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Preparation and Microsco.ic Characterization of Asphalt Modified by Ethylene Metal-free Phthalocyanine-dispersed Graphene

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Journal of Wuhan University of Technology(Materials Science) 2022年第1期37卷 66-75页

作者： HUANG Gang HUANG Hao ZHANG Xia HE Junxi ZHOU Chao TAN Yan FENG Manman LÜChuncheng National and Local Joint Engineering Laboratory of Traffic Civil Engineering Materials Chongqing Jiaotong UniversityChongqing 400074China Xinjiang Transportation Planning SurveyDesign and Research Institute Co.LtdWulumuqi 830006China China Merchants chongqing Testing Center for Highway Engineering co. LtdChongqing 400074China

Graphene-modified asphalt(GMA)for road application was prepared via using metal-free phthalocyanine-dispersed to modify an SK-70#base asphalt with *** preparation parameters are as follows:the co.tent of graphene is 0.26%based on the mass percentage of absolute ethanol,the co.tent of nonmetal phthalocyanine is 190%based on the mass percentage of graphene,and then the GMA is prepared via unique high-speed shearing with co.tinuing to ventilate nitrogen,which can prevent the aging of modified asphalt in the high-speed shearing process,and effectively evaluate the *** penetration,softening point,force ductility,and fracture energy of GMA were significantly improved based on the base ***,the inco.poration of graphene co.ld enhance the base asphalt’s high-and low-temperature *** modification mechanism was researched via metallographic microsco.y,co.puted tomography(CT),Fourier transform infrared spectrosco.y(FTIR),and atomic force microsco.y(AFM).Adsorption and physical dispersion of the asphaltenes and resins in the phthalocyanine-graphene system were co.firmed.

关键词： ethylene metal-free phthalocyanine GMA performance dispersion and adsorption asphaltene resin

Self-Supervised Graph Neural Networks for Accurate Prediction of Néel Temperature

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Chinese Physics Letters 2022年第6期39卷 5-11页

作者： Jian-Gang Kong Qing-Xu Li Jian Li Yu Liu Jia-Ji Zhu School of Science Chongqing University of Posts and TelecommunicationsChongqing 400065China Institute for Advanced Sciences Chongqing University of Posts and TelecommunicationsChongqing 400065China Southwest Center for Theoretical Physics Chongqing UniversityChongqing 401331China Inspur Electronic Information Industry co. LtdBeijing 100085China

Antiferromagnetic materials are exciting quantum materials with rich physics and great potential for *** the other hand, an accurate and efficient theoretical method is highly demanded for determining critical transition temperatures, Néel temperatures, of antiferromagnetic materials. The powerful graph neural networks(GNNs) that succeed in predicting material properties lose their advantage in predicting magnetic properties due to the small dataset of magnetic materials, while co.ventional machine learning models heavily depend on the quality of material descriptors. We propose a new strategy to extract high-level material representations by utilizing self-supervised training of GNNs on large-scale unlabeled datasets. Acco.ding to the dimensional reduction analysis, we find that the learned knowledge about elements and magnetism transfers to the generated atomic vector representations. co.pared with popular manually co.structed descriptors and crystal graph co.volutional neural networks, self-supervised material representations can help us to obtain a more accurate and efficient model for Néel temperatures, and the trained model can successfully predict high Néel temperature antiferromagnetic materials. Our self-supervised GNN may serve as a universal pre-training framework for various material properties.

关键词： utilizing networks neural

Experimental investigation of spectral evolution in flash radiation by hypervelocity impact on aluminum plates

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Defence Technology（防务技术） 2024年第7期37卷 96-110页

作者： Xing Chen Yonggang Lu Zhiwen Li Zhonghua Cui Institute of Systems Engineering China Academy of Engineering PhysicsMianyang 621900SichuanChina chongqing Qianwei Technology Group co. LtdChongqing 401121China

In this study,a series of hypervelocity impact tests were carried out based on a two-stage light gas gun,and the sequence spectrum and radiation evolution data of the impact products under different impact co.ditions were *** diameter of the projectile is 3-5 mm,the impact velocity is 3.13-6.58 km/s,and the chamber pressure is 0.56-990 *** spectrum of ejected debris cloud in the 250-310 nm band were obtained using a transient spectral measurement system and a multi-channel radiometer measurement *** test results reveal that the flash radiation intensity increases as a power function with the kinetic energy of the ***,the peak value of the line spectrum decreases as the chamber vacuum degree increases,while the radiation width gradually *** line spectrum in the spectral characterization curve co.responds to the ejected debris clouds splitting phase,which does not produce significant line spectrum during material fragmentation and is dominated by the co.tinuum spectrum produced by blackbody *** will appear one or three characteristic peaks in the flash radiation time curve,the first and seco.d peaks co.respond to the penetration phase and the third peak co.responds to the expansion phase of the ejected debris clouds on the time scale,the first and seco.d peaks are more sensitive to the chamber vacuum degree,and when the pressure is higher than 99 Pa,the first and seco.d characteristic peaks will *** radiant heat attenuation of the flash under different impact co.ditions is significantly different,the attenuation exponent has a power function relationship with the impact velocity and the chamber vacuum degree,while the attenuation exponent has a linear relationship with the diameter of the projectile,the specific expression of the attenuation exponent is obtained by *** findings from this research can serve as a valuable reference for remote diagnostic technologies based on flash radiation characte

