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Sample records for fluid energy mill

  1. PULPA CUBA MILL ENERGY ASSESSMENT

    Directory of Open Access Journals (Sweden)

    Juan Pedro Hernández Touset

    2015-10-01

    Full Text Available An energy study was performed at Pulpa Cuba Paper Mill, located in Sancti Spiritus, where an energy management system was applied according to NC: ISO 50001, in order to assess the energy system by applying energy management systems for energy and water reduction in the paper mill, in which the current steam generation, distribution and consumption system is diagnosed. The proposal of a modified energy scheme with 1 MW Backpressure Steam Turbine Generator and rehabilitation of the original boiler or installing a lower capacity boiler contributes to save financial resources by the concept of water, fuel and electricity. The implementation of four projects will save 3,095,574 CUC / y and an average payback period of about 1 year is expected.

  2. Determining energy costs for milling solid matter

    Science.gov (United States)

    Guangbin, Yu., Dr.; Kuznetsova, M. M.; Marakhovskii, M. B.; Aleksina, A. A.

    2015-05-01

    The article provides findings of analytical research into the process of milling friable matter in a ball mill. We have received an expression to determine energy cost of milling with the account of the method of milling and the characteristics of the material to be ground.

  3. Yang-Mills Magneto-Fluid Unification

    OpenAIRE

    Bambah, Bindu A.; Mahajan, Swadesh M.; Mukku, Chandrasekher

    2006-01-01

    We generalize the hybrid magneto-fluid model of a charged fluid interacting with an electromagnetic field to the dynamics of a relativistic hot fluid interacting with a non-Abelian field. The fluid itself is endowed with a non-Abelian charge and the consequences of this generalization are worked out. Applications of this formalism to the Quark Gluon Plasma are suggested.

  4. Analogy between spin glasses and Yang--Mills fluids

    International Nuclear Information System (INIS)

    Holm, D.D.; Kupershmidt, B.A.

    1988-01-01

    A dictionary of correspondence is established between the dynamical variables for spin-glass fluid and Yang-Mills plasma. The Lie-algebraic interpretation of these variables is presented for the two theories. The noncanonical Poisson bracket for the Hamiltonian dynamics of an ideal spin glass is shown to be identical to that for the dynamics of a Yang--Mills fluid plasma, although the Hamiltonians differ for the two theories. This Poisson bracket is associated to the dual space of an infinite-dimensional Lie algebra of semidirect-product type

  5. Cosmological coevolution of Yang-Mills fields and perfect fluids

    International Nuclear Information System (INIS)

    Barrow, John D.; Jin, Yoshida; Maeda, Kei-ichi

    2005-01-01

    We study the coevolution of Yang-Mills fields and perfect fluids in Bianchi type I universes. We investigate numerically the evolution of the universe and the Yang-Mills fields during the radiation and dust eras of a universe that is almost isotropic. The Yang-Mills field undergoes small amplitude chaotic oscillations, as do the three expansion scale factors which are also displayed by the expansion scale factors of the universe. The results of the numerical simulations are interpreted analytically and compared with past studies of the cosmological evolution of magnetic fields in radiation and dust universes. We find that, whereas magnetic universes are strongly constrained by the microwave background anisotropy, Yang-Mills universes are principally constrained by primordial nucleosynthesis but the bound is comparatively weak with Ω YM rad

  6. Mechanical alloying and reactive milling in a high energy planetary mill

    International Nuclear Information System (INIS)

    Jiang Xianjin; Trunov, Mikhaylo A.; Schoenitz, Mirko; Dave, Rajesh N.; Dreizin, Edward L.

    2009-01-01

    Powder refinement in a planetary mill (Retsch PM 400-MA) is investigated experimentally and analyzed using discrete element modeling (DEM). Refinement is defined as the average size of the individual components in a composite powder. The specific milling dose, defined as the product of charge ratio and milling time, is used as an experimental parameter tracking the progress of the material refinement. This parameter is determined experimentally for milling of boron and titanium powders, for which the time of initiation of a self-sustained reaction is measured under different milling conditions. It is assumed that the reaction becomes self-sustaining when the same powder refinement is achieved. The DEM calculations established that the milling balls primarily roll along the milling container's perimeter. The inverse of the rate of energy dissipation resulting from this rolling motion is used as the DEM analog of the specific milling dose. The results correlate well with experimental observations.

  7. Preparation of iron sulphides by high energy ball milling

    DEFF Research Database (Denmark)

    Lin, R.; Jiang, Jianzhong; Larsen, R.K.

    1998-01-01

    The reaction of a powder mixture consisting of 50 a.% Fe and 50 a.% S during high energy ball milling has been studied by x-ray diffraction and Mossbauer spectroscopy. After around 19 h of milling FeS2 and FeS havebeen formed. By further milling the FeS compound becomes dominating and only Fe...

  8. Energy conservation achievements by New Shorrock Mills, Ahmedabad

    International Nuclear Information System (INIS)

    Rawal, N.L.; Trivedi, R.M.

    1994-01-01

    The New Shorrock Mills, Ahmedabad is a textile mill manufacturing cloth. Managerial practices like energy auditing and energy conservation monitoring introduced to conserve energy are described. Various measures implemented to conserve energy in machines power; carding, winding, warping and sizing operations; auto looms and lighting power are described. Cost reduction in terms of rupees is given. (N.B.)

  9. Nanocrystalline titanium characteristics obtained through cryogenic and high energy milling

    International Nuclear Information System (INIS)

    Rojas, P; Zuniga, A; Lavernia, E.J

    2008-01-01

    The microstructure and changes in chemical composition of Ti powders produced by cryogenic milling (modified Atritor) and by high energy milling (Spex mill) were investigated. The effect of high energy milling and cryomilling parameters, such as milling time and ball to powder ratio (BPR), on the particle size, grain size, chemistry, and structure of Ti powders were investigated using x-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The experimental results show that Ti powders with a grain size of approximately 20 nm (nanocrystalline) can be produced using the cryomilling technique. The average particle size increased initially with milling time from the original 55 μm to a maximum value of 125 after milling for 2 hours, and then decreased to 44μm after milling for 8 hours. Both the average particle size and the grain size decreased as the BPR increased. The results using Spex mill show that the particle size and grain size both decreased as the milling time increased. The oxygen, nitrogen and iron content of the powders increased with the milling time (au)

  10. High-Energy Ball-Milling of Alloys and Compounds

    International Nuclear Information System (INIS)

    Le Caer, G.; Delcroix, P.; Begin-Colin, S.; Ziller, T.

    2002-01-01

    After outlining some characteristics of high-energy ball-milling, we discuss selected examples of phase transformation and of alloy synthesis which focus on deviations from archetypal behaviours and throw light on the milling mechanisms. Some contributions of Moessbauer spectrometry to the characterization of ground materials are described.

  11. Magnetic properties of barium ferrite after milling by high energy milling (hem

    Directory of Open Access Journals (Sweden)

    Idayanti Novrita

    2017-01-01

    Full Text Available Magnetic properties of barium ferrite that were mashed by High Energy Milling (HEM has been characterized. The starting iron oxide powder (Fe2O3 and barium carbonate (BaCO3 were prepared by powder metallurgy technique by the stages of mixing, calcining, milling, compacting, and sintering. Weight ratio of Fe2O3: BaCO3 was 88.74 wt% : 17.52 wt%. Some additives such as calcium oxide (CaO, silicon dioxide (SiO2, and polyvinyl alcohol (PVA were added after calcining process. Milling by HEM was varied at 30, 60, 90, 120, and 150 minutes. The ball and container of HEM were made of stainless steel. Characterization micro structure by SEM showed that the milling time affect the grain size of the magnetic powder. The longer of milling time, the grain size was smaller and uniform. Characterization by using magnetic instrument Permagraph showed that the grain size will affect the magnetic properties of barium ferrite. Induction of remanence (Br, coercivity (HcJ, and product energy maximum (BHmax values increased with increasing milling time. The optimal magnetic properties were obtained at the time of milling 120 minutes with value of Hc = 1.97 kG, HcJ = 2.314 kOe, and BHmax = 0.64 MGOe.

  12. Direct measures of mechanical energy for knife mill size reduction

    Energy Technology Data Exchange (ETDEWEB)

    Bitra, V.S.P. [University of Tennessee; Womac, A.R. [University of Tennessee; Igathinathane, C. [Mississippi State University (MSU); Miu, P.I [University of Tennessee; Yang, Y.T. [University of Tennessee; Smith, D.R. [University of Tennessee; Chevanan, Nehru [University of Tennessee; Sokhansanj, Shahabaddine [ORNL

    2009-08-01

    Lengthy straw/stalk of biomass may not be directly fed into grinders such as hammer mills and disc refiners. Hence, biomass needs to be preprocessed using coarse grinders like a knife mill to allow for efficient feeding in refiner mills without bridging and choking. Size reduction mechanical energy was directly measured for switchgrass (Panicum virgatum L.), wheat straw (Triticum aestivum L.), and corn stover (Zea mays L.) in an instrumented knife mill. Direct power inputs were determined for different knife mill screen openings from 12.7 to 50.8 mm, rotor speeds between 250 and 500 rpm, and mass feed rates from 1 to 11 kg/min. Overall accuracy of power measurement was calculated to be 0.003 kW. Total specific energy (kWh/Mg) was defined as size reduction energy to operate mill with biomass. Effective specific energy was defined as the energy that can be assumed to reach the biomass. The difference is parasitic or no-load energy of mill. Total specific energy for switchgrass, wheat straw, and corn stover chopping increased with knife mill speed, whereas, effective specific energy decreased marginally for switchgrass and increased for wheat straw and corn stover. Total and effective specific energy decreased with an increase in screen size for all the crops studied. Total specific energy decreased with increase in mass feed rate, but effective specific energy increased for switchgrass and wheat straw, and decreased for corn stover at increased feed rate. For knife mill screen size of 25.4 mm and optimum speed of 250 rpm, optimum feed rates were 7.6, 5.8, and 4.5 kg/min for switchgrass, wheat straw, and corn stover, respectively, and the corresponding total specific energies were 7.57, 10.53, and 8.87 kWh/Mg and effective specific energies were 1.27, 1.50, and 0.24 kWh/Mg for switchgrass, wheat straw, and corn stover, respectively. Energy utilization ratios were calculated as 16.8%, 14.3%, and 2.8% for switchgrass, wheat straw, and corn stover, respectively. These

  13. Analysis of crystallite size and microdeformation crystal lattice the tungsten carbide milling in mill high energy

    International Nuclear Information System (INIS)

    Silva, F.T. da; Nunes, M.A.M.; Souza, C.P. de; Gomes, U.U.

    2010-01-01

    The tungsten carbide (WC) has wide application due to its properties like high melting point, high hardness, wear resistance, oxidation resistance and good electrical conductivity. The microstructural characteristics of the starting powders influences the final properties of the carbide. In this context, the use of nanoparticle powders is an efficient way to improve the final properties of the WC. The high energy milling stands out from other processes to obtain nanometric powders due to constant microstructural changes caused by this process. Therefore, the objective is to undertake an analysis of microstructural characteristics on the crystallite size and microdeformations of the crystal lattice using the technique of X-ray diffraction (XRD) using the Rietveld refinement. The results show an efficiency of the milling process to reduce the crystallite size, leading to a significant deformation in the crystal lattice of WC from 5h milling. (author)

  14. Effect of milling time on microstructure and properties of Nano-titanium polymer by high-energy ball milling

    Science.gov (United States)

    Wang, Bo; Wei, Shicheng; Wang, Yujiang; Liang, Yi; Guo, Lei; Xue, Junfeng; Pan, Fusheng; Tang, Aitao; Chen, Xianhua; Xu, Binshi

    2018-03-01

    Nano-titanium (Nano-Ti) was prepared by high-energy ball milling from pure Ti power and grinding agents (Epoxy resin) at room temperature. The effect of milling time on structure and properties of Nano-Ti polymer were investigated systematically. The results show that high-energy ball milling is an effective way to produce Nano-Ti polymer. The dispersion stability and compatibility between Ti power and grinding agents are improved by prolonging the milling time at a certain degree, that is to say, the optimization milling time is 240 min. The particle size of Ti powder and the diffraction peaks intensity of Ti decrease obviously as the milling time increases due to the compression stress, shear friction and other mechanical forces are formed during ball milling. FT-IR result displays that the wavenumber of all the bands move to lower wavenumber after ball milling, and the epoxy ring is open. The system internal energy rises owing to the broken epoxy group and much more Nano-Ti is formed to promote the grafting reaction between Nano-Ti and epoxy resin. The results from TEM and XPS also prove that. And the grafting ration is maximum as the milling time is 240 min, the mass loss ratio is 17.53%.

  15. Hydrophilic functionalized silicon nanoparticles produced by high energy ball milling

    Science.gov (United States)

    Hallmann, Steffen

    The mechanochemical synthesis of functionalized silicon nanoparticles using High Energy Ball Milling (HEBM) is described. This method facilitates the fragmentation of mono crystalline silicon into the nanometer regime and the simultaneous surface functionalization of the formed particles. The surface functionalization is induced by the reaction of an organic liquid, such as alkynes and alkenes with reactive silicon sites. This method can be applied to form water soluble silicon nanoparticles by lipid mediated micelle formation and the milling in organic liquids containing molecules with bi-functional groups, such as allyl alcohol. Furthermore, nanometer sized, chloroalkyl functionalized particles can be synthesized by milling the silicon precursor in the presence of an o-chloroalkyne with either alkenes or alkynes as coreactants. This process allows tuning of the concentration of the exposed, alkyl linked chloro groups, simply by varying the relative amounts of the coreactant. The silicon nanoparticles that are formed serve as the starting point for a wide variety of chemical reactions, which may be used to alter the surface properties of the functionalized nanoparticles. Finally, the use of functionalized silicon particles for the production of superhydrophobic films is described. Here HEBM proves to be an efficient method to produce functionalized silicon particles, which can be deposited to form a stable coating exhibiting superhydrophobic properties. The hydrophobicity of the silicon film can be tuned by the milling time and thus the resulting surface roughness of the films.

  16. Decomposition of intermetallics during high-energy ball-milling

    International Nuclear Information System (INIS)

    Kwon, Y.S.; Choi, P.P.; Kim, J.S.; Kwon, D.H.; Gerasimov, K.B.

    2007-01-01

    The decomposition behavior of FeSn, CoSn and CoIn 2 intermetallics under high-energy ball-milling has been investigated using X-ray diffraction, calorimetric and magnetization measurements. Upon milling a large amount of the FeSn intermetallic decomposes into Fe 5 Sn 3 and FeSn 2 , where the average grain size of the product phases stays nearly constant with milling-time. Similar observations are made for the CoSn intermetallic, which decomposes into Co 3 Sn 2 and Sn. It is suggested that the mechanically driven decomposition of FeSn and CoSn results from local melting of powder particles due to high temperature pulses during ball collisions. In contrast to FeSn and CoSn, CoIn 2 does not undergo decomposition upon milling. The different decomposition behaviors of the studied intermetallics may be attributed to the volume changes occurring with a decomposition process. Whereas a negative volume change is associated with the decomposition of FeSn and CoSn into their product phases, the decomposition of CoIn 2 leads to an increase in volume. Hence, high local stresses under ball collisions are expected to make the mechanically induced decomposition of FeSn and CoSn favorable but rather hinder the decomposition of CoIn 2

  17. Optimal energy management in pulp and paper mills

    International Nuclear Information System (INIS)

    Sarimveis, H.K.; Angelou, A.S.; Retsina, T.R.; Rutherford, S.R.; Bafas, G.V.

    2003-01-01

    In this paper, we examine the utilization of mathematical programming tools for optimum energy management of the power plant in pulp and paper mills. The objective is the fulfillment of the total plant requirements in energy and steam with the minimum possible cost. The proposed methodology is based on the development of a detailed model of the power plant using mass and energy balances and a mathematical formulation of the electrical purchase contract, which can be translated into a rigorous mixed integer linear programming optimization problem. The results show that the method can be a very useful tool for the reduction of production cost due to minimization of the fuel and electricity costs

  18. Compressed Air System Optimization Saves Energy and Improves Production at a Textile Manufacturing Mill (Peerless Division, Thomastown Mills, Inc.)

    Energy Technology Data Exchange (ETDEWEB)

    None

    2001-06-01

    This case study is one in a series on industrial firms who are implementing energy efficient technologies and system improvements into their manufacturing processes. This case study documents the activities, savings, and lessons learned on the textile manufacturing mill project.

  19. Energy-energy correlations in n=4 supersymmetric Yang-Mills theory.

    Science.gov (United States)

    Belitsky, A V; Hohenegger, S; Korchemsky, G P; Sokatchev, E; Zhiboedov, A

    2014-02-21

    We present a new approach to computing energy-energy correlations in gauge theories that exploits their relation to correlation functions and bypasses the use of scattering amplitudes. We illustrate its power by calculating energy-energy correlations in the maximally supersymmetric Yang-Mills theory in the next-to-leading order approximation.

  20. Vertically and Horizontally Mounted Wind Mills : Wind Energy Production in Tampere University of Applied Sciences

    OpenAIRE

    Evdokimova, Ekaterina

    2013-01-01

    The purpose of this thesis was to gather information about vertical and horizontal wind mills and to complete a research on wind power production by wind mills which were installed in Tampere University of Applied Sciences. The horizontally mounted wind mill Windspot 3.5 and vertically mounted wind mill Cypress were installed in summer 2011 but they started functioning and supplying energy only during 2012. In the theoretical part of this thesis wind speed and wind power production is dis...

  1. Energy performance indicator report: fluid milk plants

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    In Canada, the dairy sector consumes significant amounts of energy and is looking for new ways of saving energy. The aim of this study, performed by the Competitive Analysis Centre Inc., was to find novel energy savings ideas for fluid milk plants. For this purpose, the energy consumption of 17 fluid milk plants, which accounts for over 50% of total Canadian output, was analyzed; first, at the plant level, and then by 8 categories at the sub-plant level in order to develop benchmarks that could be applied at both these levels. The paper provides background information on Canada's fluid milk sector and outlines the methodology used to develop and apply energy efficiency measures in the sector; the study findings are also presented. This report found that the energy consumption of the Canadian fluid milk sector could be lowered by applying the energy saving proposals developed herein.

  2. Trends and Effective Use of Energy Input in the Palm Kernel Oil Mills

    Directory of Open Access Journals (Sweden)

    Bamgboye, AI.

    2007-01-01

    Full Text Available This work aims at studying the importance and the efficiency of energy use in a few palm kernel oil mills selected for their representativity. Pattern of energy use, the cost of energy per unit product, energy intensity and normalized performance indicator (NPI were determined. Results show that the medium and the large mills depend largely on fossil fuel; while the small mill depends on electricity. It was found out that the large mill has the most effective use of energy with high energy intensity. The annual cost of energy per unit product of N8,360,000 ($64,307.69; N12,262,250 ($94,325 and N13,353,870 ($102, 722.08 were obtained for small, medium and large mills respectively. The NPI results show that there was no wastage of energy through space heating in energy supplied for production within the factory site.

  3. Energy-based analysis of cone milling process for the comminution of roller compacted flakes.

    Science.gov (United States)

    Samanta, Asim Kumar; Wang, Likun; Ng, Ka Yun; Heng, Paul Wan Sia

    2014-02-28

    Cone mill is commonly used for the milling of wet and dry agglomerates in the pharmaceutical industry as it is capable of producing milled granules with desired size characteristics. The aim of this study was to evaluate the various cone mill process parameters in terms of milling rate and energy consumption for the comminution of roller compacted flakes. A placebo formulation containing microcrystalline cellulose, lactose and magnesium stearate was used to evaluate the milling performance. Results of this study showed that higher milling rate was obtained with the combination of higher impeller speed, teethed round sidearm impeller and grater screen surface profile. Either one of the later two parameters when present in any mill setting was found to be capable of shortening the residence time of flakes inside the milling chamber, thus resulting in a higher milling rate. On the other hand, selection of appropriate screen surface profile and impeller speed was very important at lowering the effective specific energy consumption during milling. Grater screen surface profile and impeller speed between 2000 and 2400 rpm were found to act synergistically as the best combination for an energy sparing process. Impeller sidearm shape was found to have no significant effect on energy consumption. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Tetracycline-ferrite nanocomposites formed via high-energy ball milling and the influence of milling conditions.

    Science.gov (United States)

    Branham, Michael Lee; Moyo, Thomas; Abdallah, Hafiz M I; Masina, Patrick

    2013-02-01

    High-energy ball milling was used to mediate the formation of nanocomposites containing tetracycline and magnetic nanoparticles. Tetracycline-HCl was ball milled for 1, 3, 5, 15, and 30 h under argon or air atmosphere with preformed Mg 0.5 Zn 0.5 Fe2O4 nanoferrites prepared by glycolthermal method. The structural, thermal, and magnetic properties of these novel materials and the effect of milling atmosphere on composition, crystallinity and cation distribution were then characterized by ICP-OES, DSC/TGA, XRPD, ATR-IR, UV-Vis and Mössbauer spectroscopy. Tetracycline underwent rapid and consecutive metal coordination events in the milling process to yield complexes characterized by bathochromic shifts in its electronic spectra and suppression of electronic absorbance at 365 nm. Changes in stretching vibrations due to the A-ring carbonyl (1616 cm(-1)), amide II nitrogen (1602 cm(-1)), and CO bond (1039 cm(-1)) indicate Mg-type interactions imposed on the metals. Exothermic oxidation of the drug at 235°C disappeared after 5h milling with the nanoferrites, and the composites formed remained thermostable up to 500°C. Tetracycline-nanoferrites (Tet-NF) are magnetic-ordered materials with a well-defined spinel-type structure. Analysis of the Mössbauer data suggests that the milling time and atmosphere have significant influence on cation distributions in Tet-NF composites. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. PbSe nanocubes obtained by high-energy milling

    Energy Technology Data Exchange (ETDEWEB)

    Rojas-Chavez, H., E-mail: hrojasc@ipn.mx [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada - IPN (Mexico); Reyes-Carmona, F. [Facultad de Quimica - UNAM (Mexico); Achimovicova, M. [Slovak Academy of Sciences, Institute of Geotechnics (Slovakia); Daneu, N. [Jozef Stefan Institute, Department for Nanostructured Materials (Slovenia); Jaramillo-Vigueras, D. [Centro de Investigacion e Innovacion Tecnologica - IPN (Mexico)

    2012-06-15

    In this study, PbSe nanocubes were obtained by high-energy milling, and their optical properties were investigated by measuring the UV-VIS-IR spectra in the range of 200-2,000 nm. The optical absorption of all samples showed a strong UV emission band at 1.45 eV. Previously, to obtain only PbSe nanocubes, an intermediate phase was identified, PbSeO{sub 3}. Although both PbSeO{sub 3} and PbSe were traced through this study, a major effort is devoted to characterize the latter. To trace how chemical transitions evolve from precursors to PbSe, X-ray diffraction and Rietveld refinement were carried out. Therefore, the following parameters were evaluated as a function of milling time: phase percentages, area-to-volume ratio, average crystallite dimensions, specific surface area, and morphology changes. To corroborate previous findings, nitrogen adsorption and transmission electron microscopy techniques were used. All the set experimental results unambiguously confirm that crystallites show a cubic morphology, with its average crystallite size distribution being around 24 nm.

  6. MINIMUM QUANTITY LUBRICANT FLOW ANALYSIS IN END MILLING PROCESSES: A COMPUTATIONAL FLUID DYNAMICS APPROACH

    Directory of Open Access Journals (Sweden)

    M. S. Najiha

    2012-12-01

    Full Text Available This paper presents a two-dimensional steady-state incompressible analysis for the minimum quantity of lubricant flow in milling operations using a computational fluid dynamics (CFD approach. The analysis of flow and heat transfer in a four-teeth milling cutter operation was undertaken. The domain of the rotating cutter along with the spray nozzle is defined. Operating cutting and boundary conditions are taken from the literature. A steady-state, pressure-based, planar analysis was performed with a viscous, realizable k-ε model. A mixture of oils and air were sprayed on the tool, which is considered to be rotating and is at a temperature near the melting temperature of the workpiece. Flow fields are obtained from the study. The vector plot of the flow field shows that the flow is not evenly distributed over the cutter surface, as well as the uneven distribution of the lubricant in the direction of the cutter rotation. It can be seen that the cutting fluid has not completely penetrated the tool edges. The turbulence created by the cutter rotation in the proximity of the tool throws oil drops out of the cutting zone. The nozzle position in relation to the feed direction is very important in order to obtain the optimum effect of the MQL flow.

  7. Effect of high-energy ball milling in the structural and textural properties of kaolinite

    Directory of Open Access Journals (Sweden)

    E. C. Leonel

    2014-06-01

    Full Text Available Through the process of high-energy ball milling it is possible to obtain solid materials with higher surface area and different particle sizes. These characteristics are very important for some application such as adsorption. Besides, applications of some clays depend on the functionalization which, for kaolinite, takes place in the aluminol groups. Modification in the structural and textural properties of kaolinite by high-energy milling can improve functionalization of kaolinite due to the exposure of aluminol groups. In this work studies were done on the influence of high-energy ball milling on the morphological properties of kaolinite, taking into account parameters such as filling of the miller, number of balls and amount of mass to be milled. Moreover, studies involving milling kinetics of purified kaolinite were carried out to verify modification in the morphology of kaolinite with milling time.

  8. Atmospheric and milling-device effects on the activation energy for crystallization of a partially amorphized Ni-Mo alloy

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Sanchez, R.; Estrada-Guel, I.; Torre, S.D. de la; Gaona-Tiburcio, C. [Centro de Investigacion en Materiales Avanzados (CIMAV), Chihuahua (Mexico); Jaramillo-Vigueras, D. [Inst. Politecnico Nacional, ESIQIE, UPALM, Mexico (Mexico); Guerrero-Paz, J. [Centro de Investigaciones en Materiales y Metalurgia, Univ. Autonoma del Estadode Hidalgo (Mexico)

    2002-07-01

    The Mo system processed through mechanical alloying (MA) technique has been widely investigated. For the composition Mo-47 at % Ni partially amorphous phase was obtained after 36 h milling time. Fe contamination was detected in the samples milled in a stainless steel container. Longer milling times have an important effect in the crystallization temperature. The peak temperature was shifted to lower temperatures as increases the milling time. Milling device, milling container, Fe and oxygen have an important effect in the rate of amorphization and in the activation energy (Q) for crystallization. Q values for samples milled under air atmosphere are lower than those observed in samples milled in argon atmosphere. (orig.)

  9. Geothermal energy production with supercritical fluids

    Science.gov (United States)

    Brown, Donald W.

    2003-12-30

    There has been invented a method for producing geothermal energy using supercritical fluids for creation of the underground reservoir, production of the geothermal energy, and for heat transport. Underground reservoirs are created by pumping a supercritical fluid such as carbon dioxide into a formation to fracture the rock. Once the reservoir is formed, the same supercritical fluid is allowed to heat up and expand, then is pumped out of the reservoir to transfer the heat to a surface power generating plant or other application.

  10. Influence of high-energy milling on structure and microstructure of asbestos-cement materials

    Science.gov (United States)

    Iwaszko, Józef; Zawada, Anna; Lubas, Małgorzata

    2018-03-01

    Asbestos-Containing Waste (ACW) in the form of a fragment from an asbestos-cement board was subjected to high-energy milling in a planetary mill at a constant rotational speed of 650 rpm and for variable milling times: 1, 2, and 3 h. The initial and the milled materials were subjected to infrared spectroscopic examination to identify the asbestos variety and to evaluate changes in the structure caused by high-energy milling. FT-IR (Fourier Transform Infrared Spectroscopy) examinations followed optical microscopy and SEM (Scanning Electron Microscopy) studies as well as X-ray analysis of the phase composition. It was found that the asbestos fibres present in the asbestos-cement board were respirable fibres with pathogenic properties. Identifying asbestos using the spectroscopic method showed that chrysotile asbestos was present in the as-received ACW while no characteristics of absorption bands from crocidolite or amosite were found. The results of the spectroscopic examinations were confirmed by the X-ray phase analysis. During SEM investigations of the milled ACW, complete loss of the fibrous structure of chrysotile was observed. The FT-IR examinations of the milled material showed that with an increased milling time, the characteristic absorption bands characteristic for chrysotile diminished and already after 2 h of milling their almost complete decay was observed. Thereby, it was confirmed that high-energy milling results in destruction of the crystalline structure of the asbestos phase. The conducted studies have shown that the treatment of asbestos-cement materials using high-energy milling is an effective method for asbestos disposal, capable of competing with other technologies and solutions. Moreover, FT-IR spectroscopy was found to be useful to identify asbestos phases and to assess changes caused by high-energy milling.

