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期刊论文 29

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MnAl 1

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分布式优化;高性能算法;多智能体系统;机器学习问题;随机梯度 1

分布式计算机控制系统 1

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Bioleaching of copper from pre and post thermally activated low grade chalcopyrite contained ball millspillage

Sandeep PANDA, Nilotpala PRADHAN, Umaballav MOHAPATRA, Sandeep K. PANDA, Swagat S. RATH, Danda S. RAO, Bansi D. NAYAK, Lala B. SUKLA, Barada K. MISHRA

《环境科学与工程前沿(英文)》 2013年 第7卷 第2期   页码 281-293 doi: 10.1007/s11783-013-0484-5

摘要: Bioleaching of a low grade chalcopyrite (ball mill spillage material) was tested for copper recovery in shake flasks. The original samples (as received) were thermally activated (600°C, 30 min) to notice the change in physico-chemical and mineralogical characteristics of the host rock and subsequently its effect on copper recovery. A mixed culture of acidophilic chemolithotrophic bacterial consortium predominantly entailing strain was used for bioleaching studies and optimization of process parameters of both original and thermally activated samples. Mineralogical characterization studies indicated the presence of chalcopyrite, pyrite in the silicate matrix of the granitic rock. Field emission scanning electron microscopy coupled with Energy dispersive spectroscopy (FESEM-EDS) and X-ray Fluorescence (XRF) analysis indicated mostly SiO . With pH 2, pulp density 10% w/v, inoculum 10% v/v, temperature 30°C, 150 r·min , 49% copper could be recovered in 30 days from the finest particle size (-1+ 0.75 mm) of the original spillage sample. Under similar conditions 95% copper could be recovered from the thermally activated sample with the same size fraction in 10 days. The study revealed that thermal activation leads to volume expansion in the rock with the development of cracks, micro and macro pores on its surface, thereby enabling bacterial solution to penetrate more easily into the body, facilitating enhanced copper dissolution.

关键词: ball mill spillage     thermal activation     bioleaching     copper    

Advantageous mechanochemical synthesis of copper(I) selenide semiconductor, characterization, and properties

《化学科学与工程前沿(英文)》 2022年 第16卷 第3期   页码 433-442 doi: 10.1007/s11705-021-2066-6

摘要: Copper(I) selenide-nanocrystalline semiconductor was synthesized via one-step mechanochemical synthesis after 5 min milling in a planetary ball mill. The kinetics of synthesis was followed by X-ray powder diffraction analysis and specific surface area measurements of milled 2Cu/Se mixtures. The X-ray diffraction confirmed the orthorhombic crystal structure of Cu2Se with the crystallite size ~25 nm. The surface chemical structure was studied by X-ray photoelectron spectroscopy, whereby the binding energy of the Cu 2p and Se 3d signals corresponded to Cu+ and Se2– oxidation states. Transmission electron microscopy revealed agglomerated nanocrystals and confirmed their orthorhombic structure, as well. The optical properties were studied utilizing ultraviolet-visible spectroscopy and photoluminescence spectroscopy. The direct bandgap energy 3.7 eV indicated a blue-shift phenomenon due to the quantum size effect. This type of Cu2Se synthesis can be easily adapted to production dimensions using an industrial vibratory mill. The advantages of mechanochemical synthesis represent the potential for inexpensive, environmentally-friendly, and waste-free manufacturing of Cu2Se.

关键词: Cu2Se     berzelianite     nanocrystalline semiconductor     mechanochemical synthesis     planetary ball mill    

characterization of nanocrystalline ZrO2-7%Y2O3 powders for thermal barrier coatings by high-energy ball

Kirsten BOBZIN, Lidong ZHAO, Thomas SCHLAEFER, Thomas WARDA

《机械工程前沿(英文)》 2011年 第6卷 第2期   页码 176-181 doi: 10.1007/s11465-011-0220-4

摘要:

