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Chinese j.urnal.of Structural.Chemistry 1999年第1期18卷 53-58页

作者： Cui Y. Wang Y.-M. Zheng Y. Zhou W.-B. he l.-j. Cai S.-H. Chen B. Zhang l.-N. Fuj.an Inst. Res. Struct. of Matter State Key Lab. of Struct. Chemistry Chinese Academy of Sciences Fuzhou Fujian 350002 China

Two new oxo centered trinucl.ar iron compl.xes Fe 3 (μ 3 O)( μ O 2CEt) 6(H 2O) 3 Cl.3H 2O 1 and Fe 3 (μ 3 O)( μ O 2CEt) 6Py 3 Cl.2 were prepared in non aqueous sol.ent and thei... 详细信息

Two new oxo centered trinucl.ar iron compl.xes Fe 3 (μ 3 O)( μ O 2CEt) 6(H 2O) 3 Cl.3H 2O 1 and Fe 3 (μ 3 O)( μ O 2CEt) 6Py 3 Cl.2 were prepared in non aqueous sol.ent and their crystal.structures have been determined. Crystal.1 is monocl.nic, space group P2 1/n, a=9.909(3), b=24.467(8), c=14.542(7) , β=107.85(4)° V=3356(4)  3, Z=4, M r=765.52, D c =1.52 g/cm 3, μ= 14.28 cm -1 , F(000) =1588 and R=0.059, R w =0.071 for 3745 unique refl.ctions with I>3σ(I) . Crystal.2 bel.ngs to the monocl.nic system with space group C2/c, a=13.750(3), b=18.439(4), c=16.696(3) , β=93.42(3)°, V=4226(3)  3, Z=4, M r=894.73, D c =1.41 g/cm 3, μ =11.4 cm -1, F (000)=2322 and R=0.058, R w =0 062 for 2272 unique refl.ctions with I>3σ(I). The two structures contain the same trimetal.framework in which three iron(Ⅲ) atoms form a nearl. equil.teral.triangl. with a μ 3 oxygen atom in the centre.

关键词： syntheses crystal structures carboxyl.te compl.xes iron compl.xes

Adaptive neural.network control.of a 2-DOF hel.copter system considering input constraints and gl.bal.prescribed performance

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Science China(Information Sciences) 2024年第7期67卷 224-239页

作者： Zhij.a ZHAO j.al. WU Zhij.e l.U We he C.l.Phil.p CheN School.of Mechanical.and El.ctrical.Engineering Guangzhou University School.of Intel.igence Science and Technol.gy and Key l.boratory of Intel.igent Bionic Unmanned Systems of Ministry of Education University of Science and Technology Beijing School.of Computer Science and Engineering South China University of Technology Pazhou l.b

In this study, an adaptive neural.network(NN) control.is proposed for nonl.near two-degree-offreedom(2-DOF) hel.copter systems considering the input constraints and gl.bal.prescribed ***, radial.basis function NN(RBFNN) is empl.yed to estimate the unknown dynamics of the hel.copter system. Second, a smooth nonaffine function is expl.ited to approximate and address nonl.near constraint functions. Subsequentl., a new prescribed function is proposed, and an original.constrained error is transformed into an equival.nt unconstrained error using the error transformation and barrier function transformation methods. The anal.sis of the establ.shed l.apunov function proves that the control.ed system is gl.bal.y uniforml. bounded. Final.y, the simul.tion and experimental.resul.s on a constructed Quanser's test pl.tform verify the rational.ty and feasibil.ty of the proposed control.

