检索结果-南通市图书馆

Effect of FeSi additive in dual-chamber sample cup on thermal analysis characteristic values and vermiculating rate of compacted graphite iron

在线全文

学校读者我要写书评

暂无评论

China Foundry 2024年第1期21卷 91-100页

作者： De-quan Shi Ze-yu Liu gui-li gao Yi-cheng feng School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China School of Materials Science and Chemical Engineering Harbin University of Science&TechnologyHarbin 150040China School of Mechanical and Energy Engineering Shanghai Technical Institute of Electronics and InformationShanghai 201411China

Thermal analysis plays a key role in the online inspection of molten iron *** solidification process of molten iron can be reflected by thermal analysis curves,and silicon is one of important elements affecting the solidification of molten *** this study,FeSi75 was added in one chamber of the dual-chamber sample cup,and the influences of FeSi75 additive on the characteristic values of thermal analysis curves and vermiculating rate were *** results show that with the increase of FeSi75,the start temperature of austenite formation TALfirstly decreases and then increases,but the start temperature of eutectic growth TSEF,the lowest eutectic temperature TEU,temperature at maximum eutectic reaction rate TEM,and highest eutectic temperature TERkeep always an *** temperature at final solidification point TEShas little *** FeSi75 additive has different influences on the vermiculating rate of molten iron with different vermiculation,and the vermiculating rate increases for lower vermiculation molten iron while decreases for higher *** to the thermal analysis curves obtained by a dual-chamber sample cup with 0.30wt.%FeSi75 additive in one chamber,the vermiculating rate of molten iron can be evaluated by comparing the characteristic values of these *** time differenceΔtERcorresponding to the highest eutectic temperature TERhas a closer relationship with the vermiculating rate,and a parabolic regression curve between the time differenceΔtERand vermiculating rateηhas been obtained within the range of 65%to 95%,which is suitable for the qualified melt.

关键词： FeSi75 additive characteristic value vermiculating rate thermal analysis compacted graphite iron

Uncovering Microstructure-Property Relationship in Ni-Alloyed Fe-Mn-Al-C Low-Density Steel Treated by Hot-Rolling and Air-Cooling Process

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 713-725页

作者： Xiaoliang Jia Guhui gao Xiaolu gui Chun feng R.D.K.Misra Bingzhe Bai School of Mechanical Electronicand Control EngineeringBeijing Jiaotong UniversityBeijing100044China CNPC Tubular Goods Research Institute Xi’an710077China Laboratory for Excellence in Advanced Steel Research University of Texas at El PasoEl PasoTX79968-0521USA School of Material Science and Engineering Key Laboratory of Advanced Materials of Ministry of EducationTsinghua UniversityBeijing100084China

This paper focuses on the relationship between the microstructure and tensile properties of Fe-Mn-Al-C low-density high-strength steel processes by hot-rolling and air-cooling process. The microstructure analysis reveals that the combination of hot-rolling and air-cooling results in the formation of heterogeneous structures comprising different-sized γ and B_(2) phases in the low-density steel with the addition of nickel (Ni). The addition of Ni promotes the formation of the B_(2) phase and induces the pinning of B_(2) phase particles at the γ grain boundaries. This pinning effect effectively hinders the growth of the γ grains, leading to grain refinement. The tensile test results demonstrate that LDS-5Ni (low-density steel, LDS) exhibits excellent high strength and ductility combination, e.g., a tensile strength of 1535 MPa, yield strength of 1482 MPa, and elongation of 23.3%. These remarkable mechanical properties are primarily attributed to the combined strengthening contributions of grain refinement and duplex nano-sized second-phase precipitation hardening.

