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Microstructure and strength features of warm and ice-rich frozen soil treated with high-performance cements

Journal of Mountain Science 2019年第6期16卷 1470-1482页

作者： SUN Gao-chen ZHANG Jian-ming dang ying-sheng DING Cong State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 10049China China State Construction Engineering Corporation Aecom Consultant Co. Ltd.Lanzhou 730000China College of Water&Architectural Engineering Shihezi UniversityShihezi 832000China Shanghai Investigation Design&Research Institute Co.Ltd.Shanghai 200434China

Warm and ice-rich frozen soil(WIRFS) exhibits lower shear strength due to the weak binding forces between soil particles and ice crystals. To enhance the strength of WIRFS, frozen soil was treated separately with Portland, Phosphate, Sulphoaluminate, Portland-Phosphate and PortlandSulphoaluminate cements. After the samples were cured under -1.0°C for 7 days, the microscopic pore distribution characteristics and the macro-mechanical properties of WIRFS were investigated using mercury intrusion porosimetry(MIP), scanning electron microscopy(SEM) and unconfined compressive strength(UCS) tests. To quantitatively analyze the laws of pore-size transformation and the variation of Hausdorff volumetric fractal dimensions for pre-and post-treated WIRFS, the CURVEEXTRACT and Image-Pro Plus(IPP) image analysis system has been developed for analysing SEM images of the soil samples. Statistics of the pore-area dimension and pore-volume dimension were calculated. The results reveal that the cement-based treatment of WIRFS can improve the cementation fill of soil pores and the bond forces between soil particles. There is an evident correlation between the microstructure characteristics and the mechanical properties of the treated WIRFS. As the fractal dimensions of pore-area decrease, the unconfined compressive strength of cement-treated WIRFS increases significantly. In contrast, as the fractal dimensions of pore-volume increases, the unconfined compressive strength decreases remarkably.

关键词： Soil stabilizer Frozen soil Microstructure characteristics Macro-mechanical properties Fractal theory Scanning electron microscopy

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Friction and wear properties of N+ ion implanted nylon 1010

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 274-277页

作者： XIONG dang-sheng Department of Materials Science & Engineering Nanjing University of Science and Technology Nanjing 210094 China

The PA1010 was implanted with 450 keV N+ ions to three doses of 5× 1014 cm-2 , 2.5× 1015 cm-2 and 1.25 × 1016 cm-2. The friction and wear behaviors of the ion implanted PA1010 disks rubbing with two ceramic (ZrO2 and Si3N4) balls were studied using a pin-on-disk tribometer under dry friction. The results shows that the wear resistance of PA1010 is increased with the increasing implantation doses. The adhesion, plastic deformation and plow groove are wearing mechanisms for un-implanted PA1010, while abrasive wear for implanted PA1010.

关键词： ion implanted PA1010 tribological properties

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The Riemann Problem for Chaplygin Gas Flow in a Duct with Discontinuous Cross-Section

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Chinese Annals of Mathematics,Series B 2020年第4期41卷 531-546页

作者： Liancheng dang Wancheng sheng Department of Mathematics Shanghai UniversityShanghai 200444China. Corresponding author.Department of Mathematics Shanghai UniversityShanghai 200444China.

The fluid flows in a variable cross-section duct are nonconservative because of the source ***,the Riemann problem and the interactions of the elementary waves for the compressible isentropic gas in a variable cross-section duct were *** this paper,the Riemann problem for Chaplygin gas flow in a duct with discontinuous cross-section is *** elementary waves include rarefaction waves,shock waves,delta waves and stationary waves.

关键词： Duct flow Chaplygin gas equations Nonconservative Riemann problem Delta wave Stationary wave

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Divergent responses of tiller and grain yield to fertilization and fallow precipitation:Insights from a 28-year long-term experiment in a semiarid winter wheat system

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Journal of Integrative Agriculture 2021年第11期20卷 3003-3011页

作者： WANG Rui WANG ying HU Ya-xian dang Ting-hui GUO sheng-li College of Forestry Northwest A&F UniversityYangling 712100P.R.China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYangling 712100P.R.China Institute of Soil and Water Conservation Chinese Academy of Sciences&Ministry of Water ResourcesYangling 712100P.R.China

