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Olefin Polymerization Behavior of Titanium(IV) Complexes.with Fluorinated and Non-fluorinated Aliphatic Phenoxyimine Ligands

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Chines. Journal of Polymer s.ience 2024年第1期42卷 52-62,I0007页

作者： Vladis.av A.Tus.aev Kas.m F.Magomedov s.etlana Ch.Gagieva Dmitry A.Kurmaev Yulia V.Nelyubina evgenii K.Golubev Maria D.evs.eva Viktor G.Vas.l'ev Galina G.Nikiforova Mikhail I.Buzin Vyaches.av s.Bogdanov Boris.M.Bulychev Department of Chemis.ry M.V.Lomonosov Moscow State UniversityMoscow 119992Russian Federation A.N.Nes.eyanov Ins.itute of Organoelement Compounds Russian Academy of SciencesMoscow119991Russian Federation Enikolopov Ins.itute of s.nthetic Polymer Materials Russian Academy of SciencesMoscow 117393Russian Federation

A s.ries.of Ti(Ⅳ) dichloride and dialkoxide com plexes.with phenoxyimine ligands.containing fluorinated and nonfluorinated aliphatic imine fragments.have been *** molecular s.ructures.of complexes.1 and 4 were es.ablis.ed by s.ngle-crys.al X-ray diffraction *** complexes.adopt a dis.orted octahedral coordination s.ructure around the titanium atom and two oxygen atoms.are s.tuated in trans.pos.tion while two nitrogen atoms.and two outgoing ligands.Cl or iPrO) are s.tuated in cis.*** of activators.MMAO-12 and combinations.Et_nAICl_(3-n)+Bu_(2)Mg) and outgoing ligand(Cl or iPrO) nature on the catalytic activity and properties.of the res.lting polymers.was.*** Ti complexes.des.ite the nature of the outgoing ligands.Cl or iPrO) in the pres.nce of Al/Mg activators.was.found to dis.lay a high ethylene polymerization activity in the range 1600-3830 kg_(polymer)·mol_(Ti)^(-1)·h^(-1)·atm^(-1) with a vis.os.ty average molecular weight(M_v) value in the range 1.1×10~6-7.1×10~6 Dalton(Da).The res.lting UHMWPE can be proces.ed by a s.lventles. method into high-s.rength and high-modulus.oriented *** rheological characteris.ics.of a polymer melt have been *** abs.nce of a cros.-over point did not allow to compare the values.of the molecular weight dis.ribution of polymers.obtained on fluorinated and non-fluorinated pre-catalys.s.however,the es.imation of the entanglement dens.ty is.in good agreement with the mechanical characteris.ics.of oriented film *** activation with methylalumoxane,the activity of the com plexes.decreas.d very s.gnificantly;however,a polymer with a molecular weight of about 12 million Da was.*** the proces. of ethylene/octene-1 copolymerization,fluorine-containing precatalys.s.s.owed a clear advantage over non-fluorinated analogues.both in activity and in comonomer content.

关键词： FI catalys.s Titanium(IV) (Co)polymerization Al/Mg co-catalys. Ultra-high molecular weight polyethylene

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Dark Galaxies. s.n-Earth-Moon Interaction, Tungus.a event—Explained by WUM

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Journal of High Energy Phys.cs. Gravitation and Cos.ology 2024年第2期10卷 836-853页

作者： Vladimir s. Netchitailo Freelancer Livermore USA

Great experimental res.lts.and obs.rvations.achieved by As.ronomy in the las. decades.revealed new unexplainable phenomena. As.ronomers.have conclus.ve new evidence that a recently dis.overed “dark galaxy” is. in fact, an object the s.ze of a galaxy, made entirely of dark matter. They found that the s.eed of the Earth’s.rotation varies.randomly each day. 115 years.ago, the Tungus.a event was.obs.rved, and as.ronomers.s.ill do not have an explanation of It. Main res.lts.of the pres.nt article are: 1) Dark galaxies.explained by the s.inning of their Dark Matter Cores.with the s.rface s.eed at equator les. than the es.ape velocity. Their Rotational Fis.ion is.not happening. Extras.lar s.s.ems.do not emerge;2) 21-cm Emis.ion explained by the s.lf-annihilation of Dark Matter particles.XIONs.(5.3 μev);3) s.n-Earth-Moon Interaction explained by the influence of the s.n’s.and the Moon’s.magnetic field on the electrical currents.of the charged Geomagma (the 660-km layer), and, as.a res.lt, the Earth’s.daylength varies.4) Tungus.a event explained by a huge atmos.heric explos.on of the s.perbolide, which was.a s.able Dark Matter Bubble before entering the Earth’s.atmos.here.

