检索结果-南通市图书馆

Influence of deformation on the corrosion behavior of LZ91 Mg-Li alloy

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2023年第1期30卷 72-81页

作者： Xueqin Liu Xuejian wang Enyu Guo Zongning Chen Huijun Kang Tongmin wang Key Laboratory of Solidification Control and Digital Preparation Technology(Liaoning Province) School of Materials Science and EngineeringDalian University of TechnologyDalian 116024China Ningbo Institute of Dalian University of Technology Ningbo 315000China

The effect of rolling and forging on the microstructure and corrosion behavior of LZ91 alloy was investigated using an electron probe micro-analyzer,immersion and electrochemical *** showed that the area fraction of theβ-Li phase remained unchanged,and the grain size of theβ-Li phase decreased after *** as-rolled forged alloy(FR-LZ91)exhibited the highest area fraction of theβ-Li phase and the longest *** corrosion resistance of the forged LZ91 alloy increased due to grain refinement that prevented further corrosion during the immersion *** the experimental alloys,FR-LZ91 showed the highest resistance of corrosion film and charge transfer resistance values due to its protective film caused by the high area fraction of theβ-Li phase.

关键词： magnesium lithium alloy deformation electrochemical test corrosion behavior

A time sequential microfluid sensor with Tesla valve channels

在线全文

学校读者我要写书评

暂无评论

Nano Research 2023年第9期16卷 11667-11673页

作者： Pengcheng Zhao Haobin wang Yaozheng wang Wei Zhao Mengdi Han Haixia Zhang National Key Laboratory of Science and Technology on Micro/Nano Fabrication Beijing Advanced Innovation Center for Integrated CircuitsSchool of Integrated CircuitsPeking UniversityBeijing 100871China Department of Cardiology and Institute of Vascular Medicine NHC Key Laboratory of Cardiovascular Molecular Biology and Regulatory PeptidesKey Laboratory of Molecular Cardiovascular ScienceMinistry of EducationBeijing Key Laboratory of Cardiovascular Receptors ResearchPeking University Third HospitalBeijing 100191China Department of Biomedical Engineering College of Future Technology Peking UniversityBeijing 100871China

The concentration of biomarkers in sweat can be used to evaluate human health,making efficient sweat sensing a focus of *** flow channel design is often used to detect sweat velocity,it is rarely incorporated into the sensing of biomarkers,limiting the richness of sensing *** this study,we report a time sequential sensing scheme for uric acid in sweat through a sequential design of Tesla valve *** electrodes for detecting uric acid and directional Tesla valve flow channels were fabricated using laser engraving technology to realize time sequential *** performance of the channels was verified through *** time sequential detection of uric acid concentration in sweat can help researchers improve the establishment of human health management systems through flexible wearable devices.

关键词： time sequential sensing uric acid Tesla valves laser engraving technology

Effect of substrate preset temperature on crystal growth and microstructure formation in laser powder deposition of single-crystal superalloy

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2018年第11期34卷 2116-2124页

作者： Zhaoyang Liu Zi wang College of Innovation and Entrepreneurship Southern University of Science and Technology Shenzhen Key Laboratory for Additive Manufacturing of High Performance Materials Southern University of Science and Technology State Key Laboratory of Powder Metallurgy Central South University

A successful repair of single-crystal components needs to avoid the stray grain formation and achieves continuous epitaxial growth of columnar dendrites in the repaired zone. In this study, the effect of substrate preset temperature on crystal growth and microstructure formation in laser powder deposition of single-crystal superalloy was studied through an improved mathematical model and corresponding experimental approaches. The results indicated that the variation of substrate preset temperature between-30℃ and ＋210℃ changes the molten pool morphology little, but obviously affects the columnar-to-equiaxed transition conditions. The preheating of substrate facilitates the stray grain formation and enlarges the primary columnar dendrite arm spacing, while the situation for precooling of substrate is opposite. Under the specific processing conditions, the critical condition for continuous epitaxial growth is that the substrate preset temperature Tsub≤ ＋90℃. When the substrate preset temperature Tsubis below ＋90℃, the height ratio of melting depth to total height of the molten pool is larger than that of stray grain, ensuring that stray grains can be completely remelted and the continuous columnar dendrites during the multi-layer laser powder deposition process on（001） surface of single-crystal substrate can be achieved.

