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Rare Metals 2024年第2期43卷 533-542页

作者： Wei Li Jia-Jun Li Zhi-Fei Liu hong-yu ma Peng-Fei Fang Rui Xiong Jian-hong Wei Key Laboratory of Artificial Micro-and Nano-Structures of Ministry of Education School of Physics and TechnologyWuhan UniversityWuhan430072China

Constructing a S-scheme heterojunction with tight interface contact and fast charge transfer is beneficial to improving the photocatalytic hydrogen evolution ***,a unique one-dimensional(1D)/two-dimensional(2D)S-scheme heterojunction containing 1D Sb_(2)S_(3) nanorods and 2D ZnIn_(2)S_(4) with affluent sulfur vacancies(denoted as Sv-ZnIn_(2)S_(4)@Sb_(2)S_(3)) was *** introduced sulfur vacancy can promote the effective adsorption of H+for the following interfacial hydrogen-evolution ***,the larger contact area and stronger electron interaction between Sb_(2)S_(3) and ZnIn_(2)S_(4) effectively inhibits the recombination of photo-generated electron–hole pairs and abridges the migration distance of *** a result,the optimal Sv-ZnIn_(2)S_(4)@Sb_(2)S_(3) sample achieves H_(2) evolution activity of 2741.3 mol·h^(−1)·g^(−1),which is 8.6 times that of pristine ZnIn_(2)S_(4) and 3.0 times that of the Sv-ZnIn_(2)S_(4) *** on the experimental result,the photo-reactivity S-scheme mechanism of hydrogen evolution from water splitting with Sv-ZnIn_(2)S_(4)@Sb_(2)S_(3) is *** work provides an effective method for developing S-scheme heterojunction composites of transition metal sulfide with high hydrogen evolution performance.

关键词： ZnIn_(2)S_(4) nanosheets S-scheme heterojunction Sulfur vacancy Charge transfer and separation Photocatalytic H_(2)evolution

Synthetic Features and Mechanism for the Preparation of Vinyl Chloride-co-Butyl Acrylate-co-Vinyl Acetate Terpolymer via Precipitation Polymerization

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Chinese Journal of Polymer Science 2023年第11期41卷 1714-1724,I0006页

作者： Chang-Tong Song Xian-hong Zhang Dong Chen yu-hong ma Wan-Tai Yang State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China College of material Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China

Without any type of su rfactant or dispersing agent,precipitation polymerization has great superiorities in both polymer synthesis and *** the present work,the polymerization of vinyl chloride(VC),n-butyl acrylate(BA),and vinyl acetate(VAc)are conducted in the precipitation polymerization system and series of their random terpolymers poly(vinyl chloride-co-n-butyl acrylate-co-vinyl acetate)(PCBV)are synthesized *** effects of various polymerization conditions,including solvent polarity,temperature,initiator concentration,and monomer feed ratios on the polymerization kinetics,number-average molecular weight(M_(n)),and terpolymer composition are investigated *** solvent and the monomer feed ratio are crucial factors not only for the polymer morphology,but also for the reaction *** the non-polar solvent such as n-hexane,the PCBV displays particle morphology when the composition of BA ratio lower than 10 wt%.Otherwise,the PCBV forms a uniform polymer phase and precipitates out from the *** the polar solvent,e.g.,dimethyl carbonate(DMC)and ethanol,the PCBV polymer maintains a slurry state either in low or in high monomer feed ***,VC based ternary copolymer that obtained in n-hexane has much lower M_(n)(mass fraction(>40 wt%)compared with emulsion and suspension ***,the terpolymer can be easily sepa rated by simple centrifugation.

关键词： Precipitation polymerization Copolymerization Vinyl chloride Low molecular weight

Conventional Radical and RAFT Alternating Copolymerizations of Hydroxyalkyl Vinyl Ethers and Dialkyl maleates

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Chinese Journal of Polymer Science 2023年第12期41卷 1856-1867,I0006页

作者： Yan-Xin Zhang Dong Chen Gao-Fei Hu yu-hong ma Wan-Tai Yang Beijing Engineering Research Center of Syntheses and Applications of Waterborne Polymers College of materials Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China Analytical and Testing Center Beijing University of Chemical TechnologyBeijing 100029China

