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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

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Catalytic co-combustion of biomass and brown coal in a fluidized bed:Economic and environmental benefits

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Journal of Environmental sciences 2024年第6期140卷 24-36页

作者： Yury v.Dubinin Nikolay A.Yazykov Petr M.Yeletsky Roman B.Tabakaev Aleksandra I.Belyanovskaya vadim A.Yakovlev Federal Research Center Boreskov Institute of Catalysis sB ras Lavrentiev Ave.5Novosibirsk630090Russia University of Tyumen Volodarskogo str.6Tyumen625003Russia

The work is devoted to the study of combustion of brown coal,pine sawdust,and their mixtures in a fluidized bed of catalyst at 600-750℃.It is shown that an increase in the content of sawdust in a mixture with brown coal leads to an increase in the burnout degree of solid fuel from 94.4%to 99.9%,while the emission of greenhouse gases in the form of CO_(2)CO and NOxis reduced(CO_(2)from the biomass is not included in the balance).The high content of alkaline earth metal oxides(CaO and MgO)in the mineral part of brown coal,sawdust,and their mixtures eliminates the emission of sulfur oxides and the slagging of heat-exchange surfaces during the combustion in a fluidized bed of *** optimal temperature,when the highest burnout degree of the above fuels is achieved in the combustion is 750℃.It is also shown that the increase in temperature and the content of sawdust in the composition of the fuel mixtures has a positive effect on the economic and environmental process indicators.

关键词： Co-combustion Fluidized catalyst bed Biomass Coal Economic effect Environmental impact

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subaxial cervical spine injury classification system: is it most appropriate for classifying cervical injury?

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Neural Regeneration Research 2015年第9期10卷 1416-1417页

作者： Rafael Martínez-Pérez Francisco Fuentes víctor s.Alemany Division of Neurosurgery Department of Clinical Neurological Sciences University of Western Ontario Department of Neurology Hospital Rafael Méndez school of Medicine Universidad Complutense

The cervical spine injury represents a potential devastating disease with 6% associated in-hospital mortality （lain et al., 2015）. Neurological deterioration ranging from complete spinal cord injury （sCI） to incomplete sCI or single radiculopathy are potential consequences of the blunt trauma over this region. The subaxial cervical spine accounts the vast majority of cervical injuries, making up two thirds of all cervical fractures （Alday, 1996）. Few classifications （Holdsworth, 1970; White et al., 1975; Mien et al., 1982; Denis, 1984; vaccaro et al., 2007） have been proposed to describe injuries of the cervical spine for several reasons. First, to delineate the best treatment in each case; second, to determinate an accurate neurological prognosis, and third, to establish a standard way to communicate and describe specific characteristics of cervical injuries patterns. Classical systems are primarily descriptive and no single system has gained widespread use, largely because of restrictions in clinical relevance and its complexity.

关键词： is it most appropriate for classifying cervical injury sLIC subaxial cervical spine injury classification system

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Interaction of edge dislocations with voids in tungsten

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Tungsten 2024年第3期6卷 633-646页

作者： Arseny Kazakov Rita I.Babicheva Aleksandr Zinovev Dmitry Terentyev Kun Zhou Elena A.Korznikova sergey v.Dmitriev Research Laboratory for Metals and Alloys under Extreme Impacts Ufa University of Science and Technology Institute for Metals superplasticity Problems of ras school of Mechanical and Aerospace Engineering Nanyang Technological University Institute for Nuclear Energy Technology Belgian Nuclear Research Center Technological Machines and Equipment Department Ufa State Petroleum Technological University Institute of Mechanical science Problems of ras Institute of Molecule and Crystal Physics UFRC of Russian Academy of Sciences

Tungsten is widely used as a material capable of withstanding extreme operating conditions and is one of the candidates for use in fusion and Generation Ⅳ fission *** modelling implemented to solve various material science problems is an indispensable approach for improving material *** work analyzes the interaction of an edge dislocation with a void in single-crystal tungsten with the help of molecular dynamics *** different approaches for studying the dynamics of dislocations in tungsten that differ in boundary conditions are *** interactions of the dislocation and void at different temperatures are investigated,and based on the obtained stress-strain curves,the dislocation obstacle strength for voids having various diameters is *** is shown that when applied to a crystal with small voids,the model with the fixed boundary conditions returns incorrect ***,the influence of the cell size for the model with periodic boundary conditions is analyzed,and the case of a non-central interaction of a dislocation with a void is *** obtained results improve our understanding of the mechanical response of irradiated materials.

