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Polyol-Mediated Synthesis of V2O5–WO3/TiO2 Catalysts for Low-Temperature Selective Catalytic reduction with Ammonia

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SSrN 2022年

作者： Lee, Min Seong Choi, Yeong Jun Bak, Su-Jeong Son, Mingyu Shin, Jeehoon Lee, duck Hyun Green Materials and Processes R&D Group Korea Institute of Industrial Technology Ulsan44413 Korea Republic of

We reported a facile synthetic process to obtain highly efficient selective catalytic reduction catalysts by adopting the polyol process, and the prepared catalyst demonstrated high nitrogen oxide (NOx) removal efficiency of 96% at 250 °C. The small catalyst size (~10 nm) enabled an increase in surface area and catalytic acid sites of the catalyst surface. The NOx removal efficiencies at temperatures between 200 and 250 °C were enhanced by approximately 30% compared to the catalysts prepared using the conventional impregnation method. The NH3temperature-programmed desorption and H2-temperature-programmed reduction results confirmed that the polyol process provided more surface acid sites generated at low temperatures and enhanced the redox ability. The in situ Fourier-transform infrared spectra further elucidated the fast absorption of NH3 and its reduction with NO and O2 on the prepared catalyst surfaces. © 2022, The Authors. All rights reserved.

关键词： Temperature

Effect and Mechanism of Mo on Aging Precipitation and Corrosion Behavior of Σ Phase in Super Austenitic Stainless Steel

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SSrN 2023年

作者： Hu, Qunkun du, Huayun Hou, Lifeng Wei, Yingwei Liu, Xiaoda Wei, Huan Wang, Qian Department of Materials Science and Engineering Taiyuan University of Technology Taiyuan030024 China Aluminum-Magnesium Based New Material R&D Co. Ltd. Xing Xian County Economic and Technological Development Zone Lvliang035300 China

Combining microstructure characterization and electrochemical corrosion, the influence of σ phase precipitation behavior and Mo element corrosion resistance of three super austenitic stainless steels, 904L, 254SMo and AL-6XN, was discussed. The increase of Mo element content will significantly increase the precipitation of σ phase, expand the Cr-poor and Mo-poor regions, and enhance the tendency of intergranular corrosion after aging. In addition, the increase of Mo element content will significantly improve the performance of the surface passivation film, but it does not prevent the occurrence of intergranular corrosion due to the increase of the precipitation tendency of the σ phase. © 2023, The Authors. All rights reserved.

关键词： Intergranular corrosion

An Extensive Study of the Effects of Packaging Structure and Material Properties on reliability of Advanced Packages by Charactering the Stress Singularities at Interface Corners

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An Extensive Study of the Effects of Packaging Structure and...

Electronics Packaging technology Conference (EPTC)

作者： Guang-Chao Lyu Bin Chen Xin-Ping Zhang Min-Bo Zhou Chang-Bo Ke Yiu-Wing Mai School of Materials Science and Engineering and Guangdong Provincial Engineering Technology R&D Center of Electronic Packaging Materials and Reliability South China University of Technology Guangzhou China Department of Mechanical Engineering The Hong Kong Polytechnic University Hong Kong

This paper presents a new approach to acquiring in-plane solutions for the stress singularities at internal junctions where multiple elastic isotropic materials meet, and then establishing the correlation between the singular stress field and the failure of electronic package structures. Extensive analyses have been conducted on the order of the stress singularities in relation to the material properties and interface angles, which address an important yet controversial issue regarding the utilization of the stress singularity for electronic package reliability assessment. The results obtained through calculating the stress singularity orders are further validated using finite element analyses. The basic findings indicate that the analyses of the singularity order can serve as an initial approach to evaluate structural design and system reliability. However, relying solely on the calculations of the stress singularity order is insufficient when exploring the variations in material parameters. despite that, the calculations of the order of stress singularity still provide valuable guidance for electronic package design and help develop more robust and reliable packaging solutions for integrated circuit devices.

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Twinned dendrites in Tial Alloys

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SSrN 2023年

作者： Zhang, Fuqiang Song, Yi Ge, Gengwu Xu, Leming ding, Xianfei He, Jianping Liang, Yongfeng Lin, Junpin State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing100083 China Cast Titanium Alloy R&D Center Beijing Institute of Aeronautical Materials Beijing100095 China

The existence of twinned dendrites in as-cast TiAl alloys was revealed for the first time. The microstructural morphologies and crystallographic characteristics of the twinned dendrites were clarified and compared with those of Al alloys. For the β-solidified TiAl alloy with the primary phase being β, the dendrites were separated by irregular twinned boundaries. The twinned relationship between the two sides of the twinned boundary was confirmed via {111} pole figures from different perspectives. When the primary solidification phase was α, the twinned dendrites disappeared, which can be attributed to the difference in the atomic structure. However, the γ-solidified TiAl alloy shows typical features of twinned dendrites in terms of the straight {111} twinned plane and arrangements of the γ dendrites. The initial discussion involves the mechanism behind the formation of twinned dendrites, which is related to the intrinsic atomic structure and bonding type of TiAl alloys. © 2023, The Authors. All rights reserved.

