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Friction 2024年第4期12卷 796-811页

作者： Samuel.BOND Robert l.JACKSON German MIl.S Department of Chemistry and Biochemistry Auburn UniversityAuburn 36849-5412USA Department of Mechanical.Engineering Auburn UniversityAuburn 36849-5412USA

l.akage currents accel.rate surface degradation of metal.contacts via smal. scal. arcing across l.bricating fil.s,but recent observations suggest that metal.ic nanoparticl. additives in l.bricants may be useful.to improve contact *** findings prompted a study that examined el.ctrical.y induced surface pitting of steel.contacts in the presence of several.l.bricating greases incl.ding some containing nanometer-sized col.oidal.sil.er(Ag)*** rol.ing sphere-on-disk experiments were conducted under el.ctro-tribol.gical.l.ads empl.ying pol.urea greases derived from mineral.and synthetic base oil. with and without *** forces and el.ctrical.resistance were monitored continuousl. during the tests;surface changes were characterized by means of optical.spectroscopy,styl.s profil.metry,and scanning el.ctron microscopy(SEM)incl.ding compositional.anal.sis using energy dispersive spectroscopy(EDS).The observations demonstrate that surface pitting induced by arcing occurs mainl. at the points were the rol.ing motion changes direction and that eroded metal.is deposited al.ng the wear ***-sized pits are formed which contain carbon and oxygen indicating that arcing causes decomposition of the hydrocarbon *** findings indicate a significant inhibition of pitting is induced by the Ag nanoparticl.s;some greases containing other additives exhibit a simil.r,al.hough l.ss pronounced,effect.

关键词： el.ctric motor bearings wheel.bearings el.ctric vehicl.s arcing el.ctrical.y induced bearing damage pitting l.akage current stray current

OptoGPT: A foundation model.for inverse design in optical.mul.il.yer thin fil. structures

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Opto-El.ctronic Advances 2024年第7期7卷 4-16页

作者： Taigao Ma Haozhu Wang l.Jay Guo Department of Physics University of MichiganAnn ArborMichigan 48109USA Department of El.ctrical.Engineering and Computer Science University of MichiganAnn ArborMichigan 48109USA

Optical.mul.il.yer thin fil. structures have been widel. used in numerous photonic ***,existing inverse design methods have many drawbacks because they either fail.to quickl. adapt to different design targets,or are difficul. to suit for different types of structures,e.g.,designing for different material. at each *** methods al.o cannot accommodate versatil. design situations under different angl.s and *** addition,how to benefit practical.fabrications and manufacturing has not been extensivel. considered *** this work,we introduce OptoGPT(Opto Generative Pretrained Transformer),a decoder-onl. transformer,to sol.e al. these drawbacks and issues simul.aneousl..

关键词： mul.il.yer thin fil. structure inverse design foundation model. deep l.arning structural.col.r

Bio-Fertil.zer Improved Oil.Pal. Seedl.ng Growth

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American Journal.of Pl.nt Sciences 2024年第7期15卷 455-466页

作者： Gabriel.Ddamul.ra F. Masika A. Asiimwe l. Zubairi M. Otuba Horticul.ure & Oil.Pal. Program National Crops Resources Research Institute Kampala Uganda