The alternating copolymerization of hydroxyalkyl vinyl ethers and dialkyl maleates is investigated by conventional radical polymerization and reversible addition-fragmentation chain transfer polymerization(RAFT).The influence of comonomer structure,comonomer feeding ratios,and monomer concentrations on the copolymerization and the copolymer structure have been investigated *** 2-hydroxyethyl vinyl ether(HEVE)and dimethyl maleates(DMM)as comonomers,a well-defined alternating copolymer is prepared with M_(n)=3400 and M_(w)/M_(n)=1.93 up to 71.6% *** alternating sequential chain structure of the copolymers has been proved by both NMR and matrixassisted laser desorption/ionization time-of-flight mass spectrometry(maLDI-TOF MS).The experimental reactivity ratios and theoretical calculated highest occupied molecular orbital and the lowest unoccupied molecular orbital of vinyl ethers and alkyl maleates support that these monomer pairs have tendency to form alternating *** 2-cyanopropan-2-yl N-methyl-N-(pyridin-4-yl)carbamodithioate as the RAFT agent,the molecular weight of HEVE and DMM copolymer increases with the monomer conversion,demonstrating a controlled radical polymerization feature with well-controlled molecular weight and relatively narrower molecular weight *** alternating copolymer of HEVE and DMM as macro-CTA(M_(n)=5200 and M_(w)/M_(n)=1.46),both the chain extension with HEVE and DMM(M_(n)=10400 and M_(w)/M_(n)=1.72)and block copolymerization with vinyl acetate have been successfully achieved(M_(n)=8500 and M_(w)/M_(n)=1.52).

关键词： Radical polymerization Vinyl ethers maleates Alternating copolymer RAFT polymerization

A framework from point clouds to workpieces

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Visual Computing for Industry,Biomedicine,and Art 2022年第1期5卷 250-267页

作者： Li‑Yong Shen Meng‑Xing Wang hong‑yu ma Yi‑Fei Feng Chun‑Ming yuan School of mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China KLMM Academy of Mathematics and Systems SciencesUniversity of Chinese Academy of SciencesBeijing 100049China

Combining computer-aided design and computer numerical control(CNC)with global technical connections have become interesting topics in the manufacturing industry.A framework was implemented that includes point clouds to workpieces and consists of a mesh generation from geometric data,optimal surface segmentation for CNC,and tool path planning with a certified scallop *** latest methods were introduced into the mesh generation with implicit geometric regularization and total generalized *** the mesh model was obtained,a fast and robust optimal surface segmentation method is provided by establishing a weighted graph and searching for the minimum spanning tree of the graph for extraordinary *** method is easy to implement,and the number of segmented patches can be controlled while preserving the sharp features of the ***,a contour parallel tool-path with a confined scallop height is generated on each patch based on B-spline *** results show that the proposed framework is effective and robust.

关键词： Computer numerical control Mesh reconstruction Mesh segmentation Path planning Scallop height

GPa-level pressure-induced enhanced corrosion resistance in TiZrTaNbSn biomedical high-entropy alloy

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China Foundry 2024年第3期21卷 265-275页

作者： Xiao-hong Wang yu-lei Deng Qiao-yu Li Zhi-xin Xu Teng-fei ma Xing Yang Duo Dong Dong-dong Zhu Xiao-hong Yang Key Laboratory of Air-driven Equipment Technology of Zhejiang Province Quzhou UniversityQuzhou 324000ZhejiangChina School of materials Science and Engineering Taizhou UniversityTaizhou 318000ZhejiangChina

TiZrTaNb-based high-entropy alloys(HEAs)are research frontier of biomedical materials due to their high hardness,good yield strength,excellent wear resistance and corrosion ***,as an essential trace element in the human body that plays a significant role in physiological *** has stable chemical properties and a low elastic *** this study,a new material,TiZrTaNbSn HEAs,was proposed as a potential biomedical *** Ti_(35)Zr_(25)Ta_(15)Nb_(15)Sn_(10)biomedical high-entropy alloys(BHEAs)were successfully prepared through an arc melting furnace and then remelted using a German high-temperature and high-pressure apparatus under GPa-level(4 GPa and 7 GPa).The precipitation behavior of the needle-like HCP-Zr_(5)Sn_(3)phase that precipitates discontinuously at the grain boundary was successfully *** phase constitution,microstructure,and corrosion resistance of the alloy were *** results show that the needle-like HCP-Zr_(5)Sn_(3)phase is eliminated and the(Zr,Sn)-rich nano-precipitated phase is precipitated in the microstructure under high pressure,which leads to the narrowing of grain boundaries and consequently improves the corrosion resistance of the *** addition,the formation mechanisms of(Zr,Sn)-rich nanoprecipitates in BHEAs were *** Zr and Sn dissolve in the matrix due to the effect of high pressure,during the cooling process,they precipitate to form a(Zr,Sn)-rich nano-precipitated phase.

