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Electron tomography for sintered ceramic materials by a neural network algebraic reconstruction technique

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Journal of Materials Science & Technology 2022年第5期100卷 75-81页

作者： R.h.Shen y.T.he W.Q.Ming y.Zhang X.D.Xu J.h.Chen Centre for high Resolution Electron Microscopy College of Materials Science and EngineeringHunan UniversityChangsha 410082China

The missing wedge effect in electron tomography introduces various types of artifacts in the tomograms and lowers the reconstruction resolution and *** artifacts produced in tomographic reconstruction of bulk materials can be very severe,particularly for sintered bulk ceramic materials in which there are often nano-pores or pore-like microstructure ***,we report a neural network algebraic reconstruction algorithm with no prior knowledge to perform electron tomography for a sintered SiC material with nano carbon *** results show that the proposed algorithm has a great suppressive effect on the missing wedge artifacts and a high tolerance for *** information in the missing wedge can be partly recovered by this ***,both the shape of the bulk SiC specimen and its irregular inner pore-like features are correctly retrieved in the obtained 3D *** study shows the effectiveness of the neural network algorithm for improving the reconstruction accuracy of electron tomography,in order to reveal sophisticated 3D microstructures generally existing in sintered ceramic materials.

关键词： Neural network Missing wedge Electron tomography Sintered ceramics

FUZZy REGRESSION MODEL TO PREDICT The BEAD GEOMETRy IN The ROBOTIC WELDING PROCESS

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Acta Metallurgica Sinica(English Letters) 2007年第6期20卷 391-397页

作者： B.S. Sung I.S. Kim y. Xue h.h. Kim y.h. Cha Department of Material Engineering Chosun University 375 Seosul-Dong Dong-GuGwangju 501-759 Korea Department of Mechanical Engineering Mokpo National University 61 Dorim-riChungkye-Myun Muan-Gun Jconnam 534-729 Korea Department of Mechanical Engineering Chosun University 375 Seosul-Dong Dong-GuGwangju 501-759 Korea

Recently, there has been a rapid development in computer technology, which has in turn led to develop the fully robotic welding system using artificial intelligence （AI） technology. however, the robotic welding system has not been achieved due to difficulties of the mathematical model and sensor technologies. The possibilities of the fuzzy regression method to predict the bead geometry, such as bead width, bead height, bead penetration and bead area in the robotic GMA （gas metal arc） welding process is presented. The approach, a well-known method to deal with the problems with a high degree of fuzziness, is used to build the relationship between four process variables and the four quality characteristics, respectively. Using these models, the proper prediction of the process variables for obtaining the optimal bead geometry can be determined.

关键词： robotic arc welding bead geometry fuzzy regression modelwelding quality

TEMPERATURE DEPENDENCE OF PERMEABILITy OF Co_(66)Fe_4Mo_2Si_(16)B_(12) ALLOy

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Acta Metallurgica Sinica(English Letters) 2007年第4期20卷 284-286页

作者： y.J. Zhang X.h. Li S. Wang K.y. he College of Material and Metallurgy Northeastern University Shenyang 110004 China College of Aerospace Engineering Shenyang Institute of Aeronautical Engineering Shenyang 110034 China

At different annealing temperatures, the saturation magnetostrictions and the correlation between the permeability μi and the temperature T （μi-T curves） of the Co66Fe4Mo2Si16B12 alloy were investigated using a small-angle magnetization tester and core tester. The experimental results showed that the μi-T curves had different shapes at different ranges of annealing temperature; the permeability μi of the alloy improved with the increase of the annealing temperatures below 460℃; when the alloy was annealed above 480℃, the poor magnetic properties were considered to be caused by larger saturation magnetostriction.

