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Journal of Magnesium and Alloys 2023年第7期11卷 2404-2428页

作者： Y.Yue S.L.yang c.c.Wu J.f.Nie Department of Materials Science and Engineering Monash UniversityVictoria 3800Australia

An unusual f_(3)basal stacking fault resulting from twin-dislocation interaction in magnesium is observed in molecular dynamics *** f_(3)fault is produced in the twin lattice from the interaction between a migrating(1012)twin boundary and a partial dislocation of either a prismaticc>edge,or a prismaticc+a>mixed dislocation in the *** condition is that the partial dislocation needs to have a negative sign and lie on a plane intersecting a compression site of the twin *** f_(3)fault can also be generated when a positive basalmixed dislocation in the twin lattice,with slip plane intersecting a compression site of the twin boundary,interacts with a basal-prismatic twinning *** f_(3)fault comprises two I_(1) faults that have the same character but are separated by two basal *** has one end connected to the twin boundary,and the other end bounded by a lattice defect with a Burgers vector identical to that of a 30°Shockley partial *** formation frequency of the f_(3)fault is higher at a lower shear stress(below∼400 MPa)and/or a lower temperature(100 K and 200 K).The f_(3)fault can decompose into a glissile 30°Shockley and a T_(2) fault at a temperature above∼400 *** relationships between the f_(3)fault and other types of basal stacking faults such as I_(2),T_(2) or paired I_(1) faults that are separated by multiple basal layers are discussed.

关键词： Magnesium Basal stacking fault f3 fault Twin-dislocation interactions

The coal cleat system:A new approach to its study

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Journal of Rock Mechanics and Geotechnical Engineering 2014年第3期6卷 208-218页

作者： c.f. Rodrigues c. Laiginhas M. fernandes M.J. Lemos de Sousa M.A.P. Dinis fernando Pessoa University Porto 4249-004 Portugal Lisbon Portugal Porto Portugal Lisbon Academy of Sciences 1249-122 Lisboa Portugal

After a general analysis regarding the concept of coal ＂cleat system＂, its genetic origin and practical applications to coalbed methane （cBM） commercial production and to c02 geological sequestration projects, the authors have developed a method to answer, quickly and accurately in accordance with the industrial practice and needs, the following yet unanswered questions：（1） how to define the spatial orientation of the different classes of cleats presented in a coal seam and （2） how to determine the frequency of their connectivites. The new available and presented techniques to answer these questions have a strong computer based tool （geographic information system, GIS）, able to build a complete georeferentiated database, which will allow to three-dimensionally locate the laboratory samples in the coalfield. It will also allow to better understand the coal cleat system and consequently to recognize the best pathways to gas flow through the coal seam. Such knowledge is considered crucial for understanding what is likely to be the most efficient opening of cleat network, then allowing the injection with the right spatial orientation, of pressurized fluids in order to directly drain the maximum amount of gas flow to a cBM exploitation well. The method is also applicable to the cO2 geological sequestration technologies and operations corresponding to the injection of cO2 sequestered from industrial plants in coal seams of abandoned coal mines or deep coal seams.

关键词： coalbed methane (cBM)coal cleat systemcoal seamGeographic information system (GIS)Gas flowc02 geological sequestration

constructing Donor–Acceptor‑Linked c.f. Electrolytes to Regulate Electron Density and Accelerate the Li^(+)Migration in Quasi‑Solid‑State Battery

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Nano-Micro Letters 2025年第1期17卷 456-471页

作者： Genfu Zhao Hang Ma conghui Zhang Yongxin yang Shuyuan Yu Haiye Zhu Yongjiang Sun Hong Guo School of Materials and Energy International Joint Research Center for Advanced Energy Materials of Yunnan ProvinceYunnan UniversityKunming 650091People’s Republic of China Yunnan Yuntianhua co. LtdR&D CenterKunming 650228People’s Republic of China Southwest United Graduate School Kunming 650091People’s Republic of China

Regulation the electronic density of solid-state electrolyte by donor–acceptor(D–A)system can achieve highly-selective Li^(+)transportation and conduction in solid-state Li metal *** study reports a high-performance solid-state electrolyte thorough D–A-linked covalent organic.f.ameworks(c.f.)based on intramolecular charge transfer *** other reported c.f.ased solid-state electrolyte,the developed concept with D–A-linked c.f. not only achieves electronic modulation to promote highly-selective Li^(+)migration and inhibit Li dendrite,but also offers a crucial opportunity to understand the role of electronic density in solid-state Li metal *** introduced strong electronegativity f-based ligand in c.f.electrolyte results in highlyselective Li^(+)(transference number 0.83),high ionic conductivity(6.7×10^(-4)S cm^(−1)),excellent cyclic ability(1000 h)in Li metal symmetric cell and high-capacity retention in Li/LifePO_(4)cell(90.8%for 300 cycles at 5c)than substituted c-and N-based *** is ascribed to outstanding D–A interaction between donor porphyrin and acceptor f atoms,which effectively expedites electron transferring from porphyrin to f-based ligand and enhances Li^(+)***,we anticipate that this work creates insight into the strategy for accelerating Li^(+)conduction in high-performance solid-state Li metal batteries through D–A system.

