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One-step electrochemical reduction of stibnite concentrate in molten borax

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International Journal of Minerals,Metallurgy and Materials 2019年第10期26卷 1258-1265页

作者： Levent Kartal Mehmet Baris Daryal güldem Kartal Sireli Servet Timur Department of Metallurgical and Materials Engineering Hitit UniversityCorum 19030Turkey Department of Metallurgical and Materials Engineering Istanbul Technical UniversityIstanbul 34469Turkey

In this study,antimony production from a stibnite concentrate(Sb2S3)was performed in one step using a molten salt electrolysis method and borax as an *** reduction of the stibnite concentrate was performed at 800℃under galvanostatic conditions and explained in detail by the reactions and intermediate compounds formed in the *** effects of current density(100 800 mA cm^-2)and electrolysis time(10 40 min)on cathodic current efficiency and antimony yields were systematically *** the highest current efficiency,which was obtained at 600 mA cm^-2,direct metal production was possible with 62%cathodic current efficiency and approximately 6 kWh/kg energy *** the end of the 40-min electrolysis duration at 600 mA cm^-2 current density,antimony reduction reached 30.7 g and 99%of the antimony fed to the cell was obtained as metal.

关键词： molten salt electrolysis electrochemical reduction antimony antimony extraction stibnite borax

Discussion on Performance Evaluation Method of Distributed Combined Cooling, Heating, and Power System

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Journal of Thermal Science 2019年第6期28卷 1212-1220页

作者： SHAO Youyuan CHEN Baiman XIAO Hanmin QIN Frank g.F. guangdong Provincial Key Laboratory of Distributed Energy System School of Chemical Engineering and Energy Technology Dongguan University of Technology

This paper briefly analyzed some problems and limitations of existing evaluation indicators for distributed energy system performance. Based on the diversity and difference of the energy form and grade of cooling, heating and power in the distributed combined cooling, heating, and power(CCHP) system, this paper proposed three-index evaluation system composed of key indicators including relative energy saving rate, exergy efficiency and thermoelectric ratio. In order to further prove the reasonableness and scientificity of the evaluation index system applied in performance evaluation of distributed CCHP system, it enumerated, calculated, and evaluated the energy conservation of three engineering cases. The evaluation results showed that the high energy-saving rate of the system did not mean good energy-saving, but also the efficiency of the system should be examined. Only when the energy saving rate and exergy efficiency were both high, can the energy saving performance of the system be demonstrated. When the energy-saving rate was high and the efficiency was not high, it is shown that the energy-saving of the system had great room for improvement.

关键词： distributed energy systems(DES) energy efficiency performance index exergy analysis

Effects of laser phase transformation hardening parameters on heat input and hardened-bead profile quality of unalloyed titanium

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Transactions of Nonferrous Metals Society of China 2010年第6期20卷 1078-1091页

作者： D.S.BADKAR K.S.PANDEY g.BUVANASHEKARAN Maulana Azad National Institute of Technology Welding Research Institute Bharat Heavy Electricals Limited

Laser transformation hardening(LTH)of unalloyed titanium of 1.6 mm-thick sheet,nearer to ASTM grade 3 of chemical composition was investigated using 2 kW CW Nd:YAg *** effects of laser power(750-1 250 W),scanning speed(1 000-3 000 mm/min)and focal point position(from-10 to-30 mm)on the heat input,and hardened-bead geometry(*** bead width(HBW),hardened depth(HD)and angle of entry of hardened bead profile with the surface(AEHB))were investigated using response surface methodology(RSM).The experimental plan is based on Box-Behnken design matrix *** and quadratic polynomial equations for predicting the heat input and the hardened bead geometry were *** results indicate that the proposed models predict the responses adequately within the limits of hardening parameters being *** is suggested that regression equations can be used to find optimum hardening conditions for desired criteria.

