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Effect of Ni content on the wear behavior of Al-Si-Cu-Mg-Ni/SiC particles composites

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 374-383页

作者： Yanyu liu Lina jia Wenbo Wang Zuheng Jin Hu Zhang School of Materials Science and Engineering Beihang UniversityBeijing 100191China Ningbo Institute of Technology Beihang UniversityNingbo 315100China Qingdao Research Institute of Beihang University Qingdao 266000China Research Institute for Frontier Science Beihang UniversityBeijing 100191China

In recent years,the addition of Ni has been widely acknowledged to be capable of enhancing the mechanical properties of Al-Si ***,the effect of Ni on the wear behaviors of Al-Si alloys and Al matrix composites,particularly at elevated temperat-ures,remains an understudied *** this study,Al-Si-Cu-Mg-Ni/20wt%SiC particles(SiCp)composites with varying Ni contents were prepared by using a semisolid stir casting *** effect of Ni content on the dry sliding wear behavior of the prepared compos-ites was investigated through sliding tests at 25 and 350℃.Results indicated that theθ-Al_(2)Cu phase gradually diminished and eventually disappeared as the Ni content increased from 0wt%to 3wt%.This change was accompanied by the formation and increase inδ-Al_(3)CuNi andε-Al_(3)Ni phases in *** hardness and ultimate tensile strength of the as-cast composites improved,and the wear rates of the composites decreased from 5.29×10^(−4)to 1.94×10^(−4)mm^(3)/(N∙m)at 25℃and from 20.2×10^(−4)to 7×10^(−4)mm^(3)/(N∙m)at 350℃with the increase in Ni content from 0wt%to 2wt%.The enhancement in performance was due to the presence of strengthening network structures and additional Ni-containing phases in the ***,the wear rate of the 3Ni composite was approximately two times higher than that of the 2Ni composite due to the fracture and debonding of theε-Al_(3)Ni *** wear,delamination wear,and oxidation wear were the predominant wear mechanisms of the investigated composites at 25℃,whereas delamination wear and oxid-ation wear were dominant during sliding at 350℃.

关键词： Al matrix composite microstructure sliding test high temperature wear mechanism

Relationship between hydrogenation degree and pyrolysis performance of jet fuel

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Chinese Journal of Chemical Engineering 2024年第4期68卷 35-42页

作者： Qing liu Tinghao jia Lun Pan Jijun Zou Xiangwen Zhang Key Laboratory for Green Chemical and Technology School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Zhejiang Institute of Tianjin University Ningbo 315201China Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China

Understanding the relationship between the chemical composition and pyrolysis performance of endothermic hydrocarbon fuel(EHF) is of great significance for the design and optimization of advanced EHFs. In this work, the effect of deep hydrogenation on the pyrolysis of commercial RP-3 is *** with different hydrogenation degrees were obtained by the partially and completely catalytic hydrogenation and their pyrolysis performances were investigated using an apparatus equipped with an electrically heated tubular reactor. The results show that with the increase of hydrogenation degree, fuel conversion almost remains constant during the pyrolysis process(500-650°C, 4 MPa);however, the heat sink increases slightly, and the anti-coking performance significantly improves, which are highly related to their H/C ratios. Detailed characterisations reveal that the difference of the pyrolysis performance can be ascribed to the content of aromatics and cycloalkanes: the former are prone to initiate secondary reactions to form coking precursors, while the latter could act as the hydrogen donor and release hydrogen, which will terminate the radical propagation reactions and suppress the coke deposition. This work should provide the guidance for upgrading EHFs by modulating the composition of EHFs.