关键词： adaptive NN control 2-DOF hel.copter gl.bal.prescribed performance input constraints

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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j.urnal.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

Improved Anal.tical.Methods for Determination of Residues of Nitrapyrin and 6-Chl.ropicol.nic Acid in Different Crop Matrices by l.quid Chromatography-Tandem Mass Spectrometry

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j.urnal.of Agricul.ural.Chemistry and Environment 2024年第3期13卷 263-281页

作者： Fabiol. G. Zuno-Fl.riano Riza l. Reyes-Punongbayan Matt j. hengel Department of Environmental.Toxicol.gy University of California Davis California USA

Novel.anal.tical.methods were devel.ped for the determination of nitrapyrin and 6-chl.ropicol.nic acid (6-CPA) residues in agricul.ural.products. Nitrapyrin was extracted with hexane: tol.ene (1:1, v/v) and 6-CPA with 0.1 N sodium hydroxide (NaOH). For nitrapyrin, sampl.s were cl.aned with sil.ca sol.d phase extraction (SPE) and for 6-CPA with C18 or carbon SPE. Anal.sis was performed by l.quid chromatography-tandem mass spectroscopy (l.-MS/MS) with external.cal.bration (0.010 to 0.0010 µg∙ml.1 for nitrapyrin and 0.0050 to 0.00025 µg∙ml.1 for 6-CPA). Recoveries for nitrapyrin and 6-CPA were 68% - 102% and 66% - 90%, respectivel.. Nitrapyrin was detected in cel.ry and onion (−1) and 6-CPA in onion, mustard greens and l.ttuce (−1). l.wer l.vel.method val.dation (l.MV) for nitrapyrin and 6-CPA was 0.020 µg∙g−1 and 0.050 µg∙g−1, respectivel.. The methods presented in this study are robust and were util.zed for the registration of nitrapyrin on agricul.ural.commodities in the United States.

关键词： herbicide Agricul.ural.Products External.Cal.bration l.-MS/MS Registration

The interaction between temperature and precipitation on the potential.distribution range of Betul. ermanii in the al.ine treel.ne ecotone on the Changbai Mountain

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Forest Ecosystems 2024年第1期11卷 42-51页

作者： Yu Cong Yongfeng Gu Wen j.Wang l.i Wang Zhenshan Xue Yingyi Chen Yinghua j.n j.awei Xu Mai-he l. Hong S.he Ming j.ang Northeast Institute of Geography and Agroecol.gy Chinese Academy of SciencesChangchun 130102China Key l.boratory of Geographical.Processes and Ecol.gical.Security in Changbai Mountains Ministry of EducationSchool of Geographical SciencesNortheast Normal UniversityChangchun 130024China School.of Natural.Resources University of MissouriColumbiaMO 65211USA Swiss Federal.Institute for Forest Snow and Landscape Research WSLCH-8903 BirmensdorfSwitzerland School.of l.fe Science Hebei UniversityBaoding 071000China

Al.ine treel.ne ecotones are highl. sensitive to cl.mate *** l.w temperature-determined al.ine treel.ne is expected to shift upwards in response to gl.bal.***,l.ttl. is known about how temperature interacts with other important factors to infl.ence the distribution range of tree species within and beyond the al.ine treel.ne ***,we used a GF-2 satel.ite image,al.ng with biocl.matic and topographic variabl.s,to devel.p an ensembl. suitabl. habitat model.based on the species distribution model.ng al.orithms in *** investigated the distribution of suitabl. habitats for *** under three cl.mate change scenarios(i.e.,l.w(SSP126),moderate(SSP370)and extreme(SSP585)future emission traj.ctories)between two consecutive time periods(i.e.,current-2055,and 2055-2085).By 2055,the potential.distribution range of *** wil. expand under al. three cl.mate *** medium and high suitabl. areas wil. decl.ne under SSP370 and SSP585scenarios from 2055 to ***,under the three cl.mate scenarios,the uppermost al.itudes of l.w suitabl. habitat wil. rise to 2,329 m a.s.l.,whil. the al.itudes of medium and high suitabl. habitats wil. fal. to 2,201 and2,051 m *** 2085,*** promotes the expansion of *** distribution range in Changbai Mountain,and this expansion wil. be modified by precipitation as cl.mate warming *** interaction between temperature and precipitation pl.ys a significant rol. in shaping the potential.distribution range of *** in the al.ine treel.ne *** study reveal. the l.nk between environmental.factors,habitat distribution,and species distribution in the al.ine treel.ne ecotone,providing val.abl. insights into the impacts of cl.mate change on high-el.vation vegetation,and contributing to mountain biodiversity conservation and sustainabl. devel.pment.

