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Direct numerical simulations of high-pressure impinging-jet atomization:Interfacial evolutions and spray characteristics 认领 引用
1
作者 Bo WANG Erjun WU +4 位作者 Anlong YANG Feng ZHANG Baoe YANG Qingquan LIU Xiaodong CHEN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2026年第3期158-174,共17页
This study presents a numerical investigation of impinging-jet atomization across various Weber numbers(We) under high backpressure conditions.Using the volume-of-fluid method,adaptive mesh refinement,and the iso Adve... This study presents a numerical investigation of impinging-jet atomization across various Weber numbers(We) under high backpressure conditions.Using the volume-of-fluid method,adaptive mesh refinement,and the iso Advector interface reconstruction technique,atomization characteristics are simulated and analyzed for different values of We.The results indicate that the geometry induces turbulent jets,which drive turbulent atomization through the shear interactions at the gas–liquid interface.The key observed phenomena include the interaction of impact waves with liquid sheet perforation and the breakup of web of ligaments,both of which are prominent under high backpressure conditions.A novel method,based on the threshold velocity of spray droplet groups,is employed to quantitatively measure the spreading angle,showing that the angle increases with We in both front and side views.Additionally,the Sauter mean diameter of droplets follows power-law scaling with exponents of-1/3 in the upstream region and-1/2 in the downstream region,while the droplet size distribution conforms to a log-normal profile.This research provides valuable insights into interface evolution and droplet characteristics during impingingjet atomization under high backpressure,offering essential guidance for optimizing industrial atomization processes. 展开更多
关键词 Direct numerical simulations High-pressure Impinging-jet atomization Interfacial evolutions Spray characteristics
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Effect of melting temperature on microstructural evolutions, behavior and corrosion morphology of Hadfield austenitic manganese steel in the casting process 认领 引用 被引量：8
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作者 Masoud Sabzi Sadegh Moeini Far Saeid Mersagh Dezfuli 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2018年第12期1431-1438,共8页
In this study, the effect of melting temperature on the microstructural evolutions, behavior, and corrosion morphology of Hadfield steel in the casting process is investigated. The mold was prepared by the sodium sili... In this study, the effect of melting temperature on the microstructural evolutions, behavior, and corrosion morphology of Hadfield steel in the casting process is investigated. The mold was prepared by the sodium silicate/CO_2 method, using a blind riser, and then the desired molten steel was obtained using a coreless induction furnace. The casting was performed at melting temperatures of 1350, 1400, 1450, and 1500°C, and the cast blocks were immediately quenched in water. Optical microscopy was used to analyze the microstructure, and scanning electron microscopy(SEM) and X-ray diffractrometry(XRD) were used to analyze the corrosion morphology and phase formation in the microstructure, respectively. The corrosion behavior of the samples was analyzed using a potentiodynamic polarization test and electrochemical impedance spectroscopy(EIS) in 3.5 wt% NaCl. The optical microscopy observations and XRD patterns show that the increase in melting temperature led to a decrease of carbides and an increase in the austenite grain size in the Hadfield steel microstructure. The corrosion tests results show that with increasing melting temperature in the casting process, Hadfield steel shows a higher corrosion resistance. The SEM images of the corrosion morphologies show that the reduction of melting temperature in the Hadfield steel casting process induced micro-galvanic corrosion conditions. 展开更多
关键词 Hadfield steel casting process melting temperature microstructural evolutions corrosion behavior corrosion morphology
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Evolutions of sedimentary facies and palaeoenvironment and their controls on the development of source rocks in continental margin basins:A case study from the Qiongdongnan Basin,South China Sea 认领 引用 被引量：5
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作者 Kun Liu Peng Cheng +2 位作者 Cai-Wei Fan Peng Song Qiang-Tai Huang 《Petroleum Science》 SCIE EI CAS CSCD 2023年第5期2648-2663,共16页
