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A Comprehensive Investigation on Shear Performance of Improved Perfobond Connector

Structural Durability & health Monitoring 2024年第3期18卷 299-320页

作者： Caiping huang zihan huang Wenfeng You School of Civil Engineering Architecture and EnvironmentHubei University of TechnologyWuhan430068China

This paper presents an easily installed improved perfobond connector (PBL) designed to reduce the shearconcentration of PBL. The improvement of PBL lies in changing the straight penetrating rebar to the z-typepenetrating rebar. To study the shear performance of improved PBL, two PBL test specimens which containstraight penetrating rebar and six improved PBL test specimens which contain z-type penetrating rebars weredesigned and fabricated, and push-out tests of these eight test specimens were carried out to investigate andcompare the shear behavior of PBL. Additionally, Finite Element Analysis (FEA) models of the PBL specimenswere established and validated against the test results. Through FEA, the effects of concrete grade, perforatedplate’s aperture, z-type penetrating rebar’s diameter, z-type penetrating rebar’s bending angle, and bending lengthon shear behaviors were discussed. The results indicate that (1) Compared with PBL specimens with straightpenetrating rebars, z-type penetrating rebar can significantly improve the shear resistance and shear stiffnessof the specimens. This enhanced performance can be mainly attributed to the increased adhesion of the transverserebar. (2) By comparing the load-slip curve, the slip of PBL test specimens which contain straight penetratingrebar increases rapidly and the bearing capacity decreases rapidly after concrete craking, while the bearingcapacity of z-type penetrating rebar specimens decreases first and then increases gradually, showing betterductility. (3) The stress of the PBL shear connector with z-type penetrating rebar is more uniform than thePBL shear connector with straight penetrating rebar, and the overall deformation is more uniform. (4) The higherthe concrete grade, the higher the shear bearing capacity and the better ductility of the new PBL. Increasing theaperture of the perforated plate or the diameter of the rebar has a very limited effect on the improvement of theshear capacity of PBL. Through the system

关键词： PBL penetrating rebar push-out test load-slip curve shear capacity finite element analysis

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Associations of daily sedentary behavior,physical activity,and sleep with irritable bowel syndrome:A prospective analysis of 362,193 participants

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Journal of Sport and health Science 2024年第1期13卷 72-80页

作者： Xu Gao Sifan Tian Ninghao huang Gang Sun Tao huang Department of Occupational and Environmental health Sciences School of Public HealthPeking UniversityBeijing 100191China Department of Epidemiology and Biostatistics School of Public HealthPeking UniversityBeijing 100191China Department of Gastroenterology and hepatology First Medical Center of People's Liberation Army General HospitalBeijing 100853China

Background:Irritable bowel syndrome(IBS)substantially affects quality of life and requires early *** study aimed to elucidate the relationships between IBS and daily behaviors,including sedentary behavior(SB),physical activity(PA),and *** particular,it seeks to identify healthy behaviors to reduce IBS risk,which previous studies have rarely ***:Daily behaviors were retrieved from self-reported data of 362,193 eligible UK Biobank *** cases were determined by self-report or health care data according to RomeⅣ***:A total of 345,388 participants were IBS-free at baseline,during a median follow-up of 8.45 years,19,885 incident IBS cases were *** examined individually,SB and shorter(≤7 h/day)or longer(>7 h/day)sleep duration were each positively associated with increased IBS risk,and PA was associated with lower IBS *** isotemporal substitution model suggested that replacing SB with other activities could provide further protective effects against IBS *** people sleeping≤7 h/day,replacing 1 h of SB with equivalent light PA,vigorous PA,or sleep was associated with 8.1%(95%confidence interval(95%CI):0.901-0.937),5.8%(95%CI:0.896-0.991),and 9.2%(95%CI:0.885-0.932)reduced IBS risk,*** people sleeping>7 h/day,light and vigorous PA were associated with a 4.8%(95%CI:0.926-0.978)and a 12.0%(95%CI:0.815-0.949)lower IBS risk,*** benefits were mostly independent of genetic risk for ***:SB and unhealthy sleep duration are risk factors for IBS.A promising way to mitigate IBS risk for individuals sleeping≤7 h/day and for those sleeping>7 h/day appears to be by replacing SB with adequate sleep or vigorous PA,respectively,regardless of the genetic predisposition of IBS.

