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Rare Metals 2024年第4期43卷 1815-1827页

作者： Sheng-Feng Zhou Yu Long Yan-Liang Yi Cheng Deng Lian-xi Hu Institute of Advanced Wear&Corrosion Resistant and Functional Materials Jinan UniversityGuangzhou510632China Wuhan National Laboratory for Optoelectronics(WNLO) Huazhong University of Science and TechnologyWuhan430074China MOE Key Laboratory of New Processing Technology for Non-Ferrous Metals and Materials Guangxi Key Laboratory of Processing for Non-Ferrous Metals and Featured MaterialsGuangxi UniversityNanning530004China School of Mechatronics Engineering Guangdong Polytechnic Normal UniversityGuangzhou510635China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin150001China

To improve the wear performance of CoCrAlYTa coating,part of the carbon nanotubes(CNTs)chemically reacted with Ta to form reinforcement phase(TaC),while the other CNTs were retained as lubrication ***,the CoCrAlYTa-xCNTs(x=0,1,2,and 4;wt%)composite coatings were prepared by laserinduction hybrid cladding(LIHC),and the microstructure and wear resistance of coatings were systematically *** show that the coatings are mainly composed of TaC,y-(Co,Cr)andβ-(Co,Cr)*** the CNTs content increases from 0 wt%to 4 wt%,the volume fraction of TaC increases from 13.11 vol%to 16.12 vol%.Meanwhile,the nano-hardness ofγ-(Co,Cr)andβ-(Co,Cr)Al are improved from 7.49 and 9.72 to 9.36 and 11.19 GPa,*** a result,the microhardness of coating increases from HV536.25 to HV 738.16,the wear rate decreases from32.4×10^(-3)to 6.1×10^(-3)mg·m^(-1),and the average friction coefficient decreases from 0.55 to *** good wear performance of the coating is attributed to the formation of TaC and the existence of remained CNTs lubricant film.

关键词： Carbon nanotube MCrAlY coating Friction and wear performance Laser-induction hybrid cladding

Experimental investigation on using CO_(2)/H_(2)O emulsion with high water cut in enhanced oil recovery

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Petroleum Science 2024年第2期21卷 974-986页

作者： xi-Dao Wu Peng xiao Bei Liu Guang-Jin Chen Jian-Hua Pang State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China Ocean Intelligence Technology Center Shenzhen Institute of Guangdong Ocean UniversityShenzhen518120GuangdongChina

CO_(2) emulsions used for EOR have received a lot of interest because of its good performance on CO_(2)mobility ***,most of them have been focusing on the high quality CO_(2) emulsion(high CO_(2) fraction),while CO_(2) emulsion with high water cut has been rarely *** this paper,we carried out a comprehensive experimental study of using high water cut CO_(2)/H_(2)O emulsion for enhancing oil ***,a nonionic surfactant,alkyl glycosides(APG),was selected to stabilize CO_(2)/H_(2)O emulsion,and the corresponding morphology and stability were evaluated with a transparent PVT ***,plugging capacity and apparent viscosity of CO_(2)/H_(2)O emulsion were measured systematically by a sand pack displacement apparatus connected with a 1.95-m long capillary ***,a high water cut(40 vol%) CO_(2)/H_(2)O emulsion was selected for flooding experiments in a long sand pack and a core sample,and the oil recovery,the rate of oil recovery,and the pressure gradients were *** results indicated that APG had a good performance on emulsifying and stabilizing CO_(2) *** inversion from H_(2)O/CO_(2) emulsion to CO_(2)/H_(2)O emulsion with the increase in water cut was ***_(2)/H_(2)O emulsions with lower water cuts presented higher apparent viscosity,while the optimal plugging capacity of CO_(2)/H_(2)O emulsion occurred at a certain water ***,the displacement using CO_(2)/H_(2)O emulsion provided 18.98% and 13.36% additional oil recovery than that using pure CO_(2) in long sand pack and core tests,*** work may provide guidelines for EOR using CO_(2) emulsions with high water cut.