Hydrocarbon resources in the Qiongdongnan Basin have become an important exploration target in China.However,the development of high-quality source rocks in this basin,especially in its deep-water areas,are still not ... Hydrocarbon resources in the Qiongdongnan Basin have become an important exploration target in China.However,the development of high-quality source rocks in this basin,especially in its deep-water areas,are still not fully understood.In this study,evolutions of sedimentary facies and palaeoenvironment and their influences on the development of source rocks in diverse tectonic regions of the Qiongdongnan Basin were investigated.The results show that during the Oligocene and to Miocene periods,the sedimentary environment of this basin progressively varied from a semi-closed gulf to an open marine environment,which resulted in significant differences in palaeoenvironmental conditions of the water column for various tectonic regions of the basin.In shallow-water areas,the palaeoproductivity and reducibility successively decrease,and the hydrodynamic intensity gradually increases for the water columns of the Yacheng,Lingshui,and Sanya-Meishan strata.In deep-water areas,the water column of the Yacheng and Lingshui strata has a higher palaeoproductivity and a weaker hydrodynamic intensity than that of the Sanya-Meishan strata,while the reducibility gradually increases for the water columns of the Yacheng,Lingshui,and Sanya-Meishan strata.In general,the palaeoenvironmental conditions of the water column are the most favorable to the development of the Yacheng organic-rich source rocks.Meanwhile,the Miocene marine source rocks in the deep-water areas of the Qiongdongnan Basin may also have a certain hydrocarbon potential.The differences in the development models of source rocks in various tectonic regions of continental margin basins should be fully evaluated in the exploration and development of hydrocarbons. 展开更多
关键词 Sedimentary facies Palaeoenvironmental conditions Evolutions Source rocks The Qiongdongnan basin South China Sea
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Structures and Evolutions of Explosive Cyclones over the Northwestern and Northeastern Pacific 认领 引用 被引量：4
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作者 ZHANG Shuqin FU Gang 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第3期581-593,共13页
In this study, the structures and evolutions of moderate(MO) explosive cyclones(ECs) over the Northwestern Pacific(NWP) and Northeastern Pacific(NEP) are investigated and compared using composite analysis with cyclone... In this study, the structures and evolutions of moderate(MO) explosive cyclones(ECs) over the Northwestern Pacific(NWP) and Northeastern Pacific(NEP) are investigated and compared using composite analysis with cyclone-relative coordinates. Final Operational Global Analysis data gathered during the cold seasons(October–April) of the 15 years from 2000 to 2015 are used. The results indicate that MO NWP ECs have strong baroclinicity and abundant latent heat release at low levels and strong upper-level forcing, which favors explosive cyclogenesis. The rapid development of MO NEP ECs results from their interaction with a northern cyclone and a large middle-level advection of cyclonic vorticity. The structural differences between MO NWP ECs and MO NEP ECs are significant. This results from their specific large-scale atmospheric and oceanic environments. MO NWP ECs usually develop rapidly in the east and southeast of the Japan Islands; the intrusion of cold dry air from the East Asian continent leads to strong baroclinicity, and the Kuroshio/Kuroshio Extension provides abundant latent heat release at low levels. The East Asian subtropical westerly jet stream supplies strong upper-level forcing. While MO NEP ECs mainly occur over the NEP, the low-level baroclinicity, upper-level jet stream, and warm ocean currents are relatively weaker. The merged cyclone associated with a strong middle-level trough transports large cyclonic vorticity to MO NEP ECs, which favors their rapid development. 展开更多
关键词 northern Pacific explosive cyclones composite analysis structures evolutions
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Computer Simulating Calculation on the Microstructure Evolutions during Hot Strip Rolling of C-Mn Steels 认领 引用
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作者 Zhenyu LIU Guodong WANG and Qiaing ZHANG 《Journal of Materials Science & Technology》 SCIE EI CAS 1994年第3期221-224,共4页
The program to predict the microstructure evolutions during hot strip rolling of C-M n steels has been developed in this paper, BV using this program, the microstructure changes with the processing parameters were ana... The program to predict the microstructure evolutions during hot strip rolling of C-M n steels has been developed in this paper, BV using this program, the microstructure changes with the processing parameters were analysed in detail. showing not only a good agreement of prediction with the measured values, but also entirely possibility to optimize hot strip rolling precess by computer simulation 展开更多
