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Tungsten 2025年第1期7卷 80-87页

作者： Fang-Qian Wang Yin zhang Wei-Wei Wang Mei-Qian Fu Hong-bing Mo Wei-Dong Yu Chao Liu Jun Yan College of Chemistry and Chemical Engineering Central South University Junior Education Department Changsha Normal University School of Science Hunan University of Technology and Business

Arsenic-vanadium polyoxometalates（POMs） represent a family of tremendous potential catalysts owing to their peculiar physical and chemical *** in CO2conversion,using POMs to catalyze the conversion of CO2and epoxide into chemical intermediates is the research ***,A new family number of arsenic-vanadium POMs,[N（CH3）4]4[As8V12O38（H2O）]·2H2O({As8V12O38}),was reported and characterized by single-crystal X-ray diffraction,fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,*** from other allotropicity,{As8V12O38}shows a different structure pattern with an I-43d *** obtained {As8V12O38} was employed as a catalyst for the *** initial catalytic reaction confirmed that {As8V12O38} can catalyze the formation of epoxy carbonate by using 1.01 kPa CO2and epoxide at 70℃.Furtherly,when added amine in the catalytic system,oxazolidinone could be obtained by high yields,which provides an efficient way to convert CO2into profitable ***,a possible catalytic reaction mechanism was proposed by using different characterization analyses.{As8V12O38} first catalyzes the epoxide and CO2to form an epoxy carbonate and then catalyzes epoxy carbonate and benzylamine into oxazolidinone.

关键词： Arsenic CO2 conversion Oxazolidinone Polyoxometalates Vanadium

Oxygen transfer in human carotid artery bifurcation

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Acta Mechanica Sinica 2007年第3期23卷 305-309页

作者： z. G. zhang Y. b. Fan X. Y. Deng Dalian University of Technology Dalian 116023 China Department of bioengineering Beihang UniversityBeijing 100083 China

Arterial bifurcations are places where blood flow may be disturbed and slow recirculation flow may occur. To reveal the correlation between local oxygen transfer and atherogenesis, a finite element method was employed to simulate the blood flow and the oxygen transfer in the human carotid artery bifurcation. Under steady-state flow conditions, the numerical simulation demonstrated a variation in local oxygen transfer at the bifurcation, showing that the convective condition in the disturbed flow region may produce uneven local oxygen transfer at the blood/wall interface. The disturbed blood flow with formation of slow eddies in the carotid sinus resulted in a depression in oxygen supply to the arterial wall at the entry of the sinus, which in turn may lead to an atherogenic response of the arterial wall, and contribute to the development of atherosclerotic stenosis there.

关键词： Atherosclerosis Carotid artery Secondary flow Mass transfer

Influence of lanthanum as additive and post-treatment on the corrosion protection properties and surface morphology of mild steel chemically treated by a cerium conversion coating

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Journal of Rare Earths 2018年第10期36卷 1112-1120页

作者： z.Mahidashti b.Ramezanzadeh Department of Surface Coatings and Corrosion Institute for Color Science and Technology (ICST)

The influence of cerium conversion coating（CeCC） modified by lanthanum in two forms of additive and post-treatment solution on the corrosion resistance, surface morphology and surface chemistry of the mild steel was studied. Corrosion resistance was evaluated by electrochemical impedance spectroscopy,while the scanning electron microscopy, X-ray photoelectron spectroscopy and contact angle test were employed to investigate the surface characteristics. Results reveal that the CeCC post-treated by lanthanum containing solution gives rise to the deposition of a crack free and uniform conversion coating with enhanced corrosion resistance on the steel surface. Also, the surface free energy is increased after post-treatment.

关键词： Surface treatment Corrosion resistance XPS AFM SEM/EDS Surface free energy

Microscopic stresses in carbon nanotube reinforced aluminum matrix composites determined by in-situ neutron diffraction

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Journal of Materials Science & Technology 2020年第19期54卷 58-68页

作者： X.X.zhang J.F.zhang z.Y.Liu W.M.Gan M.Hofmann H.Andrä b.L.Xiao z.Y.Ma Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China German Engineering Materials Science Centre at MLz Helmholtz-Zentrum GeesthachtD-85747 GarchingGermany Heinz Maier-Leibnitz zentrum(MLz) Technische Universität MünchenD-85747 GarchingGermany Fraunhofer Institute for Industrial Mathematics Fraunhofer-Platz 1Kaiserslautern 67663Germany

