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Journal of Road engineering 2024年第2期4卷 224-233页

作者： Ikenna d.Uwanuakwa Ilham Yahya Amir Lyce Ndolo Umba department of Civil engineering Near East UniversityMersin 10Turkey Faculty of Sciences University of LubumbashiLubumbashiThe Democratic Republic of Congo

This study introduces and evaluates a novel artificial hummingbird algorithm-optimised boosted tree(AHAboosted)model for predicting the.d.namic modulus(e*)of hot mix asphalt *** a substantial dataset from NCHRP Report-547,the model was trained and rigorously *** metrics,specifically RMSe,MAe,and R2,were employed to assess the model's predictive accuracy,robustness,and *** benchmarked against well-established models like support vector machines(SVM)and gaussian process regression(GPR),the AHA-boosted model demonstrated enhanced *** achieved R2 values of 0.997 in training and 0.974 in testing,using the traditional Witczak NCHRP 1-40d model *** features such as test temperature,frequency,and asphalt content led to a 1.23%increase in the test R2,signifying an improvement in the model's *** study also explored feature importance and sensitivity through SHAP and permutation importance plots,highlighting binder complex modulus|G*|as a key *** the AHA-boosted model shows promise,a slight decrease in R2 from training to testing indicates a ne.d.for further ***,this study confirms the AHA-boosted model as a highly accurate and robust tool for predicting the.d.namic modulus of hot mix asphalt concrete,making it a valuable asset for pavement engineering.

关键词： Asphalt dynamic modulus Prediction Artificial hummingbird algorithm Boosted tree

Ultrafast magneto-optical dynamics in nickel(111)single crystal studied by the integration of ultrafast reflectivity and polarimetry probes

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Chinese Physics B 2024年第3期33卷 65-69页

作者：匡皓余军潇陈洁 H.e.elsayed-Ali 李润泽 Peter M.Rentzepis School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Center for Transformative Science ShanghaiTech UniversityShanghai 201210China Center for Ultrafast Science and Technology Key Laboratory for Laser Plasmas (Ministry of Education)Collaborative Innovation Center of IFSA (CICIFSA)School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China department of electrical and Computer engineering Old Dominion UniversityNorfolkVirginia 23529USA department of electrical and Computer engineering Texas A&M UniversityCollege StationTexas 77843USA

With the integration of ultrafast reflectivity and polarimetry probes,we observed carrier relaxation and spin dynamics induced by ultrafast laser excitation of Ni(111)single *** carrier relaxation time within the linear excitation range reveals that electron-phonon coupling and dissipation of photon energy into the bulk of the crystal take tens of *** the other hand,the observed spin dynamics indicate a longer time of about 120 *** further understand how the lattice.d.gree of fre.d.m is coupled with these.d.namics may require the integration of an ultrafast diffraction probe.

关键词： ultrafast spin dynamics non-equilibrium dynamics multi-probe

Non-spectator Contributions to Lifetime of ∧b

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Communications in Theoretical Physics 2004年第5X期42卷 723-734页

作者： CHANGChao-hsi GUOPeng LIXue-Qian WANGGuo-Li InstituteofTheoreticalPhysics AcademiaSinicaP.O.Box2735Beijing100080China departmentofPhysics NankaiUniversityTianjin300071China

In this work, we study the contributions of non-spectator effects to the lifetimes of Λb and B-mesons comparatively. Based on the well-established theoretical framework about the effective weak Lagrangian, we.d.rive the formulation of the non-spectator effects at the quark level. especially, for Λb we have considered two pictures: the three-valence-quark picture and the quark-diquark picture. In the two pictures, the interference contributions to the total width are.d.fferent, in this work, we investigate the interference effects in detail. As a preliminary estimate on the lifetimes, we evaluate the hadronic matrix elements appearing in the final formulas of the lifetimes by means of a simple phenomenological model for both pictures. Our results show that the contributions of the non-spectator effects can reduce the ratio of lifetime of Λb to that of B-mesons by 5 ～ 7%. It is noted that in the quark-diquark picture the ratio can be further reduced if excited states of the.d.quark system are taken into account. We conclude that the measured ratio τ(Λb)/τ(B0)(≈)0.79 [The.d.ta Group, Phys. Rev. d66 (2002) 010001] can be partly understood by the non-spectator effects, although the problem on the.d.screpancy between theoretical prediction and experimental measurement is not fully solved.

