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Mapping Properties of Certain Oscillatory Integrals on Modulation Spaces

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Acta Mathematica Sinica,English Series 2017年第12期33卷 1647-1658页

作者： mei Fang cheng Hui Hui LIU Ai Wen SUN School of Mathematical and Computer Sciences Anhui Normal University Wuhu 241002 P. R. China

Suppose β1 〉 α1 ≥ 0, β2 〉 α2 ≥ 0 and （k,j） ∈ R^2. In this paper, we mainly investigate the mapping properties of the operator Tα,βf（x,y,z）=∫Q^2f（x-t,y-s,z-t^ks^j）e^-2πit-β1s-β2t^-1-α1s^-1-α2 dtd... 详细信息

关键词： Modulation space singular integral operator Wiener amalgam space

Effect of Thermomechanical Control Processing on Microstructure and Mechanical Properties of Fe-0.2C-1.44Si-1.32Mn Hot Rolled TRIP Steel

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Journal of Iron and Steel Research International 2010年第7期17卷 44-50页

作者： ZHANG Zi-cheng ZHU Fu-xian LI Yan-mei State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

The effect of thermomechanical control processing（TMCP）on microstructure and mechanical properties of Fe-0.2C-1.44Si-1.32Mn hot rolled TRIP steel was investigated through ***-induced transformation and transformation-induced plasticity behavior of retained austenite were *** results show that with multipass deformation,reduction per pass of more than critical deformation in austenite recrystallization region and total reduction of more than 58% in non-recrystallization region and high temperature section of two-phase region,austenite can be refined before γ→α *** is beneficial to obtain refined ferrite grain in final *** obtain fine and uniform microstructure and excellent strength-ductility balance,a three-stage cooling process（laminar cooling-air cooling-ultra-fast cooling）after hot rolling was *** ultimate tensile strength and elongation of the investigated steel can reach 663 MPa and 41%,respectively.

关键词： hot rolled TRIP steel TRIP effect retained austenite transformation-induced plasticity mechanical property

Microstructure and corrosion behavior of the heat affected zone of a stainless steel 308L-316L weld joint

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Journal of Materials Science & Technology 2018年第10期34卷 1823-1834页

作者： cheng Ma Qunjia Peng Jinna mei En-Hou Han Wei Ke Key Laboratory of Nuclear Materials and Safety Assessment. Institute of Metal Research Chinese Academy of Science Shenyang 110016 China University of Chinese Academy of Sciences Beifing 100049 China Suzhou Nuclear Power Research Institute Suzhou 215004 China

Microstructure of the heat affected zone （HAZ） of a 308L-316L stainless steel （SS） weld joint and its corrosion behavior in high temperature water were studied. Peak of the residual strain was observed to approach to the fusion boundary in the HAZ while the strain increased from the top to root areas of the HAZ. The root area of the HAZ shows a lower corrosion resistance in high temperature water than the top and middle areas of the HAZ. This is attributed to a higher level of residual strain in association with a higher density of tangled dislocations in the top area of the HAZ. The results suggest that the residual strain in the HAZ could also promote the SCC through its effect on corrosion, in addition to that on the local microstructure and mechanical property of the steel.

关键词： Stainless steel HAZ Weld joint Corrosion High temperature water

Novel mechanism for the modification of Al_2O_3-based inclusions in ultra-low carbon Al-killed steel considering the effects of magnesium and calcium

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International Journal of Minerals,Metallurgy and Materials 2018年第3期25卷 280-287页

作者： Jing Guo Shu-sen cheng Han-jie Guo Ya-guang mei School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing Key Laboratory of Special Melting and Reparation of High-end Metal Materials University of Science and Technology Beijing

Many researchers have explored the inclusion modification mechanism to improve non-metallic inclusion modifications in steelmaking. In this study, two types of industrial trials on inclusion modifications in liquid steel were conducted using ultra-low-carbon Al-killed steel with different Mg and Ca contents to verify the effects of Ca and Mg contents on the modification mechanism of Al_2O_3-based inclusions during secondary refining. The results showed that Al_2O_3-based inclusions can be modified into liquid calcium aluminate or a multi-component inclusion with the addition of a suitable amount of Ca. In addition, [Mg] in liquid steel can further reduce CaO in liquid calcium aluminate to drive its evolution into CaO–MgO–Al_2O_3 multi-component inclusions. Thermodynamic analysis confirmed that the reaction between [Mg] and CaO in liquid calcium aluminate occurs when the MgO content of liquid calcium aluminate is less than 3 wt% and the temperature is higher than 1843 K.

