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Influence of pre-torsion and low-temperature aging on ZK60 magnesium alloy

Journal of Magnesium and Alloys 2025年

作者： Hu, Jiaqi Liang, Xinyue Shi, Weishuai Gao, Hong School of Chemical Engineering and Technology Tianjin University Tianjin 300350 China Engineering Research Center for Magnesium-based New Material Center for Advancing Materials Performance from the Nanoscale State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University Xi'an710049 China Zhejiang Institute of Tianjin University Zhejiang Ningbo315201 China Tianjin Key Laboratory of Chemical Process Safety and Equipment Technology Tianjin 300350 China

Magnesium alloys are widely used in aerospace and automotive industries due to their lightweight. However, their poor fatigue performance limits the broader application, especially in dynamic stress environments. This study explores novel coupled pretreatments of free-end large-angle pre-torsion and low-temperature aging to improve the fatigue resistance of rolled ZK60 magnesium alloy. STA (pre-torsion followed by low-temperature aging) and SAT (low-temperature aging followed by pre-torsion) samples were prepared to investigate the influences of pretreatment coupling sequences. The results of microstructure characterization reveal that pre-torsion significantly enhances the formation of tensile twins and introduces a gradient microstructure with increased dislocation density from the center to the edges. STA process resulted in the highest twinning area fraction of 35.2 % and a kernel average misorientation of 0.94 at the edge. Mechanical testing demonstrated that the coupled pre-treatment obtained a better combination of strength and plasticity, significantly improved the yield strength in the compression stage, and increased the tensile-compressive yield ratio to >0.9. In the low-cycle fatigue test, the STA samples exhibited lower cyclic mean stress, a smaller cyclic hardening trend, and better hysteretic symmetry, leading to an improvement in fatigue life of up to 256 %. The findings suggest that the combined pre-torsion and low-temperature aging treatments offer a promising approach to enhance the mechanical properties and fatigue resistance of ZK60 magnesium alloy, making it suitable for structural applications in demanding environments. © 2025

关键词： Magnesium alloys

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Mesoporous Cumn2o4 Nanoframework as an Efficient Catalyst for the Synthesis of Benzimidazole Derivatives Through Air Oxidative Coupling in Water

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SSRN 2024年

作者： Chai, Kejie Xia, Weida Chen, Handan Su, Weike Xu, Weiming Su, An Key Laboratory of Pharmaceutical Engineering of Zhejiang Province National Engineering Research Center for Process Development of Active Pharmaceutical Ingredients Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals Zhejiang University of Technology Hangzhou310014 China College of Material Chemistry and Chemical Engineering Hangzhou Normal University Hangzhou311121 China College of Chemical Engineering Zhejiang University of Technology Hangzhou310014 China

Mixed-metal oxide (MMO) CuMn2O4 nanoframework with a mesoporous structure was synthesized. The advantages of this mesoporous MMO are its large specific surface area, uniform pore size, and various metal valence states. MMO CuMn2O4 nanoframework showed efficient catalytic activity in the oxidative coupling of 2-amino/hydroxy/mercaptoanilines with various alcohols in the preparation of benzimidazoles, benzoxazoles, and benzothiazoles using water as the sole solvent in high yields. The efficient catalytic activity is mainly attributed to large specific surface area, increased number of active sites, solvent reorganization between the pores of mesoporous CuMn2O4 nanoframework, and the various electronic states of the copper and manganese ions (Cu+, Cu2+, Mn3+, Mn4+) due to the Jahn-Teller effect. This research provides new insights into improving the catalytic performance of catalyst for the synthesis of nitrogen-containing five-membered ring compounds. © 2024, The Authors. All rights reserved.

