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Compressive property and energy absorption characteristic of interconnected porous Mg-Zn-Y alloys with adjusting Y addition

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Journal of Magnesium and Alloys 2024年第1期12卷 171-185页

作者： J.A.Liu S.J.Liu b.wang w.b.Sun X.J.Liu Z.w.Han College of Materials Science and Engineering Key Laboratory of Automobile Materials(Ministry of Education)Jilin UniversityChangchun 130022PR China Key Laboratory of bionic Engineering(Ministry of Education) College of Biological and Agricultural EngineeringJilin UniversityChangchun130022PR China weihai Institute for bionics-Jilin University Weihai 264205PR China

In this study,interconnected porous Mg-2Zn-xY alloys with different phase compositions were prepared by various Y additions(x=0.4,3,and 6 wt.%)to adjust the compressive properties and energy absorption *** characterization methods were then applied to identify the microstructure of the porous Mg-Zn-Y and describe the details of the second *** tests were performed at room temperature(RT),200℃,and 300℃to study the impact of the Y addition and testing temperature on the compressive properties of the porous *** experimental results showed that a high Y content promotes a microstructure refinement and increases the volume fraction of the second *** the Y content increases,different Mg-Zn-Y ternary phases appear:I-phase(Mg_(3)Zn_(6)Y),w-phase(Mg_(3)Zn_(3)Y_(2)),and LPSO phase(Mg_(12)ZnY).when the Y content ranges between 0.4%and 6%,the compressive strength increases from 6.30MPa to 9.23 MPa,and the energy absorption capacity increases from 7.33 MJ/m^(3)to 10.97 MJ/m^(3)at RT,which is mainly attributed to the phase composition and volume fraction of the second ***,the average energy absorption efficiency is independent of the Y *** addition,the compressive deformation behaviors of the porous Mg-Zn-Y are altered by the testing *** compressive strength and energy absorption capacity of the porous Mg-Zn-Y decrease due to the softening effect of the high temperature on the *** deformation behaviors at different temperatures are finally observed to reflect the failure mechanisms of the struts.

关键词： Porous magnesium Rare earth elements Microstructure Compressive behavior Energy absorption characteristic

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Probing the bardeen-Kiselev black hole with the cosmological constant caused by Einstein equations coupled with nonlinear electrodynamics using quasinormal modes and greybody bounds

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Communications in Theoretical Physics 2024年第6期76卷 102-119页

作者： S R wu b Q wang Z w Long College of Physics Guizhou UniversityGuiyang 550025China College Pharmacy Guizhou University of Traditional Chinese MedicineGuiyang 550025China

In this work,we investigate a static and spherically symmetric bardeen-Kiselev black hole(bH)with the cosmological constant,which is a solution of the Einstein-non-linear Maxwell field *** compute the quasinormal frequencies for the bardeen-Kiselev bH with the cosmological constant due to electromagnetic and gravitational *** varying the bH parameters,we discuss the behavior of both real and imaginary parts of the bH quasinormal frequencies and compare these frequencies with the Reissner-Nordström-de Sitter bH surrounded by quintessence(RN-dSQ).Interestingly,it is shown that the responses of the bardeen-Kiselev bH with the cosmological constant and the RN-dSQ under electromagnetic perturbations are different when the charge parameter q,the state parameter w and the normalization factor c are varied;however,for the gravitational perturbations,the responses of the bardeen-Kiselev bH with the cosmological constant and the RN-dSQ are different only when the charge parameter q is ***,compared with the gravitational perturbations,the electromagnetic perturbations can be used to understand nonlinear and linear electromagnetic fields in curved spacetime *** interesting observation is that,due to the presence of Kiselev quintessence,the electromagnetic perturbations around the bardeen-Kiselev bH with the cosmological constant damps faster and oscillates slowly;for the gravitational perturbations,the quasinormal mode decays slowly and oscillates *** also study the reflection and transmission coefficients along with the absorption cross section in the bardeen-Kiselev bH with the cosmological constant;it is shown that the transmission coefficients will increase due to the presence of Kiselev quintessence.

