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Generation of polarized electron beams through self-injection in the interaction of a laser with a pre-polarized plasma

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High Power Laser Science and Engineering 2024年第3期12卷 62-68页

作者： L.r.Yin X.F.Li Y.J.Gu N.Cao Q.Kong m.Büscher S.m.Weng m.Chen Z.m.Sheng Key Laboratory of Nuclear Physics and Ion-beam Application(moE) Institute of Modern PhysicsDepartment of Nuclear Science and TechnologyFudan UniversityShanghaiChina State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghaiChina SANKEN(Institute of Scientific and Industrial research) Osaka UniversityOsakaJapan Sichuan research Institute Shanghai Jiao Tong UniversityChengduChina Peter Grünberg Institut(PGI-6) Forschungszentrum JülichJülichGermany Institut für Laser-und Plasmaphysik Heinrich-Heine-Universität DüsseldorfDüsseldorfGermany Key Laboratory for Laser Plasmas(moE) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghaiChina Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghaiChina Tsung-Dao Lee Institute Shanghai Jiao Tong UniversityShanghaiChina

Polarized electron beam production via laser wakefield acceleration in pre-polarized plasma is investigated by particlein-cell *** evolution of the electron beam polarization is studied based on the Thomas±Bargmann±michel±Telegdi equation for the transverse and longitudinal self-injection,and the depolarization process is found to be influenced by the injection *** the case of transverse self-injection,as found typically in the bubble regime,the spin precession of the accelerated electrons is mainly influenced by the ***,in the case of longitudinal injection in the quasi-1D regime(for example,*** et al.,***.110,135002(2013)),the direction of electron spin oscillates in the laser *** the electrons move around the laser axis,the net influence of the laser field is nearly zero and the contribution of the wakefield can be ***,an ultra-short electron beam with polarization of 99%can be obtained using longitudinal self-injection.

关键词： laser wakefield acceleration longitudinal self-injection particle-in-cell simulation polarized electron beam

Freeze-thaw cycles and associated geomorphology in a post-glacial environment:current glacial,paraglacial,periglacial and proglacial scenarios at Pico de Orizaba volcano,mexico

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Journal of mountain Science 2024年第6期21卷 1954-1977页

作者： Víctor SOTO Carlos m.WELSH r. Kenji YOSHIKAWA Hugo DELGADO GrANADOS Centro de Ciencias de la Tierra Universidad VeracruzanaCircuito Gonzalo Aguirre BeltránS/NZona Universitaria91090XalapaMéxico Water and Environmental research Center University of Alaska FairbanksFairbanksAlaska 99775USA Instituto de Geofísica Universidad Nacional Autónoma de MéxicoCiudad de México 04150México Department of Earth and Environmental Sciences Ludwig Maximilians UniversitätMunich 80333Germany

The glacial history of Pico de Orizaba indicates that during the Last Glacial maximum,its icecap covered up to~3000 m asl;due to the air temperature increasing,its main glacier has retreated to 5050 m *** retraction of the glacier has left behind an intense climatic instability that causes a high frequency of freeze-thaw cycles of great intensity;the resulting geomorphological processes are represented by the fragmentation of the bedrock that occupies the upper parts of the *** is a notable lack of studies regarding the fragmentation and erosion occurring in tropical high mountains,and the associated geomorphological risks;for this reason,as a first stage of future continuous research,this study analyzes the freezing and thawing cycles that occur above 4000 m asl,through continuous monitoring of surface ground *** results allow us to identify and characterize four zones:glacial,paraglacial,periglacial and *** was found that the paraglacial zone presents an intense drop of temperature,of up to~9℃ in only sixty *** rock fatigue and intense freeze-thaw cycles that occur in this area are responsible for the high rate of rock disintegration and represent the main factor of the constant slope dynamics that occur at the *** activity decreases,both in frequency and intensity,according to the distance to the glacier,which is where the temperature presents a certain degree of stability,until reaching the proglacial zone,where cycles are almost non-existent,and therefore there is no gelifraction *** geomorphological processes have resulted in significant alterations to the mountain slopes,which can have severe consequences in terms of risk and water.

