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Proof of Two Supercongruences of Truncated Hypergeometric Series_(4)F_(3)

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1015-1028页

作者： guo Shuai MAO Department of Mathematics Nanjing University of Information Science and TechnologyNanjing 210044P.R.China

In this paper,we prove two supercongruences conjectured by Z.-*** via the Wilf-Zeilberger *** of them is,for any prime p>3,4F3[7/6 1/2 1/2 1/2 1/6 1 1]-1/8]-1/2≡p(-2/p)+p^(3)/4(2/p)Ep-3 (mod p^(4))where(·/p)stands f... 详细信息

关键词： Supercongruence truncated hypergeometric series Wilf–Zeilberger method Euler numbers Legendre symbol

Exploring a new path of green and efficient utilization of sinter return fine to produce composite pellets

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Journal of Iron and Steel Research International 2024年第7期31卷 1610-1622页

作者： Yan-biao Chen Wen-guo Liu Hao guo Jing-song Wang Qing-guo Xue Hai-bin Zuo State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China MCC Capital Engineering and Research Incorporation Limited Beijing 100176China

Efficient utilization of sinter return fine is an important measure to reduce cost,increase efficiency,save energy and reduce emission.A new path of green and efficient utilization of return fine was proposed to produce composite *** metallurgical properties of composite pellets under the condition of hydrogen-rich blast furnace were *** experimental results indicate that the coated concentrate was consolidated for the composite pellets through normal Fe_(2)O_(3) *** the surface of core return fine,the liquid phase formed due to its low-melting point,assimilated the adjacent concentrate,and then consolidated with the temperature *** with regular pellets,the com-pressive strength and reduction swelling index of composite pellets were decreased,but the reducibility index and softening-melting properties were *** addition,the reduction degradation index of composite pellets was sig-nificantly higher than that of ***,adding composite pellets was conducive to indirect reduction in blast furnace,reducing fuel ratio and improving production *** to the effect of the roasting system on the metallurgical properties,the roasting temperature and time were determined as 1250℃and 30 min,*** composite pellets can be produced under the traditional pelletizing process.

关键词： Sinter Return fine Composite pellet Roasting system Metallurgical property Hydrogen-rich blast furnace

Underoil superhydrophilic flame-retardant 3D porous composite for efficient on-demand emulsion separation:Interface engineering design on sphagnum moss

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Friction 2024年第10期12卷 2222-2240页

作者： Yuyan guo Peng LIU Wenhao ZHANG Zhiguang guo Weimin LIU Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials Hubei UniversityWuhan 430062China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China

Oil pollution and the energy crisis make oil-water separation an urgent for human *** widespread use of materials with a single emulsion separation capability is *** on-demand separation materials can adapt to a wide range of application scenarios,thus having a wider range of *** underoil superhydrophilic surface is of great significance for realizing the on-demand separation of oil/water emulsions through the removal of water in the oil and oil in the water.A 3D porous emulsion separation material based on the superhydrophilic principle of sphagnum moss was *** material was prepared in a simple step by taking advantage of the adhesion of polydopamine and the introduction of the as-prepared superhydrophilic BaSO4 nanoparticles to achieve superhydrophilicity with a water contact angle(WCA)of 0°and an oil contact angle(OCA)of 157.3°,resulting in excellent separation performance for both water-in-oil and oil-in-water *** superhydrophilic porous composite(OSPC)can complete two kinds of emulsion separations by filtration or *** adsorbs water from water-in-oil emulsion to achieve separation,with a good adsorption capacity of 74.38 g/g and efficiency up to 99%.It can also filter oil-in-water emulsions with an efficiency of 99.92%.The separation efficiencies are all almost unchanged after ten separation ***,the material has excellent flame retardancy,which reduces the possibility of secondary *** three-dimensional porous sponge has excellent on-demand separation performance for multiple *** provides a new preparation strategy for underoil superhydrophilic materials and a new idea for the design direction of special wetting materials for the on-demand separation of oil/water emulsions.

