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Synthesis,Characterization of Polyethylene Ionomers and Their Antibacterial Properties

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Chinese Journal of Polymer Science 2024年第8期42卷 1077-1084页

作者： Jia-Jia Wu Fei Wang Peng-Qi Wan Li Pan Chun-sheng Xiao Zhe Ma Yue-sheng Li Tianjin Key Lab Composite&Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin 300350China Key Lab Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Owing to its high production volume and wide range of application s,polyethylene has gained a great deal of attention,but its low surface energy and non-polar nature have limited its application in some important *** this study,ethylene/11-iodo-1-undecene copolymers were prepared and used as the intermediates to afford a series of imidazolium-based ionomers bearing methanesulfonate(CH_(3)SO_(3)^(-)),trifluoromethanesulfonate(CF_(3)SO_(3)^(-)),or bis(trifluoromethane)sulfonimide(Tf_(2)N^(-))*** tensile test results showed that the stress-at-break(7.8-25.6 MPa)and the elongation-at-break(445%-847%)of the ionomers could be adjusted by changing the counterion species and the ionic group *** importantly,the ionomers exhibited marvelous antibacterial activities against Staphylococcus aureus(***)and Escherichia coli(***).The ionomers bearing Tf_(2)N^(-)exhibited antibacterial activities>99%against both *** and *** when ionic content reached 9.1%.The imidazolium-based ionomers prepared in this work demonstrated excellent comprehensive properties,especially highefficient and broad-spectrum antibacterial ability,exhibiting the potential fo r the application as the antibacterial materials in packaging,medical,and other fields.

关键词： Polyethylene Ionomer Polymerization catalysis Imidazolium Antibacterial material

Narrowband blue emitter based on fused nitrogen/carbonyl combination with external quantum efficiency approaching 30%

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Science China Chemistry 2024年第1期67卷 351-359页

作者： Long Chen Jia-Heng Cai You-Jun Yu Yang-Kun Qu sheng-Yi Yang sheng-Nan Zou Rui-Hong Liu Dong-Ying Zhou Liang-sheng Liao Zuo-Quan Jiang Institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials&DevicesSoochow UniversitySuzhou 215123China Macao Institute of Materials Science and Engineering Macao University of Science and TechnologyMacao 999078China

Multi-resonance thermally activated delayed fluorescence(MR-TADF)emitters can enable narrowband emission with high color purity and electroluminescence ***/carbonyl(N/C=O)system is receiving increasing attention while the nitrogen/boron(N/B)system has been widely *** decoration is an effective approach for N/B type MR-TADF system but always leads to broadening and red-shifting of the emission band in N/C=O MR-TADF *** attribute these unfavorable phenomena to the formation of intramolecular charge transfer between the MR-core and peripheral *** address this issue,we have developed a new strategy by decorating DMQAO(a fused N/C=O MR-core)with a triazine acceptor and a neutral terphenyl group to construct MTDMQAO and MBDMQAO,*** introduction of the triazine acceptor not only realizes efficient narrowband emission in MTDMQAO,but also accelerates the reverse intersystem crossing process through enhanced spin-orbital *** a result,MTDMQAO exhibits a significantly higher external quantum efficiency of 29.4%compared to the referent emitters,validating the rationality of our derivation *** study highlights the potential of the N/C=O system for MR-TADF emitters and provides important insights for understanding the difference between N/B and N/C=O systems.

关键词： carbonyl group narrowband acceptor decoration thermally activated delayed fluorescence OLEDs

Effect of short-time low-temperature austenitizing on microstructure and mechanical properties of DT300 ultra-high strength steel fabricated by laser powder bed fusion

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Journal of Iron and Steel Research International 2024年第7期31卷 1763-1777页

作者： Chen-yang Jiang Xiao-qiang Li Jin-tao Wang Hao Luo sheng-qing Gao sheng-guan Qu Chao Yang National Engineering Research Centre of Near-Net-Shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510640GuangdongChina Institute of New Materials Guangdong Academy of ScienceGuangzhou 510650GuangdongChina

