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Phosphine/Benzocyclone-based Neutral Nickel Catalysts for Ethylene Polymerization and Copolymerization with Polar Monomers

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Chinese Journal of Polymer Science 2024年第2期42卷 202-212,I0007页

作者： Fei Wang Li Pan vladislav a.tuskaev Svetlana Ch.Gagieva Yue-Sheng Li Tianjin Key Lab of Composite&Functional Materials School of Material Science and EngineeringTianjin UniversityTianjin300072China Department of Chemistry Lomonosov Moscow State UniversityRussian Federation InstitutionLeninskie Gory 1Moscow119991Russian Federation A N Nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesVavilova st.28Moscow119991Russian Federation

The efficient copolymerization of olefin with polar monomers using nickel-based catalysts presents a longstanding challenge. In this contribution, three phosphine-benzocyclone ligands and corresponding neutral nickel catalysts(Ni1: Ar = Ph;Ni2: Ar = 2-(C_(6)H_(5))C_(6)H_(4);Ni3: Ar = 2-[2',6'-(Me O)_(2)-C_(6)H3]C_(6)H_(4)) were prepared and applied for the ethylene polymerization and copolymerization with polar monomers without any cocatalyst. The bulky substituent groups in complexes Ni2 and Ni3 contributed to high catalytic activities(up to 7.24×10^(6) and 9.04×10^(6)g·mol Ni^(-1)·h^(-1), respectively), and produced high-molecular-weight polyethylene(Mw up to 545.7 k Da). Complex Ni3 exhibited high activities for ethylene polymerization at the level of 10^(6) g·mol Ni^(-1)·h^(-1) across a wide range from 30 ℃ to 120 ℃, exhibiting excellent high temperature tolerance. These nickel complexes were also effectively employed in the copolymerization of ethylene with methyl acrylate, ethyl acrylate, butyl acrylate and lauryl acrylate, producing copolymers with high molecular weights(Mw up to 80.5 k Da) and high polar monomer incorporation(up to 8.2 mol%). Microstructure analyses revealed that the introduction of large sterically hindered substituents facilitated the incorporation of polar functional units into the polymer backbone. This study demonstrates the potential of these nickel-based catalysts for efficient copolymerization of olefin with polar monomers.

关键词： Neutral nickel catalyst Ethylene polymerization Copolymerization Polar acrylate monomers

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Trapping the Short-Chain Odd Carbon Number Olefins Using Nickel(Ⅱ)-Catalyzed Tandem Ethylene Oligomerization and Friedel-Crafts Alkylation of Toluene

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Chinese Journal of Chemistry 2023年第21期41卷 2855-2865页

作者： Sergey V.Zubkevich vladislav a.tuskaev Svetlana Ch.Gagieva Alexander A.Pavlov Victor N.Khrustalev Fei Wang Li Pan Yuesheng Li Daniele Saracheno Anton A.Vikhrov Dmitry N.Zarubin Boris M.Bulychev Department of Chemistry Lomonosov Moscow State UniversityLeninskie Gory 1Moscow119991 Russian Federation Materials Research and Technology Department Luxembourg Institute of Science and Technology5Avenue des Hauts-FourneauxL-4362 Esch-sur-AlzetteLuxembourg A N Nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesVavilova st.28Moscow119991 Russian Federation BMSTU Center of National Technological Initiative“Digital Material Science:New Material and Substances” Bauman MoscowState Technical University2nd Baumanskaya st.5MoscowRussian Federation Peoples’Friendship University of Russia(RUDN University) Miklukho-Maklay St.6Moscow117198 Russian Federation Zelinsky Institute of Organic Chemistry Russian Academy of SciencesLeninsky Prospekt 47Moscow119991 Russian Federation Institute of Advanced Polymer Materials School of Materials Science and EngineeringTianjin UniversityTianjin300350 China

Nickel(Ⅱ)complexes with pyrazole-based ligands are widely employed in catalysis of ethylene oligomerization and subsequent Friedel-Crafts alkylation of *** have prepared ten new nickel(Ⅱ)dibromide complexes with various substituted bis(azolyl)*** have been characterized using^(1)H NMR,IR,high resolution mass spectrometry and elemental *** structures of three complexes have been unambiguously established using X-ray *** was found that these complexes in the presence of Et2AlCl or Et_(3)Al_(2)Cl_(3)are active both in ethylene oligomerization and Friedel-Crafts alkylation processes(activity up to 3720 kgoligomer·mol[Ni]^(−1)·h^(−1)).The use of Et_(3)Al_(2)Cl_(3)results in a higher share of alkylated products(up to 60%).Moreover,catalytic systems activated with Et_(3)Al_(2)Cl_(3)produced small amounts of odd carbon number olefins(up to 0.8%).The Friedel-Crafts alkylation was used as a trap for previously undetected short-chain odd carbon number olefins(C_(3)and C_(5)).