关键词： on-demand emulsion separation porous absorption filtration underoil hydrophilicity superwettability

Light People:*** Mazur speaks about ultrafast optics and education

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Light(Science & Applications) 2024年第3期13卷 402-406页

作者： Chenzi guo Yang Li Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchunChina State Key Laboratory of Precision Measurement Technology and Instrument Department of Precision InstrumentTsinghua UniversityBeijingChina

*** Mazur is a great influencer over and beyond the optics *** a physicist,he is a pioneer of ultrafast optics and was one of the inventors of colliding-pulse mode-locked *** an educator,he not only gave talks to thousands,but also revolutionized teaching with his globally renowned methodology“Peer Instruction”.As a leader and entrepreneur,he co-founded several companies and was President of Optica(formerly the Optical Society)and currently is the Chair of the Optica ***,Light:Science&Applications talked with *** Mazur about his opinions on research,education and *** full interview video can be found in the Supplementary File.

关键词： optics education companies

CMAS-phobic and infiltration-inhibiting protective layer material for thermal barrier coatings

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Journal of Advanced Ceramics 2024年第8期13卷 1254-1267页

作者： Shjun Meng Lei guo Hongbo guo Yuanpeng Wang Hongli Liu School of Materials Science and Engineering Tianjin UniversityTianjin 300072China Tianjin Key Laboratory of Advanced Joining Technology Key Lab of Advanced Ceramics and Machining Technology of Ministry of EducationTianjin300072China School of Materials Science and Engineering Beihang UniversityBeijing 100191China College of Aeronautical Engineering Civil Aviation University of ChinaTianjin 300300China

Calcium-magnesium-alumina-silicate(CMAS)corrosion has attracted special attention in the thermal barrier coating(TBC)*** high temperatures,when CMAS melts,it adheres to the coating surface and penetrates the interior,severely destroying the *** this study,a promising CMAS-phobic and infiltration-inhibiting material,GdPO4,on which molten CMAs is difficult to wet and penetrate,was *** desirable attributes are explained by analyzing the material characteristics of GdPO_(4) and its interfacial reaction with ***4 is demonstrated to have low surface energy,making it difficult for molten CMAS to wet and adhere to the *** in contact with molten CMAS,a double-layer structured reaction layer consisting of an acicular upper sublayer and a compact lower sublayer is formed on the GdPO4 surface,which can effectively impede molten CMAS spreading and ***-principles calculation results revealed that the reaction layer has low surface energy and low adhesion to CMAS,which are favorable for molten CMAS ***,the formation of the reaction layer increases the viscosity of the molten CMAS,which can increase melt wetting and ***,GdPO4,which exhibits excellent CMAS-phobicity and infiltration-inhibiting ability,is a promising protective layer material for TBCs against CMAS adhesion and attack.

关键词： thermal barrier coatings(TBCs) calcium-magnesium-alumina-silicate(CMAS)-phobicity GdPO_(4) interface reaction layer first-principles calculation

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金融因素对期铜价格波动影响的实证研究

中南大学学报（社会科学版） 2015年第2期21卷 124-129页

作者：朱学红冯宇文郭尧琦中南大学商学院湖南长沙410083 中南大学金属资源战略研究院湖南长沙410083 中南大学数学与统计学院湖南长沙410083

采用VEC模型和EGARCH模型实证研究金融因素和沪铜期货价格之间的关系,传导分析结果显示:汇率、外汇储备和货币供给量的变动通过不同的传导方式对期铜价格产生影响,在短期内各变量的变动均会使得期铜价格产生较明显的波动;而从长期来看,... 详细信息

采用VEC模型和EGARCH模型实证研究金融因素和沪铜期货价格之间的关系,传导分析结果显示:汇率、外汇储备和货币供给量的变动通过不同的传导方式对期铜价格产生影响,在短期内各变量的变动均会使得期铜价格产生较明显的波动;而从长期来看,汇率和外汇储备的冲击效果会逐渐消失,但货币供给量的冲击效果具有很长的持续性。根据风险分析结果和信息冲击曲线得出,期铜价格波动的风险主要来源于外汇储备的变动,并且金融因素对期铜价格波动的影响具有明显的非对称性。

关键词：期铜价格汇率外汇储备货币供应量 VEC模型 EGARCH模型

A unified stochastic damage model for concrete based on multi-scale energy dissipation analysis