关键词： Irritable bowel syndrome Isotemporal substitution model Physical activity Sedentary behavior Sleep

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Fast efficient photon deceleration in plasmas by using two laser pulses at different frequencies

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Matter and Radiation at Extremes 2024年第3期9卷 11-18页

作者： Y.X.Wang X.L.zhu S.M.Weng P.Li X.F.Li h.Ai h.R.Pan z.M.Sheng Key Laboratory for Laser Plasmas(moe) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghai 200240China Research Center of Laser Fusion of China Academy of Engineering Physics MianyangSichuan 621900China State key Laboratory of high Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Tsung-dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

The generation of ultrashort high-power light sources in the mid-infrared(mid-IR)to terahertz(Thz)range is of interest for applications in a number of fields,from fundamental research to biology and *** conventional laser technology,photon deceleration in plasma wakes provides an alternative approach to the generation of ultrashort mid-IR or Thz ***,we present a photon deceleration scheme for the efficient generation of ultrashort mid-IR or Thz pulses by using an intense driver laser pulse with a relatively short wavelength and a signal laser pulse with a relatively long *** signal pulse trails the driver pulse with an appropriate time delay such that it sits at the front of the second wake bubble that is driven by the driver *** to its relatively long wavelength,the signal pulse will be subjected to a large gradient of the refractive index in the plasma wake ***,the photon deceleration in the plasma wake becomes faster and more efficient for signal pulses with longer *** greatly enhances the capacity and efficiency of photon deceleration in the generation of ultrashort high-power light sources in the long-wavelength IR and Thz spectral ranges.

关键词： laser ultrashort photon

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Access to high-Molecular-Weight Polyethylenes through high Temperature Ethylene Polymerization Catalysed by Ethylene-Bridged ansa-(3-R-Cyclopentadienyl)(Fluorenyl) zirconocene Complexes

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Chinese Journal of Polymer Science 2024年第1期42卷 42-51,I0007页

作者： Bo Li haiyan Ma Jiling huang Shanghai Key Laboratory of Functional Materials Chemistry and Laboratory of Organometallic Chemistry School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

A series of C1-symmetric ethylene-bridged ansa-(3-R-cyclopentadienyl)(fluorenyl) metallocene complexes(zr: 1-5;hf: 6) have been synthesized, characterized and investigated as catalyst precursors for the high temperature ethylene polymerization. Using methylaluminoxane(MAO) as the cocatalyst, zirconium complexes 1-5 bearing a bulky substituent on the 3-position of the cyclopendienyl ring showed high catalytic activities up to 1.48×10^(7) g PE·mol_(zr)^(-1)·h^(-1) toward the polymerization of ethylene and afforded polyethylenes with high molecular weights(1.49×10^(5)-6.31×10^(5) g/mol), meanwhile exhibting great thermal stability at high temperatures up to 120 ℃ together with a long catalytic life time up to 2 h. By adopting low Al/zr ratios, such as 125, polyethylenes with ultra high molecular weights up to 2.86×106 g/mol were obtained. It is worthy of noting that zirconium complexes 1-4 bearing a substituent with an aryl pendant showed temperature-dependent activities, which increased rapidly with the increase of polymerization temperature, thus weak interaction of the pendent aryl group with the cationic active center is proposed to account for the very low activities displayed at low temperatures. In contrast to zirconocene complexes 1-5, hafnocene complex 6 only displayed very low catalytic activities toward the polymerization of ethylene and afforded polyethylenes with molecular weights ten times smaller than those obtained by zirconocene complexes 1-5. zirconocene complexes 1-5 were also able to catalyse the polymerization of propylene at high temperatures, but only afforded waxes with low molecular weights.