Tillering is an important phenological stage,which is strongly related to the yield in spike components and final grain yield during winter wheat *** during the fallow season(fallow precipitation)influences tillering in winter wheat on the semi-arid Chinese Loess ***,little work has been done regarding tiller number changes under various types of fertilization and amounts of fallow precipitation on a long-term *** of fallow precipitation and fertilization on tiller were investigated in a winter wheat(Triticum aestivum L.)system in a 28-year field study(1990 to 2017)in a semiarid *** number,spike number and grain yield were measured in four fertilization conditions:control without fertilizer(CK);mineral nitrogen fertilizer alone(N);mineral phosphorus fertilizer alone(P);mineral nitrogen and phosphorus fertilizer together(NP).Based on the long-term annual fallow precipitation,dry years(mean annual fallow precipitation)were *** fertilization alone significantly increased the mean annual tiller number(23%),and the increase in tiller number was higher in wet years(29%)than in the dry years(17%).However,nitrogen fertilization alone had little effect on mean tiller number,while nitrogen and phosphorus together significantly increased mean annual tiller number(30%),mean tiller number in wet years(45%)and mean tiller number in dry years(17%).Tiller number was significantly and positively correlated with fallow precipitation in dry years for all fertilizer treatments,whereas it was weakly and either positively or negatively correlated with fallow precipitation in wet years depending on the *** study found positive correlations between tiller number and fallow precipitation in the CK and NP treatments,and it found negative correlations between tiller number and fallow precipitation in the treatments with nitrogen fertilization alone or phosphorous fertilization alone in wet ***

关键词： tiller grain yield nutrient deficiency fallow precipitation winter wheat

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Predicting ^(28)Si projectile fragmentation cross sections with Bayesian neural network method

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Chinese Physics C 2024年第12期48卷 129-137页

作者： ying-Hua dang Jun-sheng Li Dong-Hai Zhang Institute of Modern Physics Shanxi Normal UniversityTaiyuan 030031China Shanxi University of Electronic Science and Technology Linfen 041000China

This study utilizes the Bayesian neural network(BNN)method in machine learning to learn and predict the cross-sectional data of ^(28)Si projectile fragmentation for different targets at different energies and to quantify the *** detailed modeling process of the BNN is presented,and its prediction results are compared with those of the Cummings,Nilsen,EPAX2,EPAX3,and FRACS models and experimental measurement *** results reveal that,compared with other models,the BNN method achieves the smallest root-mean-square error(RMSE)and the highest agreement with the experimental *** the BNN method and FRACS model show a significant odd-even staggering effect;however,the results of the BNN method are closer to the experimental ***,the BNN method is the only model capable of reproducing data features with low cross-section values at Z=9,and the average ratio of the predicted to experimental values of the BNN is close to *** results indicate that the BNN method can accurately reproduce and predict the fragment production cross sections of ^(28)Si projectile fragmentation and demonstrate its ability to capture key data characteristics.

关键词： Bayesian neural network(BNN) heavy ion collision projectile fragmentation cross section

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Friction and wear properties of ultra-high molecular mass polyethylene reinforced with Al2O3 nano-particle

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 354-358页

作者： FAN Dong-li XIONG dang-sheng Department of Materials Science & Engineering Nanjing University of Science and Technology Nanjing 210094 China Department of Materials Science & Engineering Nanjing University of Science and Technology Nanjing 210094 China

The ultra-high molecular mass polyethylene (UHMMPE) as an artificial joint acetabular material was filled with nano-powder of Al2O3 of various mass fractions. The effect of Al2O3 mass fraction on the hardness, wetting property and tribological properties of the Al2O3-UHMMPE composites under dry friction sliding against both stainless steel and Ti-6Al-4V alloy was investigated. The morphologies of the worn surfaces of composites were observed with optical microscope. The results show that, wetting property and wear resistance of the composites are improved by filling Al2O3, while the friction coefficient is decreased largely under dry friction as compared with that of the unfilled UHMMPE. This is attributed to the reinforcing function of the nano-powder of Al2O3 in the composites. The wear of UHMMPE is dominated by plowing, plastic deformation and fatigue wear; while the Al2O3-UHMMPE composites are characterized by the mild fatigue wear.

