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Physical and Morphological Structure of Chicken Feathers (Keratin Biofiber) in Natural, Chemically and Thermally Modified Forms

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Materials Sciences and Applications 2012年第12期3卷 887-893页

作者： Débora D.Belarmino Rasiah Ladchumananandasivam Loilde D.Belarmino Juliana R.de M.Pimentel Brismark G.da Rocha Alcione O.Galvao Sania M.B.de Andrade Post-Graduate Program in Mechanical Engineering Federal University of Rio Grande do NorteNatalBrazil Post-Graduate Program in Chemistry Federal University of Rio Grande do NorteNatalBrazil

Because of the constant challenge to preserve the environment and the search for new materials, a comparative study was carried out using keratin fiber, a fibrous protein, found in the chicken feathers. Five different samples of the feather were analyzed by Scanning Electron Microscopy (SEM) and X-ray diffractometer (XRD). First in their natural form Keratin Fiber (KF);the second treated with sodium hydroxide (KFNaOH);the third and fourth samples were semi carbonized at 220℃ in an oven without atmospheric control for 24 hours (samples obtained: Clear brown (SCFC) and Dark brown (SCFD));and the fifth sample was carbonized by pyrolysis Carbonized Feathers (CF). The SEM result shows that the KF has a hollow structure, with knots and hooks. The KFNaOH structure presented rougher than that of the KF, but lost their hooks. The SCFC and SCFD presented brittle structures, but preserved the hollow structure of KF;however, it was only noticeable to a magnification of 3000 times. On the other hand, the CF, was shiny, black, and showed a higher amount of porosity with open micro-pores and micro-tubes, preserved the hollow structure of KF than any other samples studied, and also presented well-defined closed micro-tubes. From the XRD analysis of the KF, CF, KFNaOH, SCFC and SCFD, presented semi-crystalline structures, with the following indices of crystallinity, 20.09%, 18.93%, 17.97%, 15.02% and 14.31%, respectively. The CF presented smaller size crystallites, in between the micro- particulates, around 27 nm and the KFNaOH with larger size around 74 nm. From this study it was concluded that micro-porous carbon material from chicken feathers (KF) could be efficiently obtained through pyrolysis.

关键词： Feather Keratin Carbon Structure Microparticles Nanoparticles

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Some Aspects over Thixotropic Fluid Behavior

Some Aspects over Thixotropic Fluid Behavior

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2012 International Conference on Material Sciences and Manufacturing Technology(ICMSMT 2012)

作者： Hilbeth P.Azikri de Deus Guilherme S.Paez Dupim Claudio R.Avila da Silva Jr. Nucleus of Applied and Theoretical Mechanics-Nu MAT Post-graduate Program of Mechanical and Materials Engineering-PPGEM Federal University of Technology-Parana (UTFPR)

In this work some theoretical aspects of constitutive equations for thixotropic fluids and restrictions on their functional forms are formally discussed. In the current study a formal emphasis has been given to the structural nature of this substances. The behavior of thixotropic fluids is analyzed in terms of simple isothermal laminar shear flow.

关键词： Thixotropic fluids constitutive equation structural nature

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Analysis of two schemes using micro hydroelectric power (MHPs) in the Amazon with environmental sustainability and energy and economic feasibility

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Environment, Development and Sustainability 2012年第2期14卷 283-295页

作者： Quintas, Marlus C. Blanco, Claudio J.C. Mesquita, André L. Amarante Post-Graduate Program in Mechanical Engineering PPGEM/ITEC/UFPA Federal University of Pará Belém PA 66075-110 Rua Augusto Côrrea 01 Brazil Faculty of Sanitary and Environmental Engineering FAESA/ITEC/UFPA Federal University of Pará Belém PA 66075-110 Rua Augusto Côrrea 01 Brazil Faculty of Mechanical Engineering FEM/ITEC/UFPA Federal University of Pará Belém PA 66075-110 Rua Augusto Côrrea 01 Brazil