关键词： Low-density steel Microstructure B_(2)phase κ-Carbide Tensile properties

A Nominative Multi-Proxy Signature Scheme Based on ECC

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

Wuhan University Journal of Natural Sciences 2005年第1期10卷 223-226页

作者： MAChuan-gui gaofeng-xiu WANGYan CollegeofInformationEngineering InformationEngineeringUniversity.Zhengzhou450002HenanChina

A nominative multi-proxy signature in which the original signer authorizes a group of proxy signers is presented. Meanwhile, our proposed scheme is based on elliptic curve cryptosystem which is more efficient than the... 详细信息

关键词： proxy signature nominative proxy signature multi-proxy signature elliptic curve cryptosystem (ECC)

Record-high efficiency perovskite LEDs achieved by accelerating radiative recombination

在线全文

学校读者我要写书评

暂无评论

Science China Materials 2024年第9期67卷 3039-3040页

作者： feng gao Department of Physics Chemistry and BiologyLinköping UniversityLinköping58183Sweden

Light-emitting diodes(LEDs)have revolutionized the lighting and displays due to their superior energy *** increasing demand for more efficient and brighter thin-film LEDs in flat-panel displays and solid-state lighting applications has driven extensive research into perovskite materials,which show great promise for high brightness and efficiency.

关键词： lighting radiative high

Molecule doping enables high-quality perovskite junctions for all-perovskite tandem solar cells

在线全文

学校读者我要写书评

暂无评论

National Science Review 2024年第7期11卷 69-70页

作者： Lingeswaran Arunagiri feng gao Department of Physics Chemistry and Biology(IFM) Link?ping University

The maximum theoretical power conversion efficiency(PCE) for single-junction solar cells based on the Shockley-Queisser(S-Q) model is 33.7% for an optimal bandgap(Eg) of 1.34 eV under 1-sun illumination [1]. Multijunction(tandem) solar cells present a realistic option for overcoming the S-Q limit and achieving efficiency of >40%due to decreased thermalization loss in tandem configuration [2].

关键词： METAL HALIDE PEROVSKITES

Love wave propagation in one-dimensional piezoelectric quasicrystal multilayered nanoplates with surface effects

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 619-632页

作者： Xin feng Liaoliang KE Yang gao College of Science China Agricultural UniversityBeijing 100083China School of Mechanical Engineering Tianjin UniversityTianjin 300350China

The exact solutions for the propagation of Love waves in one-dimensional(1D)hexagonal piezoelectric quasicrystal(PQC)nanoplates with surface effects are *** electro-elastic model is developed to investigate the anti-plane strain problem of Love wave *** introducing three shape functions,the wave equations and electric balance equations are decoupled into three uncorrelated *** the boundary conditions of the top surface on the covering layer,the interlayer interface,and the matrix,a dispersive equation with the influence of multi-physical field coupling is provided.A surface PQC model is developed to investigate the surface effects on the propagation behaviors of Love waves in quasicrystal(QC)multilayered structures with nanoscale thicknesses.A novel dispersion relation for the PQC structure is derived in an explicit closed form according to the non-classical mechanical and electric boundary *** examples are given to reveal the effects of the boundary conditions,stacking sequence,characteristic scale,and phason fluctuation characteristics on the dispersion curves of Love waves propagating in PQC nanoplates with surface effects.

关键词： piezoelectric quasicrystal(PQC)material multilayered plate dispersion characteristic surface effect

Analysis and Key Parameter Optimization Design of Leningrader Seal Performance

在线全文

学校读者我要写书评

暂无评论

Wuhan University Journal of Natural Sciences 2024年第2期29卷 177-192页

作者： YANG Dongya WANG Xuelin WANG feng ZHANG Hailong gao gui College of Mechanical and Electrical Engineering Lanzhou University of TechnologyLanzhou 730050Gansu China Wenzhou Pump and Valve Engineering Research Institute Lanzhou University of TechnologyWenzhou 325000ZhejiangChina State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000GansuChina

