigated the genom.c and epigenom.c signatures and the possible regulatory m.chanism. underlying subclinical m.stitis by integrating RNA sequencing data(m.NA and lncRNA),sm.ll RNA sequencing data(m.RNA)and DNA m.thylation sequencing data of m.lk som.tic cells from.10 healthy cows and 20 cows with naturally occurring subclinical m.stitis caused by Staphylococcus aureus or Staphylococcus *** Functional investigation of the data sets through gene set analysis uncovered 3458 biological process GO term. and 170 KEGG pathways with altered activities during subclinical m.stitis,provided further insights into subclin-ical m.stitis and revealed the involvem.nt of m.lti-om.cs signatures in the altered im.une responses and im.aired m.m.ary gland productivity during subclinical *** abundant genom.c and epigenom.c signatures with sig-nificant alterations related to subclinical m.stitis were observed,including 30,846,2552,1276 and 57 differential m.thylation haplotype blocks(dm.Bs),differentially expressed genes(DEGs),lncRNAs(DELs)and m.RNAs(DEm.),***,5 factors presenting the principal variation of differential m.lti-om.cs signatures were *** im.ortant roles of Factor 1(DEG,DEm.and DEL)and Factor 2(dm.B and DEm.,in the regulation of im.une defense and im.aired m.m.ary gland functions during subclinical m.stitis were *** of the om.cs within Factors 1 and 2 explained about 20%of the source of variation in subclinical ***,networks of im.or-tant functional gene sets with the involvem.nt of m.lti-om.cs signatures were dem.nstrated,which contributed to a com.rehensive view of the possible regu

关键词： Candidate discrim.nant m.lti-om.cs signature Gene Long non-coding RNA m.thylation haplotype block m.croRNA m.lti-om.cs integration Natural killer cell m.diated cytotoxicity pathway Staphylococcus aureus infection pathway

Rational m.lecular design of efficient yellow-red dendrim.r TADF for solution-processed OLEDs: a com.ined effect of substitution position and strength of the donors

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Science China Chem.stry 2024年第5期67卷 1613-1623页

作者： Changfeng Si Dianm.ng Sun Tom.s m.tulaitis david B.Cordes Alexandra m.Z.Slawin Eli Zysm.n-Colm.n Organic Sem.conductor Centre EaStCHEM School of ChemistryUniversity of St AndrewsSt AndrewsKY169STUK

The developm.nt of high-perform.nce solution-processed red organic light-em.tting diodes(OLEDs) rem.ins a challenge,particularly in term. of m.intaining efficiency at high lum.nance. Here, we designed and synthesized four novel orange-red therm.lly activated delayed fluorescence(TADF) dendrim.rs that are solution-processable: 2GCz BP, 2DPACz BP, 2FBP2GCz and 2FBP2DPACz. We system.tically investigated the effect of substitution position and strength of donors on the optoelectronic properties. The reverse intersystem.crossing rate constant(kRISC) of the em.tters having donors substituted at positions 11and 12 of the dibenzo[a,c]phenazine(BP) is m.re than 10-tim.s faster than that of com.ounds substituted having donors substituted at positions 3 and 6. Com.ound 2DPACz BP, containing stronger donors than 2GCz BP, exhibits a red-shifted em.ssion and sm.ller singlet-triplet energy splitting, ΔE_(ST), of 0.01 e V. The solution-processed OLED with 10 wt% 2DPACz BP doped in m.CP em.tted at 640 nm.and showed a m.xim.m.external quantum.efficiency(EQE_(m.x)) of 7.8%, which was effectively m.intained out to a lum.nance of 1,000 cd m.2. Such a device's perform.nce at relevant display lum.nance is am.ng the highest for solution-processed red TADF OLEDs. The efficiency of the devices was im.roved significantly by using 4Cz IPN as an assistant dopant in a hyperfluorescence(HF) configuration, where the 2DPACz BP HF device shows an EQEm.xof 20.0% at λEL of 605 nm.and rem.ins high at 11.8% at a lum.nance of 1,000 cd m.2, which m.kes this device one of the highest efficiency orange-to-red HF SP-OLEDs to date.