关键词： ultra-high molecular mass polyethylene Al2O3 nano-powder filling modification friction and wear properties artificial joint

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Optimal Policies for Quantum Markov Decision Processes

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International Journal of Automation and computing 2021年第3期18卷 410-421页

作者： Ming-sheng ying Yuan Feng sheng-Gang ying Centre for Quantum Software and Information University of Technology SydneyNSW 2007Australia State Key Laboratory of Computer Science Institute of SoftwareChinese Academy of SciencesBeijing 100190China Department of Computer Science and Technology Tsinghua UniversityBeijing 100084China

Markov decision process(MDP)offers a general framework for modelling sequential decision making where outcomes are *** particular,it serves as a mathematical framework for reinforcement *** paper introduces an extension of MDP,namely quantum MDP(q MDP),that can serve as a mathematical model of decision making about quantum *** develop dynamic programming algorithms for policy evaluation and finding optimal policies for q MDPs in the case of *** results obtained in this paper provide some useful mathematical tools for reinforcement learning techniques applied to the quantum world.

关键词： Quantum Markov decision processes quantum machine learning reinforcement learning dynamic programming decision making

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Generalized δ-entropy condition to Riemann solution for Chaplygin gas in traffic flow

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Applied Mathematics and Mechanics(English Edition) 2015年第3期36卷 353-364页

作者： Wancheng sheng ying ZENG Department of Mathematics Shanghai University Department of Mathematics and Physics Quzhou University

The Riemann problem for the Aw-Rascle model in the traffic flow with the Delta initial data for the Chaplygin gas is studied. The solutions are constructed globally under the generalized Rankine-Hugoniot relations, the δ-entropy conditions, and the generalized δ-entropy conditions. A new Delta wave, which is called a primary Delta wave, is defined in some solutions. The primary Delta wave satisfies the generalized Rankine- Hugoniot relations and the generalized δ-entropy conditions. It generates initially from the Delta initial data, which either evaluates a Delta wave, whose weight becomes stronger and stronger, or disappears at a finite time.

关键词： generalized δ-entropy condition Riemann problem for Aw-Rascle model,generalized Rankine-Hugoniot relation Delta initial datum Chaplygin gas

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An effective and green H2O2/H2O/O3 oxidation method for carbon nanotube to reinforce epoxy resin

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Journal of Materials Science & Technology 2020年第5期40卷 24-30页

作者： Qi Wang Wen Shi Bo Zhu dang sheng Su School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China Shenyang National Laboratory for Materials Science Shenyang 110016China Jiangsu Gunuo New Materials Technology Go. Ltd.Yancheng 224051China

Facile green oxidation methods are always desired to functionalize carbon nanotubes(CNTs)in the production of advanced CNT/epoxy *** the present work,an optimized H2O2/H2O/O3 oxidation method was developed,and performances of the H2O2/H2O/O3 oxidized CNT in epoxy matrix were tested and compared with that of the H2O/O3 oxidized CNT and the most commonly used concentrated HNO3 oxidized *** physical and chemical characteristics of the obtained oxidized CNTs were systematically characterized via transmission electron microscopy(TEM),X-ray photoelectron spectroscopy(XPS)and *** performances of the obtained composites were explored by tensile tests,impact tests,dynamic mechanical analysis(DMA)and fracture toughness *** was found that the H2O2/H2O/O3 oxidized CNT exhibited all-around overwhelming advantages over the concentrated HNO3 oxidized CNT on reinforcing the epoxy matrix,while the H2O/O3 oxidized CNT only improved the material *** mechanisms for the different methods oxidized CNTs were studied and *** optimized H2O2/H2O/O3 oxidation method makes scaled production possible,avoids environment pollutions,and holds great potentials to replace the most commonly used concentrated HNO3 oxidation method to oxidize CNT during the preparation of the advanced CNT/epoxy composite.

关键词： Green oxidation method Carbon nanotube Epoxy composite Mechanical properties Interfacial interaction

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Fuzzy Topology Based on Residuated Lattice-Valued Logic

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Acta Mathematica Sinica,English Series 2001年第1期17卷 89-102页

作者： Ming sheng ying State Key Laboratory of Intelligent Technology and Systems Department of Computer Science and Technology Tsinghua University

We use a semantical method of complete residuated lattice-valued logic to give a general- ization of fuzzy topology as a partial answer to a problem by Rosser and Turquette.

关键词： Fuzzy topology Residuated lattice Many-valued logic Semantics

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