关键词： Catalyst activity

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Silver modified Cu/SiO2 catalyst for the hydrogenation of methyl acetate to ethanol

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Chinese Journal of Chemical engineering 2020年第6期28卷 1612-1622页

作者： Zhiheng Ren Muhammad Naeem Younis Hui Zhao Chunshan Li Xiangui Yang Erqiang Wang Gongying Wang Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu 610041China National Engineering Laboratory for VOCs Pollution Control Material&Technology University of Chinese Academy of SciencesBeijing 101408China CAS Key Laboratory of Green Process and Engineering State Key Laboratory of Multiphase Complex SystemsThe National Key Laboratory of Clean and Efficient Coking TechnologyBeijing Key Laboratory of Ionic Liquids Clean ProcessInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China Zhongke Langfang Institute of Process Engineering Langfang 065000China Zhongke Langfang Institute of Process Engineering Zhengzhou 450000China School of Chemical Science University of Chinese Academy of SciencesBeijing 100049China

A series of silver modified Cu/SiO2 catalysts were synthesized with ammonia-evaporation method and applied in vapor-phase hydrogenation of methyl acetate to *** influence of additive‘Ag’on the structural evolution of catalyst was systematically studied by several characterization techniques,such as N2 adsorption–desorption,N2O titration,PXRD,FTIR,in-situ FTIR,H2-TPR,H2-TPD,XPS and *** showed that incorporation of a small amount of Ag could enhance the structural stability,and the strong interaction between Cu and Ag species was conducive to increase the dispersion of copper species and create a suitable Cu+/(Cu0+Cu+)ratio,which was proposed to be responsible for the improved catalytic *** maximum conversion of MA(94.1%)and selectivity of ethanol(91.3%)over optimized Cu-0.5 Ag/SiO2 and 120 h on stream without deactivation under optimal conditions demonstrates its excellent stability.

关键词： Copper Silver Hydrogenation Methyl acetate Ethanol Kinetic

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Dietary zero-dimensional fullerene supplementation improves the meat quality,lipid metabolism,muscle fiber characteristics,and antioxidative status in finishing pigs

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Animal Nutrition 2022年第4期11卷 171-180页

作者： Simeng Liao Guang Liu Bie Tan Ming Qi Xin Wu Jianjun Li Xiaoqing Li Changfeng Zhu Jiamei Huang Shuo Zhang Yulong Tang Yulong Yin Laboratory of Animal Nutritional Physiology and Metabolic Process Key Laboratory of Agro-Ecological Processes in Subtropical RegionNational Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry ProductionInstitute of Subtropical AgricultureChinese Academy of SciencesChangsha410125China University of Chinese Academy of Sciences Beijing100008China College of Animal Science and Technology Hunan Agricultural UniversityChangsha410128China Xiamen Funano New Material Technology Company LtdXiamen361005China Yunnan Southwest Agriculture and Animal Husbandry Group Kunming650217China

With the increasing demand for high-quality pork,more nutritional substances have been studied for the regulation of meat ***-dimensional fullerenes(C60)can modulate the biological behavior of a variety of cell lines and *** this study,we report the biological effects of C60 on finishing pigs at different concentrations.A total of 24 barrows(Duroc×Large White×Landrace),with an average body weight of 21.01±0.98 kg,were divided into 3 groups and each treated daily with C60(100 or 200 mg per kg feed)or a control diet until the end of the *** results showed that dietary C60 supplementation improved flesh color,marbling scores,and flavor amino acid contents of longissimus dorsi(LD)of growing-finishing pigs(P<0.05).C60 improved meat quality by regulating lipid metabolism and muscle fiber morphology by mediating the expression of genes,L-lactic dehydrogenase(LDH),myosin heavy chain(MyHC)IIa,MyHCIIb,peroxisome proliferator-activated receptor γ(PPARγ),and fatty acid transport protein 1(FATP1)(P<0.05).Moreover,C60 substantially promoted the mRNA expression of antioxidant enzyme genes(P<0.05),which also contributed to improving meat *** findings have important implications for the application of C60 in the livestock industry,especially for improving the meat quality of fattening pigs.