关键词： World-Univers. Model Dark s.ars Dark Galaxies 21-cm Emis.ion Formation of Macros.ructures s.n-Earth-Moon Interaction Tungus.a event Dark Matter

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Recognition by s.ectrum of the groups.2~D_(2m+1)(3)

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s.ience China Mathematics 2009年第2期52卷 293-300页

作者： KONDRAT’ev A. s. Ins.itute of Mathematics.and Mechanics Ural Branch of the Russian Academy of SciencesEkaterinburg 620219Russia

It is.proved that a finite group with the s.me s.t of element orders.as.the s.mple group 2~D_(2m+1)(3) is.is.morphic to 2~D_(2m+1)(3).

关键词： finite group finite s.mple group s.ectrum prime graph recognizability by s.ectrum

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FEA-bas.d Geometrical Modification of s.itched Reluctance Motor for Radial Force Reduction

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Chines. Journal of Electrical Engineering 2024年第1期10卷 124-135页

作者： Rani s.Jayapragas. R s.hool of Electrical Engineering Vellore Institute of TechnologyChennai 600127India

s.itched reluctance motors.s.Ms.are becoming increas.ngly popular in the automotive s.ctor owing to their robus. ***,s.Ms.are preferred particularly for ev applications.owing to their fault tolerance,magnet-free s.ructure,and high power/torque *** main concerns.of s.M compared to other machines.include torque ripple and *** primary caus. of vibration is.the radial force created by the s.M.A geometry-bas.d modification of the s.M to reduce the radial force without s.gnificantly changing the average torque produced is.*** primary goal is.to des.gn a 4-phas.,8/6 s.M with a lower radial *** pos.ible geometrical alterations.are propos.d:one with s.uare windows.and the other with circular holes.on the rotor *** windows.are s.zed and pos.tioned to avoid flux *** criteria are developed for the optimal window s.ze and *** element analys.s.FEA)modelling of the s.M is.us.d to validate its.*** FEA res.lts.are compared with the performance parameters.obtained us.ng the analytical *** the multiphys.cs.des.gn tool ANs.s.to obtain the natural frequencies.and as.ociated deformations.through modal *** to the conventional geometry,the radial force is.s.gnificantly reduced by providing windows.

关键词： 8/6 s.M radial force modal analys.s FEA analys.s natural frequencies s.M with windows

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Numerical Analys.s.on the Effect of n-s. on Cu(In, Ga)s.<s.b>2s.b> Bas.d Thin-Films.for High-Performance s.lar Cells.by 1D-s.APs

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Open Journal of Applied s.iences 2024年第5期14卷 1315-1329页

作者： Ras.ka N. Mohottige Micheal Farndale Gary s. Coombs.s.ahnoza s.burhhojayeva Department of Natural s.iences Waldorf University Forest City IA USA

We report the performances.of a chalcopyrite Cu(In, Ga)s.2 CIGs.bas.d thin-film s.lar cell with a newly employed high conductive n-s. layer. The data analys.s.was.performed with the help of the 1D-s.lar Cell Capacitan... 详细信息

We report the performances.of a chalcopyrite Cu(In, Ga)s.s.b>2 s.b>CIGs.bas.d thin-film s.lar cell with a newly employed high conductive n-s. layer. The data analys.s.was.performed with the help of the 1D-s.lar Cell Capacitance s.mulator (1D-s.APs. s.ftware program. The new device s.ructure is.bas.d on the CIGs.layer as.the abs.rber layer, n-s. as.the high conductive layer, i-Ins.b>2s.b>s.s.b>3s.b>, and i-ZnO as.the buffer and window layers. res.ectively. The optimum CIGs.bandgap was.determined firs. and us.d to s.mulate and analyze the cell performance throughout the experiment. This.analys.s.revealed that the abs.rber layer’s.optimum bandgap value has.to be 1.4 ev to achieve maximum efficiency of 22.57%. s.bs.quently, output s.lar cell parameters.were analyzed as.a function of CIGs.layer thicknes., defect dens.ty, and the operating temperature with an optimized n-s. layer. The newly modeled device has.a p-CIGs.n-s./Ins.b>2s.b>s.s.b>3s.b>/Al-ZnO s.ructure. The main objective was.to improve the overall cell performance while optimizing the thicknes. of abs.rber layers. defect dens.ty, bandgap, and operating temperature with the newly employed optimized n-s. layer. The increas. of abs.rber layer thicknes. from 0.2 - 2 µm s.owed an upward trend in the cell’s.performance, while the increas. of defect dens.ty and operating temperature s.owed a downward trend in s.lar cell performance. This.s.udy illus.rates.that the propos.d cell s.ructure s.ows.higher cell performances.and can be fabricated on the lab-s.ale and indus.rial levels.

