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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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Oligodendroctyes:the forgotten players of diabetes pathophysiology

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Neural Regeneration Research 2024年第11期19卷 2349-2350页

作者： Juan Antonio López-Villodres Beatriz García-díaz departamento fisiología Humana Histología HumanaAnatomía Patológica y Educación Física y DeportivaFacultad de MedicinaUniversidad de MálagaMálagaSpain UGC Neurociencia.Instituto de Investigación Biomédica de Málaga y Plataforma en Nanomedicina(IBIMA Plataforma Bionand) MálagaSpain

Oligodendrocytes(OLs),glial cells that provide myelin sheaths to axons in the central nervous system(CNS),have a dual ***,this myelin fatty cover around the axons protects the nerves and is crucial for the saltatory propagation of action *** and not less important,OLs provide trophic support to neurons and ***,OL metabolism is important for OL well-being and the proper accomplishment of their functions,and OL metabolism energetics directly affect the energy metabolism of neighboring neurons.

关键词： metabolism nerves myelin

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Relationship of Corrosion Behavior Between Single-Phase Equiatomic CoCrNi,CoCrNife,CoCrNifeMn Alloys and Their Constituents in NaCl Solution

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Acta Metallurgica Sinica(English Letters) 2021年第11期34卷 1574-1584页

作者： d.P.wang J.w.Shen Z.Chen f.G.Chen P.Y.Guo Y.x.Geng Y.x.wang School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

The composition is a significant issue for corrosion resistance of metallic *** reveal the correlation of corrosion behavior between multiprinciple alloys and their constituents,a series of single-phase equiatomic alloys of CoCrNi,CoCrNife and CoCrNifeMn was *** electrochemical and scanning electron microscope results demonstrated that corrosion resistance of the equiatomic alloys in 0.1 M NaCl solution is located in the range but not the average value of their constituents.x-ray photoelectron spectroscopy analysis indicated that the protective performance of passive film is mainly determined by the constituent with the highest corrosion resistance and the breakdown of passive film is mainly dominated by the elements with the highest corrosion *** findings can guide the materials design of multiprinciple alloys with expected corrosion performance.

关键词： High-entropy alloy Corrosion Constituent x-ray photoelectron spectroscopy(xPS) Passive films

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Adsorption of pharmaceutical pollutants on ZnCl_(2)-activated biochar from corn cob:Efficiency,selectivity and mechanism

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Journal of Bioresources and Bioproducts 2024年第1期9卷 58-73页

作者： Christian f.Varela L.C.Moreno-Aldana Yazmin Yaneth Agámez-Pertuz department of Chemistry National University of ColombiaAv.Carrera 30 No.45-03BogotáD.C.Colombia department of Biology and Chemistry University of the Llanoskm 12 road to Puerto LópezVillavicencioColombia

The occurrence of pharmaceuticals in water bodies and drinking water poses risks for the envi-ronment and human health,thus it is necessary to study methodologies that allow the efficient removal of these *** this work,corn cob-derived biochar was obtained by ZnCl_(2)-activation,and subsequent carbonization at 700℃.The effect of contact time,temperature,pH,and initial concentration on the adsorption capacity of acetaminophen(ACE)and amoxicillin(AMx)was determined through batch *** addition,the kinetics,isotherms,and ther-modynamics parameters were *** activated biochar exhibited a maximum adsorp-tion capacity of 332.08 mg/g for ACE and 175.86 mg/g for *** adsorption kinetics and adsorption isotherm of ACE corresponded to the pseudo-second order and Langmuir model,***,pseudo-first-order kinetics and the freundlich isotherm model were well-fitted to AMx *** ACE and AMx co-adsorption had a synergistic effect on AMx but an antagonistic effect on ACE removal,achieving a maximum adsorption capacity of 193.51 and 184.58 mg/g,*** the other hand,fixed-bed column experiments showed that the adsorption capacity depends on the influent concentration,and the breakthrough curve fits the Thomas and Yoon-Nelson *** mechanism adsorption studies showed that surface inter-actions(hydrogen bonding formation and n-𝜋interactions)are the main driving forces for the adsorption process,and pore filling is the rate-limiting *** this way,the prepared biochar exhibits a high potential for the adsorption of pharmaceutical compounds from water.