关键词： quasinormal modes greybody factors bardeen-Kiselev black hole with cosmological constant

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Superexchange and charge transfer in the nickelate superconductor La_(3)Ni_(2)O_(7) under pressure

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Science China(Physics,Mechanics & Astronomy) 2024年第11期67卷 1-8页

作者： wéi wú Zhihui Luo Dao-Xin Yao Meng wang Center for Neutron Science and Technology Guangdong Provincial Key Laboratory of Magnetoelectric Physics and DevicesSchool of PhysicsSun Yat-sen UniversityGuangzhou 510275China

Recently, a bulk nickelate superconductor La_(3)Ni_(2)O_(7) is discovered at pressures with a remarkable high transition temperature T_(c)~ 80 K. Here, we study a Hubbard model with tight-binding parameters derived from ab initio calculations of La_(3)Ni_(2)O_(7),by employing large scale determinant quantum Monte Carlo and cellular dynamical mean-field theory. Our result suggests that the superexchange couplings in this system are comparable to that of cuprates. The system is a charge transfer insulator as the hole concentration becomes four per site at large Hubbard U. Upon hole doping, two low-energy spin-singlet bands emerge in the system exhibiting distinct correlation properties: while the one composed of the out-of-plane Ni-d_(3z^(2)-r^(2)) and O-p_(z) orbitals demonstrates strong antiferromagnetic correlations and narrow effective bandwidth, the in-plane singlet band consisting of the Ni-d_(x^(2)-y^(2)) and O-p_(x)/p_(y) orbitals is in general more itinerant. Over a broad range of hole doping, the doped holes occupy primarily the d_(x^(2)-y^(2)) and p_(x)/p_(y) orbitals, whereas the d_(3z^(2)-r^(2)) and p_(z) orbitals retain underdoped. we propose an effective t-J model to capture the relevant physics and discuss the implications of our result for comprehending the La_(3)Ni_(2)O_(7) superconductivity.

关键词： superconductivity nickelate superconductors Hubbard model superexchange charge transfer insulator quantum Monte Carlo

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The impact of the Rural Minimum Living Standard Guarantee(Rural Dibao)Program on child nutrition outcomes

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Journal of Integrative Agriculture 2024年第2期23卷 444-456页

作者： Dian Chen Xiangming Fang Yu Chen Xiaodong Zheng Zhuo Chen Rodney b.w.Smith Academy of Global Food Economics and Policy China Agricultural UniversityBeijing 100083China School of Public Health Georgia State UniversityAtlanta 30303USA School of Economics Zhejiang Gongshang UniversityHangzhou 310018China College of Public Health University of GeorgiaAthens 30602USA Department of Applied Economics University of MinnesotaSaint Paul 55108USA

The Rural Minimum Living Standard Guarantee(Rural Dibao)is an important unconditional cash transfer program to alleviate poverty in rural *** the importance of children’s nutrition in breaking poverty cycles,little is known about the impact of Rural Dibao on child nutrition *** China Family Panel Studies(CFPS),this paper examines the effects of Rural Dibao on child nutrition outcomes and investigates potential pathways and heterogeneous *** exploit propensity score matching and difference-in-differences techniques to evaluate the effects of the Rural Dibao program on child nutrition *** results suggest that Rural Dibao significantly impacts the nutrition outcomes of children up to 15 years of ***,our results suggest that Rural Dibao improves child height-to-age z-scores by 1.05 standard deviations and lowers the probability of stunting by 11.9 percentage *** analyses suggest that increased protein intake is the main pathway through which Rural Dibao participation contributes to better nutrition *** also find that the effect of the program is more pronounced among girls,children who are non-left-behind or live with highly educated mothers,and those from low-income families and poor *** findings suggest that Rural Dibao participation helps improve child nutrition outcomes through improving diet quality.

关键词： Rural Minimum Living Standard Guarantee nutrition height-to-age z-scores stunting rural China

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Inflow and outflow permeability tests in a very soft clay under low stresses

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3270-3283页

作者： J.w.S.Vargas F.A.b.Danziger F.R.Lopes T.Lunne Federal University of Rio de Janeiro Rio de JaneiroBrazil Norwegian Geotechnical Institute OsloNorway

In situ inflow and outflow permeability tests with the bAT probe at SarapuíII soft clay test site are presented.A description of the bAT permeability test is provided,discussing its advantages and shortcomings,especially in the case of very soft clays under low *** pressures were monitored during probe installation and were found to be slightly lower than piezocone u2 pore pressures,consistent with the position of the *** role of filter tip saturation was investigated after the usual saturation procedure provided an unsatisfactory pore pressure response during probe *** show that the vacuum saturation procedure provides adequate response during installation and increases the reliability of the coefficient of permeability determination in early *** inflow and outflow tests yielded similar results,indicating that careful execution of the test can lead to good test repeatability regardless of the loading *** sequences of alternated inflow and outflow tests have yielded similar results,indicating that soil reconsolidation and filter clogging were negligible in the tests *** are presented concerning the relationship between index parameters and the in situ coefficient of permeability for SarapuíII clay,which plot outside the range of existing databases.

