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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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Boosting propane dehydrogenation by gallium hydride species formed in situ

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Science China Chemistry 2024年第6期67卷 1753-1755页

作者： evgenii V.kondratenko Leibniz-Institut für katalyse e.V. Albert-Einstein-Str.29aRostock18059Germany

An inspiring paper recently published in Nature Chemistry[1]by the group of *** Gong at Tianjin University is the motivation for this highlight *** reported results show that the understanding of reaction-induced restructuring of heterogeneous catalysts is of great importance for their targeted development because usually unstable compounds can be formed and stabilized under reaction conditions.

关键词： conditions hydride stabilized

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Model of fractured medium and nondestructive control of composite materials

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Chinese Journal of Aeronautics 2024年第2期37卷 93-99页

作者： Vasily golubev Ilia NIkITIN katerina BEkLEMYSHEVA Department of Computers Science and Numerical Mathematics Moscow Institute of Physics and TechnologyDolgoprudny 141700Russia Mathematical Modeling and Management Department of InformatizationInstitute of Computer Aided Design RASMoscow 123056Russia

Non-destructive testing of composites is an important issue in the modern aircraft *** are susceptible to the barely visible impact damage which can affect the residual strength of the material and occurs both during production and *** continuum model for describing the damaged zone is *** slip theory relations used for a continuous distribution of slip planes are *** the initial stage,the isotropic background model is *** model allows the material slippage along the fractures based on the Coulomb friction law with the small viscous *** this regime,the govern system of equations becomes *** overcome this difficulty,the explicit-implicit grid-characteristic scheme is *** standard ultrasound diagnostic procedure of damaged composite materials is successfully *** with the trivial free-surface fracture model,different reactions on the compression and stretch waves are *** approach provided an effective way for the simulation of complex dynamic behavior of damage zones.

关键词： Non-destructive testing Composite materials Numerical modeling Continuum model Grid-characteristic method

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Expanded Porphyrin Exhibiting Off-Centered Out-of-Plane Coordination to Dysprosium

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CCS Chemistry 2024年第7期6卷 1731-1738页

作者： Dmitry I.Nazarov Jorge Labella Alexey V.kuzmin Maxim A.Faraonov evgenii N.Ivanov Salavat S.khasanov Tomas Torres Mikhail k.Islyaikin Dmitri V.konarev Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry RAS 142432 Chernogolovka Department of Organic Chemistry Universidad Autonoma de Madrid28049 Madrid Institute of Solid-State Physics RAS 142432 Chernogolovka Research Institute of Macroheterocycles Ivanovo State University of Chemistry and Technology15300 Ivanovo G.A.krestov Institute of Solution Chemistry of the Russian Academy of Sciences 153045 Ivanovo Institute for Advanced Research in Chemical Sciences Universidad Autonoma de Madrid28049 Madrid IMDEA-Nanociencia 28049 Madrid

The complexation of high-spin lanthanides to porphyrinoids is a powerful strategy for the development of advanced molecular *** this context,the use of expanded porphyrinoids remains elusive since their coordination chemistry is challenging to ***,taking inspiration from on-surface chemistry,we explored the coordination of Dy^(3+)to a six-membered porphyrinoid,namely,the hemihexaphyrazine ***,we observed the selective formation of a mono-nuclear off-centered,out-of-plane H_(2)Hhp-Dy^(3+)complex when performing the complexation under reductive *** this reaction,the oxidation state of the macrocycle did not *** X-ray diffraction analysis,we found that the coordination number of Dy in this complex was *** macrocycle cocrystallized with decamethylcobaltocene(Cp_(2)^(*)Co)molecules,giving rise to a wellordered solid-state packing,governed byπ-π*** a result of this organization,a small magnetic coupling between the neighboring molecules was *** in all,this work provides key insights into the coordination of magnetically active metals with expanded porphyrinoids,thus motivating the development of advanced spintronic devices.

关键词： porphyrins dysprosium macrocycle coordination chemistry magnetism

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Design of Biologically Active Macromolecular Ligands and Their Luminescent Complexes with Terbium Ions

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Chinese Journal of Polymer Science 2024年第5期42卷 604-611,I0007页

作者： Tatiana N.Nekrasova Andrei I.Fischer Natalia A.Nesterova Anatoliy V.Dobrodumov Anzhelika V.Garshinina Olga D.Shuvaeva Natalya V.Zakharova evgenii F.Panarin Institute of Macromolecular Compounds Russian Academy of Sciences31 Bolshoy pr.St Petersburg199004Russia Smorodintsev Research Institute of Influenza Russian Ministry of Health15/17 ul.prof.PopovaSt Petersburg197376Russia

Water-soluble copolymers of p-methacrylamidobenzoic acid(MABA)with neutral comonomers(N-vinylpyrrolidone(VP),N-methyl-N-vinylacetamide(MVAA),N-methacryloyl glucosamine(MAG))and anionic comononer sodium styrene sulfonate(NaSS)were synthesized by radical *** interactions between the prepared copolymers and Tb^(3+)ions in aqueous solutions were studied;the significant influence of chemical structure of a comonomer on luminescence intensity of Tb^(3+)complexes with the copolymers was *** luminescence intensity of Tb^(3+)complexes with the copolymers containing N-vinylamide units(VP,MVAA)is three times more intense than that observed for the complexes between Tb^(3+)and MAG-containing *** the case of NaSS-containing copolymers,the luminescence intensity is controlled by the values of binding constants between Tb^(3+)and MABA and the content of MABA units in a *** studied copolymers and their complexes with Tb^(3+)have low cytotoxicity and a pronounced antiviral activity against human respiratory syncytial virus.

