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Acta Metallurgica Sinica(English Letters) 2000年第1期13卷 254-262页

作者： J. f. Gu J. S. Pan M. J. hu and f. f. Shen (School of.Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200030, China)

Complicated changns occur inside the steel parts during quenching process. The abruptly changed boundary conditions make the temperature f.eld,micro - structure and stress f.eld change dramatically in very short time, and these variables take a contact interactions in the whole process. In this paper, a three dimensional non - linear mathematical model f.r queeching process has been f.unded and the numerical simulation on temperature f.eld,microstructre and stress f.eld has been *** the f.M analysis, the incremental iteration method is used to deal with such complicated nonlinear as boundary nonlinear, physical property nonlinear,transf.rmation nonlinear *** ef.ect of.stress on transf.rmation kinetics has been considered in the calculation of.microstructure. In the stress f.eld anal- ysis,a thermo- elasto - plastic model has been f.unded, which considers such f.ctors as transf.rma- tion strain,transf.rmation plastic strain, themal strain and the ef.ect of.temperature and transf.rma- tion on mechanical propertier etc. The transient temperature f.eld, microstructure distribution and stress f.eld of.the roller on any time can be displayed vividly,and the cooling curve and the changes of.stress on any position can also be given.

关键词： quenching,phase transf.rmation,temperature f.eld stress f.eld f.nite element method (f.M) numerical simulation

Curing Behaviors and Thermal Properties of.Dimer f.tty Acid （Df.） Modif.ed Multif.nctional Epoxy Resin

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Journal of.Donghua University(English Edition) 2013年第6期30卷 525-529页

作者： Yu M.-M. Sun J.-L. Ren M.-S. Li A.-J. Bai R.-C. hu H.-f. Research Center f.r Composite Materials Shanghai University Shanghai 200072 China Department of.Polymer Materials Shanghai University Shanghai 201800 China

In order to improve the toughness of.the cured aromatic tetraf.nctional epoxy resins, a dlmer rarboxylic acid named dlmer f.tty acid （Df.） was used to modif. an aromatic tetraf.nctional epoxy, N, N, N＇, N＇-tetraglycidyl-2,2-bis [ 4-（ 4-aminophcuoxy ） phenyl ] propane （TGBAPP）. The curing behaviors of.Df.- TGBAPP/MNA （ methyl nadic anhydride） systems were studied by dif.erential scanning calorimetry （DSC） method. And the thermal properties of.the cured epoxy resin were investigated with the thermo-gravimetric analysis （TGA） and dynamic mechanical analysis （DMA）. Besides, the toughness was characterized with the impact strength tested by charpy impact testing. The results indicated that the modif.cation would improve the curing reactions, and the curing temperatures were decreased with the increasing content of.Df.. The thermal properties were not inf.uenced obviously, and the toughness could be improved when the epoxy resin was modif.ed with Df..

关键词： curing behavior thermal property N, N, N', N'- telraglycidyl-2, 2-bis [ 4-( 4-aminophenoxy ) phenyl ] propane (TGBAPP) dimer f.tty acid ( Df.) toughen

用于拟合生产动态数据的现有储层模型重构(英文)

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地学前缘 2008年第1期15卷 176-186页

作者： M. Le Ravalec-Dupin L. Y. hu f. Roggero Reservoir Engineering Division IFP 1 ＆ 4 Avenue de Bois Preau 92852 Rueil-Malmaison Cedex France

计算机能力的提升和历史拟合方面的最新进展促进了对先前建立的储层模型的重新检验。为了节省工程师和CPU的时间,我们开发了4种独特的算法,来允许无需重新进行储层研究而重建现有模型。这些算法涉及的技术包括:优化、松弛、Wiener滤波... 详细信息

计算机能力的提升和历史拟合方面的最新进展促进了对先前建立的储层模型的重新检验。为了节省工程师和CPU的时间,我们开发了4种独特的算法,来允许无需重新进行储层研究而重建现有模型。这些算法涉及的技术包括:优化、松弛、Wiener滤波或序贯重构。基本上,它们被用来确定一个随机函数和一系列随机数。给定一个随机函数,一族随机数将产生一个实现,这个实现和现有的储层模型十分接近。一旦随机数已知,现有的储层模型将被提交到一个历史拟合过程中,以此来改进数据拟合度或者考虑新收集到的数据。我们关注的是先前建立的相储层模型。虽然我们对模型模拟的方式一无所知,但是我们可以确定一系列随机数,再用多点统计模拟方法来建造一个和现有储层模型十分接近的实现。然后运行一种新的历史拟合程序来更新现有的储层模型,使其拟合两口新生产井的流量数据。

关键词：储层非均质地质统计学模拟最优化历史拟合

Ef.icient concentration of.trace analyte with ordered hotspot construction f.r a robust and sensitive SERS platf.rm