关键词 Mn Computer Simulating Calculation on the Microstructure Evolutions during Hot Strip Rolling of C-Mn Steels Figure
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Evaporation Characteristics and Morphological Evolutions of Fuel Droplets After Hitting Different Wettability Surfaces 认领 引用 被引量：3
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作者 Yanling Chen Liang Guo +5 位作者 Ningning Cai Wanchen Sun Yuying Yan Degang Li Han Wang Rong Xuan 《Journal of Bionic Engineering》 SCIE EI CSCD 2023年第2期734-747,共14页
To solve the wall-wetting problem in internal combustion engines,the physical and chemical etching methods are used to prepare different wettability surfaces with various microstructures.The evaporation characteristic... To solve the wall-wetting problem in internal combustion engines,the physical and chemical etching methods are used to prepare different wettability surfaces with various microstructures.The evaporation characteristics and morphological evolution processes of diesel and n-butanol droplets after hitting the various surfaces are investigated.The results show that the surface microstructures increase the surface roughness(Ra),enhancing the oleophilic property of the oleophilic surfaces.Compared with n-butanol droplets,the same surface shows stronger oleophobicity to diesel droplets.When a droplet hits an oleophilic property surface with a lower temperature,the stronger the oleophilicity,the shorter the evaporation time.For oleophilic surfaces,larger Ra leads to a higher Leidenfrost temperature(TLeid).The low TLeid caused by enhanced oleophobicity,dense microstructures and increased convex dome height facilitates droplet rebound and promotes the evaporation of the wall-impinging droplets into the cylinder.The evaporation rate of the droplets is not only related to the characteristics of the solid surfaces and the fuel droplets but also affected by the heat transfer rate to the droplets in different boiling regimes.The spreading diameter of a droplet on an oleophobic surface varies significantly less with time than that on an oleophilic surface under the same surface temperature. 展开更多
关键词 Fuel droplets Wettability Evaporation time Leidenfrost temperature Morphological evolutions
Co evolutions for WC-Co with different Co contents during pretreatment and HFCVD diamond film growth processes 认领 引用 被引量：10
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作者 Xin-chang WANG Cheng-chuan WANG +1 位作者 Wei-kai HE Fang-hong SUN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第3期469-486,共18页
Systematical researches were accomplished on WC-Co with different Co contents(6%,10%and 12%,mass fraction).Based on the XPS and EDX,from orthogonal pretreatment experiments,it is indicated that the acid concentration,... Systematical researches were accomplished on WC-Co with different Co contents(6%,10%and 12%,mass fraction).Based on the XPS and EDX,from orthogonal pretreatment experiments,it is indicated that the acid concentration,the time of the acid pretreatment and the original Co content have significant influences on the Co-removal depth(D).Moreover,the specimen temperature,original Co content and Co-removal depth dependences of the Co evolution in nucleation,heating(in pure H2 atmosphere)and growth experiments were discussed,and mechanisms of Co evolutions were summarized,providing sufficient theoretical bases for the deposition of high-quality diamond films on WC-Co substrates,especially Co-rich WC-Co substrates.It is proven that the Co-rich substrate often presents rapid Co diffusion.The high substrate temperature can promote the Co diffusion in the pretreated substrate,while acts as a Co-etching process for the untreated substrates.It is finally found that the appropriate Co-removal depth for the WC-12%Co substrate is 8-9μm. 展开更多
关键词 HFCVD diamond film WC-Co Murakami-acid pretreatment Co content Co evolution
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Cross-sectional structure, microstructure and mechanical property evolutions of brass cladding pure copper stranded wire composite during drawing 认领 引用 被引量：10
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作者 Yan-bin JIANG Yong-shuai LI +1 位作者 Yu LEI Jian-xin XIE 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第7期1857-1872,共16页