关键词： Luminescence Water-soluble copolymers Lanthanide complexes Antiviral activity Cytotoxicity

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In vivo real-time monitoring delayed administration of M2 macrophages to enhance healing of tendon by NIR-II fluorescence imaging

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Nano Research 2024年第5期17卷 4379-4390页

作者： Yuzhou Chen Mo Chen Chengxuan Yu Huizhu Li Liman Sai Nguyen T.k.Thanh Yueming Wang Yan Wo Jian Zhang Xing Yang evgenii L.Guryev Andrei V.Zvyagin Hao De Min Tang Shiyi Chen Yunxia Li Yuefeng Hao Sijia Feng Jun Chen Sports Medicine Institute of Fudan University Department of Sports MedicineHuashan HospitalFudan UniversityShanghai 200040China Department of Orthopedic Surgery Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200092China Department of Bone and Joint Surgery Department of OrthopedicsRenji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200001China Department of Physics Shanghai Normal UniversityShanghai 200234China Biophysics Group Department of Physics and AstronomyUniversity College LondonLondon WC1E 6BTUK UCL Healthcare Biomagnetic and Nanomaterials Laboratories London W1S 4BSUK Department of Anatomy and Physiology School of MedicineShanghai Jiao Tong UniversityShanghai 200025China Department of Orthopedics Affiliated Suzhou Hospital of Nanjing Medical UniversitySuzhou 215500China Institute of Biology and Biomedicine Lobachevsky State University of Nizhny NovgorodNizhny Novgorod 603950Russia Mathematical Institute University of OxfordOxford OX26GGUK Institute of Natural Sciences School of MathematicsShanghai Jiao Tong UniversityShanghai 200240China

The administration time is a critical but long-neglected point in cell therapy based on macrophages because the incorrect time of macrophage administration could result in diverse outcomes regarding the same macrophage *** this work,the second near-infrared(NIR-II)fluorescence imaging in vivo tracking of M2 macrophages during a pro-healing therapy in the mice model of rotator cuff injury revealed that the behavior of administrated macrophages was influenced by the timing of their *** delayed cell therapy(DCT)group had a longer retention time of injected M2 macrophages in the repairing tissue than that in the immediate cell therapy(ICT)*** keller-Segel model and histological analysis further demonstrated that DCT altered the chemotaxis of M2 macrophages and improved the healing outcome of the repaired structure in comparison with *** results offer a possible explanation of previous conflicting results on reparative cell therapy and provoke reconsideration of the timing of these therapies.

关键词： macrophage cell therapy NIR-II in vivo imaging delayed therapy tendon healing

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GOx@Fe_(3)O_(4)-HNTs微囊反应器的构筑及多酶级联催化性能

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高等学校化学学报 2024年第1期45卷 72-83页

作者：黄雨晴刘妍张宏丽林森孙仕勇 golubev Evgeny 吕瑞 kOTOVA Olga kOTOVA Elena 西南科技大学环境与资源学院固体废物处理与资源化教育部重点实验室绵阳621010 西南科技大学非金属矿产地质及其开发利用四川省高等学校重点实验室绵阳621010 俄罗斯科学院乌拉尔分院科米科学中心地质研究所瑟克特夫卡尔167982俄罗斯圣彼得堡国立矿业大学圣彼得堡199106俄罗斯

细胞内或细胞间的微空间使得生物体内的各种酶促反应能够高效有序地进行.基于此,本文结合天然酶-纳米酶二者的优势,构筑了一种模拟体内酶促级联反应的微囊反应器.首先,以天然硅铝酸盐矿物埃洛石纳米管(HNTs)为载体,在其表面原位生成具... 详细信息