关键词： Tungsten Molecular dynamics method Dislocations voids Boundary conditions

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Phase composition,conductivity,and sensor properties of cerium-doped indium oxide

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Nano Materials science 2024年第2期6卷 193-200页

作者： M.I.Ikim G.N.Gerasimov v.F.Gromov O.J.Ilegbusi L.I.Trakhtenberg N.N.semenov Federal Research Center for Chemical Physics of ras MoscowRussia University of Central Florida OrlandoFLUSA Moscow Institute of Physics and Technology(state University) DolgoprudnyMoscow RegionRussia Lomonosov Moscow state University MoscowRussia

The hydrothermal synthesis of In_(2)O_(3)and CeO_(2)–In_(2)O_(3)is investigated as well as the properties of sensor layers based on these *** the synthesis of In_(2)O_(3),intermediate products In(OH)_(3)and InOOH are formed,which are the precursors of stable cubic(c-In_(2)O_(3))and metastable rhombohedral(rh-In_(2)O_(3))phases,respectively.A transition from c-In_(2)O_(3)to rh-In_(2)O_(3)is observed with the addition of CeO_(2).The introduction of cerium into rh-In_(2)O_(3)results in a decrease in the sensor response to hydrogen,while it increases in composites based on c-In_(2)O_(3).The data on the sensor activity of the composites correlate with XPs results in which CeO_(2)causes a decrease in the concentrations of chemisorbed oxygen and oxygen vacancies in rh-In_(2)O_(3).The reverse situation is observed in composites based on c-In_(2)O_(3).Compared to In_(2)O_(3)and CeO_(2)–In_(2)O_(3)obtained by other methods,the synthesized composites demonstrate maximum response to H_(2)at low temperatures by 70–100℃,and have short response time(0.2–0.5 s),short recovery time(6–7 s),and long-term stability.A model is proposed for the dependence of sensitivity on the direction of electron transfer between In_(2)O_(3)and CeO_(2).

关键词： Cerium oxide Indium oxide Nanocomposite Hydrothermal method Cubic phase Rhombohedral phase sensor response Conductivity Hydrogen Response/recovery time

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Metabolic complications in liver transplant recipients

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World Journal of Gastroenterology 2016年第28期22卷 6416-6423页

作者： Miguel jim.nez-Pérez Rocío González-Grande Edith Omonte Guzmán víctor Amo Trillo Juan Miguel Rodrigo López UGC de Aparato Digestivo Unidad de Hepatología-Trasplante Hepático Hospital Universitario Regional de Málaga

The metabolic syndrome(Ms), which includes obesity,dyslipidaemia, hypertension and hyperglycaemia according to the most widely accepted definitions now used, is one of the most common post-transplant complications, with a prevalence of 44%-58%. The Ms, together with the immunosuppression, is considered the main risk factor for the development of cardiovascular disease(CvD) in transplant recipients, which in turn accounts for 19%-42% of all deaths unrelated to the graft. The presence of Ms represents a relative risk for the development of CvD and death of 1.78. On the other hand, non-alcoholic fatty liver disease(NAFLD), considered as the manifestation of the Ms in the liver, is now the second leading reason for liver transplantation in the United states after hepatitis C and alcohol. NAFLD has a high rate of recurrence in the liver graft and a direct relation with the worsening of other metabolic disorders, such as insulin resistance or diabetes mellitus. Consequently, it is vitally important to identify and treat as soon as possible such modifiable factors as hypertension, overweight, hyperlipidaemia or diabetes in transplanted patients to thus minimise the impact on patient survival. Additionally, steroid-free regimens are favoured, with minimal immunosuppression to limit the possible effects on the development of the Ms.

