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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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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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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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Porphyrins,phthalocyanines,and related covalent-organic frameworks in the photochemical and electrochemical water splitting:A review

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Particuology 2024年第7期90卷 236-265页

作者： Oxana V.Kharissova Yolanda Peña méndez boris I.Kharisov Aleksandr LNikolaev Edith Luévano-Hipólito Lucy T.González Universidad Autónoma de Nuevo León Ave.Universidad s/nSan Nicolás de los GarzaNuevo León66455Mexico Department of Chemistry Moscow State UniversityVorobievy HillsMoscowRussia CONACYT-Universidad Autónoma de Nuevo León Facultad de Ingeniería Civil-Departamento de Ecomateriales y EnergíaCd.UniversitariaC.P.66455San Nicolás de los GarzaNLMexico Tecnologico de monterrey Escuela de Ingeniería y CienciasMonterreyNuevo León 64890Mexico Tecnologico de monterrey Centro del AguaMonterreyNuevo León 64890Mexico

In this review,the possibilities of photochemical and electrochemical water splitting(WS)using porphyrins,phthalocyanines,related macrocycles,and their metal complexes are *** efforts are being carried out in order to develop novel and cheap methods for water decomposition to generate inexhaustible greener energy sources(molecular hydrogen)instead of oil and *** processes of WS in heterogeneous and homogeneous media require novel photo-and electrocatalysts,in particular those on macrocycle basis.A high WS efficiency has been observed for porphyrins and phthalocyanines,showing their suitability both for HER and OER processes are available using these relative compounds for WS *** can be used in photocatalytic and electrocatalytic WS processes both in their free forms or as metal porphyrins/porphyrinates,mainly loaded on various inorganic materials,such as Au NPs,C_(3)N_(4),GaP,KTaO_(3),GaP,and so on,as part of porphyrin-containing polymers or on electrode surface as modifying coatings,being sometimes better than commercial catalysts,such as Pt/*** H2 evolution can be considerably depended on the shape of porphyrin particles;in particular,porphyrin nanowires can yield up to 20 times more H2 than its *** certain cases,both HER and OER can be driven in the same electrolyte using metal *** capacity of metal porphyrins to generate ROS(in particular,singlet oxygen 1O_(2))under ultrasonic treatment is known and can be successfully used for H_(2)O_(2) and O_(2) *** can be used in similar processes in free form or as composites with inorganic or organic counterparts,being immobilized on nanocarbons,metal oxides and salts,or simply dissolved in water acting in a homogeneous *** additional use of ultrasound can lead to better results due to the synergistic effect of the sonochemical treatment and ***-organic frameworks are also applied for WS purposes and are mainly based

关键词： Porphyrins Phthalocyanines COFs Water splitting Photocatalysis Electrocatalysis

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Two-dimensional anisotropic vortex quantum droplets in dipolar Bose−Einstein condensates

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Frontiers of physics 2024年第2期19卷 205-211页

作者： Guilong Li Xunda Jiang Bin Liu Zhaopin Chen boris A.malomed Yongyao Li School of Physics and Optoelectronic Engineering Foshan UniversityFoshan 528225China Physics Department and Solid-State Institute TechnionHaifa 32000Israel Department of Physical Electronics School of Electrical EngineeringFaculty of EngineeringTel Aviv UniversityTel Aviv 69978Israel Instituto de Alta Investigación Universidad de TarapacáCasilla 7DAricaChile Guangdong-Hong Kong-macao Joint Laboratory for Intelligent micro−Nano Optoelectronic Technology Foshan UniversityFoshan 528225China

Creation of stable intrinsically anisotropic self-bound states with embedded vorticity is a challenging ***,no such states in Bose−Einstein condensates(BECs)or other physical settings were *** BEC suggests a unique possibility to predict stable two dimensional anisotropic vortex quantum droplets(2D-AVQDs).We demonstrate that they can be created with the vortex axis oriented perpendicular to the polarization of *** stability area and characteristics of the 2D-AVQDs in the parameter space are revealed by means of analytical and numerical ***,the rotation of the polarizing magnetic field is considered,and the largest angular velocities,up to which spinning 2D-AVQDs can follow the rotation in clockwise and anti-clockwise directions,are *** between moving 2D-AVQDs are studied too,demonstrating formation of bound states with a vortex−antivortex−vortex structure.A stability domain for such stationary bound states is *** dipolar states,that can be readily implemented by means of phase imprinting,quickly transform into robust 2D-AVQDs,which suggests a straightforward possibility for the creation of these states in the experiment.

