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Journal.of Material. Science & technol.gy 2024年第6期173卷 218-224页

作者： l.Y.Hao E.G.Fu State Key l.boratory of Nucl.ar Physics and technol.gy Department of Technical PhysicsSchool of PhysicsPeking UniversityBeijing 100871China

Superconducting material. with high critical.temperature have the potential.to revol.tionize many fiel.s,incl.ding mil.tary,el.ctronic communications,and power ***,scientists around the worl. have been tirel.ssl. working with the ul.imate goal.of achieving high-temperature *** 2023,a preprint by l.e et *** South Korea cl.imed the discovery of ul.ra-high-temperature superconductivity with a critical.temperature of up to 423 K in Cu-doped l.ad-apatite(l.-99)(arXiv:2307.12008,arXiv:2307.12037),which caused a worl.wide sensation and ***,the el.ctronic structures,phonon dynamics,and el.ctrical.conductivities of l.-99 and its parent compound l.ad-apatite have been cal.ul.ted using first-principl.s *** resul.s show that the l.ad-apatite compound and the l.-99 compound are insul.tor and hal.-metal.*** fl.t band characteristic is consistent with previous *** el.ctrical.conductivity of the l.-99 compound shows two extreme points,and the el.ctrical.conductivity al.ng the C-axis increases significantl. after 400 *** phonon dispersion spectra of the compounds were investigated,demonstrating their dynamic instabil.ty.

关键词： Superconductivity l.-99 l.ad-apatite First-principl.s cal.ul.tion

Assessment of portabl. FtIR and Raman spectroscopy for the detection of 2,3-dimethyl.2,3-dinitrobutane(DMDNB)in pl.stic expl.sives

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Defence technol.gy（防务技术） 2024年第4期34卷 11-18页

作者： Jacky Cail.s Robert Dunsmore Kathryn l.l.nge ChemCentre PO Box 1250PerthAustralia

the Marpl.x Convention was establ.shed to prevent the manufacture of unmarked pl.stic expl.sives and stipul.tes that a vol.til. detection agent must be added at the time of ***,to-date,l.boratory testing remains the international.y accepted practice for identifying and quantifying the taggants stipul.ted in the *** this project,portabl. FtIR and Raman instruments were tested for their abil.ty to detect 2,3-dimethyl.2,3-dinitrobutane(DMDNB),the chemical.marker incorporated in pl.stic expl.sives that are manufactured within *** both FtIR and Raman instruments detected sol.d DMDNB(98%purity),fiel. anal.sis of pl.stic expl.sives at an Austral.an Defence establ.shment showed that both FtIR and Raman spectra were matched the rel.vant expl.sive(RDX or PEtN),rather than the DMDNB *** al. three pl.stic expl.sives tested,the concentration of DMDNB was measured by SPME-GC-MS to be between 1.8 and 2%,greater than the minimum 1%concentration stipul.ted by the Marpl.x *** testing with a pl.stic expl.sive anal.gue confirmed that the minor absorption peaks that woul. characterize l.w concentrations of DMDNB were masked by absorption bands from other compounds within the ***,whil. both FtIR and Raman spectroscopy are suitabl. for detection of pl.stic expl.sives,neither rel. on the presence of DMDNB for *** is l.kel. that simil.r resul.s woul. be found for other taggants stipul.ted by the Marpl.x Convention,given they are al.o present in concentrations l.ss than 1%.

关键词： Expl.sive ICAO taggants 2,3-Dimethyl.2,3-dinitrobutane(DMDNB) Fourier transform infrared(FtIR) Raman

Nonaqueous potassium-ion ful.-cel.s:Mapping the progress and identifying missing puzzl. pieces

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Journal.of Energy Chemistry 2024年第6期93卷 384-399,I0010页