关键词： biomedical HEAs precipitation grain boundary corrosion resistance TiZrTaNbSn

Nuclear phylogenomics of angiosperms and insights into their relationships and evolution

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Journal of Integrative Plant Biology 2024年第3期66卷 546-578页

作者： Guojin Zhang hong ma College of Life Sciences Hunan Normal UniversityChangsha 410081China Department of Biology 510 Mueller LaboratoryHuck Institutes of the Life SciencesThe Pennsylvania State UniversityUniversity ParkPA 16802USA

Angiosperms(flowering plants) are by far the most diverse land plant group with over 300,000 species. The sudden appearance of diverse angiosperms in the fossil record was referred to by Darwin as the “abominable mystery,”hence contributing to the heightened interest in angiosperm evolution. Angiosperms display wide ranges of morphological, physiological,and ecological characters, some of which have probably influenced their species richness. The evolutionary analyses of these characteristics help to address questions of angiosperm diversification and require well resolved phylogeny. Following the great successes of phylogenetic analyses using plastid sequences,dozens to thousands of nuclear genes from next-generation sequencing have been used in angiosperm phylogenomic analyses, providing well resolved phylogenies and new insights into the evolution of angiosperms. In this review we focus on recent nuclear phylogenomic analyses of large angiosperm clades, orders, families,and subdivisions of some families and provide a summarized Nuclear Phylogenetic Tree of Angiosperm Families. The newly established nuclear phylogenetic relationships are highlighted and compared with previous phylogenetic results. The sequenced genomes of Amborella,Nymphaea, Chloranthus, Ceratophyllum, and species of monocots, magnoliids, and basal eudicots, have facilitated the phylogenomics of relationships among five major angiosperms clades. All but one of the 64 angiosperm orders were included in nuclear phylogenomics with well resolved relationships except the placements of several orders. Most families have been included with robust and highly supported placements, especially for relationships within several large and important orders and ***, we examine the divergence time estimation and biogeographic analyses of angiosperm on the basis of the nuclear phylogenomic frameworks and discuss the differences compared with previous analyses. Furthermore,we discuss the implicatio

关键词： angiosperms evolution flowering plants nuclear gene phylogenomics phylogeny

Polypropylene/Silica Nanocomposites in situ Prepared via Sol-Gel Reactions Using Porous Spherical Poly(propylene-g-(styrene-alt-maleic anhydride)) Granules as Reaction Loci

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Chinese Journal of Polymer Science 2015年第12期33卷 1730-1740页

作者： Zhuo Li yu-hong ma 杨万泰 The State Key Laboratory of Chemical Resources Engineering Beijing University of Chemical Technology Key Laboratory of Carbon Fiber and Functional Polymers Ministry of Education Beijing University of Chemical Technology

Using the porous polypropylene （PP） granules consisting of submicroparticles prepared by the reactor granular technology （RGT）, a facile process was developed to synthesize in situ polypropylene/silica nanocomposites where styrene- alt-maleic anhydride copolymers （PSM） were firstly grafted onto both the outer- and the inner-pore surfaces of PP granules via solid-phase grafting polymerization, and then a sol-gel reaction was conducted inside these micro-pores with the carboxyl acid derived from maleic anhydride as catalyst. TEM micrographs demonstrated that the silica nanoparticles obtained by this strategy had a size around 10-20 nm in diameter and uniformly dispersed in the PSM-based nanocomposites. More importantly, the silica nanoparticles could significantly reduce the size of PP spherulites. Consequently, the PP/silica nanocomposites with high transparency and good mechanical performance were achieved.

关键词： Nanocomposites Solid-state polymerization Silica.

High-entropy oxide-supported platinum nanoparticles for efficient hydrogen evolution reaction

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Rare Metals 2024年第4期43卷 1537-1546页

作者： Ming-yu Fan Jia-Jun Wang Jun Zhao hong Zhang Tian-Yi ma Xiao-Peng Han Wen-Bin Hu School of materials Science and Engineering Tianjin Key Laboratory of Composite and Functional Materials Key Laboratory of Advanced Ceramics and Machining TechnologyTianjin UniversityTianjin300350China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou350207China School of Science RMIT UniversityMelbourneVIC3000Australia

High-entropy oxides(HEOs)are a new class of single-phase structures with unique electronic and catalytic properties;therefore,it is worthwhile to explore their applications in *** this study,a Pt/(FeCoNiCrAl)_(3)O_(4)nanohybrid using HEO as a support was developed as an efficient catalyst for the hydrogen evolution reaction(HER).Pt/(FeCoNiCrAl)_(3)O_(4)exhibited high HER activity with a low overpotential of 22 mV at10 ma·cm^(-2),outperforming other binary,ternary,and quaternary *** HER activity of Pt/(FeCoNiCrAl)_(3)O_(4)was higher than that of a commercial Pt/C with a significantly lower Pt *** catalyst exhibited good activity and long-term stability(60 h)in an electrolytic water-splitting *** good activity can be attributed to the fact that the introduction of Pt effectively facilitates electronic interactions between Pt and the *** addition,the HEO substrate was more favorable for dispersing Pt particles,optimizing the electrochemical specific surface area,and significantly reducing the charge resistance of the *** study extends the application of HEOs in electrocatalysis and demonstrates the promising prospects of HEOs as supports for electrocatalysts.