  11. High-Energy Ball Milling as Green Process To Vitrify Tadalafil and Improve Bioavailability.

    Science.gov (United States)

    Krupa, Anna; Descamps, Marc; Willart, Jean-François; Strach, Beata; Wyska, Elżbieta; Jachowicz, Renata; Danède, Florence

    2016-11-07

    In this study, the suitability of high-energy ball milling was investigated with the aim to vitrify tadalafil (TD) and improve its bioavailability. To achieve this goal, pure TD as well as binary mixtures composed of the drug and Soluplus (SL) were coprocessed by high-energy ball milling. Modulated differential scanning calorimetry (MDSC) and X-ray powder diffraction (XRD) demonstrated that after such coprocessing, the crystalline form of TD was transformed into an amorphous form. The presence of a single glass transition (T g ) for all the comilled formulations indicated that TD was dispersed into SL at the molecular level, forming amorphous molecular alloys, regardless of the drug concentration. The high values of T g determined for amorphous formulations, ranging from 70 to 147 °C, foreshow their high stability during storage at room temperature, which was verified by XRD and MDSC studies. The stabilizing effect of SL on the amorphous form of TD in comilled formulations was confirmed. Dissolution tests showed immediate drug release with sustained supersaturation in either simulated gastric fluid of pH 1.2 or in phosphate buffer of pH 7.2. The beneficial effect of both amorphization and coamorphization on the bioavailability of TD was found. In comparison to aqueous suspension, the relative bioavailability of TD was only 11% for its crystalline form and 53% for the crystalline physical mixture, whereas the bioavailability of milled amorphous TD and the comilled solid dispersion was 128% and 289%, respectively. Thus, the results provide evidence that not only the presence of polymeric surfactant but also the vitrification of TD is necessary to improve bioavailability.

  12. Solid state amorphization in the Al-Fe binary system during high energy milling

    Energy Technology Data Exchange (ETDEWEB)

    Urban, P., E-mail: purban@us.es; Montes, J. M.; Cintas, J. [University of Seville, Department of Mechanical and Materials Engineering, ETSI, Camino de los Descubrimientos s/n, Seville, 41092 (Spain); Cuevas, F. G., E-mail: fgcuevas@dqcm.uhu.es [University of Huelva, Department of Chemistry and Materials Science, ETSI, Campus La Rábida, Carretera Palos s/n, Palos de la Frontera, Huelva, 21819 (Spain)

    2013-12-16

    In the present study, mechanical alloying (MA) of Al75Fe25 elemental powders mixture was carried out in argon atmosphere, using a high energy attritor ball mill. The microstructure of the milled products at different stages of milling was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and differential scanning calorimetry (DSC). The results showed that the amorphous phase content increased by increasing the milling time, and after 50 hours the amorphization process became complete. Heating the samples resulted in the crystallization of the synthesized amorphous alloys and the appearance of the equilibrium intermetallic compounds Al{sub 5}Fe{sub 2}.

  13. Fluid Flow Nozzle Energy Harvesters

    Science.gov (United States)

    Sherrit, Stewart; Lee, Hyeong Jae; Walkenmeyer, Phillip; Winn, Tyler; Tosi, Luis Phillipe; Colonius, Tim

    2015-01-01

    Power generation schemes that could be used downhole in an oil well to produce about 1 Watt average power with long-life (decades) are actively being developed. A variety of proposed energy harvesting schemes could be used to extract energy from this environment but each of these has their own limitations that limit their practical use. Since vibrating piezoelectric structures are solid state and can be driven below their fatigue limit, harvesters based on these structures are capable of operating for very long lifetimes (decades); thereby, possibly overcoming a principle limitation of existing technology based on rotating turbo-machinery. An initial survey identified that spline nozzle configurations can be used to excite a vibrating piezoelectric structure in such a way as to convert the abundant flow energy into useful amounts of electrical power. This paper presents current flow energy harvesting designs and experimental results of specific spline nozzle/ bimorph design configurations which have generated suitable power per nozzle at or above well production analogous flow rates. Theoretical models for non-dimensional analysis and constitutive electromechanical model are also presented in this paper to optimize the flow harvesting system.

  14. Lattice energy-momentum tensor from the Yang-Mills gradient flow -- inclusion of fermion fields

    OpenAIRE

    Makino, Hiroki; Suzuki, Hiroshi

    2014-01-01

    Local products of fields deformed by the so-called Yang--Mills gradient flow become renormalized composite operators. This fact has been utilized to construct a correctly normalized conserved energy--momentum tensor in the lattice formulation of the pure Yang--Mills theory. In the present paper, this construction is further generalized for vector-like gauge theories containing fermions.

  15. Ammonia synthesis over multi-promoted iron catalysts obtained by high-energy ball-milling

    DEFF Research Database (Denmark)

    Jacobsen, C.J.H.; Jiang, Jianzhong; Mørup, Steen

    1999-01-01

    The feasibility of producing ammonia synthesis catalysts from high-energy ball-milling of a simple mixture of the constituent oxides has been investigated. The effect of ball-milling the fused oxidic precursor of the industrial KM1 ammonia synthesis catalyst has also been studied. The results show...

  16. Influence of vegetable based cutting fluids on cutting force and vibration signature during milling of aluminium metal matrix composites

    Directory of Open Access Journals (Sweden)

    S. Shankar

    2017-03-01

    Full Text Available Due to the environmental and health issues, there is an enormous requirement for developing the novel cutting fluids (CFs. The vegetable based cutting fluid (VBCFs doesn’t affect the environment, diminish the harmful effects to the operator and also enhance the machining performances such as surface roughness, tool life, minimum vibration and cutting forces. In this work, the performances of four different VBCFs like palm, coconut, sunflower, soya bean oils, and a commercial type of CFs were considered to analyze the influence of cutting fluids while measuring the cutting force and vibration signatures during milling of 7075–T6 hybrid aluminium metal matrix composite with carbide insert tool. The experiments were conducted in CNC L-MILL 55 vertical machining center, with milling tool dynamometer to measure the cutting force and a tri-axial accelerometer to measure the vibration signals. The flow rate of the VBCFs were maintained at a constant rate and the results were compared with a commercial cutting fluid. The obtained result shows that palm oil suits better than the other vegetable based cutting fluids in terms of minimum cutting force requirement and minimum vibration. Also, the experimental result shows that the cutting fluid was one of the important parameter needs to be considered which influences the cutting force and vibration signals.

  17. Intermediate milling energy optimization to enhance the characteristics of barium hexaferrite magnetic nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Hodaei, A.; Ataie, A., E-mail: aataie@ut.ac.ir; Mostafavi, E.

    2015-08-15

    Highlights: • Nano-sized BaFe{sub 12}O{sub 19} was successfully synthesized via a solid-state reaction. • Intermediate milling energy was optimized to improve BaFe{sub 12}O{sub 19} properties. • Minimum total energy of 93.7 kJ/g was necessary for formation of BaFe{sub 12}O{sub 19}. • Deviation from the optimum milling energy deteriorates the magnetic properties. - Abstract: Nano-sized barium hexaferrite particles were synthesized by mechanical activation of BaCO{sub 3} and Fe{sub 2}O{sub 3} powders mixture as starting materials. The effects of mechanical milling energy on the phase composition, morphology, thermal behavior and magnetic properties of the samples were systematically investigated by employing X-ray diffractometer, field emission scanning electron microscopy, differential thermal/thermo gravimetry analysis and vibrating sample magnetometer, respectively. The milling energy was calculated at five different levels using collision model. It was found that there is an optimum milling energy value for obtaining barium hexaferrite phase. The results revealed that applying a minimum total milling energy of 93.7 kJ/g was necessary for formation of almost single barium hexaferrite at a relatively low calcination temperature of 800 °C. FESEM micrograph of the above sample exhibited nano-size particles with a mean particle size of 80 nm. Further increase in milling energy leads to dramatic decrease in phase purity as well as magnetic characteristics of the samples. By increasing the milling energy from 93.7 to 671.9 kJ/g, saturation magnetization (M{sub s}) decreased from 22.5 to 0.39 emu/g, and also coercivity (H{sub c}) decreased from 4.28 to 1.46 kOe.

  18. Solid-state reactions to synthesize nanostructured lead selenide semiconductor powders by high-energy milling

    Energy Technology Data Exchange (ETDEWEB)

    Rojas-Chavez, H., E-mail: uu_gg_oo@yahoo.com.mx [Centro de Investigacion e Innovacion Tecnologica - IPN, Cerrada de CECATI s/n, Col. Santa Catarina, Del. Azcapotzalco (Mexico) and Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada - IPN, Legaria 694, Col. Irrigacion, Del. Miguel Hidalgo (Mexico); Reyes-Carmona, F. [Facultad de Quimica - UNAM, Circuito de la Investigacion Cientifica s/n, C.U. Del. Coyoacan (Mexico); Jaramillo-Vigueras, D. [Centro de Investigacion e Innovacion Tecnologica - IPN, Cerrada de CECATI s/n, Col. Santa Catarina, Del. Azcapotzalco (Mexico)

    2011-10-15

    Highlights: {yields} PbSe synthesized from PbO instead of Pb powder do not require an inert atmosphere. {yields} During high-energy milling oxygen has to be chemically reduced from the lead oxide. {yields} Solid-state and solid-gas chemical reactions promote both solid and gaseous products. -- Abstract: Both solid-solid and gas-solid reactions have been traced during high-energy milling of Se and PbO powders under vial (P, T) conditions in order to synthesize the PbSe phase. Chemical and thermodynamic arguments are postulated to discern the high-energy milling mechanism to transform PbO-Se micropowders onto PbSe-nanocrystals. A set of reactions were evaluated at around room temperature. Therefore an experimental campaign was designed to test the nature of reactions in the PbO-Se system during high-energy milling.

  19. Effect of ball milling energy on rheological and thermal properties of amaranth flour.

    Science.gov (United States)

    Roa, Diego F; Baeza, Rosa I; Tolaba, Marcela P

    2015-12-01

    Pearled amaranth grains obtained by abrasive milling were processed by planetary ball milling to produce amaranth flours. The influence of milling energy on rheological and thermal behavior of amaranth flour dispersions and stability during 24 h storage at 4 °C were investigated based on a factorial design. The rheological behavior of flour dispersions (4 % and 8 % w/v) was determined using a rotational viscometer, while gelatinization degree was determined by differential scanning calorimetry as a measure of structural changes.The power law model was found to be suitable in expressing the relationship between shear stress and shear rate. Flour dispersions showed a pseudoplastic behavior. However this character decreased with the storage being dependent on flour concentration and milling energy. A decrease of the consistency index and an increase of the flow behavior index were observed as a result of the increasing milling energy. Gelatinization enthalpy decrease showed the loss of crystalline structure due to ball milling. Amaranth flour dispersions presented increasing stability during storage. It was observed, that the stability changed with the concentration of amaranth flours.Thus, more stable dispersions were obtained as the flour concentration increased. The highly milled sample was the most stable sample during the storage.

  20. Fabrication of CNT Dispersion Fluid by Wet-Jet Milling Method for Coating on Bipolar Plate of Fuel Cell

    Directory of Open Access Journals (Sweden)

    Anas Almowarai

    2015-01-01

    Full Text Available Water based carbon nanotube (CNT dispersion was produced by wet-jet milling method. Commercial CNT was originally agglomerated at the particle size of less than 1 mm. The wet-jet milling process exfoliated CNTs from the agglomerates and dispersed them into water. Sedimentation of the CNTs in the dispersion fluid was not observed for more than a month. The produced CNT dispersion was characterized by the SEM and the viscometer. CNT/PTFE composite film was formed with the CNT dispersion in this study. The electrical conductivity of the composite film increased to 10 times when the CNT dispersion, which was produced by the wet-jet milling method, was used as a constituent of the film. Moreover, the composite film was applied to bipolar plate of fuel cell and increased the output power of the fuel cell to 1.3 times.

  1. Synthesis of niobium carbide (NbC) by powder metallurgy high energy milling technique

    International Nuclear Information System (INIS)

    Antonello, Rodrigo Tecchio; Urtiga Filho, Severino Leopoldino; Araujo Filho, Oscar Olimpio de; Ambrozio Filho, Francisco; Gonzalez, Cezar Henrique

    2009-01-01

    The aim of this work is to obtain and characterize the Niobium Carbide (NbC) by a suitable high energy milling technique using a SPEX Mill vibratory type and niobium and carbon (graphite) powders. Since this carbide is scarce in the national market and it's necessary to apply this NbC as a reinforcement in two molybdenum high speed steels (AISI M2 and AISI M3:2) object of another work motivated this research. The powders were submitted to a high energy milling procedure for suitable times and conditions and then were characterized by means of Scanning Electronic Microscopy (SEM) and X-ray diffraction (DRX) techniques. The ball-to-powder weight ratio was 10:1. The analysed samples showed that the high-energy milling is an alternative route of the NbC synthesis. (author)

  2. The synergistic effects of combining the high energy mechanical milling and wet milling on Si negative electrode materials for lithium ion battery

    Science.gov (United States)

    Hou, Shang-Chieh; Su, Yuh-Fan; Chang, Chia-Chin; Hu, Chih-Wei; Chen, Tsan-Yao; Yang, Shun-Min; Huang, Jow-Lay

    2017-05-01

    The submicro-sized and nanostructured Si aggregated powder is prepared by combinational routes of high energy mechanical milling (HEMM) and wet milling. Milled Si powder is investigated by particle size analyzer, SEM, TEM, XPS and XRD as well as the control ones. Its electrode is also investigated by in situ XRD and electrochemical performance. Morphology reveals that combining the high energy mechanical milling and wet milling not only fracture primary Si particles but also form submicro-sized Si aggregates constructed by amorphous and nanocrystalline phases. Moreover, XPS shows that wet milling in ethanol trigger Sisbnd Osbnd CH2CH3 bonding on Si surface might enhance the SEI formation. In situ XRD analysis shows negative electrode made of submicro-sized Si aggregated powder can effectively suppress formation of crystalline Li15Si4 during lithiation and delithiation due to amorphous and nanocrystalline construction. Thus, the submicro-sized Si powder with synergistic effects combining the high energy mechanical milling and wet milling in ethanol as negative electrode performs better capacity retention.

  3. Rock Characteristics and Ball Mill Energy Requirements at ...

    African Journals Online (AJOL)

    Michael

    2015-06-01

    Jun 1, 2015 ... rate, power draw and ball mill performance. The rock types identified were conglomerate and quartzite and the main minerals were quartz, feldspars, iron oxides and sulphides. Mineralogical analysis classified the ores into hard, medium and soft. There were little differences in the mineral constituents of the ...

  4. The Effect of High Energy Ball Milling on the Dynamic Response of Aluminum Powders

    Science.gov (United States)

    Beason, Matthew T.; Justice, Andrew W.; Gunduz, Ibrahim E.; Son, Steven F.

    2017-06-01

    Ball milling is an effective method to enhance the reactivity of intermetallic reactives by reducing characteristic diffusions distances. During this process, ductile reactants are mixed into a lamellar material with nanoscale features, resulting in significant strain hardening. Plate impact experiments using a single stage light gas gun have been performed to evaluate the effect of high energy ball milling (HEBM) on the mechanical properties and dynamic response of cold pressed aluminum compacts. The average grain size of the milled material is evaluate and suggested as a method of correlating the measured response to the properties of milled composites. This material is based upon work supported by the Department of Energy, National Nuclear Security Administration, under Award Number(s) DE-NA0002377, as well as individual funding (Beason) by the Department of Defense through the NDSEG.

  5. Improving Energy Efficiency Via Optimized Charge Motion and Slurry Flow in Plant Scale Sag Mills

    Energy Technology Data Exchange (ETDEWEB)

    Raj K. Rajamani

    2006-07-21

    A research team from the University of Utah is working to make inroads into saving energy in these SAG mills. In 2003, Industries of the Future Program of the Department of Energy tasked the University of Utah team to build a partnership between the University and the mining industry for the specific purpose of reducing energy consumption in SAG mills. A partnership was formed with Cortez Gold Mines, Outokumpu Technology, Kennecott Utah Copper Corporation, and Process Engineering Resources Inc. At Cortez Gold Operations the shell and pulp lifters of the semiautogenous grinding mill was redesigned. The redesigned shell lifter has been in operation for over three years and the redesigned pulp lifter has been in operation for over nine months now. This report summarizes the dramatic reductions in energy consumption. Even though the energy reductions are very large, it is safe to say that a 20% minimum reduction would be achieved in any future installations of this technology.

  6. Energy Efficiency Feasibility Study and Resulting Plan for the Bay Mills Indian Community

    Energy Technology Data Exchange (ETDEWEB)

    Kushman, Chris [Inter-Tribal Council of Michigan, Inc., Sault Ste. Marie, MI (United States). Environmental Services Division

    2014-03-01

    In 2011 the Inter-Tribal Council of Michigan, Inc. was awarded an Energy Efficiency Development and Deployment in Indian Country grant from the U.S. Department of Energy’s Tribal Energy Program. This grant aimed to study select Bay Mills Indian Community community/government buildings to determine what is required to reduce each building’s energy consumption by 30%. The Bay Mills Indian Community (BMIC) buildings with the largest expected energy use were selected for this study and included the Bay Mills Ellen Marshall Health Center building, Bay Mills Indian Community Administration Building, Bay Mills Community College main campus, Bay Mills Charter School and the Waishkey Community Center buildings. These five sites are the largest energy consuming Community buildings and comprised the study area of this project titled “Energy Efficiency Feasibility Study and Resulting Plan for the Bay Mills Indian Community”. The end objective of this study, plan and the Tribe is to reduce the energy consumption at the Community’s most energy intensive buildings that will, in turn, reduce emissions at the source of energy production, reduce energy expenditures, create long lasting energy conscious practices and positively affect the quality of the natural environment. This project’s feasibility study and resulting plan is intended to act as a guide to the Community’s first step towards planned energy management within its buildings/facilities. It aims to reduce energy consumption by 30% or greater within the subject facilities with an emphasis on energy conservation and efficiency. The energy audits and related power consumption analyses conducted for this study revealed numerous significant energy conservation and efficiency opportunities for all of the subject sites/buildings. In addition, many of the energy conservation measures require no cost and serve to help balance other measures requiring capital investment. Reoccurring deficiencies relating to heating

  7. Getting nanometric MoO{sub 3} through chemical synthesis and high energy milling

    Energy Technology Data Exchange (ETDEWEB)

    Santos-Beltrán, M. [Centro de Investigación en Materiales Avanzados (CIMAV), Laboratorio Nacional de Nanotecnología, Miguel de Cervantes No. 120, C.P. 31136 Chihuahua, Chih. (Mexico); Paraguay-Delgado, F., E-mail: francisco.paraguay@cimav.edu.mx [Centro de Investigación en Materiales Avanzados (CIMAV), Laboratorio Nacional de Nanotecnología, Miguel de Cervantes No. 120, C.P. 31136 Chihuahua, Chih. (Mexico); Santos-Beltrán, A. [Universidad Tecnológica de Chihuahua Sur, Km. 3 Carretera Chihuahua a Aldama s/n, C.P. 31050 Chihuahua, Chih. (Mexico); Fuentes, L. [Centro de Investigación en Materiales Avanzados (CIMAV), Laboratorio Nacional de Nanotecnología, Miguel de Cervantes No. 120, C.P. 31136 Chihuahua, Chih. (Mexico)

    2015-11-05

    The effects of high energy mechanical milling (HEMM) were studied on the microstructure and optical properties of MoO{sub 3} for hexagonal and orthorhombic phases. Employing HEMM was possible change particle size as a function of mechanical milling time, as well as the small quantity transformation percentage from hexagonal to orthorhombic phase. The relationship between microstrain and optical properties generated was studied. The electronic structures were calculated using the Density Functional Theory (DFT); to determinate partial density of state (PDOS). Band gap structure calculations show a good correlation between experimental and simulated data. The approximated values of microstrain, particle size, lattice parameters and oxygen vacancies were obtained employing the Rietveld refinement of X-ray diffraction patterns. Samples were characterized by electron microscopy techniques, surface area analysis (BET), thermal-gravimetric analysis (TGA), differential scanning calorimetry (DSC) and ultraviolet–visible spectroscopy (UV–Vis). It was possible, obtain particles with size below 40 nm by 30 min milling. - Graphical abstract: Orthorhombic phase, SEM image, SAED before milling, milling NPs, Particle size and band gap variation by milling time. - Highlights: • MoO{sub 3} with hexagonal and orthorhombic structures was synthesized selectively. • By milling short time (30 m), it was possible get 40 nm diameter particles. • The band gap decrease for nanoparticles, then corroborated by simulation. • MoO{sub 3} nanoparticles get high surface area for new technologic applications.

  8. Getting nanometric MoO3 through chemical synthesis and high energy milling

    International Nuclear Information System (INIS)

    Santos-Beltrán, M.; Paraguay-Delgado, F.; Santos-Beltrán, A.; Fuentes, L.

    2015-01-01

    The effects of high energy mechanical milling (HEMM) were studied on the microstructure and optical properties of MoO 3 for hexagonal and orthorhombic phases. Employing HEMM was possible change particle size as a function of mechanical milling time, as well as the small quantity transformation percentage from hexagonal to orthorhombic phase. The relationship between microstrain and optical properties generated was studied. The electronic structures were calculated using the Density Functional Theory (DFT); to determinate partial density of state (PDOS). Band gap structure calculations show a good correlation between experimental and simulated data. The approximated values of microstrain, particle size, lattice parameters and oxygen vacancies were obtained employing the Rietveld refinement of X-ray diffraction patterns. Samples were characterized by electron microscopy techniques, surface area analysis (BET), thermal-gravimetric analysis (TGA), differential scanning calorimetry (DSC) and ultraviolet–visible spectroscopy (UV–Vis). It was possible, obtain particles with size below 40 nm by 30 min milling. - Graphical abstract: Orthorhombic phase, SEM image, SAED before milling, milling NPs, Particle size and band gap variation by milling time. - Highlights: • MoO 3 with hexagonal and orthorhombic structures was synthesized selectively. • By milling short time (30 m), it was possible get 40 nm diameter particles. • The band gap decrease for nanoparticles, then corroborated by simulation. • MoO 3 nanoparticles get high surface area for new technologic applications

  9. Comparison of combustion and pyrolysis for energy generation in a sugarcane mill

    International Nuclear Information System (INIS)

    Nsaful, F.; Görgens, J.F.; Knoetze, J.H.

    2013-01-01

    Highlights: • Biomass to energy processes for sugarmills via combustion and pyrolysis are modelled. • Models compared based on technical and economic performance for two mill efficiencies. • Combustion more suited for sugar mill energy supply. • Pyrolysis based models have higher overall process efficiencies. • Pyrolysis contributes more towards environmental mitigation but is less profitable. - Abstract: The study focusses on the comparison of biomass to energy conversion process (BMECP) models to convert sugar mill biomass (bagasse) into energy products via combustion and pyrolysis as thermochemical pathways. Bagasse was converted to steam and electricity via combustion using 40 bar, 63 bar and 82 bar Condensing Extraction Steam Turbines (CEST) systems and a 30 bar back pressure steam turbine (BPST) system. Two BMECPs, namely partial fast pyrolysis and pure fast pyrolysis systems, were modeled for the pyrolysis pathway. In the Pure Fast Pyrolysis BMECP all the input bagasse stream was converted to pyrolysis products, with subsequent combustion of some of these products to generate steam and electricity for sugar mill operations. In the partial fast pyrolysis BMECP, a fraction of the bagasse is combusted directly to supply steam and electricity to the sugar mill, while the remaining fraction is pyrolyzed to generate pyrolysis products. All process models were simulated in AspenPlus® and were assessed on their ability to supply the energy requirement of to two sugar mill scenarios: More efficient mill and less efficient mill. The economic viability of BMECPs was determined using Aspen Process Economic Analyzer. Both combustion based and pyrolysis based BMECPs were capable of meeting the energy requirement of the sugar mill, although the pyrolysis based BMECP had limited steam and electricity production rates due to the accumulation of energy in pyrolysis products. High energy valued pyrolysis products resulted in higher overall process efficiencies of 85

  10. Effect of milling on particle shape and surface energy heterogeneity of needle-shaped crystals.

    Science.gov (United States)

    Ho, Raimundo; Naderi, Majid; Heng, Jerry Y Y; Williams, Daryl R; Thielmann, Frank; Bouza, Peter; Keith, Adam R; Thiele, Greg; Burnett, Daniel J

    2012-10-01

    Milling and micronization of particles are routinely employed in the pharmaceutical industry to obtain small particles with desired particle size characteristics. The aim of this study is to demonstrate that particle shape is an important factor affecting the fracture mechanism in milling. Needle-shaped crystals of the β polymorph of D-mannitol were prepared from recrystallization in water. A portion of the recrystallized materials was ball-milled. Unmilled and milled sieved fractions of recrystallized D-mannitol were analyzed by dynamic image analysis (DIA) and inverse gas chromatography (IGC) at finite concentration to explain the breakage/fracture behavior. In the process of ball-milling, D-mannitol preferentially fractured along their shortest axis, exposing (011) plane with increased hydrophilicity and increased bounding rectangular aspect ratio. This is in contrary to attachment energy modeling which predicts a fracture mechanism across the (010) plane with increased hydrophobicity, and small change in particle shape. Crystal size, and more importantly, crystal shape and facet-specific mechanical properties, can dictate the fracture/cleavage behavior of organic crystalline materials. Thorough understanding of the crystal slip systems, combining attachment energy prediction with particle shape and surface characterization using DIA and IGC, are important in understanding fracture behavior of organic crystalline solids in milling and micronization.

  11. Energy efficiency improvement and cost saving opportunities for the Corn Wet Milling Industry: An ENERGY STAR Guide for Energy and Plant Managers

    Energy Technology Data Exchange (ETDEWEB)

    Galitsky, Christina; Worrell, Ernst; Ruth, Michael

    2003-07-01

    Corn wet milling is the most energy intensive industry within the food and kindred products group (SIC 20), using 15 percent of the energy in the entire food industry. After corn, energy is the second largest operating cost for corn wet millers in the United States. A typical corn wet milling plant in the United States spends approximately $20 to $30 million per year on energy, making energy efficiency improvement an important way to reduce costs and increase predictable earnings, especially in times of high energy-price volatility. This report shows energy efficiency opportunities available for wet corn millers. It begins with descriptions of the trends, structure and production of the corn wet milling industry and the energy used in the milling and refining process. Specific primary energy savings for each energy efficiency measure based on case studies of plants and references to technical literature are provided. If available, typical payback periods are also listed. The report draws upon the experiences of corn, wheat and other starch processing plants worldwide for energy efficiency measures. The findings suggest that given available resources and technology, there are opportunities to reduce energy consumption cost-effectively in the corn wet milling industry while maintaining the quality of the products manufactured. Further research on the economics of the measures, as well as the applicability of these to different wet milling practices, is needed to assess the feasibility of implementation of selected technologies at individual plants.

  12. Influence of milling process in the surface energy of glass tile frits

    International Nuclear Information System (INIS)

    Tamayo, A.; Rubio, F.; Otero, J. L.; Rubio, J.