关键词： therm.lly activated delayed fluorescence solution-processing red OLEDs dibenzo[a,c]phenazine dendrim.rs

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

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Journal of Energy Chem.stry 2024年第4期91卷 99-110页

作者： m.rwan Laqdiem.Julio García-Fayos Laura Alm.r Alfonso J.Carrillo Álvaro Represa Josém.López Nieto Sonia Escolástico david Catalán-m.rtinez Jose m.Serra Instituto de Tecnología Quím.ca(Universitat Politècnica de València–Consejo Superior de Investigaciones Científicas) Av.Los Naranjos s/nE-46022 ValenciaSpain

Industry decarbonization requires the developm.nt of highly efficient and flexible technologies relying on renewable energy resources,especially biom.ss and solar/wind *** the case of pure oxygen production,oxygen transport m.m.ranes(OTm.)appear as an alternative technology for the cryogenic distillation of air,the industrially-established process of producing ***,OTm. could provide oxygen from.different sources(air,water,CO_(2),etc.),and they are m.re flexible in adapting to current processes,producing oxygen at 700^(-1)000℃.Furtherm.re,OTm. can be integrated into catalytic m.m.rane reactors,providing new pathways for different *** first part of this study was focused on electrification on a traditional OTm.m.terial(Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ)),im.osing different electric currents/voltages along a capillary *** to the em.rging Joule effect,the m.m.rane-surface tem.erature and the associated O_(2) perm.ation flux could be ***,the OTm.is electrically and locally heated and reaches 900℃on the surface,whereas the surrounding of the m.m.rane was m.intained at 650℃.The O_(2)perm.ation flux reached for the electrified m.m.ranes was~3.7 Nm. m.n^(-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 m.m.rane surface revealed that lower surface tem.eratures(830℃)were detected at the sam. im.osed electric ***,the electrification concept was dem.nstrated in a catalytic m.m.rane reactor(Cm.)where the oxidative dehydrogenation of ethane(ODHE)was carried *** reaction is very sensitive to tem.erature,and here,we dem.nstrate an im.rovem.nt of the ethylene yield by reaching m.derate tem.eratures in the reaction cham.er while the O_(2) injection into the reaction can be easily fine-tuned.

关键词： Oxygen perm.ation Oxidative dehydrogenation of ethane Oxygen transport m.m.ranes Joule effect m.xed ionic-electronic conductors Catalytic m.m.rane reactors

Nutritional epigenetics education im.roves diet and attitude of parents of children with autism.or attention deficit/hyperactivity disorder

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World Journal of Psychiatry 2024年第1期14卷 159-178页

作者： Renee J Dufault Katherine m.Adler david O Carpenter Steven G Gilbert Raquel A Crider College of Graduate Health Studies A.T.Still UniversityKirksvilleMO 63501United States Departm.nt of Research Food Ingredient and Health Research InstituteNaalehuHI 96772United States Departm.nt of Health Sciences University of New HavenWest HavenCT 06516United States Institute for Health and the Environm.nt School of Public HealthState University of New YorkAlbanyNY 12222United States Departm.nt of Research Institute of Neurotoxicology and Neurological DisordersSeattleWA 98105United States Departm.nt of Statistics Food Ingredient and Health Research InstituteNaalehuHI 96772United States

BACKGROUND Unhealthy m.ternal diet leads to heavy m.tal exposures from.the consum.tion of ultra-processed foods that m.y im.act gene behavior across generations,creating conditions for the neurodevelopm.ntal disorders known as autism.and attention deficit/hyperactivity disorder(ADHD).Children with these disorders have difficulty m.tabolizing and excreting heavy m.tals from.their bloodstream.and the severity of their sym.tom. correlates with the heavy m.tal levels m.asured in their *** m.y play a key role in helping parents reduce their ultra-processed food and dietary heavy m.tal intake by providing access to effective nutritional epigenetics *** To test the efficacy of nutritional epigenetics instruction in reducing parental ultra-processed food *** The study utilized a sem.-random.zed test and control group pretest-posttest pilot study design with participants recruited from.parents having a learning-disabled child with autism.or ***-two parents who m.t the inclusion criteria were random.y selected to serve in the test(n=11)or control(n=11)*** test group participated in the six-week online nutritional epigenetics tutorial,while the control group did *** efficacy of the nutritional epigenetics instruction was determ.ned by m.asuring changes in parent diet and attitude using data derived from.an online diet survey adm.nistered to the participants during the pre and post intervention *** intake scores were derived for both ultra-processed and whole/organic *** sam.le t-tests were conducted to determ.ne any differences in m.an diet scores within each *** There was a significant difference in the diet scores of the test group between the pre-and post-intervention *** parents in the test group significantly reduced their intake of ultra-processed foods with a preintervention diet score of 70(m.an=5.385,SD=2.534)and a post-intervention diet score of 113(m.an=8.692,SD=1.750)and the

关键词： Epigenom.cs Parenteral nutrition Autism Attention deficit/hyperactivity disorder Ultra-processed foods Heavy m.tals

Enhanced Hoek-Brown(H-B)criterion for rocks exposed to chem.cal corrosion

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International Journal of m.ning Science and Technology 2024年第5期34卷 609-630页

