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Chinese Journal of Polymer Science 2024年第8期42卷 1085-1092页

作者： hong-Yu Ji hong-liang mu Chun-Feng Tang Yu-Xing Zhang Yue Chi Zhong-Bao Jian Key Laboratory of Advanced Structural Materials Ministry of EducationSchool of Materials Science and EngineeringChangchun University of TechnologyChangchun 130012China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Olefin polymerization is one of the most im portant chemical reactions in *** work presents a strategy that emphasizes the synergistic meta/poro-steric hindrance of N-aryl groups and electronic effects in newly synthesized neutral salicylaldiminato nickel *** nickel(Ⅱ)catalysts exhibit exceptional thermostability,ranging from 30℃to 130℃,demonstrating enhanced catalytic activities and broadly regulated polyethylene molecular weights(3-341 kg·mol^(-1))and controlled polymer branch density(2-102 brs/1000C).The preferred catalyst Ni3 with concerted steric and electronic effects enables the production of solid-state semi-crystalline polyethylene materials at temperatures below 90℃.Notably,Ni3 exhibits an impressive tolerance of 110℃and can withstand even the challenging polymerization temperature of 130℃,leading to the production of polyethylene wax and ***,functionalized polyethylene is produced.

关键词： Polyolefin Salicylaldiminato ligand Nickel catalyst Oil Wax

Ethylene Polymerization and Copolymerization with Polar Monomers by Benzothiophene-bridged BPMO-Pd Catalysts

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Chinese Journal of Polymer Science 2020年第6期38卷 579-586页

作者： hong-liang mu Jun-Hao Ye Guang-Lin Zhou Kang-Kang Li Zhong-Bao Jian State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

A series of new bisphosphine-monoxide(BPMO)ligands based on benzothiophene backbone and the corresponding palladium complexes{k2-P(O)(Ph)2-3-PR1R2-C8H4S}PdMeCl{2a:R1=R2=Ph;2b:R1=R2=2-0Me-Ph;2c:R1=R2=2-CF3-Ph;2d:Rl=Ph,R2=2-(2',6'-(OMe)2C6Hz)-C6H4}were synthesized and fully characterized by1H-,13C-,31P-,and 2D-NMR spectroscopy and single-crystal X-ray *** the presence of Na+B[3,5-(CF3)2C6H3]4(NaBArF),these complexes showed very high activities(up to 2.0 x 10’g-mol-1.h-)for ethylene *** significantly,these catalysts enabled the copolymerization of ethylene with a broad scope of commercially available polar comonomers such as acrylates,acrylic acid,acrylonitrile,vinyltrialkoxysilane,allyl acetate,and long-chain 6-chloro-1-hexene to give functionalized polyethylene with reasonable catalytic activities(up to 105 g-mol-l.h-)and incorporations(up to 5.3 mol96).This contribution suggests that,besides the modulation of conventionally steric and electronic factors,the connectivity(at dfferent linking positions)of BPMO(P,O)donors to the heteroaryl backbone also greatly infuences the catalyst properties in terms of catalytic activity,polymer branching content,comonomer scope,and comonomer incorporation.

关键词： Olefin polymerization Bisphosphine monoxide Plladium Polar monomers Heteroaryl backbone

Enhancement on Hemilabile Phosphine-Amide Palladium and Nickel Catalysts for Ethylene(Co)Polymerization with Polar Monomers Using a Cyclizing Strategy

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Chinese Journal of Polymer Science 2022年第3期40卷 241-247,I0005页

作者： Lei Cui Yu-Kai Chu Da-Jun Liu Ying-Feng Han hong-liang mu Zhong-Bao Jian State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Chemistry and Environmental Engineering Changchun University of Science and TechnologyChangchun 130022China Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry and Materials ScienceNorthwest UniversityXi’an 710127China

To address the issue of hemilabile catalyst in olefin polymerization catalysis, a cyclizing strategy was used to construct novel N-bridged phosphine-carbonyl palladium and nickel catalysts, resulting in improvements on ethylene(co)polymerizations. The N-bridged phosphinecarbonyl Pd catalysts(Pd1-Pd5) and Ni catalysts(Ni1-Ni5) bearing five-to eight-membered-ring structures were designed and *** performance for ethylene(co)polymerization became better as the size of N-containing bridge increased. The seven-membered-ring bridged catalysts Pd4 and Ni4 exhibited the best performance in terms of catalytic activity, polymer molecular weight and incorporation of acrylates and acrylic acid. The better performance of these catalysts bearing larger-size bridges was tentatively attributed to the methyleneinduced higher electron density around nitrogen, which strenghtens the coordination of carbonyl group to metal center, and also to the steric effect offered by this cyclization. This work provides a new strategy to enhance hemilabile polymerization catalysts.