关键词：寿命粒子物理学重夸克效应衰退轨道

Advances in ground heat exchangers for space heating and cooling:Review and perspectives

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energy and Built environment 2024年第2期5卷 255-269页

作者： Ping Cui Weibo Yang Wenke Zhang Ke Zhu Jeffrey d.Spitler Mingzhi Yu School of Thermal engineering Shandong Jianzhu UniversityJinanShandong 250101China College of electrical Energy and Power EngineeringYangzhou UniversityYangzhouJiangsu 225127China department of Mechanical engineering Oklahoma State UniversityStillwaterOKUSA

As a renewable energy source,geothermal energy has been widely used to provide space heating and cooling for *** thermal performance of ground heat exchanger(GHe)is significant for the operating efficiency of the ground source heat pump(GSHP)*** paper presents a comprehensive review of developments and advances of three kinds of GHe,including vertical borehole GHe(VBGHe),Pile GHe(PGHe),and deep borehole GHe.d.GHe)which are currently popular in larger GSHP ***,analytical models proposed to ana-lyze heat transfer process of VBGHe with different geological conditions are summarized,such as homogenous or heterogeneous ground,with or without groundwater *** and short-time step models and measures to improve GHe thermal performance are also ***,a summary of research advances in PGHe is provided,which includes the heat transfer models of PGHe,the effects of geometric structure,oper-ation modes,pile spacing,use of phase change material(PCM),thermal properties of PCM,thermo-mechanical behavior and/or thermal performance of *** effects of groundwater flow direction and velocity on PGHe are also summarized in ***,models of three kinds of dBGHes,i.e.,deep coaxial GHe.d.GHe),deep U-be.d.GHe.d.GHe)and super-long gravity heat pipe(SLGHP),are *** physical bases of the.d.f-ferent analytical models are elaborated and also their advantages and disadvantages are *** in numerical modelling and improving numerical model calculation spe.d.of dCBHe.d.BHe array,and dUBHe are *** review provides a meaningful reference for the further study of GHes.

关键词： Vertical borehole ground heat exchanger Pile ground heat exchanger deep borehole ground heat exchanger Modelling

Study of the Bc—Meson Lifetime

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Communications in Theoretical Physics 2001年第1期35卷 57-60页

作者： CHANGChao－hsi CHeNShao－Long 等 CCAST（WorldLabortory） P.O.Box8730Beijing100080China InstituteofTheoreticalPhysics theChineseAcademyofSciencesBeijing100080China departmentofPhysics NankaiUniversityTianjin300

We in terms of optical theorem estimate the lifetime of Bc meson with the parameters which are.d.termined by fitting the.d.ta for the lifetimes and inclusive semileptonic decays of various B and d mesons. In the estimation, we find that the bound-state effects are important, and take them into account carefully in the framework which attributes the effects to the effective masses of the.d.cay heavy quarks in the inclusive processes. We also find that to Bc lifetime the penguin contribution is enhanced due to possible interference between the penguin and the 'tree part' c1O1 + c2O2.

关键词： B-c meson lifetime

exploring one material for dual applications:A red-emitting Mg2GeO4:eu3+ nanophosphor for future generation energy efficient WLeds and dosimetric applications

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Journal of Rare earths 2024年第10期42卷 1835-1845页

作者： Akshay Arjun G.P.darshan S.C.Sharma H.Nagabhushana d.V.Sunitha H.B.Premkumar department of Physics Faculty of Mathematical and Physical SciencesM.S.Ramaiah University of Applied Sciences Jain University C.N.R.Rao Centre for Advanced Materials Tumkur University School of Applied Sciences (Physics) REVA University

The envisaged design and developme nt of individual mate rials to excavate a broader spectrum of desired properties and offer multiple applications are highly *** this in mind,a series of forsterite-structured Mg2GeO4:eu3+（1 mol%-9 mol%） nanophosphors was synthesized via a solution combustion method using oxalyl dihydrazide as a *** X-ray diffraction patterns confirm the orthorhombic crystal system with a Puma space *** results clearly show irregularly shaped cluster-like structures with aggregation of the *** diffuse reflectance spectra,the optical energy band gap of the Mg2GeO4:eu3+（1 mol%-9 mol%） nanophosphors was estimated and obtained to be～4.12-4.32 *** photoluminescence emission spectra exhibit intense peaks at ～579,589,610,661,and 707 nm,which are.d.e to characteristic5d0→7F0,5d0→7F1,5do→7F2,5d0→7F3and5d0→7F4transitions of eu3+ions,*** Commission International de L'eclairage color coordinates are gradually tuned from pale red（0.5980,0.4012） to a pure red（0.6385,0.3611） *** glow peaks showcase excellent super-linear response at low doses of γ-irradiations,indicating that the prepared phosphor can be used in thermoluminescent personal dosimetry which is a biological tissue *** aforementioned results demonstrate that the prepared Mg2GeO4:eu3+（1 mol%-9 mol%） nanophosphors are considered an excellent candidate for dual applications,i.e.,red component in future generation white-light-emitting diodes（WLeds） and personal dosimetric applications.