High-energy ball milling is an effective method to produce nanocrystalline oxides. In this study, a conventional ZrO2-7%Y2O3spray powder was ball-milled to produce nanocrystalline powders with high levels of crystalline disorders for deposition of thermal barrier coatings. The powder was milled both with 100Cr6 steel balls and with ZrO2-3%Y2O3 ceramic balls as grinding media. The milling time was varied in order to investigate the effect of the milling time on the crystallite size. The powders were investigated in terms of their crystallite sizes and morphologies by X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that under given milling conditions the powder was already nanostructured after 40 min milling. The crystallite size decreased significantly with increasing milling time within first 120 min. After that, a further increase of milling time did not lead to a significant reduction of the crystallite size. Ball-milling led to lattice microstrains. Milling with the steel balls resulted in finer nano-sized crystal grains, but caused the contamination of the powder. The nano-sized crystal grains coarsened during the heat-treatment at 1250°C.

关键词: nanostrucured powders     yttria stabilized zirconia (YSZ)     high-energy ball milling     thermal barrier coatings    

Adsorption of phosphate on magnetite-enriched particles (MEP) separated from the mill scale

Muhammad Kashif Shahid, Yunjung Kim, Young-Gyun Choi

《环境科学与工程前沿(英文)》 2019年 第13卷 第5期 doi: 10.1007/s11783-019-1151-2

摘要: MEP were separated from mill scale at low magnetic intensity i.e., 300 to 500 gauss. The phosphate adsorption capacity of MEP was determined 6.41 mg/g. MEP packed-bed columns were successfully regenerated with alkaline solution. Phosphate is a major pollutant in water, causing serious environmental and health consequences. In present study, the phosphate adsorption on novel magnetite-enriched particles (MEP) was comprehensively investigated. A new method and device were introduced for the separation of MEP from the mill scale at low magnetic intensity. Particles were characterized with different techniques such as XRD, XRF, SEM and EDS. The XRD and XRF analysis of MEP identified the dominant existence of crystalline magnetite. Furthermore, the morphological analysis of MEP confirmed the agglomerate porous morphology of magnetite. Oxygen and iron, the main constituents of magnetite were acknowledged during the elemental analysis using EDS. The phosphate adsorption on MEP is well explained using various isotherm and kinetic models, exhibiting the monolayer adsorption of phosphate on the surface of MEP. The maximum adsorption capacity was determined 6.41 mg/g. Based on particle size (45–75 and 75–150 µm) and empty bed contact time (1 and 2 h), four columns were operated for 54 days. MEP were appeared successful to remove all phosphate concentration from the column influent having 2 mg/L concentration. The operated column reactors were successfully regenerated with alkaline solution. The results indicated potential for practical application of the MEP for phosphate removal.

关键词: Adsorption     Magnetite     Mill-scale     Phosphate     Wastewater treatment    

Optimization of thermophilic anaerobic-aerobic treatment system for Palm Oil Mill Effluent (POME)

Yijing CHAN,Meifong CHONG,Chunglim LAW

《环境科学与工程前沿(英文)》 2015年 第9卷 第2期   页码 334-351 doi: 10.1007/s11783-014-0626-4

摘要: Optimization of an integrated anaerobic-aerobic bioreactor (IAAB) treatment system for the reduction of organic matter (Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD) and Total Suspended Solids (TSS) concentrations) in Palm Oil Mill Effluent (POME) to legal standards with high methane yield was performed for the first time under thermophilic condition (50°C–55°C) by using response surface methodology (RSM). The experiments were conducted based on a central composite rotatable design (CCRD) with three independent operating variables, organic loading rates in anaerobic compartment (OLR ) and mixed liquor volatile suspended solids (MLVSS) concentration in anaerobic (MLVSS ) and aerobic compartments (MLVSS ). The optimum conditions for the POME treatment were determined as OLR of 15.6 g COD·L ·d , MLVSS of 43100 mg·L , and MLVSS of 18600 mg·L , where high aerobic COD, BOD and TSS removal efficiencies of 96.3%, 97.9%, and 98.5% were achieved with treated BOD of 56 mg·L and TSS of 28 mg·L meeting the discharge standard. This optimization study successfully achieved a reduction of 42% in the BOD concentrations of the final treated effluent at a 48% higher OLR as compared to the previous works. Besides, thermophilic IAAB system scores better feasibility and higher effectiveness as compared to the optimized mesophilic system. This is due to its higher ability to handle high OLR with higher overall treatment efficiencies (more than 99.6%), methane yield (0.31 L CH ·g COD ) and purity of methane (67.5%). Hence, these advantages ascertain the applicability of thermophilic IAAB in the POME treatment or even in other high-strength wastewaters treatment.