关键词： Zero-dimensional fullerenes Lipid metabolism Meat quality Muscle fiber Antioxidative

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Tuning the Heat Storage Capacity and Storage Dynamics by Macro-Encapsulated Core-Shell Particles with Combined Sensible and Phase Change Storage Properties

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SSRN 2022年

作者： Singer, Matthias Fischlschweiger, Michael Zeiner, Tim Chair of Process Systems Engineering Graz University of Technology Inffeldgasse 25C Graz8010 Austria Chair of Technical Thermodynamics and Energy Efficient Material Treatment Institute of Energy Process Engineering and Fuel Technology Clausthal University of Technology Agricolastraße 4 Clausthal-Zellerfeld38678 Germany

Providing losses optimized and in the dynamics and in the storage capacity tuneable thermal energy storage solutions is a crucial task for the decarbonisation of heat and hence for enabling a circular economy. One important path, therefore, is the development of thermal energy storage modules, which are composed of either sensible or phase change-based heat storage materials. Thereby, the thermal storage capacity and the storage dynamics behaviour are crucial for fulfilling certain application requirements. In this work, a novel macro-encapsulated and spherical heat storage core-shell structure is presented and embedded in a supercritical ammonia working fluid flow field. The core of the macro-capsule is built by an organic low molecular weight substance showing a solid-liquid phase transition in a respective temperature zone, where the shell structure is made of a polymer. Due to the direct coupling of computational fluid dynamics and the simulation of the phase transition of the core material, the influence of the working fluid flow field and shell thickness on the time evolution of temperature, heat transition coefficients and accumulated heat storage is investigated. It is shown, that due to the mixed sensible and phase change storage character, the shell architecture and the working fluid flow field, the heat storage capacity and the storage dynamics can be systematically tuned. © 2022, The Authors. All rights reserved.

关键词： Heat storage

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Confinement Effect and 3d Design Endow Unsaturated Single Ni Atoms with Ultrahigh Stability and Selectivity Towards Co2 Electroreduction

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SSRN 2023年

作者： Ping, Dan Huang, Siguang Wu, Shide Zhang, Yifei Wang, Shiwen Han, Lifeng Tian, Junfeng Guo, Dongjie Qiu, Hua-Jun Fang, Shaoming Henan Provincial Key Laboratory of Surface & Interface Science Henan Engineering Research Center of Chemical Engineering Separation Process Intensification School of Material and Chemical Engineering Zhengzhou University of Light Industry Zhengzhou450002 China School of Materials Science and Engineering Harbin Institute of Technology Shenzhen518055 China

Developing efficient single-atomic catalysts with superior selectivity and outstanding stability for CO2 electroreduction is desperately required. Herein, confinement strategy and three-dimensional (3D) nanoporous structure design strategy are combined to construct unsaturated single Ni sites (Ni-N3) stabilized by pyridinic N-rich interconnected carbon nanosheets. The confinement agent chitosan and its strong interaction with g-C3N4 nanosheet template are effective for dispersing Ni and restraining their agglomeration into Ni nanoparticles during pyrolysis, resulting in ultrastable Ni single-atom catalyst. Due to the confinement effect and structure advantage, such designed Ni-N-CNS exhibits a nearly 100% selectivity and remarkable stability for electrochemical CO2 reduction to CO, exceeding most reported state-of-the-art catalysts. Specifically, the CO Faradaic efficiency (FECO) maintains above 90% over a broad potential range (-0.55 to -0.95 V vs. RHE). Density functional theory calculations explain the high selectivity for CO generation is due to the high energy barrier required for hydrogen evolution on the unsaturated Ni-N3. © 2023, The Authors. All rights reserved.

