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东北大学学报（自然科学版） 1999年第2期20卷 169-172页

作者：郭士文东北大学材料与冶金学院

利用纳米级超显微硬度压痕法研究了具有六方密排结构纯Ｃｄ（９９９９％）的应力应变及加工硬化行为·根据载荷压痕贯穿深度的测量，证明了在Ｃｄ的压痕变形中存在弹性、弹塑性和完全塑性三个阶段，与每个阶段相对应在其载荷压痕深度... 详细信息

利用纳米级超显微硬度压痕法研究了具有六方密排结构纯Ｃｄ（９９９９％）的应力应变及加工硬化行为·根据载荷压痕贯穿深度的测量，证明了在Ｃｄ的压痕变形中存在弹性、弹塑性和完全塑性三个阶段，与每个阶段相对应在其载荷压痕深度曲线上都出现一个斜率的改变，从而可以近似确定金属开始塑性变形的应力范围·其加工硬化指数是随着施加的最大载荷由５ｍＮ时的０１增加到４０ｍＮ时的０３，这主要是和加载的速度有关并满足线性方程·

关键词：压痕硬度镉变形超显微硬度法纳米级

Kinetics of Zr(CrFe)_2 Precipitation in a Beta-quenched and Aged Zr-Cr-Fe Alloy

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Rare Metals 1992年第3期11卷 165-176页

作者： Sun Xi-chen and derek o.northwood Engineering Materials Group,Department of Mechanical Engineering,University of Windsor,Windsor,ontario,Canada N9B 3P4

A Zr-1.15wt% Cr-0.10wt% Fe alloy was beta-quenched from 1050℃ to produce a supersaturated α′-phase, and then heated for varying times at temperatures from 650℃ to 760℃ to precipitate Zr(CrFe)_2.A thermoelectric power(TEP)technique and transmission electron microscopy(TEM)were used to monitor this precipitation *** the Johnson-Mehl-Avrami equation,the TEP results and a line regression method,the activation energy for diffusion and the diffusion coefficient of chromium(and Fe)in α-Zr have been calculated over 650℃～760℃.The temperature dependence of the diffusion coefficient,D_(Cr/α)(cm^2/s)is described at 650℃～760℃ by the relationship *** coarsening of the Zr(CrFe)_2 particles shows a t^(1/2)dependence of mean particle size on aging time,*** a time dependence is typical of coarsening where atom transfer across the interface is rate-controlling.

关键词： Zirconium-base alloy Heat treatment Precipitation Kinetics

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IF钢板镀锌前后热电势的测定

机械工程材料 2001年第2期25卷 32-33页

作者：章跃 Jerry H.Sokolowski derek o.northwood 淮阴工学院江苏淮阴223001 University of Windsor

研究了冷轧 IF钢板镀锌前后的热电势 ( TEP)特性。试验结果表明 :镀锌退火后 ,钢板基体发生再结晶导致 TEP值升高 ,而镀层的形成导致 TEP值下降 ,基体的再结晶起主导作用。并且 ,TEP值存在各向异性 ,这与钢板的织构有关。

关键词：镀锌热电势 IF钢板织构各向异性测量汽车

Evolution of pore systems in low-maturity oil shales during thermal upgrading--Quantified by dynamic SEM and machine learning

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Petroleum Science 2024年第3期21卷 1739-1750页

作者： Jun Liu Xue Bai derek Elsworth Key Laboratory of Deep Underground Science and Engineering(Ministry of Education) Institute of New Energy and Low-Carbon TechnologySichuan UniversityChengdu610065SichuanChina International Quantum Academy Shenzhen518048GuangdongChina Shenzhen Institute of Advanced Electronic Materials Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen518055GuangdongChina Department of Energy and Mineral Engineering Pennsylvania State University ParkPA 16802USA

In-situ upgrading by heating is feasible for low-maturity shale oil,where the pore space dynamically *** characterize this response for a heated substrate concurrently imaged by *** systematically follow the evolution of pore quantity,size(length,width and cross-sectional area),orientation,shape(aspect ratio,roundness and solidity)and their anisotropy—interpreted by machine *** indicate that heating generates new pores in both organic matter and inorganic ***,the newly formed pores are smaller than the original pores and thus reduce average lengths and widths of the bedding-parallel pore ***,the average pore lengths and widths are increased in the bedding-perpendicular ***,heating increases the cross-sectional area of pores in low-maturity oil shales,where this growth tendency fluctuates atomes steady at>300℃.In addition,the orientation and shape of the newly-formed heating-induced pores follow the habit of the original pores and follow the initial probability distributions of pore orientation and ***,limited anisotropy is detected in pore direction and shape,indicating similar modes of evolution both bedding-parallel and *** propose a straightforward but robust model to describe evolution of pore system in low-maturity oil shales during heating.