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International Journal of.Extreme Manuf.cturing 2024年第3期6卷 532-542页

作者： Youdi hu Yanlei hu Zhenyu Wang Jiale Yong Wei Xiong Dong Wu Shixiang Xu Shenzhen Key Laboratory of.Micro-Nano Photonic Inf.rmation Technology College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhenGuangdong 518060People’s Republic of China CAS Key Laboratory of.Mechanical Behavior and Design of.Materials Key Laboratory of Precision Scientific Instrumentation of Anhui Higher Education InstitutesDepartment of Precision Machinery and Precision InstrumentationUniversity of Science and Technology of ChinaHefeiAnhui 230027People’s Republic of China Wuhan National Laboratory f.r Optoelectronics Huazhong University of Science and TechnologyWuhanHubeiPeople’s Republic of China

Surf.ce-enhanced Raman scattering(SERS)platf.rm,which enables trace analyte detection,has important application *** structuring/modif.ing the surf.ce of.the SERSsubstrate,analyte in highly diluted solutions can be concentrated into localized active areas f.r highly sensitive ***,subject to the dif.iculty of.the f.brication process,itremains challenging to balance hot-spot construction and the concentration capacity of.analyte ***,preparing SERS substrates with densely ordered hot spots andef.icient concentration capacity is of.great signif.cance f.r highly sensitive ***,we propose an Ag and f.uoroalkyl-modif.ed hierarchical armour substrate(Ag/f.HA),which has a double-layer stacking design to combine analyte concentration with hotspot *** microarmour structure is f.bricated by f.mtosecond-laser processing to serve as asuperhydrophobic and low-adhesive surf.ce to concentrate analyte,while the anodic aluminium oxide(AAO)template creates a nanopillar array serving as dense and ordered hot *** the synergistic action of.hot spots and analyte concentration,Ag/f.HA achieves a detectionlimit down to 10^(-7)M doxorubicin(DOX)molecules with a RSD of.7.69%.Additionally,Ag/f.HA exhibits excellent robustness to resist external disturbances such as liquid splash or *** on our strategy,SERS substrates with directional analyte concentrations are f.rther explored by patterning microcone arrays with *** work opens a way to the realistic implementation of.SERS in diverse scenarios.

关键词： surf.ce-enhanced Raman scattering anodic aluminium oxide f.mtosecond laser processing concentration of.trace analytes mechanical robustness

Tensor perturbations f.om bounce inf.ation scenario in f.Q)gravity

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 78-92页

作者： Kun hu Tanmoy Paul Taotao Qiu Institute of.Astrophysics Central China Normal UniversityWuhan 430079China School of.Physics Huazhong University of Science and TechnologyWuhan 430074China National Institute of.Technology Jamshedpur Department of PhysicsJamshedpur 831014India

In this paper,we construct a bounce inf.ation cosmological scenario in the f.amework of.the modif.ed symmetric teleparallel gravity,namely f.Q)theory,and investigate the tensor perturbations *** is well-known,the tensor perturbations generated in the very early Universe(inf.ation and pre-inf.ation regions)can account f.r the primordial gravitational waves(PGWs)that are to be detected by the next generation of.GW *** discuss the stability condition of.the tensor perturbations in the bounce inf.ation process and investigate in detail the evolution of.the perturbation *** general f.rm of.the tensor power spectrum is obtained both f.r large as well as small scale *** a result,we show both kinds of.modes(short or long wavelength modes),and the tensor spectrum may get a positive tilt in the parametric range where the tensor perturbation proves to be stable—this interestingly hints an enhancement of.gravitational waves’amplitude in the background of.the f.Q)bounce-inf.ation ***,we study the LQC-like scenario as a specif.c case of.our model,in which,the primordial tensor power spectrum turns out to be nearly scale-invariant on both small and large scales.

关键词： bounce cosmology modif.ed gravity cosmological perturbations

The electronic properties of.carbon nanotubes with def.cts

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The electronic properties of carbon nanotubes with defects

A f.cile Li_(2)TiO_(3) Surf.ce Modif.cation to Improve the Structure Stability and Electrochemical Perf.rmance of.f.ll Concentration Gradient Li-Rich Oxides

2005年全国计算材料、模拟与图像分析学术会议

作者： H.f.hu, L. f. Zhang Department of.Applied Physics, hunan University, Changsha 410082, China Department of.f.ndamental Courses, Tianjin University of.commerce, Tianjin 300134, China

Using the extensional Su-Schrif.er-Heeger (SSH) model in real space, we study the electronic properties of.single-walled carbon nanotubes with pentagon-heptagon pair (5/7) def.cts in the hexagonal network of.the zigzag conf.guration. The calculated results show that the pentagon-heptagon pair def.cts on the nanotube structure are not only responsible f.r a change in nanotube diameter, but also govern the electronic behavior around f.rmi level. There exist some localized states in the vicinity of.the f.rmi energy, and the symmetry of.the curve of.density of.electronic states is broken remarkably in these systems. f.nally, we explore the ef.ects of.pentagon-heptagon pair def.cts on the electronic properties of.the systems.