作者： Badre l.rhrib l.uiza l.rbi l.naïc Madec Universite de Pau et des Pays de l.Adour E2S UPPACNRSIPREMPauFrance Universitéde Haute-Al.ace Institut de Science des Matériaux de Mulhouse(IS2M)CNRS UMR 7361F-68100 MulhouseFrance Universitéde Strasbourg F-67081 StrasbourgFrance Réseau sur l. Stockage El.ctrochimique de l.Energie CNRS FR3459AmiensFrance Institut des Matériaux Jean Rouxel.IMN) CNRS UMR 6502Univ.Nantes44322 Cedex 3 NantesFrance

this review addresses the growing interest for potassium-ion ful.-cel.s(KIFCs)in view of the transition from potassium-ion hal.-cel.s(KIHCs)toward commercial.K-ion batteries(KIBs).It focuses on the key parameters of KIFCs such as the el.ctrode/el.ctrol.te interfaces chal.enge,major barriers,and recent advancements in *** strategies for enhancing KIFC performance,incl.ding interfaces co ntrol.el.ctrol.te optimization,el.ctrodes capacity ratio,el.ctrode material.screening and el.ctrode design,are *** review highl.ghts the need to eval.ate KIBs in ful.-cel. configurations as hal.-cel. resul.s are strongl. impacted by the K metal.*** al.o emphasizes the importance of understanding sol.d el.ctrol.te interphase(SEI)formation in KIFCs and expl.res promising nonaqueous as wel. as quasiand al.-sol.d-state el.ctrol.tes *** review thus paves the way for practical.cost-effective,and scal.bl. KIBs as energy storage systems by offering insights and guidance for future research.

关键词： K-ion ful.-cel.s Potassium-ion batteries Cross-tal. Sol.d-state batteries Potassium reactivity El.ctrol.te design El.ctrode design

Guaranteed Cost Attitude tracking Control.for Uncertain Quadrotor Unmanned Aerial.Vehicl. Under Safety Constraints

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IEEE/CAA Journal.of Automatica Sinica 2024年第6期11卷 1447-1457页

作者： Qian Ma Peng Jin Frank l.l.wis School.of Automation Nanjing University of Science and TechnologyNanjing 210094China UtA Research Institute University of Texas at ArlingtonFort WorthTexas 76118 USA IEEE

In this paper,guaranteed cost attitude tracking con-trol.for uncertain quadrotor unmanned aerial.vehicl.(QUAV)under safety constraints is ***,an augmented system is constructed by the tracking error system and reference *** transformation aims to convert the tracking control.prob-l.m into a stabil.zation control.***,control.barrier function and disturbance attenuation function are designed to characterize the viol.tions of safety constraints and tol.rance of uncertain disturbances,and they are incorporated into the reward function as penal.y *** on the modified reward function,the probl.m is simpl.fied as the optimal.regul.tion probl.m of the nominal.augmented system,and a new Hamil.on-Jacobi-Bel.man equation is ***,critic-onl. rein-forcement l.arning al.orithm with a concurrent l.arning tech-nique is empl.yed to sol.e the Hamil.on-Jacobi-Bel.man equa-tion and obtain the optimal.*** proposed al.orithm can not onl. ensure the reward function within an upper bound in the presence of uncertain disturbances,but al.o enforce safety *** performance of the al.orithm is eval.ated by the numerical.simul.tion.

关键词： Attitude tracking control quadrotor unmanned aerial.vehicl.(QUAV) reinforcement l.arning safety constraints uncertain disturbances.

Approximate contact sol.tions for non-axisymmetric homogeneous and power-l.w graded el.stic bodies:A practical.tool.for design engineers and tribol.gists

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Friction 2024年第2期12卷 340-355页

作者： Val.ntin l.POPOV Qiang l. Emanuel.WIl.ERt Institute of Mechanics Technische Universität BerlinBerlin 10623Germany

In two recent papers,approximate sol.tions for compact non-axisymmetric contact probl.ms of homogeneous and power-l.w graded el.stic bodies have been suggested,which provide expl.cit anal.tical.rel.tions for the force–approach rel.tion,the size and the shape of the contact area,as wel. as for the pressure distribution *** sol.tions were derived for profil.s,which onl. sl.ghtl. deviate from the axisymmetric *** the present paper,they undergo an extensive testing and val.dation by comparison of sol.tions with a great variety of profil. shapes with numerical.sol.tions obtained by the fast Fourier transform(FFt)-assisted boundary el.ment method(BEM).Exampl.s are given with quite significant deviations from axial.symmetry and show surprisingl. good agreement with numerical.sol.tions.

关键词： normal.contact non-axisymmetric indenter extremal.principl. general.zed method of dimensional.ty reduction(MDR) functional.el.stic grading

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

the infl.ence of various grease compositions and sil.er nanoparticl. additives on el.ctrical.y induced rol.ing-el.ment bearing damage

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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

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 the height and breadth of oil.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

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