A solid/liquid continuous casting and composite technology was used to produce d8.5 mm brass cladding pure copper stranded wire composite billet and the composite billet was then drawn. The results showed that the com... A solid/liquid continuous casting and composite technology was used to produce d8.5 mm brass cladding pure copper stranded wire composite billet and the composite billet was then drawn. The results showed that the composite billet had good surface quality, metallurgical bonding interface between brass and pure copper as well as elongation of 53.1%. Synergistic deformation degree between pure copper wire and brass cladding layer was high during drawing. With an increase of the total deformation amount, the plastic deformation of the pure copper wire reduced triangular arc gaps between the pure copper wires and the triangular arc gaps were fully filled at 50%. When the total deformation amount was increased to 63%, dislocation cells and microbands successively formed in the pure copper wire. In the brass cladding layer, planar dislocation networks, twins and shear bands formed successively, and the main deformation mechanisms were dislocation sliding, twinning and shear deformation. The tensile strength increased from 240 MPa of the composite billet to 519 MPa of the one with the deformation amount of 63%, but the elongation decreased from 53.1% to 3.2%. A process of solid/liquid continuous casting and composite forming→drawing can work as a new compact method to produce brass cladding pure copper stranded wire composite as railway through grounding wire. 展开更多
关键词 solid/liquid continuous casting composite wire deformation microstructure evolution mechanical properties
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Eigen microstates and their evolutions in complex systems 认领 引用 被引量：8
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作者 Yu Sun Gaoke Hu +6 位作者 Yongwen Zhang Bo Lu Zhenghui Lu Jingfang Fan Xiaoteng Li Qimin Deng Xiaosong Chen 《Communications in Theoretical Physics》 SCIE CAS CSCD 2021年第6期140-157,共18页
Emergence refers to the existence or formation of collective behaviors in complex systems.Here,we develop a theoretical framework based on the eigen microstate theory to analyze the emerging phenomena and dynamic evol... Emergence refers to the existence or formation of collective behaviors in complex systems.Here,we develop a theoretical framework based on the eigen microstate theory to analyze the emerging phenomena and dynamic evolution of complex system.In this framework,the statistical ensemble composed of M microstates of a complex system with N agents is defined by the normalized N×M matrix A,whose columns represent microstates and order of row is consist with the time.The ensemble matrix A can be decomposed as■,where r=min(N,M),eigenvalueσIbehaves as the probability amplitude of the eigen microstate U_I so that■and U_I evolves following V_I.In a disorder complex system,there is no dominant eigenvalue and eigen microstate.When a probability amplitudeσIbecomes finite in the thermodynamic limit,there is a condensation of the eigen microstate UIin analogy to the Bose–Einstein condensation of Bose gases.This indicates the emergence of U_I and a phase transition in complex system.Our framework has been applied successfully to equilibrium threedimensional Ising model,climate system and stock markets.We anticipate that our eigen microstate method can be used to study non-equilibrium complex systems with unknown orderparameters,such as phase transitions of collective motion and tipping points in climate systems and ecosystems. 展开更多
关键词 complex system phase transition critical phenomena Earth system statistical ensemble eigen microstate dynamic evolution econophysics
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Microstructural Evolutions of AA7055 Aluminum Alloy Under Dynamic and Quasi-static Compressions 认领 引用 被引量：6
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作者 Yuanyuan Xiong Ning Li +3 位作者 Huawen Jiang Zhigang Li Zhu Xu Lin Liu 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2014年第2期272-278,共7页
The microstructural evolution of AA7055 aluminum alloy under dynamic impact loading with the strain rate of 1.3 × 10^4 s^-1 controlled by a split Hopkinson pressure bar was investigated, and compared with that un... The microstructural evolution of AA7055 aluminum alloy under dynamic impact loading with the strain rate of 1.3 × 10^4 s^-1 controlled by a split Hopkinson pressure bar was investigated, and compared with that under quasi-static mechanical loading in compression with strain rate of 1.0 × 10^-3 s^-1. The quasi-static-compressed sample exhibited equiaxed dislocation cells, which were different from the elongated and incomplete dislocation cells for the alloy undergoing dynamic compression. The high strain-rate compression also induced the formation of localized shear bands in which the recrystallizations characterized as fine equiaxed grains were observed. The microstructural evolutions under both quasi-static and dynamic compressions are rationalized in terms of the dislocation cell model combined with the dislocation kinetics, in addition to the adiabatic temperature rise in shear bands at high strain rate. 展开更多
关键词 Aluminum alloy Microstructural evolution Dynamic impact loading Dislocation cell Recrystallization
