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High Temperature Iron Ethylene Polymerization Catalysts Bearing N,N,N'-2-(1-(2,4-Dibenzhydryl-6-fluorophenylimino)ethyl)-6-(1-(arylphenylimino)ethyl)pyridines

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Chinese Journal of Polymer Science 2024年第2期42卷 188-201,I0007页

作者： Chantsalnyam Bariashir Qiu-Yue Zhang Bayasgalan Ulambayar Gregory A.Solan Tong-Ling Liang wen-hua sun Institute of Chemistry and Chemical Technology Mongolian Academy of SciencesUlaanbaatar13330Mongolia Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing100190China Department of Chemistry University of LeicesterUniversity RoadLeicesterLE17RHUK State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China

The N,N,N'-ferrous chloride complexes,[2-{CMeN(2,4-(CHPh)_(2)-6-FC_(6)H_(2))}-6-(CMeNAr)C_(5)H_(3)N]FeCl_(2)(Ar=2,6-Me_(2)C_(6)H_(3) Fe1,2,6-Et_(2)C_(6)H_(3)Fe2,2,6-^(i)Pr_(2)C_(6)H_(3) Fe3,2,4,6-Me_(3)C_(6)H_(2) Fe4 and 2,6-Et_(2)-4-MeC_(6)H_(2) Fe5),each possessing one N-2,4-dibenzhydryl-6-fluorophenyl group,were readily synthesized from their respective unsymmetrical bis(imino)pyridines,*** identification of Fe2 highlighted the variation in the steric properties provided by the dissimilar N-aryl *** pre-treatment with either MAO or MMAO,complexes Fe1-Fe5 all displayed,at an operating temperature of 80℃,high activities for ethylene polymerization with levels falling in the order:Fe4> Fe1> Fe5> Fe2> ***,Fe4/MAO displayed the highest activity of 1.94×10^(7) g_(PE)·mol_(Fe)^(-1)·h^(-1) of the study with only a modest loss in performance at 90℃.Generally,the resulting polyethylenes were highly linear(T_(m) range:122-132℃),narrowly disperse and of low molecular weight(M_(w) range:6.73-46.04kg·mol^(-1)),with the most sterically hindered Fe3 forming the highest molecular weight polymer of the ***-group analysis by ^(1)H-and ^(13)CNMR spectroscopy revealed saturated alkyl(n-propyl and i-propyl) and unsaturated vinyl chain ends indicative of the role of both β-H elimination and chain transfer to aluminum as termination *** comparison with previou sly reported iron precatalysts with similar tridentate ligand skeletons,it is evident that the introduction of a large benzhydryl group in combination with a fluorine as the ortho-substituents of one N-aryl group has the effect of enhancing thermal stability of the iron polymerization catalyst whilst maintaining appreciable polymer molecular weight.

关键词： Iron catalyst Ethylene polymerization Linear polyethylene Fluoride effect Thermal stability

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High-Performanceα-Diimine Nickel Complexes for Facile Access of PE Elastomers with Exceptional Material Properties

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Chinese Journal of Polymer Science 2024年第5期42卷 620-635,I0008页

作者： Li-Dong Qin Xin-Yu Wang Qaiser Mahmood Zhi-Xin Yu Yi-Zhou Wang Song Zou Tong-Ling Liang wen-hua sun School of Pharmaceutical Sciences Changchun University of Chinese MedicineChangchun130117China Chemistry and Chemical Engineering Guangdong Laboratory Shantou515031China Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing100190China

For practicable elastomeric polyethylene,achieving high catalyst thermal stability and activity,along with precise control of polymer properties such as branching density,molecular weights,and distribution,is crucial but *** this study,two sets of symmetricalα-diimine nickel complexes,each comprising four nickel bromide or chloride complexes,were synthesized and investigated their performance for ethylene polymerization under various reaction *** activation with either Et2AlCl or MMAO cocatalysts,these complexes displayed not only high activity but also generated high molecular weight polyethylenes with controlled polydispersity and a substantial number of *** catalyst with the least steric hindrance displayed the remarkable high activity(up to 1.2×10^(7) g·mol^(-1)·h^(-1)).Notably,nickel bromides demonstrated higher activity compared to their chloride *** investigation into the effect of reaction temperature on catalytic performance revealed that NiBrMe-MMAO system displayed high thermal stability(activity up to 2.51×10^(6) g·mol^(-1)·h^(-1) at 100℃)and consistently yielded high polymer molecular weights with narrow polydispersity over a broad temperature range of 30-100℃.Of significant note,mechanical analysis of the resulting polyethylene demonstrated excellent ultimate tensile strength and high strain at ***,the polyethylene sample prepared at 100℃exhibited ultimate tensile strength up to 10 MPa with 1863%maximum strain at break and a strain recovery of up to 54.9%after ten cycles at a fixed strain of 300%,indicating excellent material properties of prepared thermoplastic polyethylene elastomers(TPE).

