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MnAl 1

伺服油缸 1

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

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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 Se^2– 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

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

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

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Principle and curve of planetary indexing cam mechanisms

LIU Ming-tao, ZHANG Ce, YANG Yu-hu

《机械工程前沿（英文）》 2006年第1卷第4期页码 475-478 doi: 10.1007/s11465-006-0063-6

摘要： A new type of planetary indexing cam mechanism called type !c is presented. The transmission principle of type !c is discussed. Based on the principle of formation of conjugate tooth contour, the equations of the cam s pitch curve are derived. The continuity and symmetry of the cam s pitch curve are also analyzed. It can be concluded that: 1) This type has no output institution so the output precision can be improved; 2) The asymmetrical two-ring structure is used to overcome dead point and its phase angle is equal to (π - 2π/n); 3) The continuous condition of the cam s pitch curve is that the average transmission ratio is -n in an intermittent motion period.

关键词： continuity planetary average transmission symmetry intermittent

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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

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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

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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

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Analysis of planetary gear transmission in non-stationary operations

Fakher CHAARI, Mohamed Slim ABBES, Fernando Viadero RUEDA, Alfonso Fernandez del RINCON, Mohamed HADDAR

《机械工程前沿（英文）》 2013年第8卷第1期页码 88-94 doi: 10.1007/s11465-013-0361-8

摘要：

Planetary gearboxes operate usually in non-stationary conditions generated mainly by variable loads applied to these transmissions. In order to understand the dynamic behavior of planetary gearboxes in such conditions, a mathematic model is developed including driving unit, transmission and load. The variability of load induces a variable speed of the transmission which is taken into account when characterizing the main dynamic parameter of the transmission which is the mesh stiffness function. This function is not periodic following the variability of the transmission speed. The computation of the dynamic response shows an intimate relation between the vibration amplitude level and the load value. As the load increase the vibration level increase. A combined amplitude and frequency modulation is observed which is well characterized using Short Time Fourier transform more suited than the spectral analysis.

关键词： planetary gearbox non-stationary conditions variable load dynamic response time frequency analysis

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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

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Planet position errors in planetary transmission: Effect on load sharing and transmission error

Miguel IGLESIAS, Alfonso FERNáNDEZ, Ana DE-JUAN, Ramón SANCIBRIáN, Pablo GARCíA

《机械工程前沿（英文）》 2013年第8卷第1期页码 80-87 doi: 10.1007/s11465-013-0362-7

摘要：

In this paper an advanced model of spur gear transmissions developed by the authors is used to study the influence of carrier planet pin hole position errors on the behaviour of the transmission. The model, initially conceived for external gear modeling, has been extended with internal meshing features, and thus increasing its capabilities to include planetary transmission modeling. The new features are presented, along with the summary of the model general approach. The parameters and characteristics of the planetary transmission used in the paper are introduced. The influence of carrier planet pin hole position errors on the planet load sharing is studied, and several static cases are given as examples in order to show the ability of the model. Tangential and radial planet pin hole position errors are considered independently, and the effect of the load level is also taken into account. It is also given attention to the effect on the transmission error of the transmission. Two different configurations for the planetary transmission are used, attending to the fixed or floating condition of the sun, and the differences in terms of load sharing ratio are shown.

关键词： gear planetary epicyclic transmission load sharing transmission error

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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

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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

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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

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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

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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

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美国DART航天器尽显小行星防御潜力

Chris Palmer

《工程（英文）》 2023年第24卷第5期页码 7-9 doi: 10.1016/j.eng.2023.03.002

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标题作者时间类型操作

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

期刊论文

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

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

Principle and curve of planetary indexing cam mechanisms

LIU Ming-tao, ZHANG Ce, YANG Yu-hu

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