To address the inhomogeneous microstructure and improve the mechanical properties of DT300 ultra-high strength steel specimens fabricated by laser powder bed fusion,different post-heat treatment schedules are *** the increase in austenitizing temperature and time,the migration rate of austenite grain boundaries continuously increases with the dissolution of nano-carbides,and the formation of nano-oxides and twin martensite is also inhibited *** rapid growth in the size of prior austenite grains and martensite laths,as well as the decrease in the content of nano-oxides and twin martensite,led to a rapid decrease in the strength(yield strength and ultimate tensile strength)from HT2 to HTF *** HT1 specimens(austenitizing at 830℃for 30 min,then oil quenching and tempering at 300℃for 120 min and finally air cooling)display excellent mechanical properties of yield strength of 1572 MPa,ultimate tensile strength of 1847 MPa,elongation of 9.84%,and fracture toughness of 106 MPa m^(1/2),which are counterparts to those of conventional DT300 steel forgings after heat treatment.

关键词： DT300 ultra-high strength steel Laser powder bed fusion-Short-time low-temperature austenitizing Microstructure Mechanical property

Recent breakthrough in AI-driven materials science:tech giants introduce groundbreaking models

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Materials Futures 2024年第2期3卷 170-174页

作者： Miao Liu sheng Meng Institute of Physics Chinese Academy of SciencesBeijing 100190People’s Republic of China Songshan Lake Materials Laboratory DongguanGuangdong 523808People’s Republic of China

A close look at Google’s GNoME inorganic materials dataset(Merchant et al 2023 Nature 62480–85),and 11 things you would like to know.

关键词： AI GNoME dataset AI+materials science

Research,application and development of inorganic binder for casting process

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China Foundry 2024年第5期21卷 461-475页

作者： Xiao-long Gong sheng-li Hu Zi-tian Fan State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

Inorganic binder used in casting process has the advantages of low odor,labor-friendly conditions,and relatively low cost,which is one of the main development directions for casting molding materials in the ***,compared to organic binders(such as resin binders),inorganic binders exhibit lower bonding strength and are more sensitive to environmental *** sensitivity poses challenges,particularly in the reclamation of used sand,thus limiting their broader *** this paper,the research and application status of inorganic binders(mainly silicate inorganic binders)and their curing methods are *** addition,the research and application of phosphate inorganic binders and 3D printing inorganic binders that are being developed are ***,a detailed comparative analysis is conducted on the challenging issue of“reclamation for used sand”in the application of inorganic ***,the development direction of inorganic binders is clarified.

关键词： inorganic binder silicate system phosphate system 3D printing used sand reclamation development trend

Flexible nanoimprint lithography enables high-throughput manufacturing of bioinspired microstructures on warped substrates for efficient III-nitride optoelectronic devices

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Science Bulletin 2024年第13期69卷 2080-2088页

作者： Siyuan Cui Ke Sun Zhefu Liao Qianxi Zhou Leonard Jin Conglong Jin Jiahui Hu Kuo-sheng Wen sheng Liu shengjun Zhou Center for Photonics and Semiconductors School of Power and Mechanical EngineeringWuhan UniversityWuhan 430072China The Institute of Technological Sciences Wuhan UniversityWuhan 430072China Department of Mechanical and Mechatronics Engineering University of WaterlooWaterloo ONN2L 3G1Canada Jiangxi SMTC Semiconductor Co. Ltd.Nanchang 330096China

III-nitride materials are of great importance in the development of modern optoelectronics,but they have been limited over years by low light utilization rate and high dislocation densities in heteroepitaxial films grown on foreign substrate with limited refractive index contrast and large lattice ***,we demonstrate a paradigm of high-throughput manufacturing bioinspired microstructures on warped substrates by flexible nanoimprint lithography for promoting the light extraction *** design a flexible nanoimprinting mold of copolymer and a two-step etching process that enable high-efficiency fabrication of nanoimprinted compound-eye-like Al2O3 microstructure(NCAM)and nanoimprinted compound-eye-like SiO_(2)microstructure(NCSM)template,achieving a 6.4-fold increase in throughput and 25%savings in economic costs over stepper projection *** to NCAM template,we find that the NCSM template can not only improve the light extraction capability,but also modulate the morphology of AlN nucleation layer and reduce the formation of misoriented GaN grains on the inclined sidewall of microstructures,which suppresses the dislocations generated during coalescence,resulting in 40%reduction in dislocation *** study provides a low-cost,high-quality,and high-throughput solution for manufacturing microstructures on warped surfaces of III-nitride optoelectronic devices.