关键词： Thermoplastic polyethylene elastomers α-Diimine nickel pre-catalysts Ethylene polymerization Mechanical properties Highly branched polyethylene

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Investigating the Effects of Para-methoxy Substitution in Sterically Enhanced Unsymmetrical Bis(arylimino)pyridine-cobalt Ethylene Polymerization Catalysts

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Chinese Journal of Polymer Science 2022年第3期40卷 266-279,I0007页

作者： Yi Yan Shi-Fang Yuan Ming Liu Gregory A.Solan Yan-Ping Ma Tong-Ling Liang wen-hua sun Institute of Applied Chemistry Shanxi UniversityTaiyuan 030006China Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences Institute of Chemistry Chinese Academy of SciencesBeijing 100190China Department of Chemistry University of LeicesterUniversity RoadLeicester LE17RHUK State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

A group of five bis(arylimino)pyridine-cobalt(Ⅱ)chloride complexes,[2-{(2,6-(Ph_(2)CH)_(2)-4-MeOC_(6)H_(2))N=CMe}-6-(ArN=CMe)C_5 H_(3)N]CoCl_(2)(Ar=2,6-Me_(2)C_(6)H_(3)Co1,2,6-Et_(2)C_(6)H_(3)Co2,2,6-iPr_(2)C_(6)H_(3)Co3,2,4,6-Me_(3)C_(6)H_(2)Co4,2,6-Et_(2)-4-MeC_(6)H_(2)Co5),each containing one N-4-methoxy-2,6-dibenzhydrylphenyl group and one smaller sterically/electronically variable N-aryl group,have been synthesized in good yield(>71%)from the corresponding neutral terdentate nitrogen-donor precursor,*** complexes have been characterized by^(1)H-NMR and FTIR spectroscopy with the former highlighting the paramagnetic nature of these cobaltous species and the unsymmetrical nature of the chelating *** molecular structures of Co3 and Co4 emphasize the steric differences of the two inequivalent N-aryl groups and the distorted square pyramidal geometry about the metal *** the presence of MAO or MMAO,Co1-Co5 collectively displayed high activities for ethylene polymerization producing high molecular weight polyethylenes that,in general,exhibited narrow dispersities(M_w/M_n values:2.12-4.07).Notably,the least sterically hindered Co1 when activated with MAO was the most productive(6.92×10^(6)g_(PE)·mol^(-1)_((Co))·h^(-1))at an operating temperature of60℃.Conversely,the most sterically hindered Co3/MMAO produced the highest molecular weight polyethylene(M_w=6.29×10^(5)g·mol^(-1)).All the polymers displayed high linearity as demonstrated by their melting temperatures(>130℃)and their~1 H-and^(13)C-NMR *** comparison of Co1 with its para-methyl,-chloro and-nitro counterparts,the presence of the para-methoxy substituent showed the most noticeable effect of enhancing the thermal stability of the catalyst.

关键词： Cobalt(II)precatalyst Ethylene polymerization High molecular weight polyethylene Electronic effects Thermal stability

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Goal-Oriented Control Systems(GOCS):From HOW to WHAT

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 816-819页

作者： wen-hua Chen the Department of Aeronautical and Automotive Engineering Loughborough UniversityLeicestershireLE113TUU.K.

Brief:New control theory is required to underpin safe design and deployment of future highly automated systems to deal with uncertain environments and complicated tasks,enabled by AI and other advanced ***-Oriented Control Systems offer potential to transform the control system design from currently instructing a control system how to perform a task to specifying what is to be achieved.

