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Compressive property and energy absorption characteristic of interconnected porous Mg-Zn-Y alloys w.th 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.w.ng 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 w.ihai Institute for bionics-Jilin University Weihai 264205PR China

In this study,interconnected porous Mg-2Zn-xY alloys w.th different phase compositions w.re prepared by various Y additions(x=0.4,3,and 6 w..%)to adjust the compressive properties and energy absorption *** characterization methods w.re then applied to identify the microstructure of the porous Mg-Zn-Y and describe the details of the second *** tests w.re 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 show.d 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).w.en the Y content ranges betw.en 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,w.ich 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 w.th the cosmological constant caused by Einstein equations coupled w.th 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 w. b Q w.ng Z w.Long College of Physics Guizhou UniversityGuiyang 550025China College Pharmacy Guizhou University of Traditional Chinese MedicineGuiyang 550025China

In this w.rk,w. investigate a static and spherically symmetric bardeen-Kiselev black hole(bH)w.th the cosmological constant,w.ich is a solution of the Einstein-non-linear Maxw.ll field *** compute the quasinormal frequencies for the bardeen-Kiselev bH w.th the cosmological constant due to electromagnetic and gravitational *** varying the bH parameters,w. discuss the behavior of both real and imaginary parts of the bH quasinormal frequencies and compare these frequencies w.th the Reissner-Nordström-de Sitter bH surrounded by quintessence(RN-dSQ).Interestingly,it is show. that the responses of the bardeen-Kiselev bH w.th the cosmological constant and the RN-dSQ under electromagnetic perturbations are different w.en the charge parameter q,the state parameter w.and the normalization factor c are varied;how.ver,for the gravitational perturbations,the responses of the bardeen-Kiselev bH w.th the cosmological constant and the RN-dSQ are different only w.en the charge parameter q is ***,compared w.th 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 w.th the cosmological constant damps faster and oscillates slow.y;for the gravitational perturbations,the quasinormal mode decays slow.y and oscillates *** also study the reflection and transmission coefficients along w.th the absorption cross section in the bardeen-Kiselev bH w.th the cosmological constant;it is show. that the transmission coefficients w.ll increase due to the presence of Kiselev quintessence.

关键词： quasinormal modes greybody factors bardeen-Kiselev black hole w.th cosmological constant

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Gas Exchange Rates of Texas Persimmon (Diospyros texana) in Central Texas w.odlands

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American Journal of Plant Sciences 2024年第5期15卷 329-348页

作者： Matthew.b. Grunstra Oscar w. Van Auken Department of Integrative biology University of Texas at San Antonio San Antonio TX USA

Diospyros texana (Texas persimmon) is a secondary species in most Juniperus ashei/Quercus fusiformis w.odlands in central Texas. It has high density, but plants are mostly in the community understory. Light response curves at ambient and elevated levels of COb>2b> and temperature w.re measured for D. texana. The Ab>netb> (photosynthetic rate) increased significantly as both light level and COb>2b> levels increased but not temperature. The Ab>maxb> (maximum photosynthetic rate) of D. texana in full sun at elevated levels of COb>2b> w.s increased for all treatments. Stomatal conductance increased w.th levels of COb>2b> but only if the interaction w.s removed from the model. Intercellular levels of COb>2b> increased w.th both temperature and COb>2b> treatments as did w.ter use efficiency (w.E). Furthermore, light saturation (Lb>satb>) increased w.th COb>2b> treatments and light compensation (Lb>cpb>) increased w.th temperature. The dark respiration (Rb>db>) increased w.th both temperature and COb>2b> treatments. Markov population models suggested D. texana populations w.uld remain ecologically similar in the future. How.ver, sub-canopy light levels and herbivory should be considered w.en examining population projections. For example, Juniperus ashei juveniles are not recruited into any canopy unless there are high light levels. Herbivory reduces the success of Quercus juveniles from reaching the canopy. These factors do not seem to be a problem for D. texana juveniles w.ich w.uld allow.them to reach the canopy w.thout need of a high light gap and are not prevented by herbivory. Thus, Juniperus/Quercus w.odlands w.ll change in the future to w.odlands w.th D. texana a more common species.

关键词： Replacement Dynamics Ecological Succession CO2 Concentrations Temperature Levels Photosynthetic Rates Drought Tolerance Herbivory Species Replacement Encroachment Juniper

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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 know. 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 pathw.ys 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 low.rs the probability of stunting by 11.9 percentage *** analyses suggest that increased protein intake is the main pathw.y through w.ich Rural Dibao participation contributes to better nutrition *** also find that the effect of the program is more pronounced among girls,children w.o are non-left-behind or live w.th 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 Norw.gian Geotechnical Institute OsloNorway

In situ inflow.and outflow.permeability tests w.th 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 w.re monitored during probe installation and w.re found to be slightly low.r than piezocone u2 pore pressures,consistent w.th the position of the *** role of filter tip saturation w.s 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 w.re negligible in the tests *** are presented concerning the relationship betw.en index parameters and the in situ coefficient of permeability for SarapuíII clay,w.ich plot outside the range of existing databases.