关键词: palm oil mill effluent (POME)     anaerobic     aerobic     thermophilic     biogas     optimization    

Augmented hydrogen production by gasification of ball milled polyethylene with Ca(OH)

Giovanni Cagnetta, Kunlun Zhang, Qiwu Zhang, Jun Huang, Gang Yu

《环境科学与工程前沿(英文)》 2019年 第13卷 第1期 doi: 10.1007/s11783-019-1096-5

摘要:

PE ball milling pretreatment induces higher H2 production and purity by gasification.

Ca(OH)2 reacts at solid state with PE boosting H2 and capturing CO2.

Ca(OH)2 significantly reduces methanation side-reaction.

关键词: Hydrogen production     Gasification     Plastic waste     High energy ball milling    

Numerical solution, simulation and testing of the thermal dynamic characteristics of ball-screws

XIA Junyong, HU Youmin, WU Bo, SHI Tielin

《机械工程前沿(英文)》 2008年 第3卷 第1期   页码 28-36 doi: 10.1007/s11465-008-0007-4

摘要: This research focuses on the characteristics of how a ball-screw changes its temperature corresponding to the periodic change of the end-most heat source. Based on the theory of heat transfer, this paper supplies a numerical solution to the non-homogeneous equation of heat transfer through the group explicit (GE) finite difference approach. The temperature distribution for the ball-screw at different times and directions is shown. By simulating and modeling the temperature field and thermal deformation of the ball-screw under periodically varying heat sources, this paper describes the thermal dynamic characteristics of the ball-screw under such conditions. By testing the thermal dynamic characteristics of the ball-screw, the numerical solution is validated.

关键词: numerical solution     temperature corresponding     temperature distribution     end-most     ball-screw    

Effect of friction coefficients on the dynamic response of gear systems

BALL, Xuejun LI

《机械工程前沿(英文)》 2017年 第12卷 第3期   页码 397-405 doi: 10.1007/s11465-017-0415-4

摘要:

The inevitable deterioration of the lubrication conditions in a gearbox in service can change the tribological properties of the meshing teeth. In turn, such changes can significantly affect the dynamic responses and running status of gear systems. This paper investigates such an effect by utilizing virtual prototype technology to model and simulate the dynamics of a wind turbine gearbox system. The change in the lubrication conditions is modeled by the changes in the friction coefficients, thereby indicating that poor lubrication causes not only increased frictional losses but also significant changes in the dynamic responses. These results are further demonstrated by the mean and root mean square values calculated by the simulated responses under different friction coefficients. In addition, the spectrum exhibits significant changes in the first, second, and third harmonics of the meshing components. The findings and simulation method of this study provide theoretical bases for the development of accurate diagnostic techniques.

关键词: dynamic response     friction coefficient     wind loads     wind turbine gearbox    

适用于轧钢过程的计算机控制系统

孙一康

《中国工程科学》 2000年 第2卷 第1期   页码 73-76

摘要:

轧钢自动化,特别是带钢热连轧自动化,要求计算机控制系统具有高速控制、高速通信能力。为了推动我国轧钢自动化技术的发展,在分析国外系统发展的基础上,自行设计和集成了适用于"快速"过程的分布式计算机控制系统,这一系列已在几台热连轧机上得到应用,文章对这一系统进行了介绍。

关键词: 轧钢自动化     带钢热连轧自动化     分布式计算机控制系统     系统集成    

2300轧机上支承辊轴承座强度分析

王化川,王爱玲

《中国工程科学》 2001年 第3卷 第1期   页码 83-84

摘要:

论述了在AGC改造中上支承辊轴承座的改造,利用有限单元进行强度校核,并提出最优结果。

关键词: 轧机改造     有限单元     伺服油缸    

Kinematic error separation on five-axis NC machine tool based on telescoping double ball bar