关键词： automated instru system

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Ultra-high-rate Bi anode encapsulated in 3D lignin-derived carbon framework for sodium-ion hybrid capacitors

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Rare Metals 2024年第3期43卷 1037-1047页

作者： Ze-hua Lin Xue-Qing Qiu Xi-Hong Zu Xiao-Shan Zhang Lei Zhong Shi-Rong sun Shu-hua Hao Ying-Juan sun wen-Li Zhang School of Chemical Engineering and Light Industry Guangdong University of Technology(GDUT)Guangzhou510006China Jieyang Branch of Chemistry and Chemical Engineering Guangdong Laboratory(Rongjiang Laboratory) Jieyang515200China School of Advanced Manufacturing Institute of Green Chemistry and Advanced MaterialsGuangdong University of TechnologyJieyang515200China

Bismuth(Bi),as an alloy-based anode material,has attracted much atte ntion in the developme nt of sodiumion hybrid capacitors(SIHCs)due to its high theoretical ***,the volume expansion of the Bi-based anode during the sodiation/desodiation process results in limited rate *** the present work,a porous Bi-based composite was constructed by a one-step hydrothermal method,and Bi was encapsulated in ligninderived nitrogen-doped porous carbon(Bi@LNPC)after *** obtained Bi nanoparticles could effectively adapt to the strain and shorten the diffusion distance of Na^(+).In addition,porous carbon skeleton provides a rigid conductive network for electronic ***,the assembled sodium-ion half-cell with Bi@LNPC anode shows ultra-high-rate *** the current density was enhanced from 0.1 to 50 A·g^(-1),the specific capacity decreased slightly from 351.5 to 342.8 mAh·g^(-1).Even at an extremely high current density of 200 A·g^(-1),it retains 81.3%capacity retention when compared to a current density of 1 A·g^(-1).The SIHCs assembled by Bi@LNPC show a high energy density of 63 Wh·kg^(-1).This work provides an effective method for developing high-rate Bi anode materials for sodium-ion hybrid capacitors(SIHCs)and sodium-ion batteries(SIBs).

关键词： Bismuth Lignin Sodium-ion batteries Sodium-ion hybrid capacitors Rate Porous carbon

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Cardiovascular computed tomography in cardiovascular disease:An overview of its applications from diagnosis to prediction

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Journal of Geriatric Cardiology 2024年第5期21卷 550-576页

作者： Zhong-hua sun Discipline of Medical Radiation Science Curtin Medical SchoolCurtin UniversityPerthAustralia Curtin Health Innovation Research Institute(CHIRI) Curtin UniversityPerth 6012Australia

Cardiovascular computed tomography angiography(CTA)is a widely used imaging modality in the diagnosis of cardiovascular *** in CT imaging technology have further advanced its applications from high diagnostic value to minimising radiation exposure to *** addition to the standard application of assessing vascular lumen changes,CTA-derived applications including 3D printed personalised models,3D visualisations such as virtual endoscopy,virtual reality,augmented reality and mixed reality,as well as CT-derived hemodynamic flow analysis and fractional flow reserve(FFRCT)greatly enhance the diagnostic performance of CTA in cardiovascular *** widespread application of artificial intelligence in medicine also significantly contributes to the clinical value of CTA in cardiovascular *** value of CTA has extended from the initial diagnosis to identification of vulnerable lesions,and prediction of disease extent,hence improving patient care and *** this review article,as an active researcher in cardiovascular imaging for more than 20 years,I will provide an overview of cardiovascular CTA in cardiovascular *** is expected that this review will provide readers with an update of CTA applications,from the initial lumen assessment to recent developments utilising latest novel imaging and visualisation *** will serve as a useful resource for researchers and clinicians to judiciously use the cardiovascular CT in clinical practice.

关键词： diagnosis cardiovascular prediction

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Recent Progress on Transition Metal （Fe, Co, Ni, Ti and V） Complex Catalysts in Olefin Polymerization with High Thermal Stability

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Chinese Journal of Chemistry 2017年第5期35卷 531-540页

作者： Zhifeng Ma wenhong Yang wen-hua sun Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

The design and synthesis of transition metal complexes with high thermal stability in olefin polymerization have become more and more important in order to meet the need of industrial *** review focuses on the transition metal complex catalyst with high thermal stability containing different structures,including the backbone of bis（imino）pyridine,a-diimine and other types of *** the catalytic activity,the influence of reaction temperature on the molecular weight and molecular weight distribution of the obtained polymer was also *** plausible mechanism on the stability of catalysts at high temperature was proposed,which may give guidance to design catalyst with good thermal stability.

