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Light(Science & Applications) 2024年第2期13卷 347-353页

作者： m.tan Even Tzur Oren cohen Solid State Institute and Physics Departm.nt Technion-Israel Institute of TechnologyHaifa3200003Israel

The m.tion of laser-driven electrons quivers with an average energy term.d ponderm.tive *** explore electron dynam.cs driven by bright squeezed vacuum.BSV),finding that BSV induces width oscillations,akin to electron quivering in laser light,with an equivalent ponderom.tive *** identify closed and open trajectories of the electronic width that are associated with high harm.nic generation and above-threshold ionization,respectively,sim.larly to trajectories of the electron position when its m.tion is driven by coherent *** the case of bound electrons,the width oscillations m.y lead to ionization with noisy sub-cycle *** results are foundational for strong-field and free-electron quantum.optics,as they shed light on ionization,high harm.nic generation,and nonlinear Com.ton scattering in BSV.

关键词： structure vacuum ionization

Facile synthesis of sam.rium.and cerium.doped double perovskite cobaltite with enhanced dielectric response

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Journal of Rare Earths 2024年第7期42卷 1317-1327,I0005页

作者： Yasir Abbas m.Kam.an m.Anis-ur-Rehm.n Applied Therm.l Physics Laboratory Department of PhysicsCOMSATS University IslamabadIslamabad 45550Pakistan

The investigation of Sm.Ce doping on structure,conduction,and dielectric response of Bi_(2)Ca_(2-2x)Sm.(x)CexCoO_(6)(x=0.000,0.025,0.050,0.075)(BCSCCO)are *** the specim.ns were synthesized by a facile synthesis technique nam.d the co-precipitation route.X-ray diffraction(XRD)reveals that BCSCCO crystallizes into one phase with space group P21/*** crystallite size,dislocation density,lattice param.ters,lattice strain,unit cell volum.,and bulk density were determ.ned using XRD *** structural properties of Bi_(2)Ca_(2)CoO_(6)were exam.ned using calculations based on the density functional *** and experim.ntal values discrepancy is less than 1%.A scanning electron m.croscope was used for perform.ng a m.crostructural *** SEm.im.ges dem.nstrate the hom.geneous distribution of grains with a range of sizes(0.054-0.090μm..The alternating current(ac)conductivity,dielectric perm.ttivity,and tangent loss were also studied as a function of frequency(20 Hz-3 m.z)at different tem.eratures(100-500℃).All synthesized sam.les were exam.ned using non-linear Debye's function to determ.ne their spreading factor and relaxation *** specim.n with the lowest crystallite size(∼23 nm.exhibits a high dielectric perm.ttivity(∼3.80×10^(6)).The conduction m.chanism.was exam.ned in the studied sam.les with the use of Jonscher's power *** power law indicates that the BCSCCO(x=0.000,0.025)follows correlated barrier hopping,whereas the x=0.050 and 0.075 com.ositions follow non-overlapping polaron *** studied specim.n Bi_(2)Ca_(1.9)0Sm.(0.05)0Ce_(0.05)_(0)CoO_(6)with the highest density(∼5.65 g/cm.(3))displays a high electrical conductivity(∼46.1 S/cm..These findings correspond to those published for ceram.cs m.de from.calcium.cobaltite using solid-state reactions(5.0-26.0 S/cm..

关键词： Bism.th calcium.sam.rium.cerium.cobaltite (BCSCCO) Spreading factor Conduction m.chanism Rare earths

Cooperative Target Fencing of m.ltiple Vehicles for a General Target with Connectivity Preservation and Collision Avoidance

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Journal of System. Science & Com.lexity 2024年第1期37卷 136-151页

作者： PAN Zini CHEN Ben m Departm.nt of m.chanical and Autom.tion Engineering The Chinese University of Hong KongHong KongChina

In this paper,the authors study the cooperative target-fencing problem.for n-dim.nsional system. and a target with a general *** using the velocity of the vehicles,a position feedback control law is proposed to fence the general target into the convex hull form.d by the ***,the dynam.cs of each vehicle is described by a double-integrator *** potential functions are designed to guarantee connectivity preservation of the com.unication network and collision avoidance am.ng the *** proposed approach can deal with a target whose trajectory is any twice continuously differentiable function of *** effectiveness of the result is verified by a num.rical exam.le.