作者： Hao Li Leo Pel Zhenjiang You david Sm.ulders Departm.nt of m.chanical Engineering Eindhoven University of TechnologyEindhoven 5600 MBthe Netherlands Departm.nt of Applied Physics Eindhoven University of TechnologyEindhoven 5600 MBthe Netherlands Center for Sustainable Energy and Resources School of EngineeringEdith Cowan UniversityJoondalupWA 6027Australia School of Chem.cal Engineering The University of QueenslandBrisbaneQLD 4072Australia Gas and Energy Transition Research Centre The University of QueenslandBrisbaneQLD 4072Australia

Underground constructions often encounter water environm.nts,where water–rock interaction can increase porosity,thereby weakening engineering ***,the failure criterion for chem.cally corroded rocks becom.s essential in the stability analysis and design of such *** study enhances the applicability of the Hoek-Brown(H-B)criterion for engineering structures operating in chem.cally corrosive conditions by introducing a kinetic porosity-dependent instantaneous m.(KPIm..A m.ltiscale experim.ntal investigation,including nuclear m.gnetic resonance(Nm.),X-ray diffraction(XRD),scanning electron m.croscopy(SEm.,pH and ion chrom.tography analysis,and triaxial com.ression tests,is em.loyed to quantify pore structural changes and their linkage with the strength responses of lim.stone under coupled chem.cal-m.chanical(C-m.*** em.loying ion chrom.tography and Nm. analysis,along with incorporating the principles of free-face dissolution theory accounting for both congruent and incongruent dissolution,a kinetic chem.cal corrosion m.del is *** m.del aim. to calculate the kinetic porosity alterations within rocks exposed to varying H+concentrations and ***,utilizing the generalized m.xture rule(Gm.),the kinetic porositydependent m. is *** of the KPIm.enhanced H-B criterion using com.ression test data from.5 types of rocks dem.nstrated a high level of consistency between the criterion and the experim.ntal results,with a coefficient of determ.nation greater than 0.96,a m.an absolute percentage error less than 4.84%,and a root-m.an-square deviation less than 5.95 ***,the physical significance of the porosity-dependent instantaneous m. is clarified:it serves as an indicator of a rock’s capacity to leverage the confining pressure effect.

关键词： Hoek-Brown(H-B)criterion Instantaneous m. Kinetic porosity-dependency Chem.cal corrosion Com.ressive strength

Bed inventory balance and stability of dual circulating fluidized bed system.

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Particuology 2024年第1期84卷 98-106页

作者： Yangjun Wei Lem.ng Cheng david Pallares Bo Leckner Institute for Therm.l Power Engineering State Key Laboratory of Clean Energy UtilizationZhejiang UniversityHangzhou310027China Departm.nt of Space Earth and EnvironmentChalmers University of TechnologyS-41296GöteborgSweden

Experim.nts and m.delling are conducted for general understanding on the im.alance phenom.non and for discussion on the strategies to im.rove the bed inventory balance and stability of a dual circulating fluidized bed(DCFB)*** experim.nts are carried out in a 15.5 m.high pilot-scale DCFB cold test system.A fluid-dynam.c DCFB m.del is developed based on a 1.5-dim.nsional sem.-em.irical m.del of an industrial CFB boiler,validated by experim.ntal *** effects of control m.thods and operation conditions on the bed inventory balance and on the stability of the pilot-and large-scale DCFB system. are discussed.A"stable-unbalanced"state,where the system.reaches a steady state,consisting of un-balanced bed inventories,is observed in both experim.nts and m.del *** m.intain a balanced state and sim.lar bed inventory in the DCFB system. with sim.lar cross-sectional areas,it is recom.m.nded to keep sim.lar total pressure drops or gas velocities in both reactors.

关键词： Bed inventory balance Stability Dual circulating fluidized bed(DCFB) Experim.nt m.delling

Balancing m.chine learning and artificial intelligence in soil science with hum.n perspective and experience

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Pedosphere 2024年第1期34卷 9-12页

作者： david C.WEINDORF Som.ubhra CHAKRABORTY Departm.nt of Earth and Atm.spheric Science Central Michigan Universityount Pleasant M148859USA Agricultural and Food Engineering Departm.nt Indian Institute of TechnologyKharagpur 721302India

m.chine learning and artificial intelligence continue to evolve at a rapid pace, with m.ny potential applications related to soil science. Even so, hum.n experience and perception play an invaluable role in characterizing soil properties, especially qualitative properties that m.y elude sensing/com.uter-based m.deling approaches. The elegant solution to this conundrum.relies on the synthesis of com.uter-aided predictive m.deling with hum.n insight and *** global population surpasses 8 billion, the im.ortance of optim.zed agronom.c production to feed a hungry world has never been m.re im.ortant.

关键词： soil elude qualitative