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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

Parasites of the liver:A global problem?

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World Journal of Gastroenterology 2024年第30期30卷 3554-3559页

作者： vladislav V Tsukanov Alexander V Vasyutin Julia L Tonkikh Clinical Department of the Digestive System Pathology of Adults and Children Federal Research Center“Krasnoyarsk Science Center”of the Siberian Branch of the Russian Academy of SciencesScientific Research Institute of Medical Problems of the NorthKrasnoyarsk 660022Russia

Parasitic liver diseases can be caused by trematodes,cestodes,nematodes,and *** pathology is significant because millions of people in different parts of the world have liver parasites,which can manifest themselves in the development of inflammation,liver cysts,cholecystitis,cholelithiasis,pancreatitis and liver cirrhosis that are often threatening their *** International Agency for Research on Cancer considers three species of trematodes,Schistosoma haematobium,Opisthorchis viverrini and Clonorchis sinensis,to be *** modern examination methods,in some cases including extensive screening of large populations,are required for diagnosing liver *** of parasitic liver diseases is differentiated and can involve a combination of surgical and therapeutic *** is no doubt that the clinical and epidemiological scale allows one to regard parasitic liver diseases as a global healthcare problem.

关键词： Liver Parasites Epidemiology Diagnosis Clinics Treatment Echinococcosis Opisthorchiasis Fascioliasis Schistosomiasis

Change in Grain-Size Composition of Lignite under Cyclic Freezing-Thawing and Wetting-Drying

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Natural Resources 2024年第1期15卷 17-27页

作者： Natalia S. Batugina vladislav I. Fedorov Chersky Institute of Mining of the North Siberian Branch Russian Academy of Sciences Yakutsk Russia

The paper presents the change in grain-size composition of lignite under cyclic freezing-thawing (FTC) and wetting-drying (WDC). The article shows that in the spring and autumn periods the lignites can be subjected to repeated freezing-thawing and wetting-drying, which determines the possibility of changing their grain-size composition and structure. Experimental studies in laboratory conditions on the influence of cyclic freezing-thawing (FTC) and wetting-drying (WDC) on the quality indicators of lignites have been carried out, their granulometric (fractional) composition has been studied. Freezing-thawing cycle conditions are as follows (FTC): minimum exposure temperature: -20°C;maximum: +5°C;relative humidity: 30%;number of processing cycles: 3. Wetting-drying cycles are as follows (WDC): drying temperatures are +20, +40, +60, +80°C, drying time 90 minutes, the coals are further subjected to rain (soaking) for a period of water saturation to humidity of 30% - 40% and dry again. The number of wetting-drying cycles is 3 times. The tests have revealed the destructive effects of FTC and WDC on the samples of lower metamorphic grade coal, and the cycles of wet-dry lead to the much higher yield of fine sizes (-6+0;-13+0 mm) than the cycles of freeze-thaw. Furthermore, it is found that the increase in the yield of fines depends on the heating temperature: coal disintegration proceeds more intensively at a higher temperature of drying.

关键词： Lignite Freezing-Thawing Cycle Wetting-Drying Cycle Grain Size Composition Dust Coal Storage Loss Quality

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

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

非洲最恐怖的生命禁区一百年里无人敢涉足的达洛尔

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环球人文地理 2024年第5期 96-103页

作者：李理 vladislav Radek Benot ArtushFoto Lina dinozzaver Michail mikhail cheremkin flickr

色彩绚丽的盐层让人称奇，强酸性的湖水腐蚀鞋子，车队时不时被袭击，还曾有游客被撕票……达洛尔深刻诠释了什么叫“越迷人的越危险”。达洛尔位于埃塞俄比亚东北角，被描述成一个鬼城。因为2005年之后，埃塞俄比亚中央统计局的人口报...