In order to improve the performance and service life of the Leningrader seal of the Stirling engine piston rod,interference,pre-load and friction coefficient were taken as influencing factors,and the curved surface response method was adopted to reduce the contact stress of sealing surface and von Mises stress of the sealing sleeve as the response index,with the optimization goal of reducing wear and extending *** above three key parameters are analyzed and optimized,the influence of each parameter on the sealing performance and service life is obtained,and the best combination scheme of the three is *** results show that the interaction between pre-tightening force and interference fit has the greatest impact on contact *** interaction between interference fit and friction coeffi-cient has the most significant effect on von Mises *** optimized parameters can reduce the maximum contact stress and maximum von Mises stress of the sealing sleeve by 26.3%and 20.6%,respectively,under a media pressure of 5-9 *** bench verification shows that the leakage of the optimized sealing device in 12 h is reduced by 0.44 cc·min^(-1)(1 cc=1 cm^(3)).The wear rate of the sealing sleeve is 1.08%before optimization and 0.45%after optimization,indicating that the optimized parameters in this paper are effective.

关键词： Leningrader seal Stirling engine performance analysis optimized design parameter configuration

Bayesian partial pooling to reduce uncertainty in overcoring rock stress estimation

在线全文

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1192-1201页

作者： Yu feng Ke gao Suzanne Lacasse Norwegian Geotechnical Institute OsloNorway Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhenChina

The state of in situ stress is a crucial parameter in subsurface engineering,especially for critical projects like nuclear waste *** one of the two ISRM suggested methods,the overcoring(OC)method is widely used to estimate the full stress tensors in rocks by independent regression analysis of the data from each OC ***,such customary independent analysis of individual OC tests,known as no pooling,is liable to yield unreliable test-specific stress estimates due to various uncertainty sources involved in the OC *** address this problem,a practical and no-cost solution is considered by incorporating into OC data analysis additional information implied within adjacent OC tests,which are usually available in OC measurement ***,this paper presents a Bayesian partial pooling(hierarchical)model for combined analysis of adjacent OC *** performed five case studies using OC test data made at a nuclear waste repository research site of *** results demonstrate that partial pooling of adjacent OC tests indeed allows borrowing of information across adjacent tests,and yields improved stress tensor estimates with reduced uncertainties simultaneously for all individual tests than they are independently analysed as no pooling,particularly for those unreliable no pooling stress estimates.A further model comparison shows that the partial pooling model also gives better predictive performance,and thus confirms that the information borrowed across adjacent OC tests is relevant and effective.

关键词： Overcoring stress measurement Uncertainty reduction Partial pooling Bayesian hierarchical model Nuclear waste repository

Efficient Monolithic Perovskite/Silicon Tandem Photovoltaics

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

Energy & Environmental Materials 2024年第3期7卷 268-281页

作者： Yong Wang Yu Wang feng gao Deren Yang State Key Laboratory of Silicon Materials and School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027China ZJU-Hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 310014China Department of Physics Chemistry and Biology(IFM)Linköping UniversityLinköping 58183Sweden

Tunable bandgaps make halide perovskites promising candidates for developing tandem solar cells(TSCs),a strategy to break the radiative limit of 33.7%for single-junction solar *** perovskites with market-dominant crystalline silicon(c-Si)is particularly attractive;simple estimates based on the bandgap matching indicate that the efficiency limit in such tandem device is as high as 46%.However,state-of-the-art perovskite/c-Si TSCs only achieve an efficiency of~32.5%,implying significant challenges and also rich *** this review,we start with the operating mechanism and efficiency limit of TSCs,followed by systematical discussions on wide-bandgap perovskite front cells,interface selective contacts,and electrical interconnection layer,as well as photon management for highly efficient perovskite/c-Si *** highlight the challenges in this field and provide our understanding of future research directions toward highly efficient and stable large-scale wide-bandgap perovskite front cells for the commercialization of perovskite/c-Si TSCs.

关键词： 2-terminal electrical interconnection perovskite/silicon tandem photovoltaics photon management wide-bandgap perovskites