关键词： thermal stability transition metal complex olefin polymerization homogenous catalysis ligand effects

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Misdiagnosis of synovial sarcoma-cellular myofibroma with SRFRELA gene fusion:A case report

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World Journal of Clinical Cases 2024年第7期12卷 1326-1332页

作者： Ying Zhou Yi-wen sun Xiao-Yang Liu Dan-hua Shen Department of Pathology Peking University People’s HospitalBeijing 100044China

BACKGROUND Cellular myofibroma is a rare subtype of myofibroma that was first described in *** diagnosis is often challenging because of its relative rarity,lack of known genetic abnormalities,and expression of muscle markers that can be confused with sarcomas that have myogenic ***,scholars have limited knowledge of this disease,and published cases are *** accumulation of diagnostic and treatment experiences is *** SUMMARY A 16-year-old girl experienced left upper limb swelling for 3 *** sought medical attention at a local hospital 10 months ago,where magnetic resonance imaging revealed a 5-cm soft tissue *** biopsy performed at a local hospital resulted in the diagnosis of a spindle cell soft tissue *** patient was referred to our hospital for limb salvage surgery with endoprosthetic *** was initially diagnosed with a synovial ***,clinical management with chemotherapy was continued for the malignant *** pathology department also performed fluorescence in situ hybridization for result validation,which returned negative for SS18 gene breaks,indicating that it was not a synovial ***-generation sequencing was used to identify the SRF-RELA *** final pathological diagnosis was a cellular/myofibroblastic neoplasm with an SRF-RELA gene *** patient had initially received two courses of chemotherapy;however,chemotherapy was discontinued after the final *** This case was misdiagnosed because of its rare occurrence,benign biological behavior,and pathological similarity to soft tissue sarcoma.

关键词： Cellular myofibroma SRF RELA Fusion Pathology Case report

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Weakly Approximate Diagonalization of Homomorphisms into Finite von Neumann Algebras

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2187-2194页

作者： wen hua QIAN Jun Hao SHEN wen Ming WU School of Mathematical Sciences Chongqing Normal UniversityChongqing 401331P.R.China Department of Mathematics and Statistics University of New HampshireDurhamNH 03824USA

Let A be a unital C^(∗)-algebra and B a unital C^(∗)-algebra with a faithful traceτ.Let n be a positive *** give the definition of weakly approximate diagonalization(with respect toτ)of a unital homomorphismφ:A→Mn(B).We give an equivalent characterization of McDuff II1 *** show that,if A is a unital nuclear C^(∗)-algebra and B is a type II1 factor with faithful traceτ,then every unital^(∗)-homomorphismφ:A→Mn(B)is weakly approximately *** B is a unital simple infinite dimensional separable nuclear C^(∗)-algebra,then any finitely many elements in Mn(B)can be simultaneously weakly approximately diagonalized while the elements in the diagonals can be required to be the same.

关键词： Weakly approximately diagonalizable McDuff factors nuclear hyperfinite

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New family of single-component Ni catalysts for ethylene polymerization to high and ultrahigh molecular weight polyethylene

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Science China Chemistry 2020年第6期63卷 753-754页

作者： Artem A.Antonov wen-hua sun Konstantin P.Bryliakov Boreskov Institute of Catalysis Pr.Lavrentieva 5Novosibirsk 630090Russia Novosibirsk State University Pirogova 1Novosibirsk 630090Russia Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences Institute of ChemistryChinese Academy of SciencesBeijing 100190China CAS Research/Education Center for Excellence in Molecular Sciences University of Chinese Academy of SciencesBeijing 100049China

Since the milestone discovery of Ni(II)salicylaldiminate catalysts by Grubbs and co-workers[1],nickel(II)complexes with N,N-and N,O-donor ligands have strengthened their lead in the search for highly active platforms for olefins homo-and copolymerization with various co-monomers,including those with polar groups,to achieve polymers with precisely controlled microstructures[2,3].

关键词： discovery catalysts co-monomers

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