    2013-01-01

    In this work has been studied the influence of the milling process of two ceramic frits used in the ceramic tile industry. Both glass frits were of similar chemical composition changing SiO 2 by 5% of B 2 O 3 and both of them were water or dry milled. Glass frit surfaces were characterized by FT-IR, Karl-Fischer (K-F) titration and Inverse Gas Chromatography at Infinite Dilution (IGC-ID). By K-F titration it was observed that water milled frits presented 28 and 26 OH groups for 100 A 2 if they do not contain or contain boron, respectively. These surface changes are also observed by IGC-ID. Thus, the glass frit without boron and dry milled presented the highest dispersive surface energy (44 mJ.m - 2) and the less acidic constant (0.13 kJ.mol - 1). Both glass frits are amphoteric with acidic and base surface active sites, and that frit without boron presents the higher basicity. Milling process influences in the acid-base surface characteristics of both frits by increasing the basicity for the one without boron and increasing for the other one. This has been assigned to the different location of hydroxyl groups where the higher interaction is the one that does not contain boron and dry milled as K-F results. (Author)

  13. An Energy Preserving Monolithic Eulerian Fluid-Structure Numerical Scheme *

    OpenAIRE

    Pironneau, Olivier

    2016-01-01

    The conservation laws of continuum mechanic written in an Eulerian frame make no difference between fluids and solids except in the expression of the stress tensors, usually with Newton's hypothesis for the fluids and Helmholtz potentials of energy for hyperelastic solids. By taking the velocities as unknown , monolithic methods for fluid structure interactions (FSI) are built. In this article such a formulation is analyzed when the fluid is compressible and the fluid is incompressible. The i...

  14. An Energy stable Monolithic Eulerian Fluid-Structure Numerical Scheme *

    OpenAIRE

    Pironneau , Olivier

    2017-01-01

    The conservation laws of continuum mechanic written in an Eulerian frame make no difference between fluids and solids except in the expression of the stress tensors, usually with Newton's hypothesis for the fluids and Helmholtz potentials of energy for hyperelastic solids. By taking the velocities as unknown , monolithic methods for fluid structure interactions (FSI) are built. In this article such a formulation is analyzed when the fluid is compressible and the fluid is incompressible. The i...

  15. Microstructural analysis of sinterized aluminum powder obtained by the high energy milling of beverage cans

    International Nuclear Information System (INIS)

    Souza, Jose Raelson Pereira de; Peres, Mauricio Mhirdaui

    2016-01-01

    The objective is the study of the effect of high energy milling on the sintering of aluminum from beverage cans. The selected aluminum cans were cut and subjected to high energy milling under a common atmosphere (in the air). In milling, three grams of aluminum was used to maintain the ratio of 10/1 between the mass of the beads and the material. The milling time was varied in 1h, 1.5h and 2h, keeping the other variables constant. The particle size distribution was measured by laser granulometry, for further compaction and sintering at a temperature of 600 ° C for 2 h. The samples were characterized by scanning electron microscopy (SEM). The granulometric analysis of the powders found that higher milling times produced finer particles. Powders with granulometry of less than 45 μm were obtained at 1 h, 1.5 h and 2 h times. The times of 1.5h and 2h promoted finer particles with better distribution of size. The SEM analyzes showed little variation in the shape of the particles as a function of the variation of the grinding times, presenting irregularities in the platelet geometry. The sintering time and temperature were effective in the densification of the powder particles, which were influenced by the average particle size

  16. Generalized dark energy interactions with multiple fluids

    International Nuclear Information System (INIS)

    De Bruck, Carsten van; Mifsud, Jurgen; Mimoso, José P.; Nunes, Nelson J.

    2016-01-01

    In the search for an explanation for the current acceleration of the Universe, scalar fields are the most simple and useful tools to build models of dark energy. This field, however, must in principle couple with the rest of the world and not necessarily in the same way to different particles or fluids. We provide the most complete dynamical system analysis to date, consisting of a canonical scalar field conformally and disformally coupled to both dust and radiation. We perform a detailed study of the existence and stability conditions of the systems and comment on constraints imposed on the disformal coupling from Big-Bang Nucleosynthesis and given current limits on the variation of the fine-structure constant.

  17. Generalized dark energy interactions with multiple fluids

    Energy Technology Data Exchange (ETDEWEB)

    De Bruck, Carsten van; Mifsud, Jurgen [Consortium for Fundamental Physics, School of Mathematics and Statistics, University of Sheffield, Hounsfield Road, Sheffield S3 7RH (United Kingdom); Mimoso, José P.; Nunes, Nelson J., E-mail: c.vandebruck@sheffield.ac.uk, E-mail: jmifsud1@sheffield.ac.uk, E-mail: jpmimoso@fc.ul.pt, E-mail: njnunes@fc.ul.pt [Instituto de Astrofísica e Ciências do Espaço, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, PT1749-016 Lisboa (Portugal)

    2016-11-01

    In the search for an explanation for the current acceleration of the Universe, scalar fields are the most simple and useful tools to build models of dark energy. This field, however, must in principle couple with the rest of the world and not necessarily in the same way to different particles or fluids. We provide the most complete dynamical system analysis to date, consisting of a canonical scalar field conformally and disformally coupled to both dust and radiation. We perform a detailed study of the existence and stability conditions of the systems and comment on constraints imposed on the disformal coupling from Big-Bang Nucleosynthesis and given current limits on the variation of the fine-structure constant.

  18. Transformation of Goethite to Hematite Nanocrystallines by High Energy Ball Milling

    Directory of Open Access Journals (Sweden)

    O. M. Lemine

    2014-01-01

    Full Text Available α-Fe2O3 nanocrystallines were prepared by direct transformation via high energy ball milling treatment for α-FeOOH powder. X-ray diffraction, Rietveld analysis, TEM, and vibrating sample magnetometer (VSM are used to characterize the samples obtained after several milling times. Phase identification using Rietveld analysis showed that the goethite is transformed to hematite nanocrystalline after 40 hours of milling. HRTEM confirm that the obtained phase is mostly a single-crystal structure. This result suggested that the mechanochemical reaction is an efficient way to prepare some iron oxides nanocrystallines from raw materials which are abundant in the nature. The mechanism of the formation of hematite is discussed in text.

  19. Exfoliation of graphene sheets via high energy wet milling of graphite in 2-ethylhexanol and kerosene.

    Science.gov (United States)

    Al-Sherbini, Al-Sayed; Bakr, Mona; Ghoneim, Iman; Saad, Mohamed

    2017-05-01

    Graphene sheets have been exfoliated from bulk graphite using high energy wet milling in two different solvents that were 2-ethylhexanol and kerosene. The milling process was performed for 60 h using a planetary ball mill. Morphological characteristics were investigated using scanning electron microscope (SEM) and transmission electron microscope (TEM). On the other hand, the structural characterization was performed using X-ray diffraction technique (XRD) and Raman spectrometry. The exfoliated graphene sheets have represented good morphological and structural characteristics with a valuable amount of defects and a good graphitic structure. The graphene sheets exfoliated in the presence of 2-ethylhexanol have represented many layers, large crystal size and low level of defects, while the graphene sheets exfoliated in the presence of kerosene have represented fewer number of layers, smaller crystal size and higher level of defects.

  20. Exfoliation of graphene sheets via high energy wet milling of graphite in 2-ethylhexanol and kerosene

    Directory of Open Access Journals (Sweden)

    Al-Sayed Al-Sherbini

    2017-05-01

    Full Text Available Graphene sheets have been exfoliated from bulk graphite using high energy wet milling in two different solvents that were 2-ethylhexanol and kerosene. The milling process was performed for 60 h using a planetary ball mill. Morphological characteristics were investigated using scanning electron microscope (SEM and transmission electron microscope (TEM. On the other hand, the structural characterization was performed using X-ray diffraction technique (XRD and Raman spectrometry. The exfoliated graphene sheets have represented good morphological and structural characteristics with a valuable amount of defects and a good graphitic structure. The graphene sheets exfoliated in the presence of 2-ethylhexanol have represented many layers, large crystal size and low level of defects, while the graphene sheets exfoliated in the presence of kerosene have represented fewer number of layers, smaller crystal size and higher level of defects.

  1. Transformations in oxides induced by high-energy ball-milling.

    Science.gov (United States)

    Šepelák, Vladimir; Bégin-Colin, Sylvie; Le Caër, Gérard

    2012-10-21

    This paper, by no means exhaustive, focuses on high-energy ball-milling of oxides, on their mechanically induced changes and on the consequences of such changes on their physical and chemical properties. High-energy ball-milling offers a fortunate combination of technical simplicity and of complexity both of physical mechanisms which act during milling and of mechanosynthesized materials. Its basic interest, which stems from the large diversity of routes it offers to prepare oxides either directly or indirectly, is illustrated with various families of oxides. The direct path is to be favoured when as-milled oxides are of interest per se because of their nanocrystalline characteristics, their defects or their modified structures which result from mechanically driven phase transformations. The indirect path consists of a sequence of steps starting with mechanically activated oxides which may be subsequently just annealed or submitted to a combination of thermal treatments, with the possible occurrence of various chemical reactions, to prepare the sought-after materials with potential gains in processing temperatures and times. High energy ball-milling of oxides is more and more currently used to activate powders and to prepare nano-oxides at moderate temperatures. The interest of an activation step is well illustrated by the broad development of doped titania powders, synthesized by heat treatment of pre-ground reactants, for photocatalytic applications or to develop antibacterial materials. Another important class of applications of high-energy ball-milling is the formation of composites. It is exemplified here with the case of oxide-dispersed strengthened alloys whose properties are considerably improved by a dispersion of ultra-stable nanosized oxides whose formation mechanisms were recently described. The basic understanding of the mechanisms by which oxides or oxide mixtures evolve by high-energy ball-milling appears to be less advanced than it is for metallic

  2. Characterization of Al2O3-Co ceramic composite obtained by high energy mill

    International Nuclear Information System (INIS)

    Souza, J.L.; Assis, R.B. de; Carlos, E.M.; Oliveira, T.P.; Costa, F.A. da

    2014-01-01

    This work aims to characterize the ceramic composite Al 2 O3-Co obtained by high energy grinding. The composites were obtained by milling Al 2 O 3 and Co in a high energy mill at a speed of 400 rpm, in proportions of 5 to 20% Cobalt (Co). Ceramic composites with 5 and 20% cobalt were sintered at 1200 and 1300 ° C, with a 60-minute plateau and a heating rate of 10 ° C / min. The samples were characterized by X-ray diffraction (XRD), thermogravimetry and differential scanning calorimetry (TG / DSC) and scanning electron microscopy (SEM). The results show the significant effect of cobalt percentage and high energy grinding on the final properties of the Al 2 O 3 - Co ceramic composite, presenting satisfactory values for the composite with a 20% cobalt percentage, showing to be a promising material for application in cutting tools

  3. THEORETICAL AND EXPERIMENTAL STUDIES OF ENERGY-EFFICIENT GRINDING PROCESS OF CEMENT CLINKER IN A BALL MILL

    Directory of Open Access Journals (Sweden)

    Kuznetsova M.M.

    2014-08-01

    Full Text Available The article presents results of theoretical and experimental research of grinding process of bulk materials in a ball mill. The new method of determination of energy efficiently mode of operation of ball mills in a process of a cement clinker grinding is proposed and experimentally tested.

  4. Piezoelectric Energy Harvesting in Internal Fluid Flow

    Directory of Open Access Journals (Sweden)

    Hyeong Jae Lee

    2015-10-01

    Full Text Available We consider piezoelectric flow energy harvesting in an internal flow environment with the ultimate goal powering systems such as sensors in deep oil well applications. Fluid motion is coupled to structural vibration via a cantilever beam placed in a converging-diverging flow channel. Two designs were considered for the electromechanical coupling: first; the cantilever itself is a piezoelectric bimorph; second; the cantilever is mounted on a pair of flextensional actuators. We experimentally investigated varying the geometry of the flow passage and the flow rate. Experimental results revealed that the power generated from both designs was similar; producing as much as 20 mW at a flow rate of 20 L/min. The bimorph designs were prone to failure at the extremes of flow rates tested. Finite element analysis (FEA showed fatigue failure was imminent due to stress concentrations near the bimorph’s clamped region; and that robustness could be improved with a stepped-joint mounting design. A similar FEA model showed the flextensional-based harvester had a resonant frequency of around 375 Hz and an electromechanical coupling of 0.23 between the cantilever and flextensional actuators in a vacuum. These values; along with the power levels demonstrated; are significant steps toward building a system design that can eventually deliver power in the Watts range to devices down within a well.

  5. Fe-Al2O3 nanocomposites prepared by high-energy ball milling

    DEFF Research Database (Denmark)

    Linderoth, Søren; Pedersen, M.S.

    1994-01-01

    Nanocomposites of alpha-Fe and alpha-Al2O3, prepared by high-energy ball milling, exhibit coercivities which are enhanced by about two orders of magnitude with respect to the bulk value. The degree of enhancement depends on the volume fraction (x(upsilon)) of Fe, with a maximum for x(upsilon) alm......Nanocomposites of alpha-Fe and alpha-Al2O3, prepared by high-energy ball milling, exhibit coercivities which are enhanced by about two orders of magnitude with respect to the bulk value. The degree of enhancement depends on the volume fraction (x(upsilon)) of Fe, with a maximum for x...

  6. A morphological evaluation of a duplex stainless steel processed by high energy Ball Mill

    International Nuclear Information System (INIS)

    Yonekubo, Ariane Emi; Cintho, Osvaldo Mitsuyuki; Aguiar, Denilson Jose Marcolino de; Capocchi, Jose Deodoro Trani

    2009-01-01

    The duplex stainless steels are formed by a ferrite and austenite mixture, giving them a combination of properties. Commercially, these steels are hot rolled, developing an anisotropic, alternated ferrite and austenite elongated lamellae microstructure. In this work, a duplex stainless steel was produced by the mixture of elementary powders with the composition Fe-19.5Cr-5Ni processed in an ATTRITOR ball mill during periods up to 15 hours. The powders obtained were compressed in specimens and were heat treated in the temperatures of 900, 1050 and 1200 °C during 1 hour and analysed by x ray diffraction, optic microscopy, scanning electron microscopy and energy dispersion spectroscopy. An optimized microstructure with ultrafine, equiaxial and regular duplex microstructure was obtained in the 15 hour milling and 1200 °C heat treatment. Afterwards, a commercially super duplex stainless steel UNS S32520 was aged at 800 °C aiming the precipitation of σ phase in order to reduce its toughness and then, milled in SPEX mill. The resulting microstructure was a very fine duplex type with irregular grain boundary morphology duo to the grain growth barrier promoted by the renascent σ phase particles during sintering process. (author)

  7. Real time power consumption monitoring for energy efficiency analysis in micro EDM milling

    DEFF Research Database (Denmark)

    Tristo, Gianluca; Bissacco, Giuliano; Lebar, Andrej

    2015-01-01

    for manufacturing sustainability. Electrical discharge machining (EDM) is considered an attractive solution for the manufacturing of microcomponents. In this paper, a low cost and modular data acquisition system, based on open-hardware and open-source software, for online energy consumption monitoring, is presented....... The system described is applied for energy efficiency analysis of the micro EDM milling process by using a state of the art commercial machine tool. A number of sensors is connected to the data acquisition system to measure the energy consumption of the main sub-systems of the machine tool, data is recorded...

  8. Refining the microstructure of an AISI M2 tool steel by high-energy milling

    International Nuclear Information System (INIS)

    Postiglioni, R.V.; Alamino, A.E; Vurobi Junior, S.

    2009-01-01

    Samples of AISI M2 steel were produced by high-energy milling from chips of machining in Spex high energy mill, compaction and sintering of the powder obtained. The powder was analyzed by X-ray diffraction, and then compressed in discs of 8mm in diameter. The specimens have sintering at 1200 deg C for 1 hour under vacuum atmosphere, followed by annealing, quenching and tempering for 1 hour at 315 deg C and 540°C. Along with each disc, a sample of as-received steel was subjected to the same heat treatments to compare the final microstructure. After standard metallographic preparation, samples were etched with Beraha's reagent, characterized by optical microscopy, quantitative metallography, scanning electron microscopy with micro analysis and mapping by EDS, besides Vickers hardness. The steel produced by high-energy milling presented more refined carbide and better distribution in the microstructure. There was also reduction in the size of prior austenitic grains. (author)

  9. Fluid manifold design for a solar energy storage tank

    Science.gov (United States)

    Humphries, W. R.; Hewitt, H. C.; Griggs, E. I.

    1975-01-01

    A design technique for a fluid manifold for use in a solar energy storage tank is given. This analytical treatment generalizes the fluid equations pertinent to manifold design, giving manifold pressures, velocities, and orifice pressure differentials in terms of appropriate fluid and manifold geometry parameters. Experimental results used to corroborate analytical predictions are presented. These data indicate that variations in discharge coefficients due to variations in orifices can cause deviations between analytical predictions and actual performance values.

  10. Modeling on the Effect of Coal Loads on Kinetic Energy of Balls for Ball Mills

    Directory of Open Access Journals (Sweden)

    Yan Bai

    2015-07-01

    Full Text Available This paper presents a solution for the detection and control of coal loads that is more accurate and convenient than those currently used. To date, no research has addressed the use of a grinding medium as the controlled parameter. To improve the accuracy of the coal load detection based on the kinetic energy of balls in a tubular ball mill, a Discrete Element Method (DEM model for ball kinematics based on coal loads is proposed. The operating process for a ball mill and the ball motion, as influenced by the coal quality and the coal load, was analyzed carefully. The relationship between the operating efficiency of a coal pulverizing system, coal loads, and the balls’ kinetic energy was obtained. Origin and Matlab were utilized to draw the variation of parameters with increasing coal loads in the projectile and cascading motion states. The parameters include the balls’ real-time kinetic energy, the friction energy consumption, and the mill’s total work. Meanwhile, a method of balanced adjacent degree and a physical experiment were proposed to verify the considerable effect of the balls’ kinetic energy on coal loads. The model and experiment results indicate that a coal load control method based on the balls’ kinetic energy is therefore feasible for the optimized operation of a coal pulverizing system.

  11. High energy milling of zirconia-titania powders synthesized by coprecipitation

    International Nuclear Information System (INIS)

    Silva, Cristiano M.B.; Marchi, Juliana; Lazar, Dolores R.R.; Ussui, Valter

    2009-01-01

    Zirconia based ceramics are known by its remarkable mechanical properties as hardness and fracture toughness and in biomedical applications are classified as bioinert. By its turn, titania ceramics has been studied due to its ability to bond directly to bone tissue, but are structurally brittle. Properties of ceramics are strongly dependent of physical and chemical characteristics of its former powders. In the present work, research done for the synthesis of zirconia-titania ceramics by the coprecipitation route are presented, emphasizing the conditioning process through a high energy milling in a atritor mill, classifying of powders in vibratory sieves and forming of cylindrical ceramic samples followed by a sintering process at 1500 deg C for 01 hour. The intermediary samples produced in the various steps of the process were characterized by scanning electronic microscope, X-ray diffraction, nitrogen gas adsorption and granulometric analysis. (author)

  12. Investigation of a working fluid for cryogenic energy storage systems

    Science.gov (United States)

    Wojcieszak, P.; Poliński, J.; Chorowski, M.

    2017-12-01

    Cryogenic energy storage (CES) systems are promising alternatives to existing electrical energy storage technologies such as a pumped hydroelectric storage (PHS) or compressed air energy storage (CAES). In CES systems, excess electrical energy is used to liquefy a cryogenic fluid. The liquid can be stored in large cryogenic tanks for a long time. When a demand for the electricity is high, the liquid cryogen is pumped to high pressure and then warmed in a heat exchanger using ambient temperature or an available waste heat source. The vaporized cryogen is then used to drive a turbine and generate the electricity. Most research on cryogenic energy storage focuses on liquid air energy storage, as atmospheric air is widely available and therefore it does not limit a location of the energy storage plant. Nevertheless, CES with other gases as the working fluids can exhibit a higher efficiency. In this research a performance analysis of simple CES systems with several working fluids was performed.

  13. A study of high-energy milling for the production of sintered PrFeB magnets

    Directory of Open Access Journals (Sweden)

    Elio Alberto Périgo

    2007-09-01

    Full Text Available Sintered Pr16Fe76B8 magnets have been produced using the hydrogen decrepitation (HD process and high-energy planetary ball milling. Investigations have been carried out to evaluate the influence of the milling speed and time. The best magnetic properties obtained were Br = (1020 ± 20 mT, µ0iHc = (1420 ± 30 mT and (BHmax/= (200 ± 4 kJm-3, for a magnet prepared with the alloy milled at 200 rpm for 4.5 ks. Magnets prepared from this powder exhibited a superior intrinsic coercivity compared to that of magnets produced using low-energy ball milling. However, the remanence and energy product of the latter were somewhat lower. An important feature was the dramatic reduction in the processing time (about 90%. Microstructural observation have shown that increasing the milling time and keeping constant the rotational mill speed caused an exponential grain size reduction in the sintered magnet. Increasing the milling speed also reduced the grain size and influenced both remanence and intrinsic coercivity.

  14. Laminar Flow Processes of Fluid Energy Carries in Pipe Lines

    Directory of Open Access Journals (Sweden)

    R. I. Еsman

    2012-01-01

    Full Text Available The paper proposes methodology for analysis and calculation of laminar fluid flows in pipes and channels.  Various regimes of fluid motion in pipelines of heat-power units and equipment are considered in the paper.The presented dependencies can be used for practical calculations while transporting energy carriers for various application.

  15. Computational Fluid Dynamics and Building Energy Performance Simulation

    DEFF Research Database (Denmark)

    Nielsen, Peter V.; Tryggvason, Tryggvi

    An interconnection between a building energy performance simulation program and a Computational Fluid Dynamics program (CFD) for room air distribution will be introduced for improvement of the predictions of both the energy consumption and the indoor environment. The building energy performance...

  16. Computational Fluid Dynamics and Building Energy Performance Simulation

    DEFF Research Database (Denmark)

    Nielsen, Peter Vilhelm; Tryggvason, T.

    1998-01-01

    An interconnection between a building energy performance simulation program and a Computational Fluid Dynamics program (CFD) for room air distribution will be introduced for improvement of the predictions of both the energy consumption and the indoor environment. The building energy performance...

  17. Supercritical fluid technology for energy and environmental applications

    CERN Document Server

    Anikeev, Vladimir

    2014-01-01

    Supercritical Fluid Technology for Energy and Environmental Applications covers the fundamental principles involved in the preparation and characterization of supercritical fluids (SCFs) used in the energy production and other environmental applications. Energy production from diversified resources - including renewable materials - using clean processes can be accomplished using technologies like SCFs. This book is focused on critical issues scientists and engineers face in applying SCFs to energy production and environmental protection, the innovative solutions they have found, and the challenges they need to overcome. The book also covers the basics of sub- and supercritical fluids, like the thermodynamics of phase and chemical equilibria, mathematical modeling, and process calculations. A supercritical fluid is any substance at a temperature and pressure above its critical point where distinct liquid and gas phases do not exist. At this state the compound demonstrates unique properties, which can be "fine...

  18. Niobium Carbide-Reinforced Al Matrix Composites Produced by High-Energy Ball Milling

    Science.gov (United States)

    Travessa, Dilermando Nagle; Silva, Marina Judice; Cardoso, Kátia Regina

    2017-06-01

    Aluminum and its alloys are key materials for the transportation industry as they contribute to the development of lightweight structures. The dispersion of hard ceramic particles in the Al soft matrix can lead to a substantial strengthening effect, resulting in composite materials exhibiting interesting mechanical properties and inspiring their technological use in sectors like the automotive and aerospace industries. Powder metallurgy techniques are attractive to design metal matrix composites, achieving a homogeneous distribution of the reinforcement into the metal matrix. In this work, pure aluminum has been reinforced with particles of niobium carbide (NbC), an extremely hard and stable refractory ceramic. Its use as a reinforcing phase in metal matrix composites has not been deeply explored. Composite powders produced after different milling times, with 10 and 20 vol pct of NbC were produced by high-energy ball milling and characterized by scanning electron microscopy and by X-ray diffraction to establish a relationship between the milling time and size, morphology, and distribution of the particles in the composite powder. Subsequently, an Al/10 pct NbC composite powder was hot extruded into cylindrical bars. The strength of the obtained composite bars is comparable to the commercial high-strength, aeronautical-grade aluminum alloys.

  19. Mechanically Induced Graphite-Nanodiamonds-Phase Transformations During High-Energy Ball Milling

    Science.gov (United States)

    El-Eskandarany, M. Sherif

    2017-05-01

    Due to their unusual mechanical, chemical, physical, optical, and biological properties, nearly spherical-like nanodiamonds have received much attention as desirable advanced nanomaterials for use in a wide spectrum of applications. Although, nanodiamonds can be successfully synthesized by several approaches, applications of high temperature and/or high pressure may restrict the real applications of such strategic nanomaterials. Distinct from the current preparation approaches used for nanodiamonds preparation, here we show a new process for preparing ultrafine nanodiamonds (3-5 nm) embedded in a homogeneous amorphous-carbon matrix. Our process started from high-energy ball milling of commercial graphite powders at ambient temperature under normal atmospheric helium gas pressure. The results have demonstrated graphite-single wall carbon nanotubes-amorphous-carbon-nanodiamonds phase transformations carried out through three subsequent stages of ball milling. Based on XRD and RAMAN analyses, the percentage of nanodiamond phase + C60 (crystalline phase) produced by ball milling was approximately 81%, while the amorphous phase amount was 19%. The pressure generated on the powder together the with temperature increase upon the ball-powder-ball collision is responsible for the phase transformations occurring in graphite powders.

  20. Magnetic properties of nanocrystalline pyrrhotite prepared by high-energy milling

    DEFF Research Database (Denmark)

    Balaz, P.; Godocikova, E.; Alacova, A.

    2004-01-01

    The nanocrystalline pyrrhotite was prepared by high-energy milling of lead sulphide with elemental Fe acting as reducing element. X-ray diffractometry, Mossbauer spectroscopy and VSM magnetometry were used to determine the properties of nanocrystalline iron sulphide prepared by the corresponding...... mechanochemical reaction. Pyrrhotite Fe1-xS together with the residual Fe metal were identified by the X-ray diffractometry. The kinetic studies performed by Mossbauer spectroscopy and VSM magnetometry allowed us to follow in more details the progress of the nanocrystalline magnetic phase formation during...

  1. Generation of drugs coated iron nanoparticles through high energy ball milling

    International Nuclear Information System (INIS)

    Radhika Devi, A.; Murty, B. S.; Chelvane, J. A.; Prabhakar, P. K.; Padma Priya, P. V.; Doble, Mukesh

    2014-01-01

    The iron nanoparticles coated with oleic acid and drugs such as folic acid/Amoxicillin were synthesized by high energy ball milling and characterized by X-ray diffraction, Transmission electron microscope, zeta potential, dynamic light scattering, Fourier Transform Infra red (FT-IR) measurements, and thermo gravimetric analysis (TGA). FT-IR and TGA measurements show good adsorption of drugs on oleic acid coated nanoparticles. Magnetic measurements indicate that saturation magnetization is larger for amoxicillin coated particles compared to folic acid coated particles. The biocompatibility of the magnetic nanoparticles prepared was evaluated by in vitro cytotoxicity assay using L929 cells as model cells

  2. Generation of drugs coated iron nanoparticles through high energy ball milling

    Energy Technology Data Exchange (ETDEWEB)

    Radhika Devi, A.; Murty, B. S. [Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai 600036 (India); Chelvane, J. A. [Defence Metallurgical Research Laboratory, Hyderabad 500058 (India); Prabhakar, P. K.; Padma Priya, P. V.; Doble, Mukesh [Department of Biotechnology, Indian Institute of Technology Madras, Chennai 600036 (India)

    2014-03-28

    The iron nanoparticles coated with oleic acid and drugs such as folic acid/Amoxicillin were synthesized by high energy ball milling and characterized by X-ray diffraction, Transmission electron microscope, zeta potential, dynamic light scattering, Fourier Transform Infra red (FT-IR) measurements, and thermo gravimetric analysis (TGA). FT-IR and TGA measurements show good adsorption of drugs on oleic acid coated nanoparticles. Magnetic measurements indicate that saturation magnetization is larger for amoxicillin coated particles compared to folic acid coated particles. The biocompatibility of the magnetic nanoparticles prepared was evaluated by in vitro cytotoxicity assay using L929 cells as model cells.

