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Modelling Effect of Circulation Flow Rate on Inclusion Removal in RH Degasser

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Journal of Iron and Steel Research International 2016年第12期23卷 1243-1248页

作者： shu-guo ZHENG Miao-yong zhu School of Metallurgy Northeastern University

Based on the similarity principles, a 1 ： 7 scale physical model was established to study the behavior of molten steel flow and inclusion removal in a 145 t Rheinsahl-Heraeus （RH） degasser. On the basis of the quantitative measurements of the circulation flow rate and inclusion removal under various lifting gas flow rates, the effect of circulation flow rate on inclusion removal was investigated in the RH degasser. The inclusion removal rate shows the trend of first increase and then decrease twice with increasing the circulation flow rate when the circulation flow rates are smaller than 104.7 L/min. Whereas, the inclusion removal rate increases again with the further increase in circu- lation flow rate when the circulation flow rate is larger than 104.7 L/min. At lower circulation flow rates, inclusions are mainly removed by Stokes flotation to the slag/steel interface after inclusions are transferred near the slag/steel interface by the circulation flow. At higher circulation flow rates, the collision and aggregation of inclusions improves the inclusion removal efficiency. With the further increase in the circulation flow rate, inclusions are mainly removed by following the turbulent fluctuation （turbulent diffusion） to the slag/steel interface after inclusions are transferred near the slag/steel interface by the circulation flow.

关键词： RH degasser lifting gas flow rate circulation flow rate inclusion removal physical modelling

Fretting wear behaviour of high-nitrogen stainless bearing steel under lubrication condition

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Journal of Iron and Steel Research International 2020年第7期27卷 849-866页

作者： Huan Lin Mao-sheng Yang Bai-po shu College of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093YunnanChina Institute for Special Steel Central Iron and Steel Research InstituteBeijing 100081China

The fretting wear performance of high-nitrogen stainless bearing steel(40Cr15Mo2VN)under lubrication conditions was ***-based grease was preparedusing MoS2 and carbon nanotubes(CNTs)as *** 52100 steel ball was used in four-ball test to evaluate the extreme pressure property and wear resistance of *** four-ball test,the grease adding 0.8 mass%MoS2 and 0.8 mass%CNTs,respectively,was chosen and used for fretting *** 52100 ball and 40Cr15Mo2VN steel disc were used as the upper and lower samples for fretting *** results showed that wear power consumption increased with the increase in both sliding velocity and contact *** initial contact stress was 2.047 GPa,the main wear mechanisms were abrasive wear and plastic deformation as the velocity increased 0.028 to 0.112 m/*** the velocity was 0.028 m/s,the main wear mechanisms changed abrasive wear to adhesion wear and finally to abrasive wear and adhesion wear as the initial contact stress increased 1.788 to 2.579 *** volume loss grew sharply becaof the changes in wear *** this condition,the volume loss growth rate can be divided into three regions according to different wear power consumption ranges corresponding to different wear mechanisms.

关键词： High-nitrogen steel Sliding velocity Contact stress Adhesion wear Abrasive wear Wear power consumption

Unconventional Designs for Functional Sodium-Sulfur Batteries

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Energy & Environmental Materials 2023年第4期6卷 405-415页

作者： Jiangfeng Ni Yichen Liu sheng zhu School of Physical Science and Technology Center for Energy Conversion Materials&Physics(CECMP)Jiangsu Key Laboratory of Thin FilmsSoochow UniversitySuzhou 215006China Institute of Molecular Science Key Laboratory of Chemical Biology and Molecular Engineering of Education MinistryShanxi UniversityTaiyuan 030006China

Sodium-sulfur(Na–S)batteries that utilize earth-abundant materials of Na and S have been one of the hottest topics in battery *** low cost and high energy density make them promising candidates for next-generation storage technologies as required in the grid and renewable *** recent years,extensive efforts have been devoted to the diversity and functionalities of Na–S batteries,aiming to extend their potential applications across multiple temporal and spatial ***,we summarize the unconventional designs for the functionalities of Na–S batteries such as flexible batteries,solid-state cells,flame resistance,and operation at extreme *** highlighting these design strategies that help to realize the functionalities,we hope this review offers a pathway to foster the bright future of Na–S batteries in diverse applications.