关键词： Hypervelocity impact Flash radiation Evolution Spectral characteristics Damage evaluation

Generalized stress field in granular soils heap with RayleigheRitz method

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第1期9卷 135-149页

作者： Gang Bi CH2M Inc. Englewood USA chongqing Titan Architects-Multi-Disciplinary Practice co. Chongqing China

The stress field in granular soils heap(including piled co.l) will have a non-negligible impact on the settlement of the underlying soils. It is usually obtained by measurements and numerical *** the former method is not reliable as pressure cells instrumented on the interface between piled co.l and the underlying soft soil do not work well, results from numerical methods alone are necessary to be doubly checked with one more method before they are extended to more co.plex cases. The generalized stress field in granular soils heap is analyzed with Rayleighe Ritz method. The problem is divided into two cases: case A without horizontal co.straint on the base and case B with horizontal co.straint on the base. In both cases, the displacement functions u(x, y) and v(x, y) are assumed to be cubic polynomials with 12 undetermined parameters, which will satisfy the Cauchy’s partial differential equations, generalized Hooke’s law and boundary equations. A function is built with the Rayleighe Ritz method acco.ding to the principle of minimum potential energy, and the problem is co.verted into solving two undetermined parameters through the variation of the function, while the other parameters are expressed in terms of these two parameters. By co.parison of results from the Rayleighe Ritz method and numerical simulations, it is demonstrated that the Rayleighe Ritz method is feasible to study the generalized stress field in granular soils heap. Solutions from numerical methods are verified before being extended to more co.plicated cases.

关键词： Generalized stress field Rayleighe Ritz method Stress depression Variation of the function Principle of minimum potential energy

Mechanical performance and texture characteristic of an IF steel co.taining Nb and Ti by double co.d rolling

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International Journal of Minerals,Metallurgy and Materials 2009年第1期16卷 51-57页

作者： Ling-yun Wang Peng Zhang Wei Li Guang-jie Huang co.lege of Materials Science and Engineering Chongqing University Chongqing 400030 China Technology Institute of Sichuan Chuanwei Group co. Ltd. Weiyuan 642400 China

Single co.d rolling and double co.d rolling were applied to hot rolled strips with different reduction ratios. The evolutions of { 100}, { 111} and Goss face texture during double rolling were investigated by co.paring the orientation distribution function （ODF） of the double rolled sample with that of the single rolled one. The double co.d rolling texture is characterized by a higher γ-texture and a lower α-texture, and the { 111}〈112〉 co.ponent is improved remarkably. Based on the TEM observation and mechanical properties test, it is found that the reduction ratio assignment significantly affects the texture variation, as-annealing microstructures, and properties of the double co.d rolled samples. These results may provide a theoretical guide for the industrial production of double co.d rolled IF steel.

关键词： IF steel co.d rolling double co.d rolling texture mechanical properties

Numerical simulation of the blast wave of a multilayer co.posite charge

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Defence Technology（防务技术） 2020年第1期16卷 96-106页

作者： Xiao-wen Hong Wei-bing Li Wei Cheng Wen-bin Li He-yang Xu ZNDY of Ministerial Key Laboratory Nanjing University of Science and TechnologyNanjingPR China chongqing Hongyu Precision Industrial co. LtdChongqingPR China

The numerical simulation of a blast wave of a multilayer co.posite charge is investigated.A calculation model of the near-field explosion and far-field propagation of the shock wave of a co.posite charge is established using the AUTODYN finite element *** of the near-field and far-field calculations of the shock wave respectively co.verge at cell sizes of 0.25-0.5 cm and 1-3 *** Euler--fluxco.rected transport solver is found to be suitable for the far-field calculation after mapping.A numerical simulation is co.ducted to study the formation,propagation,and interaction of the shock wave of the co.posite charge for different initiation *** is found that the initiation mode obviously affects the shock-wave waveform and pressure distribution of the co.posite ***,it is found that the area of the overpressure distribution is greatest for internal and external simultaneous initiation,and the peak pressure of the shock wave exponentially decays,fitting the calculation formula of the peak overpressure attenuation under different initiation modes,which is obtained and verified by *** difference between numerical and experimental results is less than 10%,and the peak overpressure of both internal and external initiation is 56.12% higher than that of central single-point initiation.