关键词： Low-maturity oil shale Pore elongation organic matter pyrolysis In-situthermal upgrading Scanning electron microscopy(SEM) Machine learning

Effect of non-uniform swelling on coal multiphysics during gas injection: The triangle approach

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1362-1372页

作者： Yifan Huang Jishan Liu Yaoyao Zhao derek Elsworth Yee-Kwong Leong Department of Chemical Engineering School of EngineeringThe University of Western Australia35 Stirling HighwayWA 6009Australia State Key Laboratory of Coal Resources & Safe Mining China University of Mining& TechnologyBeijing100803China Department of Energy and Mineral Engineering G3 Centre and Energy InstituteThe Pennsylvania State UniversityUniversity ParkPA16802USA

In current dual porosity/permeability models,there exists a fundamental assumption that the adsorption-induced swelling is distributed uniformly within the representative elementary volume (REV),irrespective of its internal structures and transient ***,both internal structures and transient processes can lead to the non-uniform *** this study,we hypothesize that the non-uniform swelling is responsible for why coal permeability in experimental measurements is not only controlled by the effective stress but also is affected by the adsorption-induced *** propose a concept of the swelling triangle composed of swelling paths to characterize the evolution of the non-uniform swelling and serve as a core link in coupled multiphysics.A swelling path is determined by a dimensionless volumetric ratio and a dimensionless swelling *** swelling paths have the same start and end point,and each swelling path represents a unique swelling *** swelling path as the diagonal of the triangle represents the case of the uniform swelling while that as the two perpendicular boundaries represents the case of the localized *** paths of all intermediate cases populate inside the *** corresponding relations between the swelling path and the response of coal multiphysics are established by a non-uniform swelling *** define this method as the triangle approach and corresponding models as swelling path-based *** proposed concept and models are verified against a long-term experimental measurement of permeability and strains under constant effective *** results demonstrate that during gas injection,coal multiphysics responses have a close dependence on the swelling path,and that in both future experiments and field predictions,this dependence must be considered.

关键词： Transient process Heterogeneity Swelling triangle Swelling path Non-uniform swelling coefficient

Applying Machine Learning Approach to Explore Childhood Circumstances and Self-Rated Health in old Age-China and the US,2020-2021

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China CDC weekly 2024年第11期6卷 213-218,I0008-I0013页

作者： Shutong Huo derek Feng Thomas M.Gill Xi Chen Department of Health Society&BehaviorPublic HealthUniversity of CaliforniaIrvineCAUSA Department of Statistics and Data Science Yale UniversityNew HavenCTUS Department of Internal Medicine Yale School of MedicineNew HavenCTUS Department of Health Policy and Management Yale School of Public HealthNew HavenCTUS Department of Economics Yale UniversityNew HavenCTUS.

Introduction:Childhood circumstances impact senior health,prompting the introduction of machine learning methods to assess their individual and collective contributions to senior ***:Using health and retirement study(HRS)and China Health and Retirement Longitudinal Study(CHARLS),we analyzed 2,434 American and 5,612 Chinese participants aged 60 and *** inference trees and forests were employed to estimate the influence of childhood circumstances on self-rated health(SRH).Results:The conventional method estimated higher inequality of opportunity(IoP)values in both China(0.039,accounting for 22.67%of the total Gini coefficient 0.172)and the US(0.067,accounting for 35.08%of the total Gini coefficient 0.191).In contrast,the conditional inference tree yielded lower estimates(China:0.022,accounting for 12.79%of 0.172;US:0.044,accounting for 23.04%of 0.191),as did the forest(China:0.035,accounting for 20.35%of 0.172;US:0.054,accounting for 28.27%of 0.191).Childhood health,financial status,and regional differences were key determinants of senior *** conditional inference forest consistently outperformed others in predictive accuracy,as demonstrated by lower out-of-sample mean squared error(MSE).Discussion:The findings emphasize the need for early-life interventions to promote health equity in aging *** learning showcases the potential in identifying contributing factors.

关键词： collective inequality estimates

A CFD Model to Evaluate Near-Surface oil Spill from a Broken Loading Pipe in Shallow Coastal Waters

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Fluid Dynamics & Materials Processing 2024年第1期20卷 59-77页