关键词： Polyolefins Cyclizing strategy Phosphine ligands Polar monomers Late transition metal catalysts

Efficient Addition Polymerization of Norbornene with Polar Norbornene Derivatives by Neutral Nickel(Ⅱ) Catalysts

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Chinese Journal of Polymer Science 2019年第12期37卷 1215-1223,I0005页

作者： Ling Guo Yan-Ping Zhang hong-liang mu Li Pan Kai-Ti Wang Huan Gao Bin Wang Zhe Ma Yue-Sheng Li Tianjin Key Lab of Composite&Functional Materials School of Material Science and EngineeringTianjin UniversityTianjin UniversityTianjin 300350China Changchun Institute of Applied Chemistry Chinese Academy of SciencesChangchun 130022China School of Materials Science and Engineering Chongqing University of TechnologyChongqing 400054China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China

A series of nickel complexes{4 a:[(2,6-iPr2C6H3)N=CHC16H12O]Ni(Me)(Py),4b:[(2,6-iPr2C6H2OCH3)N=CHC16H12O]-Ni(Me)(Py),4 c:[(2,6-iPr2C6H2Cl)N=CHC16H12O]Ni(Me)(Py),and 4d:[(2,6-iPr2C6H2CF3)N=CHC16H12O]Ni(Me)(Py)}based onβ-ketiminato ligands bearing various electron-donating or electron-withdrawing substituents on the para-position of the aniline group were synthesized and unambiguously *** X-ray crystallographic analysis showed that complexes 4 b and 4 d adopted a nearsquare-planar geometry,and the anilines bearing a para-OMe or―CF3 group were found to situate on the axial position of the metal *** complexes exhibited high activities up to 1.25×10^7–1.35×10^7 g PNB·molNi^–1·h^–1 toward norbornene(NBE)addition polymerization(conversion>91.2%in 2 min)under low loading of B(C6F5)3(B/Ni=3)at 30°C,affording polymers with high molecular weight up to 2.54×10^6–3.18×10^*** levels of decrease in catalytic activities could be observed for all catalysts as the reaction temperature increased;4 d bearing a strong electron-withdrawing―CF3 group showed the highest activity at 70°C,while others exhibited notable decrease in catalytic activity with the raise in reaction *** 4 a–4 d showed remarkable tolerance to polar groups and could efficiently promote the copolymerization of NBE with its polar derivatives,including NBE bearing small acetate and hydroxyl group,as well as bulky oligomers,yielding copolymers with high functional NBE *** NBE copolymers with high functional comonomer incorporations and improved solubility were obtained in high yields.

关键词： Neutral nickel catalysts Norbornene Norbornene derivatives Vinyl-type polymerization

High-Order Two-Scale Asymptotic Paradigm for the Elastodynamic Homogenization of Periodic Composites

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Acta Mechanica Solida Sinica 2024年第1期37卷 124-138页

作者： Wei-Zhi Luo mu He liang Xia Qi-Chang He State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China Laboratoire Modélisation et Simulation multi-Echelle MSME UMR 8208 CNRSUniversite Gustave Eiffel77454 Marne-la-ValléeFrance

The classical two-scale asymptotic paradigm provides macroscopic and microscopic analyses for the elastodynamic homogenization of periodic composites based on the spatial or/and temporal variable,which offers an approximate framework for the asymptotic homogenization analysis of the motion ***,in this framework,the growing complexity of the homogenization formulation gradually becomes an obstacle as the asymptotic order *** such a context,a compact,fast,and accurate asymptotic paradigm is *** work reviews the high-order spatial two-scale asymptotic paradigm with the effective displacement field representation and optimizes the implementation by symmetrizing the tensor to be ***,the modified implementation gets rid of the excessive memory consumption required for computing the high-order tensor,which is demonstrated by representative one-and two-dimensional *** numerical results show that(1)the contrast of the material parameters between media in composites directly affects the convergence rate of the asymptotic results for the homogenization of periodic composites,(2)the convergence error of the asymptotic results mainly comes from the truncation error of the modified asymptotic homogenized motion equation,and(3)the excessive norm of the normalized wavenumber vector in the two-dimensional inclusion case may lead to a non-convergence of the asymptotic results.

关键词： Composites Homogenization Asymptotic analysis Dynamics Dispersion

BACNN: multi-scale feature fusion-based bilinear attention convolutional neural network for wood NIR classification

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Journal of Forestry Research 2024年第4期35卷 202-214页

作者： Zihao Wan hong Yang Jipan Xu hongbo mu Dawei Qi College of Science Northeast Forestry UniversityHarbin 150040People’s Republic of China

Effective development and utilization of wood resources is *** modification research has become an integral dimension of wood science research,however,the similarities between modified wood and original wood render it challenging for accurate identification and classification using conventional image classification ***,the development of efficient and accurate wood classification techniques is *** paper presents a one-dimensional,convolutional neural network(i.e.,BACNN)that combines near-infrared spectroscopy and deep learning techniques to classify poplar,tung,and balsa woods,and PVA,nano-silica-sol and PVA-nano silica sol modified woods of *** results show that BACNN achieves an accuracy of 99.3%on the test set,higher than the 52.9%of the BP neural network and 98.7%of Support Vector Machine compared with traditional machine learning methods and deep learning based methods;it is also higher than the 97.6%of LeNet,98.7%of AlexNet and 99.1%of ***,the classification method proposed offers potential applications in wood classification,especially with homogeneous modified wood,and it also provides a basis for subsequent wood properties studies.