关键词： Freeze-Thaw Gelifraction mountain mechanical erosion Periglacial geomorphology Postglacial scenarios

Cannabinoids and endocannabinoids as therapeutics for nervous system disorders:preclinical models and clinical studies

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Neural regeneration research 2024年第4期19卷 788-799页

作者： r.Scott Duncan Sean m.riordan matthew C.Gernon Peter Koulen Department of Ophthalmology School of MedicineUniversity of Missouri Department of Biomedical Sciences School of MedicineUniversity of Missouri

Cannabinoids are lipophilic substances derived from Cannabis sativa that can exert a variety of effects in the human *** have been studied in cellular and animal models as well as in human clinical trials for their therapeutic benefits in several human *** of these include central nervous system(CNS)diseases and dysfunctions such as forms of epilepsy,multiple sclerosis,Parkinson’s disease,pain and neuropsychiatric *** addition,the endogenously produced cannabinoid lipids,endocannabinoids,are critical for normal CNS function,and if controlled or modified,may represent an additional therapeutic avenue for CNS *** review discusses in vitro cellular,ex vivo tissue and in vivo animal model studies on cannabinoids and their utility as therapeutics in multiple CNS *** addition,the review provides an overview on the use of cannabinoids in human clinical trials for a variety of CNS *** and endocannabinoids hold promise for use as disease modifiers and therapeutic agents for the prevention or treatment of neurodegenerative diseases and neurological disorders.

关键词： anandamide cannabidiol cannabinoid endocannabinoid epilepsy multiple sclerosis neurodegeneration neuroprotection tetrahydrocannabinol

Prediction of the undrained shear strength of remolded soil with non-linear regression,fuzzy logic,and artificial neural network

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Journal of mountain Science 2024年第9期21卷 3108-3122页

作者： YÜNKÜL Kaan KArAÇOr Fatih GÜrBÜZ Ayhan BUDAK TahsinÖmür Department of Civil Engineering Faculty of Engineering and ArchitectureTokat Gaziosmanpaşa UniversityTokat 60100Türkiye Department of Civil Engineering Faculty of Engineering and ArchitectureKafkas UniversityKars 36000Türkiye Department of Civil Engineering Faculty of EngineeringGazi UniversityAnkara 06570Türkiye ministry of Youth and Sports Ankara 06090Türkiye

This study aims to predict the undrained shear strength of remolded soil samples using non-linear regression analyses,fuzzy logic,and artificial neural network modeling.A total of 1306 undrained shear strength results from 230 different remolded soil test settings reported in 21 publications were collected,utilizing six different measurement *** water content,plastic limit,and liquid limit were used as input parameters for fuzzy logic and artificial neural network modeling,liquidity index or water content ratio was considered as an input parameter for non-linear regression *** non-linear regression analyses,12 different regression equations were derived for the prediction of undrained shear strength of remolded ***-Forward backpropagation and the TANSIG transfer function were used for artificial neural network modeling,while the mamdani inference system was preferred with trapezoidal and triangular membership functions for fuzzy logic *** experimental results of 914 tests were used for training of the artificial neural network models,196 for validation and 196 for *** was observed that the accuracy of the artificial neural network and fuzzy logic modeling was higher than that of the non-linear regression ***,a simple and reliable regression equation was proposed for assessments of undrained shear strength values with higher coefficients of determination.