关键词： Ethylene oligomerization Friedel-Crafts alkylation Nickel(Ⅱ)complexes N-ligands Odd carbon number olefins

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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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Binuclear and Hexanuclear Ti(Ⅳ) Complexes Supported by [OOOO]^(4–)-type Ligand for Preparing Disentangled UHMWPE

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Chinese Journal of Polymer Science 2019年第5期37卷 471-477页

作者： vladislav a.tuskaev Svetlana Ch.Gagieva Dmitry A.Kurmaev Viktor G.Vasil'ev Nikolay A.Kolosov Sergey V.Zubkevich Elena S.Mikhaylik Evgenii K.Golubev Galina G.Nikiforova Pavel A.Zhizhko Olga A.Serenko Boris M.Bulychev Department of Chemistry M.V.Lomonosov Moscow State University A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of Sciences Enikolopov Institute of Synthetic Polymer Materials Russian Academy of Sciences

Binuclear and hexanuclear titanium complexes stabilized by tetradentate [OOOO]^(4–)-type ligand were active in ethylene polymerization in the presence of Et2 AlCl/Bu2 Mg binary co-catalyst, giving high molecular weight polyethylene. The binuclear complex showed significantly higher catalytic activity and thermal stability in comparison to mononuclear analogue. Ultra high molecular weight polyethylene(UHMWPE) samples were processed by a solid-state uniaxial deformation into high-strength(up to 2.5 GPa) and highmodulus(over 100 GPa) oriented film tapes, which indirectly indicates a low degree of entanglements between the macromolecular chains.

关键词： Binuclear catalysts Titanium Ethylene Ziegler-Natta polymerization UHMWPE

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Central Asia—A Global Model for the Formation of Epigenetic Deposits in a Platform Sedimentary Cover

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Journal of Earth Science 2022年第2期33卷 278-288页

作者： Igor Pechenkin vladislav Petrov FSBI All-Russian Scientific-Research Institute of Mineral Resources MoscowRussia Institute of Geology of Ore Deposits Petrography Mineralogy and Geochemistry RAS MoscowRussia

Metallogenic specialization of sedimentary cover in Central Asia is determined by its tectonic setting that governs the hydrodynamic regime(exfiltrational or infiltrational)and as a consequence,the hydrogeochemical zonality(type of water and its gaseous and microcomponent composition).Hydrodynamic conditions(distribution of recharge and discharge areas)determine the direction of stratal water flow and location of mineralization resulted from the change in geochemical,thermodynamic,lithological,structural and other *** exfiltrational regime suggests a dependence of the epigenetic mineralization upon the distribution and degree of preservation of hydrocarbon ***,hydrocarbon matter serves as a reducing barrier and ore-concentrating factor during the formation of polymineral concentrations related to stratal oxidation *** supergene epigenetic ore-forming processes are induced by the interaction between the Earth’s sedimentary cover and *** rocks themselves commonly serve as a source of ore *** ore deposition zones on geochemical barriers and ore material source are often located significantly apart from each *** trend of these processes is determined by the position of ore-bearing depressions in large tectonic blocks.

关键词： Central Asia Kyzyl Kum Bukantau ore-forming systems epigenetic ore deposit geology

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Interactive mobile equipment safety task-training in surface mining

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International Journal of Mining Science and Technology 2021年第4期31卷 743-751页

作者： Lazar Zujovic vladislav Kecojevic Dragan Bogunovic Department of Mining Engineering West Virginia UniversityMorgantown 26501USA North American Coal Corporation Farmington 87401USA

Improving the quality of equipment training for the Heavy Equipment Operators(HEO)is a critical task in improving safety and eliminating equipment-related injuries in *** of major responsibilities for the HEOs is proper machine *** miner safety training includes the use of hardcopy documents and video ***,modern mobile and computer technology offers tremendous potential to improve the training *** this study,we apply a 360-degree camera,opensource platform WordPress^(TM),and the software Unity3D in order to create materials and tools for the HEOs safety training to help trainees better understand the pre-shift safety machine *** computer-based safety task training developed in this research is tested and implemented at a surface mine in the southern United States.