关键词： CO_(2)/H_(2)O emulsion High water cut CO_(2) mobility control Enhanced oil recovery

Topological superconductors with spin-triplet pairings and Majorana Fermi arcs

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Chinese Physics B 2024年第8期33卷 453-458页

作者：黄石罗熙 College of Science University of Shanghai for Science and TechnologyShanghai 200093China

We construct a three-dimensional topological superconductor Bogoliubov–de Gennes(BdG)Hamiltonian with the normal state being a three-dimensional topological *** introducing inter-orbital spin-triplet pairings term△3,there are topological Majorana nodes in the bulk and they are connected by Majorana Fermi arcs on the surface,similar to the case of Weyl ***,by adding an inversion-breaking term to the normal state,momentum-independent pairing terms with different parities can coexist in the Bd G Hamiltonian,which creates more Majorana modes similar to Andreev bound states and a richer phase diagram.

关键词： topological surface states topological superconductors topological nodes Weyl points Majorana Fermi arcs

A unified Minorization-Maximization approach for estimation of general mixture models

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 343-362页

作者： HUANG xi-fen LIU Deng-ge ZHOU Yun-peng ZHU Fei School of Mathematics Yunnan Normal UniversityKunming 650092China Department of Statistics and Actuarial Science The University of Hong KongHong KongChina

The mixed distribution model is often used to extract information from heteroge-neous data and perform modeling *** the density function of mixed distribution is complicated or the variable dimension is high,it usually brings challenges to the parameter es-timation of the mixed distribution *** application of MM algorithm can avoid complex expectation calculations,and can also solve the problem of high-dimensional optimization by decomposing the objective *** this paper,MM algorithm is applied to the parameter estimation problem of mixed distribution *** method of assembly and decomposition is used to construct the substitute function with separable parameters,which avoids the problems of complex expectation calculations and the inversion of high-dimensional matrices.

关键词： MM algorithm mixed distribution model parameter estimation assembly decomposition tech-nology parameter separation

Tree‑Inspired Structurally Graded Aerogel with Synergistic Water,Salt,and Thermal Transport for High‑Salinity Solar‑Powered Evaporation

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Nano-Micro Letters 2024年第11期16卷 19-37页

作者： xiaomeng Zhao Heng Zhang Kit‑Ying Chan xinyue Huang Yunfei Yang xi Shen Department of Aeronautical and Aviation Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong SARPeople’s Republic of China Research Institute for Sports Science and Technology The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong SARPeople’s Republic of China Research Institute for Advanced Manufacturing The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong SARPeople’s Republic of China

Solar-powered interfacial evaporation is an energy-efficient solution for water *** requires solar absorbers to facilitate upward water transport and limit the heat to the surface for efficient ***,downward salt ion transport is also desired to prevent salt ***,achieving simultaneously fast water uptake,downward salt transport,and heat localization is challenging due to highly coupled water,mass,and thermal ***,we develop a structurally graded aerogel inspired by tree transport systems to collectively optimize water,salt,and thermal *** arched aerogel features root-like,fan-shaped microchannels for rapid water uptake and downward salt diffusion,and horizontally aligned pores near the surface for heat localization through maximizing solar absorption and minimizing conductive heat *** structural characteristics gave rise to consistent evaporation rates of 2.09 kg m^(-2) h^(-1) under one-sun illumination in a 3.5 wt%NaCl solution for 7 days without *** in a high-salinity solution of 20 wt%NaCl,the evaporation rates maintained stable at 1.94 kg m^(-2) h^(-1) for 8 h without salt crystal *** work offers a novel microstructural design to address the complex interplay of water,salt,and thermal transport.