关键词： Undrained shear strength Liquidity index Water content ratio Non-linear regression Artificial neural networks Fuzzy logic

Effect of solidification cooling rate on microstructure and tribology characteristics of Zn-4Si alloy

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International Journal of minerals,metallurgy and materials 2024年第2期31卷 362-373页

作者： F.Akbari m.Golkaram S.Beyrami G.Shirazi K.mantashloo r.Taghiabadi m.Saghafi Yazdi I.Ansarian Department of metallurgy and material Science Imam Khomeini International University(IKIU)Qazvin ***Iran

The main objective of this work was to modify the microstructure and enhance the tribological properties of a new Zn-4Si al-loy through a high solidification cooling rate(SCr).According to the results,by increasing the SCr from 2.0 to 59.5℃/s the average size of primary Si particles and that of the grains reduced from 76.1 and 3780μm to less than about 14.6 and 460μm,***-ing the SCr also enhanced the microstructural homogeneity,decreased the porosity content(by 50%),and increased the matrix hardness(by 36%).These microstructural changes enhanced the tribological *** instance,under the applied pressure of 0.5 mPa,an in-crease in the SCr from 2.0 to 59.5℃/s decreased the wear rate and the average friction coefficient of the alloy by 57%and 23%,*** wear mechanism was also changed from the severe delamination,adhesion,and abrasion in the slowly-cooled alloy to the mild tribolayer delamination/abrasion in the high-cooling-rate-solidified sample.

关键词： zinc-silicon alloy primary silicon solidification cooling rate tribology sliding wear

Identifying the validity domain of machine learning models in building energy systems

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Energy and AI 2024年第1期15卷 328-341页

作者： martin rätz Patrick Henkel Phillip Stoffel rita Streblow Dirk müller rWTH Aachen University E.ON Energy Research CenterInstitute for Energy Efficient Buildings and Indoor ClimateMathieustraβe 10Aachen52074Germany

The building sector significantly contributes to climate *** improve its carbon footprint,applications like model predictive control and predictive maintenance rely on system ***,the high modeling effort hinders practical *** learning models can significantly reduce this modeling *** ensure a machine learning model’s reliability in all operating states,it is essential to know its validity *** states outside the validity domain might lead to extrapolation,resulting in unpredictable *** paper addresses the challenge of identifying extrapolation in data-driven building energy system models and aims to raise knowledge about *** that,a novel approach is proposed that calibrates novelty detection algorithms towards the machine learning *** novelty detection algorithms are identified through a literature review and a benchmark test with 15 candidates.A subset of five algorithms is then evaluated on building energy ***,on two-dimensional data,displaying the results with a novel visualization *** on more complex multi-dimensional use *** methodology performs well,and the validity domain could be *** visualization allows for a profound analysis and an improved understanding of the fundamental effects behind a machine learning model’s validity domain and the extrapolation regimes.

关键词： Extrapolation detection Validity domain Novelty detection machine learning Artificial neural network Data-driven model predictive control Building energy systems

resistance of full-scale beams against close-in *** modeling and field tests

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Defence Technology（防务技术） 2024年第10期40卷 35-47页

作者： A.Prado A.Alañón r.Castedo A.P.Santos L.m.López m.Chiquito m.Bermejo C.Oggeri Escuela Politécnica Superior déAvila Universidad de SalamancaÁvila05003Spain E.T.S.I.minas y Energía Universidad Politecnica de MadridMadrid28003Spain Department of Engineering Aviation and TechnologySaint Louis UniversityMadrid28003Spain Department of Environment Land and Infrastructure Engineering(DIATI)Politecnico di TorinoTorino10129Italy

This paper explores the performances of a finite element simulation including four concrete models applied to a full-scale reinforced concrete beam subjected to blast *** test data has been used to compare model results for each *** numerical modelling has been,carried out using the suitable code *** code integrates blast load routine(CONWEP)for the explosive description and four different material models for the concrete including:Karagozian&Case Concrete,Winfrith,Continuous Surface Cap model and riedeleHiermaiereThoma models,with concrete meshing based on 10,15,and 20 *** full-scale beams were tested:four of them used for the initial calibration of the numerical model and two more tests at lower scaled *** calibration,field data obtained employing pressure and accelerometers transducers were compared with the results derived from the numerical *** surfaces and the shape of rupture in the beams have been used as references for *** of the meshing on accelerations has been put in evidence and for some models the shape and size of the damage in the beams produced maximum differences around 15%.In all cases,the variations between material and mesh models are shown and discussed.