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Spectrum evolutions of spontaneous and pump-depleted stimulated Brillouin scatterings in liquid media 认领 引用 被引量：4
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作者 高玮 吕志伟 +2 位作者 何伟明 哈斯乌力吉 张赞 《Chinese Physics B》 SCIE EI CAS 2008年第10期3765-3770,共6页
A theoretical model for calculating spontaneous and stimulated Brillouin scattering（SBS） spectra is described. An empirical formula for the Stokes output spectral linewidth, a function of spontaneous Brillouin linew... A theoretical model for calculating spontaneous and stimulated Brillouin scattering（SBS） spectra is described. An empirical formula for the Stokes output spectral linewidth, a function of spontaneous Brillouin linewidth and the exponential gain coefficient, is obtained by the calculated data fitting. The formula holds true for two cases involving pump undepletion and depletion. The lineshape change from spontaneous to highly pump-depleted SBS spectra is also investigated. The result shows that for the pump power below the SBS threshold, the Stokes output spectral lincshape evolves from Lorentzian to approximately Gaussian as the pump power increases. For the pump power near or beyond the threshold, the SBS spectrum is in the form of a steady Gaussian profile, and the spectral linewidth comes to a certain value about 7 times narrower than the spontaneous one. The theoretical results are experimentally demonstrated by using several common liquid media. 展开更多
关键词 Brillouin scattering spectrum evolution linewidth lineshape
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Mechanical properties and energy evolutions of burst-prone coal samples with holes and fillings 认领 引用 被引量：3
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作者 Yukai Fu Yongzheng Wu +3 位作者 Junchen Li Penghe Zhou Zhuoyue Sun Jie He 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第3期176-189,共14页
During the mining process of impact-prone coal seams,drilling pressure relief can reduce the impact propensity of the coal seam,but it also reduces the integrity and strength of the coal mass at the side of the roadwa... During the mining process of impact-prone coal seams,drilling pressure relief can reduce the impact propensity of the coal seam,but it also reduces the integrity and strength of the coal mass at the side of the roadway.Therefore,studying the mechanical properties and energy evolution rules of coal samples containing holes and filled structures has certain practical significance for achieving coordinated control of coal mine rockburst disasters and the stability of roadway surrounding rocks.To achieve this aim,seven types of burst-prone coal samples were prepared and subject to uniaxial compression experiments with the aid of a TAW-3000 electro-hydraulic servo testing machine.Besides,the stress–strain curves,acoustic emission signals,DIC strain fields and other data were collected during the experiments.Furthermore,the failure modes and energy evolutions of samples with varying drilled hole sizes and filling materials were analyzed.The results show that the indexes related to burst propensity of the drilled coal samples decline to some extent compared with those of the intact one,and the decline is positively corelated to the diameter of the drilled hole.After hole filling,the strain concentration degree around the drilled hole is lowered to a certain degree,and polyurethane filling has a more remarkable effect than cement filling.Meanwhile,hole filling can enhance the strength and deformation resistance of coal.Hole drilling can accelerate the release of accumulated elastic strain energy,turning the acoustic emission events from low-frequency and high-energy ones to high-frequency and low-energy ones,whereas hole filling can reduce the intensity of energy release.The experimental results and theoretical derivation demonstrate that hole filling promotes coal deformability and strength mainly by weakening stress concentration surrounding the drilled holes.Moreover,the fillings can achieve a better filling effect if their elastic modulus and Poisson’s ratio are closer to those of the coal body. 展开更多
关键词 Rock mechanics Coal Mechanical properties Hole filling Energy evolution
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Evolutions of Microstructure and Mechanical Properties in Mg-5Li-1Zn-0.5Ag-0.5Zr-xGd Alloy 认领 引用 被引量：2
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作者 Bing-Yu Qian Rui-Zhi Wu +5 位作者 Jian-Feng Sun Jing-Huai Zhang Le-Gan Hou Xiao-Chun Ma Jia-Hao Wang Hai-Ting Hu 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2023年第2期215-228,共14页
