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Deselenization and detellurization of precious-metal ore concentrates by swelling oxidizing roasting and successive alkaline leaching

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International Journal of Minerals,Metallurgy and Materials 2017年第2期24卷 147-155页

作者： fu-yuan Zhang Ya-jie Zheng Guo-min Peng School of Metallurgy and Environment Central South University Changsha 410083 China Henan Zhongyuan Gold Smelter Co. Ltd. Sanmenxia 472000 China Key Laboratory of Comprehensive Utilization of Gold Resource Sanmenxia 472000 China

A new technique of swelling oxidizing roasting and alkaline leaching was proposed for deselenization and detellurization of pre- cious-metal ore concentrates. Alkali-metal and alkaline-earth-metal chlorides and carbonates were preliminarily selected as swelling agents. The roasting removal rate and alkaline leaching rate of selenium and tellurium were investigated, and NaCl was selected as an appropriate swelling agent. furthermore, the effects of various factors on the selenium gasification rate and leaching rate of selenium and tellurium were investigated. The results show that the selenium gasification rate reaches 88.41% after swelling oxidizing roasting for 2 h at 510~C using an NaC1 dosage coefficient of 100 and a sulfuric acid dosage coefficient of 1.3; the amorphous elemental tellurium is completely transformed into TeO2. The roasted product is subjected to alkaline leaching using a 100 g/L NaOH solution, which results in a selenium leaching rate of 10.51%, a total selenium removal rate of 98.92%, and a tellurium leaching rate of 97.64%. In the alkaline leaching residue, the contents of selenium, tellurium, gold, platinum, and palladium are 0.7825%, 5.492%, 8.333%, 0.2587%, and 1.113%, respectively; the precious metals are enriched approximately sixfold.

关键词： ore treatment precious metals roasting leaching selenium removal tellurium removal

Highly efficient charging and discharging of three-level quantum batteries through shortcuts to adiabaticity

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Frontiers of physics 2022年第3期17卷 101-109页

作者： fu-Quan Dou yuan-Jin Wang Jian-An Sun College of Physics and Electronic Engineering Northwest Normal UniversityLanzhou 730070China

Quantum batteries are energy storage devices that satisfy quantum mechanical *** to improve the battery’s performance such as stored energy and power is a crucial element in the quantum ***,we investigate the charging and discharging dynamics of a three-level counterdiabatic stimulated Raman adiabatic passage quantum battery via shortcuts to adiabaticity,which can compensate for undesired transitions to realize a fast adiabatic evolution through the application of an additional control field to an initial *** scheme can significantly speed up the charging and discharging processes of a three-level quantum battery and obtain more stored energy and higher power compared with the original stimulated Raman adiabatic *** explore the effect of both the amplitude and the delay time of driving fields on the performances of the quantum *** experimental implementation in superconducting circuit and nitrogen–vacancy center is also discussed.

关键词： quantum battery charging and discharging dynamics shortcuts to adiabaticity

Laboratory-scale column study for remediation of TCE-contaminated aquifers using three-section controlled-release potassium permanganate barriers

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Journal of Environmental Sciences 2013年第5期25卷 971-977页

作者： Baoling yuan Fei Li Yanmei Chen Ming-Lai fu Institute of Municipal and Environmental Engineering College of Civil EngineeringHuaqiao University College of Civil Engineering Fuzhou University Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of Sciences

A laboratory-scale study with a sand column was designed to simulate trichloroethylene（TCE） pollution in the aquifer environment with three-section controlled-release potassium permanganate（CRP） *** main objective of this study was to evaluate the feasibility of CRP barriers in remediation of TCE in aquifers in a long-term and controlled *** particles with a 1：3 molar ratio of KMnO 4 to stearic acid showed the best controlled-release properties in pure water,and the theoretical release time was 138.5 *** results of TCE removal in the test column indicated that complete removal efficiency of TCE in a sand column by three-section CRP barriers could be reached within 15 *** molar ratio of KMnO 4 to TCE in the three-section CRP barriers was 16：1,which was much lower than 82：1 as required when KMnO 4 solution is used directly to achieve complete destruction of *** result revealed that the efficiency of CRP for remediation of TCE was highly improved after encapsulation.