关键词： Blast test Numerical simulation LS-DYNA Concrete model mesh effect Full-scale beams

Influence of the zigzag fins and inlet arrangements on the cooling proficiency of the mini-channel heat sink

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Propulsion and Power research 2024年第2期13卷 194-206页

作者： A.Torbatinezhad Y.Pahamli m.J.Hosseini r.Bahrampoury School of mechanical Engineering Babol University of TechnologyBabolIran Department of mechanical Engineering Semnan UniversitySemnanIran Department of mechanical Engineering Faculty of EngineeringGolestan UniversityGorganIran Department of mechanical Engineering K.N.Toosi University of TechnologyTehranIran

mini-channel heatsinks are one of the most effective thermal management methods for high heatﬂux devices due to the high performance of convective heat *** recent years,various techniques have been innovated to improve the thermal proﬁciency of the mini-channel *** of these are taking advantage ofﬁns’structural designs and ar-rangements of inlets and *** zigzagﬁns and channels were considered in the previous works in heatsinks,and researchers analyzed their cooling enhancement ***,in the present work,a combined cooling technique,considering new-type zigzagﬁns’geometrical parameters(arrangement,length,and height)causes turbulenceﬂow and higher convective heat transfer along with different positionings ofﬂow inlet and outlets resulting in superior temper-ature uniformity,is proposed to evaluate their impacts on the cooling proﬁciency of the heat sink versus different reynolds *** assess the thermal and hydraulic performance of the proposed heatsink,different parameters,including temperature contours,Nusselt numbers,thermal resistance,and entropy generation are *** a result,it is observed that in the case demonstrating the best thermal performance,the Nusselt number,pressure drop,thermal resistance,and entropy generation are respectively 37.13,4586.46 Pa,0.000078 m^(2)·K/W,and 0.1078 W/K in the best *** well,it is found that by changing the arrangements of inlets and outlets,the Nusselt number,and thermal resistance are improved by 12%and 13%,***,the proposed mini-channel heat sink could be used as a high-performance thermal management system for electronic devices in different industries,including energy,solar,and medical sectors.

关键词： Thermal management Heat transfer enhancement mini-channel heatsink Zigzagﬁn Entropy generation Electronic cooling

ranking environmental and edaphic attributes driving soil microbial community structure and activity with special attention to spatial and temporal scales

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mLife 2024年第1期3卷 21-41页

作者： Vadakattu V.S.r.Gupta James m.Tiedje CSIrO Agriculture&Food UrrbraeSouth AustraliaAustralia Centre for microbial Ecology Michigan State UniversityEast LansingMichiganUSA

The incredibly complex soil microbial communities at small scales make their analysis and identification of reasons for the observed structures *** community structure is mainly a result of the inoculum(dispersal),the selective advantages of those organisms under the habitat-based environmental attributes,and the ability of those colonizers to sustain themselves over *** soil is protective,and its microbial inhabitants have long adapted to varied soil conditions,significant portions of the soil microbial community structure are likely ***,a substantial portion of the community will not correlate to often measured soil *** suggest that the drivers be ranked on the basis of their importance to the fundamental needs of the microbes:(i)those that supply energy,i.e.,organic carbon and electron acceptors;(i)environmental effectors or stressors,i.e.,pH,salt,drought,and toxic chemicals;(ii)macro-organism associations,i.e.,plants and their seasonality,animals and their fecal matter,and soil fauna;and(iv)nutrients,in order,N,P,and probably of lesser importance,other micronutrients,and *** relevance of drivers also varies with spatial and time scales,for example,aggregate to field to regional,and persistent to dynamic populations to transcripts,and with the extent of phylogenetic difference,hence phenotypic differences in organismal *** present a summary matrix to provide guidance on which drivers are important for particular studies,with special emphasis on a wide range of spatial and temporal scales,and illustrate this with genomic and population(rrNA gene)data from selected studies.

关键词： abundance community structure diversity functional microbiome microorganisms