关键词： Permeability test Soft clay bAT probe Inflow and outflow tests

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Rescattering of stimulated Raman side scattering in nonuniform plasmas

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Matter and Radiation at Extremes 2024年第5期9卷 68-76页

作者： S.Tan Q.wang Y.Chen w.b.Yao C.Z.Xiao J.F.Myatt School of Physics and Electronics Hunan UniversityChangsha 410082China Institute of Applied Physics and Computational Mathematics Beijing 100094China School of Electrical and Information Engineering Anhui University of Science and TechnologyHuainanAnhui 232001China Department of Electrical and Computer Engineering University of Alberta9211116 St.NWEdmontonAlberta T6G 1H9Canada

Rescattering of stimulated Raman side scattering(SRSS)is observed for the first time via two-dimensional(2D)particle-in-cell(PIC)*** construct a theoretical model for the rescattering process,which can predict the region of occurrence of mth-order SRSS and estimate its *** rescattering process is identified by the 2D PIC simulations under typical conditions of a direct-drive inertial confinement fusion *** electrons produced by second-order SRSS propagate nearly perpendicular to the density gradient and gain nearly the same energy as in first-order SRSS,but there is no cascade acceleration to produce superhot *** studies for a wide range of ignition conditions show that SRSS and associated rescatterings are robust and important processes in inertial confinement fusion.

关键词： nonuniform acceleration scattering

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Tumor necrosis factor-alpha, transforming growth factor-beta, degree of lower urinary tract symptoms as predictors of erectile dysfunction in benign prostatic hyperplasia patients

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Asian Journal of Urology 2024年第2期11卷 280-285页

作者： Gede w.K.Duarsa Yeremia G.Kusumah Ronald Sugianto Pande M.w.Tirtayasa Tjokorda G.b.Mahadewa Department of Urology Faculty of MedicineUniversitas UdayanaProf.Dr.I.G.N.G Ngoerah General HospitalBaliIndonesia Department of General Surgery Faculty of MedicineUniversitas UdayanaProf.Dr.I.G.N.G Ngoerah General HospitalBaliIndonesia Medical Doctor Study Program Faculty of MedicineUniversitas UdayanaBaliIndonesia Department of Urology Faculty of MedicineUniversitas UdayanaUniversitas Udayana Teaching HospitalBaliIndonesia Department of Neurosurgery Faculty of MedicineUniversitas UdayanaProf.Dr.I.G.N.G Ngoerah General HospitalBaliIndonesia

Objective: Erectile dysfunction (ED) is a condition of insufficient penile erection, consistently or recurrently, for sexual activity. Tumor necrosis factor-alpha (TNF-α) induces transforming growth factor-beta (TGF-β), which causes the transition of epithelial cells into mesenchymal cells that affect ED. This study aimed to evaluate the roles of TNF-α, TGF-β, degree of lower urinary tract symptoms, and prostatic volume for the presence of ED in benign prostatic hyperplasia (bPH) ***: Our study performed an analytic observational retrospective cohort study using secondary data from four hospitals in bali, Indonesia, including medical records and other administrative data. The sample was bPH patients with several history ***: Our sample was 83 respondents, ranging from 50 years to 80 years, 61 respondents with ED and 22 with non-ED. The International Prostate Symptom Score showed a significant result, which indicates that ED is more common in patients with higher International Prostate Symptom Score (p=0.002). Moreover, the TNF-α of ≥43.9 pg/mg and TGF-β of ≥175.8 pg/mL were significantly associated with the presence of ED in bPH patients (pwith ED (p=0.947).Conclusion: TNF-α, TGF-β, and lower urinary tract symptoms severity can predict the occurrence of ED in bPH, while prostatic volume was not significant.