关键词： Single-crystal superalloy Crystal growth Laser powder deposition

Modeling radiative effects of haze on summer-time convective precipitation over North China： a case study

在线全文

学校读者我要写书评

暂无评论

Frontiers of Environmental Science & Engineering 2016年第4期10卷 105-114页

作者： Xuying wang Bin ZHANG School of Environment Tsinghua University Beijing 100084 China Chinese Academy for Environmental Planning Beijing 100012 China Ministry of Education Key Laboratory for Earth System Modeling Center for Earth System Science Institute for Global Change Studies Tsinghua University Beijing 100084 China

The impact of haze radiative effect on summertime 24-h convective precipitation over North China was investigated using WRF model （version 3.3） through model sensitivity studies between scenarios with and without aerosol radiative effects. The haze radiative effect was represented by incorporating an idealized aerosol optical profile, with AOD values around 1, derived from the aircraft measurement into the WRF shortwave scheme. We found that the shortwave heating induced by aerosol radiative effects would significantly reduce heavy rainfalls, although its effect on the post-frontal localized thunderstorm precipitation was more diverse. To capture the key factors that determine whether precipitation is enhanced or suppressed, model grids with 24-h precipitation difference between the ：two scenarios exceeding certain threshold （〉30 mm or〈 -30 mm） were separated into two sets. Analyses of key meteorological variables between the enhanced and suppressed regimes suggested that atmospheric convection was the most important factor that determined whether precipitation was enhanced or suppressed during summertime over North China. The convection was stronger over places with precipitation enhancement over 30 mm. Haze weakened the convection over places with precipitation suppression exceeding 30 mm and caused less water vapor to rise to a higher level and thus further suppressed precipitation. The suppression of precipitation was often accompanied with relatively high convective available potential energy （CAPE）, relative humidity （RH） and updraft velocities.

关键词： Haze Aerosol radiative effects Convective precipitation

In situ Reduction of Silver Nanoparticles on Chitosan Hybrid Copper Phosphate Nanoflowers for Highly Efficient Plasmonic Solar-driven Interfacial Water Evaporation

在线全文

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2021年第1期18卷 30-39页

作者： Mei Zhang wanghuai Xu Minfei Li Jiaqian Li Peng wang Zuankai wang Department of Mechanical Engineering City University of Hong KongHong Kong999077China Department of Civil and Environmental Engineering the Hong Kong Polytechnic UniversityHong Kong999077China

The development of water purification device using solar energy has received tremendous *** extensive progress,traditional photothermal conversion usually has a high cost and high environmental *** overcome this problem,we develop a low cost,durable and environmentally friendly solar *** bilayered evaporator is constructed with a thermal insulating polyvinylidene fluoride(PVDF)membrane as a bottom supporting layer and plasmonic silver nanoparticles decorated miero-sized hybrid flower(Ag/MF)as a top light-to-heat conversion *** with the sample with a flat silver film,the two-tier Ag/MF has a plasmonic enrichment property and high efficiency in converting the solar light to hcat as cach flower can gencrate a microscale hotspot by enriching the absorbed solar *** the other hand,the PVDF membrane on the bottom with porous structure not only improves the mechanicalstability of the entire structure,but also maintains a stable water supply from the bulk water to the evaporation interface by capillarity and minimizes the thermal *** combination of excellent water evaporation ability simple operation,and low cost of the production process imparts this type of plasmonic enhanced solar-driven interfacial water evaporator with promising prospects for potable water purification for point-of-use applications.

关键词： bionic plasmonic water evaporation synergistic effect Ag NPs hybrid flower

Influence of travel speed on microstructure and mechanical properties of wire + arc additively manufactured 2219 aluminum alloy

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2020年第2期37卷 143-153页

作者： Yinghui Zhou Xin Lin Nan Kang Weidong Huang Jiang wang Zhennan wang State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design MIIT ChinaNorthwestern Polytechnical UniversityXi’an 710072China

Wire+arc additive manufacturing(WAAM)was preliminarily employed to fabricate the 2219 aluminum *** influence of the electric arc travel speed(TS)on the macro-morphology,microstructure,and mechanical properties were *** results indicated that as the electric arc TS increased,the size and the volume fraction of equiaxed grain *** high arc TS during WAAM also promoted the precipitation of theθ(Al2Cu)*** volume fractions ofθ’’andθ’phases reached maximum values when TS is 350 and 250 mm/min,*** thermal cycle facilitated the precipitation of theθ’*** addition,the micro-hardness and tensile strength of the alloy were analyzed,and the results indicated that samples fabricated at TS of 350 mm/min possessed finer equiaxed grain and exhibited higher ultimate tensile strength(273.5 MPa)and yield strength(182.9 MPa)compared to those fabricated at 250 mm/min.

