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

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Chinese Journal of Polymer Science 2024年第1期42卷 52-62,I0007页

作者： Vladislav A.Tuskaev Kasim F.Magomedov Svetlana Ch.Gagieva Dmitry A.Kurmaev Yulia V.Nelyubina evgenii K.Golubev Maria D.evseeva Viktor G.Vasil'ev Galina G.Nikiforova Mikhail I.Buzin Vyacheslav S.Bogdanov Boris M.Bulychev Department of Chemistry M.V.Lomonosov Moscow State UniversityMoscow 119992Russian Federation A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesMoscow119991Russian Federation enikolopov Institute of Synthetic Polymer Materials Russian Academy of SciencesMoscow 117393Russian Federation

A series of Ti(Ⅳ) dichloride and dialkoxide com plexes with phenoxyimine ligands containing fluorinated and nonfluorinated aliphatic imine fragments have been *** molecular structures of complexes 1 and 4 were established by single-crystal X-ray diffraction *** complexes adopt a distorted octahedral coordination structure around the titanium atom and two oxygen atoms are situated in trans position while two nitrogen atoms and two outgoing ligands(Cl or iPrO) are situated 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 resulting polymers was *** Ti complexes,despite the nature of the outgoing ligands(Cl or iPrO) in the presence of Al/Mg activators,was found to display a high ethylene polymerization activity in the range 1600-3830 kg_(polymer)·mol_(Ti)^(-1)·h^(-1)·atm^(-1) with a viscosity average molecular weight(M_v) value in the range 1.1×10~6-7.1×10~6 Dalton(Da).The resulting UHMWPe can be processed by a solventless method into high-strength and high-modulus oriented *** rheological characteristics of a polymer melt have been *** absence of a cross-over point did not allow to compare the values of the molecular weight distribution of polymers obtained on fluorinated and non-fluorinated pre-catalysts,however,the estimation of the entanglement density is in good agreement with the mechanical characteristics of oriented film *** activation with methylalumoxane,the activity of the com plexes decreased very significantly;however,a polymer with a molecular weight of about 12 million Da was *** the process of ethylene/octene-1 copolymerization,fluorine-containing precatalysts showed a clear advantage over non-fluorinated analogues both in activity and in comonomer content.

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

Non-thermal atmospheric-pressure positive pulsating corona discharge in degradation of textile dye Reactive Blue 19 enhanced by Bi_(2)O_(3) catalyst

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Plasma Science and Technology 2024年第2期26卷 104-113页

作者： Milica PeTROVIC Dragan RADIVOJevIC Sasa RANCev Nena VeLINOV Milos KOSTIC Danijela BOJIC Aleksandar BOJIC Department of Chemistry Faculty of Sciences and MathematicsUniversity of NisNis 18000Serbia Department of Physics Faculty of Sciences and MathematicsUniversity of NisNis 18000Serbia

In this work,monoclinic Bi_(2)O_(3) was applied for the first time,to the best of our knowledge,as a catalyst in the process of dye degradation by a non-thermal atmospheric-pressure positive pulsating corona *** research focused on the interaction of the plasma-generated species and the catalyst,as well as the role of the catalyst in the degradation *** decomposition of the anthraquinone reactive dye Reactive Blue 19(RB 19) was performed in a selfmade reactor ***_(2)O_(3) was prepared by electrodeposition followed by thermal treatment,and characterized by x-ray diffraction,scanning electron microscopy and energy-dispersive xray *** was observed that the catalyst promoted decomposition of plasma-generated H_(2)O_(2) into ·OH radicals,the principal dye-degrading reagent,which further attacked the dye *** catalyst improved the decolorization rate by 2.5 times,the energy yield by 93.4%and total organic carbon removal by 7.1%.excitation of the catalyst mostly occurred through strikes by plasma-generated reactive ions and radical species from the air,accelerated by the electric field,as well as by fast electrons with an energy of up to 15 ev generated by the streamers reaching the liquid *** strikes transferred the energy to the catalyst and created the electrons and holes,which further reacted with H_(2)O_(2) and water,producing ·OH *** was indentified as the primary role of the catalyst in this *** reactions followed pseudo first-order *** of H_(2)O_(2) and the dye degradation rate increased with increase in the input *** optimal catalyst dose was 500 mg·dm^(-3).The decolorization rate was a little lower in river water compared with that in deionized water due to the side reactions of ·OH radicals with organic matter and inorganic ions dissolved in the river water.