关键词： RP-3 Fuel Pyrolysis Hydrogenation Deposition

Active MoS_(2)-based electrode for green ammonia synthesis

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Chinese Journal of Chemical Engineering 2024年第1期65卷 268-275页

作者： Xin liu Lei Yang Tao wei Shanping liu Beibei Xiao School of Energy and Power Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Institute Charles Gerhardt Montpellier UMR-5253Universite de MontpellierCNRSENSCMPlace E.Bataillon34095 Montpellier Cedex 05France

Nitrogen electro-reduction under mild conditions is one promising alternative approach of the energyconsuming Haber-Bosch process for the artificial ammonia *** critical aspect to unlocking this technology is to discover the catalysts with high selectivity and *** this work,the N_(2)-to-NH_(3)conversion on the functional MoS_(2)is fully investigated by density functional theory calculations since the layered MoS_(2)provides the ideal platform for the elaborating copies of the nitrogenase found in nature,wherein the functionalization is achieved via basal-adsorption,basal-substitution or edge-substitution of transition metal *** results reveal that the edge-functionalization is a feasible strategy for the activity promotion;however,the basal-adsorption and basal-substitution separately suffer from the electrochemical instability and the NRR ***,MoS_(2)functionalized via edge W-substitution exhibits an exceptional *** energetically favored reaction pathway is through the distal pathway and a limiting potential is less than 0.20 ***,this work escalates the rational design of the high-effective catalysts for nitrogen fixation and provides the explanation why the predicated catalyst have a good performance,paving the guidance for the experiments.

关键词： Nitrogen reduction reaction Density functional theory calculations Molybdenum disulfide Electrochemistry Catalyst Thermodynamics

Weakly Polarized Organic Cation-Modified Hydrated Vanadium Oxides for High-Energy Efficiency Aqueous Zinc-Ion Batteries

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Nano-Micro Letters 2024年第7期16卷 169-186页

作者： Xiaoxiao jia Chaofeng liu Zhi Wang Di Huang Guozhong Cao Department of Materials Science and Engineering University of WashingtonSeattleWA 98195USA School of Materials Science and Engineering Tongji UniversityShanghai 201804People’s Republic of China

Vanadium oxides,par-ticularly hydrated forms like V_(2)O_(5)·nH_(2)O(VOH),stand out as promising cathode candidates for aqueous zinc ion batteries due to their adjustable layered structure,unique electronic characteristics,and high theoretical ***,challenges such as vanadium dissolution,sluggish Zn^(2+)diffusion kinetics,and low operating voltage still hinder their direct *** this study,we present a novel vanadium oxide([C_(6)H_(6)N(CH_(3))_(3)]_(1.08)V_(8)O_(20)·0.06H_(2)O,TMPA-VOH),developed by pre-inserting trimethylphenylammonium(TMPA+)cations into *** incorporation of weakly polarized organic cations capitalizes on both ionic pre-intercalation and molecular pre-intercalation effects,resulting in a phase and morphology transition,an expansion of the interlayer distance,extrusion of weakly bonded interlayer water,and a substantial increase in V^(4+)*** modifications synergistically reduce the electrostatic interactions between Zn^(2+)and the V-O lattice,enhancing structural stability and reaction kinetics during *** a result,TMPA-VOH achieves an elevated open circuit voltage and operation voltage,exhibits a large specific capacity(451 mAh g^(-1)at 0.1 A g^(-1))coupled with high energy efficiency(89%),the significantly-reduced battery polarization,and outstanding rate capability and cycling *** concept introduced in this study holds great promise for the development of high-performance oxide-based energy storage materials.

关键词： Zinc-ion battery Vanadium oxide V_(2)O_(5)·nH_(2)O Pre-intercalation Interlayer engineering

Nanostructured lubricant additives for titanium alloy:Lubrication by the solid-liquid interface with Coulomb repulsion

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Friction 2024年第7期12卷 1564-1579页

作者： Linlin DUAN Dan jia jian LI jianfang liu Haitao DUAN State Key Laboratory of Special Surface Protection Materials and Application Technology Wuhan Research Institute of Materials ProtectionWuhan 430030China Hubei Longzhong Laboratory Xiangyang 441000China College of Life Science and Technology Wuhan Polytechnic UniversityWuhan 430030China