Min WANG, Jianzhong HU, Tao ZAN

《机械工程前沿(英文)》 2010年 第5卷 第4期   页码 431-437 doi: 10.1007/s11465-010-0110-1

摘要: The theory and algorithm of the homogeneous transformation matrix (HTM) method are applied in establishing the kinematic error model of five-axis machining tool with two-axis turntable. Based on this model, a new method for the kinematic error separation in five-axis numerical control (NC) machining tool is proposed. In this study, three types of simultaneous three-axis control motions are designed for each rotary axis to identify the deviations. In the measurement, two translational axes and one rotary axis are simultaneously controlled to keep a constant distance between the tool and the worktable. Telescoping double ball bar is used to measure the relative distance between the spindle and the worktable in the motion of NC machining tool. Finally, the value measured by telescoping double ball bar is substituted into the model to obtain kinematic error of NC machining tool. Comparison has confirmed that the proposed method is high precision and can be applied to effectively and conveniently measure the five-axis machining tool.

关键词: error modeling     error separation     telescoping double ball bar     five-axis numerical control (NC) machining tool    

Elongation distribution between tension leveler and temper mill for pickling line 2030 in Baosteel

LIU Xiancui, SU Lanhai, LI Zhongfu, ZHANG Qingdong, FU Zhilin, HE Chun

《机械工程前沿(英文)》 2007年 第2卷 第3期   页码 297-300 doi: 10.1007/s11465-007-0052-4

摘要: Research into plate elongation distribution between the tension leveler and temper mill for pickling line 2030 at Baosteel is conducted. The study, which involved performance testing of mechanics, is designed at different elongation distributions and analyzed from many aspects. Finally, the optimal elongation of the tension leveler and temper mill is given.

关键词: elongation distribution     Baosteel     Research     different elongation     performance    

Erratum to: One-step ball milling-prepared nano Fe

Xingguo Guo, Qiuying Wang, Ting Xu, Kajia Wei, Mengxi Yin, Peng Liang, Xia Huang, Xiaoyuan Zhang

《环境科学与工程前沿(英文)》 2020年 第14卷 第4期 doi: 10.1007/s11783-020-1258-5

Ball milling promoted direct liquefaction of lignocellulosic biomass in supercritical ethanol

Chunyan Yang, Xiaoliang Yuan, Xueting Wang, Kejing Wu, Yingying Liu, Changjun Liu, Houfang Lu, Bin Liang

《化学科学与工程前沿(英文)》 2020年 第14卷 第4期   页码 605-613 doi: 10.1007/s11705-019-1841-0

摘要: In the present work, ball milling was applied for the pretreatment of lignocellulose to obtain high conversion and bio-oil yield in supercritical ethanol. Ball milling substantially decreased the crystallinity and particle size of lignocellulose, thereby improving its accessibility in ethanol solvent. An increased bio-oil yield of 59.2% was obtained for the ball milled camphorwood sawdust at 300°C, compared with 39.6% for the original lignocellulose. Decreased crystallinity significantly benefited the conversion of the cellulose component from 60.8% to 91.7%, and decreased particle size was beneficial for the conversion of all components. The obtained bio-oil had a high phenolic content, as analyzed by gas chromatography-mass spectrometry. Methoxylation and retro-aldol condensation were observed during alcoholysis, and the reaction pathways of lignocellulose in supercritical ethanol were attributed to the action of free radicals.

关键词: ball milling     lignocellulose     supercritical ethanol     liquefaction     bio-oil    

One-step ball milling-prepared nano Fe

Xingguo Guo, Qiuying Wang, Ting Xu, Kajia Wei, Mengxi Yin, Peng Liang, Xia Huang, Xiaoyuan Zhang