One of the most desired strengthening mechanisms in the carbon nanotube reinforced aluminum matrix composites(CNT/Al)composites is the load transfer strengthening mechanism(LTSM).However,a fundamental issue concerning the LTSM is that quantitative measurements of load partitioning in these composites during loading are very *** this study,in-situ neutron diffraction study on the tensile deformation of the 3 vol.%CNT/2009 Al composite and the unreinforced 2009 Al alloy was ***{311}and{220}diffraction elastic constants(DECs)of the 2009 Al alloy were *** those DECs the average stress in the 2009 Al matrix of the composite was *** the average stress in the CNTs was separated by using the stress equilibrium *** homogenization models were also applied to explain the stress evolution in each *** results agree with experimental *** the present case,the average stress in the CNTs reaches 1630 MPa at the yield strength of the composite based on linear regression of the measured data,which leads to an increment of yield strength by about 37 *** the result of this work,an approach to quantify load partitioning in the CNTs is developed for the CNT/Al composites,which can be applied to optimize the mechanical properties of the composites.

关键词： Carbon nanotubes Aluminum matrix composites In-situ neutron diffraction Load partitioning

RESEARCH ON LASER DIRECT DEPOSITION PROCESS OF Ti-6Al-4V ALLOY

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Acta Metallurgica Sinica(English Letters) 2007年第3期20卷 171-180页

作者： S.Y. Gao Y.z. zhang L.K. Shi b.L. Du M.z. Xi H.z. Ji Mechanical Engineering College Yanshan University O~mhuangdao 066004 China beijing General Research Institute for Nonferrous Metals Beijing 100088 China

Laser direct deposition （LDD） of metallic components is an advanced technology of combining CAD/CAM （computer aided design/computer aided manufacturing）, high power laser, and rapid prototyping. This technology uses laser beam to melt the powders fed coaxiaUy into the molten pool by the laser beam to fabricate fuUy dense metallic components. The present article mainly studies the LDD of Ti-6Al-4V alloy, which can be used to fabricate aircraft components. The mechanical properties of the Ti-6Al-4V alloy, fabricated by LDD, are obtained using the tension test, and the oxygen content of used powders and deposited specimens are measured. In the present article, it can be seen that the mechanical properties obtained using this method are higher than the ones obtained by casting, and equal to those got by wrought anneal. One aircraft part has been made using the LDD process. because of this aircraft part, with sophisticated shape, the effect of the laser scanning track on the internal soundness of the deposited part was discussed.

关键词： laser direct deposition Ti-6Al-4V alloy mechanical property depositing process aircraft component

NUMERICAL SIMULATION OF TEMPERATURE FIELDS IN ELECTROSLAG REMELTING SLAb INGOTS

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Acta Metallurgica Sinica(English Letters) 2008年第4期21卷 253-259页

作者： L.z. Chang b.z. Li Department of Metallurgical Technology Central Iron ＆ Steel Research Institute Beijing 100081 China

The method based on transient heat transfer model is adopted to simulate electro-slag remelting process. The calculated results of the model show that the process is in the quasi-steady state, and the shape of pool remains unchanged when the height of ingot is approximately 2.5-3 times the thickness of slab ingot. The change in the shape of pool is found to be strongly dependent on the pattern of melting rate, and hence, the power input; the depth of the molten pool increases with the increase in melting speed. It is concluded that a transient heat transfer model has to be used to obtain reliable input information for the entire, operatina time.

关键词： ESR Slab ingot Mathematical model Shape of molten metal pool

Acceptor concentration dependent Fo?rster resonance energy transfer in nanocrystal-molecule complexes revealed by spectral analysis

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Optoelectronics Letters 2025年

作者： Rongxin zhang zixiang zHOU Lei WANG Xin zhang Ying LIANG Guijie LIANG Hubei Key Laboratory of Low Dimensional Optoelectronic Materials and Devices， Hubei University of Arts and Science

A nanocrystal-molecule complex composed of CdSe donor and Rhodamine b (Rhb) acceptor is prepared to investigate the effect of accepter-donor ratio on the Fo?rster resonance energy transfer (FRET) process. To highlight the FRET process， the energy level alignment between CdSe and Rhb is purposefully designed and CdSe nanocrystal is coated with a wide band-gap znS shell. The carrier dynamics is observed via combined spectral analysis. The results reveal clear FRET process between the CdSe donor and Rhb acceptor. The FRET is enhanced by increasing Rhb/CdSe ratio and a gradual saturation will be present at high Rhb concentration.