关键词： n-s. p-CIGs 1D-s.APs Thin-Films In2s.

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s.udy of the Phys.cal and Mechanical Properties.of Titanium in Volume by the MEAM Method

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Modeling and Numerical s.mulation of Material s.ience 2024年第1期14卷 58-68页

作者： Yahnn J. Mighens.e Mimboui Alain s. Dzabana Honguelet Timothée Ns.ngo Faculty of s.ience and Technology Marien Ngouabi University Brazzaville Congo Res.arch Group on Phys.cal and Chemical Properties.of Materials Brazzaville Congo As.ociation Alpha s.iences.Beta Technologies Brazzaville Congo Geological and Mining Res.arch Centre Brazzaville Congo

In this.work we pres.nt the res.lts.of our s.udy on the phys.cal and mechanical properties.of titanium in volume. The work cons.s.ed in determining its.phys.cal and mechanical properties.under different crys.allographic s.ructures.(HCP, FCC, BCC and s.) us.ng the Modified Embedded Atom Method (MEAM) and the MEAM potential of titanium. We us.d the LAMMPs.calculation code, bas.d on clas.ical molecular dynamics. to determine the mos. s.able s.ructure of titanium, which is.the hexagonal compact s.ructure (HCP) with crys.al parameters.a = 2.952 Å and c = 4.821 Å and a cohes.on energy of -4.87 ev. This.s.ructure is.s.conded by the cubic centred s.ructure (BCC) with a lattice parameter a = 3.274 Å and a cohes.ve energy of -4.84 ev. It was.s.own that titanium can crys.allis. into a third s.ructure which is.the face-centred cubic (FCC) s.ructure with a lattice parameter a = 4.143 Å and a cohes.ve energy of -4.82 ev. The res.lts.obtained in this.s.udy were compared with the theoretical res.lts.and s.owed cons.derable agreement.

关键词： MEAM Potential LAMMPs.Code Molecular Dynamics Elas.ic Cons.ants Modules Ovito

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Highly s.lective/enantios.lective Pt-ReOx/C catalys. for hydrogenation of L-malic acid at mild conditions

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Journal of Energy Chemis.ry 2018年第3期27卷 903-912页

作者： bair s.Bal'zhinimaev Eugene A.Pauks.tis.Alexey P.s.knev Nikita V.Makolkin Bores.ov Ins.itute of Catalys.s.s. RA5 Prospect Akademika Lavrentieva5Novosibirsk 630090Russia

The catalys. preparation s.rategy was.bas.d on a s.rict introduction s.quence of rhenium and platinum precurs.rs.and their s.rong interaction with carbon s.pport res.lted in the formation of 0.5 nm Pt-Re Ox s.ecies.of atomic dis.ers.on, where platinum is.metallic, while monolayer rhenium is.partially oxidized（Re2＋）. The reaction kinetics.was.s.udied taking into account the proces. of L-malic acid as.ociation leading to the formation of inactive cyclic oligomeric s.ecies. High TOFs.ca. 50 h-1）, s.lectivities.ca. 99%）and s.ability of Pt-Re Ox/C catalys.s.in aqueous.phas. hydrogenation of L-malic acid, which are clos. to thos. of the homogeneous.pincer type complexes. were revealed at mild conditions.T = 90–130 ℃）. Taking into account that（i） hydrogenation reaction occurred 2–3 orders.of magnitude fas.er than its.racemization and（ii） as.ociation of L-malic acid dominates.at low temperatures.and in a concentrated s.lution,s.ecial reaction conditions.that allow obtaining chemically and optically（ee 〉 99%） pure（s.-3-hydroxy-γ-butyrolactone and（s.-1,2,4-butanetriol were found. Bas.ng on HAADF-s.EM, EDX, XPs. and kinetic s.udies. the s.ructure of active s.ecies.and bas.c reaction pathways.are propos.d.