关键词： Electronic modulation engineering Donor-acceptor-linked covalent organic.f.ameworks Quasi-solid-state Li metal battery

fISH ASSEMBLAGE RESPONSES TO DIffERENT SEcONDARY cHANNEL DESIGNS IN THE LOWER MISSISSIPPI RIVER,U.S.A.:A TEMPLATE fOR RIVER RESTORATION

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水生生物学报 2018年第6期42卷 1089-1106页

作者： KAISER Joseph E. SMITH Shannon c.f. ScHRAMM Jr.,HAROLD L. EGGLETON Michael A. Department of Aquaculture and fisheries University of Arkansas at Pine Bluff1200 N.UniversityMail Slot 4912Pine BluffArkansas 71601U.S.A U.S.Geological Survey Mississippi Cooperative Fish and Wildlife Research UnitMississippi State University

The lower Mississippi River(LMR) has been heavily modified for multiple human purposes such as navigation, flood control, and bank stabilization. However, the LMR simultaneously supports a diverse fish fauna that includes recreational and commercial fisheries. Due to river training and diversion structures constructed during the past 80 years, the historic characteristics of the LMR have been drastically altered and have likely influenced fishes and fisheries in the system. One common restoration measure used throughout the LMR has been to "notch" wing-dike structures that close secondary(side) river channels. Dike notching allows year-round flows through secondary channels, which enhances habitat diversity and promotes biological productivity at the ecosystem scale. Although notching is presumed good for LMR fishes and other biota, few studies have examined its effects on fish assemblages. In this study, fish assemblages were sampled at seven LMR secondary channels spanning from river kilometer(rkm) 628(Louisiana-Mississippi, U.S.A.) upstream to rkm 1504(Missouri-Kentucky, U.S.A.). four secondary channels were termed "permanent"(i.e.,with notched dikes) while three secondary channels were termed "temporary"(i.e., without notched dikes).fishes were sampled by boat-mounted electrofishing conducted during falling and low stages from1995—1997. fish assemblages differed between permanent and temporary secondary channels, and varied somewhat between falling and low stages. Gizzard shad(Dorosoma cepedianum), threadfin shad(D. petenense), and white bass(Morone chrysops) demonstrated consistent preferences for low-current conditions associated with temporary secondary channels. conversely, blue catfish(Ictalurus furcatus), flathead catfish(Pylodictis olivaris), and freshwater drum(Aplodinotus grunniens) were more associated with permanent secondary channels. future restoration strategies in the LMR should consider dike notching and resultant maintenance of permanent seconda

关键词： Mississippi River Secondary channels Dikes fish assemblages River restoration River rehabilitation

SOLIDIfIcATION MEcHANISM Of UNDERcOOLEDSINGLE PHASE ALLOYS

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Acta Metallurgica Sinica(English Letters) 1998年第2期11卷 100-106页

作者： J.f.Li G.c.yang Y.H.Zhou Northwestern Polytechnical Univ Xi'an China

The solidification behavior of bulk undercooled Ni50cu50 alloy was systematically investigated. Double recalescences were discovered for the first time in a single phase Ni-cd alloy, in which there is no solid phase transition at elevated temperature. When the alloy melt was undercoolcd below the solidus temperature, the effect of nonequilibrium solidification could make the solid with the norminal composition c0 of the alloy nucleate and grow till tempemture approached To (the temperuture at which the free enengies of solid and liquid with c0 are equal). following it, the nucleation and growth of the solid with more high melting point component were required, so the secondary recalescence took place. The concentration distribution in crystals was also analysed.

关键词： undercooled Ni-cu alloy secondary recalescence solidification mechanism

In Vitro Evaluation of the feasibility of commercial Zn Alloys as Biodegradable Metals

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Journal of Materials Science & Technology 2016年第9期32卷 909-918页

作者： c.Wang H.T.yang X.Li Y.f.Zheng Department of Interventional Radiology and Vascular Surgery Peking University Third Hospital Department of Materials Science and Engineering College of Engineering Peking University

In this work, three widely used commercial Zn alloys （ZA4-1, ZA4-3, ZA6-1 ） were purchased and pre- pared by hot extrusion at 200℃. The microstructure, mechanical properties, corrosion behaviors, biocompatibility and hemocompatibility of Zn alloys were studied with pure Zn as control, commercial Zn alloys demonstrated increased strength and superb elongation compared with pure Zn. Accelerated corrosion rates and uniform corrosion morphologies were observed in terms of commercial Zn alloys due to galvanic effects between Zn matrix and α-Al phases. 100% extracts of ZA4-1 and ZA6-1 alloys showed mild cytotoxicity while 50% extracts of all samples displayed good biocompatibility. Retardant cell cycle and inhibited stress fibers expression were observed induced by high concentration of Zn^2＋ releasing during corrosion. The hemolysis ratios of Zn alloys were lower than 1% while the adhered platelets showed slightly activated morphologies. In general, commercial Zn alloys possess promising mechanical properties, appropriate corrosion rates, significantly improved biocompatibility and good hemocompatibility in comparison to pure Zn. It is feasible to develop biodegradable metals based on commercial Zn alloys.