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Low‑Temperature Fabrication of Stable black‑Phase CsPbI_(3)Perovskite Flexible Photodetectors Toward Wearable Health Monitoring

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Nano-Micro Letters 2025年第3期17卷 232-245页

作者： Yingjie zhao Yicheng Sun Chaoxin Pei Xing Yin Xinyi Li Yi Hao Mengru zhang Meng Yuan Jinglin zhou Yu Chen Yanlin Song College of Chemistry and Pingyuan Laboratory Zhengzhou UniversityZhengzhou 450001People’s Republic of China Key Laboratory of Green Printing Institute of ChemistryChinese Academy of SciencesBeijing 100190People’s Republic of China Key Laboratory of bio‑Inspired Materials and Interfacial Science Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190People’s Republic of China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049People’s Republic of China

Flexible wearable optoelectronic devices fabricated fromorganic–inorganic hybrid perovskites significantly accelerate the developmentof portable energy,biomedicine,and sensing fields,but their poor thermal stabilityhinders further ***,all-inorganic perovskites possessexcellent thermal stability,but black-phase all-inorganic perovskite filmusually requires high-temperature annealing steps,which increases energy consumptionand is not conducive to the fabrication of flexible wearable *** this work,an unprecedented low-temperature fabrication of stable blackphaseCsPbI3perovskite films is demonstrated by the in situ hydrolysis reactionof diphenylphosphinic chloride *** released diphenyl phosphateand chloride ions during the hydrolysis reaction significantly lower the phasetransition temperature and effectively passivate the defects in the perovskitefilms,yielding high-performance photodetectors with a responsivity of 42.1 AW−1 and a detectivity of 1.3×10^(14)***,high-fidelity imageand photoplethysmography sensors are demonstrated based on the fabricated flexible wearable *** work provides a newperspective for the low-temperature fabrication of large-area all-inorganic perovskite flexible optoelectronic devices.

关键词： In situ hydrolyzation Low-temperature processing All-inorganic perovskite Flexible photodetectors Health monitoring

On Temperature and Strain Rate Dependent Strain Localization behavior in Ti-6.5Al-3.5Mo-1.5zr-0.3Si Alloy

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Journal of Materials Science & Technology 2013年第3期29卷 273-278页

作者： b.zhang L.M.Lei X.L.Jiang z.M.Song X.Huang G.P.zhang Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) Northeastern University Titanium Alloys Laboratory Beijing Institute of Aeronautical Materials AVIC commercial Aircraft Engine Co. Ltd. Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences

Deformation behaviors of Ti-6.5Al-3.5Mo-1.5zr-0.3Si alloys with α/β lamellar structure were investigated systematically at different temperatures from room temperature to 950 ~C and different strain rates. Results reveal that when the deformation temperature is higher than a critical temperature of 600℃, an evident transition of deformation behavior from localized shear banding to α/β lamella kinking, flow softening and temperature/strain rate-dependent peak flow stress occurred in the alloy. The critical conditions for the occurrence of internal cracking and strain localization behavior associated with temperature and strain rate were determined.

关键词： Titanium alloy Hot working Temperature Strain rate Shear band

ANALYSIS OF TEMPERATURE DEPENDENCE OF PHASES AND SURFACE MORPHOLOGY OF bi_2Sr_2Ca_(x-1)Cu_xO_y THIN FILMS USING REACTIVE CO-DEPOSITION METHOD

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Acta Metallurgica Sinica(English Letters) 2007年第3期20卷 199-204页

作者： z.H. zou X.M. Yu b.S. zhang Y. Qi School of Science Northeastern University Shenyang 110004 China

A reactive co-deposition processing for obtaining high-quality single-phase bi2Sr2Cax-1CuxOy （bi2212） thin films has been investigated using molecular beam epitaxy （MbE） with 2.7 ×10^-3pa ozone gas introduction for oxidation. The thin films with a constant composition of almost 2 ： 2 ： 1 ： 2 were designed to be fabricated at the substrate temperature between 675 and 780℃, the substrate temperature dependence of the surface morphology and the emergence phases were investigated in detail. A noticeable result is that the distribution of Cu element in the thin films is sensitively changed with the substrate temperature. At 750℃ it is inclined to locate in the periphery of each grain through the diffusion process. At 780℃ the Cu-compositional fluctuation brought around the dendritic crystal growth in the thin films. below 705℃, the bi2212 single-phase cannot be achieved in the thin films.

关键词： bi2212 (bi2Sr2Cax-1CuxOy) single-phase dendritic growth substrate temperature