关键词： High-entropy oxides Hydrogen evolution reaction Nanohybrid Water electrolysis

Hydration lubrication modulated by water structure at TiO2–aqueous interfaces

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Friction 2024年第4期12卷 591-605页

作者： Pingsu ma yuan LIU Ke HAN yu TIAN Liran ma State Key Laboratory of Tribology in Advanced Equipment Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China

The nature of solid-liquid interfaces is of great significance in *** advances have been made in lubrication based on hydration ***,a detailed molecular-level understanding is still ***,we investigated water molecule behaviors at the TiO2-aqueous interfaces by the sum-frequency generation vibrational spectroscopy(SFG-VS)and atomic force microscope(AFM)to elucidate the fundamental role of solid-liquid interfaces in *** contributions of water structures and hydration effects were revealed,where water structures played the dominant role in lubrication for TiO2 surfaces of varying hydrophilicity,while hydration effects dominated with the increasing of ion *** lubrication is observed on the initial TiO2 surfaces with strongly H-bonded water molecules compared to the hydrophilic TiO2 surfaces with more disordered *** stable ordered water arrangement with strong hydrogen bonds and the shear plane occurring between the ordered water layer and subsequent water layer may play a significant role in achieving lower *** adsorbed hydrated molecules with the increasing ionic concentration perturb ordered water but lead to the enhancement of hydration effects,which is the main reason for the improved lubrication for both *** work provides more insights into the detailed molecular-level understanding of the mechanism of hydration lubrication.

关键词： hydration lubrication interfacial water structures hydration effects titanium dioxide(TiO2)

Opportunities for production and property research of neutron-rich nuclei around N=126 at HIAF

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Nuclear Science and Techniques 2024年第6期35卷 101-113页

作者： Shao-Bo ma Li-Na Sheng Xue-Heng Zhang Shi-Tao Wang Kai-Long Wang Chun-Wang ma Hool-Jin Ong Zhi-yu Sun Shu-Wen Tang yu-hong yu Xin-Tong Du Xiao-Bao Wei Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Advanced Energy Science and Technology Guangdong Laboratory Huizhou 516000China University of Chinese Academy of Sciences Beijing 100049China College of Physics Henan Normal UniversityXinxiang 453007China Institute of Nuclear Science and Technology Henan Academy of ScienceZhengzhou 450046China Joint-Department for Nuclear Physics Lanzhou University and Institute of Modern PhysicsLanzhou 730000China Research Center for Nuclear Physics Osaka UniversityOsaka 567-0047Japan RIKEN Nishina Center Saitama 351-0198Japan Northwest Normal University Lanzhou 730070China

The study of nuclide production and its properties in the N=126 neutron-rich region is prevalent in nuclear physics and astrophysics *** upcoming High-energy FRagment Separator(HFRS)at the High-Intensity heavy-ion Accelerator Facility(HIAF),an in-flight separator at relativistic energies,is characterized by high beam intensity,large ion-optical acceptance,high magnetic rigidity,and high momentum resolution *** provides an opportunity to study the production and properties of neutron-rich nuclei around N=*** this paper,an experimental scheme is proposed to produce neutron-rich nuclei around N=126 and simultaneously measure their mass and lifetime based on the HFRS separator;the feasibility of this scheme is evaluated through *** results show that under the high-resolution optical mode,many new neutron-rich nuclei approaching the r-process abundance peak around A=195 can be produced for the first time,and many nuclei with unknown masses and lifetimes can be produced with high *** the time-of-flight corrected by the measured dispersive position and energy loss information,the cocktails produced from 208 Pb fragmentation can be unambiguously ***,the masses of some neutron-rich nuclei near N=126 can be measured with high precision using the time-of-flight magnetic rigidity *** indicates that the HIAF-HFRS facility has the potential for the production and property research of neutron-rich nuclei around N=126,which is of great significance for expanding the chart of nuclides,developing nuclear theories,and understanding the origin of heavy elements in the universe.

关键词： HFRS Fragmentation Neutron-rich nuclei around N=126 mass measurement Lifetime