色彩绚丽的盐层让人称奇，强酸性的湖水腐蚀鞋子，车队时不时被袭击，还曾有游客被撕票……达洛尔深刻诠释了什么叫“越迷人的越危险”。达洛尔位于埃塞俄比亚东北角，被描述成一个鬼城。因为2005年之后，埃塞俄比亚中央统计局的人口报告中，就已没有此地区的人口数据。这里是世界上最遥远、最荒芜的地区之一，没有学校、没有商店，也没有公路，对外交通除了游客车队，就只有前往该地收集盐块的阿法尔人与骆驼。然而，这里的形势极不稳定，

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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

Unraveling effects of electron correlation in two-dimensional Fe_(n)GeTe_(2)(n=3,4,5)by dynamical mean field theory

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npj Computational Materials 2023年第1期9卷 1453-1468页

作者： Sukanya Ghosh Soheil Ershadrad vladislav Borisov Biplab Sanyal Department of Physics and Astronomy Uppsala UniversityBox-51675120 UppsalaSweden

The Fe_(n)GeTe_(2) systems are recently discovered two-dimensional van-der-Waals materials,exhibiting magnetism at room *** sub-systems belonging to Fe_(n)GeTe_(2) class are special because they show site-dependent magnetic *** focus on the critical evaluation of magnetic properties and electron correlation effects in Fe_(n)GeTe_(2)(n=3,4,5)(FGT)systems performing first-principles *** different ab initio approaches have been used primarily,viz.,(i)standard density functional theory(GGA),(ii)incorporating static electron correlation(GGA+U)and(iii)inclusion of dynamic electron correlation effect(GGA+DMFT).Our results show that GGA+DMFT is the more accurate technique to correctly reproduce the magnetic interactions,experimentally observed transition temperatures and electronic *** inaccurate values of magnetic moments,exchange interactions obtained from GGA+U make this method inapplicable for the FGT *** determination of magnetic properties for this class of materials is important since they are promising candidates for spin transport and spintronic applications at room temperature.

关键词： temperature theory dimensional

Microfracture Characterization in Sandstone Reservoirs:A Case Study from the Upper Triassic of Syria's Euphrates Graben

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Journal of Earth Science 2022年第4期33卷 901-915页

作者： Ibrahem Yousef Vladimir Morozov vladislav Sudakov Ilyas Idrisov Institute of Geology and Petroleum Technologies Kazan Federal UniversityKazan 420111Russia

The Euphrates Graben is located in eastern *** Upper Triassic Mulussa F Formation sandstones serve as the primary reservoir intervals in the majority of the graben *** study’s findings were based on core studies:petrographic examination of thin sections,scanning electron microscope(SEM),imaging of backscatter scanning electron microscope(BSE),X-ray microprobe examinations,and carbon-oxygen stable isotope analysis of microfracture-filling *** of the most common types of microfracture found in the investigated sandstones are intragranular or intracrystalline microfractures,grain boundary or grain-edge microfractures,and transgranular(crossing grains)*** microfractures that are open and free of secondary mineralization improve sandstone storage and ***,microfractures that are cemented and filled with secondary mineralization reduce storage and *** siderite and pyrite cements were identified within the microfractures and the nearby sandstone *** anhedral or euhedral siderites are thought to form during shallow burial diagenesis,whereas poikilotopic siderites are thought to form during deep burial *** pyrite is believed to be a diagenetic cement,which is attributed to the reduction of iron oxides present in the sediments in the presence of *** reflect tectonic,overpressure,and diagenetic *** of tectonic origin are associated with folding and thrust activities over the Euphrates Graben area,and they were formed at the beginning of the Upper Triassic with siderite and pyrite cement equilibration temperatures of approximately 100–105℃,and they continued forming from the middle to the end of the Upper Triassic with cement equilibration temperatures of approximately 90–100℃in conjunction with the first phase of the Euphrates *** related to diagenetic and overpressure processes are tension microfractures and wer

关键词： microfracture sandstone Upper Triassic Mulussa F Euphrates Graben Syria

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