关键词： Composite aerogel Graded structure Solar-powered evaporation Thermal insulation Salt rejection

Comparison of irradiation-induced void formations in tungsten with equiaxed and columnar structures

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Tungsten 2024年第4期6卷 794-805页

作者： Liu xi Jia-Jun Zhao Ji-Jun Zhao Yuan-Yuan Wang Key Laboratory of Materials Modification by Laser Ion and Electron Beams(Ministry of Education) Dalian University of Technology

Tungsten(W) has been received much attention,since it is regarded as one of the most promising plasma facing materials for fusion *** are two typical morphologies of unirradiated polycrystalline W,which have the equiaxed and columnar grains,***,the role of arrangement of grain boundary(GB) in absorbing irradiation-generated point defects is still waiting to be *** current investigation,irradiation-induced void formations in W with equiaxed and columnar microstructures are predicted,respectively,using the developed phase-field *** significant kinetic behavior,such as the generation and annihilation of point defects and the interaction between point defects and GB,is reasonably *** density,size and porosity of void formed in these two microstructures are examined and analyzed according to the effects of GB ratio,temperature and damage *** analytical results show that higher GB ratio can effectively reduce void porosity,and the columnar-grained structure has better irradiation resistance than that of the equiaxed one in the case of small grain *** importantly,the predicted void sizes changed with temperature and damage rate agree well with the experimentally measured *** work has a more beneficial contribution to the microstructural improvement of International Thermonuclear Experimental Reactor-grade W.

关键词： Grain morphology Irradiation-induced void Phase-field Tungsten

Rational cathode configuration with bilayer membranes to engineer current-collector-free high-areal-sulfur lithium-sulfur batteries

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Nano Research 2024年第6期17卷 5224-5232页

作者： Jianmei Han Hua Zhang Peng Wang Ning Song Xuguang An Baojuan xi Shenglin xiong College of Chemistry and Chemical Engineering Taishan UniversityTai’an 271021China Key Laboratory of the Colloid and Interface Chemistry Ministry of Educationand School of Chemistry and Chemical EngineeringShandong UniversityJinan 250100China School of Mechanical Engineering Chengdu UniversityChengdu 610106China

The application of light-weight current collectors is preferred because of the increased energy density of the *** it in mind,the cathode is designed with self-made paperlike memberane as current collector coupled with another interlayer to enable the high-energy-density lithium-sulfur *** a facile and green step-by-step methodology,the hybrid membrane is finalized successfully,consisting of reduced graphene oxide sheets covering paper-derived carbon(GPC)bearing Fe@Fe2O3 and Fe1−xS@Fe2O3 core-shell nanoparticles(FeFeO/FeSFeO@GPC).The film works as the current collector and interlayer simultaneously considering the porous and conductive *** demonstrated by the electrochemical testing,the FeFeO/FeSFeO@GPC hybrid cell exhibits attractive cycling stability and superior rate *** cell configuration and structural/composition merits of FeFeO/FeSFeO@GPC film facilitate the faster reaction kinetics,conducive to the improvement of capacity *** view of the effective cathode design,the areal sulfur loading is increased to 10.46 mg·cm^(−2)and a reversible capacity of 6.67 mAh·cm^(−2)can be retained after 60 cycles at 0.1 C.

关键词： light-weight self-made current collector core-shell high-areal-sulfur lithium-sulfur batteries

Phosphotungstic acid immobilized on amino-functionalized TS-1 zeolite as a solid acid catalyst for the synthesis of tributyl citrate

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Chinese Journal of Chemical Engineering 2024年第6期70卷 199-210页

作者： Pei Li Bianfang Shi Junyao Shen Ran Cui Wenze Guo Ling Zhao Zhenhao xi State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237China