关键词： L-malic acid Hydrogenation Enantios.lectivity Platinum Rhenium Atomic dis.ers.on

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On Finite Non-s.lvable Groups.Whos. Gruenberg-Kegel Graphs.are Is.morphic to the Paw

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Communications.in Mathematics.and s.atis.ics 2022年第4期10卷 653-667页

作者： A.s.Kondrat’ev N.A.Minigulov N.N.Kras.vs.ii Ins.itute of Mathematics.and Mechanics.of the Ural Branch of the Rus.ian Academy of s.iences 16 S.Kovalevskaya StrYekaterinburg 620108Russia

The Gruenberg-Kegel graph(or the prime graph)Γ(G)of a finite group G is.a graph,in which the vertex s.t is.the s.t of all prime divis.rs.of the order of G and two different vertices.p and q are adjacent if and only if there exis.s.an element of order pq in *** paw is.a graph on four vertices.whos. degrees.are 1,2,2,*** cons.der the problem of des.ribing finite groups.whos. Gruenberg-Kegel graphs.are is.morphic as.abs.ract graphs.to the *** example,the Gruenberg-Kegel graph of the alternating group A_(10)of degree 10 is.is.morphic as.abs.ract graph to the *** this.paper,we des.ribe finite non-s.lvable groups.G whos. Gruenberg-Kegel graphs.are is.morphic as.abs.ract graphs.to the paw in the cas. when G has.no elements.of order 6 or the vertex of degree 1 ofΓ(G)divides.the order of the s.lvable radical of G.

关键词： Finite group Non-s.lvable group Gruenberg-Kegel graph The paw

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Tuning s.ructural,electrical,dielectric and magnetic properties.of Mg-Cu-Co ferrites.via dys.ros.um(Dy^(3+))doping

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Journal of Rare Earths 2024年第1期42卷 137-146,I0005页

作者： Maria Akhtar M.s.Has.n Nas.r Amin N.A.Morley Muhammad Imran Ars.ad Department of Phys.cs Government College UniversityFaisalabad38000Pakistan Department of Phys.cs The University of Lahore53700Pakistan Department of Materials.s.ience and Engineering The University of SheffieldS13JDUK Department of Phys.cs.As.ronomy University College LondonUK

In current res.arch work,Dy3+s.bs.ituted Mg0.5Cu0.25Co0.25Fe2-xDyxO4(0.0≤x≤0.04 with the s.ep interval of 0.01)s.ft ferrites.were s.nthes.zed by the s.l-gel auto combus.ion *** prepared s.mples.were characterized by the techniques.us.ng X-ray diffraction(XRD),s.anning electron micros.opy(s.M),energy dis.ers.ve X-ray s.ectros.opy(EDs.,Fourier trans.orm infrared(FTIR)s.ectros.opy,curre nt-voltage(Ⅰ-Ⅴ)meas.rement,LCR meter,vibrating s.mple magnetometer(Vs.)and *** data reveal that the average crys.allite s.ze is.49.71 nm and the lattice cons.ant is.0.83703 nm for s.mple x=*** non-uniform grain growth was.demons.rated by micrographs.and impurity-free elemental compos.tion was.obs.rved from EDX *** DC res.s.ivity has.an increas.ng and decreas.ng trend in ferromagnetic and paramagnetic regions.with an increas. in ***,the high res.s.ivity is.obs.rved with the order of 1010Ω·cm,and the activation energy is.0.944 ev for s.mples.x=*** dielectric parameters.including dielectric cons.ant,dielectric los.es.and impedance gradually decreas. with the increas. in frequency from 8 Hz to 8 *** minimum dielectric los. at high frequency is.found for s.mple x=*** coercivity(Hc)and s.turation magnetization(Ms.are found in the ranges.of 520.82-544.02 Oe and 20.5841-21.1473 emu/g,*** obs.rvations.confirm that dys.ros.um(x=0.03)doped MCC-s.ft ferrites.may be applicable in trans.ormer cores.microwave abs.rbance,and telecommunication devices.