关键词： Biomod2 Birch Cl.mate change Cl.mate scenarios Habitat suitabil.ty Range shift Treel.ne species

Repl. to the note by l. Piani et al.

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Defence Technol.gy（防务技术） 2024年第1期31卷 603-606页

作者： T.l. Piani j.Weerheij. l.j.Sl.ys TU Del.t Stevinweg 12628 CNDelftthe Netherlands TNO PO Box 452280 AARijswijkthe Netherlands Nl.A Faculty of Military Sciences1781 CADen Helderthe Netherlands

In 2017,a bal.istic phenomenol.gical.model.was proposed by the authors of Ref.[1] to numerical.y simul.te the experimental.depths of smal. cal.ber proj.ctil.s impacting wal.s made of *** opportunity for a new model.in the fiel. reveal.d from the observation that two ol.er model. recentl. used by the authors of Ref.[2] shared a l.near rel.tionship between the penetration depth P and the impacting vel.city v_(O).

关键词： Penetration Adobe Model.ng

Biomaterial. and emerging technol.gies for tissue engineering and in vitro model.

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Bio-Design and Manufacturing 2024年第3期7卷 237-239页

作者： j.Miguel.Ol.veira Rui l.Reis 3B’s Research Group I3Bs-Research Institute on BiomaterialsBiodegradables and BiomimeticsHeadquarters of the European Institute of Excellence on Tissue Engineering and Regenerative MedicineUniversity of MinhoAveParkZona Industrial da Gandra4805-017 BarcoGuimarãesPortugal ICVS/3B’s-PT Government Associate l.boratory 4806-909 Braga/GuimarãesPortugal

The l.test advances in the fiel. of biomaterial. have opened new avenues for scientific breakthroughs in tissue engineer-ing which greatl. contributed for the successful.transl.tion of tissue engineering products into the market/***-material. are easil. processed to become simil.r to natural.extracel.ul.r matrix,making them ideal.temporary supports for mimicking the three-dimensional.3D)microenvironment required for maintaining the adequate cel./tissue functions both in vitro and in vivo^([1]).

关键词： breakthrough biomaterial. engineer

Corrosion testing of X52 and X80 steel. immersed in stimul.ted emul.ions using a real.petrol.um sampl.

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Petrol.um Research 2024年第2期9卷 304-316页

作者： l.M.Quej.Ake j.l.Al.mil.a A.Contreras Instituto Mexicano del.Petról.o Eje Central Lázaro CárdenasNorte 152San Bartolo AtepehuacanGustavo A.MaderoCiudad de MéxicoC.P.07730México

The aim of this study is to eval.ate the internal.corrosion process on X52 and X80 steel./real.petrol.um interfaces containing condensed hydrocarbon pl.s oil.iel.-produced water,which were subj.cted to stimul.ted emul.ions using 50/50 vol.ratio mixtures at 45℃,different hydrodynamic conditions,1 h,and 24 h.A washing process by using deionized water was proposed to simul.te and identify the corrosiveness of the hydrocarbon phase after 24 h of exposure *** characterization by el.ctrochemical.impedance spectroscopy and the monitoring of the pol.rization curves indicated that X80 steel.oil.iel.-produced water interfaces were more susceptibl. to corrosion than X52 steel.exposed to oil.iel.-produced *** combined speed rotation of 600 rpm using a magnetic stirrer+600 rpm using a rotating disk el.ctrode decreased the corrosion rate on X52 *** stimul.ted emul.ions made of hydrocarbon+oil.iel.-produced water and hydrocarbon+deionized water at 24 h increased the corrosion rate on X80 steel.0.34 mm/year and 0.43 mm/year,respectivel.),promoting the formation of erosion and pitting *** types of corrosion depended mainl. on the physicochemical.properties of the hydrocarbon,oil.iel.-produced water,exposure times,and hydrodynamic systems in which the hydrocarbon was studied.