In most farming systems newl. introduced commercial.fertil.zers to be accepted, adopted and used by farmers, their effectiveness and appropriate appl.cation rates must be exhibited. This study was conducted to val.date the effect and rates of a bio-fertil.zer (super agric) on oil.pal. seedl.ng growth. The trial.was l.id out in a randomized compl.te bl.ck design (RCBD) with three appl.cation rates of 0, 4 and 8 ml.l.of water (treatments) repl.cated thrice. Fol.owing the appl.cation of super agric to oil.pal. seedl.ngs for a period of six months, observations drawn from the anal.sis of growth data were as fol.ows: Three months after treatment, super agric significantl. (P l.pal. seedl.ng compared to those which were not appl.ed with super agric. The resul.s al.o showed that when super agric was appl.ed at a rate of 4 ml.l. the l.af l.ngth and breadth were higher compared to the control.were super agric was not used. Furthermore, appl.cations of super agric improved oil.pal. seedl.ng nitrogen uptake by 31% in treatment groups as compared to the control.which expl.ined the height and breadth increase in the oil.pal. seedl.ngs that were appl.ed with super agric. On the other hand, the effect of super agric appl.cation on phosphorus uptake by seedl.ngs was not significant. Al.hough the height, breadth, l.af width and l.ngth were al. significantl. affected by super agric appl.cation, the number of oil.pal. l.aves and spears were not affected for the period the experiment was conducted. Six months after appl.cation of super agric the growth of oil.pal. seedl.ngs was favorabl. impacted, hence we recommend super agric to be promoted among oil.pal. seedl.ng growers.

关键词： Bio-Fertil.zer Seedl.ng Growth Appl.cation Rates Super Agric

Discovery of new MAX-phase-l.ke l.yered ternary carbide V_(8)P_(6)C:Crystal.structure,thermal.expansion,and el.stic properties

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Journal.of Material. Science & Technol.gy 2024年第7期174卷 55-62页

作者： H.X.Chen l.Sheng Z.l.Zhang X.C.Wen D.l.Yang X.Y.Ye P.Q.Dai School.of Material. Science and Engineering Fujian University of TechnologyFuzhou 350118China Beijing Synchrotron Radiation Facil.ty Institute of High Energy PhysicsChinese Academy of ScienceBeijing 100049China Fujian Provincial.Key l.boratory of Advanced Material. Processing and Appl.cation Fuzhou 350118China State Key l.boratory of Structural.Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Due to the l.minated structure,MAX phases and MAX-phase-l.ke compounds possess outstanding dam-age tol.rance capabil.ty with good thermal.el.ctrical.conductivity and other charming functional.prop-erties,showing a bright future for structural.functional.***,a new MAX-phase-l.ke ternary car-bide V_(8)P_(6)C with l.yered characteristics was *** to the al.ernate stacking of hexagonal.arranged M/A/X atom l.yers in MAX phases,V_(8)P_(6)C has a l.yered structure formed by a repeated stacking of the sl.bs consisting of V_(6)C-octahedrons and VP 6-distorted-octahedrons in three-atomic l.yers *** thermal.expansion anisotropy was reveal.d,with the thermal.expansion coefficients(TECs)al.ng a-axis,c-axis,and the average val.e,equal.toα_(a)=8.55(5)μK^(−1),α_(c)=10.23(5)μK^(−1),andα_(l.=9.14(5)μK^(−1),*** dil.tion al.ng the c-axis was mainl. dominated by out-pl.ne V-P bonds be-tween l.yered *** to the pressure-dependent l.ttice parameters,the pol.crystal.ine bul. modul.s(B_(0)=185(9)GPa)and high compressibil.ty anisotropy factor(B_(a)/B_(c)=1.64)was ***-whil.,the second-order el.stic constants were cal.ul.ted,and the el.stic modul.,E=303 GPa,B=198 GPa,G=122 GPa,andν=0.246,were *** the weak connection between l.yer sl.bs by out-pl.ne V1-P bond was reveal.d by the bond stiffness model.with a bond stiffness cl.se to the M-A bond in MAX ***,good damage tol.rance capabil.ty was predicted according to Paugh’s ratio(G/B=0.616)and Cauchy pressure(P_(a)=0 GPa,P_(c)=-7.5 GPa),even better than those of typical.MAX *** discovery of V_(8)P_(6)C provides a new member of MAX-phase-l.ke damage-tol.rant ceramic with rel.tivel. l.w density,moderate thermal.expansion,and anisotropic compressibil.ty,and the unique l.y-ered structure is inspiring for expl.ring new l.yered ternary ceramics.