A major problem for sustainable development in the Amazon is the difficulty of supplying electric power to isolated communities, which represent a considerable share of the population. This problem has been a major obstacle to productive activities (especially extractive and agricultural) in such communities, thus significantly contributing to rural drift and creating social problems in larger cities. In that case, one way to supply electric power would be to use the huge network of small rivers in the region by implementing Micro Hydroelectric Power Plants (MHPs). However, this type of hydropower project requires a set of technical assessments in order to obtain better value for its cost-effectiveness from the perspective of sustainable development. Thus, based on a survey of energy demand and the local hydrological and topographical characteristics, two possible MHP designs for the hydrological site under analysis were suggested. Assessments of hydropower, economic and environmental aspects were developed. MHP designs were compared with the diesel generator design of the community under focus. Comparison showed that the MHP designs are feasible in terms of energy to meet local demand;economically, they are more feasible than the diesel generator and are environmentally sustainable, mainly because such designs involve low-head, run-of-river MHPs and the flooded areas were simulated and are not larger than 0.02 km ². Therefore, the information provided by these assessments constitutes important data, serving as subsidies for MHP implementation projects, which shall contribute to sustainable development in the region. © 2011 Springer Science+Business Media B.V.

关键词： Amazon Isolated communities MHP Small environmental impact

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An experimental study of gaseous exhaust emissions of diesel engine using blend of natural fatty acid methyl ester

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IOP Conference Series: Materials Science and engineering 2012年第1期36卷

作者： Agung Sudrajad Ismail Ali Khalid Samo Danny Faturachman Faculty of Mechanical Engineering University Malaysia Pahang Campus Kuala Pahang 26600 Malaysia Maritime Studies University Malaysia Terengganu Malaysia Post Graduate Program University Malaysia Pahang Malaysia

Vegetable oil form in Natural Fatty Acid Methyl Ester (FAME) has their own advantages: first of all they are available everywhere in the world. Secondly, they are renewable as the vegetables which produce oil seeds can be planted year after year. Thirdly, they are friendly with our environment, as they seldom contain sulphur element in them. This makes vegetable fuel studies become current among the various popular investigations. This study is attempt to optimization of using blend FAME on diesel engine by experimental laboratory. The investigation experimental project is comparison between using blend FAME and base diesel fuel. The engine experiment is conducted with YANMAR TF120M single cylinder four stroke diesel engine set-up at variable engine speed with constant load. The data have been taken at each point of engine speed during the stabilized engine-operating regime. Measurement of emissions parameters at difference engine speed conditions have generally indicated lower in emission NOx, but slightly higher on CO2 emission. The result also shown that the blends FAME are good in fuel consumption and potentially good substitute fuels for diesel engine

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Swan Neck Deformity Orthosis Development: Aoa (Articulated Ring Orthosis)

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Journal of Hand Therapy 2012年第4期25卷 e9-e10页

作者： Elui, Valeria M. Rodrigues, Maysa C. Purquerio, Benedito M. Fortulan, Carlos A. Fonseca, Marisa R. Neurosciences Medicine Faculty of Ribeirao Preto - University of Sao Paulo Ribeirao Preto Brazil Inter-Bioengineering Post graduate program Inter-Bioengineering EESC/FMRP/ IQSC-USP University of Sao Paulo Sao Carlos Brazil Department of Mechanical Engineering - EESC University of Sao Paulo Sao Carlos Brazil Biomechanics Medicine and Locomotor Rehabilitation Department - FMRP University of Sao Paulo Riberiao Preto Brazil

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Modeling the mini blast furnace process based on self-reducing agglomerates

Modeling the mini blast furnace process based on self-reduci...