The evolution of the microstructure and mechanical properties of alloy system with nominally composition Mg-5Li-1Zn-0.5Ag-0.5Zr-xGd(x=0,1.2,2.4,3.6,4.8,6)is evaluated based on computational phase diagram and correspon... The evolution of the microstructure and mechanical properties of alloy system with nominally composition Mg-5Li-1Zn-0.5Ag-0.5Zr-xGd(x=0,1.2,2.4,3.6,4.8,6)is evaluated based on computational phase diagram and corresponding experimental studies.The results show that grains are significantly refined with the increase of Gd content.The main phases of as-cast alloys areα-Mg,β-Li,AgLi2Mg,and Mg3Gd.With the increase of Gd content,the amounts of Mg3Gd phase andβ-Li phase have been increased.When the Gd content exceeds 3.6 wt%,Mg3Gd phase precipitates in a form of the network at the grain boundaries.The precipitation ofβ-Li can be attributed to the competitive dissolution of Zn,Gd,and Li in Mg.Meanwhile,γ″is formed after the addition of Gd,which grows and transforms intoγ′with the increase of Gd content.In solidification process,stacking faults are formed by solid transformation of partialα-Mg and Mg3Gd.Eventually,with the synergistic effect of Mg3Gd,β-Li,andγ″(orγ′),as the Gd content increasing,the tensile strength of the alloy first increases,then decreases,and the elongation decreases.When the content of Gd is 4.8 wt%,the ultimate tensile strength and yield strength reach the maximum values of 227 MPa and 139 MPa,and the elongation is 18.1%,respectively. 展开更多
关键词 Mg-Li-Zn-Gd alloy Phase diagram Microstructure evolution Mechanical properties
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The Structural Evolutions of ZL109 Alloy and 7050 Alloy in the Semisolid Squeeze Casting Process 认领 引用 被引量：2
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作者 ZHAI Yanbo LIU Changming WANG Kai 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第1期118-122,共5页
The structure evolutions of ZL109 alloy and 7050 alloy were studied in the processes of preparing raw billets by low super heat casting,remelting the raw billets,semisolid forming and heat treating components.The thin... The structure evolutions of ZL109 alloy and 7050 alloy were studied in the processes of preparing raw billets by low super heat casting,remelting the raw billets,semisolid forming and heat treating components.The thin and symmetrical structure was obtained by using low super heat casting process.The eutectic that lied in the raw billet of ZL109 alloy remelted and produced liquid phase in the process of remelting,but to the 7050 alloy,the eutectic of intergranular and the pointedness of grains was remelted to make the grains more uniform and smooth.In the process of semisolid forming,the primaryαand the eutectic inside the ZL109 alloy were separated partly and the grains in the 7050 alloy was conglutinated together.After heat treatment,the eutecticαgrains of ZL109 traveled to primaryαand shaped the white fishing net like organization;the eutectic Si grains assembled into the black massive particles.As to 7050,after heat treatment,αparticles recrystallized and thin grains pattern was obtained. 展开更多
关键词 ZL109 alloy 7050 alloy low super heat casting remelting structure evolution
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In-situ microstructural evolutions of 5Mn steel at elevated temperature in a transmission electron microscope 认领 引用 被引量：2
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作者 Han-bo Jiang Xi-nan Luo +4 位作者 Xiao-yan Zhong Hui-hua Zhou Cun-yu Wang Jie Shi Han Dong 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2017年第11期1109-1114,共6页
The microstructural evolutions of 5Mn steel during various heat treatments have been investiga- ted by in-situ transmission electron microscopy （TEM）. The specimen of 5Mn steel was pre- pared using focused ion beam ... The microstructural evolutions of 5Mn steel during various heat treatments have been investiga- ted by in-situ transmission electron microscopy （TEM）. The specimen of 5Mn steel was pre- pared using focused ion beam （FIB） milling, which allowed the selection of specific morphology of interest prior to the in-situ observation, The complete austenization at 800 ℃ was verified at the atomic scale by minimizing thermal expansion and sample drift in a heating holder based on micro-electro-mechanical-systems. During annealing at 650 ℃, the formation of reverted austen- ite was dynamically observed, while the morphologies of austenite laths of 5Mn steel after in-situ heating were quite similar to that after ex-situ intereritical annealing. During annealing at 500 ℃, the morphological evolution of cementite and associated Mn diffusion were investigated. It was demonstrated that a combination of FIB sampling and high temperature in-situ TEM enables us to probe the morphological evolution and elemental diffusion of specific areas of interest in steel at high spatial resolution. 展开更多
关键词 5Mn steel Focused ion beam milling In-situ observation Microstructural evolution Austenite Cementite