关键词： Structure of co.posite charge Initiation mode Blast wave Cell size in calculation Numerical simulation

Laminar Flame Instability of n-Hexane,n-Octane,and n-Decane in Spherical Expanding Flames

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Journal of Thermal Science 2024年第3期33卷 1189-1199页

作者： YIN Geyuan HU Erjiang LI Xiaotian LV Xin HUANG Zuohua State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an710049China United Automotive Electronic Systems co. LtdShanghai201206China chongqing Changan Automobile co. Ltd.Chongqing401120China

This paper focuses on the laminar flame instability of three high molecular weight n-alkanes,namely n-hexane,n-octane,and *** experiment was carried out in a co.stant volume co.bustion bomb to get the flame *** critical radius under different co.ditions was extracted using the image processing *** with the existing critical Peclet number theory,the dominant factors of flame instability under current co.ditions for three n-alkanes can be figured ***,the average cell size(equivalent cell radius,R_(cell))was extracted to provide quantitative analysis of the flame cellular structure,based on the method developed in this *** theoretical R_(cell)were also calculated and co.pared with the experimental results to validate the proposed method.

关键词： cellular instability equivalent cell radius critical Peclet number spherical flame

Time-resolved fluoroimmunoassay for quantitative determination of tylosin and tilmico.in in edible animal tissues

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Chinese Science Bulletin 2013年第15期58卷 1838-1842页

作者： WEI Shu LE Tao CHEN Yong XU Jian HE HongQiu NIU XiaoDong LUO JinHua co.lege of Life Science Chongqing Normal University chongqing Academy of Science and Technology chongqing RuoFeng Bio-Tech co. Ltd

To quantitatively determine tylosin and tilmico.in in edible animal tissues,a time-resolved fluoroimmunoassay(TRFIA) has been developed and *** this purpose,desmyco.in-O-carboxymethoxylamine-BSA was fixed onto microtiter plates,standards and samples were loaded and,finally,diluted europium-labeled anti-tylosin antibodies were *** show that the limit of detection for tylosin was 0.03 ng mL-1 and that for tilmico.in was 0.05 ng *** reco.eries were 73.6% to 120.5%,with co.fficients of variation below 15.6% in various biological matrices spiked with tylosin and tilmico.in at co.centrations of 50-200 *** was good co.relation(R2>0.99) between the TRFIA,an enzyme-linked immunosorbent assay and high performance liquid chromatography *** co.clusion,the new TRFIA is applicable to the detection of tylosin and tilmico.in and is an effective and eco.omical method that will enable high-throughput sample *** method is expected to be widely applicable.

关键词：时间分辨荧光泰乐菌素替米考星动物组织定量测定荧光免疫食用生物样品

Enhancing hydrogen storage performance via optimizing Y and Ni element in magnesium alloy

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Journal of Magnesium and Alloys 2022年第3期10卷 888-903页

作者： Xu Pang Lei Ran Yu'an Chen Yuxiao Luo Fusheng Pan co.lege of materials Science and engineering Chongqing UniversityChongqing 400044China National Engineering Research for magnesium Alloys Chongqing UniversityChongqing 400044China Guangdong Guoyan Science and Technology Research Center co. LtdGuangdong 518000China

Magnesium-based hydrogen storage materials are co.sidered as one of the most promising candidates for solid state hydrogen storage due to their advantages of high hydrogen capacity,excellent reversibility and low *** this paper,Mg_(91.4)Ni_(7)Y_(1.6) and Mg_(92.8)Ni_(2.4)Y_(4.8) alloys were prepared by melting and ball *** microstructures and phases were characterized by X-ray diffraction,scanning electron microsco.e and transmission electron microsco.e,and hydrogen absorbing and desorbing properties were tested by the high pressure gas adsorption apparatus and differential scanning calorimetry(DSC).In order to estimate the activation energy and growth mechanism of alloy hydride,the JMAK,Arrhenius and Kissinger methods were applied for *** hydrogen absorption co.tent of Mg_(92.8)Ni_(2.4)Y_(4.8) alloy reaches 3.84 wt.%within 5 min under 350℃,3 MPa,and the maximum hydrogen capacity of the alloy is 4.89 wt.%in same ***,the hydrogen absorption of Mg_(91.4)Ni_(7)Y_(1.6) alloy reaches 5.78 wt.%within 5 min,and the maximum hydrogen absorption of the alloy is 6.44 wt.%at 350℃and 3 *** hydrogenation activation energy of Mg_(94.4)Ni_(7)Y_(1.6) alloy is 25.4 kJ/mol H_(2),and the enthalpy and entropy of hydrogen absorption are-60.6 kJ/mol H_(2) and 105.5 J/K/mol H_(2),*** alloy begins to dehydrogenate at 210℃,with the dehydrogenation activation energy of 87.7 kJ/mol H_(2).By altering the addition amount of Ni and Y elements,the 14 H-LPSO phase with smaller size and ternary eutectic areas with high volume fraction are obtained,which provides more phase boundaries and catalysts with better dispersion,and there are a lot of fine particles in the alloy,these structures are beneficial to enhance the hydrogen storage performance of the alloys.

关键词： Hydrogen storage materials LPSO phase Catalytic effect Hydrogen storage performance