关键词： Nanosheets

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Study of the Dual Role Mechanism Triggered by In-Situ Cross-Linking in Ultrafiltration Membrane Matrix

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SSRN 2024年

作者： Guan, Wangwang Zhang, Hao She, Jingguo Li, Jiahui Gao, Haifu Song, Ziping Shi, Le Yan, Hongjin Du, Zhiyao Ding, Li Wu, Chunrui Lu, Xiaolong State Key Laboratory of Separation Membranes and Membrane Processes School of Material Science and Engineering Tiangong University Tianjin300387 China Analytical & Testing Center Tiangong University Tianjin300387 China Tianjin Key Laboratory of Green Chemical Technology and Process Engineering School of Chemical Engineering and Technology Tiangong University Tianjin300387 China Cangzhou Institute of Tiangong University Cangzhou061000 China

In this paper, a novel polyvinylidene fluoride (PVDF) hollow fiber ultrafiltration membrane with uniform pore size and hydrophilic cross-linked network in membrane matrix was developed by non‐solvent induced phase separation method. The dual role mechanism of in-situ cross-linking in regulating molecular chain arrangement during phase separation and preventing deterioration of membrane mechanical properties were analyzed. The results demonstrated that the cross-linked network formed by in-situ crosslinking entangled with PVDF molecular chains which improved the regularity of PVDF molecular chains, increasing the uniformity of the pore size distribution, the percentage of the most probable pore size of the modified membrane increased to 93.25%. The cross-linked network was immobilized in the membrane which formed semi-interpenetrating structure, maintaining the mechanical properties of the membrane. The permeation flux of the modified membrane increased by 24.1 times to 477.7 L·m-2·h-1compared to the original PVDF membrane. The rejection of BSA was maintained at 99.4%, with the tensile strength increased to 2.52 MPa. The modified membrane exhibited persistent hydrophilicity in 21 days washing experiment with improved antifouling performance. © 2024, The Authors. All rights reserved.

关键词： Pore size

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Influencing Factors and Identifying Precursors in Phenolic Compounds Formation from Tobacco Extracts Pyrolysis

SSRN

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SSRN 2024年

作者： Lu, Pengfei Wu, Rongcheng Xu, Guangwen Wang, Guoxin School of Materials Science and Engineering Shenyang University of Technology Shenyang110142 China State Key Laboratory of Multi-Phase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing100190 China Key Laboratory on Resources Chemicals and Material of Ministry of Education Shenyang University of Chemical Technology Shenyang110142 China Beijing Biorefine Technology Co. Ltd. Beijing100015 China

Tobacco extracts is one of the important flavors used in tobacco products, however, some toxic phenolic compounds (phenol, o-Cresol, p-Cresol, catechol, and hydroquinone) formed during pyrolysis. In this study, the effects of temperature, heating rate, carrier gas atmosphere, and potassium salts on the formation of phenolic compounds by the pyrolysis of tobacco extracts were investigated quantitatively. The characteristics of phenols formation by five phenol-producing precursors (chlorogenic acid, protein, rutin, glucose, and fructose) were further studied. The results showed that with increasing temperature (300~500 °C), the phenols yields first increased and then decreased, reaching the maximum at about 450 °C. The yields of phenol and catechol can be significantly decreased by air atmosphere, lower heating rate, and addition of potassium acetate. It was further proved that chlorogenic acid, protein, and rutin are important precursors of phenolic compounds and chlorogenic acid had the highest phenol yield of 18178.52 μg/g. Moreover, combined with the content of each precursor in the extracts, it was calculated that 83.6% of the phenol formed at 350 °C came from protein and chlorogenic acid, with chlorogenic acid contributing 41.52%. Adding potassium acetate decreased the generation of phenol and catechol by inhibiting the formation of phenol and catechol by chlorogenic acid, but promoted the formation of cresols by these precursors during the pyrolysis process. © 2024, The Authors. All rights reserved.