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Effects of Strain Rate,Temperature and Grain Size on the Mechanical Properties and Microstructure Evolutions of Polycrystalline Nickel Nanowires:A Molecular Dynamics Simulation 认领 引用
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作者 RUAN Zhigang WU Wenping LI Nanlin 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2018年第3期251-258,共8页
Through molecular dynamics（MD） simulation, the dependencies of temperature, grain size and strain rate on the mechanical properties were studied. The simulation results demonstrated that the strain rate from 0.05 to... Through molecular dynamics（MD） simulation, the dependencies of temperature, grain size and strain rate on the mechanical properties were studied. The simulation results demonstrated that the strain rate from 0.05 to 2 ns–1 affected the Young＇s modulus of nickel nanowires slightly, whereas the yield stress increased. The Young＇s modulus decreased approximately linearly; however, the yield stress firstly increased and subsequently dropped as the temperature increased. The Young＇s modulus and yield stress increased as the mean grain size increased from 2.66 to 6.72 nm. Moreover, certain efforts have been made in the microstructure evolution with mechanical properties association under uniaxial tension. Certain phenomena such as the formation of twin structures, which were found in nanowires with larger grain size at higher strain rate and lower temperature, as well as the movement of grain boundaries and dislocation, were detected and discussed in detail. The results demonstrated that the plastic deformation was mainly accommodated by the motion of grain boundaries for smaller grain size. However, for larger grain size, the formations of stacking faults and twins were the main mechanisms of plastic deformation in the polycrystalline nickel nanowire. 展开更多
关键词 Effects of Strain Rate Temperature and Grain Size on the Mechanical Properties and Microstructure Evolutions of Polycrystalline Nickel Nanowires A Molecular Dynamics Simulation
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On a Nonlinear Model in Adiabatic Evolutions 认领 引用
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作者 孙杰 路松峰 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第8期207-210,共4页
In this paper, we study a kind of nonlinear model of adiabatic evolution in quantum search problem. As will be seen here, for this problem, there always exists a possibility that this nonlinear model can successfully ... In this paper, we study a kind of nonlinear model of adiabatic evolution in quantum search problem. As will be seen here, for this problem, there always exists a possibility that this nonlinear model can successfully solve the problem, while the linear model can not. Also in the same setting, when the overlap between the initial state and the final stare is sufficiently large, a simple linear adiabatic evolution can achieve O(1) time efficiency, but infinite time complexity for the nonlinear model of adiabatic evolution is needed. This tells us, it is not always a wise choice to use nonlinear interpolations in adiabatic algorithms. Sometimes, simple linear adiabatic evolutions may be sufficient for using. 展开更多
关键词 quantum adiabatic algorithm adiabatic evolution quantum computing
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Evolutions of flow field and heat exchange on equa-torial Pacific surface in El Nino-La Nina cycle 认领 引用
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《Acta Oceanologica Sinica》 SCIE CAS 1997年第2期157-170,共14页
Inthispaper，themonthlyaveragesanddeviationsoftemperature，pressure，zonalwind，specifichumidity，cloudcoverandthecomponentsofheatbudgethavebeenmputedontheequatorial（5．S－3．N）Pacificsurface（EPS）basedonthe2．x2．... Inthispaper，themonthlyaveragesanddeviationsoftemperature，pressure，zonalwind，specifichumidity，cloudcoverandthecomponentsofheatbudgethavebeenmputedontheequatorial（5．S－3．N）Pacificsurface（EPS）basedonthe2．x2．griddataofCOADSfrom1950to1987andtheevolutionsoftheseelementshatebeenprovided．TwofeedbackmechanismsofElNino－LaNinacyclewhichincludethedynamic，therttalandhydrologictlprocessesintheooupledairtseasystemareverified．DuringE1Nino．thepressuregradientandtradewinddecreasedontheEPS，thesensibleandlatentheatexchangesenl 展开更多
关键词 Nino-La Nina cycle surface Pacific El Evolutions La heat flow
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Sedimentary elements,evolutions and controlling factors of the Miocene channel system:a case study of the deep-water Taranaki Basin in New Zealand 认领 引用 被引量：3
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作者 Guangxu Wang Wei Wu +5 位作者 Changsong Lin Quan Li Xiaoming Zhao Yongsheng Zhou Weiqing Liu Shiqin Liang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第11期44-58,共15页