关键词： commercial Zn alloys Biodegradable metals Mechanical properties corrosion behaviors cytotoxicity Hemocompatibility

Measurement of Monochromatic Emissivity of cement clinker with Various fe_2O_3 content at High Temperature

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Journal of Thermal Science 1996年第2期5卷 128-131页

作者： Z.J. Ye c.f. Ma S.Y. Huang(Beijing Polytechnic University, Beijing 100022, china) Beijing Polytechnic University Beijing China

An application of the optical pyrometer is studied for measuring monochromatic emissivities of cement clinker with various fe2O3 *** idea of using “brightness temperature”is introduced into the emissivity measurement. In this method, there is no need for measuring an actual temperature of sample surfaces, only with determining both brightness temperatures of a sample and a blackbody can the required emissivity be evaluated according to Wien’s radiation law. In practice, the cement clinker is regarded as a greybody, the monochromatic emissivity is approximately equal to the total emissivity, so a single-colour optical pyrometer is applied for this purpose. Test measurements are carried out on 10 kinds of cement clinkers. Experimental data are treated by the least square method. As a result, the emissivity variation with temperature at a certain fe2O3 content is quite well represented by εn=α+bT. furthermore, this work first reported that the emissivities of cement clinker change considerably with fe2O3 contents. In multiple cement production this conclusion is very important.

关键词： monochromatic emissivity brightness temperature cement clinker blackbody radiation

Interface engineering of plasmonic induced fe/N/c.f.catalyst with enhanced oxygen catalysis performance for fuel cells application

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Nano Research 2022年第3期15卷 2138-2146页

作者： Xue Yin Ligang feng Wen yang Yuanxi Zhang Haiyan Wu Le yang Lei Zhou Lin Gan Shaorui Sun Key Laboratory of cluster Science of Ministry of Education Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion MaterialsSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China School of chemistry and chemical Engineering Yangzhou UniversityYangzhou 225002China Institute of Materials Research Shenzhen Geim Graphene CenterTsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China Beijing Key Laboratory for Green catalysis and Separation College of Environmental and Energy EngineeringBeijing University of TechnologyBeijing 100124China

The low intrinsic activity of fe/N/c oxygen catalysts restricts their commercial application in the fuel cells technique;herein,we demonstrated the interface engineering of plasmonic induced fe/N/c.f.catalyst with primarily enhanced oxygen reduction performance for fuel cells *** strong interaction between f and fe-N4 active sites modifies the catalyst interfacial properties as revealed by X-ray absorption structure spectrum and density functional theory calculations,which changes the electronic structure of fe-N active site resulting from more atoms around the active site participating in the reaction as well as super-hydrophobicity from c.f.covalent *** hybrid contribution from active sites and carbon support is proposed to optimize the three-phase microenvironment efficiently in the catalysis electrode,thereby facilitating efficient oxygen reduction *** catalytic performance for oxygen reduction and fuel cells practical application catalyzed by fe/N/c.f.catalyst is thus verified,which offers a novel catalyst system for fuel cells technique.

关键词： interface engineering fe/N/c catalyst cf_(4)plasma treatment three-phase microenvironment proton exchange membrane fuel cells

characterization of high-pressure die-cast hypereutectic Al-Si alloys based on microstructural distribution and fracture morphology

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Journal of Materials Science & Technology 2019年第6期35卷 1099-1107页

作者： X.Y. Jiao J. Wang c.f. Liu Z.P. Guo G.D. Tong S.L. Ma Y. Bi Y.f. Zhang S.M. Xiong School of Materials Science and Engineering Tsinghua University Beijing 100084 China State Key Laboratory of Automobile Safety and Energy Tsinghua University Beijing China china fAW foundry co. Ltd. Changchun 130011. China

The fracture behavior of high-pressure die-cast hypereutectic(HPDc) Al-Si alloys was investigated using a high-resolution laboratory cT and synchrotron X-ray tomography with a particular focus on the influence of HPDc microstructure. Results showed that microstructure of the alloy was mainly comprised of primary silicon particles(PSPs), Al dendrites, cu-rich phases and pores. Most of the coarse PSPs, cu-rich phases and pores were located in the center of the specimen. The rapid solidification of HPDc led to a heterogeneous microstructural feature. Elemental cu was enriched in the frontiers of solid-liquid interface, causing the formation of large size dendritic arms. The pores were formed in the interdendrites which endured high stress intensity under high applied stress. Microcracks were originated from pores and further connected cu-rich phases causing intergranular fracture. PSPs worked as obstacles causing piling-up dislocations in the phase interface. In the regions where large size of PSPs enriched in, PSPs ruptured rather than debonded from matrix, indicating transgranular fractures of PSPs. Microcracks originated around pores and PSPs tended to converge on the main cracks to decrease the energy required for crack propagation.

关键词： Hypereutectic Al-Si alloy Primary silicon particles Porosity fracture morphology High pressure die casting