关键词： Carbon nanotube, topological def.cts, Su-Schrif.er-Heeger model

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Energy & Environmental Materials 2024年第3期7卷 41-48页

作者： Naif.ng hu Yuan Yang Lin Li Yuhan Zhang Zhiwei hu Lan Zhang Jun Ma Guanglei Cui Qingdao Industrial Energy Storage Research Institute Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdao 266101China Institute of.Materials Science and Engineering Ocean University of ChinaQingdao 266100China School of.f.ture Technology University of Chinese Academy of SciencesBeijing 100049China Max Planck Institute f.r Chemical Physics of.Solids Nothnitzer Strasse 40Dresden D-01187Germany CAS Key Laboratory of.Green Process and Engineering Beijing Key Laboratory of Ionic Liquids Clean ProcessState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China Shandong Energy Institute Qingdao 266101China

f.ll concentration gradient lithium-rich layered oxides are catching lots of.interest as the next generation cathode f.r lithium-ion batteries due to their high discharge voltage,reduced voltage decay and enhanced rate perf.rmance,whereas the high lithium residues on its surf.ce impairs the structure stability and long-term cycle ***,a f.cile multif.nctional surf.ce modif.cation method is implemented to eliminate surf.ce lithium residues of.f.ll concentration gradient lithium-rich layered oxides by a wet chemistry reaction with tetrabutyl titanate and the post-annealing *** realizes not only a stable Li_(2)TiO_(3)coating layer with 3D dif.usion channels f.r f.st Li^(+)ions transf.r,but also dopes partial Ti^(4+)ions into the sub-surf.ce region of.f.ll concentration gradient lithium-rich layered oxides to f.rther strengthen its crystal ***,the modif.ed f.ll concentration gradient lithium-rich layered oxides exhibit improved structure stability,elevated thermal stability with decomposition temperature f.om 289.57℃to 321.72℃,and enhanced cycle perf.rmance(205.1 mAh g^(-1)af.er 150 cycles)with slowed voltage drop(1.67 mV per cycle).This work proposes a f.cile and integrated modif.cation method to enhance the comprehensive perf.rmance of.f.ll concentration gradient lithium-rich layered oxides,which can f.cilitate its practical application f.r developing higher energy density lithium-ion batteries.

关键词： f.ll concentration gradient lithium-rich layered oxides structure stability surf.ce modif.cation

Land use ef.ects on the dynamics of.soil C,N and microbes in the water-wind erosion crisscross region of.the northern Loess Plateau,China

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Pedosphere 2024年第1期34卷 181-190页

作者： Yi WANG Chunyue LI Shunjin hu State Key Laboratory of.Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China State Key Laboratory of.Soil Erosion and Dryland f.rming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYangling 712100China School of.Geography and Tourism Shaanxi Normal UniversityXi'an 710119China Department of.Entomology&Plant Pathology North Carolina State UniversityRaleigh 27695USA

The water-wind erosion crisscross region of.the northern Loess Plateau in China is under constant pressure f.om severe erosion due to its windy and dry climate and intensive human activities. Identif.ing sustainable land use patterns is key to maintaining ecosystem sustainability in the area. Our aim was to appraise the impacts of.dif.erent land use regimes on the dynamics of.soil total organic C(TOC), total N(TN), and microbes in a typical watershed in the northern Loess Plateau to identif. suitable land use types that can maintain soil f.rtility and sustainability. A f.eld experiment was perf.rmed in Liudaogou watershed in Shenmu City, Shaanxi Province, China, where the dynamics of.soil TOC and TN, microbial biomass C and N, microbial respiration, and net N mineralization in six typical land use types, dam land, rainf.d slope land, deciduous broadleaf.f.rest, evergreen conif.rous f.rest, shrubland, and grassland,were measured in three dif.erent growing seasons. Land use type and season signif.cantly af.ected TOC, TN, and the dynamics of.microbial biomass and activity. As the most anthropogenically disturbed land use pattern, dam land was an optimal land use pattern f.r TOC sequestration due to its higher TOC and TN, but lower microbial activity. Soil TOC, TN, and microbial properties demonstrated a decreasing trend af.er natural grassland was converted to shrubland,f.rest, and rainf.d slope land. Shrubland with exotic N-f.xing Korshinsk peashrub(Caragana korshinskii Kom.) can maintain TOC, TN, and microbial properties similar to those in grassland. Soil TOC, NH_(4+)^(-)N, TN, moisture, and extractable C were the principal indexes f.r soil microbial biomass and activity and explained 88.90% of.the total variance. Thus, grassland was the optimal land use pattern in the water-wind erosion crisscross region of.the northern Loess Plateau to maintain ecosystem stability and sustainability.