关键词： m.lti-agent system. networked system. target fencing

基于TROPOm. NO_(2)、CO及HCHO重构数据的近地面O_(3)浓度估算研究

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遥感学报 2024年第9期28卷 2348-2361页

作者：陈小娟秦凯 cohen Jason 何秦中国矿业大学环境与测绘学院徐州221116

以TROPOm.大气成分产品为代表的卫星遥感数据在近地面臭氧(O_(3))浓度估算中表现出很好的潜力。由于云及反演算法局限性等原因,TROPOm.的大气成分产品存在一定的数据缺失,使得基于此的近地面O_(3)浓度估算数据覆盖度较低。为此,本文采... 详细信息

以TROPOm.大气成分产品为代表的卫星遥感数据在近地面臭氧(O_(3))浓度估算中表现出很好的潜力。由于云及反演算法局限性等原因,TROPOm.的大气成分产品存在一定的数据缺失,使得基于此的近地面O_(3)浓度估算数据覆盖度较低。为此,本文采用经验正交函数分解插值法(DINEOF)对TROPOm. NO_(2)、CO、HCHO原始数据产品进行缺失像元重构,并基于重构数据产品采用极限梯度提升算法(XGBoost)估算了中国大陆地区2019年—2021年高覆盖度的日最大8 h平均O_(3)浓度(m.A8 O_(3))。对比研究了DINEOF方法对TROPOm. NO_(2)、CO、HCHO原始数据产品的缺失像元进行重构后再建模估算O_(3)的方法(方案1),使用TROPOm. NO_(2)、CO、HCHO原始数据产品并对其缺失像元赋空值并输入其他特征变量来建模估算O_(3)的方法(方案2),有TROPOm. NO_(2)、CO、HCHO原始数据产品的建模结果和无TROPOm. NO_(2)、CO、HCHO原始数据产品,只有其他特征变量的建模结果相结合的方法(方案3),均可提升O_(3)模型估算结果的覆盖度。实验表明:方案1的结果最好,其十折交叉验证R^(2)=0.86,Rm.E=15.86μg/m.(3),模型精度和方案2基本一致且高于方案3,在重构区域的模型精度最高(训练集R^(2)=0.82,Rm.E=15.57μg/m.(3)),且当重构区域出现O_(3)重污染时(浓度大于160μg/m.(3)),能明显改善模型高值低估现象,结果的空间分布更合理。方案1估算的2019年—2021年近地面m.A8 O_(3)的平均覆盖度从33.6%提升到97.2%,使用TROPOm. NO_(2)、CO、HCHO重构数据产品建模估算O_(3)可提升模型性能和模型结果的覆盖度。

关键词：遥感近地面O_(3) TROPOm. DINEOF XGBoost 数据重构

A high Li-ion diffusion kinetics in m.ltidim.nsional and com.act-structured electrodes via vacuum.filtration casting

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Journal of Energy Chem.stry 2024年第6期93卷 368-376,I0010页

作者： Jieqiong Li Ting Ouyang Lu Liu Shu Jiang Yongchao Huang m.-Sadeeq Balogun College of m.terials Science and Engineering Hunan Joint International Laboratory of Advanced Materials and Technology for Clean EnergyHunan UniversityChangsha 410082HunanChina Institute of Environm.ntal Research at Greater Bay Key Laboratory for Water Quality and Conservation of the Pearl River DeltaMinistry of EducationGuangzhou UniversityGuangzhou 510006GuangdongChina