The amino-functionalization of TS-1 zeolite followed by immobilization of phosphotungstic acid(HPW)was presented to prepare a strong solid acid catalyst for the synthesis of bio-based tributyl citrate from the esterification of citric acid and n-butanol.γ-Aminopropyltriethoxysilane(APTES)was first grafted on the TS-1 zeolite via the condensation reactions with surface hydroxyl groups,and subsequently the HPW was immobilized via the reaction between the amino groups and the protons from HPW-forming strong ionic *** Keggin structure of HPW and MFI topology of TS-1 zeolite were well maintained after the *** amino-functionalization generated abundant uniformly distributed active sites on TS-1 for HPW immobilization,which promoted the dispersity,abundance,as well as the stability of the acid *** tetrahedrally coordinated framework titanium and non-framework titania behaved as weak Lewis acid sites,and the protons from the immobilized HPW acted as the moderate or strong Brønsted acid *** optimized TBC yield of 96.2%(mol)with a conversion of-COOH of 98.1%(mol)was achieved at 150℃for 6 h over the HPW immobilized on amino-functionalized *** catalyst exhibited good stability after four consecutive reaction runs,where the activity leveled off at still a relatively high level after somewhat deactivation possibly caused by the leaching of a small portion of weakly anchored APTES or HPW.

关键词： Amino-functionalization Phosphotungstic acid TS-1 zeolite Esterification Tributyl citrate

Triboelectric nanogenerator integrated with a simple controlled switch for regularized water wave energy harvesting

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Nano Research 2024年第8期17卷 7585-7592页

作者： Hongbo Yang xi Liang Junwu Kan Zhong Lin Wang Tao Jiang Zhanyong Hong College of Engineering Zhejiang Normal UniversityJinhua 321004China Beijing Key Laboratory of Micro-Nano Energy and Sensor Center for High-Entropy Energy and SystemsBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 101400China The Beijing Key Laboratory for Nano-Photonics and Nano-Structure Department of PhysicsCapital Normal UniversityBeijing 100048China Guangzhou Institute of Blue Energy Guangzhou 510555China Georgia Institute of Technology AtlantaGA 30332-0245USA Yonsei Frontier Lab Yonsei UniversitySeoul 03722Republic of Korea

Ocean is full of low-frequency,irregular,and widely distributed wave energy,which is suitable as the energy source for maritime Internet of Things(IoTs).Utilizing triboelectric nanogenerators(TENGs)to harvest ocean wave energy and power sensors is proven to be an effective ***,in random ocean waves,the irregular electrical energy output by general TENGs restricts the *** present,achieving regularized water wave energy harvesting relies on rather complex mechanical structure designs,which is not conducive to *** this work,we proposed a novel mechanical controlled TENG(MCTENG)with a simple controlled switch to realize the regularization *** structural parameters of the MC-TENG are optimized,and the optimal output voltage,output current,and transferred charge respectively reach 1684.2 V,85.4μA,and 389.9 nC,generating a peak power density of 38.46 W·m^(−3)·Hz^(−1).Under real water wave environment,the output of the MC-TENG is regularized and keeps stable regardless of any wave ***,the potential applications of the MC-TENG are demonstrated in powering environmental temperature,humidity,and wind speed *** work renders a simple approach to achieve effective regularized ocean wave energy harvesting,promoting the TENG industrialization toward practical application of maritime IoTs.

关键词： water wave energy harvesting triboelectric nanogenerators random excitation mechanical control regular output

A Brief Overview of the Development and Significance of Modern Scientific Medicine in China:Take Chinese Academy of Medical Science and Peking Union Medical College as an Example

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Chinese Medical Sciences Journal 2024年第2期39卷 140-143页

作者： Pu-An Cui Zhe-xi Gong Zhong He School of Humanities and Social Sciences Chinese Academy of Medical Science&Peking Union Medical CollegeBeijing 100730China

Since the early 20th century,China has gradually established a clinical,educational,and research system centered around modern scientific medicine,which has now become the dominant force in China's medical and health system and services,with the construction and development of the Chinese Academy of Medical Sciences and Peking Union Medical College as the most prominent *** scientific medicine in the new era requires close cooperation across multiple disciplines and fields to build a high-quality and efficient medical and health service *** also involves combining the excellent traditional Chinese culture with Western medicine to explore a unique path of modern scientific medicine with Chinese characteristics.

关键词： modern scientific medicine cultural confidence multiple view