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3rd International Meeting on Ironmaking and 2nd International Symposium on Iron Ore

作者： De Castro, José Adilson De Souza, Franciene Teixeira Da Silva, Alexandre José Federal Fluminense University Post Graduate Program on Metallurgical Engineering Mechanical Engineering Department Volta Redonda-RJ Brazil

ISBN: (纸本)9788577370320

The blast furnace process is the main supplier of hot metal in the steel industry. This process is massive user of carbon source materials as fuel and reducing agent. Recently the development of self-agglomerates has open the possibility of its direct use in mini blast furnace. This investigation aims to numerically simulate a mini blast furnace process operating with self-reducing agglomerates with low slag rate and high rates of pulverized biomass combined with oxygen injection and small coke as solid fuels. The model describes the mini blast furnace process as a counter current reactor of five phases interacting with one another. The solid phase considers small sinter, self-reducing pellets and briquettes as iron bearing materials and small coke as solid fuel charged from the top. The modeling is based on transport equations of momentum, energy and chemical species of each phase and the chemical reactions are modeled by semi-empirical equations. Model results are presented for global parameters and spatial distributions for temperature and composition for solid and gas phases. Smooth operational conditions were obtained for about 20% of self-reducing pellets combined with small sinter and coke in the burden materials. In addition, up to 100 kg/t of pulverized biomass could be injected in the mini blast furnace tuyeres.

关键词： Biomass

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Finite element modelling of steel beams with web openings

Finite element modelling of steel beams with web openings

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11th International Conference on Civil, Structural and Environmental engineering Computing, Civil-Comp 2007

作者： Rodrigues, F. Da Vellasco, P.C.G.S. De Lima, L.R.O. De Andrade, S.A.L. Da Silva, J.G.S. Post-Graduate Program in Civil Engineering State University of Rio de Janeiro Brazil Structural Engineering Department State University of Rio de Janeiro Brazil Mechanical Engineering Department State University of Rio de Janeiro Brazil

ISBN: (纸本)9781905088157

Height limitations are frequent in multi-storey buildings due to zoning regulations, economic requirements and esthetical considerations. On the other hand, substantial spaces are normally required to enable the passage of large pipes and ducts beneath steel beams leading to uneconomic floor heights. The most adopted solution is the use of holes at the steel beam webs in order to enable the passage of services. Chung et al. [1], [3] state that nowadays services that require web openings up to 75% of the beam height are not uncommon. These openings could lead to a significant decrease of the beam load carrying capacity depending on the adopted holes shape, size and location. This motivated the present study that used finite elements simulations to quantitative and qualitative evaluates the structural behaviour of steel beams with web openings. This paper presents the developed finite element models using the ANSYS [6] program to investigate the structural response of steel beams with web openings. The analysis incorporated geometric and material non-linearities and were calibrated against numerical and test results to validate the proposed finite element models. The investigation also contemplated the simulations of beams with a series of holes distributed all over their length known as cellular beams. The imulations were centred at the evaluation of the different steel beams with web penings failure mechanisms and the main reasons for yours collapse modes. © 2007 Civil-Comp Press.

关键词： Finite element method

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Aspect ratio effect in a thermally-driven rectangular open cavity with an isothermal shrouding wall

Aspect ratio effect in a thermally-driven rectangular open c...

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2006 ASME International mechanical engineering Congress and Exposition, IMECE2006

作者： Franco, Admilson Teixeira Ganzarolli, Marcelo M. Federal Technological University of Paraná Post-graduate Program in Mechanical and Materials Engineering Av. Sete de Setembro 3165 Curitiba Paraná 80230-901 Brazil State University of Campinas Energy Department Campinas São Paulo 13081-970 Brazil

ISBN: (纸本)0791837904

Natural convection in a rectangular open cavity with the presence of an isothermal shrouding wall is investigated. The horizontal walls of the cavity are adiabatic. One vertical wall is heated uniformly and another is open to a fluid reservoir. The isothermal shrouding wall is placed in front of this opening forming a vertical channel. Laminar and two-dimensional flow is assumed for a Rayleigh number ranging from 103 - 106. The numerical solution is carried out with the Finite Volume-SOLA method. The cavity aspect ratios considered are B = L/H = 0.5, 3.0 e 6.0, where L and H are the cavity width and cavity height, respectively. The distance b/H between the isothermal shrouding wall and the cavity opening is considered as 0.5 and 0.2. The effects of the Rayleigh number Ra, the cavity aspect ratios B and the ratio b/H, on the streamlines, isotherms and average Nusselt number are reported. Copyright © 2006 by ASME.