关键词： ansa-Metallocene Ethylene Propylene Polymerization high temperature

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Efficient guiding and focusing of intense laser pulse using periodic thin slits

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Matter and Radiation at Extremes 2024年第4期9卷 29-39页

作者： L.Xu T.W.huang K.Jiang C.N.Wu h.Peng P.C.hen R.Li h.B.zhuo C.T.zhou Shenzhen Key Laboratory of Ultraintense Laser and Advanced Material Technology Center for Intense Laser ApplicationTechnologyand College of Engineering PhysicsShenzhen Technology UniversityShenzhen 518118People’s Republic of China

Slits have been widely used in laser-plasma interactions as plasma optical components for generating high-harmonic light and controlling laser-driven particle ***,we propose and demonstrate that periodic thin slits can be regarded as a new breed of optical elements for efficient focusing and guiding of intense laser *** fundamental physics of intense laser interaction with thin slits is studied,and it is revealed that relativistic effects can lead to enhanced laser focusing far beyond the pure diffractive focusing *** addition,the interaction of an intense laser pulse with periodic thin slits makes it feasible to achieve multifold enhancement in both laser intensity and energy transfer efficiency compared with conventional *** results provide a novel method for manipulating ultra-intense laser pulses and should be of interest for many laser-based applications.

关键词： laser pulse intense

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On hamiltonian Property of Cayley Digraphs

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 547-556页

作者： Fang DUAN Qiong-xiang huang School of Mathematics Science Xinjiang Normal UniversityUrumqi 830017China College of Mathematics and Systems Science Xinjiang UniversityUrumqi 830017China

Let G be a finite group generated by S and C(G,S) the Cayley digraphs of G with connection set *** this paper,we give some sufficient conditions for the existence of hamiltonian circuit in C(G,S),where G=zm×h is a semiproduct of zmby a subgroup h of *** particular,if m is a prime,then the Cayley digraph of G has a hamiltonian circuit unless G=zm×*** addition,we introduce a new digraph operation,called φ-semiproduct of Γ1by Γ2and denoted by Γ1×Γ_φΓ2,in terms of mapping φ:V(Γ2)→{1,-1}.Furthermore we prove that C(zm,{a})×_φ C(h,S) is also a Cayley digraph if φ is a homomorphism from h to{1,-1} ≤ zm~*,which produces some classes of Cayley digraphs that have hamiltonian circuits.

关键词： Cayley digraphs hamiltonian circuit external semidirect product

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Single-atom catalysis:a promising avenue for precisely controlling reaction pathways

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Frontiers of Chemical Science and Engineering 2024年第7期18卷 97-120页

作者： Xiaobo Yang Xuning Li Yanqiang huang State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Single-atom catalysts (SACs), characterized by exceptionally high atom efficiency, have garnered significant attention across various catalytic reactions. Recent studies have showcased SACs with robust capabilities for precise catalysis, specifically targeting reactions along designated pathways. This review focuses on the advances in the precise activation and reconstruction of chemical bonds on SACs, including precise activation of C–O and C–h bonds and selective couplings involving C–C and C–N bonds. Our discussion begins with a thorough exploration of the factors that render SACs skilled in precise catalytic processes, encompassing the narrow d-band electronic state of single atom site resulting in the adsorption tendency, isolate site resulting in unique adsorption structure, and synergy effect of a single atom site with its neighbors. Subsequently, we elaborate on the applications of SACs in electrocatalysis and thermocatalysis including four prominent reactions, namely, electrochemical CO_(2) reduction, urea electrochemical synthesis, CO_(2) hydrogenation, and Ch4 activation. Then the concept of rational design of SACs for precisely controlling reaction pathways is discussed from the aspects of pore structure design, support-metal strong interaction, and support hydrophilic/hydrophobic. Finally, we summarize the challenges encountered by SACs in the field of precise catalytic processes and outline prospects for their further development in this domain.

关键词： single atom catalysts selective oxidation CO2RR bond coupling

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Mechanism of acupuncture in attenuating cerebral ischaemia-reperfusion injury based on nuclear receptor coactivator 4 mediated ferritinophagy

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Journal of Traditional Chinese Medicine 2024年第2期44卷 345-352页

作者： zhANG Xinchang huang zheng huang Peiyan YANG Mengning zhANG zhihui NI Guangxia College of Acupuncture-Moxibustion and Tuina Nanjing University of Chinese MedicineNanjing 210023China Key Laboratory of Acupuncture and Medicine Research of Ministry of Education Nanjing University of Chinese MedicineNanjing 210023China