关键词： laser transformation hardening response surface methodology(RSM) unalloyed titanium titanium hardened-bead profile

Lipid enhancement in microalgae by temporal phase separation:Use of indigenous sources of nutrients

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Chinese Journal of Chemical Engineering 2018年第1期26卷 175-182页

作者： Nidhin Sreekumar Ajit Haridas g.S.godwin N.Selvaraju National Institute of Technology(NITC) CalicutIndia National Institute for Interdisciplinary Science and Technology(NIIST) Council of Scientific&Industrial Research(CSIR)ThiruvananthapuramIndia

Microalgae have been recommended as superior candidate for fuel production because of their advantages of higher photosynthetic efficiency, biomass & lipid productivity, and faster growth rate as compared to other energy crops. To meet up all these criteria, we have developed a continuous outdoor micro-algal raceway pond reactor(RPR) and a lab scale indoor tubular photo bioreactor(PBR) for biofuel production. An attempt to utilise indigenous sources of nutrients to improve the economics also revealed that micro-algal culturing can also be used as a mode of nutrient removal and water treatment. The photosynthetic rate and lipid production were enhanced by arresting daytime cell division and promoting night-time cell division. A 50% lipid improvement was observed for the particular algal consortia. Microscopic studies revealed that temporal phase separation could be achieved by adjusting nutrient distribution pattern. To monitor temporal phase separation, it is required to know DNA multiplication model. Quantification of g DNA in RPR confirmed that cell division happens during the night which positively affects the photosynthetic efficiency and lipid productivity of microalgae.

关键词： Temporal phase separation Lipid enhancement Microalgae Biodiesel

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具有干摩擦散乱失谐的叶盘受迫响应特性

航空动力学报 2006年第4期21卷 711-715页

作者：王红建贺尔铭余仕侠西北工业大学航空学院陕西西安710072

阻尼件是叶盘结构中起减振作用的主要部件,而阻尼件的干摩擦散乱失谐会影响其在叶盘振动中的减振作用。本文利用谐波平衡法与快速傅立叶变换技术,对具有非线性干摩擦力的叶盘受迫响应进行了数学建模,仿真分析了叶盘系统在各种耦合、粘... 详细信息

阻尼件是叶盘结构中起减振作用的主要部件,而阻尼件的干摩擦散乱失谐会影响其在叶盘振动中的减振作用。本文利用谐波平衡法与快速傅立叶变换技术,对具有非线性干摩擦力的叶盘受迫响应进行了数学建模,仿真分析了叶盘系统在各种耦合、粘性阻尼比、干摩擦强度、干摩擦散乱失谐程度等参数影响下的受迫响应规律。研究结果显示,叶盘系统在弱耦合和粘性阻尼比较大的情况下,干摩擦散乱失谐会导致叶盘共振幅值显著增大。

关键词：航空航天推进系统干摩擦散乱失谐叶盘受迫振动非线性谐波平衡法

喀拉海和巴伦支海海冰对中高纬异常纬向环流暨中国东部重霾天气形成的作用

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大气科学学报 2019年第2期42卷 267-279页

作者：陈诚牛涛陆尔南京信息工程大学气象灾害教育部重点实验室/气候与环境变化国际合作联合实验室/气象灾害预报预警与评估协同创新中心江苏南京210044 中国气象局灾害天气国家重点实验室/中国气象局大气化学实验室/中国气象科学研究院北京100081

采用1981年1月—2017年2月国家气象信息中心雾、霾数据集资料、同期NCEP/NCAR再分析资料以及哈德来中心的海冰资料,分析了秋冬季喀拉海和巴伦支海海冰变化与东亚冬季风暨中国东部冬季雾和霾日数变化特征之间的关系。研究结果表明,喀拉... 详细信息

采用1981年1月—2017年2月国家气象信息中心雾、霾数据集资料、同期NCEP/NCAR再分析资料以及哈德来中心的海冰资料,分析了秋冬季喀拉海和巴伦支海海冰变化与东亚冬季风暨中国东部冬季雾和霾日数变化特征之间的关系。研究结果表明,喀拉海和巴伦支海海冰对亚洲区中高纬纬向环流有重要影响,秋季海冰异常偏少是冬季亚洲区中高纬异常纬向环流形成的诱因之一。该地区秋季海冰偏少年,冬季亚洲中高纬地区纬向环流异常偏强,东亚大槽偏弱,影响我国东部地区的东亚冬季风减弱,这为大气污染物在水平方向上的聚集提供了有利条件,同时在海冰偏少年,对流层从中层向下均为正温度距平,与地表温差减小,不利于对流发展,使得大气的状况变得更加稳定,不利于大气污染物在垂直方向上的扩散,水平和垂直方向上的共同作用导致中国东部地区易发生霾天气过程。虽然喀拉海和巴伦支海海冰是影响中国东部地区冬季霾过程发生的重要因子之一,但其对冬季中国东部雾天气发生日数多寡的影响并不显著。亚洲区纬向环流指数相比经向环流指数更能反映中国东部地区冬季雾-霾日数的变化,冬季亚洲中高纬纬向环流越强,中国东部地区雾-霾日数越多。