关键词： grassland microbial activity microbial biomass total organic C total N watershed

Enhancing Relational Triple Extraction in Specif.c Domains:Semantic Enhancement and Synergy of.Large Language Models and Small Pre-Trained Language Models

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Computers, Materials & Continua 2024年第5期79卷 2481-2503页

作者： Jiakai Li Jianpeng hu Geng Zhang School of.Electronic and Electrical Engineering Shanghai University of Engineering ScienceShanghai201620China

In the process of.constructing domain-specif.c knowledge graphs,the task of.relational triple extraction plays a critical role in transf.rming unstructured text into structured *** relational triple extraction models f.cemultiple challenges when processing domain-specif.c data,including insuf.icient utilization of.semantic interaction inf.rmation between entities and relations,dif.iculties in handling challenging samples,and the scarcity of.domain-specif.c *** address these issues,our study introduces three innovative components:Relation semantic enhancement,data augmentation,and a voting strategy,all designed to signif.cantly improve the model’s perf.rmance in tackling domain-specif.c relational triple extraction *** f.rst propose an innovative attention interaction *** method signif.cantly enhances the semantic interaction capabilities between entities and relations by integrating semantic inf.rmation f.omrelation ***,we propose a voting strategy that ef.ectively combines the strengths of.large languagemodels(LLMs)and f.ne-tuned small pre-trained language models(SLMs)to reevaluate challenging samples,thereby improving the model’s adaptability in specif.c ***,we explore the use of.LLMs f.r data augmentation,aiming to generate domain-specif.c datasets to alleviate the scarcity of.domain *** conducted on three domain-specif.c datasets demonstrate that our model outperf.rms existing comparative models in several aspects,with f. scores exceeding the State of.the Art models by 2%,1.6%,and 0.6%,respectively,validating the ef.ectiveness and generalizability of.our approach.

关键词： Relational triple extraction semantic interaction large language models data augmentation specif.c domains

Advanced modeling of.the absorption enhancement of.black carbon particles in chamber experiments by considering the morphology and coating thickness

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f.ontiers of.Environmental Science & Engineering 2024年第9期18卷 129-142页

作者： Xiaodong Wei Jianlin hu Chao Liu Xiaodong Xie Junjie Yin Song Guo Min hu Jianf.i Peng huijun Wang Jiangsu Key Laboratory of.Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science&TechnologyNanjing 210044China Collaborative Innovation Center on f.recast and Evaluation of.Meteorological Disasters Key Laboratory of Meteorological Disaster(Ministry of Education)Nanjing University of Information Science and TechnologyNanjing 210044China Nansen−Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China East China Air Traf.ic Management Bureau CAAC Shanghai 200335China State Key Joint Laboratory of.Environmental Simulation and Pollution Control International Joint Laboratory for Regional Pollution Control(IJRC)(Ministry of Education)College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China Tianjin Key Laboratory of.Urban Transport Emission Research&State Environmental Protection Key Laboratory of.Urban Ambient Air Particulate Matter Pollution Prevention and Control College of Environmental Science and EngineeringNankai UniversityTianjin 300071China

Measurements studies have shown that the absorption of.radiation by black carbon(BC)increases as the particles ***,there are signif.cant discrepancies between the measured and modeled absorption enhancement(E_(abs)),largely due to the simplif.cations used in modeling the mixing states and shape *** took advantage of.chamber experiments on BC aging and developed an ef.icient method to resolve the particle shape based on the relationship between the coating f.action(ΔD_(ve)/D_(ve),0)and f.actal dimension(D_(f.),which can also ref.ect the variations of.D_(f.during the whole BC aging *** with externally and partly mixed states(0≤ΔD_(ve)/D_(ve),0≤0.5)can be considered to be unif.rmly distributed with the D_(f.values of.1.8–2.1,whereas the Df.values are constrained in the range 2.2–2.8 f.r f.lly mixed states(ΔD_(ve)/D_(ve),0>0.5).The morphological parameters(i.e.,the ef.ective density and the dynamic shape f.ctor)were compared with the measured values to verif. the simulated *** simulated mean deviations of.morphological parameters were smaller than 8%f.r the method resolving the particle *** applying a realistic shape and ref.active index,the mass absorption cross f.r f.lly mixed states can be improved by 11%compared with a simplif.ed core–shell *** on our understanding of.the inf.uence of.D_(f.andΔD_(ve)/D_(ve),0 on E_(abs),we propose a two-stage calibration equation to correct the E_(abs)values estimated by the core–shell model,which reduces the simulation error in the Mie calculation by 6%–14%.

关键词： Black carbon Mixing states f.actal dimension Dynamic shape f.ctor Absorption enhancement