关键词： Flexible nanoimprint lithography Bioinspired Micro-and nano-manufacturing III-nitride epitaxy Optoelectronic devices

Hydrodynamic characteristics and particle tracking of 90° lateral intakes at an inclined river slope

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Water Science and Engineering 2024年第2期17卷 197-208页

作者： Wei He Si-yuan Feng Jian Zhang Hong-wu Tang Yang Xiao sheng Chen Chun-sheng Liu College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China State Key Laboratory of Hydrology Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China Collaborative Innovation Center on Water Safety and Water Science Hohai UniversityNanjing 210098China

Lateral intakes are common in *** pump effciency and sediment deposition are determined by the local hydrodynamic characteristics and mainstream division *** hydraulic characteristics of lateral withdrawal from inclined river slopes at different intake elevations should be ***,the division width exhibits significant vertical non-uniformity at an inclined river slope,which should be ***,a three-dimensional(3-D)hydrodynamic and particle-tracking model was developed with the Open Source Field Operation and Manipulation(Open FOAM),and the model was validated with physical model tests for 90°lateral withdrawal from an inclined side *** flow fields,withdrawal sources,and division widths were investigated with different intake bottom elevations,withdrawal discharges,and main channel *** study showed that under inclined side bank conditions,water entered the intake at an oblique angle,causing significant 3-D spiral flows in the intake rather than two-dimensional closed recirculation.A lower withdrawal discharge,a lower bottom elevation of the intake,or a higher main channel velocity could further strengthen this *** average division width and turbulent kinetic energy were smaller under inclined side bank conditions than under vertical bank *** a low intake bottom elevation,a low withdrawal discharge,or a high main channel velocity,the sources of lateral withdrawal were in similar ranges near the local inclined bank in the vertical *** inclined slope conditions,sediment deposition near the intake entrance could be reduced,compared to that under vertical slope *** results provide hydrodynamic and sediment references for engineering designs for natural rivers with inclined terrains.

关键词： Lateral withdrawal Hydrodynamic characteristics Particle tracking Inclined river slope Bottom elevation of intake OpenFOAM

Sex-biased adaptation shapes uniparental gene pools in Tibetans

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Science China(Life Sciences) 2024年第3期67卷 611-613页

作者： Min-sheng Peng Ya-Ping Zhang State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of SciencesKunming 650201China KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases Kunming Institute of ZoologyChinese Academy of SciencesKunming 650201China Kunming College of Life Science University of Chinese Academy of SciencesKunming 650204China State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan School of Life SciencesYunnan UniversityKunming 650091China

During the past two decades, a series of archaeological and genetic investigations substantially improve our perception of the hominin settlement of the Tibetan Plateau(Zhang et al., 2022). In addition to the identifi... 详细信息

关键词： Tibetan Plateau altitude

Landsat Image-Based Spatiotemporal Variation Analysis of Erosion and Deposition off the Qingshuigou of the Yellow River Delta from 1984 to 2021

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Journal of Ocean University of China 2024年第5期23卷 1173-1184页

作者： DONG sheng LI Songda TAO Shanshan College of Engineering Ocean University of ChinaQingdao 266404China

Owing to climate change and human activity,the Qingshuigou of the Yellow River Delta(YRD)has undergone dynamic changes in erosion and ***,studying these changes is important to ensure ecological protection and sustainable *** this study,the trend of erosion-deposition evolution in the Qingshuigou was investigated based on 38 coastline phases extracted from Landsat series images of the YRD at one-year intervals from 1984 to *** periodicity of the scouring and deposition evolution was also analyzed using wavelet *** showed that the total area of the Qingshuigou was affected by deposition and erosion and that the fluctuation first increased and then *** total area reached a maximum in *** depositional area first increased and then decreased,whereas the overall erosion area *** and erosion areas showed periodic changes to some extent;however,the periodic signal intensity ***,factors including channel morphological evolution and variations in water and sediment discharge affect the spatiotemporal dynamics of erosion and deposition *** application of nonconsistency tests finally revealed that deposition area and flushing magnitude exhibited non-stationarities,which are potentially attributed to impacts from climatic change drivers.

关键词： Yellow River Delta coastline erosion and deposition remote sensing wavelet analysis