《环境科学与工程前沿(英文)》 2020年 第14卷 第2期 doi: 10.1007/s11783-019-1209-1

摘要: • Nano Fe2O3 and N-doped graphene was prepared via a one-step ball milling method. • The maximum power density of Fe-N-G in MFC was 390% of that of pristine graphite. • Active sites like nano Fe2O3, pyridinic N and Fe-N groups were formed in Fe-N-G. • The improvement of Fe-N-G was due to full exposure of active sites on graphene. Developing high activity, low-cost and long durability catalysts for oxygen reduction reaction is of great significance for the practical application of microbial fuel cells. The full exposure of active sites in catalysts can enhance catalytic activity dramatically. Here, novel Fe-N-doped graphene is successfully synthesized via a one-step in situ ball milling method. Pristine graphite, ball milling graphene, N-doped graphene and Fe-N-doped graphene are applied in air cathodes, and enhanced performance is observed in microbial fuel cells with graphene-based catalysts. Particularly, Fe-N-doped graphene achieves the highest oxygen reduction reaction activity, with a maximum power density of 1380±20 mW/m2 in microbial fuel cells and a current density of 23.8 A/m2 at –0.16 V in electrochemical tests, which are comparable to commercial Pt and 390% and 640% of those of pristine graphite. An investigation of the material characteristics reveals that the superior performance of Fe-N-doped graphene results from the full exposure of Fe2O3 nanoparticles, pyrrolic N, pyridinic N and excellent Fe-N-G active sites on the graphene matrix. This work not only suggests the strategy of maximally exposing active sites to optimize the potential of catalysts but also provides promising catalysts for the use of microbial fuel cells in sustainable energy generation.

关键词: Microbial fuel cells     Air cathodes     Nano Fe2O3 and nitrogen-doped graphene     Oxygen reduction reaction    

标题 作者 时间 类型 操作

Bioleaching of copper from pre and post thermally activated low grade chalcopyrite contained ball millspillage

Sandeep PANDA, Nilotpala PRADHAN, Umaballav MOHAPATRA, Sandeep K. PANDA, Swagat S. RATH, Danda S. RAO, Bansi D. NAYAK, Lala B. SUKLA, Barada K. MISHRA

期刊论文

Advantageous mechanochemical synthesis of copper(I) selenide semiconductor, characterization, and properties

期刊论文

characterization of nanocrystalline ZrO2-7%Y2O3 powders for thermal barrier coatings by high-energy ball

Kirsten BOBZIN, Lidong ZHAO, Thomas SCHLAEFER, Thomas WARDA

期刊论文

Adsorption of phosphate on magnetite-enriched particles (MEP) separated from the mill scale

Muhammad Kashif Shahid, Yunjung Kim, Young-Gyun Choi

期刊论文

Optimization of thermophilic anaerobic-aerobic treatment system for Palm Oil Mill Effluent (POME)

Yijing CHAN,Meifong CHONG,Chunglim LAW

期刊论文

Augmented hydrogen production by gasification of ball milled polyethylene with Ca(OH)

Giovanni Cagnetta, Kunlun Zhang, Qiwu Zhang, Jun Huang, Gang Yu

期刊论文

Numerical solution, simulation and testing of the thermal dynamic characteristics of ball-screws

XIA Junyong, HU Youmin, WU Bo, SHI Tielin

期刊论文

Effect of friction coefficients on the dynamic response of gear systems

BALL, Xuejun LI

期刊论文

适用于轧钢过程的计算机控制系统

孙一康

期刊论文

2300轧机上支承辊轴承座强度分析

王化川,王爱玲

期刊论文

Kinematic error separation on five-axis NC machine tool based on telescoping double ball bar

Min WANG, Jianzhong HU, Tao ZAN

期刊论文

Elongation distribution between tension leveler and temper mill for pickling line 2030 in Baosteel

LIU Xiancui, SU Lanhai, LI Zhongfu, ZHANG Qingdong, FU Zhilin, HE Chun

期刊论文

Erratum to: One-step ball milling-prepared nano Fe

Xingguo Guo, Qiuying Wang, Ting Xu, Kajia Wei, Mengxi Yin, Peng Liang, Xia Huang, Xiaoyuan Zhang

期刊论文

Ball milling promoted direct liquefaction of lignocellulosic biomass in supercritical ethanol

Chunyan Yang, Xiaoliang Yuan, Xueting Wang, Kejing Wu, Yingying Liu, Changjun Liu, Houfang Lu, Bin Liang

期刊论文

One-step ball milling-prepared nano Fe

Xingguo Guo, Qiuying Wang, Ting Xu, Kajia Wei, Mengxi Yin, Peng Liang, Xia Huang, Xiaoyuan Zhang

期刊论文