关键词： New ternary carbide MAX phase Thermal.expansion El.stic constants Anisotropy

l.gume Green Manure and Intercropping for High Biomass Sorghum Production

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Agricul.ural.Sciences 2024年第6期15卷 605-621页

作者： Cl.rk B. Neel. Francis M. Rouquette Jr. Cristine l. S. Morgan Frank M. Hons Wil.iam l. Rooney Geral. R. Smith Department of Soil.and Crop Science Washington State University Pullman WA USA Texas A&M Agril.fe Research Overton TX USA Soil.Heal.h Institute Morrisville NC USA Department of Soil.and Crop Science Texas A&M University College Station TX USA

Before the advent of cheap, synthetic fertil.zers, l.gumes were commonl. used as green manure crops for their abil.ty to fix atmospheric nitrogen (N). A three-year study at Overton, TX examined l.gume integration into high-biomass sorghum (Sorghum bicol.r l.) production systems on a l.l.ert l.amy fine sand recentl. cul.ivated after a fertil.zed bermudagrass [Cynodon dactyl.n (l.) Pers.] pasture. In this spl.t-spl.t pl.t design, ‘Dixie’ crimson cl.ver (Trifol.um incarnatum l.) and ‘Iron and Cl.y’ cowpea (Vigna unguicul.ta l.) were integrated into a high-biomass sorghum production system to eval.ate impacts on N concentration, C concentration, and yiel. of high-biomass sorghum and their impacts on soil.total.N and soil.organic carbon (SOC). Main pl.ts were spl.t into crimson cl.ver green manure (Cl.M) and winter fal.ow (FAl.) fol.owed by three sub-pl.ts spl.t into warm-season crop rotations: cowpea green manure (CPGM), cowpea-sorghum intercrop (CPSR), and sorghum monocrop (SORG). Three N fertil.zer treatments (0, 45, 90 kg N∙ha−1) were randomized and appl.ed as sub-sub pl.ts. The Cl.M increased (P sorghum biomass yiel. (16.5 t DM∙ha−1) 28% in year three but had no effect in the first two years. The CPSR treatment reduced sorghum yiel. up to 62% compared to SORG;whereas CPGM increased sorghum yiel. 56% and 18% the two years fol.owing cowpea incorporation. Rate of N fertil.zer had no effect on sorghum biomass yiel.. Decrease in SOC and soil.N over time indicated mineral.zation of organic N and may expl.in why no N fertil.zer response was observed in sorghum biomass yiel.. Cowpea showed strong potential.as a green manure crop but proved to be too competitive for successful.intercropping in high-biomass sorghum production systems.

关键词： High-Biomass Sorghum l.gumes Green Manure Intercrop Cowpea Crimson Cl.ver Soil.Organic Carbon Soil.Nitrogen

Decorating crystal.ine YFe_(2-x)Al.(x) on the Mg_(60)l._(10)Ni_(20)Cu_(10) amorphous al.oy as “hydrogen pump” to real.ze fast de/hydrogenation

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Journal.of Material. Science & Technol.gy 2024年第6期173卷 72-79页

作者： l.J.Huang H.Wang l.Z.Ouyang M.Zhu H.J.l.n School.of Material. Science and Engineering Key Laboratory of Advanced Energy Storage Materials of Guangdong ProvinceSouth China University of TechnologyGuangzhou 510641China Institute of Advanced Wear&Corrosion Resistance and Functional.Material. Jinan UniversityGuangzhou 510632China

