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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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Cluster Analysis of the Roma-BZCAT Blazars

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Research in Astronomy and Astrophysics 2024年第5期24卷 117-139页

作者： Dmitry O.Kudryavtsev yulia v.Sotnikova vladislav A.Stolyarov Timur v.Mufakharov valery v.vlasyuk Margarita L.Khabibullina Alexander G.Mikhailov yulia v.Cherepkova Special Astrophysical Observatory of the Russian Academy of Sciences Nizhny Arkhyz 369167Russia Astrophysics Group Cavendish LaboratoryUniversity of CambridgeCambridge CB3 OHEUK Kazan Federal University 18 Kremlyovskaya StKazan 420008Russia

Based on the collected multiwavelength data, namely in the radio(NvSS, FIRST, RATAN-600), IR(WISE),optical(Pan-STARRS), Uv(GALEX), and X-ray(ROSAT, Swift-XRT) ranges, we have performed a cluster analysis for the blazars of the Roma-BZCAT catalog. Using two machine learning methods, namely a combination of PCA with k-means clustering and Kohonen's self-organizing maps(SOMs), we have constructed an independent classification of the blazars(five classes) and compared the classes with the known Roma-BZCAT classification(FSRQs, BL Lacs, galaxy-dominated BL Lacs, and blazars of an uncertain type) as well as with the high synchrotron peaked(HSP) blazars from the 3HSP catalog and blazars from the TevCat catalog. The obtained groups demonstrate concordance with the BL Lac/FSRQ classification along with a continuous character of the change in the properties. The group of HSP blazars stands out against the overall distribution. We examine the characteristics of the five groups and demonstrate distinctions in their spectral energy distribution shapes. The effectiveness of the clustering technique for objective analysis of multiparametric arrays of experimental data is demonstrated.

关键词： methods data analysis-galaxies active-(galaxies:)BL Lacertae objects general

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Ataxia-telangiectasia mutated plays an important role in cerebellar integrity and functionality

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Neural Regeneration Research 2023年第3期18卷 497-502页

作者： yulia Mitiagin Ari Barzilai Department of Neurobiology the School of NeurobiologyBiophysicsMolecular Biology and BiochemistryGeorge S.WiseFaculty of Life SciencesTel Aviv UniversityTel AvivIsrael Sagol School of Neurosciences Tel Aviv UniversityTel AvivIsrael

Accumulating evidence indicates that ataxia-telangiectasia mutated kinase is critical for maintaining cellular homeostasis and that it has both nuclear and cytoplasmic ***,the functions of ataxia-telangiectasia mutated that when lost lead to cerebellar degeneration are still *** this review,we first describe the role of ataxia-telangiectasia mutated in cerebellar *** addition to its canonical nuclear functions in DNA damage response circuits,ataxia-telangiectasia mutated functions in various cytoplasmic and mitochondrial processes that are critically important for cellular *** discuss these functions with a focus on the role of ataxia-telangiectasia mutated in maintaining the homeostatic redox ***,we describe the unique functions of ataxia-telangiectasia mutated in various types of neuronal and glial cells including cerebellar granule neurons,astrocytes,and microglial cells.

关键词： ataxia telangiectasia ATM cerebellum DNA damage response double-strand breaks mitochondrial dysfunction oxidative stress single-strand breaks

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Waxes in asphaltenes of crude oils and wax deposits

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Petroleum Science 2016年第4期13卷 737-745页

作者： yulia M.Ganeeva Tatiana N.Yusupova Gennady v.Romanov A.E. Arbuzov Institute of Organic and Physical Chemistry Kazan Scientific Center Russian Academy of Sciences Institute of Geology and Petroleum Technologies Kazan (Volga region) Federal University

Composition and molecular mass distribution of n-alkanes in asphaltenes of crude oils of different ages and in wax deposits formed in the borehole equipment were studied. In asphaltenes, n-alkanes from C12 to C60 were detected. The high molecular weight paraffins in asphaltenes would form a crystalline phase with a melting point of 80–90 ℃. The peculiarities of the redistribution of high molecular paraffin hydrocarbons between oil and the corresponding wax deposit were detected. In the oils, the high molecular weight paraffinic hydrocarbons C50–C60were found, which were not practically detected in the corresponding wax deposits.

