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Decagonal quasicrystal growth in the undercooled A172Ni12co16 alloy

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Decagonal quasicrystal growth in the undercooled A172Ni12Co1...

A review on the generation, determination and mitigation of Urban Heat Island

作者： y.c. liu~*, X.F. Guo, J.H. yang, G.c. yang, y.H. Zhou State Key Lab of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072. People’s Republic of china

High undercooling of the single-phase decagonal quasicrystal alloy AlNico was achieved by.c.clically superheating the melt in a containerless electromagnetic levitation apparatus. The maximum undercooling of it was up to 368 K. XRD, TEM, SEM and optical microscopy techniques were adopted to investigate the microstructure and identify the phase composition, respectively. A distinct roughening transition was detected in the undercooled samples with the undercooling increasing. The decagonal quasicrystal phase in samples with small undercoolings showed a facet morphology and grew in a lateral growth mode below the roughening transition undercooling point, △T = 64 K. Then the decagonal phase took on an equiaxed structure and indicated a continuous growth pattern. The roughening transition was caused by a sudden change of the growth direction from the two-fold axis normal to plane (00002) to the ten-fold axis in the undercooled melt. Toner’s surface dynamics models of growing three-dimensional quasicrystal and BcT growth model in the undercooled melt (proposed by Boettinger, coriel and Trivedi) were adopted to explain the roughening transition phenomenon. 2000 Elsevier Science B.V. All fights reserved.

关键词： Decagonal quasicrystal Lateral growth continuous growth Melt undercooling

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Journal of Environmental Sciences 2008年第1期20卷 120-128页

作者： RIZWAN Ahmed Memon DENNIS y.c. Leung liu chunho Department of Mechanical Engineering the University of Hong Kong Hong Kong China.

Urban Heat Island （UHI） is considered as one of the major problems in the 21st century posed to human beings as a result of urbanization and industrialization of human civilization. The large amount of heat generated from urban structures, as they.c.nsume and re-radiate solar radiations, and from the anthropogenic heat sources are the main causes of UHI. The two heat sources increase the temperatures of an urban area as compared to its surroundings, which is known as Urban Heat Island Intensity （UHII）. The problem is even worse in cities or metropolises with large population and extensive economic activities. The estimated three billion people living in the urban areas in the world are directly exposed to the problem, which will be increased significantly in the near future. Due to the severity of the problem, vast research effort has been dedicated and a wide range of literature is available for the subject. The literature available in this area includes the latest research approaches, concepts, methodologies, latest investigation tools and mitigation measures. This study was carded out to review and summarize this research area through an investigation of the most important feature of UHI. It was concluded that the heat re-radiated by the urban structures plays the most important role which should be investigated in details to study urban heating especially the UHI. It was also concluded that the future research should be focused on design and planning parameters for reducing the effects of urban heat island and ultimately living in a better environment.

关键词： urban heat island (UHI) urbanization temperature rise mitigation

Rational modulation of fluorophosphate cathode by anionic groups to reduce the polarization behavior for fast-charging sodium-ion batteries

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Journal of Energy.c.emistry 2025年第1期100卷 509-521页

作者： Xinyuan Wang Fan Zhang Xingyu Zhou Qian Wang changyu liu yangyang liu Hui Wang Xiaojie liu Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry & Materials Science Northwest University

Na3V2（PO4）2O2F （VP） is recognized as a promising cathode material for sodium-ion batteries due to its stable structural framework and high specific *** functional theory （DFT） and finite element simulations show that incorporating SO42-into VP decreases its band gap,lowers the migration energy barrier,and ensures a uniform Na+concentration gradient and stress distribution during charge and discharge ***,the average Na+diffusion coefficient of Na3V2（PO4）1.95（SO4）0.05O2F（VPS-1） is roughly double that of VP,leading to enhanced rate capability (80 c,75.5 mAh g-1) and cycling stability (111.0 mAh g-1capacity after 1000 cycles at 10 c current density) for ***-1 exhibits outstanding fast-charging capabilities,achieving an 80%state of charge in just 8.1 *** assembled VPS-1//SbSn/NPc full cell demonstrated stable cycling over 200 cycles at a high 5 c current,maintaining an average coulombic efficiency of 95.35%.