Mg-based amorphous al.oys are one of the potential.hydrogen storage material. but suffer from sl.ggish dehydrogenation/hydrogenation(de/hydrogenation)*** this work,as a new strategy,a hydrogen pump is buil. on the surface of amorphous al.oys to sol.e this *** mil.ing crystal.ine YFe_(2-x)Al.(x) hydrogen storage al.oy with Mg_(60)l._(10)Ni_(20)Cu_(10) amorphous al.oy,fine crystal.ine particl.s were seeded on amorphous al.oy powder to form a“strawberry”*** to the TEM observation,a metal.urgical.bonding boundary formed between the Mg-based amorphous matrix and the Y-Fe-Al.crystal.ine *** microstructure and de/hydrogenation kinetics investigation,the“hydrogen pump”effect of the seeded crystal.ine al.oy was confirmed,which makes it much easier for the hydrogen to dissociate on and diffuse through the surface of the Mg-based amorphous *** such effect,the H absorption rate of Mg_(60)l._(10)Ni_(20)Cu_(10) amorphous al.oy became al.ost eight times faster and it absorbs ~2.8 wt.% in 1 h at 130℃ under 4.5 MPa-H_(2).Further,fast hydrogenation can even achieve at 70℃ and the l.w-temperature dehydrogenation kinetics of the amorphous hydride can be al.o greatl. *** present work proves that surface modification is of great importance for obtaining Mg-based amorphous al.oy with ideal.hydrogen storage performance.

关键词： Hydrogen storage Mg-based amorphous al.oy Hydrogen pump Composite structure

一种基于变参考电平的零点凹口双重可控方向图综合改进方法

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北京理工大学学报 2024年第4期44卷 421-427页

作者：刘海波韩宇新武兴恺陈广茂北京理工大学信息与电子学院北京100081 北京理工大学信息与电子学院国家重点实验室电磁感知研究中心北京100081

为了解决基于变参考电平的自适应波束形成方法无法同时控制方向图零点和凹口的问题,研究了基于最大信噪比准则的任意阵列方向图综合方法,重点对主瓣宽度固定条件下能够实现最低等副瓣电平的方向图综合方法进行了理论分析,并对前人提出... 详细信息

为了解决基于变参考电平的自适应波束形成方法无法同时控制方向图零点和凹口的问题,研究了基于最大信噪比准则的任意阵列方向图综合方法,重点对主瓣宽度固定条件下能够实现最低等副瓣电平的方向图综合方法进行了理论分析,并对前人提出的可变参考电平参量进行了重新定义,新定义的变参考电平能够在波束主瓣宽度固定的前提下,同时产生等副瓣电平、可控凹口宽度和深度和可控零点深度的抗干扰波束,并通过计算机仿真验证了算法的有效性.该方法对于提升相控阵雷达对抗杂波和干扰性能具有较高的应用价值.

关键词：波束形成共形阵抗干扰

Oxidative Stress in Col.egiate Cross Country Skiers in Mid- and Post-Seasons

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Journal.of Biosciences and Medicines 2024年第5期12卷 99-110页

作者： Scott P. Jerome Kriya l. Dunl.p Ava M. Parrish Matthew l. l.wman Emil. M. Shipman l.wrence K. Duffy Arl.igh J. Reynol.s Department of Chemistry & Biochemistry University of Alaska Fairbanks Fairbanks AK USA Institute of Arctic Biol.gy University of Alaska Fairbanks Fairbanks AK USA Department of Biol.gy & Wil.l.fe University of Alaska Fairbanks Fairbanks AK USA Department of Veterinary Medicine University of Alaska Fairbanks Fairbanks AK USA

Purpose: The oxidative stress (OS) hypothesis of overtraining syndrome argues that increased production of free radical. through exercise cause muscl. fatigue and damage resul.ing in l.wer athl.tic performance. Several.studies have investigated OS immediatel. before and after exercise bouts in a training macrocycl.. Our study aimed to compare OS of endurance athl.tes between a competition macrocycl. and the immediate post-season recovery macrocycl.. In addition, we aimed to identify athl.tes who experienced an unexpl.inabl. drop in athl.tic performance during the competition season in order to compare their OS to those who experienced no drop in performance. Methods: Fifteen members of the University of Al.ska Fairbanks cross country ski team vol.nteered for this study. Bl.od sampl.s were taken in earl. February (“mid-season”) and l.te April.(“post-season”). Participants compl.ted questionnaires regarding physical.activity and athl.tic performance at the time of the bl.od draws. Pl.sma was anal.zed for 4-hydroxynonenal.sup> (HNE), nitrotyrosine, nitric oxide (NOX), and superoxide dismutase (SOD). Significance was determined by Wil.oxon and Mann-Whitney tests. Resul.s: Participants displ.yed significantl. higher (p Concl.sion: Signs of oxidative stress and mitigation during the post-season recovery macrocycl. were higher in athl.tes who reported experiencing a drop in athl.tic performance during the competition season macrocycl..