  3. The determination of radium-226 in uranium ores and mill products by alpha energy spectrometry

    International Nuclear Information System (INIS)

    Zimmerman, J.B.; Armstrong, V.C.

    1975-12-01

    A reliable routine procedure for determining 226 Ra by alpha energy spectrometry is described. Radium is isolated as sulphate from the sample matrix by co-precipitation with a small mass of barium and analysed using a ruggedized silicon surface barrier detector. The method is capable of providing high accuracy over a large 226 Ra concentration range and is applicable to materials such as uranium ores, uranium mill products and effluent streams. Samples resulting from nitric acid leach experiments with Elliot Lake ores were examined using the procedure. The distribution of 223 Ra, 224 Ra and 226 Ra between the leach products, (residue and leach liquor), is discussed. (author)

  4. Dark energy interacting with two fluids

    Energy Technology Data Exchange (ETDEWEB)

    Cruz, Norman [Departamento de Fisica, Facultad de Ciencia, Universidad de Santiago, Casilla 307, Santiago (Chile)], E-mail: ncruz@lauca.usach.cl; Lepe, Samuel [Instituto de Fisica, Facultad de Ciencias Basicas y Matematicas, Universidad Catolica de Valparaiso, Avenida Brasil 2950, Valparaiso (Chile)], E-mail: slepe@ucv.cl; Pena, Francisco [Departamento de Ciencias Fisicas, Facultad de Ingenieria, Ciencias y Administracion, Universidad de La Frontera, Avda. Francisco Salazar 01145, Casilla 54-D Temuco (Chile)], E-mail: fcampos@ufro.cl

    2008-05-29

    A cosmological model of dark energy interacting with dark matter and another general component of the universe is investigated. We found general constraints on these models imposing an accelerated expansion. The same is also studied in the case for holographic dark energy.

  5. New alternative energy pathway for chemical pulp mills: From traditional fibers to methane production.

    Science.gov (United States)

    Rodriguez-Chiang, Lourdes; Vanhatalo, Kari; Llorca, Jordi; Dahl, Olli

    2017-07-01

    Chemical pulp mills have a need to diversify their end-product portfolio due to the current changing bio-economy. In this study, the methane potential of brown, oxygen delignified and bleached pulp were evaluated in order to assess the potential of converting traditional fibers; as well as microcrystalline cellulose and filtrates; to energy. Results showed that high yields (380mL CH 4 /gVS) were achieved with bleached fibers which correlates with the lower presence of lignin. Filtrates from the hydrolysis process on the other hand, had the lowest yields (253mL CH 4 /gVS) due to the high amount of acid and lignin compounds that cause inhibition. Overall, substrates had a biodegradability above 50% which demonstrates that they can be subjected to efficient anaerobic digestion. An energy and cost estimation showed that the energy produced can be translated into a significant profit and that methane production can be a promising new alternative option for chemical pulp mills. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Synthesis and characterization of FePt nanoparticles by high energy ball milling with and without surfactant

    International Nuclear Information System (INIS)

    Velasco, V.; Martinez, A.; Recio, J.; Hernando, A.; Crespo, P.

    2012-01-01

    Highlights: ► Fe and Pt powders in the presence of surfactants don’t alloyed by HEBM technique. ► FePt alloys obtained by dry milling exhibit particle sizes of around 10 μm. ► FePt alloys obtained by dry milling exhibit soft magnetic behavior. ► A thermal treatment induces a phase transformation from FCC to FCT. - Abstract: FePt nanoparticles were prepared by high energy ball milling (HEBM) in two different ways. In the first one, elemental powders were mixed and milled whereas in the second one the milling was performed in the presence of oleyl amine and oleic acid as surfactants and hexane as a solvent. X-ray diffraction shows that when the milling is performed in dry conditions, Fe and Pt are alloyed after 5 h, whereas in the wet milling procedure alloying does not take place. In the first case, the diffraction pattern corresponds to the disordered FCC phase. This behavior is also corroborated by the evolution of the magnetic characteristics. In the case of the alloy obtained in dry conditions, the powder was heat treated in order to induce the transformation to the ordered phase. Coercivities of 2.5 kOe are obtained after 650 °C for 2 h.

  7. Synthesis and characterization of FePt nanoparticles by high energy ball milling with and without surfactant

    Energy Technology Data Exchange (ETDEWEB)

    Velasco, V., E-mail: vvjimeno@fis.ucm.es [Instituto de Magnetismo Aplicado, UCM-ADIF-CSIC, 28230 Las Rozas (Spain); Martinez, A.; Recio, J. [Instituto de Magnetismo Aplicado, UCM-ADIF-CSIC, 28230 Las Rozas (Spain); Hernando, A.; Crespo, P. [Instituto de Magnetismo Aplicado, UCM-ADIF-CSIC, 28230 Las Rozas (Spain); Dpto. de Fisica de Materiales, UCM, 28040 Madrid (Spain)

    2012-09-25

    Highlights: Black-Right-Pointing-Pointer Fe and Pt powders in the presence of surfactants don't alloyed by HEBM technique. Black-Right-Pointing-Pointer FePt alloys obtained by dry milling exhibit particle sizes of around 10 {mu}m. Black-Right-Pointing-Pointer FePt alloys obtained by dry milling exhibit soft magnetic behavior. Black-Right-Pointing-Pointer A thermal treatment induces a phase transformation from FCC to FCT. - Abstract: FePt nanoparticles were prepared by high energy ball milling (HEBM) in two different ways. In the first one, elemental powders were mixed and milled whereas in the second one the milling was performed in the presence of oleyl amine and oleic acid as surfactants and hexane as a solvent. X-ray diffraction shows that when the milling is performed in dry conditions, Fe and Pt are alloyed after 5 h, whereas in the wet milling procedure alloying does not take place. In the first case, the diffraction pattern corresponds to the disordered FCC phase. This behavior is also corroborated by the evolution of the magnetic characteristics. In the case of the alloy obtained in dry conditions, the powder was heat treated in order to induce the transformation to the ordered phase. Coercivities of 2.5 kOe are obtained after 650 Degree-Sign C for 2 h.

  8. 2D Materials with Nanoconfined Fluids for Electrochemical Energy Storage

    Energy Technology Data Exchange (ETDEWEB)

    Augustyn, Veronica [North Carolina State Univ., Raleigh, NC (United States). Dept. of Materials Science and Engineering; Gogotsi, Yury [Drexel Univ., Philadelphia, PA (United States). Dept. of Materials Science and Engineering, A. J. Drexel Nanomaterials Inst.

    2017-10-11

    In the quest to develop energy storage with both high power and high energy densities, and while maintaining high volumetric capacity, recent results show that a variety of 2D and layered materials exhibit rapid kinetics of ion transport by the incorporation of nanoconfined fluids.

  9. Characteristics of Cu–Al2O3 composites of various starting particle size obtained by high-energy milling

    Directory of Open Access Journals (Sweden)

    VIŠESLAVA RAJKOVIĆ

    2009-05-01

    Full Text Available The powder Cu– Al2O3 composites were produced by high-energy milling. Various combinations of particle size and mixtures and approximately constant amount of Al2O3 were used as the starting materials. These powders were separately milled in air for up to 20 h in a planetary ball mill. The copper matrix was reinforced by internal oxidation and mechanical alloying. During the milling, internal oxidation of pre-alloyed Cu-2 mass %-Al powder generated 3.7 mass % Al2O3 nano-sized particles finely dispersed in the copper matrix. The effect of different size of the starting copper and Al2O3 powder particles on the lattice parameter, lattice distortion and grain size, as well as on the size, morphology and microstructure of the Cu– Al2O3 composite powder particles was studied.

  10. Systems and methods for multi-fluid geothermal energy systems

    Science.gov (United States)

    Buscheck, Thomas A.

    2017-09-19

    A method for extracting geothermal energy from a geothermal reservoir formation. A production well is used to extract brine from the reservoir formation. At least one of nitrogen (N.sub.2) and carbon dioxide (CO.sub.2) may be used to form a supplemental working fluid which may be injected into a supplemental working fluid injection well. The supplemental working fluid may be used to augment a pressure of the reservoir formation, to thus drive a flow of the brine out from the reservoir formation.

  11. Preparation of natural pyrite nanoparticles by high energy planetary ball milling as a nanocatalyst for heterogeneous Fenton process

    International Nuclear Information System (INIS)

    Fathinia, Siavash; Fathinia, Mehrangiz; Rahmani, Ali Akbar; Khataee, Alireza

    2015-01-01

    Graphical abstract: - Highlights: • Pyrite nanoparticles were successfully produced by planetary ball milling process. • The physical and chemical properties of pyrite nanoparticles were fully examined. • The degradation of AO7 was notably enhanced by pyrite nanoparticles Fenton system. • The influences of basic operational parameters were investigated using CCD. - Abstract: In the present study pyrite nanoparticles were prepared by high energy mechanical ball milling utilizing a planetary ball mill. Various pyrite samples were produced by changing the milling time from 2 h to 6 h, in the constant milling speed of 320 rpm. X-ray diffraction (XRD), scanning electron microscopy (SEM) linked with energy dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FT-IR) analysis and Brunauer–Emmett–Teller (BET) were performed to explain the characteristics of primary (unmilled) and milled pyrite samples. The average particle size distribution of the produced pyrite during 6 h milling was found to be between 20 nm and 100 nm. The catalytic performance of the different pyrite samples was examined in the heterogeneous Fenton process for degradation of C.I. Acid Orange 7 (AO7) solution. Results showed that the decolorization efficiency of AO7 in the presence of 6 h-milled pyrite sample was the highest. The impact of key parameters on the degradation efficiency of AO7 by pyrite nanoparticles catalyzed Fenton process was modeled using central composite design (CCD). Accordingly, the maximum removal efficiency of 96.30% was achieved at initial AO7 concentration of 16 mg/L, H 2 O 2 concentration of 5 mmol/L, catalyst amount of 0.5 g/L and reaction time of 25 min

  12. Comparative analysis of niobium and vanadium carbide efficiency in the high energy mechanical milling of aluminum bronze alloy

    Directory of Open Access Journals (Sweden)

    Alexandre Nogueira Ottoboni Dias

    Full Text Available Abstract This study aims to analyze the efficiency of niobium and vanadium carbides in the high energy mechanical milling of aluminum bronze alloy. Two series of experiments were made following the same steps for both niobium carbide (NbC and vanadium carbide (VC additions: 30 g of chips were weighed and placed in a stainless steel jar with 3 % of carbide and 1 % of stearic acid for a mass/sphere relationship of 1:10. The milling was realized using a planetary ball mill for 10, 30 and 50 hours in an inert argon atmosphere at 300 rpm. Results shown in laser diffraction indicate a great reduction in the particle sizes of powders when VC is used. For 30 hours milling, D50 values ranged from 1580 µm with NbC to 182.3 µm with VC addition. The D50 values ranged from 251.5 µm with NbC to 52.26 µm with VC addition, for 50 hours milling. The scanning electron microscopy showed that in 10 hours of milling, the energy was not sufficient to achieve the shear of chips in both cases. For 30 hours, it's possible to observe particles with sizes between 100 µm and 800 µm with NbC addition while for the same milling time, with VC it's possible to see particles with different sizes, but with many shapes of fine particulates. For 50 hours milling, particles achieved the smaller sizes between 50 and 200 µm with NbC and ranging from 5 until 50 µm with VC addition.

  13. A top-down assessment of energy, water and land use in uranium mining, milling, and refining

    International Nuclear Information System (INIS)

    Schneider, E.; Carlsen, B.; Tavrides, E.; Hoeven, C. van der; Phathanapirom, U.

    2013-01-01

    Land, water and energy use are key measures of the sustainability of uranium production into the future. As the most attractive, accessible deposits are mined out, future discoveries may prove to be significantly, perhaps unsustainably, more intensive consumers of environmental resources. A number of previous attempts have been made to provide empirical relationships connecting these environmental impact metrics to process variables such as stripping ratio and ore grade. These earlier attempts were often constrained by a lack of real world data and perform poorly when compared against data from modern operations. This paper conditions new empirical models of energy, water and land use in uranium mining, milling, and refining on contemporary data reported by operating mines. It shows that, at present, direct energy use from uranium production represents less than 1% of the electrical energy produced by the once-through fuel cycle. Projections of future energy intensity from uranium production are also possible by coupling the empirical models with estimates of uranium crustal abundance, characteristics of new discoveries, and demand. The projections show that even for the most pessimistic of scenarios considered, by 2100, the direct energy use from uranium production represents less than 3% of the electrical energy produced by the contemporary once-through fuel cycle. - Highlights: • We present environmental impacts of conventional uranium (U) mining and milling technologies. • Impacts include direct energy consumption, land use and water use. • Contemporary mine and mill data is used, updating published estimates that relied on 1970s-era data. • The direct energy used to mine and mill uranium is below 1% of the electrical energy ultimately produced by the uranium. • Even if U demand growth is strong, the direct energy return on investment of U mining and milling will remain well above 1

  14. Potential for reducing paper mill energy use and carbon dioxide emissions through plant-wide energy audits: A case study in China

    International Nuclear Information System (INIS)

    Kong, Lingbo; Price, Lynn; Hasanbeigi, Ali; Liu, Huanbin; Li, Jigeng

    2013-01-01

    Highlights: ► We audited a paper mill in China to reduce its energy use and CO 2 emissions. ► The energy use and CO 2 emissions of the mill and each paper machine are presented. ► The energy saving potential for the paper machine is estimated at 8–37%. ► The energy saving potential is 967.8 TJ, equal to 14.4% of the mill’s energy use. ► The CO 2 reduction potential is 93,453 tonnes CO 2 for the studied paper mill. -- Abstract: The pulp and paper industry is one of the most energy-intensive industries worldwide. In 2007, it accounted for 5% of total global industrial energy consumption and 2% of direct industrial carbon dioxide (CO 2 ) emissions. An energy audit is a primary step toward improving energy efficiency at the facility level. This paper describes a plant-wide energy audit aimed at identifying energy conservation and CO 2 mitigation opportunities at a paper mill in Guangdong province, China. We describe the energy audit methods, relevant Chinese standards, methods of calculating energy and carbon indicators, baseline energy consumption and CO 2 emissions of the audited paper mill, and nine energy-efficiency improvement opportunities identified by the audit. For each of the nine options, we evaluate the energy conservation and associated CO 2 mitigation potential. The total technical energy conservation potential for these nine opportunities is 967.8 terajoules (TJ), and the total CO 2 mitigation potential is equal to 93,453 tonnes CO 2 annually, representing 14.4% and 14.7%, respectively, of the mill’s total energy consumption and CO 2 emissions during the audit period.

  15. Multi-fluid renewable geo-energy systems and methods

    Science.gov (United States)

    Buscheck, Thomas A.

    2017-08-22

    A geo-energy production method for extracting thermal energy from a reservoir formation. A production well extracts brine from the reservoir formation. A plurality of working fluid injection ("WFI") wells may be arranged proximate to the production well to at least partially circumscribe the production well. A plurality of brine production ("BP") wells may be arranged in a vicinity of the WFI wells to at least partially circumscribe the WFI wells. A working fluid is injected into the WFI wells to help drive a flow of the brine up through the production and BP wells, together with at least a portion of the injected working fluid. Parasitic-load time-shifting and to storing of excess solar thermal energy may also be performed.

  16. Grain growth of CuO nanocrystal activated by high energy ball milling

    International Nuclear Information System (INIS)

    Bianchi, A.E.; Stewart, S.J.; Punte, G.; Vina, R.; Plivelic, T.S.; Torriani, I.L.

    2007-01-01

    X-ray Diffraction (XRD), small-angle X-ray scattering, scanning electron microscopy and energy dispersive X-ray Analysis were used to investigate the effect of controlled high energy ball milling (HEBM) on the average volume weighted crystallite size, V and weighted average microstrain, , of nanostructures of CuO prepared by solid state reaction. The starting material, S 0 , consists of almost strain free nanocrystals of monoclinic CuO with V ∼ 20nm , as determined by XRD data Rietveld analysis. It was found that after an initial decrease of V and increase of , the values of these parameters go through a steady-state stage followed by an increase of an order of magnitude in after a period of only 120 m of HEBM. According to the results here presented, the presence of small amounts of contaminants in the starting material can have an influence on the kinetics of crystal growth in HEBM CuO

  17. High Density Thermal Energy Storage with Supercritical Fluids

    Science.gov (United States)

    Ganapathi, Gani B.; Wirz, Richard

    2012-01-01

    A novel approach to storing thermal energy with supercritical fluids is being investigated, which if successful, promises to transform the way thermal energy is captured and utilized. The use of supercritical fluids allows cost-affordable high-density storage with a combination of latent heat and sensible heat in the two-phase as well as the supercritical state. This technology will enhance penetration of several thermal power generation applications and high temperature water for commercial use if the overall cost of the technology can be demonstrated to be lower than the current state-of-the-art molten salt using sodium nitrate and potassium nitrate eutectic mixtures.

  18. High energy behavior of a six-point R-current correlator in N=4 supersymmetric Yang-Mills theory

    Energy Technology Data Exchange (ETDEWEB)

    Bartels, Jochen; Hentschinski, Martin; Mischler, Anna-Maria [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Ewerz, Carlo [Heidelberg Univ. (Germany). Inst. fuer Theoretische Physik; GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany). ExtreMe Matter Institute EMMI; Bielefeld Univ. (Germany). Fakultaet fuer Physik; European Centre for Theoretical Studies in Nuclear Physics and Related Areas (ECT), Villazzano (Italy)

    2009-12-15

    We study the high energy limit of a six-point R-current correlator in N=4 supersymmetric Yang-Mills theory for finite N{sub c}. We make use of the framework of perturbative resummation of large logarithms of the energy. More specifically, we apply the (extended) generalized leading logarithmic approximation. We find that the same conformally invariant two-to-four gluon vertex occurs as in non-supersymmetric Yang-Mills theory. As a new feature we find a direct coupling of the four-gluon t-channel state to the R-current impact factor. (orig.)

  19. High energy behavior of a six-point R-current correlator in N=4 supersymmetric Yang-Mills theory

    International Nuclear Information System (INIS)

    Bartels, Jochen; Hentschinski, Martin; Mischler, Anna-Maria

    2009-12-01

    We study the high energy limit of a six-point R-current correlator in N=4 supersymmetric Yang-Mills theory for finite N c . We make use of the framework of perturbative resummation of large logarithms of the energy. More specifically, we apply the (extended) generalized leading logarithmic approximation. We find that the same conformally invariant two-to-four gluon vertex occurs as in non-supersymmetric Yang-Mills theory. As a new feature we find a direct coupling of the four-gluon t-channel state to the R-current impact factor. (orig.)

  20. Synthesis of the Mg2Ni alloy prepared by mechanical alloying using a high energy ball mill

    International Nuclear Information System (INIS)

    Iturbe G, J. L.; Lopez M, B. E.; Garcia N, M. R.

    2010-01-01

    Mg 2 Ni was synthesized by a solid state reaction from the constituent elemental powder mixtures via mechanical alloying. The mixture was ball milled for 10 h at room temperature in an argon atmosphere. The high energy ball mill used here was fabricated at ININ. A hardened steel vial and three steel balls of 12.7 mm in diameter were used for milling. The ball to powder weight ratio was 10:1. A small amount of powder was removed at regular intervals to monitor the structural changes. All the steps were performed in a little lucite glove box under argon gas, this glove box was also constructed in our Institute. The structural evolution during milling was characterized by X-ray diffraction and scanning electron microscopy techniques. The hydrogen reaction was carried out in a micro-reactor under controlled conditions of pressure and temperature. The hydrogen storage properties of mechanically milled powders were evaluated by using a thermogravimetric analysis system. Although homogeneous refining and alloying take place efficiently by repeated forging, the process time can be reduced to one fiftieth of the time necessary for conventional mechanical milling and attrition. (Author)

  1. Synthesis of the Mg{sub 2}Ni alloy prepared by mechanical alloying using a high energy ball mill

    Energy Technology Data Exchange (ETDEWEB)

    Iturbe G, J. L.; Lopez M, B. E. [ININ, Departamento de Quimica, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Garcia N, M. R., E-mail: joseluis.iturbe@inin.gob.m [UNAM, Facultad de Estudios Superiores Zaragoza, Batalla 5 de Mayo s/n, Esq. Fuerte de Loreto, Col. Ejercito de Oriente, 09230 Mexico D. F. (Mexico)

    2010-07-01

    Mg{sub 2}Ni was synthesized by a solid state reaction from the constituent elemental powder mixtures via mechanical alloying. The mixture was ball milled for 10 h at room temperature in an argon atmosphere. The high energy ball mill used here was fabricated at ININ. A hardened steel vial and three steel balls of 12.7 mm in diameter were used for milling. The ball to powder weight ratio was 10:1. A small amount of powder was removed at regular intervals to monitor the structural changes. All the steps were performed in a little lucite glove box under argon gas, this glove box was also constructed in our Institute. The structural evolution during milling was characterized by X-ray diffraction and scanning electron microscopy techniques. The hydrogen reaction was carried out in a micro-reactor under controlled conditions of pressure and temperature. The hydrogen storage properties of mechanically milled powders were evaluated by using a thermogravimetric analysis system. Although homogeneous refining and alloying take place efficiently by repeated forging, the process time can be reduced to one fiftieth of the time necessary for conventional mechanical milling and attrition. (Author)

  2. Characterization of Printed Circuit Boards for Metal and Energy Recovery after Milling and Mechanical Separation

    Directory of Open Access Journals (Sweden)

    Waldir A. Bizzo

    2014-06-01

    Full Text Available The proper disposal of electrical and electronic waste is currently a concern of researchers and environmental managers not only because of the large volume of such waste generated, but also because of the heavy metals and toxic substances it contains. This study analyzed printed circuit boards (PCBs from discarded computers to determine their metal content and characterized them as solid waste and fuel. The analysis showed that PCBs consist of approximately 26% metal, made up mainly of copper, lead, aluminum, iron and tin, as well as other heavy metals such as cadmium and nickel. Comparison with the results of other studies indicated that the concentration of precious metals (gold and silver has declined over time. Analysis of the leachate revealed high concentrations of cadmium and lead, giving the residue the characteristics of hazardous waste. After milling the PCBs, we found that larger amounts of metal were concentrated in smaller fractions, while the lightest fraction, obtained by density separation, had a gross calorific value of approximately 11 MJ/kg, although with a high ash content. Milling followed by density separation proved potentially useful for recovery of metals and energy-rich fractions.

  3. Fabrication of Al2O3–20 vol.% Al nanocomposite powders using high energy milling and their sinterability

    International Nuclear Information System (INIS)

    Zawrah, M.F.; Abdel-kader, H.; Elbaly, N.E.

    2012-01-01

    Highlights: ► Al 2 O 3 /Al nanocomposite powders were prepared via high energy ball milling. After 20 h milling, the size of Al 2 O 3 –20 vol.% Al nanocomposite particles was in the range of 23–29 nm. A uniform distribution of nanosized Al reinforcement throughout the Al 2 O 3 matrix, coating the particles was successfully obtained. ► There was no any sign of phase changes during the milling. A competition between the cold welding mechanism and the fracturing mechanism were found during milling and finally the above two mechanisms reached an equilibrium. ► The highest value of relative density was obtained for the sintered bodies at 1500 °C. ► The harness of the sintered composite was decreased while the fracture toughness was improved after addition Al into alumina. -- Abstract: In this study, alumina-based matrix nanocomposite powders reinforced with Al particles were fabricated and investigated. The sinterability of the prepared nanocomposite powder at different firing temperature was also conducted. Their mechanical properties in terms of hardness and toughness were tested. Alumina and aluminum powder mixtures were milled in a planetary ball mill for various times up to 30 h in order to produce Al 2 O 3 –20% Al nanocomposite. The phase composition, morphological and microstructural changes during mechanical milling of the nanocomposite particles were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscope (SEM) techniques, respectively. The crystallite size and internal strain were evaluated by XRD patterns using Scherrer methods. A uniform distribution of the Al reinforcement in the Al 2 O 3 matrix was successfully obtained after milling the powders. The results revealed that there was no any sign of phase changes during the milling. The crystal size decreased with the prolongation of milling times, while the internal strain increased. A simple model is presented to illustrate the mechanical

  4. Synthesis and characterization of high volume fraction Al-Al2O3 nanocomposite powders by high-energy milling

    International Nuclear Information System (INIS)

    Prabhu, B.; Suryanarayana, C.; An, L.; Vaidyanathan, R.

    2006-01-01

    Al-Al 2 O 3 metal matrix composite (MMC) powders with volume fractions of 20, 30, and 50% Al 2 O 3 were synthesized by high-energy milling of the blended component powders. The particle sizes of Al 2 O 3 studied were 50 nm, 150 nm, and 5 μm. A uniform distribution of the Al 2 O 3 reinforcement in the Al matrix was successfully obtained after milling the powders for a period of 20 h at a ball-to-powder ratio of 10:1 in a SPEX mill. The uniform distribution of Al 2 O 3 in the Al matrix was confirmed by characterizing these nanocomposite powders by scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), X-ray mapping, and X-ray diffraction (XRD) techniques

  5. Bluff Body Fluid Interactions Modelling for Micro Energy Harvesting Application

    International Nuclear Information System (INIS)

    Bhuyan, M S; Majlis, B Y; Islam, S; Othman, M; Ali, Sawal H Md; Kalaivani, C

    2013-01-01

    In this paper, we have presented a MEMS-based piezoelectric fluid-flow based micro energy harvester. The design and modelling of the energy harvester structure was based on a piezoelectric cantilever affixed to a bluff-body. In a cross fluid flow, pressure in the flow channel, in the wake of the bluff body, fluctuates with the same frequency as the pressure variation caused by the Kármán Vortex Street. This fluctuation of pressure in the flow channel causes the piezoelectric cantilever, trailing the bluff-body, to vibrate in a direction normal to the fluid flow direction. COMSOL finite element analysis software are used for the evaluation of various mechanical analysis of the micro energy harvester structure like, physical the Stress and Strain state in the cantilever structures, Eigen frequency Analysis, Transient analysis to demonstrate the feasibility of the design. Detailed steps of modelling and simulation results of the uniform cantilever were explained. The results confirm the probability of the fluid flow based MEMS energy harvester.

  6. Twisted tubular photobioreactor fluid dynamics evaluation for energy consumption minimization

    NARCIS (Netherlands)

    Gómez-Pérez, C.A.; Espinosa Oviedo, J.J.; Montenegro Ruiz, L.C.; Boxtel, van A.J.B.

    2017-01-01

    This paper discusses a new tubular PhotoBioReactor (PBR) called twisted tubular PBR. The geometry of a twisted tubular PBR induces swirl mixing to guarantee good exposure of microalgae to Light-Dark (LD) cycles and to the nutrients and dissolved CO 2 . The paper analyses the energy uptake for fluid

  7. Compressed Air System Optimization Saves Energy and Improves Production at a Textile Manufacturing Mill (Peerless Division, Thomaston Mills, Inc.): Office of Industrial Technologies (OIT) BestPractices Technical Case Study

    Energy Technology Data Exchange (ETDEWEB)

    Wogsland, J.

    2001-06-18

    This case study is one in a series on industrial firms who are implementing energy efficient technologies and system improvements into their manufacturing processes. This case study documents the activities, savings, and lessons learned on the textile manufacturing mill project.