关键词： dosimetry Nanophosphors Photoluminescence Photometric properties Rare earths Thermoluminescence

effect of biochar on the metabolome of soybean se.d.ings

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Oil Crop Science 2024年第1期9卷 60-68页

作者： Nathalia e.Silva Mariana G.Aguilar Osania e.Ferreira Gleicia M.Paulino Jaqueline C.L.Carvalho Lúcia P.S.Pimenta Alan R.T.Machado Programa de Pos-graduaçao em Ciencias Ambientais Universidade do Estado de Minas GeraisFrutalMinas Gerais38202-436Brazil departamento de Química Universidade Federal de Minas GeraisMinas GeraisBelo Horizonte31270-901Brazil departamento de engenharia Aplicada e Tecnologias Ambientais Universidade do Estado de Minas GeraisJoao MonlevadeMinas Gerais35930-314Brazil departamento de Ciencias exatas Universidade do Estado de Minas GeraisJoao MonlevadeMinas Gerais35930-314Brazil

The use of biochar can have several effects on plant germination,depe.d.ng on raw material,preparation method and application ***,the molecular mechanisms that le.d.to those results have yet to be *** aim of this research was to improve the understanding of these mechanisms by characterizing the metabolic effects of sugarcane bagasse biochar on soybean *** types of biochars were prepared by pyrolysis at 300℃(SCB300),400℃(SCB400)and 600℃(SCB600).Then,each one was mixed into sand at 1%,3%,5%(w/w)dose,*** experiment was performed in 8 days of incubation,when the number of germinated se.d. and the average radicle length were *** evaluate the metabolome,the.d.y biomass(dB)was subjected to extraction with a mixture of methanol-d4 and d2O(1:1 v/v).The extracts were submitted to metabolomics analysis by Proton Nuclear Magnetic *** Relative Germination,Relative Average Radicle Growth and Germination Index increased in all treatments compared to *** the other hand,the.d. increased in all treatments,except for SCB300,at doses of 1%and 3%w/*** metabolites(alanine,asparagine,acetic acid,citric acid,glycerol,fatty acids and sucrose)were identified and quantified in dB extracts as the most influential finding for the separation of *** together,these results strongly suggested that biochars accelerated the catabolism of triacylglycerols to sucrose and induced a slight osmotic stress.

关键词： Germination Metabolomics 1H NMR Pyrolysis Sugarcane bagasse

Insight into vertical piezoelectric characteristics regulated thermal transport in van der Waals two-dimensional materials

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Rare Metals 2024年第2期43卷 770-779页

作者： dong-Hai Wei e Zhou Jin-Yuan Xu Hui-Min Wang Chen Shen Hong-Bin Zhang Zhen-Zhen Qin Guang-Zhao Qin State Key Laboratory of Advanced design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha410082China Hunan Key Laboratory for Micro-Nano energy Materials and device and School of Physics and Optoelectronics Xiangtan UniversityXiangtan411105China Institute of Materials Science Technical University of DarmstadtAlarich-Weiss-Str.264287DarmstadtGermany School of Physics and Microelectronics Zhengzhou UniversityZhengzhou450001China

The urgent demand of extreme(ultra-high/low)thermal conductivity materials is triggered by the high-power device,where exploring the theories and mechanisms of regulating thermal transport properties plays a key ***,we elaborately investigate the effect of vertical(out-of-plane)piezoelectric characteristics on thermal transport,which is historically *** different stacking-order(AA and AB)bilayer boron nitride(Bi-BN)in two-dimensional(2d)materials are selected as study *** performing state-of-the-art first-principles calculations,it is found that the polarization charge along the out-of-plane orientation asce.d. significantly with the increasing piezoelectric response in AB stacked Bi-BN(Bi-BN-AB)followed by the enhanced interlayer B–N atomic ***,the amplitude of phonon anharmonicity in Bi-BN-AB increases larger than that in the AA stacked Bi-BN(Bi-BN-AA),resulting in the.d.amatic weakening of the thermal conductivity by 20.34%under 18%*** research reveals the significant role of the vertical(out-of-plane)piezoelectric characteristic in regulating thermal transport and provides new insight into accurately exploring the thermal transport performance of 2d van der Waals materials.