作者： Portia Felix Lee Leon derek Gay Stefano Salon Hazi Azamathulla Department of Civil and Environmental Engineering The University of the West IndiesSt.AugustineTrinidad and Tobago National Institute of oceanography and Experimental Geophysics-oGS TriesteItaly

oil spills continue to generate various issues and concerns regarding their effect and behavior in the marine environment,owing to the related potential for detrimental environmental,economic and social *** is essential to have a solid understanding of the ways in which oil interacts with the water and the coastal ecosystems that are located *** study proposes a simplified model for predicting the plume-like transport behavior of heavy Bunker C fuel oil discharging downward from an acutely-angled broken pipeline located on the water *** results show that the spill overall profile is articulated in three major flow *** first,is the source field,i.e.,a region near the origin of the initial jet,followed by the intermediate or transport field,namely,the region where the jet oil flow transitions into an underwater oil plume flow and starts to move horizontally,and finally,the far-field,where the oil re-surface and spreads onto the shore at a significant distance from the spill *** behavior of the oil in the intermediate field is investigated using a simplified injection-type oil spill model capable of mimicking the undersea trapping and lateral migration of an oil plume originating from a negatively buoyant jet spill.A rectangular domain with proper boundary conditions is used to implement the *** Projection approach is used to discretize a modified version of the Navier-Stokes equations in two dimensions.A benchmark fluid flow issue is used to verify the model and the results indicate a reasonable relationship between specific gravity and depth as well as agreement with the aerial data and a vertical temperature profile plot.

关键词： CFD model Navier-Stokes equations projection method water surface oil spill shallow coastal waters

Elucidating microbial iron corrosion mechanisms with a hydrogenase-deficient strain of Desulfovibrio vulgaris

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mLife 2024年第2期3卷 269-276页

作者： Di Wang Toshiyuki Ueki Peiyu Ma Dake Xu derek R.Lovley Electrobiomaterials Institute Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education)Northeastern UniversityShenyangChina Shenyang National Laboratory for Materials Science Northeastern UniversityShenyangChina Department of Microbiology University of MassachusettsAmherstMAUSA

Sulfate-reducing microorganisms extensively contribute to the corrosion of ferrous metal *** is substantial debate over their corrosion *** investigated Fe^(0) corrosion with Desulfovibrio vulgaris,the sulfate reducer most often employed in corrosion *** were grown with both lactate and Fe^(0) as potential electron donors to replicate the common environmental condition in which organic substrates help fuel the growth of corrosive ***^(0) was corroded in cultures of a *** hydrogenase-deficient mutant with the 1:1 correspondence between Fe^(0) loss and H_(2) accumulation expected for Fe^(0) oxidation coupled to H+reduction to H_(2).This result and the extent of sulfate reduction indicated that *** was not capable of direct Fe^(0)-to-microbe electron transfer even though it was provided with a supplementary energy source in the presence of abundant ferrous *** in the hydrogenase-deficient mutant cultures was greater than in sterile controls,demonstrating that H_(2) removal was not necessary for the enhanced corrosion observed in the presence of *** parental H_(2)-consuming strain corroded more Fe^(0) than the mutant strain,which could be attributed to H_(2) oxidation coupled to sulfate reduction,producing sulfide that further stimulated Fe^(0) *** results suggest that H_(2) consumption is not necessary for microbially enhanced corrosion,but H_(2) oxidation can indirectly promote corrosion by increasing sulfide generation from sulfate *** finding that *** was incapable of direct electron uptake from Fe^(0) reaffirms that direct metal-to-microbe electron transfer has yet to be rigorously described in sulfate-reducing microbes.

关键词： electrobiocorrosion electron transfer hydrogen transfer microbial corrosion sulfate-reducing microbes

MXene-derived quantum dots based photocatalysts:Synthesis,application,prospects,and challenges

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Chinese Chemical Letters 2024年第6期35卷 123-133页

作者： Hao Deng Yuxin Hui Chao Zhang Qi Zhou Qiang Li Hao Du derek Hao Guoxiang Yang Qi Wang School of Environmental Science and Engineering Zhejiang Gongshang UniversityHangzhou 310018China Instrumental Analysis Center of Zhejiang Gongshang University Hangzhou 310018China Centre for Technology in Water and Wastewater(CTWW) School of Civil and Environmental EngineeringUniversity of Technology Sydney(UTS)UltimoNSW 2007Australia

In recent years,the emerging two-dimensional material-MXenes has attracted widespread attention in the field of photocatalysis due to its high conductivity,suitable Fermi level,tunable elemental composition,and excellent photoelectric *** zero-dimensional quantum dots(MQDs)derived from 2D MXenes not only inherit the characteristics of MXenes but also exhibit better performance due to the quantum size *** on the above excellent physical and chemical properties,MQDs are often used as co-catalysts of photocatalysts,and show excellent co-catalytic *** the same time,compared with other cocatalysts(precious metals,metal oxides,metal sulfides),it has the advantages of low cost and high ***,understanding the status of MQDs in the field of photocatalysis is crucial for their further *** this review,we summarized the synthesis and modification methods of MQDs in recent years,as well as their photocatalytic applications in H_(2) production,Co_(2) reduction,N_(2) fixation,pollutant degradation,and other *** addition,the challenges and prospects faced by MQDs are also proposed,providing theoretical guidance for the further development of MQD-based photocatalysts.

关键词： MXenes Quantum dots Photocatalysis Composites Environment purification