关键词： inclusions mechanism modification ultra-low carbon Al-killed steel calcium treatment magnesium content

Recent advances in iron-based sulfides electrocatalysts for oxygen and hydrogen evolution reaction

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Chinese Chemical Letters 2024年第1期35卷 181-195页

作者： Jing mei Yuqing Deng Xiaohong cheng Xing Wang Qi Wu State Key Laboratory of New Textile Materials and Advanced Processing Technologies Wuhan Textile UniversityWuhan 430200China Hubei Key Laboratory of Pollutant Analysis&Reuse Technology College of Chemistry and Chemical EngineeringHubei Normal UniversityHuangshi 435002China Hubei Key Laboratory of Low Dimensional Optoelectronic Materials and Devices Hubei University of Arts and ScienceXiangyang 441053China

Increasing environmental pollution and shortage of conventional fossil fuels have made it urgent to develop renewable and clean energy sources. Electrocatalytic water splitting, with its abundant raw materials, simple process, and zero carbon emission, is considered one of the most promising processes for producing carbon-neutral hydrogen which has excellent energy conversion efficiency and high gravimetric energy density. Among them, oxygen evolution reaction (OER) electrocatalysts and hydrogen evolution reaction (HER) electrocatalysts are critical to decreasing the intrinsic reaction energy barrier and boosting the hydrogen evolution efficiency. Therefore, it is imperative to develop and design low-cost, highly active, and stable OER and HER electrocatalysts to lower the overpotential and drive the electrocatalytic reactions. Transition metal sulfides, especially iron-based sulfides, have attracted extensive exploration by researchers as a result of its high abundance in the Earth's crust and near-metallic conductivity. Consequently, in this review, we systematically and comprehensively summarize the progress in the application of iron-based sulfides and their composites as OER and HER electrocatalysts in electrocatalysis. Detailed descriptions and illustrations of the special relationships among their composition, structure, and electrocatalytic performance are presented. Finally, this review points out the challenges and future prospects of iron-based sulfides in practical applications for designing and fabricating more promising iron-based sulfide OER and HER electrocatalysts. We believe that iron-based sulfide materials will have a wide range of application prospects as OER and HER electrocatalysts in the future.

关键词： Iron-based sulfides Electrocatalysts Doping Composites Water splitting

Clarifying the influence of albumin on the initial stages of magnesium corrosion in Hank's balanced salt solution

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Journal of Magnesium and Alloys 2021年第3期9卷 805-817页

作者： Di mei cheng Wang Sviatlana V.Lamaka Mikhail L.Zheludkevich Magnesium Innovation Centre-MagIC Institute of Materials ResearchHelmholtz-Zentrum GeesthachtGeesthacht 21502Germany Institute for Materials Science Faculty of EngineeringKiel UniversityKiel 24103Germany

The corrosion behavior of Mg,a promising biodegradable metallic material,in protein-containing pseudophysiological environment is still not fully *** this work,the influence of albumin on the corrosion behavior of commercially pure magnesium(CP Mg)is investigated during short-term tests in Hank’s Balanced Salt Solution(HBSS).This work focuses on the reactions at the Mg/medium interface from the perspective of the interactions among albumin,media components and *** evolution tests demonstrate that the physiological amount of albumin(40 g L^(-1))accelerates Mg corrosion in HBSS during the first few hours but slows down the degradation *** presence of albumin decreases the concentration of free Ca^(2+)in HBSS and delays formation of protective co-precipitation products on Mg *** evolution of local pH(differs from typically monitored bulk pH)near Mg/medium interface in albumincontaining HBSS is reported for the first *** of local and bulk pH values elucidates the pH buffering effect of albumin during the immersion *** on these results,adsorption,chelating and pH buffering effects are summarized as three important aspects of albumin influence on Mg ***,constant replenishment of medium components is shown to be an influential factor during the Mg corrosion tests.