关键词：海冰雾霾东亚冬季风纬向环流

SerIES REPRESENTATION OF DAUBECHIES' WAVELETS

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Journal of Computational Mathematics 1997年第1期15卷 81-96页

作者： X.g. Lu (Department of Applied Mathematics, Tsinghua University, Beijing, China) 清华大学应用数学系北京

This paper gives a kind of series represeotation of the scaling functions φNand the associated wavelets . constructed by Daubechies. Based on Poission sununation formula, the functions gh. φN(x+N-1), φN (x+N),'''' φN (x+2N-2)(Ox 1) are linearly represented by φN(x), φN(x + 1),''', φN(x + 2N - 2) and some polynomials of order less than N, and φ0(x):= (φN (x), φN (x + 1),''', φN (x + N -2))t is translated into a solution of a nonhomogeneous vectorvalued functional equationwhere A0, A1 are (N - 1) x (N - 1)-dimensional matrices, the components of P0(x), P1 (x) are polynomials of order less than N. By iteration, .φ0(x) is eventualy represented as an (N - 1)-dimensional vector series with vector norm where and

关键词： Pro er Math Si WAVELETS SerIES REPRESENTATION OF DAUBECHIES

Impact analysis of compressor rotor blades of an aircraft engine

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Frontiers of Structural and Civil Engineering 2019年第3期13卷 505-514页

作者： Y B SUDHIR SASTRY B g KIROS F HAILU R BUDARAPU Department of Aeronautical Engineering Institute of Aeronautical EngineeringDundigalHyderabad 500043India Department of Aeronautical Engineering College of EngineeringDefense UniversityBishoftu 1041Ethiopia School of Mechanical Sciences Indian Institute of Technology BhubaneswarBhubaneswar 752050India

Frequent failures due to foreign particle impacts are observed in compressor blades of the interceptor fighter MIg-23 aircraft engines in the Ethiopian air force,supplied by the Dejen Aviation *** this paper,we made an attempt to identify the causes of failure and hence recommend the suitable materials to withstand the foreign particle *** and stress analysis of one of the recently failed MIg-23 gas turbine compressor blades made up of the following Aluminum based alloys:6061-T6,7075-T6,and 2024-T4,has been performed,apart from the impact analysis of the rotor blades hit by a granite *** numerical results are correlated to the practical *** on the modal,stress and impact analysis and the material properties of the three considered alloys,alloy 7075-T6 has been recommended as the blade material.

关键词： axial flow compressor rotor and stator blades aircraft engine stress and impact analysis aluminum alloys

AN AUgMENTED BV SETTINg FOR FEEDBACK SWITCHINg CONTROL

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Journal of Systems Science & Complexity 2010年第3期23卷 456-466页

作者： Falk M.HANTE günter LEUgerINg Thomas I.SEIDMAN Department Mathematik Lehrstuhl für Angewandte Mathematik ⅡUniversitt Erlangen-Nürnberg Department of Mathematics and Statistics University of Maryland Baltimore County

This paper considers dynamical systems under feedback with control actions limited *** authors wish to understand the closed-loop systems as approximating multi-scale problemsin which the implementation of switching merely acts on a fast *** hybrid dynamicalsystems are extensively studied in the literature,but not much so far for feedback with partial *** becomes in particular relevant when the dynamical systems are governed by partialdifferential *** authors introduce an augmented BV setting which permits recognition ofcertain fast scale effects and give a corresponding well-posedness result for observations with such *** an application for this setting,the authors show existence of solutions for systemsof semilinear hyperbolic equations under such feedback with pointwise observations.

关键词： Feedback functions of bounded variation hybrid dynamical systems partial state observation switching control.