关键词： chlorinated solvent encapsulation groundwater KMnO 4 permeable reactive barrier sand column

Microstructure and Mechanical Properties of CNT-Reinforced AZ91D Composites Fabricated by Ultrasonic Processing

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Acta Metallurgica Sinica(English Letters) 2016年第7期29卷 652-660页

作者： fu-Ze Zhao Xiao-Hui Feng yuan-Sheng Yang Institute of Metal Research Chinese Academy of Sciences

Carbon nanotube （CNT）-reinforced AZ91D alloy composite was fabricated by ultrasonic processing. The microstructure and mechanical properties of the CNTs/AZ91D composites were investigated. Obvious grain refinement was achieved with the addition of 0.5 wt% CNTs. The SEM observation indicated that CNTs were distributed near the grain boundary or around the inter-grain β-Mg17A112 phase. No evident reaction product was found at the interface between CNTs and AZ91D matrix. Compared to the monolithic AZ91D alloy, the yield strength, ultimate tensile strength, and elongation of the 0.5 wt% CNTs/AZ91D composite were improved significantly. However, the poor interface bonding between CNTs and AZ91D matrix restricted further improvement in mechanical properties.

关键词： Carbon nanotubes (CNTs) Magnesium matrix composites Ultrasonic vibration Microstructure Mechanical properties

Multi-Behavior fusion Based Potential Field Method for Path Planning of Unmanned Surface Vessel

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China Ocean Engineering 2019年第5期33卷 583-592页

作者： fu Ming-yu WANG Sha-sha WANG yuan-hui College of Automation Harbin Engineering University

The problem of the unmanned surface vessel (USV) path planning in static and dynamic obstacle environments is addressed in this paper. Multi-behavior fusion based potential field method is proposed, which contains three behaviors: goal-seeking, boundary-memory following and dynamic-obstacle avoidance. Then, different activation conditions are designed to determine the current behavior. Meanwhile, information on the positions, velocities and the equation of motion for obstacles are detected and calculated by sensor data. Besides, memory information is introduced into the boundary following behavior to enhance cognition capability for the obstacles, and avoid local minima problem caused by the potential field method. Finally, the results of theoretical analysis and simulation show that the collision-free path can be generated for USV within different obstacle environments, and further validated the performance and effectiveness of the presented strategy.

关键词： USV path planning potential field method multi-behavior fusion activation conditions local minima

Texture Evolution of Columnar Grains in Electrical Steel During Hot Rolling

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Journal of Iron and Steel Research International 2013年第10期20卷 99-106页

作者： SHAO yuan-yuan YANG Ping fu Yong-jun MAO Wei-min School of Materials Science and Engineering University of Science and Technology Beijing Cold Rolling Silicon Steel Division Angang Steel Company Limited

Columnar grains in cast slabs of electrical steel show strong anisotropy in grain orientation and morphology and thus influence the subsequent microstructure and texture after hot rolling significantly. The texture evolution of hot rolled sheets containing initial columnar grains with their 〈100〉 directions approximately parallel to the rolling direction （RD）, transverse direction （TD） and normal direction （ND） of the hot rolled sheets was investigated by using EBSD technique. The results indicated that, whatever the initial texture of the columnar grains was, typical Goss, brass-type and copper-type shear texture component could develop in shear-deformed surface region. The copper-type texture formed under the maximum shearing force with the fine, sheared or dynamically recrystallized grains, and Goss grains were mainly elongated and deformed grains, while brass grains behaved between them. Ad- ditionally, the rotating relationship of the three types of shear textures was different due to the restriction of grain boundaries. In homogenously deformed center region, the RD sample contained more {112}〈110^-〉 grains, and TD sample was covered by {100} textures such as {100}〈011〉 and {100}〈021〉 with coarse grains, while the ND sample developed many {100}〈001〉 grains which were attributed to more {100} grains in the initial sample. Re- markable texture transition occurred on both sides of grain boundaries when {110} grains were adjacent to mfiber texture grains. It was found that significant texture gradient and preferred distribution of rotating axis existed in the soft orientation grains on the α- fiber when the grains neighbored hard grains on γ-fiber.