关键词： Thermal conductivity Piezoelectric effect 2d materials Bilayer BN Strain engineering

Instantaneous Bethe-Salpeter equation and Its exact Solution

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Communications in Theoretical Physics 2005年第1期43卷 113-118页

作者： CHANGChao-hsi CHeNJiao-Kai LIXue-Qia WANGGuo-Li CCAST（WorldLaboratory） P.O.Box8730Beijing100080China／／InstituteofTheoreticalPhysicstheChineseAcademyofSciencesP.O.Box2735Beijing100080China InstituteofTheoreticalPhysics theChineseAcademyofSciencesP.O.Box2735Beijing100080China／／GraduateSchooloftheChineseAcademyofSciencesBeijing100039China CCAST（WorldLaboratory） P.O.Box8730Beijing100080China／／DepartmentofPhysicsNankaiUniversityTianjin300071China departmentofPhysics NankaiUniversityTianjin300071China／／DepartmentofPhysicsFujianNormalUniversityFuzhou350007China

We present an approach to solve Bethe-Salpeter (BS) equations exactly withoutany approximation if the kernel of the BS equations exactly is instantaneous, and take positroniumas an example to illustrate the general features of the exact solutions. The key step for theapproach is from the BS equations to derive a set of coupled and well-determined integrationequations in linear eigenvalue for the components of the BS wave functions equivalently, which maybe solvable numerically under a controlled accuracy, even though there is no analytic solution. Forpositronium, the exact solutions precisely present corrections to those of the correspondingSchrodinger equation in order υ~1 (υ is the relative velocity) for eigenfunctions, in order υ~2for eigenvalues, and the mixing between S and d components in J~(PC) = 1~(--) states etc.,quantitatively. Moreover, we also point out that there is a questionable step in some existentderivations for the instantaneous BS equations if one is pursuing the exact solutions. Finally, weemphasize that one should take the O(υ) corrections emerging in the exact solutions into accountaccordingly if one is interested in the relativistic corrections for relevant problems to the boundstates.

关键词： instantaneous BS equation exact solutions positronium relativisticcorrections

Photosynthetic response to a winter heatwave in le.d.ng and trailing edge populations of the intertidal red alga Corallina offi-cinalis(Rhodophyta)

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Acta Oceanologica Sinica 2024年第7期43卷 70-77页

作者： Regina Kolzenburg Federica Ragazzola Laura Tamburello Katy R.Nicastro Christopher d.McQuaid Gerardo I.Zardi UmeåMarine Sciences Centre UmeåUniversity90571 NorrbynSweden University of Portsmouth Institute of Marine SciencePortsmouth PO49LYUK Stazione Zoologica Anton dohrn Genova Marine CenterGenova 16126Italy Stazione Zoologica Anton dohrn Sicily Marine CenterPalermo 90149Italy department of Zoology and entomology Rhodes UniversityMakhanda(Grahamstown)6139South Africa Centre of Marine Sciences University of AlgarveFaro 8005-139Portugal Laboratoire.d.Océanologie et de Géosciences Universitéde LilleLille 59000France Universitéde Caen Normandie Laboratoire de Biologie des Organismes et des Ecosystèmes AquatiquesCaen 14032France

Marine heatwaves(MHWs)caused by anthropogenic climate change are becoming a key driver of change at the ecosystem *** conditions experienced by marine organisms across their distribution,particularly towards the equator,are likely to approach their physiological limits,resulting in extensive mortality and subsequent changes at the population *** at the margins of their species’distribution are thought to be more sensitive to climate-induced environmental pressures than central populations,but our understanding of variability in fitness-related physiological traits in trailing versus le.d.ng-edge populations is *** a laboratory simulation study,we tested whether two le.d.ng(Iceland)and two trailing(Spain)peripheral populations of the intertidal macroalga Corallina officinalis display different levels of maximum potential quantum efficiency(Fv/Fm)resilience to current and future winter MHWs *** study revealed that ongoing and future local winter MHWs will not negatively affect le.d.ng-edge populations of ***,which exhibited stable photosynthetic efficiency throughout the *** edge populations showed a positive though non-significant tre.d.in photosynthetic efficiency throughout winter MHWs *** and equatorward populations did not produce significantly different results,with winter MHWs having no negative affect on Fv/Fm of either ***,we found no long-term regional or population-level influence of a winter MHWs on this species’photosynthetic ***,we found no statistically significant difference in thermal stress responses between le.d.ng and trailing ***,*** showed a tre.d.towards higher stress responses in southern than northern *** responses rest on a variety of local population traits,they are.d.fficult to predict based solely on thermal pressures.

关键词： marginal population coralline algae climate change ecophysiology photophysiology macroalgae Fv/Fm