关键词： Metabolic syndrome Liver transplantation Immunosuppressions Risk factors Non-alcoholic fatty liver disease

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sintering study of Ti6Al4v powders with different particle sizes and their mechanical properties

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International Journal of Minerals,Metallurgy and Materials 2018年第12期25卷 1389-1401页

作者： JoséLuis Cabezas-villa JoséLemus-Ruiz Didier Bouvard Omar jim.nez Héctor Javier vergara-Hernández Luis Olmos University Michoacana of san Nicolás of Hidalgo IIMMMorelia 58060México University Grenoble Alpes CNRSSIMaPGrenoble 38000France University of Guadalajara Departamento de Ingeniería de ProyectosZapopan 45100México National Technological Institute of Mexico I.T.MoreliaMorelia 58120México University Michoacana of san Nicolás of Hidalgo INICITMorelia 58060México

Ti6Al4v powders with three different particle size distributions(0–20, 20–45, and 45–75 μm) were used to evaluate the effect of the particle size distribution on the solid-state sintering and their mechanical properties. The sintering kinetics was determined by dilatometry at temperatures from 900 to 1260°C. The mechanical properties of the sintered samples were evaluated by microhardness and compression tests. The sintering kinetics indicated that the predominant mechanism depends on the relative density irrespective of the particle size used. The mechanical properties of the sintered samples are adversely affected by increasing pore volume fraction. The elastic Young's modulus and yield stress follow a power law function of the relative density. The fracture behavior after compression is linked to the neck size developed during sintering, exhibiting two different mechanisms of failure: interparticle neck breaking and intergranular cracking in samples with relative densities below and above of 90%, respectively. The main conclusion is that relative density is responsible for the kinetics, mechanical properties, and failure behavior of Ti6 Al4 v powders.

关键词： Ti6Al4v powders dilatometry microhardness sintering kinetics compression failure behavior

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Gene therapy: light is finally in the tunnel

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Protein & Cell 2011年第12期2卷 973-989页

作者： Huibi Cao Robert s.Molday jim Hu Programme in Physiology and Experimental Medicine Hospital for Sick ChildrenDepartments of Laboratory Medicine and Pathobiologyand PaediatricsUniversity of TorontoTorontoOntario M5G1X8Canada Department of Biochemistry and Molecular Biology 2350 Health Sciences MallUniversity of British ColumbiaVancouverB.C.V6T 1Z3Canada

After two decades of ups and downs,gene therapy has recently achieved a milestone in treating patients with Leber’s congenital amaurosis(LCA).LCA is a group of inherited blinding diseases with retinal degeneration and severe vision loss in early *** in several genes,including RPE65,cause the *** adenoassociated virus as a vector,three independent teams of investigators have recently shown that RPE65 can be delivered to retinal pigment epithelial cells of LCA patients by subretinal injections resulting in clinical benefits without side ***,considering the whole field of gene therapy,there are still major obstacles to clinical applications for other *** obstacles include innate and immune barriers to vector delivery,toxicity of vectors and the lack of sustained therapeutic gene ***,new strategies are needed to overcome these hurdles for achieving safe and effective gene *** this article,we shall review the major advancements over the past two decades and,using lung gene therapy as an example,discuss the current obstacles and possible solutions to provide a roadmap for future gene therapy research.

关键词： gene therapy transgenes viral vector non-viral vector helper-dependent adenoviral vector adenoassociated virus lentivirus cystic fibrosis transmembrane conductance regulator(CFTR) host immune responses

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Ophiolite hosted chromitite formed by supra-subduction zone peridotite–plume interaction

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Geoscience Frontiers 2020年第6期11卷 2083-2102页

作者： Júlia Farré-de-Pablo Joaquín A.Proenza JoséMaría González-jim.nez Thomas Aiglsperger Antonio Garcia-Casco Javier Escuder-viruete vanessa Colás Francisco Longo Departament de Mineralogia Petrologia i Geologia AplicadaUniversitat de BarcelonaC/Martíi Franquess/n08028BarcelonaSpain Departamento de Mineraloga y Petrologa Universidad de GranadaFacultad de CienciasFuentenueva s/n18002GranadaSpain Department of Civil Engineering and Natural Resources LuleåUniversity of TechnologySE 97187LuleåSweden Instituto Andaluz de Ciencias de la Tierra(CsIC-UGR) Avda.de las Palmeras 4E-18100ArmillaGranadaSpain Instituto Geologico y Minero de Espana C/La Calera 1Tres Cantos28760MadridSpain Instituto de Geología Universidad Nacional Autonoma de MéxicoCiudad Universitaria04510Ciudad de MéxicoMexico Facultad de Ingeniería Universidad Catòlica de CibaoLa VegaDominican Republic