细胞内或细胞间的微空间使得生物体内的各种酶促反应能够高效有序地进行.基于此,本文结合天然酶-纳米酶二者的优势,构筑了一种模拟体内酶促级联反应的微囊反应器.首先,以天然硅铝酸盐矿物埃洛石纳米管(HNTs)为载体,在其表面原位生成具有类辣根过氧化物酶活性的四氧化三铁(Fe3O4);随后,将其作为囊壁材料封装天然葡萄糖氧化酶(GOx),构筑GOx@Fe3O4-HNTs微囊反应器.当向体系中加入葡萄糖时,微囊反应器内的GOx先将葡萄糖转化为葡萄糖酸和过氧化氢(H_(2)O_(2)),之后H_(2)O_(2)继续被囊壁中的Fe_(3)O_(4)催化转化为羟基自由基,触发底物3,3',5,5'-四甲基联苯胺(TMB)显色.其中,Fe_(3)O_(4)-HNTs作为囊壁材料不仅使囊内GOx免受外界环境干扰,还可与GOx构建级联催化反应体系,这种酶-纳米酶微囊化级联体系具有比天然酶系统更优异的催化性能和反应稳定性.此外,因磁性Fe_(3)O_(4)的参与,材料还具有可回收性和重复使用性.这种酶-纳米酶复合微囊反应器为模拟生物体内限域环境下的多酶反应体系提供了新方法,同时为后续生物分析与仿生催化领域的进一步研究奠定了基础.

关键词：纳米酶微囊反应器埃洛石纳米管葡萄糖氧化酶级联反应

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The effect of long-term application of nitrogen-rich fertilizers on soil resistome:A study of conventional and organic cropping systems

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Soil Ecology Letters 2024年第3期6卷 135-150页

作者： Alexey S.Vasilchenko evgenii O.Burlakov Darya V.Poshvina Denis S.Gruzdev Sergey V.kravchenko Aleksandr V.Iashnikov Ning Ling Anastasia V.Vasilchenko Laboratory of Antimicrobial Resistance Institute of Environmental and Agricultural Biology(X-BIO)Tyumen State UniversityTyumenRussia Research Institute of Mathematics Physics and Computer ScienceDerzhavin Tambov State UniversityTambovRussia International Integrated Research Laboratory for Climate Change Land Use and BiodiversityInstitute of Environmental and Agricultural Biology(X-BIO)Tyumen State UniversityTyumenRussia SciBear OU Tartu Mnt 67/1-13bKesklinna Linnaosa10115 TallinnEstonia Center for Grassland Microbiome State Key Laboratory of Grassland Agro-EcosystemsCollege of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhou 730000China

Metagenomic studies of various soil environments have previously revealed the widespread distribution of antibiotic resistance genes(ARGs)around the *** this study,we applied shotgun metagenomics to investigate differences in microbial communities and resistomes in Chernozem soils that have been under long-term organic and conventional cropping *** organic cropping system was seeded with Triticum spelta without any *** conventional cropping system was seeded with Tríticum durum Desf and used mineral fertilizer(NPk),that resulted in an increased amount of total and available carbon and nitrogen in *** all samples,we identified a total of 21 ARG classes,among which the dominant were vancomycin,tetracycline and *** of soil microbial communities revealed differences between the studied fields in the relative abundances of 14 and 53 genera in topsoil and subsoil,*** analysis showed significant correlations(positive and negative)among 18 genera and 6 ARGs,as well as between these ARGs and some chemical properties of *** analysis of metagenome-assembled genomes revealed that Nitrospirota,Thermoproteota,Actinobacteriota and Binatota phyla of archaea and bacteria serve as hosts for glycopeptide and fluoroquinolone/tetracycline ***,the data obtained enrich knowledge about the consequences of human agricultural activities in terms of soil microbiome modification and highlight the role of nitrogen cycling taxa,including uncultivated genera,in the formation of soil resistome.

关键词： soil microbiome inorganic fertilizer nitrogen cycle uncultured bacteria chemolithotrophs Binatia

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Aqueous-phase reforming of hydroxyacetone solution to bio-based H_(2)over supported Pt catalysts

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Green Energy & Environment 2024年第4期9卷 777-788页

作者： A.k.k.Vikla k.koichumanova Songbo He k.Seshan Joint International Research Laboratory of Circular Carbon Nanjing Tech UniversityNanjing211816China Faculty of Science and Technology University of Twente7500 AE EnschedeThe Netherlands CoRe Pro 9723 BL GroningenThe Netherlands

Aqueous-phase reforming(APR)is an attractive process to produce bio-based hydrogen from waste biomass streams,during which the catalyst stability is often challenged due to the harsh reaction *** this work,three Pt-based catalysts supported on C,AlO(OH),and ZrO_(2)were investigated for the APR of hydroxyacetone solution in afixed bed reactor at 225℃and 35 *** them,the Pt/C catalyst showed the highest turnover frequency for H_(2)production(TOF of 8.9 molH_(2)molPt^(-1)min^(-1))and the longest catalyst *** the AlO(OH)and ZrO_(2)supported Pt catalysts,the side reactions consuming H_(2),formation of coke,and Pt sintering result in a low H_(2)production and the fast catalyst *** proposed reaction pathways suggest that a promising APR catalyst should reform all oxygenates in the aqueous phase,minimize the hydrogenation of the oxygenates,maximize the WGS reaction,and inhibit the condensation and coking reactions for maximizing the hydrogen yield and a stable catalytic performance.

关键词： APR Hydroxyacetone TOF Bio-based H_(2) Support effect

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