关键词： Heat sinks

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Numerical simulation of a thermally- driven open cavity with a shrouding wall

Numerical simulation of a thermally- driven open cavity with...

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2006 ASME International mechanical engineering Congress and Exposition, IMECE2006

ISBN: (纸本)0791837904

Natural convection in a square open cavity with and without the presence of a shrouding wall is analyzed. One vertical wall is heated and the horizontal walls are adiabatic. The other vertical wall is open to the ambient or a fluid reservoir. A shrouding wall is placed in front of this open wall forming a vertical open channel. Laminar and two-dimensional flow is assumed for the Rayleigh number ranging from 103 to 107 and the problem is solved numerically by using the Finite Volume-SOLA method. The average Nusselt number is reported for different values of the Rayleigh number and the distance of the shrouding wall to the open cavity. Copyright © 2006 by ASME.

关键词： Natural convection

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Applying fuzzy functions and sequential coordination to optimization of machinery arrangement and pipe routing

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NAVAL ENGINEERS JOURNAL 1998年第6期110卷 43-54页

作者： Wu, BC Young, GS Schmidt, W Choppella, K Dr. Bi-Chu Wu:received a PhD in Mechanical Engineering from the University of Maryland College Park in 1991. She has worked on projects involving naval architecture design optimization solid mechanics and database development. Presently a senwr engineer with Angle Incorporated Dr Wu's research interests are in design optimization and fuzzy logic applications. Dr. Gin-Shu Young: a senior engineer with Angle Incorporated holds a PhD in Mechanical Engineering from the University of Maryland College Park. As a guest researcher with National Institute of Standards and Technologies from 1990 to 1993 he worked on vision-based navigation for autonomous vehicles. His experience also includes applications of optimization fuzzy logic neural network and genetic algorithm methods to engineering system design Mr. William Schmidt:co-founded Angle Incorporated in 1990 and has served as Vice PresidentlChiefScientist during this tame. He holds a B.Sc. in Applied Science from the Naval Acadt?my and an M.Sc. in Physics from the Naval Post Graduate School. He has cner 20 years experience in technical leadership material and personnel management. He has led the application of computer aided design (CAD) and Product Model Information Exchange to the shipbuilding industry. His experience also includes leading the amlication of model based operational analysis to support the Live Fire Test Program for DDG 51 Class Destroyers. Mr. Krishna M. Choppella:is a Sofware Engineer at Eidea Laboratories Incotporated where he works on componentbased distributed enterpvise frameworks. He has been involved in creating data analysis tools for the US Nay by integrating CAD modeis databases and graphical front ends. His work in the Masters degree program in Mechanical Engineering at the University of Texas at Austin was in di0ddase.r spectroscopy of combustion products in porous-matri burners. He received his Bachelors degree in Electrical Engineering in India. He was a Research Associate at the Centre for Laser Technology and Project Engi

Ship design is often multidisciplinary involving several design elements with various types of objectives and constraints (O/C) some easily described as mathematical formulas, others better modeled as descriptive assertions. This paper describes a method based on fuzzy functions and an integrated performance index to model O/C using descriptive assertions to be used with mathematical formulas in optimization. Another issue addressed in this paper concerns the coordination of design elements when sequentially coupled, that is, when one leads the other and the performance of the follower depends greatly on the design of the leader. Based on neuro-fuzzy techniques, the method described here coordinates and optimizes sequentially coupled elements. The two methods are applied to machinery arrangement (MA) and pipe routing (PR). Preliminary models for optimization of MA and PR are described considering convenience, producibility: engine room size, interference and location as factors in the O/C set. Some test results from MA/PR applications are presented and discussed. The methods are generic and can be extended to other elements in ship design. They are mutually independent and may be used separately Two advantages of their use are an improvement in overall performance and a reduction in the need for redesign of elements.

关键词： Optimization

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