关键词： Heavy equipment operators Safety task training 360-degree image/video Virtual reality

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Theoretical and experimental studies of gas preparation system for pressurization and reactive control system of launch vehicle

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Chinese Journal of Aeronautics 2024年第7期37卷 168-177页

作者： Valeriy TRUSHLYAKOV vladislav URBANSKY Vadim YUDINTSEV Department of Aviation and Rocket Building Omsk State Technical UniversityOmsk 644050Russia

A new gas preparation system(GasPS-RCS)is proposed to solve two tasks:(A)to heat helium gas for tank pressurization;(B)to prepare gas for the Launch Vehicle(LV)Reactive Control System(RCS)at the LV orientation and stabilization sections of the LV on passive parts of the flight trajectory,to provide conditions for launching the Liquid Rocket Engine(LRE).The system includes a gas generator based on hydrogen peroxide,a separator for water separation,heat exchangers independent of the LRE,and gas-jet *** proposed new system allowed to reduce the length of pressurizing gas lines and reduce the increased helium gas consumption during the heat exchanger warm-up interval of the LRE during its launch.A special advantage of the proposed system is the possibility of ground testing of heat exchangers without an operating LRE.A mathematical model based on the first law of thermodynamics was used to perform a comparative analysis of GasPS-RCS with traditional pressurization and RCS *** validate the mathematical model,the experimental studies of helium pressurizing of a liquid nitrogen tank were *** results show that the deviation of experimental and calculated values for pressure is 1.1%and for temperature up to 2%.According to the results of comparative analysis,the GasPS-RCS is 259 kg lighter for the first stage and 80 kg lighter for the second stage of the LV.

关键词： Engine restart Reactive control system Tank pressurization Cryogenics Hydrogen peroxide Heat exchanger

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Age and chemical composition of the globular cluster NGC 6652

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Research in Astronomy and Astrophysics 2020年第8期20卷 252-260页

作者： Margarita Eugene Sharina vladislav Vladimirovich Shimansky Special Astrophysical Observatory Russian Academy of SciencesNizhnii Arkhyz369 l67Russia Kazan Federal University 18 Kremlyovskaya streetKazan420008Russia

We present the results of determination of the age,helium mass fraction(Y),metallicity([Fe/H]),and abundances of the elements C,N,O,Na,Mg,Ca,Ti,C and Mn for the Galactic globular cluster NGC *** use its medium-resolution integrated-light spectrum from the library of Schiavon and our population synthesis method to fulfill this *** select the evolutionary isochrone and stellar mass function for our analysis,which provide the best approximation to the shapes and intensities of the observed Balmer line *** determined elemental abundances,age and metallicity are characteristic of stellar populations in the Galactic Bulge.

关键词： globular clusters:general globular clusters:abundances globular clusters:individual:NGC 6652

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Evaluation of rope shovel operators in surface coal mining using a Multi-Attribute Decision-Making model

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International Journal of Mining Science and Technology 2014年第2期24卷 259-268页

作者： Vukotic Ivana Kecojevic vladislav Department of Mining Engineering West Virginia University

Rope shovels are used to dig and load materials in surface mines. One of the main factors that influence the production rate and energy consumption of rope shovels is the performance of the operator. This paper presents a method for evaluating rope shovel operators using the Multi-Attribute Decision-Making （MADM） model. Data used in this research were collected from an operating surface coal mine in the southern United States. The MADM model consists of attributes, their weights of importance, and alter- natives. Shovel operators are considered the alternatives, The energy consumption model was developed with multiple regression analysis, and its variables were included in the MADM model as attributes. Preferences with respect to min/max of the defined attributes were obtained with multi-objective opti- mization. Multi-objective optimization was conducted with the overall goal of minimizing energy con- sumption and maximizing production rate. Weights of importance of the attributes were determined by the Analytical Hierarchy Process （AHP）, The overall evaluation of operators was performed by one of the MADM models, i.e., PROMETHEE If. The research results presented here may be used by mining professionals to held evaluate the performance of rode shovel operators in surface mining.

关键词： Rope shovel Operator evaluation Production rate Energy consumption AHP

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TRANSCRANIAL NEAR-INFRARED SPECTROSCOPY OF SMOKING BRAINS

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Journal of Innovative Optical Health Sciences 2009年第3期2卷 227-234页

作者： OLIVIA PUCCI SANDER STEPANOV vladislav TORONOV Department of Physics Ryerson University 350 Victoria StreetTorontoONCanada M5B 2K3

We used a mobile wireless near-infrared sensor for the noninvasive recording of cerebral hemoglobin concentration changes during cigarette *** measurement included 5 min of rest,5 min of smoking imitation,and 5 min of actual *** observed significant effects of the tobacco smoking on temporal changes in the human brain at time scales ranging from 200 ms to about 1 *** most reproducible effects were an increase of the heartbeat rate and a decrease in the heartbeat power spectral density during *** but highly individual changes due to smoking were observed in temporal patterns of hemodynamic fluctuations in 5–50 s time *** have also found statistically significant slow increases in both oxy-and deoxy-hemoglobin concentrations during smoking.

关键词： Near-infrared spectroscopy hemoglobin brain smoking

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