关键词： dipolar Bose−Einstein condensate anisotropic vortex quantum droplets

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Hydroxyapatite composites with carbon allotropes:Preparation,properties,and applications

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Particuology 2024年第5期88卷 239-265页

作者： boris I.Kharisov Oxana V.Kharissova Lucy T.González Yolanda Peña méndez Igor E.Uflyand Idalia Gómez de la Fuente Universidad Autónoma de Nuevo León Ave.UniversidadCiudad UniversitariaSan Nicolás de los GarzaNuevo León 66455Mexico Tecnologico de monterrey Escuela de Ingeniería y CienciasMonterreyNuevo Leon 64890Mexico Department of Chemistry Southern Federal UniversityRostov-on-DonRussia

Hydroxyapatite(HA)and its composites with inorganic additives,dopants,and polymers is a rapidly developing branch in the materials *** particular,carbon allotropes are widely used in these composites being widely applied for medical *** a gap of insufficient generalization of recent achievements in the field of the HA/Carbon composites,in this review we present the state of the art of the field of HA composites and hybrids with classic carbon allotropes and *** composites are known for carbon nanotubes,nanofibers,graphene and its oxidized forms,as well as,in a lesser grade,for graphite,fullerenes,nanodiamonds,carbon nanofoams,*** composites can be fabricated by a variety of classic and less-common methods,such as co-precipitation(with or without ultrasonic treatment),CVD,hot isostatic pressing,hydrothermal,spark plasma sintering,biomimetic mineralization,thermal and plasma spray,electrochemical and electrophoretic deposition,self-assembling,3D printing,electrospinning,and lyophilisation,among *** of various synthesis techniques can be also carried out for composite *** or synthetic HA can be used as it is for further interaction with carbon allotropes or it can be first prepared and then reacted with carbon counterpart;similarly,carbon allotropes can be introduced into the interaction with HA directly or they can be first synthesized,in particular from *** biocompatible composites can be produced in the form of coatings,powders,and scaffolds and can additionally contain quantitative amounts of third phases,frequently natural or synthetic *** these composites,especially with O-containing functionalizing groups,HA disadvantages could be considerably decreased with simultaneous enhancement of mechanical properties,becoming similar to human bone,chemical stability and biocompatibility,as well as possessing antibacterial ***→G reduction and higher HA decoration were obs

关键词： Hydroxyapatite Carbon nanotubes Graphene Quantum dots Fullerenes Nanodiamonds

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Human Eosinophil Cell manipulation by Optical Tweezers

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Open Journal of Biophysics 2024年第3期14卷 330-338页

作者： Pavel Yale Jean michel Edoukoua Konin Abadê Ange-boris N’guessan michel Abaka Kouacou Jérémie T. Zoueu Laboratoire dInstrumentation Image et Spectroscopie (L2IS) Institut National Polytechnique Houphout-Boigny (INPHB) Yamoussoukro Cte dIvoire Laboratoire de Chimie et de Physique Appliques Sciences et Techniques Universit Alassane Ouattara Bouak Cte dIvoire

In this work, lateral deformation of human eosinophil cell during the lateral indentation by an optically trapped microbead of diameter 4.5 µm is studied. The images were captured using a CCD camera and the Boltzmann statistics method was used for force calibration. Using the Hertz model, we calculated and compared the elastic moduli resulting from the lateral force, showing that the differences are important and the force should be considered. Besides the lateral component, the setup also allows us to examine the lateral cell-bead interaction. The mean values of the properties obtained, in particular the elastic stiffness and the shear stiffness, were Eh = (37.76 ± 2.85) µN/m and Gh = (12.57 ± 0.32) µN/m. These results show that the lateral indentation can therefore be used as a routine method for cell study, because it enabled us to manipulate the cell without contact with the laser.

关键词： Optical Tweezers Human Eosinophil Cell Indentation Shear Stiffness

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mechanism of the Initial Stage of Thermal Decomposition of Nitroguanidine

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火炸药学报 2023年第1期46卷 31-40页

作者： boris E.Krisyuk Danila A.markin Timofey m.Sypko Viktor V.Zakharov Nikita V.Chukanov boris L.Korsunskiy Federal Research Center of Problems of Chemical Physics and medicinal Chemistry Russian Academy of Sciences142432prosp.Academician Semenov1ChernogolovkaMoscow RegionRussia Plekhanov Russian University of Economics Department of Chemistry and Physics36 Stremyanny laneMoscow 117997Russia Lomonosov moscow State University Faculty of Fundamental Physical and Chemical engineeringGSP-11 Leninskie Goryp.51Moscow 119991Russia N.N.Semenov Federal Research Center for Chemical Physics Russian Academy of Science 4 Kosygina StreetBuilding 1Moscow 119991Russia