Deep-water channel systems are important petroleum reservoirs,and many have been discovered worldwide.Understanding deep-water channel sedimentary elements and evolution is helpful for deep-sea petroleum exploration a... Deep-water channel systems are important petroleum reservoirs,and many have been discovered worldwide.Understanding deep-water channel sedimentary elements and evolution is helpful for deep-sea petroleum exploration and development.Based on high-resolution 3D seismic data,the Miocene channel system in the deep-water Taranaki Basin,New Zealand,was analyzed by using seismic interpretation techniques such as interlayer attribute extraction and strata slicing.The channel system was divided into five composite channels(CC-I to CC-V)according to four secondary level channel boundaries,and sedimentary elements such as channels,slump deposits,inner levees,mass transport deposits,and hemipelagic drape deposits were identified in the channel system.The morphological characteristics of several composite channels exhibited stark variances,and the overall morphology of the composite channels changed from relatively straight to highly sinuous to relatively straight.The evolution of the composite channels involved a gradual and repeated process of erosion and filling,and the composite channels could be divided into three evolutionary stages:initial erosion-filling,later erosion-filling(multistage),and channel abandonment.The middle Miocene channel system may have formed as a consequence of combined regional tectonic activity and global climatic change,and its intricate morphological alterations may have been influenced by the channel's ability to self-regulate and gravity flow properties.When studying the sedimentary evolution of a large-scale deep-water channel system in the Taranaki Basin during the Oligocene-Miocene,which transitioned from a passive margin to plate convergence,it can be understood how tectonic activity affected the channel and can also provide a theoretical reference for the evolution of the deepwater channels in areas with similar tectonic conversion environments around the world. 展开更多
关键词 deep-water channel system channel geomorphology sedimentary evolution climate and region tectonic activities deep-water Taranaki Basin
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Evolution of energy and metal demand driven by industrial revolutions and its trend analysis 认领 引用 被引量：1
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作者 Jianfeng Yang Yun Yu +2 位作者 Teng Ma Cuiguang Zhang Quan Wang 《Chinese Journal of Population,Resources and Environment》 2021年第3期256-264,共9页
Industrial revolutions have a profound impact on energy and metal demand.Based on technological improvement,industrial transformation,and changes of energy and metal consumption in the United States,this paper identif... Industrial revolutions have a profound impact on energy and metal demand.Based on technological improvement,industrial transformation,and changes of energy and metal consumption in the United States,this paper identified the evolution characteristics of energy and metal demand driven by industrial revolutions,and analyzed the trends of energy and metal demand driven by the fourth industrial revolution which is happening currently.Results indicated that fossil fuels were the major energy sources which boosted up the past three industrial revolutions,whereas their consumption increased at a slowing pace as the economy was growing continually;after the third industrial revolution,the consumption of fossil fuels decoupled gradually with the economic growth.As the industrial structure transformed as the industrial revolutions went on,more and more metals were used in the industries,and the consumption of different metals showed different trends.In recent years,a new technological revolution has surged mainly driven by the overall application of new information technologies.The technological advance in information,new energies,new materials,etc.,will speed up the industrial transformation and exert a deep effect on the demand of energy and metals.It can be inferred that the ratio of clean,non-polluting,renewable energy will rise while the ratio of fossil fuels will drop in the energy demand,and the demand of rare metals will perhaps enter a fast-growing period,while the demand of traditional bulk metals will fluctuate at mid-high levels.Following the new industrial revolution,China should adopt an energy transition strategy of developing low-carbon and free-carbon technologies simultaneously,reinforce the domestic and international metal supply system with the aim of enhancing global governance capability,strengthen the deep development of rich rare metals and broaden the overseas supply channels of scare rare metals. 展开更多
关键词 Technological improvement Industrial revolution Energy Metal resources Evolution
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