关键词： Biochar Adsorption Acetaminophen Amoxicillin wastewater treatment

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Magnetic, Photoluminescent and Semiconductive Properties of a Novel 4f-5d Bromide Compound(La6Hg5Br26)[4(HgBr2)](2Br)

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Chinese Journal of Structural Chemistry 2020年第1期39卷 154-163,5页

作者： LIN wei-sheng CHEN wen-Tong department of Ecological and Resources Engineering Fujian Key Laboratory of Eco-industrial Green TechnologyWuyi UniversityWuyishan 354300China Institute of Applied Chemistry School of Chemistry and Chemical EngineeringJiangxi Province Key Laboratory of CoordinationChemistryJinggangshan UniversityJi’an 343009China State Key Laboratory of Structural Chemistry Fujian Institute of Researchon the Structure of MatterChinese Academy of SciencesFuzhou 350002China

An unprecedented 4f-5d material(La6Hg5Br26)[4(HgBr2)](2Br)(1)was syn-thesized by hydrothermal reactions and structurally characterized by single-crystal x-ray diffraction *** 1 crystallizes in the Pbam space group of orthorhombic system with a=13.0980(10),b=13.6650(9),c=28.010(2)?,V=5013.4(6)?^3,Br36Hg9La6,Mr=5515.53,Z=2,dc=3.613 g/cm^3,μ(MoKα)=29.457 mm^–1 and f(000)=*** 1 is characteristic of a two-dimensional(2d)layered *** photoluminescent measurements with solid-state samples reveal that compound 1 has a strong emission in the green region of light *** has remarkable CIE chromaticity coordinates of(0.2499,0.3589).A wide optical band gap of 3.41 eV is discovered by the solid-state UV/vis diffuse reflectance *** variable-temperature magnetic susceptibility obeys the Curie-weiss law(cm=c/(T–q))with C=2.48 K and a negative weiss constantθ=–169.07 K as revealed by the magnetic measurements,indicating the existence of an antiferromagnetic interaction in compound 1.

关键词： lanthanide mercury magnetism photoluminescence semiconductor

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Molecular dynamics Simulation of Porous Layer-enhanced dislocation Emission and Crack Propagation in Iron Crystal

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Journal of Materials Science & Technology 2011年第11期27卷 1025-1028页

作者： d. Li f.Y. Meng x.Q. Ma L.J. Qiao w.Y. Chu department of Physics University of Science and Technology Beijing Beijing 100083 China Corrosion and Protection Center Key Lab of Environmental Fracture （Ministry of Education） University of Science and Technology Beijing Beijing 100083 China

The internal stress induced by a porous layer or passive layer can assist the applied stress to promote dislocation emission and crack propagation, e.9. when the pipeline steel is buried in the soil containing water, resulting in stress corrosion cracking （SCC）. Molecular dynamics （Md） simulation is performed to study the process of dislocation emission and crack propagation in a slab of fe crystal with and without a porous layer on the surface of the crack. The results show that when there is a porous layer on the surface of the crack, the tensile stress induced by the porous layer can superimpose on the external applied stress and then assist the applied stress to initiate crack tip dislocation emission under lowered stress intensity KI, or stress. To respond to the corrosion accelerated dislocation emission and motion, the crack begins to propagate under lowered stress intensity KI, resulting in SCC.

关键词： Molecular dynamics simulation dislocation emission Crack propagation Porouslayer Stress intensity

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AI for organic and polymer synthesis

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Science China Chemistry 2024年第8期67卷 2461-2496页

作者： xin Hong Qi Yang Kuangbiao Liao Jianfeng Pei Mao Chen fanyang Mo Hua Lu wen-Bin Zhang Haisen Zhou Jiaxiao Chen Lebin Su shuo-Qing Zhang Siyuan Liu xu Huang Yi-Zhou Sun Yuxiang wang Zexi Zhang Zhunzhun Yu Sanzhong Luo xue-feng fu shu-Li You Center of Chemistry for frontier Technologies Department of ChemistryZhejiang UniversityHangzhou 310027China Center of Basic Molecular Science Department of ChemistryTsinghua UniversityBeijing 100084China Guangzhou National Laboratory Guangzhou 510005China Center for Quantitative Biology Academy for Advanced Interdisciplinary StudiesPeking UniversityBeijing 100871China State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200433China School of Materials Science and Engineering Peking UniversityBeijing 100871China Beijing National Laboratory for Molecular Sciences Center for Soft Matter Science and EngineeringKey Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China AI for Science(AI4S)-Preferred Program Shenzhen Graduate SchoolPeking UniversityShenzhen 518055China State Key Laboratory of Chemical Biology Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032China department of Chemical Sciences National Natural Science Foundation of ChinaBeijing 100085China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

Recent years have witnessed the transformative impact from the integration of artificial intelligence with organic and polymer synthesis. This synergy offers innovative and intelligent solutions to a range of classic problems in synthetic chemistry. These exciting advancements include the prediction of molecular property, multi-step retrosynthetic pathway planning, elucidation of the structure-performance relationship of single-step transformation, establishment of the quantitative linkage between polymer structures and their functions, design and optimization of polymerization process, prediction of the structure and sequence of biological macromolecules, as well as automated and intelligent synthesis platforms. Chemists can now explore synthetic chemistry with unprecedented precision and efficiency, creating novel reactions, catalysts, and polymer materials under the datadriven paradigm. despite these thrilling developments, the field of artificial intelligence(AI) synthetic chemistry is still in its infancy, facing challenges and limitations in terms of data openness, model interpretability, as well as software and hardware support. This review aims to provide an overview of the current progress, key challenges, and future development suggestions in the interdisciplinary field between AI and synthetic chemistry. It is hoped that this overview will offer readers a comprehensive understanding of this emerging field, inspiring and promoting further scientific research and development.

