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Structural-morphological features and fretting resistance of nanostructured topocomposites formed by ion-plasma modification

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Journal of Physics: Conference Series 2019年第6期1260卷

作者： D N Korotaev K N Poleschenko E N Eremin G A Vershinin E E Tarasov E V Ivanova Siberian State Automobile and Highway University 5 Mira ave. Omsk 644080 Russia Omsk Research Institute of Process and Engine Manufacture (RIPEM) 283 street of B. Khmelnytskyi Omsk 644021 Russia Omsk State Technical University 11 Mira ave. Omsk 644050 Russia Dostoevsky Omsk State University 55A Mira ave. Omsk 644077 Russia FGUP Federal Research and Development Centre 'Progress' 4 5th Kordnaya street Omsk 644018 Russia Omsk Tank-Automotive Engineering Institute 119 14th military town Omsk 644098 Russia

The article proposes an approach to solving the problem of increasing fretting resistance of lock joints of blades for gas turbine engines through the creation of nanostructured topocomposites with the surface layers in a metastable state having a low shear stability in terms of vibrofriction. The authors implement the method of vacuum combined ion-plasma processing, which allows forming the surface layers of the material with mixed amorphous-nanocrystal structure and purposeful controlling the surface morphology. They show that the proposed flow diagram allows developing the required morphology from the arrays of nano-sized conglomerates of the 'asperity – cavity' type on the surface. A comparative study of fretting resistance of nanostructured topocomposites in terms of vibrofriction is carried out. It is established that the specificity of their wear is to reduce the wear rate at the initial stage.

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The development of China's Yangtze River Economic Belt:how to make it in a green way?

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Science Bulletin 2017年第9期62卷 648-651页

作者： Yushun Chen Shuanghu Zhang Desheng Huang Bai-Lian Li Junguo Liu Wenjin Liu Jing Ma Fang Wang Yong Wang Shengjun Wu Yegang Wu Jinyue Yan Chuanbo Guo Wei Xin Hao Wang Institute of Hydrobiology & State Key Laboratory of Freshwater Ecology and Biotechnology Chinese Academy of Sciences Wuhan 430072 China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research Beijing 100038 China Policy Research Center for Environment and Economy Ministry of Environmental Protection of P.R. China Beijing 100029 China Ecological Complexity and Modeling Laboratory University of California Riverside CA 92521-0124 USA School of Environmental Science and Engineering Southern University of Science and Technology of China Shenzhen 518055 China Orient Landscape Industry Group Ltd. Beijing 100015 China Department of Biological and Environmental Sciences Alabama A&M University Normal AL 35762 USA Key Laboratory of Reservoir Aquatic Environment & Research Center for Ecological Process of Three Gorges' Eco-Environment Chongqing Institute of Green and Intelligent Technology Chinese Academy of Sciences Chongqing 400714 China Institute of Eco-city Planning and Design Shanghai BoDa Development Corporation Shanghai 200333 China KTH-Royal Institute of Technology SE-10044 Stockholm Sweden & Malardalen University SE-72123 Vasteras Sweden

The Yangtze River is one of the largest and longest rivers in *** river originates in the Tibet-Qinghai Plateau(headwater reach),passes through the mountainous provinces of Sichuan,Yunnan and Chongqing(upper reach),flows into the Central Plain(middle reach)and Lower Plain(lower reach),and finally empties into the East China Sea in Shanghai(estuary).The Yangtze River Economic Belt(YREB;Fig.1)has a surface area of 2.1

关键词： In The development of China’s Yangtze River Economic Belt:how to make it in a green way

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Experimental study by online measurement of the precipitation of nickel hydroxide: Effects of operating conditions

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Chinese Journal of Chemical engineering 2015年第5期23卷 860-867页

作者： Weiwei E Jingcai Cheng Chao Yang Zaisha Mao Key Laboratory of Green Process and Engineering Institute of Process Engineering Chinese Academy of Sciences Jiangsu Marine Resources Development Research Institute

The objective of this work is using the online measurement method to study the process of precipitation of nickel hydroxide in a single-feed semi-batch stirred reactor with an internal diameter ofD = 240mm. The effects of impeller speed, impeller type, impeller diameter and feed location on the mean particle size d43 and particle size distribution （PSD） were investigated, d43 and PSD were measured online using a Malvern Insitec Liquid Pro- cess Sizer every 20 s. It was found that d43 varied between 13 kwh and 26 lain under different operating conditions, and it decreased with increasing impeller diameter. When feeding at the off-bottom distance of D/2 under lower impeller speeds, d43 was significantly smaller than that at D/3. PSDs were slightly influenced by operating conditions.