关键词： electrical steel columnar grain hot rolling texture orientation

Defect engineering for high-selection-performance of N_(2) activation over CeO_(2)(111) surface

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Chinese Chemical Letters 2022年第4期33卷 2188-2194页

作者： Fang yuan Risheng Sun Ling fu Guozheng Zhao Key Laboratory of Magnetic Molecules and Magnetic Information Materials Ministry of Education The School of Chemistry and Material ScienceShanxi Normal UniversityLinfen 041004China Institute of Environment and Energy Catalysis Shaanxi Key Laboratory of Optoelectronic Functional Materials and DevicesSchool of Materials Science and Chemical EngineeringXi'an Technological UniversityXi'an 710021China

Nitrogen reduction reactions(NRR) under room conditions remain the challenge for N_(2)activation on metal-based catalysis materials. Herein, the M-doped CeO_(2)(111)(M = Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn) with oxygen vacancies, are systematically investigated by spin-polarized DFT + U *** discuss briefly the situation of OVs on pure and reduced cerium, and we found that(1) doping TMs can promote the formation of oxygen defects, apart from Ti and V-dopant,(2) the O atoms are easier to escape connecting to M atoms than the ones of adjacent atoms connecting to the Ce(111), the value of OVs formation energies decrease as the TMs radius decrease. Also, our computational results show that Cr-doped, Mn-doped, Fe-doped, and Co-doped CeO_(2)(111) adsorbs N;strongly than the stoichiometric surface and other M-doped CeO_(2)surfaces with adsorption energies of-0.82,-1.02,-0.83 and-1.05 e *** COHP analysis, it is found that the predicted active sites have good catalytic performance.

关键词： Nitrogen reduction CeO_(2)(111) Defect Mechanism

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32例皮肤黑色素瘤临床特点分析

中国麻风皮肤病杂志 2025年第1期41卷 29-32页

作者：宋志华江渊付学锋浙江大学医学院附属金华医院皮肤科浙江金华321000

回顾性分析2017年1月至2024年5月我院皮肤科32例皮肤黑色素瘤患者的临床资料。结果示男性发病率为女性的1.46倍;平均发病年龄(69.13±15.95)岁,中位发病年龄为66岁;所有患者均行前哨淋巴结活检,4例淋巴结转移均发生于瘤体>3 cm的患者;SO... 详细信息

回顾性分析2017年1月至2024年5月我院皮肤科32例皮肤黑色素瘤患者的临床资料。结果示男性发病率为女性的1.46倍;平均发病年龄(69.13±15.95)岁,中位发病年龄为66岁;所有患者均行前哨淋巴结活检,4例淋巴结转移均发生于瘤体>3 cm的患者;SOX10、S-100蛋白、Melan A、HMB45表达阳性率均大于90%;Ki67、Cyclin D1阳性率分别为87.50%、78.13%;Ki67表达水平>5%占比87.50%。

关键词：黑色素瘤病理免疫组化临床特点

THE DYNAMICAL BEHAVIOR OF NON-SMOOTH SYSTEM WITH IMPULSIVE CONTROL STRATEGIES

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International Journal of Biomathematics 2012年第3期5卷 297-313页

作者： yuan-shun TAN JU-HUA LIANG SAN-YI TANG Department of Mathematics and Physics Chongqing Jiaotong University Chongqing 400074 P. R. China College of Mathematics and Information Science Shaanxi Normal University Xi'an 710062 P. R. China

Non-smooth system including impulsive strategies at both fixed and unfixed times are analyzed. For the model with fixed impulsive effects, the global stability of pest eradi- cation periodic solution and the dominance of dynamic behavior are investigated. This indicates that the model with fixed moments has the potential to protect the natural enemies from extinction, but under some conditions may also serve to extinction of the pest. The second model is constructed according to the practices of IPM, that is, when the pest population reaches the economic injury level, a combination of biological, cultural, and chemical tactics that reduce pests to tolerable levels is used. Numerical investigations imply that there are several different types of periodic solutions and their maximum amplitudes are always less than the given economic threshold. The results also show that the time series at which the IPM strategies are applied are quite complex, which means that the application and realization of IPM in practice are very difficult.

关键词： Dominance non-smooth system impulsive control strategies integrated pest management global stability.