关键词： organic synthesis polymer synthesis machine learning prediction chemical database automated synthesis

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Morphology Control and Optical Absorption Properties of Ag Nanoparticles by Ion Implantation

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Journal of Materials Science & Technology 2009年第5期25卷 669-672页

作者： G.x. Cai f. Ren x.H. xiao L.x. fan x.d. Zhou C.Z. Jiang Key Laboratory of Acoustic and Photonie Materials and devices of Ministry of Education Wuhan University Wuhan 430072 China

Ion implantation is a powerful method for fabricating nanoparticles in dielectric. for the actual application of nanoparticle composites, a careful control of nanoparticles has to be achieved. In this letter, the size, distribution and morphology of Ag nanoparticles are controlled by controlling the ion current density, ion implantation sequence and ion irradiation dose. Single layer Ag nanoparticles are formed by Ag^＋ ion implantation at current density of 2.5 μ^A/cm2. By Ag and Cu ions sequential implantation, the size of single layer Ag nanoparticles increases. while, by Cu and Ag ions sequential implantation, uniform Ag nanoparticles with wide distribution are formed. The morphology of Ag nanoparticles changes to hollow and sandwiched nanoparticles by Cu^＋ ion irradiation to doses of 3×10^16 and 5×10^16 ions/cm^2. The optical absorption properties of Ag nanoparticles are also tailored by these ways.

关键词： Nanoparticles Ion implantation Transmission electron microscopy

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Auxin as a Model for the Integration of Hormonal Signal Processing and Transduction

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Molecular Plant 2008年第2期1卷 229-237页

作者： w.d. Teale f.A. ditengou A.d. dovzhenko x. Li A.M. Molendijk B. Ruperti I. Paponov K. Palme Institute of Biology Ⅱ Faculty of Biology University of Freiburg D-79104 Freiburg Germanya dipartimento di Agronomia Ambientale e Produzioni Vegetali Agripolis University of Padova viale dell'Universita 16 35020 Legnaro Italy

The regulation of plant growth responds to many stimuli. These responses allow environmental adaptation, thereby increasing fitness. In many cases, the relay of information about a plant＇s environment is through plant hormones. These messengers integrate environmental information into developmental pathways to determine plant shape. This re- view will use, as an example, auxin in the root ofArabidopsis thaliana to illustrate the complex nature of hormonal signal processing and transduction. It will then make the case that the application of a systems-biology approach is necessary, if the relationship between a plant＇s environment and its growth/developmental responses is to be properly understood.

关键词： Auxin as a Model Integration Processing and Transduction

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OH+HCl→Cl+H_(2)O反应中的反应物转动激发效应

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Chinese Journal of Chemical Physics 2024年第2期37卷 211-220,I0102页

作者：徐昕陈俊刘舒张东辉中国科学院大连化学物理研究所分子反应动力学国家重点实验室大连116023 中国科学院大学北京100049 中国科学院福建物质结构研究所结构化学国家重点实验室福州350002

本文在最近构建的f12a势能面上,对OH+HCl→Cl+H_(2)O的一系列反应物转动激发态进行了势能平均的五维含时波包计算,得到了初始态选择的反应几率和速率常数。研究发现,除了很低碰撞能量,单独激发反应物HCl到j_(1)=2或者OH到j_(2)=1得到了... 详细信息

本文在最近构建的f12a势能面上,对OH+HCl→Cl+H_(2)O的一系列反应物转动激发态进行了势能平均的五维含时波包计算,得到了初始态选择的反应几率和速率常数。研究发现,除了很低碰撞能量,单独激发反应物HCl到j_(1)=2或者OH到j_(2)=1得到了总反应几率的最大值.在低能区域,随着OH转动激发的增加,反应几率的共振增强迅速减小,导致250K以下的速率常数迅速下降HCl和OH同时转动激发的速率常数不是单独激发结果的简单叠加。最后,通过对(5,5)态以下初始转动态的速率常数进行玻尔兹曼平均,得到了反应的热速率常数,与实验结果基本吻合。

关键词：反应物转动激发含时波包反应几率 feshbach共振速率常数

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