关键词： Nickel hydroxide Precipitation Particle size distribution Online measurement Stirred tank Mixing

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Effect of process Variables on Deposited Cupric Oxide Thin Film by Sol-Gel Spin Coating Technique

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IOP Conference Series: Materials Science and engineering 2018年第1期438卷

作者： Dipika Rani Bhowmik Aninda Nafis Ahmed M A Gafur Muhammed Yusuf Miah Dipa Islam Department of Applied Chemistry and Chemical Engineering (ACCE) Noakhali Science and Technology University (NSTU) Noakhali Bangladesh Pilot Plant and Process Development Centre (PP&PDC) Bangladesh Council of Scientific and Industrial Research (BCSIR) Dhaka Bangladesh Institute of Fuel Research and Development (IFRD) Bangladesh Council of Scientific and Industrial Research (BCSIR) Dhaka Bangladesh Institute of Food Science and Technology (IFST) Bangladesh Council of Scientific and Industrial Research (BCSIR) Dhaka Bangladesh

Cupric oxide were prepared by sol-gel technique and deposited onto glass substrates as thin films using spin coating method. The aim of this research was to study the effects of different spin coating speeds and solution concentrations of cupric oxide thin films on the structural, optical, electrical and physical properties of thin films. Thin films were deposited with concentration variation of the solution ranging from 0.5 M-1 M and speed variation from 1200 rpm-2400 rpm. X-ray diffraction (XRD) and UV-Vis spectrophotometer were used to characterize the structural and optical properties of the deposited films, respectively. The as-synthesized CuO thin films were also characterized using SEM. The dc electrical properties were characterized using nano-electrometer. Based on the results obtained, it was found that the electrical resistivity of the cupric oxide thin films increases as spin coating speeds increase. The optical band gap values of CuO thin films for concentration variation were found 1.47-1.27 eV and for speed variations, it was observed 1.45-1.95 eV. Decreased values of the optical energy gap were observed with increasing concentration while reverse effect was found with increasing speed of spin coating.

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Highly Productive Oxidative Biocatalysis in Continuous Flow by Enhancing the Aqueous Equilibrium Solubility of Oxygen

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Angewandte Chemie 2018年第33期130卷

作者： Michael R. Chapman Sebastian C. Cosgrove Nicholas J. Turner Nikil Kapur A. John Blacker School of Chemistry and School of Chemical and Process Engineering Institute of Process Research and Development University of Leeds Woodhouse Lane Leeds LS2 9JT UK Manchester Institute of Biotechnology 131 Princess Street Manchester M1 7DN UK School of Mechanical Engineering University of Leeds Woodhouse Lane Leeds LS2 9JT UK

We report a simple, mild, and synthetically clean approach to accelerate the rate of enzymatic oxidation reactions by a factor of up to 100 when compared to conventional batch gas/liquid systems. Biocatalytic decomposition of H 2 O 2 is used to produce a soluble source of O 2 directly in reaction media, thereby enabling the concentration of aqueous O 2 to be increased beyond equilibrium solubility under safe and practical conditions. To best exploit this method, a novel flow reactor was developed to maximize productivity (g product L −1 h −1 ). This scalable benchtop method provides a distinct advantage over conventional bio‐oxidation in that no pressurized gas or specialist equipment is employed. The method is general across different oxidase enzymes and compatible with a variety of functional groups. These results culminate in record space‐time yields for bio‐oxidation.

关键词： Biokatalyse Flussreaktoren Kontinuierlicher Fluss Oxidationen Raumzeitausbeuten

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Effect of steam explosion treatment on biomass size reduction

Effect of steam explosion treatment on biomass size reductio...