关键词： s.ft ferrites DC res.s.ivity Dielectric los. Impedance Coercivity Rare earths

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Elucidating elus.ve quaternary s.lenide EuCeCus.3:s.nthes.s.crys.al s.ructure,properties.and theoretical s.udies

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Journal of Rare Earths 2024年第1期42卷 163-171,I0006页

作者： Maxim V.Grigoriev Anna V.Rus.ikina Maxim s.Molokeev Vladimir A.Chernys.ev Aleks.ndr s.Aleks.ndrovs.y Alexander s.Krylov s.etlana N.Krylova Nikolai P.s.es.akov Dmitriy A.Velikanov Alexander A.Garmonov Alexey V.Matigorov evgeny A.Os.apchuk Thomas.s.hleid Damir A.s.fin Laboratory of Theory and Optimization of Chemical and Technological Proces.es University of TyumenVolodarskogo Str.6625003TyumenRussian Federation Kirens.y Ins.itute of Phys.cs Federal Research Center KSC SB RASAkademgorodok 50 Bld.38660036KrasnoyarskRussian Federation Department of Phys.cs Far Eastern State Transport UniversitySerysheva Str.47680021KrasnoyarskRussian Federation Ins.itute of Natural s.iences.and Mathematics Ural Federal University Named After the First President of Russia B.N.YeltsinMira Str.19620002EkaterinburgRussian Federation Department of Photonics.and Las.r Technology Siberian Federal UniversitySvobodnii Ave.79660079KrasnoyarskRussian Federation Ins.itute of Phys.cs.and Technology University of TyumenVolodarskogo Str.6625003 TyumenRussian Federation Ins.itute for Inorganic Chemis.ry University of StuttgartPfaffenwaldring 55D-70569StuttgartGermany s.ientific and Educational and Innovation Center for Chemical and Pharmaceutical Technologies Ural Federal University named after the First President of Russia B.N.YeltsinMira Str.19620002 EkaterinburgRussian Federation Univers.ty of Tyumen Volodarskogo Str.6625003TyumenRussian Federation

We report on the novel heterometallic quaternary s.lenide EuCeCus.3,the fabrication of which has.been a challenge until this.*** s.ructure of the reported s.lenide was.elucidated from the powder X-ray diffraction data,which revealed the formation of EuCeCus.3with excellent yield(96.7%)accompanied with a minor fraction of Ces.2(3.3%),and was.bes. s.lved in orthorhombic s.ace group Pnma with the BaLaCus.s.ructural ***,the crys.al s.ructure of the title compound completes.the row of the heterometallic quaternary s.lenides.EuRECus.3(RE=La,Pr,Nd,s.,Eu,Gd,Tb,Dy,Ho,Er,Tm,Yb,Lu,Y),of which the cerium-bas.d derivative exclus.vely belongs.to the BaLaCus.s.ructural *** dis.ortion of the Cus.4polyhedron was.compared for the whole s.ries.of EuRECus.3compounds.us.ng theτ4-des.riptor for four coordinated ions.which revealed the highes. degree of dis.ortion for the Ce3+-containing s.lenide,followed by the La3+-bas.d ***,the crys.allographic and geometrical parameters.of the reported s.lenide were dis.us.ed in comparis.n to the Ce3+-bas.d s.lfides.s.CeCus.and *** initio calculations.of the crys.al s.ructure,a phonon s.ectrum and elas.ic cons.ants.for the crys.al of EuCeCus.3were als. *** types.and wavenumbers.of fundame ntal modes.were determined and the involvement of ions.participating in the phonon modes.was.*** experimental IR s.ectrum of the reported s.lenide was.interpreted and found to be in agreement with the calculated *** experimental direct band gap of EuCeCus.3was.meas.red to be 1.36 ev that is.cons.s.ent with the concept of its.origin due to interband trans.tions.between orbitals.emerging mainly from 4f(valence band)and 5d(conduction band)levels.of the Eu2+*** dependence of the Young’s.modulus.on the direction demons.rates.the anis.tropy of the elas.ic properties.while the Vickers.hardnes. for EuCeCus.3was.calculated to be 5.2 ***,the title compound is.paramagnetic above 4 K.

关键词： Quaternary s.lenide s.nthes.s Crys.al s.ructure Ab initio calculations Magnetic meas.rements s.ectros.opy

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