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

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Application of ACP Nonlinear Math in Analyzing Arithmetic and Radiation Transmission Data (Application 1 & 2) [4-21-2024, 820P] (V)

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Journal of Applied Mathematics and Physics 2024年第6期12卷 2302-2319页

作者： Ralph w. Lai Melisa w. Lai-becker Grace Cheng-Dodge 28 Cornerstone Ct. Doylestown PA USA Harvard Medical School Cambridge MA USA Independent Education Consultants West Hartford CT USA

In this study, w. explore the application of ACP (asymptotic curve based and proportionality oriented) Alpha beta (αβ) Nonlinear Math to analyze arithmetic and radiation transmission data. Specifically, w. investigate the relationship betw.en tw. variables. The novel approach involves collecting elementary “y” data and subsequently analyzing the asymptotic cumulative or demulative (opposite of cumulative) Y data. In part I, w. examine the connection betw.en the common linear numbers and ideal nonlinear numbers. In part II, w. delve into the relationship betw.en X-ray energy and the radiation transmission for various thin film materials. The fundamental physical law.asserts that the nonlinear change in continuous variable Y is negatively proportional to the nonlinear change in continuous variable X, expressed mathematically as dα = −Kdβ. Here: dα {Y, Yu, Yb} represents the change in Y, w.th Yu and Yb denoting the upper and baseline asymptote of Y. dβ {X, Xu, Xb} represents the change in X, w.th Xu and Xb denoting the upper and baseline asymptote of X. K represents the proportionality constant or rate constant, w.ich varies based on equation arrangement. K is the key inferential factor for describing physical phenomena.

关键词： Asymptotic Concave and Convex Curve Upper and baseline Asymptote Demulative vs. Cumulative Coefficient of Determination Proportionalityand Position Constant Skew.d bell and Sigmoid Curve

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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.w.ng 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 tw.-dimensional(2D)particle-in-cell(PIC)*** construct a theoretical model for the rescattering process,w.ich 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 w.de 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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Characterization and Modeling of Mechanical Properties of Additively Manufactured Coconut Fiber-Reinforced Polypropylene Composites

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Advances in Materials Physics and Chemistry 2024年第6期14卷 95-112页

作者： George Mosi bernard w. Ikua Samuel K. Kabini James w. Mw.ngi Department of Mechatronic Engineering Jomo Kenyatta University of Agriculture and Technology Juja Kenya

In the face of the increased global campaign to minimize the emission of greenhouse gases and the need for sustainability in manufacturing, there is a great deal of research focusing on environmentally benign and renew.ble materials as a substitute for synthetic and petroleum-based products. Natural fiber-reinforced polymeric composites have recently been proposed as a viable alternative to synthetic materials. The current w.rk investigates the suitability of coconut fiber-reinforced polypropylene as a structural material. The coconut fiber-reinforced polypropylene composites w.re developed. Samples of coconut fiber/polypropylene (PP) composites w.re prepared using Fused Filament Fabrication (FFF). Tests w.re then conducted on the mechanical properties of the composites for different proportions of coconut fibers. The results obtained indicate that the composites loaded w.th 2 w.% exhibited the highest tensile and flexural strength, w.ile the ones loaded w.th 3 w.% had the highest compression strength. The ultimate tensile and flexural strength at 2 w.% w.re determined to be 34.13 MPa and 70.47 MPa respectively. The compression strength at 3 w.% w.s found to be 37.88 MPa. Compared to pure polypropylene, the addition of coconut fibers increased the tensile, flexural, and compression strength of the composite. In the study, an artificial neural netw.rk model w.s proposed to predict the mechanical properties of polymeric composites based on the proportion of fibers. The model w.s found to predict data w.th high accuracy.

关键词： Additive Manufacturing Artificial Neural Netw.rk Mechanical Properties Natural Fibers Polypropylene

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A Preliminary Comparative Study on the Centering Algorithms for CassiniISS NAC Images

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Research in Astronomy and Astrophysics 2024年第10期24卷 58-65页

作者： T.Liang Q.-F.Zhang G.-M.Liu w.-H.Zhu C.-S.w.ng Department of Computer Science Jinan UniversityGuangzhou 510632China Sino-French Joint Laboratory for Astrometry Dynamics and Space ScienceJinan UniversityGuangzhou 510632China School of Computer Science Guangdong University of EducationGuangzhou 510303China

Obtaining high precision is an important consideration for astrometric studies using images from the Narrow.Angle Camera(NAC)of the Cassini Imaging Science Subsystem(ISS).Selecting the best centering algorithm is key to enhancing astrometric *** this study,w. compared the accuracy of five centering algorithms:Gaussian fitting,the modified moments method,and three point-spread function(PSF)fitting methods(effective PSF(ePSF),PSFEx,and extended PSF(x PSF)from the Cassini Imaging Central Laboratory for Operations(CICLOPS)).w. assessed these algorithms using 70 ISS NAC star field images taken w.th CL1 and CL2 filters across different stellar *** ePSF method consistently demonstrated the highest accuracy,achieving precision below.0.03 pixels for stars of magnitude *** to the previously considered best,the modified moments method,the e PSF method improved overall accuracy by about 10%and 21%in the sample and line directions,***,the xPSF model provided by CICLOPS had low.r precision than the ***,the ePSF exhibits an improvement in measurement precision of 23%and 17%in the sample and line directions,respectively,over the *** discrepancy might be attributed to the xPSF focusing on photometry rather than *** findings highlight the necessity of constructing PSF models specifically tailored for astrometric purposes in NAC images and provide guidance for enhancing astrometric measurements using these ISS NAC images.

关键词： methods:analytical techniques:image processing stars:imaging astrometry

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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.w.rren w.Ow.n McMillan Row.n D.H.barrett Redpath Museum McGill University859 Sherbrooke Street WestMontrealQuebecCanada Smithsonian Tropical ResearchInstitute GamboaPanama CityPanama

Evaluating w.ether 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, w. review.the literature exploring butterfly hybrid zones,w.th a special focus on their spatiotemporal dynamics and the potential mechanisms thatcould lead to their movement or stability. w. then compare different lines of evidenceused to investigate hybrid zone dynamics and discuss the strengths and w.aknesses ofeach approach. Our goal w.th this review.is to reveal general conditions associated w.ththe 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, w.discuss 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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