关键词： Wood classification Near infrared spectroscopy Bilinear network SE module Anti-noise algorithm

The journey towards physiology and pathology: Tracing the path of neuregulin 4

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Genes & Diseases 2024年第2期11卷 687-700页

作者： Min Chen Jieying Zhu hongyang Luo Wangjing mu liang Guo School of Exercise and Health and Shanghai Frontiers Science Research Base of Exercise and Metabolic Health Shanghai University of SportShanghai 200438China

Neuregulin 4 (Nrg4),an epidermal growth factor (EGF) family member,can bind to and activate the ErbB4 receptor tyrosine ***4 has five different isoforms by alternative splicing and performs a wide variety of ***4 is involved in a spectrum of physiological processes including neurobiogenesis,lipid metabolism,glucose metabolism,thermogenesis,and *** pathological processes,Nrg4 inhibits inflammatory factor levels and suppresses apoptosis in inflammatory *** addition,Nrg4 could ameliorate obesity,insulin resistance,and cardiovascular ***,Nrg4 improves non-alcoholic fatty liver disease (NAFLD) by promoting autophagy,improving lipid metabolism,and inhibiting cell death of ***,Nrg4 is closely related to the development of cancer,hyperthyroidism,and some other ***,elucidation of the functional role and mechanisms of Nrg4 will provide a clearer view of the therapeutic potential and possible risks of Nrg4.

关键词： Angiogenesis Cardiovascular diseases Inflammation Insulin resistance Lipid and glucose metabolism NAFLD Neurobiogenesis Obesity

Atomic force microscopy-based nanoscale infrared techniques for liquid environments

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Science Bulletin 2024年第2期69卷 151-153页

作者： Jian Li Jing liang mu-Hao Lan Xing-Hua Xia State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Infrared(IR)light energy matches well with the vibration and rotation of chemical bonds in molecules,hence IR spectroscopy is commonly used for accurate molecular identification[1].Conventional IR analysis involves bulk samples,providing averaged information of the entire *** spatially-resolved investigation of heterogeneous sample properties is constrained by the micrometer-level spatial resolution of optical IR microscopy.

关键词： spatially hence rotation

Cracking on a nickel-based superalloy fabricated by direct energy deposition

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China Foundry 2024年第4期21卷 311-318页

作者： Xue Zhang Ya-hang mu liang Ma Jing-jing liang Yi-zhou Zhou Xiao-feng Sun Jin-guo Li School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China

Cracks have consistently been a significant challenge limiting the development of additive manufactured nickel-based *** is essential to investigate the location of cracks and their forming *** study extensively examines the impact of solidification process,microstructural evolution,and stress concentration on crack initiation during direct energy deposition(DED).The results emphasize that the crack formation is significantly related to large-angle grain boundaries,rapid cooling *** caused by large-angle grain boundaries and a fast-cooling rate predominantly appear near the edge of the deposited *** cracks are more likely to form near the top of the deposited sample,due to the presence ofγ/γ'*** secondary dendritic arm and the carbides in the interdendritic regions can obstruct liquid flow during the final stage of solidification,which results in the formation of solidification cracks and *** work paves the way to avoid cracks in nickel-based superalloys fabricated by DED,thereby enhancing the performance of superalloys.

关键词： location cracks direct energy deposition nickel-based superalloys

An exo Probe-based Reverse Transcription and Recombinase Polymerase Amplification for Rapid Detection of Feline Calicivirus in Cats

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Biomedical and Environmental Sciences 2024年第3期37卷 325-330页

作者： mu hong Yun ZHOU hong Lei JING Zheng LU Wei ZHANG Jian Wei Jiangsu Agri-animal Husbandry Vocational College Taizhou 225300JiangsuChina Boehringer Ingelheim Animal Health(Shanghai)Co. LTD.Shanghai 200040China

Feline calicivirus(FCV)was a highly prevalent RNA virus causing upper respiratory tract infections in cats through the mouth and nose around the world,result in the death of cats especially under 1 year old with upper respiratory tract disease(URTD)and virulent systemic disease(FCV-VSD)[1].Infected cats usually presented with mouth ulcers,salivation and ***,both recovered cats and asymptomatic carriers can still carry and spread the FCV virus for extended periods of time,contributing to the potential for *** presented a significant threat to the health and lives of cats,and rare wildlife and took a heavy financial loss on the pet industry,making the prevention and control of the virus ***,rapid identification of FCV in clinical samples was necessary to prevent the spread of FCV and avoid financial loss.

关键词： prevention respiratory Probe