  8. Study of the aluminothermic reduction of niobium pentoxide through thermal analysis experiments and high energy milling processing

    Directory of Open Access Journals (Sweden)

    Claudio Parra De Lazzari

    2007-06-01

    Full Text Available Aluminothermic reduction of niobium pentoxide was studied through thermal analysis techniques such as differential thermal analysis (DTA and thermogravimetry (TG as well as through high energy milling processing. Reactants mixtures were composed by powders of Nb2O5 and Al. In the case of DTA-TG experiments, different molar ratios Nb2O5:Al were heated in a dynamic atmosphere of synthetic air under controlled conditions. The high energy milling runs were carried out via SPEX vibratory mill under argon atmosphere and with milling power equal to 7:1 (ratio of mass of balls to mass of mixture with 10 pct excess of Al over the stoichiometric mass of aluminum necessary. In both kinds of experiments, X ray diffraction was used in order to identify the products of reaction. From DTA-TG experiments, it was possible to determine the experimental value of the enthalpy change (-595.9 kJ.mol-1, which is near to the theoretical one. From the milling experiments, it was possible to verify the possibility of the occurance of aluminothermic reducion of niobium pentoxide via this kind of processing.

  9. Energy-momentum tensor on the lattice: Nonperturbative renormalization in Yang-Mills theory

    Science.gov (United States)

    Giusti, Leonardo; Pepe, Michele

    2015-06-01

    We construct an energy-momentum tensor on the lattice which satisfies the appropriate Ward identities (WIs) and has the right trace anomaly in the continuum limit. It is defined by imposing suitable WIs associated to the Poincaré invariance of the continuum theory. These relations come forth when the length of the box in the temporal direction is finite, and they take a particularly simple form if the coordinate and the periodicity axes are not aligned. We implement the method for the SU(3) Yang-Mills theory discretized with the standard Wilson action in the presence of shifted boundary conditions in the (short) temporal direction. By carrying out extensive numerical simulations, the renormalization constants of the traceless components of the tensor are determined with a precision of roughly half a percent for values of the bare coupling constant in the range 0 ≤g02≤1 .

  10. Preparation of bismuth telluride based thermoelectric nanomaterials via low-energy ball milling and their property characterizations

    Science.gov (United States)

    Robinson, Christopher A.

    Thermoelectric materials are able to convert energy between heat and electricity with no moving parts, making them very appealing for power generation purposes. This is particularly appealing since many forms of energy generation lose energy to waste heat. The Livermore National Laboratory estimates that up to 55% of the energy created in traditional power plants is lost through heat generation [1]. As greenhouse gas emissions become a more important issue, large sources of waste like this will need to be harnessed. Adoption of these materials has been limited due to the cost and efficiency of current technology. Bismuth telluride based alloys have a dimensionless figure of merit, a measure of efficiency, near one at room temperature, which makes it the best current material. In order to compete with other forms of energy generation, this needs to be increased to three or higher [2]. Recently, improvements in performance have come in the form of random nanostructured materials [3]. Bulk bismuth telluride is subjected to particle size reduction via high-energy ball milling in order to scatter phonons between grains. This reduces the lattice thermal conductivity which in turn increases the performance of the material. In this work, we investigate the use of low-energy ball milling as a method of creating nanoparticles of n-type and p-type Bi2Te3 alloys for thermoelectric applications. Optimization of parameters such as milling containers, milling media, contamination and milling time has resulted in creating 15nm particles of bismuth telluride alloys. After creating solid pellets of the resulting powders via hot pressing, the material's thermal and electrical conductivities as well as Seebeck coefficients were measured. The ZT of n-type Bi2Te2.7Se3 created using this method is 0.32, while the p-type Bi0.5Sb1.5Te3 exhibits a higher ZT of 1.24, both at room temperature.

  11. Negative energy modes and gravitational instability of interpenetrating fluids

    Energy Technology Data Exchange (ETDEWEB)

    Casti, A.R.R.; Spiegel, E.A. [Columbia Univ., New York, NY (United States); Morrison, P.J. [Univ. of Texas, Austin, TX (United States)

    1998-09-01

    The authors study the longitudinal instabilities of two interpenetrating fluids interacting only through gravity. When one of the constituents is of relatively low density, it is possible to have a band of unstable wave numbers well separated from those involved in the usual Jeans instability. If the initial streaming is large enough, and there is no linear instability, the indefinite sign of the free energy has the possible consequence of explosive interactions between positive and negative energy modes in the nonlinear regime. The effect of dissipation on the negative energy modes is also examined.

  12. Rapid calculation of partition functions and free energies of fluids.

    Science.gov (United States)

    Do, Hainam; Hirst, Jonathan D; Wheatley, Richard J

    2011-11-07

    The partition function (Q) is a central quantity in statistical mechanics. All the thermodynamic properties can be derived from it. Here we show how the partition function of fluids can be calculated directly from simulations; this allows us to obtain the Helmholtz free energy (F) via F = -k(B)T ln Q. In our approach, we divide the density of states, assigning half of the configurations found in a simulation to a high-energy partition and half to a low-energy partition. By recursively dividing the low-energy partition into halves, we map out the complete density of states for a continuous system. The result allows free energy to be calculated directly as a function of temperature. We illustrate our method in the context of the free energy of water.

  13. Low energy milling method, low crystallinity alloy, and negative electrode composition

    Science.gov (United States)

    Le, Dihn B; Obrovac, Mark N; Kube, Robert Y; Landucci, James R

    2012-10-16

    A method of making nanostructured alloy particles includes milling a millbase in a pebble mill containing milling media. The millbase comprises: (i) silicon, and (ii) at least one of carbon or a transition metal, and wherein the nanostructured alloy particles are substantially free of crystalline domains greater than 50 nanometers in size. A method of making a negative electrode composition for a lithium ion battery including the nanostructured alloy particles is also disclosed.

  14. Fabrication mechanism of FeSe superconductors with high-energy ball milling aided sintering process

    International Nuclear Information System (INIS)

    Zhang, Shengnan; Liu, Jixing; Feng, Jianqing; Wang, Yao; Ma, Xiaobo; Li, Chengshan; Zhang, Pingxiang

    2015-01-01

    FeSe Superconducting bulks with high content of superconducting PbO-type β-FeSe phase were prepared with high-energy ball milling (HEBM) aided sintering process. During this process, precursor powders with certain Fe/Se ratio were ball milled first then sintered. The influences of HEBM process as well as initial Fe/Se ratio on the phase evolution process were systematically discussed. With HEBM process and proper initial Fe/Se ratio, the formation of non-superconducting hexagonal δ-FeSe phase were effectively avoided. FeSe bulk with the critical temperature of 9.0 K was obtained through a simple one-step sintering process with lower sintering temperature. Meanwhile, the phase evolution mechanism of the HEBM precursor powders during sintering was deduced based on both the thermodynamic analysis and step-by-step sintering results. The key function of the HEBM process was to provide a high uniformity of chemical composition distribution, thus to successfully avoide the formation of intermediate product during sintering, including FeSe 2 and Fe 7 Se 8 . Therefore, the fundamental principal for the synthesis of FeSe superconductors were concluded as: HEBM aided sintering process, with the sintering temperature of >635 °C and a slow cooling process. - Highlights: • A novel synthesis technique was developed for FeSe based superconductors. • FeSe bulks with high Tc and high β-FeSe phase content has been obtained. • Phase evolution process for the HEBM aided sintering process was proposed

  15. Effect of the milling energy on the production and thermal stability of amorphous Mg{sub 50}Ni{sub 50}

    Energy Technology Data Exchange (ETDEWEB)

    Guzman, D. [Departamento de Ingenieria Metalurgica, Facultad de Ingenieria, Universidad de Santiago de Chile, Av. Lib. Bernardo O' Higgins 3363, Santiago (Chile); Ordonez, S. [Departamento de Ingenieria Metalurgica, Facultad de Ingenieria, Universidad de Santiago de Chile, Av. Lib. Bernardo O' Higgins 3363, Santiago (Chile)], E-mail: sordonez@usach.cl; Serafini, D. [Departamento de Fisica, Facultad de Ciencias, Universidad de Santiago de Chile and Center for Interdisciplinary Research in Materials, CIMAT, Av. Lib. Bernardo O' Higgins 3363, Santiago (Chile); Rojas, P. [Instituto de Fisica, Facultad de Ciencias Basicas y Matematicas, Pontificia Universidad Catolica de Valparaiso, Av. Brasil 2950, Valparaiso (Chile); Bustos, O. [Departamento de Ingenieria Metalurgica, Facultad de Ingenieria, Universidad de Santiago de Chile, Av. Lib. Bernardo O' Higgins 3363, Santiago (Chile)

    2009-03-05

    The effect of milling energy on the amorphisation process and subsequent thermal crystallization of Mg{sub 50}Ni{sub 50} was investigated. The amorphous Mg{sub 50}Ni{sub 50} was produced using a planetary mill (medium energy) with a ball to material weight ratio of 13:1, and a SPEX mill (high energy) with a ball to material weight ratio of 20:1. The results obtained by means of X-ray diffraction showed that it is possible to obtain an amorphous Mg{sub 50}Ni{sub 50} alloy, through both milling processes, starting of Ni powders and Mg turnings. However, the amorphisation process requires more time in the planetary mill (80-90 h) than in the SPEX mill (15-20 h), due to the difference in energy level and milling mechanism between these mills. The phase evolution during the amorphisation process is practically independent of the mill energy. In this way, it was observed that the mill conditions promoted an extensive refinement of the microstructure during the first hours of milling. The defects produced during this time led to the amorphisation of part of the system. This amorphous precursor suffers a mechanically induced crystallization into Mg{sub 2}Ni, which is subsequently destabilized into amorphous Mg{sub 50}Ni{sub 50}. Based on the results obtained, it is proposed that the formation of amorphous precursor during mechanical milling of Mg and Ni is a characteristic of the Mg-Ni system, over a wide composition range, rather than of a particular composition. In relation to the thermal crystallization of the amorphous produced, the results of the differential thermal analysis applied to the amorphous samples showed that the formation enthalpy for both amorphous is the same, however, the amorphous produced in a planetary mill presented higher crystallization temperatures and apparent activation energies than the amorphous produced in a SPEX mill. The last behavior would be related with iron contamination coming from the erosion of the milling media. Finally, it is

  16. Structure and high temperature frictional behavior of a coal pitch-derived carbonaceous mesophase (CM) treated by high-energy ball milling

    International Nuclear Information System (INIS)

    Zhang Ruijun; Liu Riping; Cui Xiaohao

    2007-01-01

    A coal tar pitch-derived carbonaceous mesophase (CM) was treated in a high-energy ball mill apparatus. The structures for the raw and the as-milled CMs were characterized by X-ray diffraction and laser-Raman spectroscopic techniques, and the frictional behaviors for the CMs were investigated by using a SRV high temperature friction and wear tester. The results have shown that, high-energy ball milling leads to a drop in the crystallinity of the CMs and a decrease in the size of graphite planar micro-crystals, implying a higher structural amorphism caused by the high-energy ball milling. In addition, the CMs display a high temperature lubrication effect. High-energy ball milling is supposed to be beneficial to the graphitization of the CMs induced by friction mechanical action, and, therefore, facilitate the high temperature lubrication effect to some extent

  17. Surfactant Removal Study for Nano-Scale SmCo5 Powder Prepared by High Energy Ball Milling (Postprint)

    Science.gov (United States)

    2014-04-01

    determine magnetic coercivity , remanence , and maximum energy product . III. RESULTS AND DISCUSSION SEM imaging of the as-milled and heat treated pow- ders... remanence and max- imum energy product . Ar pressure is highly effective in preventing oxygen access to the powder and avoiding alloy oxidation...slight variation in measured remanence and coercivity between samples is expected due to some inconsistency in sample preparation steps we assumed M(H

  18. Split energy cascade in turbulent thin fluid layers

    Science.gov (United States)

    Musacchio, Stefano; Boffetta, Guido

    2017-11-01

    We discuss the phenomenology of the split energy cascade in a three-dimensional thin fluid layer by means of high resolution numerical simulations of the Navier-Stokes equations. We observe the presence of both an inverse energy cascade at large scales, as predicted for two-dimensional turbulence, and a direct energy cascade at small scales, as in three-dimensional turbulence. The inverse energy cascade is associated with a direct cascade of enstrophy in the intermediate range of scales. Notably, we find that the inverse cascade of energy in this system is not a purely 2D phenomenon, as the coupling with the 3D velocity field is necessary to guarantee the constancy of fluxes.

  19. Neutron radigoraphy of fluid flow for geothermal energy research

    Energy Technology Data Exchange (ETDEWEB)

    Bingham, Philip R [ORNL; Polsky, Yarom [ORNL; Anovitz, Lawrence {Larry} M [ORNL; Carmichael, Justin R [ORNL; Bilheux, Hassina Z [ORNL; Hussey, Dan [NIST Center for Neutron Research (NCRN), Gaithersburg, MD; Jacobson, David [National Institute of Standards and Technology (NIST)

    2015-01-01

    Enhanced geothermal systems seek to expand the potential for geothermal energy by engineering heat exchange systems within the earth. A neutron radiography imaging method has been developed for the study of fluid flow through rock under environmental conditions found in enhanced geothermal energy systems. For this method, a pressure vessel suitable for neutron radiography was designed and fabricated, modifications to imaging instrument setups were tested, multiple contrast agents were tested, and algorithms developed for tracking of flow. The method has shown success for tracking of single phase flow through a manufactured crack in a 3.81 cm (1.5 inch) diameter core within a pressure vessel capable of confinement up to 69 MPa (10,000 psi) using a particle tracking approach with bubbles of fluorocarbon-based fluid as the “particles” and imaging with 10 ms exposures.

  20. Cosmological effects of a class of fluid dark energy models

    International Nuclear Information System (INIS)

    Carturan, Daniela; Finelli, Fabio

    2003-01-01

    We study the impact of a generalized Chaplygin gas as a candidate for dark energy on density perturbations and on cosmic microwave background (CMB) anisotropies. The generalized Chaplygin gas is a fluid component with an exotic equation of state p=-A/ρ α (a polytropic gas with negative constant and exponent). Such a component interpolates in time between dust and a cosmological constant, with an intermediate behavior as p=A 1/(1+α) +αρ. Perturbations of this fluid are stable on small scales but behave in a very different way with respect to standard quintessence. Moreover, a generalized Chaplygin gas could also represent an archetypal example of the phenomenological unified models of dark energy and dark matter. The results presented here show how CMB anisotropies and density perturbations in this class of models differ from those of a cold dark matter model with a cosmological constant

  1. Pyrolysis of fibre residues with plastic contamination from a paper recycling mill: Energy recoveries

    International Nuclear Information System (INIS)

    Brown, Logan Jeremy; Collard, François-Xavier; Görgens, Johann

    2017-01-01

    Highlights: • Pyrolysis of fibre-plastics residues from paper recycling mill into fuel products. • Product with remarkable energy content up to 42.8 MJ/kg. • Influence of temperature on the product yields and fuel properties. • Effect of plastic composition on product properties. - Abstract: Pyrolysis is a promising technology for the production of marketable energy products from waste mixtures, as it decomposes heterogeneous material into homogenous fuel products. This research assessed the ability of slow pyrolysis to convert three waste streams, composed of fibre residues contaminated with different plastic mixtures, into char and tarry phase products at three different temperatures (300, 425 and 550 °C). The products were characterised in terms of mass yield, higher heating value (HHV) and gross energy conversion (EC). Significant amounts of hydrocarbon plastics in the feed materials increased the calorific values of the char (up to 32.9 MJ/kg) and tarry phase (up to 42.8 MJ/kg) products, comparable to high volatile bituminous A coal and diesel respectively. For all three waste streams converted at 300 °C, the majority of the energy in the feedstock was recovered in the char product (>80%), while deoxygenation of fibre component resulted in char with increased calorific value (up to 31.6 MJ/kg) being produced. Pyrolysis at 425 °C for two of the waste streams containing significant amounts of plastic produced both a valuable char and tarry phase, which resulted in an EC greater than 74%. Full conversion of plastic at 550 °C increased the tarry phase yield but dramatically decreased the char HHV. The influence of temperature on product yield and HHV was discussed based on the pyrolysis mechanisms and in relation to the plastic composition of the waste streams.

  2. Formation of Nanoscale Metallic Glassy Particle Reinforced Al-Based Composite Powders by High-Energy Milling

    Directory of Open Access Journals (Sweden)

    Weiwen Zhang

    2017-10-01

    Full Text Available The initial microstructure and mechanical properties of composite powders have a vital role in determining the microstructure and mechanical properties of the subsequent consolidated bulk composites. In this work, Al-based matrix composite powders with a dense and uniform distribution of metallic glass nanoparticles were obtained by high-energy milling. The results show that high-energy milling is an effective method for varying the microstructure and mechanical properties of the composite powders, thereby offering the ability to control the final microstructure and properties of the bulk composites. It was found that the composite powders show a deformed layer combined with an undeformed core after milling. The reinforcements, metallic glass microparticles, are fractured into dense distributed nanoparticles in the deformed layer, owing to the severe plastic deformation, while in the undeformed core, the metallic glass microparticles are maintained. Therefore, a bimodal structure was obtained, showing a mechanical bimodal structure that has much higher hardness in the outer layer than the center core. The hardness of the composite particles increases significantly with increasing milling time, due to dispersion strengthening and work hardening.

  3. Energy transport in cooling device by magnetic fluid

    Science.gov (United States)

    Yamaguchi, Hiroshi; Iwamoto, Yuhiro

    2017-06-01

    Temperature sensitive magnetic fluid has a great potential with high performance heat transport ability as well as long distance energy (heat) transporting. In the present study experimental set-up was newly designed and constructed in order to measure basic heat transport characteristics under various magnetic field conditions. Angular dependence for the device (heat transfer section) was also taken into consideration for a sake of practical applications. The energy transfer characteristic (heat transport capability) in the magnetically-driven heat transport (cooling) device using the binary TSMF was fully investigated with the set-up. The obtained results indicate that boiling of the organic mixture (before the magnetic fluid itself reaching boiling point) effectively enhances the heat transfer as well as boosting the flow to circulate in the closed loop by itself. A long-distance heat transport of 5 m is experimentally confirmed, transferring the thermal energy of 35.8 W, even when the device (circulation loop) is horizontally placed. The highlighted results reveal that the proposed cooling device is innovative in a sense of transporting substantial amount of thermal energy (heat) as well as a long distance heat transport. The development of the magnetically-driven heat transport device has a great potential to be replaced for the conventional heat pipe in application of thermal engineering.

  4. Synthesizing Zno Nanoparticles by High-Energy Milling and Investigating Their Antimicrobial Effect

    Directory of Open Access Journals (Sweden)

    N Mohammadi

    2015-07-01

    Results: The study results demonstrated that size of the synthesized nanoparticles was within the range of 20 -90 nm and their morphology was reported as nanorod and nanoparticles with multifaceted cross-section. An increase in the density of nanoparticles resulted in a rise in the antimicrobial effect. Moreover, Staphylococcus aureus bacteria inhibition zone was 3±0.5 and 7±0.5 mm respectively at the density of 6 and 10 mM. The MIC and MBC of ZnO nanoparticles provided for Staphylococcus aureus were observed 3±3 and 2.5±0 mg/ml, whereas they were reported 7.5±0 and 8±0 mg/ml for Escherichia coli bacteria. Conclusion: The findings of the present study revealed that ZnO nanomaterials could be synthesized by applying high-energy milling on micron-scaled ZnO particles. In addition, they can be utilized in food packaging and preservation process.

  5. Borehole temperatures reveal a changed energy budget at Mill Island, East Antarctica, over recent decades

    Directory of Open Access Journals (Sweden)

    J. L. Roberts

    2013-02-01

    Full Text Available A borehole temperature record from the Mill Island (East Antarctica icecap reveals a large surface warming signal manifested as a 0.75 K temperature difference over the approximate 100 m depth in the zone of zero annual amplitude below the seasonally varying zone. The temperature profile shows a break in gradient around 49 m depth, which we model with inverse numerical simulations, indicating that surface warming started around the austral summer of 1980/81 AD ±5 yr. This warming of approximately 0.37 K per decade is consistent with trends seen in both instrumental and other reconstructions for Antarctica and, therefore, suggests that regional- rather than local-scale processes are largely responsible. Alteration of the surface energy budget arising from changes in radiation balances due to local cloud, the amount of liquid deposition and local air temperatures associated with altered air/sea exchanges also potentially plays a role at this location due to the proximity of the Shackleton Ice Shelf and sea-ice zone.

  6. Grinding energy and physical properties of chopped and hammer-milled barley, wheat, oat, and canola straws

    Energy Technology Data Exchange (ETDEWEB)

    J.S. Tumuluru; L.G. Tabil; Y. Song; K.L. Iroba; V. Meda

    2014-01-01

    In the present study, specific energy for grinding and physical properties of wheat, canola, oat and barley straw grinds were investigated. The initial moisture content of the straw was about 0.13–0.15 (fraction total mass basis). Particle size reduction experiments were conducted in two stages: (1) a chopper without a screen, and (2) a hammer mill using three screen sizes (19.05, 25.4, and 31.75 mm). The lowest grinding energy (1.96 and 2.91 kWh t-1) was recorded for canola straw using a chopper and hammer mill with 19.05-mm screen size, whereas the highest (3.15 and 8.05 kWh t-1) was recorded for barley and oat straws. The physical properties (geometric mean particle diameter, bulk, tapped and particle density, and porosity) of the chopped and hammer-milled wheat, barley, canola, and oat straw grinds measured were in the range of 0.98–4.22 mm, 36–80 kg m-3, 49–119 kg m-3, 600–1220 kg m-3, and 0.9–0.96, respectively. The average mean particle diameter was highest for the chopped wheat straw (4.22-mm) and lowest for the canola grind (0.98-mm). The canola grinds produced using the hammer mill (19.05-mm screen size) had the highest bulk and tapped density of about 80 and 119 kg m-3; whereas, the wheat and oat grinds had the lowest of about 58 and 88–90 kg m-3. The results indicate that the bulk and tapped densities are inversely proportional to the particle size of the grinds. The flow properties of the grinds calculated are better for chopped straws compared to hammer milled using smaller screen size (19.05 mm).

  7. Combination of ultrasonic and Fenton processes in the presence of magnetite nanostructures prepared by high energy planetary ball mill.

    Science.gov (United States)

    Acisli, Ozkan; Khataee, Alireza; Karaca, Semra; Karimi, Atefeh; Dogan, Ercan

    2017-01-01

    High energy planetary ball milling process was used to prepare magnetite nanostructures from natural magnetite. The natural and ball-milled magnetite samples were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (HR-TEM), energy-dispersive X-ray spectroscopy (EDX), Brunauer-Emmett-Teller (BET) and Fourier transform infrared spectroscopy (FT-IR). The results of EDX indicated the presence of main elements including Fe and O in the structure of both unmodified and milled magnetite samples. The specific surface area of catalyst increased from 0.9116m 2 /g to 28.692m 2 /g after ball-milling process. The catalytic activity of prepared magnetite nanostructures was evaluated towards degradation of Acid Blue 185 (AB185) in ultrasonic assisted heterogeneous Fenton reaction. 6h ball-milled catalyst exhibited the higher catalytic activity in degradation of AB185. The high degradation efficiency was obtained at initial pH of 3. Increasing the concentration of H 2 O 2 from an optimum value of 15mM led to decrease in degradation efficiency because of scavenging effect of H 2 O 2 on hydroxyl radicals. The optimized catalyst concentration was obtained 1.5g/L. Increasing initial dye concentration from 20 to 120mg/L led to decrease in degradation efficiency from 99 to 88%. The prepared magnetite nanostructures exhibited good stability in repeated cycles. The produced intermediates of the degradation of AB185 in ultrasonic assisted heterogeneous Fenton process were monitored by GC-MS analysis. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Energy transport in cooling device by magnetic fluid

    International Nuclear Information System (INIS)

    Yamaguchi, Hiroshi; Iwamoto, Yuhiro

    2017-01-01

    Temperature sensitive magnetic fluid has a great potential with high performance heat transport ability as well as long distance energy (heat) transporting. In the present study experimental set-up was newly designed and constructed in order to measure basic heat transport characteristics under various magnetic field conditions. Angular dependence for the device (heat transfer section) was also taken into consideration for a sake of practical applications. The energy transfer characteristic (heat transport capability) in the magnetically-driven heat transport (cooling) device using the binary TSMF was fully investigated with the set-up. The obtained results indicate that boiling of the organic mixture (before the magnetic fluid itself reaching boiling point) effectively enhances the heat transfer as well as boosting the flow to circulate in the closed loop by itself. A long-distance heat transport of 5 m is experimentally confirmed, transferring the thermal energy of 35.8 W, even when the device (circulation loop) is horizontally placed. The highlighted results reveal that the proposed cooling device is innovative in a sense of transporting substantial amount of thermal energy (heat) as well as a long distance heat transport. The development of the magnetically-driven heat transport device has a great potential to be replaced for the conventional heat pipe in application of thermal engineering. - Highlights: • Temperature-sensitive magnetic fluid (TSMF) has a great heat transport ability. • Magnetically-driven heat transport device using binary TSMF is proposed. • The basic heat transport characteristics are investigated. • Boiling of the organic mixture effectively enhances the heat transfer. • A long-distance heat transport of 5 m is experimentally confirmed.

  9. Shale oil extraction with supercritical fluid and microwave energy

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Maoqi [Southwest Research Institute (United States)

    2011-07-01

    Shale oil extraction, an industrial process for unconventional oil production, is usually performed above ground (ex situ processing) by mining the oil shale and then treating it in processing facilities. Other modern technologies perform the processing underground (on-site or in situ processing) by applying heat and extracting the oil via oil wells. This paper gives an overview of the past field applications of electromagnetic heating on shale oil extraction, including technical challenges and limitations. Unconventional extraction technologies, such as ultrasound, microwave (radio frequency, electromagnetic wave), and fusion are presented. Then, the benefits of a hybrid technology based on a combination of supercritical fluids and microwave energy (SCF-EM) for shale oil extraction are discussed. A combination of several supercritical fluids is analyzed, such as water and CO2, the latter has been used in enhanced oil recovery for decades. In the end, a detailed techno-economic analysis presents the technical challenges, possible solutions and the market barriers.

  10. Effect of high energy milling time of the aluminum bronze alloy obtained by powder metallurgy with niobium carbide addition

    Energy Technology Data Exchange (ETDEWEB)

    Dias, Alexandre Nogueira Ottoboni; Silva, Aline da; Rodrigues, Carlos Alberto; Melo, Mirian de Lourdes Noronha Motta; Rodrigues, Geovani; Silva, Gilbert, E-mail: aottoboni@yahoo.com.br [Universidade Federal de Itajuba (UNIFEI), Itajuba, MG (Brazil)

    2017-05-15

    The aluminum bronze alloy is part of a class of highly reliable materials due to high mechanical strength and corrosion resistance being used in the aerospace and shipbuilding industry. It's machined to produce parts and after its use cycle, it's discarded, but third process is considered expensive and besides not being correct for environment reasons. Thus, reusing this material through the powder metallurgy (PM) route is considered advantageous. The aluminum bronze chips were submitted to high energy ball milling process with 3% of niobium carbide (NbC) addition. The NbC is a metal-ceramic composite with a ductile-brittle behaviour. It was analyzed the morphology of powders by scanning electron microscopy as well as particle size it was determined. X ray diffraction identified the phases and the influence of milling time in the diffractogram patterns. Results indicates that milling time and NbC addition improves the milling efficiency significantly and being possible to obtain nanoparticles. (author)

  11. Preparation and microwave absorbing properties in the X-band of natural ferrites from iron sands by high energy milling

    Science.gov (United States)

    Mashuri, X.; Lestari, W.; Triwikantoro, X.; Darminto, X.