关键词： flexibility multiple functionalities sodium-sulfur batteries unconventional design

Phase field simulation of single bubble behavior under an electric field

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Chinese Physics B 2018年第9期27卷 389-395页

作者： Chang-sheng zhu Dan Han sheng Xu School of Computer and Communication Lanzhou University of Technology State Key Laboratory of Gansu Advanced Processing and Recycling of Non-Ferrous Metal Lanzhou University of Technology

Based on the Cahn-Hilliard phase field model, a three-dimensional multiple-field coupling model for simulating the motion characteristics of a rising bubble in a liquid is established in a gas-liquid two-phase flow. The gas-liquid interface motion is simulated by using a phase-field method, and the effect of the electric field intensity on bubble dynamics is studied without electric field, or with vertical electric field or horizontal electric field. Through the coupling effect of electric field and flow field, the deformation of a single rising bubble and the formation of wake vortices under the action of gravity and electric field force are studied in detail. The correctness of the results is verified by mass conservation, and the influences of different electric field directions and different voltages on the movement of bubbles in liquid are considered. The results show that the ratio of the length to axis is proportional to the strength of the electric field when the air bubble is stretched into an ellipsoid along the electric field line under the action of electrostatic gravity and surface tension. In addition, the bubble rising speed is affected by the electric field, the vertical electric field accelerates the bubble rise, and the horizontal direction slows it down.

关键词： electro-hydro dynamics numerical simulation phase field method bubble

Automatic modulation classification based on the combination of clustering and neural network

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The Journal of China Universities of Posts and Telecommunications 2011年第4期18卷 13-19,38页

作者： LIUAi-sheng zhu Qi Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and Telecommunications Nanjing 210003 China Key Laboratory on Wideband Wireless Communications and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications Nanjing 210003 China

In this paper, we propose a new modulation classification method based on the combination of clustering and neural network, in which a new algorithm is introduced to extract key features. In order to recognize modulation types based on the constellation diagram such as phase shift keying （PSK） and quadrature amplitude modulation （QAM）, fuzzy C-means （FCM） clustering is adopted for recovering the constellation under different number of clusters. Then cluster validity measure is applied to extract key features which discriminate between different modulation types. The features are sent to neural network so that modulation types can be recognized. In order to conquer the disadvantages of standard back propagation （BP） neural network, conjugate gradient learning algorithm of Polak-Ribiere update is employed to improve the speed of convergence and the performance of modulation recognition. Simulation results show that classification rates of the algorithm proposed in this paper are much higher than those of clustering algorithm.

关键词： modulation classification clustering BP neural network FCM

Θ-type Calderón-Zygmund Operators with Non-doubling Measures

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Acta Mathematicae Applicatae Sinica 2013年第2期29卷 263-280页

作者： Ru-long XIE Li-sheng shu School of Mathematical Sciences University of Science and Technology of China Department of Mathematics Chaohu University Department of Mathematics Anhui Normal University

Let μ be a Radon measure on Rd which may be non-doubling. The only condition that μ must satisfy is μ（B（x,r）） ≤ Urn for all x∈Rd, r 〉 0 and for some fixed 0 〈 n 〈 d. In this paper, under this assumption, we prove that 0-type Calder6n-Zygmund operator which is bounded on L2 （μ） is also bounded from L^∞（μ） into RBMO （μ） and from Hb （μ） into L1（μ）. According to the interpolation theorem introduced by Tolsa, the LP（μ）-boundedness （1 〈 p 〈 ∞） is established for θ-type Calder6n-Zygmund operators. Via a sharp maximal operator, it is shown that commutators and multilinear commutators of θ-type CMderθn-Zygmundoperator with RBMO （μ） function are bounded on LP（μ）（1 〈 p 〈 ∞）.