关键词： Wire+arc additive manufacturing 2219 aluminum alloy Microstructure Mechanical properties

Thermodynamic property of ternary compound MgCaSi: A study from ab initio Debye-Grüneisen model

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2021年第12期34卷 315-322页

作者： Rui Wu Ya-Ping wang Lin Shao Wei wang Bi-Yu Tang School of Chemistry and Chemical Engineering Guangxi UniversityNanning 530004China Institute of Biological Manufacturing Technology Co.Ltd Guangxi Institute of Industrial TechnologyNanning 530022China

The thermodynamic properties of Mg Ca Si and its mother phase Ca2 Si are comparatively investigated from ab initio calculations and quasi-harmonic Debye-Grüneisen model. At 0 K, Mg Ca Si is more thermodynamically stable. Under high temperature, the advantage of higher thermodynamically stability of Mg Ca Si is reduced, originating from the less negative entropy contribution because the thermodynamic entropy of Mg Ca Si increases more slowly with temperature and the entropy values are slightly *** increasing temperature, the anti-softening ability for Mg Ca Si is slightly smaller due to the slightly faster decrease trend of bulk modulus than that of Ca2 Si, although the bulk modulus of Mg Ca Si is higher in the whole temperature range considered. The thermal expansion behaviors of both Mg Ca Si and Ca_(2)Si exhibit similar increase trend, although thermal expansion coefficient of MgCaSi is slightly lower and the increases is slightly slower at lower temperature. The isochoric heat capacity CVand isobaric heat capacity CPof MgCaSi and Ca_(2)Si rise nonlinearly with temperature, and both CVare close to the Dulong–Petit limit at high temperature due to the negligibly small electronic contribution. The Debye temperature of both phases decrease with increasing temperature, and the downtrend for Mg Ca Si is slightly ***, MgCaSi possess slightly higher Debye temperature, implying the stronger chemical bonds and higher thermal conductivity than the mother phase Ca_(2)Si. The Grüneisen parameter of MgCaSi and Ca_(2)Si increase slightly with temperature, the values of MgCaSi are slightly larger. The investigation of electronic structures shows that with substitution of partial Ca by Mg in Ca_(2)Si, the stronger MgASi,MgACa and SiASi covalent bonds are formed, and plays a very significant role for the structural stability and mechanical properties.

关键词： MgCaSi alloys Density functional theory Thermodynamic properties Structural stabilities Quasi-harmonic Debye-Grüneisen model

Recent Progress in Emerging Two‑Dimensional Transition Metal Carbides

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2021年第11期13卷 375-408页

作者： Tianchen Qin Zegao wang Yuqing wang Flemming Besenbacher Michal Otyepka Mingdong Dong College of Materials Science and Engineering Sichuan UniversityChengdu 610065People’s Republic of China Interdisciplinary Nanoscience Center Aarhus University8000 AarhusDenmark Regional Centre of Advanced Technologies and Materials Department of Physical ChemistryFaculty of SciencePalacky University77146 OlomoucCzech Republic

As a new member in two-dimensional materials family,transition metal carbides(TMCs)have many excellent properties,such as chemical stability,in-plane anisotropy,high conductivity and flexibility,and remarkable energy conversation efficiency,which predispose them for promising applications as transparent electrode,flexible electronics,broadband photodetectors and battery ***,up to now,their device applications are in the early stage,especially because their controllable synthesis is still a great *** review systematically summarized the state-of-the-art research in this rapidly developing field with particular focus on structure,property,synthesis and applicability of ***,the current challenges and future perspectives are outlined for the application of 2D TMCs.

关键词： Two-dimensional transition metal carbides Phase diagram Superconductivity Energy conversation and storage Largescale synthesis

Permeability evolution and gas flow in wet coal under non-equilibrium state:Considering both water swelling and process-based gas swelling

在线全文

学校读者我要写书评

暂无评论

International Journal of Mining Science and Technology 2023年第5期33卷 585-599页

作者： Zhiyong Xiao Gang wang Changsheng wang Yujing Jiang Feng Jiang Chengcheng Zheng Shandong Provincial Key Laboratory of Civil Engineering Disaster Prevention and Mitigation Shandong University of Science and TechnologyQingdao 266590China College of Civil Engineering Fujian University of TechnologyFuzhou 350118China c State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and TechnologyQingdao 266590China

Accurate knowledge of gas flow within the reservoir and related controlling factors will be important for enhancing the production of coal bed *** present,most studies focused on the permeability evolution of dry coal under gas adsorption equilibrium,gas flow and gas diffusion within wet coal under the generally non-equilibrium state are often ignored in the process of gas *** this study,an improved apparent permeability model is proposed which accommodates the water and gas adsorption,stress dependence,water film thickness and gas flow *** the process of modeling,the water adsorption is only affected by water content while the gas adsorption is time and water content dependent;based on poroelastic mechanics,the effective fracture aperture and effective pore radius are derived;and then the variation in water film thickness for different pore types under the effect of water content,stress and adsorption swelling are modeled;the flow regimes are considered based on Beskok’s ***,after validation with experimental data,the proposed model was applied to numerical simulations to investigate the evolution of permeability-related factors under the effect of different water *** gas flow in wet coal under the non-equilibrium state is explicitly revealed.

关键词： Gas flow Apparent permeability Water film Adsorption Non-equilibrium state