关键词： Waxes Asphaltenes Hydrocarbon composition Crude oil Wax deposit

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Combined effect of surface microgeometry and adhesion in normal and sliding contacts of elastic bodies

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Friction 2017年第3期5卷 339-350页

作者： Irina GORYACHEvA yulia MAKHOvSKAYA Institute for Problems in Mechanics of the Russian Academy of Sciences Pr.Vernadskogo 101-1 Moscow 119526 Russia

In this study,models are proposed to analyze the combined effect of surface microgeometry and adhesion on the load-distance dependence and energy dissipation in an approach-separation cycle,as well as on the formation and rupture of adhesive bridges during *** models are based on the Maugis-Dugdale approximation in normal and frictional (sliding and rolling) contacts of elastic bodies with regular surface *** the normal adhesive contact of surfaces with regular relief,an analytical solution,which takes into account the mutual effect of asperities,is *** contribution of adhesive hysteresis into the sliding and rolling friction forces is calculated for various values of nominal pressure,parameters of microgeometry,and adhesion.

关键词： adhesion roughness discrete contact rolling friction sliding friction

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Growth of Micropropagated Solanum tuberosum *** under Artificial Solar Spectrum and Different Mono-and Polychromatic LED Lights

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Horticultural Plant Journal 2022年第2期8卷 205-214页

作者： Olga v.Grishchenko Eugeny P.Subbotin Irina v.Gafitskaya yulia v.vereshchagina Elena v.Burkovskaya yulia A.Khrolenko valeria P.Grigorchuk Olga v.Nakonechnaya victor P.Bulgakov Yuri N.Kulchin Federal Scientific Center of the East Asia Terrestrial Biodiversity Far Eastern Branch of the Russian Academy of SciencesVladivostok 690022Russia Institute of Automation and Control Processes Far Eastern Branch of the Russian Academy of SciencesVladivostok 690041Russia

In agriculture,LED light sources have increasingly replaced the standard luminescent lamps and have acquired an important role in plant *** studied the effect of different light sources such as narrow-band LEDs(bright blue,blue,green,yellow,deep red,and red)and wide-band LEDs(cold white,white,warm white,full spectrum,and an artificial solar spectrum sun box constructed by us)on development of potato plantlets in *** luminescent lamps were used as a *** light intensity of 49μmol·m^(-2)·s^(-1)was provided in all light *** showed that the long-wave narrow-band light treatments were inapplicable for potato micropropagation,because plantlets were weak with small leaves,inhibited roots,and significantly elongated *** lights provided growth of shortened plantlets with large leaves,well-growing roots,and abundant green *** chlorophyll content was lower under blue and bright blue light and was at the same level in the remained *** differences in the stomatal apparatus development were observed depending on the light *** differences were not always reflected in the plantlet phenotype:e.g.,plantlets under blue and bright blue lights showed no differences in any characteristics except stomatal density and size of stomatal guard *** found no significant effect of blue light portion in the white lights and full spectrum on plantlet *** artificial solar spectrum sun box was the most suitable for potato micropropagation,because it supported the development of plantlets with good fitness,uniform internodes length,abundant roots and green mass accumulation.

关键词： Solanum tuberosum LED Artificial solar light Growth Micropropagation

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Expansion of Juniperus sibirica *** a response to climate change and associated effect on mountain tundra vegetation in the Northern Urals

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Journal of Mountain Science 2020年第10期17卷 2339-2353页

作者： Andrey A.GRIGORIEv yulia v.SHALAUMOvA Olga v.EROKHINA Svetlana Yu.SOKOvNINA Elizaveta I.vATOLINA Martin WILMKING Institute of Plant and Animal Ecology UB RAS Laboratory of Geoinformation TechnologyEkaterinburgRussia Institute of Industrial Ecology UB RAS Laboratory of Mathematical Modeling in Ecology and MedicineEkaterinburgRussia Institute of Plant and Animal Ecology UB RAS Laboratory of Vegetation and Mycobiota BiodiversityEkaterinburgRussia Institute of Plant and Animal Ecology UB RAS Laboratory of Dynamics of Arctic EcosystemsLabytnangiRussia Department of Forest Taxation and Forest Management Institute of Forest and Nature ManagementUral state Forest Engineering UniversityEkaterinburgRussia Institute for Botany and Landscape Ecology Greifswald UniversityGreifswaldGermany

Shrub expansion into arctic and alpine tundra is one of the prominent vegetation changes currently *** studied the expansion of shrub vegetation into high elevation tundra in the Kvarkush Range of the Northern Ural mountains,*** structure analysis of the dominant shrub Juniperus sibirica *** to support ongoing upslope advance of shrubs,a process particularly active in the second half of the 20 th *** found a close connection between the expansion of shrub vegetation and the general change in climatic conditions of the cold season(months with mean airtemperature below 0°Сfrom November to March).In general,the greatest influence on the distribution of *** is exerted by the climate conditions of the beginning(November-January)and the end(March)of the cold *** increasing elevation,the correlation coefficients between the establishment of *** shrubs and the precipitation of the beginning of the cold season increased,and reached maximum values at the top elevation level of the study ***,the upwards shift of *** into typical mountain tundra does not lead to changes in the ecological structure of vegetation at this stage,but simply a decrease in the area of mountain tundra.