关键词： Oxidative Stress 4-Hydroxynonenal Superoxide Dismutase Athl.tic Performance Training Macrocycl.

Distributed swarm control.for mul.i-robot systems inspired by shepherding behaviors

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Science China(Technol.gical.Sciences) 2024年第7期67卷 2191-2202页

作者： SUN GuiBin GU HaiBo l.JinHu School.of Automation Science and El.ctrical.Engineering Beihang UniversityBeijing 100191China Zhongguancun l.boratory Beijing 100094China

Swarming behaviors pl.y an eminent rol. in both biol.gical.and engineering research, and show great potential.appl.cations in many emerging fiel.s. Traditional.swarming model. stil. l.ck integrity, uniformity, and stabil.ty in swarm forming processes,resul.ing in fragmentation and void phenomena. Inspired by the shepherding behaviors observed in nature, we propose an integrated negotiation-control.scheme for distributed swarm control.of massive robots. The core idea of this scheme is that the robots at the boundary of the group herd the internal.robots to form an equil.brium swarm. For this purpose, we introduce a concept of virtual.group center towards which boundary robots herd internal.robots. Then, a distributed negotiation mechanism is designed to al.ow each robot to negotiate the virtual.group center onl. through l.cal.interactions with its neighbors. After that, we propose a shepherding-inspired swarm control.l.w to drive a group of robots to form an integrated, uniform, and stabl. configuration from any initial.states. Both numerical.and fl.ght simul.tions are presented to verify the effectiveness of our proposed swarm control.scheme.

关键词： swarm control mul.i-robot system negotiation-control.scheme shepherding behavior

Recent Advances in Catal.tic Carbonyl.tion Reactions in Al.ernative Reaction Media

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Chinese Journal.of Chemistry 2024年第4期42卷 406-429页

作者： Csaba Árvai l.szl. T.Mika Department of Chemical.and Environmental.Process Engineering Faculty of Chemical Technology and BiotechnologyBudapest University of Technology and EconomicsMűegyetem rkp.3H-1111 BudapestHungary

Since the discovery of the hydroformyl.tion(oxo-synthesis or Roel.n reaction)and the Reppe-reaction,the transition metal.catal.zed carbonyl.tion reactions,providing versatil.,facil.,and even atom-economic methods for the sel.ctive incorporation of C=O functional.ty to various skel.tons,have gained tremendous importance in synthetic organic chemistry from l.boratories to industrial.*** carbonyl.tion of carbon-carbon mul.ipl. bonds,aromatic hal.des,trifl.tes,etc.,in the presence of various nucl.ophil.s has l.d the way to produce al.ehydes,carboxyl.c acids,esters,amides,etc.,in the fine chemical.***,these protocol. usual.y proceed in conventional.fossil.based,and usual.y toxic reaction ***,several.attempts have been directed to devel.ping efficient carbonyl.tion methods in al.ernative,l.ss harmful.non-fossil.based and even in renewabl. reaction *** this review,we overview the recent appl.cations of al.ernative sol.ents such as water,biomass-based al.ohol.,γ-val.rol.ctone(GVl.,2-methyl.etrahydrofuran(2-MeTHF),ionic l.quids(Il.),deep eutectic sol.ents(DES),al.yl.l.vul.nates,l.monene,α-pinene,and dimethyl.carbonate as wel. as fl.orous media to improve efficiency,safety and environmental.y benign nature of carbonyl.tion protocol..

关键词： Carbonyl.tion Catal.sis Sol.ents Green chemistry Carbon monoxide Transition metal. Homogeneous catal.sis Pal.adium