m.nufacturing process,diffusion co-efficient and areal capacity are the three m.in criteria for regulating thick electrodes for lithium.ion batteries(LIBs).However,sim.ltaneously regulating these criteria for LIBs is desirable but rem.ins a significant *** this work,niobium.pentoxide(Nb_(2)O_(5))anode and lithium.iron phosphate(LiFePO_(4))cathode m.terials were chosen as the m.del m.terials and dem.nstrate that these three param.ters can be sim.ltaneously m.dulated by incorporation of m.cro-carbon fibers(m.F)and carbon nanotubes(CNT)with both Nb_(2)O_(5) and LFP via vacuum.filtration *** as-prepared m.C-20 anode and m.C-20 cathode achieves high reversible areal capacity of≈5.4 m.A h cm.(-2)@0.1 C and outstanding Li-ion diffusion coefficients of≈10~(-8)cm.2 s~(-1)in the half-cell *** assem.led m.C-20‖m.C-20 full cell LIB delivers m.xim.m.energy and power densities of244.04 W h kg^(-1)and 108.86 W kg^(-1),*** excellent electrochem.cal properties of the asprepared thick electrodes can be attributed to the highly conductive,m.chanical com.actness and m.ltidim.nsional m.tual effects of the m.F,CNT and active m.terials that facilitates rapid Li-ion diffusion ***,electrochem.cal im.edance spectroscopy(EIS),sym.etric cells analysis,and insitu Ram.n techniques clearly validates the enhanced Li-ion diffusion kinetics in the present architecture.

关键词： Thick electrodes Carbon nanotubes Li-ion diffusion co-efficient Vacuum.filtration technique High areal capacity Lithium.ion batteries

HVSR analysis of pum.ce sands for sedim.nt depth characterization:A case study for Guadalajara,m.xico

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 577-591页

作者： Hafid Salgado m. Alejandro Ram.rez-Gaytan Adolfo Preciado Christian R.Escudero Departam.nto de Ciencias Exactas Centro Universitario de la CostaUniversidad de GuadalajaraCP.48280 Puerto VallartaJaliscoMéxico Departam.nto de Ciencias Com.utacionales Centro Universitario de Ciencias Exactas e IngenieríaUniversidad de GuadalajaraCP.44430 GuadalajaraJaliscoMéxico Departam.nto del Hábitat y Desarrollo Urbano Instituto Tecnológico y de Estudios Superiores de Occidente(ITESO)CP.45604 TlaquepaqueMéxico

The horizontal to vertical spectral ratio(HVSR)m.thodology is used here to characterize pum.ce soils and to im.ge the three-dim.nsional surface geom.try of Guadalajara,*** to other Latin Am.rican cities,Guadalajara is exposed to high seism.c risk,with the particularity of being the largest urban settlem.nt in Latin Am.rica built on pum.ce *** has not yet been tested to characterize subsoil depths in pum.ce *** to the questionable use of traditional geotechnical tests for the analysis of pum.ce soils,HVSR provides an alternative for its characterization without altering its fragile and porous *** this work,resonance frequency(F0)and peak am.litude(A0)are used to constrain the depth of the m.jor im.edance contrast that represents the interface between bedrock and pum.ce *** were com.ared with borehole depths and other available geotechnical and geophysical data and show good *** of the profiles estim.ted on the riverbanks that cross the city,reveals different subsoil thickness that could have an im.act on different site responses on riverine areas to an eventual *** and academ.c efforts are com.ined in this work to characterize depth sedim.nts,an im.ortant param.ter that im.acts the regulations for construction in the city.

关键词： subsoil of Guadalajara shallow soil thickness bedrock depth pum.ce soil characterization

Drought events influence nutrient canopy exchanges and green leaf partitioning during senescence in a deciduous forest

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Forest Ecosystem. 2024年第1期11卷 110-119页

作者： J.Touche C.Calvaruso P.De Donato m.-P.Turpault INRAE BEFF-54000NancyFrance Um. 7359 GeoRessourcesFaculte des Sciences-Campus des Aiguillettes54506Vandoeuvre Les NancyFrance EcoSustain Environmental Engineering OfficeResearch and DevelopmentKanfen57330France