关键词： Juniperus sibirica Expansion Tundra vegetation Plant communities Climate changes Northern Ural mountains

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Mathematical modeling of building structures and nonlinear differential equations

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International Journal of Modeling, Simulation, and Scientific Computing 2020年第3期11卷 154-160页

作者： victor Orlov yulia Zheglova Moscow State University of Civil Engineering Yaroslavskoye Shosse 26 Moscow 129337Russia

Nonlinear differential equations with moving singular points require emergence and development of new approximate methods of *** this paper,we give a solution to one of the problems of the analytical approximate method for solving nonlinear differential equations with moving singular points,and study the influence of the perturbation of the initial conditions on the analytical approximate solution in the analytic *** material was tested using a numerical experiment confirming its *** theoretical material presented in this paper allows researchers to use nonlinear differential equations with moving singular points when designing mathematical models of building structures.

关键词： Mathematical modeling moving singular points a priori estimate approximate solution a posteriori error estimate

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Experimental and ab initio study of Ba_(2)Na_(3)(B_(3)O_(6))_(2)F stability in the pressure range of 0–10 GPa

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International Journal of Minerals,Metallurgy and Materials 2023年第9期30卷 1846-1854页

作者： Nursultan E.Sagatov Tatyana B.Bekker yulia G.vinogradova Alexey v.Davydov Ivan v.Podborodnikov Konstantin D.Litasov Sobolev Institute of Geology and Mineralogy Siberian Branch of Russian Academy of SciencesNovosibirsk 630090Russia Department of Geology and Geophysics Novosibirsk State UniversityNovosibirsk 630090Russia Research and Development Department Novosibirsk State University of ArchitectureDesign and Arts(NSUADA)Novosibirsk 630099Russia vereshchagin Institute for High Pressure Physics Russian Academy of SciencesTroitsk 108840Russia Fersman Mineralogical Museum Russian Academy of SciencesMoscow 119071Russia

Both numerical and experimental studies of the stability and electronic properties of barium–sodium metaborate Ba_(2)Na_(3)(B_(3)O_(6))_(2)F(P63/m) at pressures up to 10 GPa have been carried out. Electronic-structure calculations with HSE06 hybrid functional showed that Ba_(2)Na_(3)(B_(3)O_(6))_(2)F has an indirect band gap of 6.289 ev. A numerical study revealed the decomposition of Ba_(2)Na_(3)(B_(3)O_(6))_(2)F into the BaB_(2)O_(4),Na BO_(2), and NaF phases above 3.4 GPa at 300 K. Subsequent high-pressure high-temperature experiments performed using ‘Discoverer-1500’DIA-type apparatus at pressures of 3 and 6 GPa and temperature of 1173 K confirmed the stability of Ba_(2)Na_(3)(B_(3)O_(6))_(2)F at 3 GPa and its decomposition into BaB_(2)O_(4), NaBO_(2), and NaF at 6 GPa, which was verified by energy-dispersive X-ray analysis and Raman spectroscopy. The observed Raman bands of the Ba_(2)Na_(3)(B_(3)O_(6))_(2)F phase were assigned by comparing the experimental and calculated spectra. The experimental Raman spectra of decomposition reaction products obtained at 6 GPa suggest the origin of a new high-pressure modification of barium metaborate BaB_(2)O_(4).

关键词： density functional theory phase stability borate high pressure Raman spectroscopy

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Explosive-Emission Plasma Dynamics in Ion Diode in Double-Pulse Mode

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Plasma Science and Technology 2011年第6期13卷 698-701页

作者： Alexander I.PUSHKAREv yulia I.ISAKOvA Tomsk Polytechnic University

The results of an experimental investigation of explosive-emission plasma dynamics in an ion diode with self-magnetic insulation are presented. The investigations were accomplished at the TEMP-4M accelerator set in a mode of double pulse formation. Plasma behaviour in the anode-cathode gap was analyzed according to both the current-voltage characteristics of the diode （time resolution of 0.5 ns） and thermal imprints on a target （spatial resolution of 0.8 mm）. It was shown that when plasma formation at the potential electrode was complete, and up until the second （positive） pulse, the explosive-emission plasma expanded across the anode-cathode gap with a speed of 1.3±0.2 cm/μs. After the voltage polarity at the potential electrode was reversed （second pulse）, the plasma erosion in the anode-cathode gap （similar to the effect of a plasma opening switch） occurred. During the generation of an ion beam the size of the anode-cathode gap spacing was determined by the thickness of the plasma layer on the potential electrode and the layer thickness of the electrons drifting along the grounded electrode.

关键词： ion beams graphite cathodes plasma speed self-magnetic insulation

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