A theoretical and experimental study of the thermal decomposition of nitroguanidine(NQ) has been carried out. Various thermolysis channels were studied by quantum chemistry methods at the CCSD(or DLPNO-CCSD) level using the aug-cc-pVDZ basis set. It is shown that the lowest activation enthalpies(170-180kJ/mol) are characteristic of the reactions of NO2abstraction from the initial NQ and the reaction channel with the transfer of oxygen from the nitro group to carbon in the limiting stage. Additionally, the thermolysis of NQ was studied experimentally in a nonisothermal mode with heating rates from 1 to 10K/min. In these experiments, the weight loss of the sample, thermal effects, and mass spectra of the products were recorded. An analysis of the experimental data confirmed the results of a theoretical study of the mechanism of thermal decomposition of NQ. The main thermolysis products are N2O, HNCO, NH3, and NO2, which fully corresponds to quantum chemical calculations.

关键词： primary thermolysis steps quantum-chemical calculation mass spectrometry DSC TG

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Adaptation to a novel host and performance trade-off in host-generalist and host-specific insect ectoparasites

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Insect Science 2022年第2期29卷 567-580页

作者： Irina S.Khokhlova Luther van der mescht Elizabeth m.Warburton Nadezhda A.Stavtseva boris R.Krasnov Wyler Department of Dryland Agriculture French Associates Institute for Agriculture and Biotechnology of DrylandsJacob Blaustein Institutes for Desert ResearchBen-Gurion University of the NegevSede Boqer CampusMidreshet Ben-GurionIsrael mitrani Department of Desert Ecology Swiss Institute for Dryland Environmental and Energy ResearchJacob Blaustein Institutes for Desert ResearchBen-Gurion University of the NegevSede Boqer CampusMidreshet Ben-GurionIsrael Clinvet International Center for the Ecology of Infectious Diseases Odum School of EcologyUniversity of Georgia

We investigated the performance trade-offs of fleas(Siphonaptera)while adapting to a novel host using two host generalists(Xenopsylla conformis and Xenopsylla ramesis)and one host specialist(Parapulex chephrenis)maintained on their principal hosts(meriones crassus for Xenopsylla and Acomys cahirinus for ***).We asked whether,over generations,(i)a host generalist may become a specialist by evolving the ability to exploit a novel host and losing the ability to exploit an original host and(ii)a host specialist can become a generalist by evolving the ability to exploit a novel host without losing the ability to exploit an original *** established an experimental line of each species on a novel host(Acomys russatus for Xenopsylla and *** for ***)and maintained this line on this host during 23 *** compared reproductive performance of progenitors of each line and their descendants when they exploited either original or novel host in terms of egg number and size,hatching success,offspring production,and offspring *** found changes in performance over generations in female offspring size *** conformis demonstrated a tendency to become a host specialist(increased performance on the novel host with a concomitant decreased performance on the original host),whereas *** demonstrated a tendency to become a host generalist(increased performance on the novel host without a concomitant decreased performance on the original host).We conclude that the probability of generalist to specialist transition,and vice versa,is context-dependent and varies between species.

关键词： experimental evolution fleas generalist performance rodents specialist

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Surface-enhanced Raman scattering inside Au@Ag core/shell nanorods

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Nano Research 2016年第8期9卷 2303-2318页

作者： boris Khlebtsov Institute of Biochemistry and Physiology of Plants and microorganisms Russian Academy of Sciences Saratov 410049 Russia Saratov National Research State University Saratov 410012 Russia

The design and synthesis of plasmonic nanoparticles with Raman-active molecules embedded inside them are of significant interest for sensing and imaging applications. However, direct synthesis of such nanostructures with controllable shape, size, and plasmonic properties remains extremely challenging. Here we report on the preparation of uniform Au@Ag core/sheU nanorods with controllable Ag shells of 1 to 25 nm in thickness. 1,4-Aminothiophenol （4-ATP） molecules, used as the Raman reporters, were located between the Au core and the Ag shell. Successful embedding of reporter molecules inside the core/shell nanoparticles was confirmed by the absence of selective oxidation of the amino groups, as measured by Raman spectroscopy. The dependence of Raman intensity on the location of the reporter molecules in the inside and outside of the nanorods was studied. The molecules in the interior showed strong and uniform Raman intensity, at least an order of magnitude higher than that of the molecules on the nanoparticle surface. In contrast to the usual surface-functionalized Raman tags, aggregation and clustering of nanoparticles with embedded molecules decreased the surface-enhanced Raman scattering （SERS） signal. The findings from this study provide the basis for a novel detection technique of low analyte concentration utilizing the high SERS response of molecules inside the core/shell metal nanostructures. As an example, we show robust SERS detection of thiram fungicide as low as 10-9 m in solutions.

关键词： surface-enhanced Ramanscattering (SERS) Au@Ag nanorods nanocuboids multipole plasmons

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