OBJECTIVE:To explore the effect of acupuncture treatment on cerebral ischaemia-reperfusion injury(CIRI)and reveal the underlying mechanism of the effect based on nuclear receptor coactivator 4(NCOA4)mediated ***:Sprague-Dawley male rats were divided into four groups:the sham group,model group,acupuncture group,and sham acupuncture *** 2 h of middle cerebral artery occlusion(MCAO),reperfusion was performed for 24 h to induce *** rats were treated with acupuncture at the Neiguan(PC6)and Shuigou(GV26)*** neurological function was evaluated by taking their Bederson scores at 2 h after ischaemia and 24 h after *** chloride staining was applied to assess the cerebral infarct volume at 24 h after *** malondialdehyde(MDA)and ferrous iron(Fe^(2+))levels were observed after 24 h of reperfusion using an assay *** blotting was performed to detect the expression of NCOA4 and ferritin heavy chain 1(FTh1)at 24 h after ***,the colocalization of ferritin with neurons,NCOA4 with microtubule-associated protein 1 light chain 3(LC3),and NCOA4 with ferritin was visualized using immunofluorescence ***:Acupuncture significantly improved neurological function and decreased cerebral infarct volume in the acupuncture *** CIRI,the expression of NCOA4,LC3 and FTh1 was increased,which enhanced ferritinophagy and induced an inappropriate accumulation of Fe^(2+)and MDA in the ischaemic ***,acupuncture dramatically downregulated the expression of NCOA4,LC3 and FTh1,inhibited the overactivation of ferritinophagy,and decreased the levels of MDA and Fe^(2+).CONCLUSIONS:Acupuncture can inhibit NCOA4-mediated ferritinophagy and protect neurons against CIRI in a rat model.

关键词： acupuncture ferritinophagy ferroptosis ferritin nuclear receptor coactivator 4 cerebral ischaemia-reperfusion injury

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Laminar Flame Structure-Dependent Exergy Destruction Behavior at Auto-Ignition Time Scale:A Case Study of Dimethyl Ether(DME)

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Journal of Thermal Science 2024年第4期33卷 1257-1271页

作者： WU honghuan huang Wenlin zhAO hao SUN Wuchuan huang zuohua zhANG Yingjia State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an710049China

hybrid deflagration/auto-ignition flame structures coexist in the combustion of advanced *** exergy destruction caused by different irreversible processes under varied flame regimes is thus important for understanding engine *** this study,the flame propagation modes for the premixed DME/air mixtures are numerically investigated under engine-relevant *** entropy generation and exergy destruction characteristics are compared under different flame *** reveal that as the typical premixed flame transition towards auto-ignition front,the exergy destruction from heat conduction and species mass diffusion gradually vanish and are dominated by chemical *** distributions of temperature and species mole fraction in the flame domain are analyzed to clarify the exergy destruction behaviors caused by heat conduction and mass ***,by dividing the DME oxidation process into four stages,the main reaction channels that contribute to the increase in exergy destruction from chemical reaction have been *** is found that the production and consumption of Ch_(2)O and hO_(2) radical dominate the exergy destruction behavior during DME *** this basis,the kinetic mechanism of low-temperature chemistry causing greater exergy destruction is ***,low-temperature chemistry leads to significant exergy destruction due to(a)the large irreversibility of itself and(b)(mainly)the enhancement of h_(2)O_(2)loop reactions by low-temperature reaction *** the reduction of combustion irreversibility is promising to be achieved by reasonably regulating the fuel oxidation path.

关键词： exergy destruction flame structures entropy generation low-temperature chemistry DME

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Chimeric Monkey Born Alive with a high Contribution of Donor Cells

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Neuroscience Bulletin 2024年第6期40卷 849-851页

作者： Jia huang Jun Wu Department of Molecular Biology University of Texas Southwestern Medical CenterDallasTX75390USA hamon Center for Regenerative Science and Medicine University of Texas Southwestern Medical CenterDallasTX75390USA Cecil h.and Ida Green Center for Reproductive Biology Sciences University of Texas Southwestern Medical CenterDallasTX75390USA

Chimeras,which consist of cells from different individuals or different species,represent an important tool in biological *** in the early twentieth century,studies on chimeras have been focusing on understanding fundamental genetic and cellular developmental *** the advances in genetic engineering and embryonic stem cell(ESC)technology,chimeras have become an important tool for the generation of transgenic animals.

关键词： mechanisms. advances developmental

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