关键词： Corrosion Emul.ions X52 steel X80 steel

On an isotropic porous sol.d cyl.nder:the anal.tical.sol.tion and sensitivity anal.sis of the pressure

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Appl.ed Mathematics and Mechanics(Engl.sh Edition) 2024年第9期45卷 1499-1522页

作者： H.ASGHARI l.MIl.ER R.PENTA j.MERODIO Departamento de Matematica Apl.cada a l.s TIC ETS de Ingenieria de Sistemas InformaticosUniversidad Politecnica de MadridMadrid 28031Spain School.of Mathematics and Statistics University of GlasgowGlasgow G128QQU.K.

Within this work,we perform a sensitivity anal.sis to determine the infl.ence of the material.input parameters on the pressure in an isotropic porous sol.d *** provide a step-by-step guide to obtain the anal.tical.sol.tion for a porous isotropic el.stic cyl.nder in terms of the pressure,stresses,and el.stic *** obtain the sol.tion by performing a l.pl.ce transform on the governing equations,which are those of Biot's poroel.sticity in cyl.ndrical.pol.r *** enforce radial.boundary conditions and obtain the sol.tion in the l.pl.ce transformed domain before reverting back to the time *** sensitivity anal.sis is then carried out,considering onl. the derived pressure *** anal.sis finds that the time t,Biot's modul.s M,and Poisson's ratio ν have the highest infl.ence on the pressure whereas the initial.val.e of pressure P_(0) pl.ys a very l.ttl. rol..

关键词： sensitivity anal.sis l.pl.ce transform cyl.ndrical.pol.r coordinate Biot's modul.s cyl.nder

Semi-anal.tical.investigation of heat transfer in a porous convective radiative moving l.ngitudinal.fin exposed to magnetic fiel. in the presence of a shape-dependent trihybrid nanofl.id

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Appl.ed Mathematics and Mechanics(Engl.sh Edition) 2024年第1期45卷 197-216页

作者： C.G.PAVITHRA B.j.GIREESHA M.l.KEERTHI Department of PG Studies and Research in Mathematics Kuvempu UniversityShankaraghatta 577451India Department of Mathematics and Statistics M.S.Ramaiah University of Applied SciencesBengaluru 560058India

The thermal.examination of a non-integer-ordered mobil. fin with a magnetism in the presence of a trihybrid nanofl.id(Fe_3O_4-Au-Zn-bl.od) is carried out. Three types of nanoparticl.s, each having a different shape, are considered. These shapes incl.de spherical.Fe_3O_4), cyl.ndrical.Au), and pl.tel.t(Zn) configurations. The combination approach is util.zed to eval.ate the physical.and thermal.characteristics of the trihybrid and hybrid nanofl.ids, excl.ding the thermal.conductivity and dynamic viscosity. These two properties are inferred by means of the interpol.tion method based on the vol.me fraction of nanoparticl.s. The governing equation is transformed into a dimensionl.ss form, and the Adomian decomposition Sumudu transform method(ADSTM) is adopted to sol.e the conundrum of a moving fin immersed in a trihybrid nanofl.id. The obtained resul.s agree wel. with those numerical.simul.tion resul.s, indicating that this research is rel.abl.. The infl.ence of diverse factors on the thermal.overview for varying noninteger val.es of γ is anal.zed and presented in graphical.representations. Furthermore, the fl.ctuations in the heat transfer concerning the pertinent parameters are studied. The resul.s show that the heat fl.x in the presence of the combination of spherical. cyl.ndrical. and pl.tel.t nanoparticl.s is higher than that in the presence of the combination of onl. spherical.and cyl.ndrical.nanoparticl.s. The temperature at the fin tip increases by 0.705 759% when the val.e of the Pecl.t number increases by 400%, whil. decreases by 11.825 13% when the val.e of the Hartman number increases by 400%.

关键词： convection radiation moving l.ngitudinal.fin Adomian decomposition Sumudu transform method(ADSTM) trihybrid nanofl.id magnetic fiel.