    2018-01-01

    Bulk natural ferrites based in iron sands were synthesized at room temperature by high energy ball milling. The reduced particle sizes of the ferrites were milled at 100 rpm at selected time intervals of 0, 2, 4, and 6 h. The as-milled products were then characterized by x-ray diffraction (XRD), a vibrating sample magnetometer (VSM) and a vector network analyzer (VNA). The results showed that the magnetite phase contents, their mean size and the saturated magnetization of the natural ferrites were about 95 nm and 36–.50 emu g‑1 without a new phase. The microwave absorbing characteristics were investigated by measuring the absorption of electromagnetic waves in the frequency range 7–12 GHz. The maximum reflection loss (RL m) and matching frequency (f m) for the best process of milling (100 rpm, 6 h) of natural ferrites were RL m1  =  ‑7.28 dB in f m1  =  7.50 GHz (▵f  =  1.50 GHz) and RL m2  =  ‑4.31 dB in f m2  =10.28 GHz (▵f  =  2.57 GHz). These results suggest that synthesized natural ferrites can be employed as effective microwave absorbers in various devices.

  12. Solid-solid and gas-solid interactions induced during high-energy milling to produce PbTe nanopowders

    Energy Technology Data Exchange (ETDEWEB)

    Rojas-Chavez, H., E-mail: rojas_hugo@ittlahuac2.edu.mx [Instituto Tecnologico de Tlahuac - II (Mexico); Reyes-Carmona, F. [Facultad de Quimica - UNAM (Mexico); Garibay-Febles, V. [Instituto Mexicano del Petroleo, Laboratorio de Microscopia Electronica de Ultra Alta Resolucion (Mexico); Jaramillo-Vigueras, D. [Centro de Investigacion e Innovacion Tecnologica - IPN (Mexico)

    2013-05-15

    Transformations from precursors to nanoparticles by high-energy milling are promoted by two major driving forces, namely physical and/or chemical. While the former has been difficult to trace since stress, strain and recovery may occur almost simultaneously during milling, the latter has been sequentially followed as an evolution from precursors to intermediate phases and thereof to high purity nanocrystals. The specific objective of this work is to discern how solid-solid and partially solid-gas reactions manifest themselves correspondingly as a short-range diffusion through an interface or how vapor species, as a subliming phenomenon, grows as a different phase on an active local surface. These series of changes were traced by sub-cooling the as-milled powders extracted during a milling cycle. Through this experimental technique, samples were electron microscopically analyzed and where it was required, selected area electron diffraction images were obtained. High-resolution transmission electron microscopy results, unambiguously, confirm that nanocrystals in the last stage show a cubic morphology which average size distributions are around 17 nm.

  13. Surpassing the energy method for nonlinear fluid stability

    Science.gov (United States)

    Goluskin, David; Fuentes, Federico

    2017-11-01

    A basic question in fluid stability is whether a laminar flow is nonlinearly stable to all perturbations. The typical way to verify stability, called the energy method, is to show that the energy of a perturbation must decay monotonically. The energy method is known to be overly conservative in many systems, particularly when turbulence arises subcritically, such as in parallel shear flows. The energy method is a special case of a Lyapunov function method in which the Lyapunov function is the perturbation energy. This talk will present a more general approach in which the Lyapunov functions (1) are not restricted to being quadratic but instead are higher-degree polynomials, and (2) can depend explicitly on the spectrum of the velocity field in the eigenbasis of the energy stability operator. The optimal construction of such Lyapunov functions is complicated but can be done with computer assistance by formulating a polynomial optimization problem, which in turn is formulated as a semidefinite program. This talk will describe the general framework of the method. A companion talk by Federico Fuentes will illustrate its application to planar Couette flow, where we have verified nonlinear stability at larger Reynolds numbers than is possible using the energy method.

  14. Symmetric energy-momentum tensor in Maxwell, Yang-Mills, and Proca theories obtained using only Noether's theorem

    International Nuclear Information System (INIS)

    Montesinos, M.; Flores, E.

    2006-01-01

    The symmetric and gauge-invariant energy-momentum tensors for source-free Maxwell and Yang-Mills theories are obtained by means of translations in spacetime via a systematic implementation of Noether's theorem. For the source-free neutral Proca field, the same procedure yields also the symmetric energy-momentum tensor. In all cases, the key point to get the right expressions for the energy-momentum tensors is the appropriate handling of their equations of motion and the Bianchi identities. It must be stressed that these results are obtained without using Belinfante's symmetrization techniques which are usually employed to this end. (Author)

  15. Effects of high energy ball milling on synthesis and characteristics of Ti-Mg alloys

    CSIR Research Space (South Africa)

    Chikwanda, HK

    2008-01-01

    Full Text Available The synthesis of Ti-Mg alloys using mechanical alloying method has been investigated. Effects of the mechanical alloying parameters on the resultant microstructural features have been studied. This work presents the effects of milling speed...

  16. POTENTIALITIES OF ELECTRIC ENERGY DELIVERY IN TWO SUGAR MILLS OF CIENFUEGOS PROVINCE

    Directory of Open Access Journals (Sweden)

    Reinier Jiménez Borges

    2017-04-01

    Full Text Available In this work the thermal-energetic schemes of the "14 de Julio" and "Antonio Sanchez" sugar mills belonging to the province of Cienfuegos are analyzed. In these enterprises Process Flow and Information Flow diagrams for its later simulation in the Termoazucar software (STA 4.1 were developed. With the help of reference software, base case modeling in these plants allowed to identify opportunities for improvement of thermal schemes. The implementation of them in the modeling of improved cases of these mills facilitated to be aware of the possibility of increases of 16% in the electricity sold to Eletroenergetic National System (SEN in the "14 de Julio" sugar mill and 50% in the "Antonio Sanchez" sugar mill keeping both the same levels of ground.

  17. Current techniques in rice mill effluent treatment: Emerging opportunities for waste reuse and waste-to-energy conversion.

    Science.gov (United States)

    Kumar, Anuj; Priyadarshinee, Rashmi; Roy, Abhishek; Dasgupta, Dalia; Mandal, Tamal

    2016-12-01

    Rice mills release huge volumes of wastewater and other by-products when processing paddy rice. The wastewater often contains toxic inorganic and organic contaminants which cause environmental damage when released. Accordingly, cost-effective techniques for removing contaminants are needed. This article reviews current processes for curbing pollution and also reusing and recycling waste products. Novel techniques exist for converting waste products into energy and value-added products. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Correlations of the energy-momentum tensor via gradient flow in SU(3) Yang-Mills theory at finite temperature

    Science.gov (United States)

    Kitazawa, Masakiyo; Iritani, Takumi; Asakawa, Masayuki; Hatsuda, Tetsuo

    2017-12-01

    Euclidean two-point correlators of the energy-momentum tensor (EMT) in SU(3) gauge theory on the lattice are studied on the basis of the Yang-Mills gradient flow. The entropy density and the specific heat obtained from the two-point correlators are shown to be in good agreement with those from the one-point functions of EMT. These results constitute a first step toward the first principle simulations of the transport coefficients with the gradient flow.

  19. Non-perturbative renormalization of the energy-momentum tensor in SU(3) Yang-Mills theory

    OpenAIRE

    Giusti, Leonardo; Pepe, Michele

    2014-01-01

    We present a strategy for a non-perturbative determination of the finite renormalization constants of the energy-momentum tensor in the SU(3) Yang-Mills theory. The computation is performed by imposing on the lattice suitable Ward Identites at finite temperature in presence of shifted boundary conditions. We show accurate preliminary numerical data for values of the bare coupling g_0^2 ranging for 0 to 1.

  20. Phenolic compounds removal from mimosa tannin model water and olive mill wastewater by energy-efficient electrocoagulation process

    OpenAIRE

    Marijana Kraljić Roković; Mario Čubrić; Ozren Wittine

    2014-01-01

    The objective of this work was to study the influence of NaCl concentration, time, and current density on the removal efficiency of phenolic compounds by electrocoagulation process, as well as to compare the specific energy consumption (SEC) of these processes under different experimental conditions. Electrocoagulation was carried out on two different samples of water: model water of mimosa tannin and olive mill wastewater (OMW). Low carbon steel electrodes were used in the experiments. The p...

  1. Saving electrical energy in a saw-mill; Einsparung von elektrischer Energie in einem Saegereibetrieb. Stromeinsparungen in den Bereichen Holzbearbeitung, Foerdertechnik, Holztrocknung, Absauganlagen, Druckluft, Beleuchtung

    Energy Technology Data Exchange (ETDEWEB)

    Wyrsch, I. [Wyrsch Technologies, Kuessnacht am Rigi (Switzerland); Dolder, M. [Ingenieurbuero Dolder, Luzern (Switzerland)

    2005-01-15

    This comprehensive, illustrated report for the Swiss Federal Office of Energy (SFOE) presents the findings of a project that examined the electricity consumption of saw-mills and ways in which the amount of electrical power used in such facilities could be reduced. The Schilliger Holz AG company was taken as an example of a saw-mill in Switzerland. Its power consumption in 2001 was almost 6 gigawatt-hours. The work done in the two phases of the project is described and commented on. The first phase involved the measurement and analysis of power consumption; in the second phase measures to be taken to help save energy were developed. The various machinery and installations in this saw mill are described. These include various systems for the processing of the raw timber through to finished products that include wood for building, decoration and laminates. Measurement data is presented and commented on. Potentials for saving electricity and measures to be taken are described in detail for the various processing plants in the saw-mill.

  2. Spark plasma sintered Sm(2)Co(17)-FeCo nanocomposite permanent magnets synthesized by high energy ball milling.

    Science.gov (United States)

    Sreenivasulu, G; Gopalan, R; Chandrasekaran, V; Markandeyulu, G; Suresh, K G; Murty, B S

    2008-08-20

    Nanocomposite Sm(2)Co(17)-5 wt% FeCo magnets were synthesized by high energy ball milling followed by consolidation into bulk shape by the spark plasma sintering technique. The evolution of magnetic properties was systematically investigated in milled powders as well as in spark plasma sintered samples. A high energy product of 10.2 MGOe and the other magnetic properties of M(s) = 107 emu g(-1), M(r) = 59 emu g(-1), M(r)/M(s) = 0.55 and H(c) = 6.4 kOe were achieved in a 5 h milled and spark plasma sintered Sm(2)Co(17)-5 wt% FeCo nanocomposite magnet. The spark plasma sintering was carried out at 700 °C for 5 min with a pressure of 70 MPa. The nanocomposite showed a higher Curie temperature of 955 °C for the Sm(2)Co(17) phase in comparison to its bulk Curie temperature for the Sm(2)Co(17) phase (920 °C). This higher Curie temperature can improve the performance of the magnet at higher temperatures.

  3. Magnetic and frequency properties for nanocrystalline Fe-Ni alloys prepared by high-energy milling method

    International Nuclear Information System (INIS)

    Liu Yongsheng; Zhang Jincang; Yu, Liming; Jia Guangqiang; Jing Chao; Cao Shixun

    2005-01-01

    Fe-based nano-crystalline soft magnetic alloy with Ni-doping was fabricated successfully by high-energy milling. It was proved that a Fe-Ni solid solution is formed and the evaluated average grain size is about 20 nm. The effect of doping Ni on the frequency properties was systematically investigated. From the magnetic measurement results, it can be concluded that, the nickel doped decreases the resonance frequency of Fe-Ni alloy, but Ni doping enhances the frequency stability. The corresponding value of initial permeability as a function of Ni doping concentration was given at 10 kHz and the result indicates that the peak value of initial permeability shifts to the region of low Ni concentration for the samples milled for 72 h

  4. Rare-Earth Three-Dimensional Transition Metal Nanoparticles and Nanoflakes by Surfactant-Assisted High-Energy Ball Milling

    Science.gov (United States)

    Gunduz Akdogan, Nilay

    The research work in this dissertation, was focused on the fabrication of magnetic nanoparticles and nanoflakes by high-energy ball milling (HEBM), the understanding of their formation and the study of their fundamental and hard magnetic properties as a function of size and shape. A successful fabrication of (Sm, Nd & Pr)-Co, and Nd2Fe14B anisotropic nanoparticles is needed for the development of anisotropic nanocomposite permanent magnets using the bottom-up approach. A novel approach has been employed for the fabrication, which is surfactant-assisted high-energy ball milling. A two-step HEBM was used to prepare the nanoparticles and the nanoflakes. In the first step the coarse powders were brought into the nanocrystalline state by using HEBM in heptane without the presence of surfactants. Surfactants during the milling process leads to the dispersion of crashed particles in the appropriate organic solvent, preventing them from welding, and enabling them to a better size refinement. A strong correlation between the grain size of the nanoflakes and the size of the nanoparticles has been observed. The data suggests that the nanoparticles break from the nanoflakes along the grain boundaries during milling. The intrinsic properties of the nanoparticles, including the saturation magnetization MS, the magnetocrystalline anisotropy K and the spin reorientation temperature TSP have been found to decrease drastically with decreasing particle size. This behavior has been attributed mostly to surface disorder and thermal effects. Magnetically hard Nd2Fe14B nanopowders with RT coercivity in the range of 1.2 - 4 kOe have been produced. The coercivity shows a strong dependence on particle size. As the particle size decreases, the coercivity is found to decrease substantially. This effect is related the reduced magnetocrystalline anisotropy of the nanoparticle and to thermal effects.

  5. Effect of process variables on synthesis of MgB2 by a high energy ball mill

    Directory of Open Access Journals (Sweden)

    Kurama Haldun

    2016-01-01

    Full Text Available The discovery of superconductivity of MgB2 in 2001, with a critical temperature of 39 K, offered the promise of important large-scale applications at around 20 K. Except than the other featured synthesis methods, mechanical activation performed by high energy ball mills, as bulk form synthesis or as a first step of wire and thin film productions, has considered as an effective alternative production route in recent years. The process of mechanical activation (MA starts with mixing the powders in the right proportion and loading the powder mixture into the mill with the grinding media. The milled powder is then consolidated into a bulk shape and heat-treated to obtain desired microstructure and properties. Thus, the important components of the MA process are the raw materials, mill type and process variables. During the MA process, heavy deformation of particles occure. This is manifested by the presence of a variety of crystal defects such as dislocations, vacancies, stacking faults and increased number of particle boundaries. The presence of this defect structure enhances the diffusivity of solute hence the critical currents and magnetic flux pinning ability of MgB2 are improved. The aim of the present study is to determine the effects of process variables such as ball-to-powder mass ratio, size of balls, milling time, annealing temperature and contribution of process control agent (toluene on the product size, morphology and conversion level of precursor powders to MgB2 after subsequent heat treatment. The morphological analyses of the samples were performed by a high vacuum electron microscope ZEISS SUPRA VP 50. The phase compositions of the samples were performed with an Rigaku-Rint 2200 diffractometer, with nickel filtered Cu Kα radiation and conversion level. The MgB2 phase wt % was calculated by the Rietveld refinement method. The obtained results were discussed according to the process variables to find out their affect on the structure

  6. Excess heat from kraft pulp mills. Trade-offs between internal and external use in the case of Sweden. Part 2. Results for future energy market scenarios

    International Nuclear Information System (INIS)

    Joensson, Johanna; Berntsson, Thore; Svensson, Inger-Lise; Moshfegh, Bahram

    2008-01-01

    In this paper the trade-off between internal and external use of excess heat from a kraft pulp mill is investigated for four different future energy market scenarios. The work follows the methodology described in Svensson et al. [2008. Excess heat from kraft pulp mills: trade-offs between internal and external use in the case of Sweden - Part 1: methodology. Energy Policy, submitted for publication], where a systematic approach is proposed for investigating the potential for profitable excess heat cooperation. The trade-off is analyzed by economic optimization of an energy system model consisting of a pulp mill and an energy company (ECO). In the model, investments can be made, which increase the system's energy efficiency by utilization of the mill's excess heat, as well as investments that increase the electricity production. The results show that the trade-off depends on energy market prices, the district heating demand and the type of existing heat production. From an economic point of view, external use of the excess heat is preferred for all investigated energy market scenarios if the mill is studied together with an ECO with a small heat load. For the cases with medium or large district heating loads, the optimal use of excess heat varies with the energy market price scenarios. However, from a CO 2 emissions perspective, external use is preferred, giving the largest reduction of global emissions in most cases. (author)

  7. The synthesis, microstructure, hardness and thermal properties of bulk nanocrystalline Al produced by in situ consolidation with low-energy ball milling

    International Nuclear Information System (INIS)

    Zhao, K.Y.; LI, C.J.; Tao, J.M.; Ng, Dickon H.L.; Zhu, X.K.

    2010-01-01

    Bulk nanocrystalline (nc) Al was produced by in situ consolidation of Al powder with low-energy ball milling at room temperature. Microstructure and thermal properties of Al subjected to ball milling were investigated by means of differential scanning calorimeter (DSC), differential thermal analyzer (DTA), transmission electron microscope (TEM), X-ray diffraction (XRD), and scanning electron microscope (SEM). As a result of long time milling, considerable energy has been stored in the powder particles which suffered a repetitive cold welding and fracture mechanism. It was found that the microhardness of Al was increased with the increasing of ball milling time. The highest microhardness (1372 MPa) was observed at room temperature in nanocrystalline Al in the experiment.

  8. Structure and thermal stability of nanostructured iron-doped zirconia prepared by high-energy ball milling

    DEFF Research Database (Denmark)

    Jiang, Jianzhong; Poulsen, Finn Willy; Mørup, Steen

    1999-01-01

    Fury stability cubic zirconia doped with iron oxide has been synthesized by high-energy ball milling from powder mixtures of monoclinic zirconia and hematite. It is found that the iron ions dissolved in cubic ZrO2 are in substitutional positions with a maximum solubility of approximately 18.5 mol......% alpha-Fe2O3. The unit-cell volume of the cubic ZrO2 phase decreases with increasing iron content. During heating hte cubic-to-tetragonal transition occurs at approximately 827 degrees C and the tetragonal-to-monoclinic transition seems to be absent at temperatures below 950 degrees C. During cooling...

  9. Energy effects on the structure and thermodynamic properties of nanoconfined fluids (a density functional theory study).

    Science.gov (United States)

    Keshavarzi, Ezat; Kamalvand, Mohammad

    2009-04-23

    The structure and properties of fluids confined in nanopores may show a dramatic departure from macroscopic bulk fluids. The main reason for this difference lies in the influence of system walls. In addition to the entropic wall effect, system walls can significantly change the energy of the confined fluid compared to macroscopic bulk fluids. The energy effect of the walls on a nanoconfined fluid appears in two forms. The first effect is the cutting off of the intermolecular interactions by the walls, which appears for example in the integrals for calculation of the thermodynamic properties. The second wall effect involves the wall-molecule interactions. In such confined fluids, the introduction of wall forces and the competition between fluid-wall and fluid-fluid forces could lead to interesting thermodynamic properties, including new kinds of phase transitions not observed in the macroscopic fluid systems. In this article, we use the perturbative fundamental measure density functional theory to study energy effects on the structure and properties of a hard core two-Yukawa fluid confined in a nanoslit. Our results show the changes undergone by the structure and phase transition of the nanoconfined fluids as a result of energy effects.

  10. Energy use and implications for efficiency strategies in global fluid-milk processing industry

    International Nuclear Information System (INIS)

    Xu Tengfang; Flapper, Joris

    2009-01-01

    The fluid-milk processing industry around the world processes approximately 60% of total raw milk production to create diverse fresh fluid-milk products. This paper reviews energy usage in existing global fluid-milk markets to identify baseline information that allows comparisons of energy performance of individual plants and systems. In this paper, we analyzed energy data compiled through extensive literature reviews on fluid-milk processing across a number of countries and regions. The study has found that the average final energy intensity of individual plants exhibited significant large variations, ranging from 0.2 to 12.6 MJ per kg fluid-milk product across various plants in different countries and regions. In addition, it is observed that while the majority of larger plants tended to exhibit higher energy efficiency, some exceptions existed for smaller plants with higher efficiency. These significant differences have indicated large potential energy-savings opportunities in the sector across many countries. Furthermore, this paper illustrates a positive correlation between implementing energy-monitoring programs and curbing the increasing trend in energy demand per equivalent fluid-milk product over time in the fluid-milk sector, and suggests that developing an energy-benchmarking framework, along with promulgating new policy options should be pursued for improving energy efficiency in global fluid-milk processing industry.

  11. Relaxation of superfluid vortex bundles via energy transfer to the normal fluid

    International Nuclear Information System (INIS)

    Kivotides, Demosthenes

    2007-01-01

    We apply numerical and computational analyses to the decay of a topologically nontrivial, bundle-structured superfluid vortex tangle via mutual friction effected energy transfer to an initially stationary, viscous normal fluid. We demonstrate that, as long as the coherent superfluid vorticity structures remain intact, the induced normal-fluid vorticity acquires a similar to the superfluid vorticity morphology, and the normal-fluid energy spectrum mimics the superfluid energy spectrum presenting a low-wavenumber scaling regime. After a (smaller than the integral advective time scale) transient, the superfluid vorticity bundles disintegrate; this is followed by the decay of normal-fluid energy. The kinetic energies of the two fluids are mismatched throughout the decay period, and the dismantling of coherent vorticity destroys the low-wavenumber energy spectrum scaling in both fluids. At the point of maximum normal-fluid energy, the circulation of the induced normal-fluid vortices is comparable to the ''macroscopic'' circulation of the superfluid vorticity bundles. We show that the superfluid dynamics are dominated throughout the decay period by inertial rather than mutual friction effects, that the formation of bundlelike coherent superfluid vortices cannot be the outcome of pure (reconnecting) Biot-Savart dynamics, and that superfluid vortex length dynamics are not analogous to superfluid energy dynamics. We conjecture that the dynamics of fully developed, turbulent thermal superfluid flow could be described in terms of interactions of cyclic coherent vorticity patterns in both fluids

  12. Properties of Y-TZP/Al{sub 2}O{sub 3} ceramic nanocomposites obtained by high-energy ball milling

    Energy Technology Data Exchange (ETDEWEB)

    Santos, C. [Universidade de Sao Paulo - Escola de Engenharia de Lorena (USP-EEL), Polo Urbo-Industrial, Gleba AI-6, s/n, Lorena-SP, CEP 12600-000 (Brazil); Universidade do Estado do Rio de Janeiro, Faculdade de Tecnologia (UERJ-FAT), Rodovia Presidente Dutra, km 298, Resende-RJ, CEP 27511-971 (Brazil)], E-mail: claudinei@demar.eel.usp.br; Koizumi, M.H.; Daguano, J.K.M.F.; Santos, F.A. [Universidade de Sao Paulo - Escola de Engenharia de Lorena (USP-EEL), Polo Urbo-Industrial, Gleba AI-6, s/n, Lorena-SP, CEP 12600-000 (Brazil); Elias, C.N. [Instituto Militar de Engenharia - Departamento de Ciencia e Engenharia de Materiais (IME - DCEM), Pca. General Tiburcio, 80, Praia Vermelha, Rio de Janeiro-RJ, CEP 22290-270 (Brazil); Universidade do Estado do Rio de Janeiro, Faculdade de Tecnologia (UERJ-FAT), Rodovia Presidente Dutra, km 298, Resende-RJ, CEP 27511-971 (Brazil); Ramos, A.S. [Universidade do Vale do Paraiba - Instituto de Pesquisa e Desenvolvimento (UNIVAP-IP and D), Av. Shishima Hifumi, 2911, Urbanova, S.J.Campos-SP, CEP 12244-000 (Brazil)

    2009-02-25

    In this work, the synthesis of Y{sub 2}O{sub 3} stabilized tetragonal zirconia polycrystals (Y-TZP)-alumina (Al{sub 2}O{sub 3}) powder mixture was performed by high-energy ball milling and the sintering behavior of this composite was investigated. In order to understand the phase transformations occurring during ball milling, samples were collected after different milling times, from 1 to 60 h. The milled powders were compacted by cold uniaxial pressing and sintered at 1400 and 1600 deg. C. Both powders and sintered samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometry analysis (EDS) and mechanical properties. Fully dense samples were obtained after sintering at 1600 deg. C, while the samples sintered at 1400 deg. C presented a full density for powder mixtures milled for 30 and 60 h. Fracture toughness and Vickers hardness values of the Y-TZP/Al{sub 2}O{sub 3} nanocomposite were improved due to dispersed Al{sub 2}O{sub 3} grains and reduced ZrO{sub 2} grain size. Samples sintered at 1400 deg. C, based on powders milled for 60 h, presented high K{sub IC} and hardness values near to 8.0 MPam{sup 1/2} and 15 GPa, respectively.

  13. Interfacial Reaction During High Energy Ball Milling Dispersion of Carbon Nanotubes into Ti6Al4V

    Science.gov (United States)

    Adegbenjo, A. O.; Olubambi, P. A.; Potgieter, J. H.; Nsiah-Baafi, E.; Shongwe, M. B.

    2017-12-01

    The unique thermal and mechanical properties of carbon nanotubes (CNTs) have made them choice reinforcements for metal matrix composites (MMCs). However, there still remains a critical challenge in achieving homogeneous dispersion of CNTs in metallic matrices. Although high energy ball milling (HEBM) has been reported as an effective method of dispersing CNTs into metal matrices, a careful selection of the milling parameters is important not to compromise the structural integrity of CNTs which may cause interfacial reactions with the matrix. In this study, multi-walled carbon nanotubes (MWCNTs) were purified by annealing in argon and vacuum atmospheres at 1000 and 1800 °C, respectively, for 5 h to remove possible metallic catalyst impurities. Subsequently, 1, 2 and 3 wt.% MWCNTs were dispersed by adapted HEBM into Ti6Al4V alloy metal matrix. Raman spectroscopy (RS), x-ray diffraction, scanning electron microscopy, energy-dispersive x-ray spectrometry and transmission electron microscopy techniques were used to characterize the as-received and annealed MWCNTs, as well as the admixed MWCNT/Ti6Al4V nanocomposite powders. The experimental results showed that vacuum annealing successfully eliminated retained nickel (Ni) catalysts from MWCNTs, while the adapted HEBM method achieved a relative homogeneous dispersion of MWCNTs into the Ti6Al4V matrix and helped to control interfacial reactions between defective MWCNTs and the metal matrix.

  14. Comparison of Viscous and Pressure Energy Exchange in Fluid Flow Induction

    Science.gov (United States)

    1981-06-01

    that it compares energy added to the secondary fluid to total energy added to the system by the primary fluid. Eva - luation of the fluids total head...found in Reference [10]. 61 - it C. INTERACTION CHAMBER LOSSES Losses in the interaction chamber are difficult to eva - luate. Different approaches should...Lockwood, R. M., Sargent, E. R., and Beckett, J. F., "Thrust Augmented Intermittent Jet Lift-Propulsion System Pulse Reactor", Hiller Aircraft Corp

  15. Gathering straw energy balance for co-generation in sugarcane mills; Balanco energetico do recolhimento da palha para cogeracao de energia em usinas de cana-de-acucar

    Energy Technology Data Exchange (ETDEWEB)

    Veiga, Joao Paulo Soto; Bizzo, Waldir Antonio; Carvalho, Danilo Jose; Berton, Rafael Piatto [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Fac. de Engenharia Mecanica; Linero, Francisco Antonio Barba [Centro de Tecnologia Canavieira (CTC), Piracicaba, SP (Brazil)], E-mails: jpsveiga@fem.unicamp.br, bizzo@fem.unicamp.br, linero@ctc.com.br, liar@fem.unicamp.br, rpberton@fem.unicamp.br

    2012-11-01

    With the requirement and expansion of sugarcane harvest without burning the straw in the field of began to be seen as a potential fuel for co-generation sugarcane mills together bagasse. This study examined the productivity and three ways of gathering and transportation of straw in order to determine the potential energy available in biomass residues and their respective energy consumption on gathering and transport operations. To this were determined parameters for the production of waste per hectare, minimum quantity to be left in the field for maintenance of soil organic carbon and erosion reducing, the amount of straw recovered and milled at the mill, material humidity and diesel and electricity consumption of each step to obtain the final balance of energy recovered. (author)

  16. Dispersion of silicon carbide nanoparticles in a AA2024 aluminum alloy by a high-energy ball mill

    Energy Technology Data Exchange (ETDEWEB)

    Carreño-Gallardo, C.; Estrada-Guel, I. [Centro de Investigación en Materiales Avanzados (CIMAV), Laboratorio Nacional de Nanotecnología-Chihuahua, Miguel de Cervantes No. 120, CP 31109, Chihuahua, México (Mexico); López-Meléndez, C. [Universidad La Salle Chihuahua, Prol. Lomas de Majalca No. 11201, CP 31020, Chihuahua, México (Mexico); Martínez-Sánchez, R., E-mail: roberto.martinez@cimav.edu.mx [Centro de Investigación en Materiales Avanzados (CIMAV), Laboratorio Nacional de Nanotecnología-Chihuahua, Miguel de Cervantes No. 120, CP 31109, Chihuahua, México (Mexico)

    2014-02-15

    Highlights: • Synthesis of 2024-SiC{sub NP} nanocomposite by mechanical milling process. • SiC nanoparticles improved mechanical properties of aluminum alloy 2024 matrix. • A homogeneous distribution of SiC nanoparticles were observed in the matrix • Compressive and hardness properties of the composite are improved significantly. -- Abstract: Al{sub 2024} alloy was reinforced with silicon carbide nanoparticles (SiC{sub NP}), whose concentration was varied in the range from 0 to 5 wt.%; some composites were synthesized with the mechanical milling (MM) process. Structure and microstructure of the consolidated samples were studied by X-ray diffraction and transmission electron microscopy, while mechanical properties were investigated by compressive tests and hardness measurements. The microstructural evidence shows that SiC{sub NP} were homogeneously dispersed into the Al{sub 2024} alloy using high-energy MM after 2 h of processing. On the other hand, an increase of the mechanical properties (yield stress, maximum strength and hardness) was observed in the synthesized composites as a direct function of the SiC{sub NP} content. In this research several strengthening mechanisms were observed, but the main was the obstruction of dislocations movement by the addition of SiC{sub NP}.