关键词： Anionic group modulation Polarization behavior Fast-charging Sodium-ion battery Fluorophosphate cathode

High-Temperature Oxidation Behavior of a Ni-cr-W-Al Alloy

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Journal of Materials Science & Technology 2011年第9期27卷 841-845页

作者： y.c. Ma X.J. Zhao M. Gao K. liu Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

A study was conducted to examine the isothermal oxidation behavior of a new Ni-cr-W-AI alloy in air at 1250℃ with different time. Oxidation kinetics was determined from weight-change measurements. The microstructure and composition of the oxide scale were investigated by means of scanning electron microcopy and X-ray diffraction. The results showed that the oxide scales of the alloy were a compact and continuous outer cr2O3 and Nicr2O4 layer and an inner Al2O3 layer that was in dendrite shape. Oxides scales with good adherence were formed on the surface of the alloy, which made the alloy perform excellent high-temperature oxidation resistance.

关键词： Oxidation kinetics Oxide scale High-temperature oxidation resistance

Low-cost and fluoride-free synthesis of MFI zeolite nanosheets with enhanced stability for benzene alkylation with ethanol

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Journal of Energy.c.emistry 2025年第1期100卷 458-468页

作者： Peng Zhu cun liu yiren yu Guoshu Gao yumeng Zhao Xiongfu Zhang Guodong liu Guohui yang State Key Laboratory of Fine chemicals School of Chemical Engineering Dalian University of Technology State Key Laboratory of catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented *** obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully.c.rried out in a 3 L highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis.

关键词： MFI zeolite ZSM-5 Nanosheets Scale-up synthesis Aromatic alkylation

Synthesis of faveolate open-structured Ru-N/c cathode catalyst with high bifunctional activity for rechargeable quasi-solid-state Li-O_(2)batteries

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Nano Research 2025年第1期18卷 351-361页

作者： Tie liu School of chemistry and chemical Engineering Heze UniversityHeze 274015China

The constituents and geometric design of cathodic electrocatalyst to achieve high activity and durability are effective but challenging for the development of high-performance Li-O_(2)*** study employs a mild solution precipitation method followed by thermolysis to construct a faveolate open-structured Ru-N/c matrix with a loosely braided network morphology as a bifunctional *** details prove that this hybrid structure is composed of ultrafine Ru globular nanoparticles(ca.2 nm)coated with an N-enriched carbon film and exhibits a valuable beehive through-hole character for rapid mass transport during oxygen redox *** synergistic effect of open-structured and reticular network matrix with metal-N4 coordination induces asymmetric charge distributions with moderate adsorption/desorption behaviour with oxygen ***,this particular Ru-N/c matrix cathode provides a promising Li_(2)O_(2)accommodation space and exhibits superior electrochemical performance in terms of a positive discharge plateau and low charge ***,the assembled batteries also present a high discharge capacity and a long cycle life(exceeding 283 cycles).The density functional theory(DFT)calculations also corroborate the assertion that the Ru-N/c catalyst exhibits robust electronic coupling transfer and superior bifunctional *** such,our work demonstrates that this type of open-structured Ru-N/c matrix is promising for fabricating high-performance quasi solid-state Li-O_(2)batteries.

关键词： ruthenium nitride nitrogen-doped carbon electrocatalyst Li-O_(2)battery

Multi-layer multi-pass friction rolling additive manufacturing of Al alloy:Toward complex large-scale high-performance components

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 425-438页

作者： Haibin liu Run Hou chenghao Wu Ruishan Xie Shujun chen college of Mechanical&Energy Engineering Beijing University of TechnologyBeijing 100124China chongqing Research Institute of Beijing University of Technology Chongqing 401121China