Chromitite bodies hosted in peridotites typical of suboceanic mantle(***)are found in the northern and central part of the Loma Caribe peridotite,in the Cordillera Central of the Dominican *** chromitites are massive pods of small size(less than a few meters across)and veins that intrude both dunite and ***,they are high-Cr chromitites[Cr#=Cr/(Cr+Al)atomic ratio=0.71-0.83]singularly enriched in TiO2(up to 1.25 wt.%),Fe2 O3(2.77-9.16 wt.%)as well as some trace elements(Ga,v,Co,Mn,and Zn)and PGE(up to 4548 ppb in whole-rock).This geochemical signature is unknown for chromitites hosted in oceanic upper mantle but akin to those chromites crystallized from mantle plume derived ***,the melt estimated to be in equilibrium with such chromite from the Loma Caribe chromitites is similar to basalts derived from different source regions of a heterogeneous Caribbean mantle *** mantle plume is responsible for the formation of the Caribbean Large Igneous Province(CLIP).Dolerite dykes with back-arc basin basalt(BABB)and enriched mid-ocean ridge basalt(E-MORB)affinities commonly intrude the Loma Caribe peridotite,and are interpreted as evidence of the impact that the Caribbean plume had in the off-axis magmatism of the back-arc basin,developed after the Caribbean island-arc extension in the Late *** propose a model in which chromitites were formed in the shallow portion of the back-arc mantle as a result of the metasomatic reaction between the supra-subduction zone(ssZ)peridotites and upwelling plume-related melts.

关键词： Chromitite Ophiolite Plume Mantle Back-arc basin Dominican Republic

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Phylogeny,genetics,and the partial life cycle of Oncomegas wageneri in the Gulf of Mexico

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Current Zoology 2020年第3期66卷 275-283页

作者： Andrés MARTInez-AQUINO víctor M.vIDAL-MARTInez F.sara CECCARELLI Oscar MENDEZ Lilia C.sOLER-jim.nez M.Leopoldina AGUIRRE-MACEDO Facultad de Ciencias Universidad Autonoma de Baja CaliforniaCarretera Transpeninsular 3917Fraccionamiento PlayitasEnsenadaBaja California 22860Mexico Laboratorio de Patologia Acuatica Departamento de Recursos del MarCentro de Investigacion y de Estudios Avanzados del Instituto Politecnico NacionalUnidad MeridaCordemexCarretera Antigua a Progreso Km.6MeridaYucatan 97310Mexico Departamento de Biologia de la Conservacion CONACYT-Centro de Investigacion Cientifica y de Educacion Superior de EnsenadaCarretera Ensenada-TjuanaEnsenadaBaja California 22860Mexico Laboratorio de Hidrobiologia Facultad de Biologia-XalapaUniversidad VeracruzanaCircuito Gonzalo Aguirre Beltran S/N Zona UniversitariaXalapaVeracruz 91090Mexico

Despite the diversity and ecological importance of cestodes,there is a paucity of studies on their life stages(i.e.,complete lists of intermediate,paratenic,and definitive hosts)and genetic *** example,in the Gulf of Mexico(GoM)98 species of cestodes have been reported to date;however,data on their intraspecific genetic variation and population genetic studies are *** trypanorhynch cestode,Oncomegas wageneri,is found(among other places)off the American Western Atlantic Coast,including the GoM,and has been reported as an adult from stingrays and from several teleost species in its larval form(as plerocerci).This study represents the first report of 2 previously unregistered definitive hosts for ***,namely the Atlantic sharpnose shark Rhizoprionodon terraenovae and the southern stingray Hypanus *** this work,partial sequences of the 28s(region D1-D2)ribosomal DNA were analyzed to include *** within an eutetrarhynchoid phylogenetic *** *** individuals(which included plerocerci and adults)were recovered as monophyletic and Oncomegas celatus was identified as the sister species of ***,population genetic analyses of *** from the southern GoM were carried out using DNA sequences of the mitochondrial cytochrome c oxi-dase subunit 1(COI)gene,which reflected high genetic variation and a lack of genetic structure among the 9 oceanographic sampling *** on these results,*** is panmictic in the southern *** extensive sampling along the species entire distribution is necessary to make more accurate inferences of population genetics of ***.

关键词： barcode Cyclopsetta chittendeni population genetics Hypanus americanus Oncomegas Rhizoprionodon terraeno-vae 28s rDNA(D1-D2)

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