关键词： corona RB 19 Bi_(2)O_(3) catalyst degradation

Flat-footed Females and Missing Males:A New Genus and Species of Pleciofungivoridae(Diptera:Bibionomorpha)Represents the First Record of the Family from Mid-Cretaceous Kachin Amber

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Acta Geologica Sinica(english edition) 2024年第3期98卷 541-547页

作者： ZHANG Qingqing Wiesław KRZeMINSKI Jan SevCIK Vladimir BLAGODeROV Agnieszka SOSZYNSKA Kornelia SKIBINSKA Yunnan Key Laboratory for Palaeobiology Institute of PalaeontologyYunnan UniversityKunming 650500China MeC International Joint Laboratory for Palaeobiology and Palaeoenvironment Yunnan UniversityKunming 650500China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of SciencesNanjing 210008China Institute of Systematics and evolution of Animals Polish Academy of Sciences52551 KrakówPoland University of Ostrava Faculty of ScienceDepartment of Biology and EcologyChittussiho 10CZ-71000 OstravaCzech Republic National Museums Scotland EdinburghUK Natural History Museum LondonUK University of Lodz Faculty of Biology and Environmental ProtectionDepartment of Invertebrate Zoology and HydrobiologyBanacha 12/1690-237ŁódźPoland

A new genus and species,Cretopleciofungivora simpsoni *** ***.,from the extinct family Pleciofungivoridae(Diptera:Bibionomorpha),is discovered in mid-Cretaceous Kachin ***,this family was known only from imprints in sedimentary rocks of the Jurassic and the Lower *** of a representative of Pleciofungivoridae in Kachin amber confirms the presence of the family in the Upper *** new species has a unique structure of fore tarsus,with lobed and extended tarsal segments Ⅱ to Ⅳ,a feature hitherto known only in a few species of extant *** not particularly rare,the new species is currently known only from female *** reasons for this phenomenon,very unusual in Sciaroidea,are briefly discussed,including parthenogenesis as a potentially plausible hypothesis.

关键词： fungus gnats Sciaroidea Upper Cretaceous Burmese amber swollen tarsomeres

On Finite Non-Solvable Groups Whose Gruenberg-Kegel Graphs are Isomorphic to the Paw

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Communications in Mathematics and Statistics 2022年第4期10卷 653-667页

作者： A.S.Kondrat’ev N.A.Minigulov N.N.Krasovskii Institute of Mathematics and Mechanics of the Ural Branch of the Russian Academy of Sciences 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 set is the set of all prime divisors of the order of G and two different vertices p and q are adjacent if and only if there exists an element of order pq in *** paw is a graph on four vertices whose degrees are 1,2,2,*** consider the problem of describing finite groups whose Gruenberg-Kegel graphs are isomorphic as abstract graphs to the *** example,the Gruenberg-Kegel graph of the alternating group A_(10)of degree 10 is isomorphic as abstract graph to the *** this paper,we describe finite non-solvable groups G whose Gruenberg-Kegel graphs are isomorphic as abstract graphs to the paw in the case when G has no elements of order 6 or the vertex of degree 1 ofΓ(G)divides the order of the solvable radical of G.

关键词： Finite group Non-solvable group Gruenberg-Kegel graph The paw

Molecular Dynamics, Diffusion Coefficients and Activation energy of the electrolyte (Anode) in Lithium (Li and Li⁺), Sodium (Na and Na⁺) and Potassium (K and K⁺)

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Modeling and Numerical Simulation of Material Science 2024年第1期14卷 39-57页

作者： Alain Second Dzabana Honguelet Timothée Nsongo Bitho Rodongo earvin Loumbandzila Faculty of Science and Technology Marien Ngouabi University Brazzaville Congo Research Group on The Physical and Chemical Properties of Materials Brazzaville Congo Association Alpha Sciences Beta Technologies Brazzaville Congo Centre for Geological and Mining Research Brazzaville Congo

This work is a simulation modelling with the LAMMPS calculation code of an electrode based on alkali metals (lithium, sodium and potassium) using the MeAM potential. For different multiplicities, two models were studied;with and without gap. In this work, we present the structural, physical and chemical properties of the lithium, sodium and potassium electrodes. For the structural properties, the cohesive energy and the mesh parameters were calculated, revealing that, whatever the chemical element selected, the compact hexagonal hcp structure is the most stable, followed by the face-centred cubic CFC structure, and finally the BCC structure. The most stable structure is lithium, with a cohesion energy of -6570 ev, and the lowest bcc-hcp transition energy of -0.553 ev/atom, followed by sodium. For physical properties, kinetic and potential energies were calculated for each of the sectioned chemical elements, with lithium achieving the highest value. Finally, for the chemical properties, we studied the diffusion coefficient and the activation energy. Only potassium followed an opposite order to the other two, with the quantities with lacunae being greater than those without lacunae, whatever the multiplicity. The order of magnitude of the diffusion coefficients is given by the relationship DLi > DNa > Dk for the multiplicity 6*6*6, while for the activation energy the order is reversed.