关键词： Co66Fe4Mo2Si16B12 alloy amorphous nanocrystalline alloy permeability saturation magnetostriction

NEW AChIEVEMENTS ON The TheORy AND TEChNOLOGy OF EXPLOSIVE WELDING

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Acta Metallurgica Sinica(English Letters) 2003年第6期16卷 531-537页

作者： C.G. Shi, y.h. Wang, L.G. Cai and C.h. ZhouEngineering Institute of Engineering Corps, PLA University of Science and Technology, Nanjing 210007, China Engineering Institute of Engineering Corps PLA University of Science and Technology

There are four new achievements of this work on the theory and technology of explosive welding.(1) It has been found and defined three kinds of bonding interfaces: big wavy, small wavy and micro wavy, and the micro wavy interface is the best. In a cladding plate, it is for the first time to find that the form of interface presents regular distribution.(2) Although the interface has the features of melt, diffusion and pressure welding in the mean time, the seam and 'hole' brought by the melt weaken the bonding strength of interface greatly, and the effect of melt on interface must be eliminated in explosive welding, so explosive welding is not a melt weld. The diffusion welding is a kind of form of pressure welding, and the diffusion is not the reason of the bonding of interface but the result of interface high pressure. So the diffusion welding cannot also explain the bonding mechanism of it. The experiment and theory make clear that explosive welding is a special pressure one.(3) To get good interface of no melt, explosive charge must be selected on the low limit of welding windows. In explosive welding, the drive plate should be treated as the viscous and plastoelastic body, not incompressible fluid. The bending moment under the explosive welding loading must be greater than that under dynamic limit of drive plate. According to the condition, the lower limit of explosive welding is obtained. It is about 20% less than that obtained by tradition calculation, and suitable for engineering application.(4) It is for the first time to test and study on soil anvil characteristics and change regularity under explosive welding impact loading. Through soil anvil parameter optimization analysis, it is the best for explosive welding with sandy soil of water content 17.00% and density 1.74q/cm3.

关键词： explosive welding bonding interface pressure welding low limit

CORROSION INhIBITION OF X70 STEEL IN SALINE SOLUTION SATURATED WITh CO_2 By ThIOUREA

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Acta Metallurgica Sinica(English Letters) 2008年第1期21卷 65-71页

作者： X. y. he h. y. Deng R. Li X.D. Fei h.y.Wang Z. y. Deng College of Chemistry and Chemical Engineering China West Normal University Nanchong 637002 China

Corrosion monitoring techniques were performed on X7O steel in saline solution saturated with CO2 with and without thiourea additives within the concentration range 5-25 mg/L. It was found that when the concentration of the inhibitors were increased, the inhibitor efficiencies（IE） of thiourea varied with solution temperature and immersion time. The results indicated that thiourea had the highest inhibition efficiency. The potentiondynamic polarization studies revealed that thiourea are mixed-type inhibitor that mainly restrains the anodic process.

关键词： Corrosion Inhibition Thiourea XTO steel

Dual roles of the sacrificial agent in efficient solar-to-chemical production by nonphotosynthetic Moorella thermoacetica

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Science China Chemistry 2025年

作者： Rui Bai Junpeng Li Wei Chen yi he Xudong Zhou Xiaochun Tian Chongyuan Ren Liqi Chen yong Xiao Feng Zhao CAS Key Laboratory of Urban Pollutant Conversion Institute of Urban Environment Chinese Academy of Sciences University of Chinese Academy of Sciences College of Chemistry and Chemical Engineering Xiamen University

The integration of microorganisms and photosensitizers presents a promising approach to chemical production utilizing solar energy. however, the current system construction process remains complex. herein, we introduce a straightforward and efficient solar-to-chemical conversion system that combines the dissolved photosensitizer Eosin y with the non-photosynthetic bacterium Moorella thermoacetica. Under light radiation, acetate production increased to 5.1 μM h-1μM-1catalyst, exceeding the previously reported maximum by 5.9-fold, with a quantum efficiency of 17.6%. The soluble photosensitizer Ey can penetrate the cell and directly engage in intracellular energy metabolism, significantly enhancing intracellular ATP and NADPh/NADP+levels. Within this biohybrid system, sacrificial agent triethanolamine played a dual role:（1） providing continuous photoelectron generation by Eosin y, enhancing intracellular reducing power, and facilitating carbon fixation via the Wood-Ljungdahl pathway; and（2） its oxidation product, formaldehyde, served as a critical intermediate and a direct precursor for methylenetetrahydrofolate in the Wood-Ljungdahl pathway, consequently simplifying reaction steps and markedly boosting acetate *** study provides a simple microorganism-photosensitizer biohybrid system to produce acetate and light on the multifaceted roles of sacrificial agents, paving the development of efficient solar energy conversion with nonphotosynthetic bacteria.