关键词： Solidification

Strengthening, Strain Hardening and Fracture of Heat-Treated Interstitial-Free Steel with Massive Ferrite Conceptualizing the Interface Controlled reaction Phenomena

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SSrN 2024年

作者： Yadav, Sandeep Syed, Badirujjaman Ghosh, Sadhan Metallurgical and Materials Engineering Indian Institute of Technology Uttarakhand Roorkee247 667 India Global R&D ArcelorMittal USA 3001 E Columbus Dr. East ChicagoIN46312 United States

Interstitial-free steel is extremely soft and ductile with allotriomorphic ferrite in the microstructure as a diffusional transformation product of austenite. In order to alter the mechanical property, the present work performed austenitization of the steel at 925°C for 5 min and thereafter a rapid water quenching, resulting in massive ferrite. The yield strength (86 MPa) and ultimate tensile strength (181 MPa) increased to 362 MPa and 531 MPa, respectively, along with 18% ductility. The statistically stored dislocation density and substructures (sub-boundaries, cells) at the grain body contributed 68% of the yield strength. The strain hardening was observed to be lower than that with allotriomorphic ferrite, due to heterogeneous deformation of the substructures, causing an inhomogeneous distribution of geometrically necessary dislocation density at the bulk. The preferential localization of strain at cell walls initiates cracks by the de-cohesion of massive grains. The cell-substructure conceived by massive ferrite therefore has a strong role both in strain hardening and fracture. The larger the grain size is, the more the cell-substructure is, dictated by an interface-controlled growth of austenite to massive ferrite. The atomic jump at the transformation interface is usually considered to be an equilibrium process;meaning slow, not standing with the so-called faster growth kinetics of an interface-controlled reaction. In order to bridge the gap, the present work demonstrates a slip deformation at the transformation interfaces for fast-tracking the lattice reconstruction of massive ferrite from austenite, a novel. © 2024, The Authors. All rights reserved.

关键词： Cells

Experimental investigation on the distribution uniformity and pressure drop of perforated plate distributors for the innovative spray-type packed bed thermal storage

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Particuology 2022年第2期20卷 60-73页

作者： Lin Lin Liang Wang Xipeng Lin Ningning Xie Haisheng Chen Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Dalian National Laboratory for Clean Energy Chinese Academy of SciencesDalian 116023China National Energy Large Scale Physical Energy Storage Technologies R&D Center of Bijie High-tech Industrial Development Zone Guizhou 551712China Institute of Science and Technology China Three Gorges CorporationBeijing 100038China

As an innovative thermal energy technology,the spray-type packed bed has advantages of high efficiency and low cost.A liquid distributor is the key component for the spray-type packed bed for scattering heat-transfer liquid drops *** this study,the distribution performance and pressure drop of the perforated plate distributors of different orifice diameters were studied *** experimental results indicate that orifice diameter has a greater effect on the distribution performance compared to flow *** an increase in flow rate,the flow pattern through the distributor changes from the uncovered drop to the covered drop and then to the jet *** covered drop pattern shows the best performance with a good distribution and a small pressure drop simultaneously,which is the design and optimization principle of the distributor for a spray-type packed bed.

关键词： Spray-type packed bed Perforated plate distributor distribution Pressure drop Thermal energy storage

research on the Structural Mechanical response of Wind Turbine Blade Subcomponent Under Torsional Load

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SSrN 2024年

作者： Li, Chengliang Zhang, Leian Wang, Jihui Zhang, denggang Guo, Wenzhe R&D Center Sinoma Wind Power Blade Co. Ltd China School of Mechanical Engineering Shandong University of Technology Zibo255049 China School of Materials Science and Engineering Wuhan University of Technology Wuhan430070 China

In this study, we analyze the structural mechanical behavior of the central airfoil section (50m-75m) of an 85.8-meter large wind turbine blade under pure torsional loads. Initially, a numerical model tailored for torsional stress analysis is developed using a hybrid shell-solid element approach. Subsequently, we propose a torsional testing methodology for subcomponents tailored to real-world operating conditions and design a specialized loading apparatus for field testing. Through the integration of numerical simulations and field test data, we observe that the subcomponent's response to pure torsional loading exhibits a multidimensional nonlinear behavior. Notably, the main beam and the trailing edge are critical in withstanding the torsional forces. The analysis reveals that the global strains on the pressure side (PS) and suction side (SS) are antithetical, with the SS demonstrating significant resistance to torsional stresses. The torsional loads are eventually manifested as chordal tensile and compressive forces that alternate along the subcomponent's span. Furthermore, by incorporating progressive failure theory into our numerical model, we detect surface deformations in the core plate at the root when the tip experiences torsional loads. This response propagates to the full-scale blade, leading to localized buckling in the transition region at the root, which precipitates adhesive delamination and ultimately compromises the structural integrity. © 2024, The Authors. All rights reserved.