关键词： Magnesium Corrosion Albumin Biodegradable Local pH

Enhanced the photoelectrochemical performance of Bi_(2)XO_6(X = W, Mo) for detecting hexavalent chromium by modification of CuS

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Journal of Environmental Sciences 2021年第5期33卷 185-195页

作者： Guangxue Zhang Di cheng Mengying Li Chuanqi Feng Huimin Wu He mei Hubei Key Laboratory of Radiation Chemistry and Functional Materials School of Nuclear Technology and Chemistry&BiologyHubei University of Science and TechnologyXianning 437100China Ministry-of-Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules Hubei Key Laboratory of Polymer MaterialsKey Laboratory of regional development and environmental response in Hubei ProuinceFaculty of Resources and Enuironmental ScienceCollege of Chemistry cmd Chemical EngineeringHubei UniversityWuhan 430062China Health Assessment Center Zhejiang Provincial Key Laboratory of Watershed Science and HealthCollege of Public Health and ManagementUniversity TownChashanWenzhou Medical UniversityWenzhou 325035China

In this work, Bi2XO6(X = W, Mo) are synthesized at different temperatures. The results of tests find the optimal temperatures of Bi_(2)WO_(6) and Bi_(2)MoO_(6) are 180 and 160 °C(BW-180, BM-160). Then, BW-180 and BM-160 are further compounded with different contents of CuS. The results of photoelectrochemical(PEC) tests show that CuS can improve the PEC performance of semiconductor materials, and it has better performance when CuS mass fraction is 5%. These maybe the photoelectron potentials generated by Cu S/Bi_(2)XO_(6)(X = Mo, W) heterojunction reduce the combination of photogenerated electrons and holes. When the PEC sensor based on 5%-CuS/BW-180 detects Cr(VI), it has a linear range of 1–80 μmol/L with detection limit of 0.95 μmol/L, while the PEC sensor based on 5%-CuS/BM-160 detects Cr(VI) has a linear range of 0.5–230 μmol/L and a detection limit of 0.12 μmol/L. Thus, 5%-CuS/Bi_(2)XO_(6) has potential application in hexavalent chromium detection.

关键词： Photoelectrochemical Sensor Hexavalent Chromium Heterojunction Detection

Generation of Atomic Cluster State via Adiabatic Evolution of Dark Eigenstates

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Communications in Theoretical Physics 2008年第10期50卷 974-978页

作者： CHEN Ju-mei LI cheng-Zu LIANG Lin-mei CHEN Ping-Xing DAI Hong-Yi Department of Physics National University of Defense Technology Changsha 410073 China

We propose a scheme to generate atomic cluster states of arbitrary configuration in the cavity quantumelectrodynamics (QED) *** process is achieved via adiabatic evolution of dark states,which only requiresadiabatically increasing or decreasing Rabi frequencies of *** it allows the robust implementation of entanglementagainst certain types of *** scheme is relatively decoherence-free in the sense that excited atomic states are neverpopulated and excited cavity photon states can be made negligible in certain conditions.

关键词： cluster state cavity QED dark state decoherence-free static phase difference

New Technology of Multidirectional Loading Rotary Extrusion

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Chinese Journal of Mechanical Engineering 2023年第5期36卷 353-363页

作者： Zhimin Zhang Yong Xue Xing Zhang Beibei Dong mei cheng Zhe Chen National Defense Science and Technology Industry Complex Component Extrusion Technology Innovation Center North University of ChinaTaiyuan 030051China School of Materials Science and Engineering North University of ChinaTaiyuan 030051China

To satisfy the requirements for the precise formation of large-scale high-performance lightweight components with inner ring reinforcement, a new multidirectional loading rotary extrusion forming technology is developed to match the linear motion with the rotary motion and actively increases the strong shear force. Its principle is that the radial force and rotating torque increase when the blank is axially extruded and loaded. Through the synergistic action of axial, radial, and rotating motions, the orderly fow of metal is controlled, and the cumulative severe plastic deformation (SPD) of an“uplift-trowel” micro-area is generated. Consequently, materials are uniformly strengthened and toughened. Simultaneously, through the continuous deformation of a punch “ellipse-circle,” a high reinforcement component is grown on the cylinder wall to achieve the high-quality formation of cylindrical parts or the inner-ring-reinforcement components. Additionally, the efective strain increases with rotation speed, and the maximum intensity on the basal plane decreases as the number of revolutions increase. The punch structure also afects the axial extrusion loading and equivalent plastic strain. Thus, the proposed technology enriches the plastic forming theory and widens the application feld of plastic forming. Furthermore, the formed large-scale high-performance inner-ring-stifened magnesium components have been successfully verifed in aerospace equipment, thereby solving the problems of integral forming and severe deformation strengthening and toughening. The developed technology has good prospects for mass production and application.

关键词： Multidirectional loading Rotary extrusion Inner ring reinforcement Severe plastic deformation Anisotropy