关键词： non-doubling measure θ-type Calderón-Zygmund operator, commutators multilinear commuta-tors RBMO ( μ ) space H1,∞atb ( μ ) space

Tracing the Deep Carbon Cycle Using Metal Stable Isotopes: Opportunities and Challenges

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Engineering 2019年第3期5卷 448-457页

作者： sheng-Ao Liu shu-Guang Li State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China

The subduction of marine carbonates and carbonated oceanic crust to the Earth’s interior and the return of recycled carbon to the surface via volcanism may play a pivotal role in governing Earth’s atmosphere, climate, and biosphere over geologic time. Identifying recycled marine carbonates and evaluating their fluxes in Earth’s mantle are essential in order to obtain a complete understanding of the global deep carbon cycle (DCC). Here, we review recent advances in tracing the DCC using stable isotopes of divalent metals such as calcium (Ca), magnesium (Mg), and zinc (Zn). The three isotope systematics show great capability as tracers due to appreciable isotope differences between marine carbonate and the terrestrial mantle. Recent studies have observed anomalies of Ca, Mg, and Zn isotopes in basalts worldwide, which have been interpreted as evidence for the recycling of carbonates into the mantle, even into the mantle transition zone (410–660 km). Nevertheless, considerable challenges in determining the DCC remain because other processes can potentially fractionate isotopes in the same direction as expected for carbonate recycling;these processes include partial melting, recycling of carbonated eclogite, separation of metals and carbon, and diffusion. Discriminating between these effects has become a key issue in the study of the DCC and must be considered when interpreting any isotope anomaly of mantle-derived rocks. An ongoing evaluation on the plausibility of potential mechanisms and possible solutions for these challenges is discussed in detail in this work. Based on a comprehensive evaluation, we conclude that the large-scale Mg and Zn isotope anomalies of the Eastern China basalts were produced by recycling of Mg- and Zn-rich carbonates into their mantle source.

关键词： Deep carbon cycle Calcium isotopes Magnesium Zinc

THEORETICALLY AND NUMERICALLY ASSESSING THE VALIDITY OF EULERIAN TRUNCATION IN STOCHASTIC GROUNDWATER MODELING

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Journal of Hydrodynamics 2002年第3期14卷 13-20页

作者： Liao, Hua-sheng Li, shu-Guang Hydraulics Lab.of High Speed Flows Sichuan Univ. Chengdu 610065 China Dept. of Civil and Environ. Eng. Michigan State Univ. East Lansing MI 48824 United States

A theoretical and numerical assessment of the validity of Eulerian truncation in stochastic modeling is presented. Specifically, we analyze and compare theoretically various existing Eulerian-based first-order techniques with and without invoking Eulerian truncation and quantify the terms truncated and retained in the stochastic perturbation equations using high resolution Monte Carlo simulations. We also analyze and compare numerically various existing Eulerian-based first-order techniques and Monte Carlo simulation. The obtained results have demonstrated theoretically and numerically that existing Eulerian-based stochastic perturbation techniques are equivalent. The terms truncated are indeed one order higher than those retained. Therefore, we conclude that Eulerian truncation is mathematically consistent and asymptotic.

关键词： Computer simulation Monte Carlo methods Perturbation techniques Random processes Stochastic programming

Design and Synthesis of Glycosylated Aromatic Nitrogen Mustard Derivatives

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Chemical Research in Chinese Universities 2007年第3期23卷 300-302页

作者： LIU Tie-mei WANG shu-sheng zhu Guang-ze LI Ming-yang ZHANG Li-ping School of Life Sciences Northeast Normal University Changchun 130024 P. R. China China-Japan Union Hospital Jilin Universty Changchun 130033 P. R. China School of Life Science Anhui University Hefei 230039 P. R. China College of Traditional Chingese Medicine in Changchun Changchun 130021 P. R. China

Antibody-directed enzyme prodrug therapy（ADEPT） is a new strategy for the treatment of cancer that has arisen in recent twenty years, the main merits of which are that it can improve the selectivity of anticancer drugs and reduce the side effects in remote tissue. In the present study, two prodrugs-glycosylated aromatic nitrogen mustard derivatives were synthesized. Glucose and lactose were converted into glycosyl donors-trichloroacetimidate; the obtained glycosyl donors were glycosylated with p-nitrophenol （ glycosyl donors） to form β-glucosyl p-nitrobenzene and β-lactosyl p-nitrobenzene that were protected by acetyl in a stereoselective manner; the two products were reduced by zinc dust and then treated with ethylene oxide, afforded two glycosylated nitrogen mustard derivatives that were protected by acetyl; the last step was to deacetylate and then afforded the two target compounds that could be used as prodrugs of ADEPT for further Anti-tumor research.

关键词： Glycosylation Nitrogen mustard derivative Prodrug ADEPT