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Science China(Technological Sciences) 2024年第3期67卷 863-877页

作者： guo ChengGong LI Jie College of Civil Engineering Tongji UniversityShanghai 200092China State Key Laboratory of Disaster Reduction in Civil Engineering Shanghai 200092China

This work proposes a unified damage model for concrete within the framework of stochastic damage mechanics. Based on the micro-meso stochastic fracture model(MMSF), the nonlinear energy dissipation process of the microspring from nanoscale to microscale is investigated. In nanoscale, the rate process theory is adopted to describe the crack growth rate;therefore, the corresponding energy dissipation caused by a representative crack propagation can be obtained. The scale gap from nanoscale to microscale is bridged by a crack hierarchy model. Thus, the total energy dissipated by all cracks from the nanoscale to the microscale is gained. It is found that the fracture strain of the microspring can be derived from the above multi-scale energy dissipation analysis. When energy dissipation is regarded as some microdamage to the microspring, the constitutive law of the microspring is no longer linearly elastic, as previously assumed. By changing the expression of the damage evolution law from fracture strain to energy dissipation threshold, the new damage evolution model is derived. The proposed model can not only replicate the original static model but also extend to cases of rate dependence. By deriving the fracture strain under different strain rates, the rate sensitivity of concrete materials can be reflected. The model parameters can be conveniently obtained by identifying them with experimental data. Finally, several numerical examples are presented to verify the proposed model.

关键词： concrete damage model stochastic damage rate dependent energy dissipation

Localizing vitamin-C through nanoconfinement enables high-rate CO_(2) electrolysis to ethylene

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Science China Materials 2024年第3期67卷 1006-1008页

作者： Zhengyi Qian Shaojun guo School of Materials Science and Engineering Peking UniversityBeijing 100871China

The electrosynthesis of value-added fuels and chemicals from carbon dioxide reduction reaction(CO_(2)RR)is a promising approach for realizing the objectives of carbon neutrality[1].Nevertheless,the current production of desirable multicarbon(C_(2+))chemicals,such as ethylene(C_(2)H_(4)),still encounters challenges related to low selectivity,low current density,and the requirement for high-purity feeding gas[2].

关键词： enable purity dioxide

Facile preparation of coal-based ultramicroporous carbon microspheres for selective CO_(2)capture

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Carbon Resources Conversion 2024年第3期7卷 97-105页

作者： Mei An Tuo guo Qingjie guo Jiangmen Laboratory of Carbon Science and Technology the Hong Kong University of Science and Technology(Guangzhou)JiangmenGuangzhou 529000China State Key Laboratory of High-efficiency Coal Utilization and Green Chemical Engineering School of Chemistry and Chemical EngineeringNingxia UniversityYinchuanNingxia 750021China Key Laboratory of Clean Chemical Engineering in Universities of Shandong College of Chemical EngineeringQingdao University of Science&TechnologyQingdao 266042China

The basic structure of aromatic compounds that are abundant in coal is the carbonaceous precursor derived from carbon ***,it remains to be a huge challenge to prepare carbon microspheres using coal due to the complex construction and composition of ***,a simple and viable way to obtain coal-based microporous carbon microspheres was developed by means of ethanol pyrolysis and a sequential extraction *** as-prepared carbon microsphere featured aspherical micron particles of a uniform size(0.6-1.6㎛),abundant O-functional groups,excellent thermal stability,high SBET(415.5-983.2 m^(2)/g),and plentiful ultra-micropores(63.15-72.72%).The coal-based carbon microsphere exhibited a noteworthy CO_(2)uptake(3.19-4.97 mmol/g at 273 K and 1.0 bar),acceptable CO_(2)/N_(2)selectivity(IAST:23-46)and moderate isosteric heats(20-32 kJ/mol).This synthetic strategy is important for the preparation of ultramicroporous carbon microspheres using coal,and the synthetic carbon microspheres have promising prospects for highly efficient CO_(2)capture.

关键词： Coal Ultramicroporous Carbon microspheres Ethanolysis Sequential extraction CO_(2)capture