关键词： Numerical models

research and application of supramolecular gel plugging agent in abnormal pressure reservoir 10

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Research and application of supramolecular gel plugging agen...

10th Global Conference on materials Science and Engineering, CMSE 2021

作者： Baletabieke, B. Gu, Y.X. Zhou, T. duan, d.X. Liu, J.T. Kong, X.J. Qian, F. Li, W.J. Zhong, Z. Xiang, Y. Jing, N. Li, J.Y. CNPC Engineering Technology R&D Company Limited Beijing102206 China China National Oil and Gas Exploration and Development Corporation Beijing100034 China

The Aktobe project is the largest oil and gas producing area of PetroChina in Central Asia. However, after years of exploitation, the pressure of the reservoir has dropped, making it difficult to increase the production of a single well. Both the Kenkyak block and North Troyes block of the project have induced fractured leakage, and frequent leakage affects safe and efficient drilling and completion operations and production. Therefore, the research on leakage prevention and control technology is very necessary. This article focuses on the characteristics of the cracks in the high-pressure area of the Kenkyak block and the cracks in the low-pressure area of the North Troyes block. Aiming at the fracture characteristics of the high-pressure zone in the Kenkyak block and the low-pressure zone in North Troyes block, and taking advantage of the synergistic effect of supramolecules, a supramolecular plugging-while-drilling agent was developed based on the deformable fiber composite gel. It forms a strong adhesion plugging layer on the inner wall of the leakage channel through the strong adhesion force, and it achieves a good plugging effect. The 300-500md sand disc bearing pressure could reach 700psi when adding 3% agent, and the bearing pressure of 3-5d permeability sand disc could reach above 450psi. A supramolecular static plugging agent was also developed based on the dilatant gel. It is rich in strong shear reversible gel with supramolecular structure, which guarantees its pumpability and plugging performance. The effective rate of one-time plugging is over 80%, and the viscosity is greatly reduced after the gel is broken for 72hr, which benefits the reservoir protection. © 2021 Institute of Physics Publishing. All rights reserved.

关键词： Adhesion

degradation Behavior of Chromium-Coated Zirconium Cladding Under High-Temperature Oxidation According to the Coating Microstructure

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SSrN 2024年

作者： Jung, Tae-Sik Jang, Hoon Cho, Yong Ki Jang, dongchan Materials Development Section Nuclear Fuel Technology Department KEPCO Nuclear Fuel Daejeon34057 Korea Republic of Department of Nuclear and Quantum Engineering Korea Advanced Institute of Science and Technology Daejeon34141 Korea Republic of Customized Manufacturing R&D Department Korea Institute of Industrial Technology Seohaean-ro Gyeonggi-do Siheung-si113-58 Korea Republic of

In 2011, the Great East Japan Earthquake and tsunami caused a hydrogen explosion at the Fukushima daiichi nuclear power plant, which exposed radioactive materials to the atmosphere and had a very negative impact on the nuclear power industry. Since then, efforts have intensified around the world to make nuclear power safer. Accident-tolerant fuel (ATF) is being developed to prevent the rapid oxidation of zirconium cladding, which directly causes hydrogen explosions. ATF research can be divided into two main approaches: changing the cladding material, or coating the surface of the cladding. Coatings are easier to commercialize and apply to existing nuclear power plants, so most vendors have focused on this approach. Chromium is a popular coating medium because of its superior properties such as a low oxidation rate and excellent adhesion. Therefore, research has been focused on suppressing the rapid oxidation of zirconium cladding in the event of an accident by adding a chromium coating with an appropriate thickness in terms of both economy and effectiveness. Even if the thickness of the coating is fixed, the penetration of oxidizing substances can be further delayed by improving the microstructure of the chromium coating, such as by reducing the grain boundary area. In this study, chromium-coated zirconium cladding tubes were fabricated by the arc ion plating process. The microstructure of the chromium coating was adjusted by varying the negative voltage (0–125 V), which in turn controlled the velocity at which the chromium ionic particles hit the surface of the cladding tube. Experiments were then performed in a high-temperature steam environment to determine the optimal microstructure for high-temperature oxidation resistance. The development of various material degradation phenomena that occurred during high-temperature oxidation was observed to identify the oxidation mechanism and the main factors of the microstructure that affect the zirconium oxidation rate. ©

关键词： Thermooxidation