At present,the emerging solid-phase friction-based additive manufacturing technology,including friction rolling additive man-ufacturing(FRAM),can only manufacture simple single-pass *** this study,multi-layer multi-pass FRAM-deposited alumin-um alloy samples were successfully prepared using a non-shoulder tool *** material flow behavior and microstructure of the over-lapped zone between adjacent layers and passes during multi-layer multi-pass FRAM deposition were studied using the hybrid 6061 and 5052 aluminum *** results showed that a mechanical interlocking structure was formed between the adjacent layers and the adja-cent passes in the overlapped center *** friction and rolling of the tool head led to different degrees of lateral flow and plastic deformation of the materials in the overlapped zone,which made the recrystallization degree in the left and right edge zones of the over-lapped zone the highest,followed by the overlapped center zone and the non-overlapped *** tensile strength of the overlapped zone exceeded 90%of that of the single-pass deposition *** is proved that although there are uneven grooves on the surface of the over-lapping area during multi-layer and multi-pass deposition,they.c.n be filled by the flow of materials during the deposition of the next lay-er,thus ensuring the dense microstructure and excellent mechanical properties of the overlapping *** multi-layer multi-pass FRAM deposition overcomes the limitation of deposition width and lays the foundation for the future deposition of large-scale high-performance components.

关键词： aluminum alloy additive manufacturing solid-state friction stir welding multi-layer multi-pass

Effects of Boron Addition on Grain Refinement in TiAl-based Alloys

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Journal of Materials Science & Technology 2010年第7期26卷 639-647页

作者： W.D. Wang,y.c. Ma,B. chen,M. Gao,K. liu and y.y. Li Institute of Metal Research,chinese Academy of Sciences,Shenyang 110016,china Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Solid state phase transformation characteristics of the body.c.ntred β（Ti） into the hexagonal closed packed α（Ti） in Ti45AI8Nb-（0, 0.3, 0.5 and 0.8 at. pct） B alloys were investigated by heat treatment to clarify γ/α2 lamellar microstructure refinement induced by B addition. Experimental results confirmed two kinds of boron-reduced grain refinement mechanisms through refining either/β phase then α phase （β-refinement） or α phase directly （α-refinement） to refine lamellar microstructure at room temperature; however, the role of α-refinement dominated the as-cast alloy. It was also found that during the lamellar microstructure refinement β-refinement the convoluted flake over β-refinement in Ti45Al8NbxB and plate-like borides along β grain boundaries assisted nucleation of α phase, and the particle-like borides nearβ grain boundaries impeded α phase growth.

关键词： Titanium aluminides Phase transformation Microstructure

Highly.c.nductive and stable iodine doped argyrodite electrolyte for all-solid-state lithium batteries

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Journal of Energy.c.emistry 2025年第1期100卷 50-58页

作者： Gaozhan liu Jing Zhang Jing yang Jinghui chen Xingyue Xiao Xiayin yao Ningbo Institute of Materials Technology and Engineering Chinese Academy of Sciences center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences

Lithium argyrodites with high ionic conductivity and low cost are considered as one of the most prospective solid electrolytes for all-solid-state lithium ***,the poor chemical stability and compatibility with lithium metal limit their ***,Li5.4PS4.4cl1.4I0.2solid electrolyte with high ionic conductivity of 11.49 m S cm-1and improved chemical stability is synthesized by iodine *** ultra-thin Li5.4PS4.4cl1.4I0.2membrane with thickness of 10μm can be obtained by wet coating process,exhibiting a high ionic conductivity of 2.09 mS cm-1and low areal resistance of 1.17Ω***,iodine doping could in-situ form LiI at the lithium/electrolyte interface and improve the critical current density of Li5.4PS4.4cl1.6from 0.8 to 1.35 mA *** resultant LicoO2/Li5.4PS4.4cl1.4I0.2/Li battery shows excellent cycling stability at 1 c,with a reversible specific capacity of 110.1 mA h g-1and a retention of 80.5% after 1000 *** addition,the assembled LicoO2/Li5.4PS4.4cl1.4I0.2membrane/Li pouch cell delivers an initial discharge capacity of 110.4 mA h g-1and 80.5% capacity retention after 100 cycles.

关键词： Argyrodite electrolytes Iodine doping Ionic conductivity Stability All-solid-state lithium battery