In this work,the advantage of Coulomb repulsion in the intermolecular forces experienced by molecules on the solid–liquid nanosized contact interface is taken,and the superior friction-reducing property of Cu_(3)(PO_(4))2·3H_(2)O(CuP)oil-based additives has been confirmed for titanium ***-dimensional(3D)CuP nanoflowers(CuP-Fs)with a strong capillary absorption effect are prepared to achieve the homogeneous mixing of solid CuP and lubricating *** by CuP-Fs additives for titanium alloy,friction coefficient(COF)can be reduced by 73.68%,and wear rate(WR)reduced by 99.69%.It is demonstrated that the extraordinary friction-reducing property is due to the repulsive solid–liquid interface with low viscous shear force originating from Coulomb repulsion between polar water molecules in CuP and non-polar oil ***,any steric hindrance or connection between this repulsive solid–liquid interface will trigger the adhesion and increase the viscous shear force,for example,dispersant,hydrogen bondings,and shaky adsorbed water ***,the lamellar thickness of CuP and the molecular size of lubricant both have a great influence on tribological *** the lubrication mechanism based on interface Coulomb repulsion is proposed that may help broaden the scope of the exploration in low-friction nanomaterial design and new lubricant systems.

关键词： lubrication nanomaterial additive solid-liquid interface wear

Characteristics of transfer zones under the influence of preexisting faults and regional stress transformation:Wenchang A subsag,Zhujiang River Mouth Basin,northern South China Sea

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Journal of Oceanology and Limnology 2024年第3期42卷 744-759页

作者： wei LI Mingyue CAO Meifang MENG Caiwei FAN Hui LI jia LI Wanqiu WU Ruiqing QIN Xingan LI Yiming liu State Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580China School of Geosciences China University of Petroleum(East China)Qingdao 266580China Zhanjiang Branch China National Offshore Oil Corporation CompanyZhanjiang 524057China

A transfer zone in rift basins preserves important information on regional tectonic evolution and plays significant roles in hydrocarbon *** on the systematic analysis of 3D seismic data and hydrocarbon accumulation conditions,the geometry,kinematics,and reservoir control of a large synthetic overlapping transfer zone in the south of the Wenchang A subsag in the Zhujiang(Pearl)River Mouth basin were *** indicate that the development and evolution of the transfer zone was controlled by the interaction between pre-existing faults and regional stress *** intense rifting of the main faults of the transfer zone controlled the development of source rocks and faultcontrolled slope break *** strike-slip overprint since the Oligocene is conducive to the formation of a large-scale fault-anticline trap,and the secondary faults in the transfer zone contribute to the hydrocarbon *** conjugate intersection area of the NE-and NW-trending faults offers more opportunity for hydrocarbon migration and accumulation.

关键词： transfer zone pre-existing fault regional stress transformation Cenozoic Wenchang A Subsag Zhujiang(Pearl)River Mouth Basin

Impact of Carbon Chain Structures in the Backbone on the Flexibility of Modified Polyarylene Sulfide Resins: Molecular Dynamics Simulations and Mesoscopic Analysis

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Chinese Journal of Polymer Science 2024年第4期42卷 544-557页

作者： Chi Zhang Rong liu Jing-Yuan liu Wen-wei jiang Key Laboratory of Fine Chemical Engineering and Functional Materials School of Chemical EngineeringSichuan UniversityChengdu610065China

In the domain of high-performance engineering polymers, the enhancement of mechanical flexibility in poly(phenylene sulfide) (PPS) resins has long posed a significant challenge. A novel molecular structure, designated as PP-He-IS, wherein imide rings and an aliphatic hexylene chain are covalently incorporated into the PPS backbone to enhance its flexibility, is introduced in this study. Molecular dynamics (MD) simulations are employed to systematically explore the effects of diversifying the backbone chain structures by substituting phenyl units with alkyl chains of varying lengths, referred to as PP-A-IS where “A” signifies the distinct intermediary alkyl chain configurations. Computational analyses reveal a discernable decrement in the glass transition temperature (Tg) and elastic modulus, counterbalanced by an increment in yield strength as the alkyl chain length is extended. Notably, the PP-He-IS variant is shown to exhibit superior yield strength while simultaneously maintaining reduced elastic modulus and Tg values, positioning it as an advantageous candidate for flexible PPS applications. Mesoscopic analyses further indicate that structures such as PP-He-IS, PP-Pe-IS, and PP-Bu-IS manifest remarkable flexibility, attributable to the presence of freely rotatable carbon-carbon single bonds. Experimental validation confirms that a melting temperature of 504 K which is lower than that of conventional PPS, and lower crystallinity are exhibited by PP-He-IS, thereby affording enhanced processability without compromising inherent thermal stability. Novel insights into the strategic modification of PPS for mechanical flexibility are thus furnished by this study, which also accentuates the pivotal role played by molecular dynamics simulations in spearheading high-throughput investigations in polymer material modifications.