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作者： Priyanto, Dedy Eka Ueno, Shunichiro Kasai, Hidekazu Hashida, Koh Dept. of Chemical Engineering Process Development Center IHI Corporation Japan Engineering Centre IHI Corporation Japan The Forestry and Forest Product Research Institute Japan

Size reduction is essential for converting biomass into bio-fuel. It is usually performed using milling machines which consume large amount of energy. Steam explosion treatment which consists of auto-hydrolysis and rapid decompression steps, is a promising pre-treatment process to open up biomass fibers and to recover useful compounds from it. Numerous studies have investigated the effect of steam explosion on biomass composition and on bioethanol production. However, few studies have been conducted to investigate its effect on the reduction of biomass size. In this study, the effects of steam explosion conditions such as temperature and retention time, and type of biomass (hardwood and softwood) on biomass size reduction were investigated in detail using batch-type steam explosion equipment. Sakura (Prunus spp, hardwood) chips and Japanese cedar (Cryptomeria japonica, softwood) chips of 5-10 mm were used in this study. The treatment intensity is determined by a severity factor, which is established as correlation between process temperature and residence time. A rapid increase in the yield of solid biomass of size below 1 mm (fine particles) was observed when the severity factor was above 4. 2. The fraction of fine particles crossed 80%, when the severity factor was 5. 2. We concluded that temperature/pressure significantly influences biomass size reduction and that residence time and biomass type also influence biomass size reduction, particularly at lower severity (5.2). © 2016 ETA-Florence Renewable Energies.

关键词： Biomass

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Structural and Dielectric Properties of (Bi₂O₃Fe₂O₃)_0.4(Nb₂O₅)_0.6 for Different Sintering Temperature

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Materials Sciences and Applications 2016年第8期7卷 421-429页

作者： Sadia Tasnim Mowri M. A. Gafur Quazi Delwar Hossain Aninda Nafis Ahmed Muhammad Shahriar Bashar Electrical and Electronic Engineering Department Chittagong University of Engineering and Technology Chittagong Bangladesh Pilot Plant & Process Development Centre Bangladesh Council of Scientific and Industrial Research Dhaka Bangladesh Institute of Fuel Research & Development Bangladesh Council of Scientific and Industrial Research Dhaka Bangladesh

In this research work, (Bi2O3Fe2O3)0.4(Nb2O5)0.6 was made by the solid state reaction method. Samples were sintered at four different temperatures (850°C, 925°C, 1000°C and 1150°C) to s... 详细信息

In this research work, (Bi₂O₃Fe₂O₃)_0.4(Nb₂O₅)_0.6 was made by the solid state reaction method. Samples were sintered at four different temperatures (850°C, 925°C, 1000°C and 1150°C) to study the effect of sintering temperature on the various properties of the samples. X-ray diffraction analysis confirmed that single phase Bi_1.721δ_0.089Fe_1.056Nb_1.134O₇ was found when sintering temperature increased. At the same time, larger grain size was found when sintering temperature increased. From variation of dielectric loss with respect to frequency, a small peak was found when sample was sintered at higher temperature (1150°C). Dielectric constant of the sample decreases with the increase of frequency for all the samples. With the variation of temperature, DC resistivity of the samples showed that resistivity decreases with the increase of measuring temperature which indicates semiconducting nature.

关键词： XRD Niobium SEM Dielectric Constant Dielectric Loss Loss Tangent Bismuth Ferrite Resistivity

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Improvement of the prediction performance of a soft sensor model based on support vector regression for production of ultra-low sulfur diesel

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Petroleum Science 2015年第1期12卷 177-188页

作者： Saeid Shokri Mohammad Taghi Sadeghi Mahdi Ahmadi Marvast Shankar Narasimhan Department of Chemical Engineering Iran University of Science and Technology (IUST) Process and Equipment Technology Development Division Research Institute of Petroleum Industry (RIPI) Department of Chemical Engineering

A novel data-driven, soft sensor based on support vector regression （SVR） integrated with a data compression technique was developed to predict the product quality for the hydrodesulfurization （HDS） process. A wide range of experimental data was taken from a HDS setup to train and test the SVR model. Hyper-parameter tuning is one of the main challenges to improve predictive accuracy of the SVR model. Therefore, a hybrid approach using a combination of genetic algorithm （GA） and sequential quadratic programming （SQP） methods （GA-SQP） was developed. Performance of different optimization algorithms including GA-SQP, GA, pattern search （PS）, and grid search （GS） indicated that the best average absolute relative error （AARE）, squared correlation coefficient （R2）, and computation time （CT）（AARE = 0.0745, R2 = 0.997 and CT = 56 s） was accomplished by the hybrid algorithm. Moreover, to reduce the CT and improve the accuracy of the SVR model, the vector quantization （VQ） technique was used. The results also showed that the VQ technique can decrease the training time and improve prediction performance of the SVR model. The proposed method can provide a robust, soft sensor in a wide range of sulfur contents with good accuracy.