关键词： Prostate enlargement biomarker Erectiledysfunction Riskfactor

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Spatiotemporal dynamics in butterfly hybrid zones

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Insect Science 2024年第2期31卷 328-353页

作者： Ananda R.Pereira Martins Natalie b.warren w.Owen McMillan Rowan D.H.barrett Redpath Museum McGill University859 Sherbrooke Street WestMontrealQuebecCanada Smithsonian Tropical ResearchInstitute GamboaPanama CityPanama

Evaluating whether hybrid zones are stable or mobile can provide novelinsights for evolution and conservation biology. butterflies exhibit high sensitivity to envi-ronmental changes and represent an important model system for the study of hybrid zoneorigins and maintenance. Here, we review the literature exploring butterfly hybrid zones,with a special focus on their spatiotemporal dynamics and the potential mechanisms thatcould lead to their movement or stability. we then compare different lines of evidenceused to investigate hybrid zone dynamics and discuss the strengths and weaknesses ofeach approach. Our goal with this review is to reveal general conditions associated withthe stability or mobility of butterfly hybrid zones by synthesizing evidence obtained us-ing different types of data sampled across multiple regions and spatial scales. Finally, wediscuss spatiotemporal dynamics in the context of a speciation/divergence continuum, therelevance of hybrid zones for conservation biology, and recommend key topics for futureinvestigation.

关键词： butterflies human impacts hybrid zones movement spatiotemporaldynamics stability

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Generalized time-dependent generator coordinate method for induced fission dynamics

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Frontiers of physics 2024年第4期19卷 1-12页

作者： b.Li D.Vretenar T.Nikšić J.Zhao P.w.Zhao J.Meng State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China Physics Department Faculty of ScienceUniversity of Zagreb10000 ZagrebCroatia Center for Circuits and Systems Peng Cheng LaboratoryShenzhen 518055China

The generalized time-dependent generator coordinate method(TD-GCM)is extended to include pairing *** correlated GCM nuclear wave function is expressed in terms of time-dependent generator states and weight *** particle–hole channel of the effective interaction is determined by a Hamiltonian derived from an energy density functional,while pairing is treated dynamically in the standard bCS approximation with time-dependent pairing tensor and single-particle occupation *** the inclusion of pairing correlations,various time-dependent phenomena in open-shell nuclei can be described more *** model is applied to the description of saddle-to-scission dynamics of induced *** generalized TD-GCM charge yields and total kinetic energy distribution for the fission of 240Pu,are compared to those obtained using the standard time-dependent density functional theory(TD-DFT)approach,and with available data.

关键词： nuclear density functional theory generator coordinate method fission dynamics

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Creep-induced redistribution of alloying elements in CZ1 zirconium alloys

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Journal of Materials Science & Technology 2024年第6期173卷 31-44页

作者： w.T.Lin Q.Y.Lv D.Jiao L.b.Zhang J.Tan G.Sha J.Hu China Nuclear Power Technology Research Institute Shenzhen 518026China School of Material Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China

Introducing minor alloying elements is an effective strategy to improve the corrosion and mechanical properties of zirconium alloys for nuclear *** in-reactor service,external environment and stress can affect the distribution of alloying elements,substantially changing the degradation process of zirconium *** date,there is a lack of in-depth understanding of the interaction between creep and microchemistry ***,we conducted systematic transmission electron microscopy(TEM)and atom probe tomography(APT)investigations to address creep-induced redistribution of alloying elements in CZ1(Zr-Sn-Nb-Fe-Cr-Cu)zirconium alloy with different initial ***,Fe,Sn,and Cu are found to co-segregate at grain *** higher the intermediate annealing temperature,the larger the Gibbsian interfacial excesses of solute elements *** further demonstrate that creep can reduce the excess value of Fe at grain boundaries due to the coarsening of Zr-Fe-Cr second phase particles via grain boundary and dislocation pipe *** the same time,the excess value of Sn is increased by diffusing from the matrix to grain ***,Cu as a minor element in the concentration range of 0.05-0.3 wt.%is found to segregate at dislocations to form the Cottrell atmosphere and develop Cu-rich nanoclusters for suppressing dislocation *** new understanding of the segregation and clustering of minor alloying elements provides guidance for developing zirconium alloys with enhanced creep resistance.

关键词： Zirconium alloy Thermal creep Grain boundary segregation Dislocation segregation Cu-rich nanoclusters

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