关键词： Molecular Dynamics Diffusion Coefficients Activation energy Lithium Alkali Metals MeAM Potential

Hole-doping induced ferromagnetism in 2D materials

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npj Computational Materials 2022年第1期8卷 2180-2189页

作者： Ruishen Meng Lino da Costa Pereira Jean-Pierre Locquet Valeri Afanas’ev Geoffrey Pourtois Michel Houssa Department of Physics and Astronomy KU LeuvenCelestijnenlaan 200DLeuvenB-3001Belgium imec Kapeldreef 75B-3001LeuvenBelgium

Two-dimensional(2D)ferromagnetic materials are considered as promising candidates for the future generations of spintronic ***,2D materials with intrinsic ferromagnetism are ***,high-throughput first-principles simulations are performed to screen 2D materials that present a non-magnetic to a ferromagnetic transition upon hole doping.A global evolutionary search is subsequently performed to identify alternative possible atomic structures of the eligible candidates,and 122 materials exhibiting a hole-doping induced ferromagnetism are *** energetic and dynamic stability,as well as magnetic properties under hole doping are investigated *** of these 2D materials are metal halides,followed by chalcogenides,oxides,and nitrides,some of them having predicted Curie temperatures above 300 *** exchange interactions responsible for the ferromagnetic order are also *** work not only provides theoretical insights into hole-doped 2D ferromagnetic materials,but also enriches the family of 2D magnetic materials for possible spintronic applications.

关键词： ferromagnetic doping materials

Study of the Physical and Mechanical Properties of Titanium in Volume by the MeAM Method

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Modeling and Numerical Simulation of Material Science 2024年第1期14卷 58-68页

作者： Yahnn J. Mighensle Mimboui Alain S. Dzabana Honguelet Timothée Nsongo Faculty of Science and Technology Marien Ngouabi University Brazzaville Congo Research Group on Physical and Chemical Properties of Materials Brazzaville Congo Association Alpha Sciences Beta Technologies Brazzaville Congo Geological and Mining Research Centre Brazzaville Congo

In this work we present the results of our study on the physical and mechanical properties of titanium in volume. The work consisted in determining its physical and mechanical properties under different crystallographic structures (HCP, FCC, BCC and SC) using the Modified embedded Atom Method (MeAM) and the MeAM potential of titanium. We used the LAMMPS calculation code, based on classical molecular dynamics, to determine the most stable structure of titanium, which is the hexagonal compact structure (HCP) with crystal parameters a = 2.952 Å and c = 4.821 Å and a cohesion energy of -4.87 ev. This structure is seconded by the cubic centred structure (BCC) with a lattice parameter a = 3.274 Å and a cohesive energy of -4.84 ev. It was shown that titanium can crystallise into a third structure which is the face-centred cubic (FCC) structure with a lattice parameter a = 4.143 Å and a cohesive energy of -4.82 ev. The results obtained in this study were compared with the theoretical results and showed considerable agreement.

关键词： MeAM Potential LAMMPS Code Molecular Dynamics elastic Constants Modules Ovito

Finite Groups Isospectral to Simple Groups

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Communications in Mathematics and Statistics 2023年第2期11卷 169-194页

作者： Maria A.Grechkoseeva Victor D.Mazurov Wujie Shi Andrey V.Vasil’ev Nanying Yang Sobolev Institute of Mathematics Koptyuga 4NovosibirskRussia 630090 Department of Mathematics Chongqing University of Arts and SciencesChongqing 402160People’s Republic of China School of Mathematics Suzhou UniversitySuzhou 215006People’s Republic of China School of Science Hainan UniversityHaikou 570228HainanPeople’s Republic of China School of Science Jiangnan UniversityWuxi 214122People’s Republic of China

The spectrum of a finite group is the set of element orders of this *** main goal of this paper is to survey results concerning recognition of finite simple groups by spectrum,in particular,to list all finite simple g... 详细信息

关键词： Finite group Simple group element order Spectrum Recognition by spectrum

Fatal bleeding due to an aorto-esophageal fistula: A case report and literature review

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World Journal of Clinical Cases 2022年第31期10卷 11493-11499页

作者： Davorin Ćeranić Sara Nikolić Jernej Lučev Aleš Slanič Tatjana Bujas Andreja Ocepek Pavel Skok Department of Gastroenterology Internal Medicine ClinicUniversity Medical Centre MariborMaribor 2000Slovenia Department of Radiology University Medical Centre MariborMaribor 2000Slovenia Department of Pathology University Medical Centre MariborMaribor 2000Slovenia

BACKGROUND Aorto-esophageal fistula is an extremely rare cause of acute upper gastrointestinal bleeding(UGIB).CASe SUMMARY We present a case of an 80-year-old woman with esophageal cancer who was admitted to our department with hemorrhagic shock due to *** the diagnostic procedure,emergency computed tomography angiography was performed and confirmed aorto-esophageal *** radiologists inserted a stent graft into the aorta,successfully closing the ***,the patient later died of heart failure following irreversible hemorrhagic *** confirmed the aorto-esophageal fistula,which formed 1 cm below the distal edge of the stent previously inserted into the esophagus for a malignant *** There are very rare causes of *** clinical decisions are made during the diagnostic workup of these patients,we must be aware of the limitations of various therapeutic options,even the most contemporary.

关键词： Aorto-esophageal fistula Upper gastrointestinal bleeding Interventional radiology Stent graft Case report