  17. Synthesis and characterization of magnetite-maghemite nanoparticles obtained by the high-energy ball milling method

    Science.gov (United States)

    Velásquez, A. A.; Marín, C. C.; Urquijo, J. P.

    2018-03-01

    We present the process of synthesis and characterization of magnetite-maghemite nanoparticles by the ball milling method. The particles were synthesized in a planetary ball mill equipped with vials and balls of tempered steel, employing dry and wet conditions. For dry milling, we employed microstructured analytical-grade hematite (α-Fe2O3), while for wet milling, we mixed hematite and deionized water. Milling products were characterized by X-ray diffraction, transmission electron microscopy, room temperature Mössbauer spectroscopy, vibrating sample magnetometry, and atomic absorption spectroscopy. The Mössbauer spectrum of the dry milling product was well fitted with two sextets of hematite, while the spectrum of the wet milling product was well fitted with three sextets of spinel phase. X-ray measurements confirmed the phases identified by Mössbauer spectroscopy in both milling conditions and a reduction in the crystallinity of the dry milling product. TEM measurements showed that the products of dry milling for 100 h and wet milling for 24 h consist of aggregates of nanoparticles distributed in size, with mean particle size of 10 and 15 nm, respectively. Magnetization measurements of the wet milling product showed little coercivity and a saturation magnetization around 69 emu g-1, characteristic of a nano-spinel system. Atomic absorption measurements showed that the chromium contamination in the wet milling product is approximately two orders of magnitude greater than that found in the dry milling product for 24 h, indicating that the material of the milling bodies, liberated more widely in wet conditions, plays an important role in the conversion hematite-spinel phase.

  18. Estimating the Impact (Energy, Emissions and Economics) of the US Fluid Power Industry

    Energy Technology Data Exchange (ETDEWEB)

    Love, Lonnie J [ORNL

    2012-12-01

    The objective of this report is to estimate the impact (energy, emissions and economics) of United Fluid power (hydraulic and pneumatic actuation) is the generation, control, and application of pumped or compressed fluids when this power is used to provide force and motion to mechanisms. This form of mechanical power is an integral part of United States (U.S.) manufacturing and transportation. In 2008, according to the U.S. Census Bureau, sales of fluid power components exceeded $17.7B, sales of systems using fluid power exceeded $226B. As large as the industry is, it has had little fundamental research that could lead to improved efficiency since the late 1960s (prior to the 1970 energy crisis). While there have been some attempts to replace fluid powered components with electric systems, its performance and rugged operating condition limit the impact of simple part replacement. Oak Ridge National Laboratory and the National Fluid Power Association (NFPA) collaborated with 31 industrial partners to collect and consolidate energy specific measurements (consumption, emissions, efficiency) of deployed fluid power systems. The objective of this study was to establish a rudimentary order of magnitude estimate of the energy consumed by fluid powered systems. The analysis conducted in this study shows that fluid powered systems consumed between 2.0 and 2.9 Quadrillion (1015) Btus (Quads) of energy per year; producing between 310 and 380 million metric tons (MMT) of Carbon Dioxide (CO2). In terms of efficiency, the study indicates that, across all industries, fluid power system efficiencies range from less than 9% to as high as 60% (depending upon the application), with an average efficiency of 22%. A review of case studies shows that there are many opportunities to impact energy savings in both the manufacturing and transportation sectors by the development and deployment of energy efficient fluid power components and systems.

  19. Volatile components and key odorants of fennel (Foeniculum vulgare Mill.) and thyme (Thymus vulgaris L.) oil extracts obtained by simultaneous distillation-extraction and supercritical fluid extraction.

    Science.gov (United States)

    Díaz-Maroto, M Consuelo; Díaz-Maroto Hidalgo, Ignacio Javier; Sánchez-Palomo, Eva; Pérez-Coello, M Soledad

    2005-06-29

    Volatile oil extracts of fennel seeds (Foeniculum vulgare Mill.) and thyme leaves (Thymus vulgaris L.) were obtained by simultaneous distillation-extraction (SDE) and supercritical fluid extraction (SFE) and analyzed by gas chromatography-mass spectrometry (GC-MS). In general, fennel oil extracted by SDE and SFE showed similar compositions, with trans-anethole, estragole, and fenchone as the main components. In contrast, thymol and p-cymene, the most abundant compounds in thyme leaves, showed big differences, with generally higher amounts of monoterpenes obtained by SDE. However, in this case, the differences between the extracts were higher. Key odorants of fennel seeds determined by gas chromatography-olfactometry (GC-O) showed similar patterns when applying SDE and SFE. trans-Anethole (anise, licorice), estragole (anise, licorice, sweet), fenchone (mint, camphor, warm), and 1-octen-3-ol (mushroom) were the most intense odor compounds detected in fennel extracts. Thymol and carvacrol, with oregano, thyme, and spicy notes, were identified as key compounds contributing to the aroma of thyme leaves.

  20. Composition of sugar cane, energy cane, and sweet sorghum suitable for ethanol production at Louisiana sugar mills.

    Science.gov (United States)

    Kim, Misook; Day, Donal F

    2011-07-01

    A challenge facing the biofuel industry is to develop an economically viable and sustainable biorefinery. The existing potential biorefineries in Louisiana, raw sugar mills, operate only 3 months of the year. For year-round operation, they must adopt other feedstocks, besides sugar cane, as supplemental feedstocks. Energy cane and sweet sorghum have different harvest times, but can be processed for bio-ethanol using the same equipment. Juice of energy cane contains 9.8% fermentable sugars and that of sweet sorghum, 11.8%. Chemical composition of sugar cane bagasse was determined to be 42% cellulose, 25% hemicellulose, and 20% lignin, and that of energy cane was 43% cellulose, 24% hemicellulose, and 22% lignin. Sweet sorghum was 45% cellulose, 27% hemicellulose, and 21% lignin. Theoretical ethanol yields would be 3,609 kg per ha from sugar cane, 12,938 kg per ha from energy cane, and 5,804 kg per ha from sweet sorghum.

  1. Eco-design of low energy mechanical milling through implementation of quality function deployment and design for sustainability

    Science.gov (United States)

    Rashid, Muhammad Hanif Abd; Nor, Nik Hisyamudin Muhd; Selamat, Siti Norhana; Hassan, Mohd Fahrul; Rahim, Abd Khalil Abd; Ahmad, Mohd Fauzi; Ismail, Al Emran; Omar, Badrul; Mokhtar, Mohd Faiz; Turan, Faiz Mohd; Yokoyama, Seiji

    2017-04-01

    Malaysia as a developing country favor energy demand by years which created mainly from fossil fuel. Unfortunately, the action leads to significant increment in carbon dioxide (CO2) emission that causing the global warming. The most promising mitigation strategy is by deploying Carbon Capture and Storage (CCS) technology where mineral carbonation was identified as the safest method for permanent storage and does not require continuous monitoring. Accordingly, National Green Technology was launched in 2009 to support the growth of green technology development in Malaysia as a carbon mitigation strategy. Thus, this paper aims to propose the development of a conceptual eco-design for Low Energy Mechanical Milling (LEMM). The concept was proposed by using the Quality Function Deployment (QFD) tool with combination of sustainability determinants (DFS) namely economic, environmental and social which evaluated using Solidworks 2015 sustainability assessment. The results show the new product targets for LEMM in prior on energy consumption (MJ), selling price (MYR), material cost (MYR), carbon footprint (kg CO2) with weightage of 5.2, 4.2, 3.6 and 3.6 respectively. The implementation of DFS criteria into the QFD promote to reduce material used by 16%, 35% reduction of carbon footprint, 28% less energy consumption, 28% lower air acidification, 77% of water eutrophication declined and increased recyclability by 15%.

  2. An accurate model for numerical prediction of piezoelectric energy harvesting from fluid structure interaction problems

    International Nuclear Information System (INIS)

    Amini, Y; Emdad, H; Farid, M

    2014-01-01

    Piezoelectric energy harvesting (PEH) from ambient energy sources, particularly vibrations, has attracted considerable interest throughout the last decade. Since fluid flow has a high energy density, it is one of the best candidates for PEH. Indeed, a piezoelectric energy harvesting process from the fluid flow takes the form of natural three-way coupling of the turbulent fluid flow, the electromechanical effect of the piezoelectric material and the electrical circuit. There are some experimental and numerical studies about piezoelectric energy harvesting from fluid flow in literatures. Nevertheless, accurate modeling for predicting characteristics of this three-way coupling has not yet been developed. In the present study, accurate modeling for this triple coupling is developed and validated by experimental results. A new code based on this modeling in an openFOAM platform is developed. (paper)

  3. Boson-fermion and boson-boson scattering in a Yang-Mills theory at high energy: Sixth-order perturbation theory

    International Nuclear Information System (INIS)

    McCoy, B.M.; Wu, T.T.

    1976-01-01

    Our previous study of Yang-Mills fields is extended by calculating the high-energy behavior of the boson-fermion and of the boson-boson amplitude in sixth-order perturbation theory. In the isovector and isoscalar channels of both these processes the behavior of the amplitude is the same as that found in fermion-fermion scattering

  4. Vibration energy harvesting in a small channel fluid flow using piezoelectric transducer

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, Md. Mehedi, E-mail: buetmehedi10@gmail.com; Hossain, Md. Yeam, E-mail: yeamhossain@gmail.com; Mazumder, Rakib, E-mail: rakibmazumder46075@gmail.com; Rahman, Roussel, E-mail: roussel.rahman@gmail.com; Rahman, Md. Ashiqur, E-mail: ashiqurrahman@me.buet.ac.bd [Department of Mechanical Engineering, Bangladesh University of Engineering and Technology (BUET), Dhaka-1000 (Bangladesh)

    2016-07-12

    This work is aimed at developing a way to harvest energy from a fluid stream with the application of piezoelectric transducers in a small channel. In this COMSOL Multiphysics based simulation study, it is attempted to harvest energy from the abundant renewable source of energy available in the form of kinetic energy of naturally occurring flow of fluids. The strategy involves harnessing energy from a fluid-actuator through generation of couples, eddies and vortices, resulting from the stagnation and separation of flow around a semi-circular bluff-body attached to a cantilever beam containing a piezoceramic layer. Fluctuation of fluidic pressure impulse on the beam due to vortex shedding and varying lift forces causes the flexible cantilever beam to oscillate in the direction normal to the fluid flow in a periodic manner. The periodic application and release of a mechanical strain upon the beam effected a generation of electric potential within the piezoelectric layer, thus enabling extraction of electrical energy from the kinetic energy of the fluid. The piezoelectric material properties and transducer design are kept unchanged throughout the study, whereas the configuration is tested with different fluids and varying flow characteristics. The size and geometry of the obstructing entity are systematically varied to closely inspect the output from different iterations and for finding the optimum design parameters. The intermittent changes in the generated forces and subsequent variation in the strain on the beam are also monitored to find definitive relationship with the electrical energy output.

  5. Direct mechanical energy measures of hammer mill comminution of switchgrass, wheat straw, and corn stover and analysis of their particle size distributions

    Energy Technology Data Exchange (ETDEWEB)

    Bitra, V.S.P [University of Tennessee; Womac, A.R. [University of Tennessee; Chevanan, Nehru [University of Tennessee; Miu, P.I. [University of Tennessee; Smith, D.R. [University of Tennessee; Igathinathane, C. [Mississippi State University (MSU); Sokhansanj, Shahabaddine [ORNL

    2009-07-01

    Biomass particle size impacts handling, storage, conversion, and dust control systems. Size reduction mechanical energy was directly measured for switchgrass (Panicum virgatum L.), wheat straw (Triticum aestivum L.), and corn stover (Zea mays L.) in an instrumented hammer mill. Direct energy inputs were determined for hammer mill operating speeds from 2000 to 3600 rpm for 3.2 mm integral classifying screen and mass input rate of 2.5 kg/min with 90 - and 30 -hammers. Overall accuracy of specific energy measurement was calculated as 0.072 MJ/Mg. Particle size distributions created by hammer mill were determined for mill operating factors using ISO sieve sizes from 4.75 to 0.02 mm in conjunction with Ro-Tap sieve analyzer. A wide range of analytical descriptors were examined to mathematically represent the range of particle sizes in the distributions. Total specific energy (MJ/Mg) was defined as size reduction energy to operate the hammer mill plus that imparted to biomass. Effective specific energy was defined as energy imparted to biomass. Total specific energy for switchgrass, wheat straw, and corn stover grinding increased by 37, 30, and 45% from 114.4, 125.1, and 103.7 MJ/Mg, respectively, with an increase in hammer mill speed from 2000 to 3600 rpm for 90 -hammers. Corresponding total specific energy per unit size reduction was 14.9, 19.7, and 13.5 MJ/Mg mm, respectively. Effective specific energy of 90 -hammers decreased marginally for switchgrass and considerably for wheat straw and it increased for corn stover with an increase in speed from 2000 to 3600 rpm. However, effective specific energy increased with speed to a certain extent and then decreased for 30 -hammers. Rosin Rammler equation fitted the size distribution data with R2 > 0.995. Mass relative span was greater than 1, which indicated a wide distribution of particle sizes. Hammer milling of switchgrass, wheat straw, and corn stover with 3.2 mm screen resulted in well-graded fine-skewed mesokurtic

  6. Investigation of magnetic properties of MnZn-substituted strontium ferrite nanopowders prepared via conventional ceramic technique followed by a high energy ball milling

    Science.gov (United States)

    Arab, A.; Mardaneh, M. R.; Yousefi, M. H.

    2015-01-01

    Strontium ferrite powders with substitution of Mn2+ and Zn2+ ions for Fe3+ ions according to the formula SrMnxZnxFe12-2xO19, wherein x ranging from 0 to 1 with a step of 0.2, has been pre-milled via conventional ceramic method and calcined at 1200 °C for 4 h in the air. In order to get nanopowders, the obtained powders were milled again in a high energy SPEX mill for 1 h and 15 min. XRD study was performed to investigation the phases and structural properties of samples. Lattice parameters and mean crystallite sizes of the milled powders were determined from the XRD data and Scherrer's formula. Size of particles was studied by TEM. The DC electrical resistivities of the milled samples have been measured by the two-point probe method. In addition, room temperature magnetizations and coercivities of the samples in a magnetic field of 14.7 kOe have been determined from the hysteresis loops. The behavior of magnetizations of samples has been discussed based on core-shell model and according to the site occupation of substituted cations on the sublattices. The discussion of site occupation also supports the increase of lattice parameters as x increases.

  7. Effect of Annealing to the Formation of The 123 Phase YBa2Cu3O7-x Superconductor Produced by High Energy Milling

    International Nuclear Information System (INIS)

    Didin S Winatapura; Yustinus P, Wisnu A.A; Sukirman, E.

    2008-01-01

    Effect of annealing to the formation of 123 phase YBa 2 Cu 3 O 7-x superconductor produced by high energy milling (HEM) has been investigated. The milling process by using HEM method was performed for 30 hours, and followed by annealing at 500 o C, 600 o C, and 700 o C for 10 hours. The phase quality and quantity inside the specimen was measured by X-rays diffraction technique (XRD), and analyzed using Rietveld method. The microstructure of the specimen was observed with Scanning Electron Microscope (SEM), and electric property of the specimen was measured with four point probe. The result showed that the milling for 30 hours caused the deformation and partial decomposition of 123 phase resulting in another phase. The anneal effect caused the recrystallization process of decomposed 123 phase in such away that reformed 123 phase having finer crystallite size. According to the calculation using the Hall-Williamson's equation, the diameter of the crystallite size, D was obtained of about 496 Armstrong for milled specimen, and D ∼ 1,714 Armstrong for sintered specimen. By decreasing the 123 phase grain size, the intergrain contact surface became larger. It means that the intergrain link of 123 phase became stronger. The critical current (density) of milled specimen was obtained as J c ∼23.74 A.cm -2 , and J c ∼ 3.18 A.cm -2 for sintered specimen. Thus, the transport current that flowed intergrain inside 123 phase increased.(author)

  8. Use of high energy ball milling to study the role of graphene nanoplatelets and carbon nanotubes reinforced magnesium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Rashad, Muhammad, E-mail: rashadphy87@gmail.com [College of Materials Science and Engineering, Chongqing University, Chongqing 400044 (China); National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044 (China); Pan, Fusheng, E-mail: fspan@cqu.edu.cn [College of Materials Science and Engineering, Chongqing University, Chongqing 400044 (China); National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044 (China); Chongqing Academy of Science and Technology, Chongqing, Chongqing 401123 (China); Zhang, Jianyue [College of Materials Science and Engineering, Chongqing University, Chongqing 400044 (China); National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044 (China); Asif, Muhammad [School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024 (China)

    2015-10-15

    Graphene nanoplatelets (few layer graphene) and carbon nanotubes were used as reinforcement fillers to enhance the mechanical properties of AZ31 magnesium alloy through high energy ball milling, sintering, and hot extrusion techniques. Experimental results revealed that tensile fracture strain of AZ31 magnesium alloy was enhanced by +49.6% with 0.3 wt.% graphene nanoplatelets compared to −8.3% regression for 0.3 wt.% carbon nanotubes. The tensile strength of AZ31 magnesium alloy was decreased (−11.2%) with graphene nanoplatelets addition, while increased (+7.7%) with carbon nanotubes addition. Unlike tensile test, compression tests showed different trend. The compression strength of carbon nanotubes-AZ31 composite was +51.2% greater than AZ31 magnesium alloy as compared to +0.6% increase for graphene nanoplatelets. The compressive fracture strain of carbon nanotubes-AZ31 composite was decreased (−14.1%) while no significant change in fracture strain of graphene nanoplatelets-AZ31 composite was observed. The X-ray diffraction results revealed that addition of reinforcement particles weaken the basal textures which affect the composite's yield asymmetry. Microstructure evaluation revealed the absence of intermetallic phase formation between reinforcements and matrix. The carbon reinforcements in AZ31 magnesium alloy dissolve and isolate β phases throughout the matrix. The increased fracture strain and mechanical strength of graphene nanoplatelets and carbon nanotubes-AZ31 composites are attributed to large specific surface area of graphene nanoplatelets and stiffer nature of carbon nanotubes respectively. - Highlights: • Powder metallurgy method was used to fabricate magnesium composites. • The AZ31-carbon materials composite were blended using ball milling. • The reinforcement particles weaken the basal texture which affects yield asymmetry of composites. • AZ31-graphene nanoplatelets composite exhibited impressive increase in tensile elongation

  9. Interpretation of Fermion system equilibration by energy fluid motion

    International Nuclear Information System (INIS)

    Jang, S.

    1990-01-01

    We study the equilibration of fermion system with the help of both linear and non-linear master equations which are originated from the extended time-dependent Hartree-Fock equation of motion. We show how the non-linear master equation for nucleon occupation number transforms into the Navier-Stokes type of one dimensional equation for non-stationary flow of a compressible and viscous fluid. Physical consequences of these equations are investigated by providing illustrative examples

  10. Energy Consumption and Indoor Environment Predicted by a Combination of Computational Fluid Dynamics and Building Energy Performance Simulation

    DEFF Research Database (Denmark)

    Nielsen, Peter Vilhelm

    2003-01-01

    An interconnection between a building energy performance simulation program and a Computational Fluid Dynamics program (CFD) for room air distribution is introduced for improvement of the predictions of both the energy consumption and the indoor environment.The article describes a calculation...

  11. Estimation of numerical uncertainty in computational fluid dynamics simulations of a passively controlled wave energy converter

    DEFF Research Database (Denmark)

    Wang, Weizhi; Wu, Minghao; Palm, Johannes

    2018-01-01

    mathematical models such as computational fluid dynamics are preferred and over the last 5 years, computational fluid dynamics has become more frequently used in the wave energy field. However, rigorous estimation of numerical errors, convergence rates and uncertainties associated with computational fluid...... for almost linear incident waves. First, we show that the computational fluid dynamics simulations have acceptable agreement to experimental data. We then present a verification and validation study focusing on the solution verification covering spatial and temporal discretization, iterative and domain......The wave loads and the resulting motions of floating wave energy converters are traditionally computed using linear radiation–diffraction methods. Yet for certain cases such as survival conditions, phase control and wave energy converters operating in the resonance region, more complete...

  12. Fluid calories and energy balance: the good, the bad, and the uncertain.

    Science.gov (United States)

    Mattes, R

    2006-08-30

    Energy-yielding fluids are a large and growing proportion of daily energy intake. The specific form and nutrient composition of fluids may hold divergent implications for energy balance. Ethanol elicits a weak compensatory dietary response, resulting in positive energy balance. However, its impact on body weight is unclear, possibly due to metabolic inefficiencies. In contrast, the weak dietary compensation for clear beverages containing other energy sources is associated with weight gain. How these beverages elude satiety mechanisms has not been studied. Soups hold higher satiating value, at least in part, due to cognitive factors. Nutrient dense beverages have been used successfully in meal replacement regimens for weight management, but due to their relatively weak satiety value, are widely consumed for weight gain and as nutrient supplements. A better understanding of the role of fluid calories in the diet is needed to improve dietary guidelines.

  13. Estimating Energy Consumption of Mobile Fluid Power in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Lynch, Lauren [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Zigler, Bradley T. [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-02

    This report estimates the market size and energy consumption of mobile off-road applications utilizing hydraulic fluid power, and summarizes technology gaps and implementation barriers. Mobile fluid power is the use of hydraulic fluids under pressure to transmit power in mobile equipment applications. The mobile off-road fluid power sector includes various uses of hydraulic fluid power equipment with fundamentally diverse end-use application and operational requirements, such as a skid steer loader, a wheel loader or an agriculture tractor. The agriculture and construction segments dominate the mobile off-road fluid power market in component unit sales volume. An estimated range of energy consumed by the mobile off-road fluid power sector is 0.36 - 1.8 quads per year, which was 1.3 percent - 6.5 percent of the total energy consumed in 2016 by the transportation sector. Opportunities for efficiency improvements within the fluid power system result from needs to level and reduce the peak system load requirements and develop new technologies to reduce fluid power system level losses, both of which may be facilitated by characterizing duty cycles to define standardized performance test methods. There are currently no commonly accepted standardized test methods for evaluating equipment level efficiency over a duty cycle. The off-road transportation sector currently meets criteria emissions requirements, and there are no efficiency regulations requiring original equipment manufacturers (OEM) to invest in new architecture development to improve the fuel economy of mobile off-road fluid power systems. In addition, the end-user efficiency interests are outweighed by low equipment purchase or lease price concerns, required payback periods, and reliability and durability requirements of new architecture. Current economics, low market volumes with high product diversity, and regulation compliance challenge OEM investment in commercialization of new architecture development.

  14. Chemical composition and metabolizable energy values of corn germ meal obtained by wet milling for layers

    Directory of Open Access Journals (Sweden)

    CS Albuquerque

    2014-03-01

    Full Text Available An experiment was carried out to determine the chemical composition, metabolizable energy values, and coefficients of nutrient digestibility of corn germ meal for layers. The chemical composition of corn germ meal was determined, and then a metabolism assay was performed to determine its apparent metabolizable energy (AME and apparent metabolizable energy corrected for nitrogen (AMEn values and its dry matter and gross energy apparent metabolizability coefficients (CAMDM and CAMGE, respectively. In the 8-day assay (four days of adaptation and four days of total excreta collection, 60 29-week-old white Lohman LSL layers were used. A completely randomized experimental design, with three treatments with five replicates of four birds each, was applied. Treatments consisted of a reference diet and two test diets, containing 20 or 30% corn germ meal. Results were submitted to analysis of variance and means were compared by the Tukey tests at 5% probability level. The chemical composition of corn germ meal was: 96.39% dry matter, 49.48% ether extract, 1.87% ashes, 7243 kcal gross energy/kg, 11.48% protein, 0.19% methionine, 0.21% cystine, 0.48% lysine, 0.40% threonine, 0.72% arginine, 0.35% isoleucine, 0.83% leucine, 0.57% valine, and 0.37% histidine, on as-fed basis. There were no statistical differences in AME, AMEn, CAMDM, and CAMGE values with the inclusion of 20 and 30% corn germ meal in the diets. On dry matter basis, AME, AMEn, CAMDM, and CAMGE values of corn germ meal were: 4,578 and 4,548 kcal/kg, 4,723 and 4,372 kcal/kg, 64.95 and 61.86%, respectively.

  15. Thirteenth symposium on energy engineering sciences: Proceedings. Fluid/thermal processes, systems analysis and control

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-11-01

    The DOE Office of Basic Energy Sciences, of which Engineering Research is a component program, is responsible for the long-term mission-oriented research in the Department. Consistent with the DOE/BES mission, the Engineering Research Program is charged with the identification, initiation, and management of fundamental research on broad, generic topics addressing energy-related engineering problems. Its stated goals are: (1) to improve and extend the body of knowledge underlying current engineering practice so as to create new options for enhancing energy savings and production, for prolonging useful life of energy-related structures and equipment, and for developing advanced manufacturing technologies and materials processing with emphasis on reducing costs with improved industrial production and performance quality; and (2) to expand the store of fundamental concepts for solving anticipated and unforeseen engineering problems in the energy technologies. The meeting covered the following areas: (1) fluid mechanics 1--fundamental properties; (2) fluid mechanics 2--two phase flow; (3) thermal processes; (4) fluid mechanics 3; (5) process analysis and control; (6) fluid mechanics 4--turbulence; (7) fluid mechanics 5--chaos; (8) materials issues; and (9) plasma processes. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  16. Energy balances and greenhouse gas emissions of crude palm oil production system in Indonesia (Case study: Mill P, PT X, Sumatera Island)

    Science.gov (United States)

    Andarani, Pertiwi; Nugraha, Winardi Dwi; Wieddya

    2017-03-01

    Indonesia is one of the largest palm oil producers in the world. The total exported crude palm oil (CPO) and its derivatives in 2015 reached about 26.40 million tons or increase at 21% compared to the previous year (2014). However, the further expansion of the CPO production system could potentially have environmental impacts. The objective of this study is to analyze the energy balances and greenhouse gas emissions at mill P, PT X located in Sumatera Island. System analysis approaches was applied to this study and the assessment was focused on a CPO production system in PT XYZ located on the Sumatera Island. The system boundary was determined based on the field study. The data collection consisted of all the input and output energy which involving all input materials (including fertilizers, herbicides, pesticides, water, etc.) and energy consumption (consumption of diesel, electricity, etc.) starting from plantation activities (at the oil palm plantation) to the conversion process (at the palm oil mill). The energy output from biodiesel was 480.46 GJ/ha (2014) and decreased to 450.79 GJ/ha (2015). Surplus energy from biogas was 15.21 GJ/ha (2014) and 13.57 GJ/ha (2015). The NEP was 494.56 GJ/ha and decreased to 317.84 GJ/ha. Meanwhile, the NER decreased from 3.27 (2014) to 3.17 (2015). The NEP in this mill is significantly higher than other related studies of similar palm oil production system in other companies. The emission of the activities in the palm estate increased from 12.50 kgCO2eq/ton FFB to 22.057 kgCO2eq/ton FFB. In the palm oil mill, the emission decreased from 2,509.93 kgCO2eq/ton CPO to 2,057.14 kgCO2eq/ton CPO.