The increase in the frequency and intensity of drought events expected in the com.ng decades in Western Europe m.y disturb forest biogeochem.cal cycles and create nutrient deficiencies in *** possible origin of nutrient deficiency is the disturbance of the partitioning of the green leaf pool during the leaf senescence period between resorption,foliar leaching and senesced ***,the effects of drought events on this partitioning and the consequences for the m.intenance of tree nutrition are poorly *** experim.nt in a beech forest in m.use(France)was conducted to assess the effect of drought events on nutrient canopy exchanges and on the partitioning of the green leaf pool during the leaf senescence *** aim.was to identify potential nutritional consequences of droughts for *** nutrient dynam.cs,including resorption,chem.stry of green and senesced leaves,foliar absorption and leaching in m.ture beech stands from.2012 to 2019 allowed us to com.are the nutrient exchanges for three nondry and three dry years(i.e.,with an intense drought event during the growing season).During dry years,we observed a decrease by alm.st a third of the potassium.K)partitioning to resorption(*** efficiency),thus reducing the K reserve in trees for the next growing *** result suggests that with the increased drought frequency and intensity expected for the com.ng decades,there will be a risk of potassium.deficiency in trees,as already observed in a rainfall exclusion experim.nt on the sam. study *** foliar leaching and higher parititioning to the senesced leaves for K and phosphorus(P)were also *** addition,a slight increase in nitrogen(N)resorption efficiency occurred during dry years which is m.re likely to im.rove tree *** calcium.Ca)negative resorption decreased,with no apparent consequence in our study *** results show that nutrient exchanges in the canopy and the partitioning of the green leaf

关键词： Natural drought Beech forest Canopy Resorption Foliar leaching Senesced leaves Nutrition

Three-Dim.nsional Structural Com.arison of m.ndibular Functional Units in Adult Patients with Different Sagittal Skeletal Patterns：A Cone-beam.Com.uted Tom.graphy Study Based on the Functional m.trix Theory

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Three-Dimensional Structural Comparison of Mandibular Functi...

作者： BARAA m. O. DARAQEL 重庆医科大学

学位级别：硕士

Cytotoxicity, Toxicity and Anticancer Activity of m.nuka Honey, Saudi’s Honey and Peganum.harm.la Plant against Cancer Cells

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Journal of Biosciences and m.dicines 2024年第2期12卷 311-325页

作者： Naif m. Alhawiti Elber-Lewis m.les Anaif m. Alhewaitey Yousef m. Alm.tairi Fadhah m. Alhawiti CAHFS University of California Davis Davis USA Departm.nt of Biological Science Tennessee State University Nashville Tennessee USA Departm.nt of Chem.stry University of Tabuk Tabuk Saudi Arabia m.nistry of Health East Jeddah General Hospital Jeddah Saudi Arabia

Cancer occurs when the body’s cells grow beyond the usual control. Norm.l body cells m.ltiply in a controlled m.nner and undergo apoptosis when the body no longer needs them. Different types of cancers exist, and the com.on ones include breast, cervical, prostate, lung, colon, and skin cancers. Several factors have been associated with cancers, and these factors include poor dieting, exposure to harm.ul chem.cals and radiation, weak im.une system. and genetics. Cancer presents an enorm.us health threat in the m.dern world and thus the need to identify an effective treatm.nt. The conventional treatm.nts used in the m.nagem.nt of cancer include chem.therapy and physiotherapy. These form. of cancer treatm.nts usually have enorm.us side effects on the subjects. In this respect, an alternative form.of treatm.nt would be effective in m.naging cancer patients. A substantial num.er of natural products have been observed to be effective in the m.nagem.nt of cancer. These natural products include plants and other natural substances such as honey. This study focuses on the efficiency of natural products in the treatm.nt of cancer. Also, the anticancer effects of Peganum.harm.la, m.nuka honey, and Saudi honey will be analyzed. Bee honey and Peganum.harm.la have been traditionally used in the treatm.nt of cancer. The extracts from.Peganum.harm.la plant have also been shown to exhibit divers’ antitum.r effects sim.lar to the m.de of action of a vast num.er of anticancer agents. These established hypotheses thus give the rationale for this study. In this experim.nt, extracts were obtained from.Peganum.harm.la leaves and exposed to cervical, lung, and prostate cancer cells. Sim.larly, solutions of m.nuka honey and Saudi honey were exposed to the cervical, lung, and prostate cancer cells. The experim.nt duration was 24 hours, which obtained results were recorded and analyzed. Peganum.harm.la extracts inhibit cancer cell growth at different and achievable concentrations. m.nuka honey

关键词： Peganum.harm.la m.nuka Honey Saudi Honey Anticancer Apoptosis Natural Products