关键词： Molecular dynamics simulations Polyarylene Sulfide Main-chain modifications Flexibility Aliphatic hexylene chain

Targeted mutations of BnPAP2 lead to a yellow seed coat in Brassica napus L.

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Journal of Integrative Agriculture 2024年第2期23卷 724-730页

作者： wei Huang Ruyu jiao Hongtao Cheng Shengli Cai jia liu Qiong Hu Lili liu Bao Li Tonghua Wang Mei Li Dawei Zhang Mingli Yan Hunan Research Center of Heterosis Utilization in Rapeseed/Crop Research Institute Hunan Academy of Agricultural SciencesChangsha 410125China Hunan Key Laboratory of Economic Crops Genetic Improvement and Integrated Utilization/School of Life and Health Science Hunan University of Science and TechnologyXiangtan 411201China Key Laboratory of Biology and Genetic Improvement of Oil Crops Ministry of Agriculture and Rural Affairs/Oil Crops Research InstituteChinese Academy of Agricultural SciencesWuhan 430062China

The yellow seed trait is preferred by breeders for its potential to improve the seed quality and commercial value of Brassica *** the present study,we produced yellow seed mutants using a CRISPR/Cas9 system when the two BnPAP2 homologs were knocked *** staining of the seed coat demonstrated that proanthocyanidin accumulation was significantly reduced in the pap2 double mutants and decreased specifically in the endothelial and palisade layer cells of the seed *** and metabolite profiling analysis suggested that disruption of the BnPAP2 genes could reduce the expression of structural and regulated genes in the phenylpropanoid and flavonoid biosynthetic *** broad suppression of these genes might hinder proanthocyanidin accumulation during seed development,and thereby causing the yellow seed trait in *** results indicate that BnPAP2 might play a vital role in the regulatory network controlling proanthocyanidin accumulation.

关键词： yellow seed BnPAP2 proanthocyanidins CRISPR/Cas9

Activation of G-protein-coupled receptor 39 reduces neuropathic pain in a rat model

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Neural Regeneration Research 2024年第3期19卷 687-696页

作者： Longqing Zhang Xi Tan Fanhe Song Danyang Li jiayi Wu Shaojie Gao jia Sun Daiqiang liu Yaqun Zhou wei Mei Department of Anesthesiology Hubei Key Laboratory of Geriatric Anesthesia and Perioperative Brain Healthand Wuhan Clinical Research Center for Geriatric AnesthesiaTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

Activated G-protein-coupled receptor 39(GPR39)has been shown to attenuate inflammation by interacting with sirtuin 1(SIRT1)and peroxisome proliferator-activated receptor-γcoactivator 1α(PGC-1α).However,whether GPR39 attenuates neuropathic pain remains *** this study,we established a Sprague-Dawley rat model of spared nerve injury-induced neuropathic pain and found that GPR39 expression was significantly decreased in neurons and microglia in the spinal dorsal horn compared with sham-operated *** injection of TC-G 1008,a specific agonist of GPR39,significantly alleviated mechanical allodynia in the rats with spared nerve injury,improved spinal cord mitochondrial biogenesis,and alleviated *** changes were abolished by GPR39 small interfering RNA(siRNA),Ex-527(SIRT1 inhibitor),and PGC-1α*** together,these findings show that GPR39 activation ameliorates mechanical allodynia by activating the SIRT1/PGC-1αpathway in rats with spared nerve injury.

关键词： G-protein-coupled receptor 39(GPR39) neuroinflammation neuropathic pain nuclear respiratory factor 1(NRF1) peroxisome proliferator-activated receptor-γcoactivator 1α(PGC-1α) sirtuin 1(SIRT1) spinal cord mitochondrial transcription factor A(TFAM)