关键词： Phenols

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Few-Layer Ni3fe Nanosheets Embedded Porous Nitrogen-Doped Carbon Derived from Asphalt Waste: An Efficient Electrocatalyst for Oxygen Evolution Reaction

SSRN

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SSRN 2024年

作者： Zhao, Wenlong Shangguan, Huangbin Liu, Zhiyi Lin, Jing Huang, Congshu Chen, Hongyi Zhang, Xiaoxiao Wang, Jianzhi Yu, Fa quan Key Laboratory for Green Chemical Process of Ministry of Education Hubei Key Laboratory for Novel Reactor and Green Chemistry Technology Hubei Engineering Research Center for Advanced Fine Chemicals School of Chemical Engineering and Pharmacy Wuhan Institute of Technology Wuhan430073 China National Key Laboratory of Marine Corrosion and Protection Luoyang Ship Material Research Institute Xiamen361101 China

The design and fabrication of stable, high-performance, and affordable oxygen evolution reaction (OER) electrocatalysts is essential for performing practical water electrolysis and generating green hydrogen energy. Here, we report that 2D few layer Ni3Fe nanosheets embedded with 2D porous nitrogen doped carbon (N-NixFe@CF) from asphalt waste and then convolved and assembled into 1D hollow nanotube structures by Lewis acid molten salt etching method, which were used as electrocatalysts for OER. Benefiting from the integrate of 1D hollow nanotube structure and 2D porous nanosheets, the close contact between catalysts and support, and the increased conductivity, the resultant N-Ni3Fe@CF catalysts exhibited high catalytic activities in the OER with low overpotential at a current density of 10 mA cm-2 (114 mV), low Tafel slope (166.6 mV dec-1), and excellent electrochemical stability. This work provides a new concept for expanding the use of asphalt wastes and by-products, as well as a straightforward synthesis method for producing economical, efficient, and long-lasting alkaline OER electrocatalysts. © 2024, The Authors. All rights reserved.

关键词： Nanosheets

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Stimuli responsive co-delivery of celecoxib and BMP2 from micro-scaffold for periodontal disease treatment

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Journal of materials Science & technology 2021年第16期75卷 216-224页

作者： Yi Hao Ran Tian Kaige Lv Zhongning Liu Jing Ni Pingyun Yuan Yongkang Bai Xin Chen Department of Prosthodontics Shanghai Ninth People's Hospital College of StomatologyShanghai Jiao Tong University School of MedicineNational Clinical Research Center of StomatologyShanghai Key Laboratory of Stomatology and Shanghai Research Institute of StomatologyShanghai 200240China Department of Chemical Engineering Shaanxi Key Laboratory of Energy Chemical Process IntensificationInstitute of Polymer Science in Chemical EngineeringSchool of Chemical Engineering and TechnologyXi'an Jiaotong UniversityXi'an710049China Department of Prosthodontics Peking University School and Hospital of StomatologyNational Engineering Laboratory for Digital and Material Technology of StomatologyBeijing Key Laboratory of Digital StomatologyBeijing100081China

Controlling inflammation meanwhile facilitating tissue regeneration has been considered as a promising strategy to treat inflammatory bone defect. Herein, we describe the synthesis of a bio-sensitive poly(lactic-co-glycolic acid)/mesoporous silica nanocarriers core-shell porous microsphere(PLGA/MSNsPMS) encapsulated poly(L-lactic acid)(PLLA) spongy nanofibrous micro-scaffold as a new generation of therapeutic platform for effective reconstruction of bone defects caused by periodontal *** PLGA/MSNs-PMS were designed as stimuli-responsive carriers for on-demand co-delivery of multiple biomolecules to provide proper physiological environment, while the multi-level(from macro-,micro-to nanometers) nanofibrous and porous structures in PLLA micro-scaffold were in charge of the reconstruction of ECM, which synergistically contribute to the enhancement of new tissue formation under inflammatory condition. After local injection into periodontal tissue, this construct could sequentially release bone growth factor(BMP-2) as well as anti-inflammatory drug(celecoxib) loaded MSNs in response to the over-expressed matrix metalloproteinases(MMP) in periodontal region. During alveolar bone regeneration induced by BMP-2 and ECM like structure, the MSNs would further deliver celecoxib in target cells to achieve inflammation inhibition, resulting in effective treatment of periodontal disease.

关键词： periodontal inflammation treatment

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