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hetero-deformation promoted strengthening and toughening in BCC rich eutectic and near eutectic high entropy alloys

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Journal of Materials Science & Technology 2023年第15期146卷 1-9页

作者： D.h.Chung J.Lee Q.F.he y.K.Kim K.R.Lim h.S.Kim y.yang y.S.Na Department of Special Alloys Extreme Materials Research InstituteKorea Institute of Materials ScienceChangwonThe Republic of Korea Department of Mechanical Engineering City University of Hong KongKowloon TongKowloonHong KongChina Graduate Institute of Ferrous Technology Pohang University of Science and TechnologyPohangThe Republic of Korea Center for heterogenic Metal Additive Manufacturing Pohang University of Science and TechnologyPohangThe Republic of Korea Department of Materials Science and Engineering City University of Hong KongKowloon TongKowloonHong KongChina

heterostructured eutectic high-entropy alloys(EheAs)have attracted significant attention owing to their novel properties,such as balanced combinations of strength and fracture ***,the toughening/strengthening mechanisms of these EheAs have not been thoroughly *** this study,we developed a series of dual-phase Al_((18–2x))Co_(30)Cr_((11+x))Fe_((11+x))Ni_(3)0(x=-1,0,1)eutectic and neareutectic heAs containing face-centered cubic(FCC)and body-centered cubic(BCC)*** the high amount of BCC,which is referred to as the brittle phase,newly developed EheAs exhibited superior fracture ***,we discovered that a fully eutectic heA exhibited further improvements in both yield stress and fracture toughness,outperforming our off-eutectic and other previously reported *** combining experiments and theoretical models,we demonstrated that the synergistic increase in both strength and toughness in our fully eutectic heA was derived from the high hetero-deformationinduced(hDI)strengthening/toughening associated with a high misorientation angle at the grain/phase boundaries.

关键词： Eutectic high entropy alloy Fracture toughness heterogeneous structure hetero deformation induced strengthening Misorientation angle

Structure and Magnetic Properties of S-doped Mn_3O_4/S Composited Nanoparticles and Mn_3O_4 Nanoparticles

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Journal of Materials Science & Technology 2011年第6期27卷 503-506页

作者： X. he Z.h. Wang D.y. Geng Z.D. Zhang Shenyang National Laboratory for Materials Science Institute of Metal Research and International Centre for Materials Physics Chinese Academy of Sciences Shenyang 110016 China

Composited nanoparticles,consisting of Mn3O4,S-doped Mn3O4 and S,were synthesized by co-precipitation reaction and Mn3O4 nanoparticles were then obtained after removing the pure S from the composited *** Mn3O4-type phase with larger lattice constant a was formed by doping *** fixed temperatures below Curie temperature（TC）,the magnetization of the S-doped Mn3O4/S composited nanoparticles was smaller than that of the Mn3O4 *** blocking temperature was 36.3 and 34.8 K for Sdoped Mn3O4/S composite and Mn3O4 nanoparticles,*** anisotropy field of S-doped Mn3O4/S composite was determined to be about 55.3 kOe.

关键词： Nanostructured materials Chemical synthesis X-ray diffraction Magnetic measurements

STRUCTURE, MAGNETISM AND MAGNETORESISTANCE OF ANNEALED Co/Cu DISCONTINUOUS MULTILAyERS

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Acta Metallurgica Sinica(English Letters) 1997年第6期10卷 465-473页

作者： yan, S.S. Lou, J.X. Zhang, L. Zhang, R.Z. Zhang, y.M. Liu, y.h. Mei, L.M. huang, J. Shandong Univ Jinan China

Co/Cu discontinuous multilayers were prepared by rf-sputtering method under high sputtering power and then annealed at various temperatures in a high vacuum. The structural, magnetic and transport properties were strongly influenced by the annealing temperature. The annealed samples obviously became discontinuous multilayers. A maximum magnetoresistance ratio of 5.6% was obtained under a relatively low saturation field of about 400 (10/4π) A/m at the optimum annealing temperature of 450°C. When the annealing temperature was increased, the resistivity decreased, and the coercive force and the saturation field increased. The magnetoresistance ratio also depended on the thickness of Co and Cu layers. The magnetic and transport properties were explained on the basis of the discontinuous multilayered structure.

关键词： Copper Magnetic properties Multilayers Sputtering Transport properties