关键词： Soft sensor Support vector regression Hybrid optimization method Vector quantization Petroleum refinery Hydrodesulfurization process Gas oil

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Formation of wear resistant nanostructural topocomposite coatings on metal materials by ionic-plasma processing

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Journal of Physics: Conference Series 2018年第1期1050卷

作者： D N Korotaev E E Tarasov K N Poleschenko E N Eremin E V Ivanova Siberian State Automobile and Highway University 5 Mira ave. Omsk 644080 Russia FGUP Federal Research and Development Centre 'Progress' 4 5th Kordnaya street Omsk 644018 Russia Omsk Research Institute of Process and Engine Manufacture (RIPEM) 283 street of B. Khmelnytskyi Omsk 644021 Russia Omsk State Technical University 11 Mira ave. Omsk 644050 Russia Omsk Tank-Automotive Engineering Institute 119 14th military town Omsk 644098 Russia

The article regards formation processes of activation and dissipative energy flows under ion-plasma sputtering of coatings. It proposes an advanced system of ionic-plasma processing with the activation of the processed surface by high voltage pulses of electric potential. The authors carry out the experimental evaluation of tribological properties for the samples with coatings and study the features of their surface damage. It is established that the topokompozitny coverings, containing high-disperse nanodimensional clusters reduce probability of brittle destruction during an initial stage of operation of tribocouplings. They show that the use of high-frequency pulse oscillations under ion-plasma sputtering decreases friction ratio and increases wear resistance of coatings.

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From Dissemination to Propagation: A New Paradigm for Education Developers

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Change 2017年第4期49卷 35-42页

作者： Froyd, Jeffrey E. Henderson, Charles Cole, Renée S. Friedrichsen, Debra Khatri, Raina Stanford, Courtney Jeffrey E. Froyd is a Research Professor at Texas A&M University. His research interests include sustained adoption of improvements in learning and teaching systematic reviews in engineering education evaluation of faculty campus climates and assessment of complex learning outcomes. Charles Henderson is a Professor at Western Michigan University with a joint appointment between the Department of Physics and the Mallinson Institute for Science Education. His research focuses on promoting productive changes in higher education at the individual department institution and national levels. Renée S. Cole is an Associate Professor of Chemistry at the University of Iowa. She teaches introductory and advanced courses in chemistry and runs a research program focused on the design and assessment of instructional materials and teaching strategies and faculty professional development. Debra Friedrichsen founded and operates a small consulting company. She received her Ph.D. from Oregon State University in Chemical Engineering with a dissertation focused on engineering education. Debra also has a MBA a MS and a patent for sensor development. Raina Khatri is a doctoral student in the Mallinson Institute for Science Education at Western Michigan University. Her research focus is understanding how education developers in STEM can promote sustained adoption of their innovations. Courtney Stanford is a postdoctoral researcher in the Department of Chemistry at Virginia Commonwealth University. Her current research focuses on the identification development and assessment of process skills (also known as professional skills) in active learning undergraduate STEM classrooms.

Scholarly studies and national reports document failure of current efforts to achieve broad, sustained adoption of research-based instructional practices, despite compelling bodies of evidence supporting efficacy of many of these practices. The authors of this paper argue that many change agents who are working to promote systemic adoption of these teaching practices use approaches that are characterized by what the authors call the "dissemination paradigm." A dissemination paradigm characterizes patterns of these current, failing efforts. Change agents, working within the dissemination paradigm, try to convince adopters that their innovations can help their students. Efforts within the dissemination paradigm have not led, and are unlikely to lead, to systemic adoption. The authors offer the "propagation paradigm" as an alternative with the potential to produce improved results. Change agents, working within the propagation paradigm, engage with adopters early and often to understand their instructional systems and interactively develop a strong product adaptable to specific contexts.

关键词： Models Change Agents Teaching Methods Information Dissemination Educational Innovation Instructional Systems STEM Education Comparative Analysis

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