  17. Two Fluid Scenario for Dark Energy Model in a Scalar-Tensor Theory of Gravitation

    Science.gov (United States)

    Reddy, D. R. K.; Santhi Kumar, R.

    2013-04-01

    In this paper, we investigate the evolution of dark energy parameter in the spatially homogeneous and isotropic Friedmann-Robertson-Walker (FRW) model filled with barotropic fluid and dark energy in the framework of scalar-tensor theory of gravitation formulated by Saez and Ballester (Phys. Lett. A 113:467, 1986). To obtain a determinate solution special law of variation for Hubble's parameter proposed by Bermann (Nuovo Cimento B 74:183, 1983) is used. We consider the two cases of interacting and non-interacting fluid (barotropic and dark energy) scenario and obtained general results. The physical aspects of the results obtained are also discussed.

  18. Local shell-to-shell energy transfer via nonlocal interactions in fluid ...

    Indian Academy of Sciences (India)

    in a triad, and the energy exchanges between wave-number shells in incompressible fluid turbulence. The computation has been done using first-order perturbative field theory. In three dimensions, magnitude of triad interactions is large for nonlocal triads, and small for local triads. However, the shell-to-shell energy transfer ...

  19. Phenolic compounds removal from mimosa tannin model water and olive mill wastewater by energy-efficient electrocoagulation process

    Directory of Open Access Journals (Sweden)

    Marijana Kraljić Roković

    2014-12-01

    Full Text Available The objective of this work was to study the influence of NaCl concentration, time, and current density on the removal efficiency of phenolic compounds by electrocoagulation process, as well as to compare the specific energy consumption (SEC of these processes under different experimental conditions. Electrocoagulation was carried out on two different samples of water: model water of mimosa tannin and olive mill wastewater (OMW. Low carbon steel electrodes were used in the experiments. The properties of the treated effluent were determined using UV/Vis spectroscopy and by measuring total organic carbon (TOC. Percentage of removal increased with time, current density, and NaCl concentration. SEC value increased with increased time and current density but it was decreased significantly by NaCl additions (0-29 g L-1. It was found that electro­coagulation treatment of effluents containing phenolic compounds involves complex formation between ferrous/ferric and phenolic compounds present in treated effluent, which has significant impact on the efficiency of the process.

  20. Preparation of magnetite nanoparticles by high-energy planetary ball mill and its application for ciprofloxacin degradation through heterogeneous Fenton process.

    Science.gov (United States)

    Hassani, Aydin; Karaca, Melike; Karaca, Semra; Khataee, Alireza; Açışlı, Özkan; Yılmaz, Bilal

    2018-04-01

    In this study, the heterogeneous Fenton oxidation of ciprofloxacin (CIP) in an aqueous solution was examined over the nano-sized magnetite (Fe 3 O 4 ) as a catalyst supplied through high-energy planetary ball milling process. To characterize the magnetite samples after and before ball milling operation, the X-ray diffraction (XRD), High-resolution scanning electron microscopy (HR-SEM), energy-dispersive X-ray spectroscopy (EDX), Brunauer-Emmett-Teller (BET) and Fourier transform infrared spectroscopy (FTIR) analysis were applied. The catalytic properties of the magnetite were considerably improved because of the enhancement in its physical properties, resulted from milling process. The findings also indicated that 6 h ball-milled magnetite demonstrated better properties for elimination of CIP of about 89% following 120 min reaction at optimal conditions of H 2 O 2 12 mM, Fe 3 O 4 1.75 g L -1 , CIP 10 mg L -1 and pH 3.0. The effects of various operational parameters, including the initial pH of the solution, H 2 O 2 initial concentration, catalyst dosage, milling time and CIP initial concentration was investigated. Application of organic and inorganic scavengers considerably decreased the CIP removal efficiency. Correspondingly, with respect to the leached iron values at pH 3, it was concluded that CIP elimination was mainly occurred through heterogeneous Fenton procedure. This process included the adsorption and oxidation phases in which the hydroxyl radicals (OH) played a significant role. GC-MS analysis was used for recording of the generated intermediates of the CIP removal in the course of heterogeneous Fenton process. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Energy Measurement with the ATLAS Electromagnetic Calorimeter at the Per Mill Accuracy Level

    CERN Document Server

    Teischinger, Florian; Fabjan, Christian

    The ATLAS experiment is designed to study the proton-proton collisions produced at the Large Hadron Collider (LHC) at CERN. It is made up of various sub-detectors to measure the properties of all the particles produced at the proton-proton collision. Over the last three years of running around 20 x 10^14 collisions of proton data have been recorded. Liquid argon (LAr) sampling calorimeters are used for all electromagnetic calorimetry and for hadronic calorimetry in the end-caps. The Inner Detector, on the other hand, measures the transverse momentum of charged particles down to a momentum of 0.5 GeV. This thesis deals with the absolute measurement of the energy in the electromagnetic calorimeter and the improvement of the systematic uncertainties. A method using the ratio of the energy E in the calorimeter and the momentum measurement p in the Inner Detector (E/p) was used to extract the energy scale of the electromagnetic LAr calorimeter for electrons and positrons. To investigate and further reduce the syst...

  2. Molten salts activated by high-energy milling: A useful, low-temperature route for the synthesis of multiferroic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Hernández-Ramírez, Anayantzin; Martínez-Luévanos, Antonia [Facultad de Ciencias Químicas, Universidad Autónoma de Coahuila, V. Carranza s/n, Saltillo, Coahuila 25280 (Mexico); Fuentes, Antonio F. [CINVESTAV Unidad Saltillo, Apdo. Postal 663, Saltillo, Coahuila 25000 (Mexico); Earth and Environmental Science, University of Michigan, 3514 C.C. Little Building, 1100 N. University Avenue, Ann Arbor, MI 48109-1005 (United States); Nelson, Anna-Gay D.; Ewing, Rodney C. [Earth and Environmental Science, University of Michigan, 3514 C.C. Little Building, 1100 N. University Avenue, Ann Arbor, MI 48109-1005 (United States); Montemayor, Sagrario M., E-mail: smmontemayor@gmail.com [Facultad de Ciencias Químicas, Universidad Autónoma de Coahuila, V. Carranza s/n, Saltillo, Coahuila 25280 (Mexico); Earth and Environmental Science, University of Michigan, 3514 C.C. Little Building, 1100 N. University Avenue, Ann Arbor, MI 48109-1005 (United States)

    2014-01-25

    Highlights: • The synthesis route purposed demonstrates the formation of BiFeO{sub 3} at only 500 °C. • The magnetic and ferroelectric properties are comparable to those of bulk BiFeO{sub 3}. • By this route, several phases in Bi{sub 1−x}La{sub x}FeO{sub 3} system are obtained at only 500 °C. • The route developed here could be useful to synthesize other perovskite-type oxides. -- Abstract: There are only a few multiferroic compounds, among which BiFeO{sub 3} is the most important. Research the synthesis of bismuth ferrite, with novel and improved magnetic and electrical properties, has been mainly based on the use of hydrothermal or sol gel methods. However, these methods require either rather extreme conditions or several steps for synthesis. We demonstrate that the use of molten salts, activated by high energy milling, results in pure nanometric BiFeO{sub 3}, LaFeO{sub 3} and intermediate phases in the Bi{sub 1−x}La{sub x}FeO{sub 3} system. The chemical reagents used are Bi(NO{sub 3}){sub 3}⋅5H{sub 2}O, La(NO{sub 3}){sub 3}⋅6H{sub 2}O, Fe(NO{sub 3}){sub 3}⋅9H{sub 2}O and NaOH. A brief milling process of the reagents creates an amorphous precursor and crystalline NaNO{sub 3}. The thermal treatment of the precursors, at 500 °C for two hours, produces a crystalline mixture of Bi{sub 1−x}La{sub x}FeO{sub 3} and NaNO{sub 3}. Simple washing eliminates the NaNO{sub 3}. The characterization of intermediates and final products, through thermal analysis, X-ray diffraction and scanning electronic microscopy, allows the inference of possible mechanism. In addition, vibrating sample magnetometry (VSM) and ferroelectric tests show the typical magnetic and electric polarization loops characteristic of these materials even when formed at the nano-scale.

  3. Uranium mill tailings

    International Nuclear Information System (INIS)

    McLaren, L.H.

    1982-11-01

    This bibliography contains information on uranium mill tailings included in the Department of Energy's Energy Data Base from January 1981 through October 1982. The abstracts are grouped by subject category as shown in the table of contents. Entries in the subject index also facilitate access by subject, e.g., Mill Tailings/Radiation Hazards. Within each category the arrangement is by report number for reports, followed by nonreports in reverse chronological order. These citations are to research reports, journal articles, books, patents, theses, and conference papers from worldwide sources. Five indexes, each preceded by a brief description, are provided: Corporate Author, Personal Author, Subject, Contract Number, and Report Number. (335 abstracts)

  4. Symmetric energy-momentum tensor in Maxwell, Yang-Mills, and Proca theories obtained using only Noether's theorem

    Energy Technology Data Exchange (ETDEWEB)

    Montesinos, M. [CINVESTAV-IPN, 07360 Mexico D.F. (Mexico); Flores, E. [Facultad de Fisica e Inteligencia Artificial, Universidad Veracruzana, 91000 Xalapa, Veracruz (Mexico)]. E-mail: merced@fis.cinvestav.mx

    2006-07-01

    The symmetric and gauge-invariant energy-momentum tensors for source-free Maxwell and Yang-Mills theories are obtained by means of translations in spacetime via a systematic implementation of Noether's theorem. For the source-free neutral Proca field, the same procedure yields also the symmetric energy-momentum tensor. In all cases, the key point to get the right expressions for the energy-momentum tensors is the appropriate handling of their equations of motion and the Bianchi identities. It must be stressed that these results are obtained without using Belinfante's symmetrization techniques which are usually employed to this end. (Author)

  5. Dark energy from cosmological fluids obeying a Shan-Chen non-ideal equation of state

    OpenAIRE

    Bini, Donato; Geralico, Andrea; Gregoris, Daniele; Succi, Sauro

    2014-01-01

    We consider a Friedmann-Robertson-Walker universe with a fluid source obeying a nonideal equation of state with ‘‘asymptotic freedom,’’ namely ideal gas behavior (pressure changes directly proportional to density changes) both at low and high density regimes, following a fluid dynamical model due to Shan and Chen. It is shown that, starting from an ordinary energy density component, such fluids naturally evolve towards a universe with a substantial ‘‘dark energy’’ component at the present tim...

  6. Effect of Surfactant Molecular Weight on Particle Morphology of SmCo5 Prepared by High Energy Ball Milling

    Science.gov (United States)

    2014-04-01

    milling media, and milling time provides a high level of control over the product morphology, particle size , grain- size , interfacial surface area, and...specific surface area.1 HEBM has been employed within the magnetic materials community as a method for producing rare-earth magnetic nanoparticles ...surfactant molecules bind to these new surfaces result- ing in the formation of a thin organic layer that protects the exposed surface from cold welding when

  7. Development of an Energy Biorefinery Model for Chestnut (Castanea sativa Mill. Shells

    Directory of Open Access Journals (Sweden)

    Alessandra Morana

    2017-09-01

    Full Text Available Chestnut shells (CS are an agronomic waste generated from the peeling process of the chestnut fruit, which contain 2.7–5.2% (w/w phenolic compounds and approximately 36% (w/w polysaccharides. In contrast with current shell waste burning practices, this study proposes a CS biorefinery that integrates biomass pretreatment, recovery of bioactive molecules, and bioconversion of the lignocellulosic hydrolyzate, while optimizing materials reuse. The CS delignification and saccharification produced a crude hydrolyzate with 12.9 g/L of glucose and xylose, and 682 mg/L of gallic acid equivalents. The detoxification of the crude CS hydrolyzate with 5% (w/v activated charcoal (AC and repeated adsorption, desorption and AC reuse enabled 70.3% (w/w of phenolic compounds recovery, whilst simultaneously retaining the soluble sugars in the detoxified hydrolyzate. The phenols radical scavenging activity (RSA of the first AC eluate reached 51.8 ± 1.6%, which is significantly higher than that of the crude CS hydrolyzate (21.0 ± 1.1%. The fermentation of the detoxified hydrolyzate by C. butyricum produced 10.7 ± 0.2 mM butyrate and 63.9 mL H2/g of CS. Based on the obtained results, the CS biorefinery integrating two energy products (H2 and calorific power from spent CS, two bioproducts (phenolic compounds and butyrate and one material reuse (AC reuse constitutes a valuable upgrading approach for this yet unexploited waste biomass.

  8. Energy and protein production from pulp mill wastes. Final report, 15 Jun 1976-14 Jun 1979

    Energy Technology Data Exchange (ETDEWEB)

    Jurgensen, M.F.; Patton, J.T.

    1979-06-14

    The goal of this research was to convert the organics and sulfur in sulfite spent liquor (SSL) now classified as pollutants from sulfite pulp mills, into synthetic methane and protein by means of a combination chemical-biological process. Ozonization was used to break the high molecular weight lignosulfonate molecules present in SSL into lower weight fractions which could be metabolized by methane-producing bacteria and protein-producing yeast. Ozonization experiments showed that this treatment is effective in partially oxidizing and fragmenting lignosulfonates into fermentable substrates. This process is initiated at low ozone concentrations and proceeds rapidly until nearly 30% of the Chemical Oxygen Demand (COD) has been consumed. The conditions under which ozonization is conducted greatly affect the degree of oxidation and the molecular weight of the cleaved fragments. In spite of the appreciable oxidative cleavage of the lignosulfonate molecules, continuous-flow fermentation studies showed rather low yields of methane and yeast from ozonated SSL. Under optimum conditions, methane production averaged only 1.7 1/1 of SSL or approximately 3% of the total organics present. Protein production was somewhat more favorable with 6% of the organics being converted to yeast biomass. (6g/1). Neither fermentation fully used all of the oxygenated fragments produced by ozonization, and thus, a two-stage process might yield better results. Although it appears that ozonization is not a viable treatment of SSL under present economic conditions, with increased demand for energy and protein, it could become more competitive in the future. However, of possibly greater importance is the potential use of partial oxidation treatments to improve the biodegradability of organic wastes.

  9. Microstructure and mechanical properties of nanocrystalline high strength Al-Mg-Si (AA6061) alloy by high energy ball milling and spark plasma sintering

    International Nuclear Information System (INIS)

    Rana, Jatinkumar Kumar; Sivaprahasam, D.; Seetharama Raju, K.; Subramanya Sarma, V.

    2009-01-01

    In the present paper, the microstructure and mechanical properties of nanostructured Al-Mg-Si based AA6061 alloy obtained by high energy ball milling and spark plasma sintering were reported. Gas atomized microcrystalline powder of AA6061 alloy was ball milled under wet condition at room temperature to obtain nanocrystalline powder with grain size of ∼30 nm. The nanocrystalline powder was consolidated to fully dense compacts by spark plasma sintering (SPS) at 500 deg. C. The grain size after SPS consolidation was found to be ∼85 nm. The resultant SPS compacts exhibited microhardness of 190-200 HV 100g , compressive strength of ∼800 MPa and strain to fracture of ∼15%.

  10. Hyperfine, structural and electrical transport properties of the high-energy milled (1 - X).ZnO-X.FeO system

    Energy Technology Data Exchange (ETDEWEB)

    Reisdoerfer, E. C.; Ivashita, F. F., E-mail: Fivashita@yahoo.com.br; Bellini, J. V.; Paesano, A. [UEM, Departamento de Fisica (Brazil); Costa, A. C. S. da [UEM, Departamento de Agronomia (Brazil); Pianaro, S. A. [UEPG, Departamento de Engenharia de Materiais (Brazil); Hallouche, B. [UNISC, Departamento de Quimica e Fisica (Brazil)

    2010-01-15

    The system (1 - X).ZnO+X.FeO was high-energy ball-milled for 24 h and characterized by X-ray diffraction and Moessbauer spectroscopy. Sintered pellets were also prepared for X {<=} 0.07 by further thermal annealing pressed milled samples. These samples were also characterized regarding their I-V behavior. The results revealed the monophase formation of a (Zn{sub 1-X}Fe{sub X})O solid solution isomorphous to the zincite and a spinel-like phase of the Zn{sub 1-Y}Fe{sub 2+Y}O{sub 4} type. The sintered samples showed I-V curves typical of poor varistor systems and the resistivity increasing with X.

  11. Influence of B4C-doping and high-energy ball milling on phase formation and critical current density of (Bi,Pb)-2223 HTS

    Science.gov (United States)

    Margiani, N. G.; Mumladze, G. A.; Adamia, Z. A.; Kuzanyan, A. S.; Zhghamadze, V. V.

    2018-05-01

    In this paper, the combined effects of B4C-doping and planetary ball milling on the phase evolution, microstructure and transport properties of Bi1.7Pb0.3Sr2Ca2Cu3Oy(B4C)x HTS with x = 0 ÷ 0.125 were studied through X-ray diffraction (XRD), scanning electron microscopy (SEM), resistivity and critical current density measurements. Obtained results have shown that B4C additive leads to the strong acceleration of high-Tc phase formation and substantial enhancement in Jc. High-energy ball milling seems to produce a more homogeneous distribution of refined doped particles in the (Bi,Pb)-2223 HTS which results in an improved intergranular flux pinning and better self-field Jc performance.

  12. High energy milling of zirconia-titania powders synthesized by coprecipitation; Moagem de alta energia em pos de zirconia-titania sintetizados por co-precipitacao

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Cristiano M.B.; Marchi, Juliana; Lazar, Dolores R.R.; Ussui, Valter, E-mail: vussui@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2009-07-01

    Zirconia based ceramics are known by its remarkable mechanical properties as hardness and fracture toughness and in biomedical applications are classified as bioinert. By its turn, titania ceramics has been studied due to its ability to bond directly to bone tissue, but are structurally brittle. Properties of ceramics are strongly dependent of physical and chemical characteristics of its former powders. In the present work, research done for the synthesis of zirconia-titania ceramics by the coprecipitation route are presented, emphasizing the conditioning process through a high energy milling in a atritor mill, classifying of powders in vibratory sieves and forming of cylindrical ceramic samples followed by a sintering process at 1500 deg C for 01 hour. The intermediary samples produced in the various steps of the process were characterized by scanning electronic microscope, X-ray diffraction, nitrogen gas adsorption and granulometric analysis. (author)

  13. A structural investigation of SmCo5/Fe nanostructured alloys obtained by high-energy ball milling and subsequent annealing

    International Nuclear Information System (INIS)

    Le Breton, J M; Larde, R; Chiron, H; Pop, V; Givord, D; Isnard, O; Chicinas, I

    2010-01-01

    SmCo 5 /Fe nanostructured alloys with 20 wt% Fe, obtained by high-energy ball milling of SmCo 5 and Fe powders, were investigated by 57 Fe Moessbauer spectrometry, x-ray diffraction and tomographic atom probe. The Moessbauer analysis reveals that during the first stages of milling, an interdiffusion of Co and Fe occurs, leading both to the formation of α-Fe(Co) regions in α-Fe and to the introduction of Fe in SmCo 5 regions. Annealing at temperatures up to 650 0 C for 0.5 h promotes interdiffusion further leading to the formation of a unique α-Fe(Co) phase and a Fe-richer Sm(Co,Fe) 5 phase. The Co/Fe interdiffusion is confirmed by tomographic atom probe analysis. The data are discussed and compared with the results of previous magnetic measurements.

  14. Morphology and magnetic properties of CeCo{sub 5} submicron flakes prepared by surfactant-assisted high-energy ball milling

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, J.J.; Gao, H.M.; Yan, Y.; Bai, X.; Su, F.; Wang, W.Q. [State key Laboratory for Superhard Materials and Department of Physics, Jilin University, Changchun 130012 (China); Du, X.B., E-mail: duxb@jlu.edu.cn [State key Laboratory for Superhard Materials and Department of Physics, Jilin University, Changchun 130012 (China)

    2012-10-15

    CeCo{sub 5} permanent magnetic alloy has been processed by surfactant assisted high energy ball milling. Heptane and oleic acid were used as the solvent and surfactant, respectively. The amount of surfactant used was 50% by weight of the starting powder. The produced particles were deposited on a piece of copper (4 mm in length and width) under a magnetic field of 27 kOe applied along the copper surface and immobilized by ethyl {alpha}-cyanoacrylate. Scanning electron microscope pictures show that the particles are flakes, several {mu}m in length and width and tens of nm in thickness. X-ray diffraction patterns and magnetic measurements prove that the flakes are crystalline with c-axes magnetic anisotropy. The easy magnetization axis is oriented perpendicular to the surface of the flake. A maximum coercivity of 3.3 kOe was obtained for the sample milled for 40 min. - Highlights: Black-Right-Pointing-Pointer CeCo{sub 5} permanent magnetic alloy has been processed by surfactant assisted high energy ball milling (HEBM). Black-Right-Pointing-Pointer The particles show a flake-like morphology with several {mu}m in length and width and tens nm in thickness. Black-Right-Pointing-Pointer The flakes are crystallographic and magnetic anisotropic and the c-axes, also the easy magnetization directions are oriented perpendicular to the surface of the flake. Black-Right-Pointing-Pointer Maximum coercivity of 3.3 kOe has been obtained for the sample milled for 40 min.

  15. A novel fabrication technology of in situ TiB2/6063Al composites: High energy ball milling and melt in situ reaction

    International Nuclear Information System (INIS)

    Zhang, S.-L.; Yang, J.; Zhang, B.-R.; Zhao, Y.-T.; Chen, G.; Shi, X.-X.; Liang, Z.-P.

    2015-01-01

    Highlights: • This paper presents a novel technology to fabricate the TiB 2 /6063Al composites. • The novel technology decreases in situ reaction temperature and shortens the time. • The reaction mechanism of in situ reaction at the low temperature is discussed. • Effect of ball milling time and in situ reaction time on the composites is studied. - Abstract: TiB 2 /6063Al matrix composites are fabricated from Al–TiO 2 –B 2 O 3 system by the technology combining high energy ball milling with melt in situ reaction. The microstructure and tensile properties of the composites are investigated by XRD, SEM, EDS, TEM and electronic tensile testing. The results indicate that high energy ball milling technology decreases the in situ reaction temperature and shortens the reaction time for Al–TiO 2 –B 2 O 3 system in contrast with the conventional melt in situ synthesis. The morphology of in situ TiB 2 particles is exhibited in irregular shape or nearly circular shape, and the average size of the particles is less than 700 nm, thereinto the minimum size is approximately 200 nm. In addition, the morphology and size of the reinforced particles are affected by the time of ball milling and in situ reaction. TEM images indicate that the interface between 6063Al matrix and TiB 2 particles is clear and no interfacial outgrowth is observed. Tensile testing results show that the as-cast TiB 2 /6063Al composites exhibit a much higher strength, reaching 191 MPa, which is 1.23 times as high as the as-cast 6063Al matrix. Besides, the tensile fracture surface of the composites displays the dimple-fracture character

  16. On some properties of Einstein equations with the perfect fluid energy-momentum tensor

    International Nuclear Information System (INIS)

    Biesiada, M.; Szydlowski, M.; Szczesny, J.

    1989-01-01

    We discuss the symmetries of Einstein equations with the perfect fluid energy momentum tensor. We show that the symmetries inherited from vacuum equations enforce the equation of state in the form p p 0 = γρ which is the most often used one and contains models with the cosmological constant. 9 refs. (author)

  17. Modelling and simulation of an energy transport phenomenon in a solid-fluid mixture

    International Nuclear Information System (INIS)

    Costa, M.L.M.; Sampaio, R.; Gama, R.M.S. da.

    1989-08-01

    In the present work a model for a local description of the energy transfer phenomenon in a binary (solid-fluid) saturated mixture is proposed. The heat transfer in a saturated flow (through a porous medium) between two parallel plates is simulated by using the Finite Volumes Method. (author) [pt

  18. Plane Symmetric Dark Energy Models in the Form of Wet Dark Fluid ...

    Indian Academy of Sciences (India)

    Abstract. In this paper, we have investigated the plane symmetric space- time with wet dark fluid (WDF), which is a candidate for dark energy, in the framework of f(R, T ) gravity Harko et al. 2011, Phys. Rev. D,. 84, 024020), where R and T denote the Ricci scalar and the trace of the energy–momentum tensor respectively.

  19. Local shell-to-shell energy transfer via nonlocal interactions in fluid ...

    Indian Academy of Sciences (India)

    In this paper we analytically compute the strength of nonlinear interactions in a triad, and the energy exchanges between wave-number shells in incompressible fluid turbulence. The computation has been done using first-order perturbative field theory. In three dimensions, magnitude of triad interactions is large for nonlocal ...

  20. Local shell-to-shell energy transfer via nonlocal interactions in fluid ...

    Indian Academy of Sciences (India)

    August 2005 physics pp. 297–310. Local shell-to-shell energy transfer via nonlocal interactions in fluid turbulence. MAHENDRA K VERMA1, ARVIND AYYER2, OLIVIER ... MS received 1 October 2004; revised 2 March 2005; accepted 13 April 2005 ...... Kraichnan [23,24] first raised the above objection, and proposed.

  1. Energy production rates in fluid mixtures of inelastic rough hard spheres

    OpenAIRE

    Santos, Andrés; Kremer, Gilberto M.; Garzó, Vicente

    2009-01-01

    The aim of this work is to explore the combined effect of polydispersity and roughness on the partial energy production rates and on the total cooling rate of a granular fluid mixture. We consider a mixture of inelastic rough hard spheres of different number densities, masses, diameters, moments of inertia, and mutual coefficients of normal and tangential restitution. Starting from the first equation of the BBGKY hierarchy, the collisional energy production rates associated with the translati...

  2. Energy and water saving measures at the Arloev sugar mill. Final report; Energi- och vattenbesparande aatgaerder vid Arloevs Sockerbruk. Slutrapport

    Energy Technology Data Exchange (ETDEWEB)

    Wamsler, M. [AAF-Processdesign AB, Malmoe (Sweden)

    2001-10-01

    The project comprised several, mutually dependent, sub-projects; mapping, investigation of ways to reduce water consumption, membrane tests aiming to find ways to recover sugar, and pinch analysis to evaluate the possibilities for improved process integration. This final report deals with the overall project results. Identified savings opportunities and savings potentials are presented. The presented measures represent an overall optimisation based on the results of all the project parts. Already during the project, measures have been implemented that are calculated to save 65 000 m{sup 3} water annually, corresponding to 10 % of the total water consumption. This saving is in level with the goals for the project. In the table below, these and additional measures are presented with a total savings potential at approximately 200 000 m{sup 3} /year water. The project will then achieve a saving of just below 35 % of present water consumption. Also in the membrane study the results surpassed the expectations. It was found that with nano filtering a sugar concentration of more than 10 %(W) could be reached in the retentate at a flux 50al/m{sup 2}h. The total sugar losses were less than 5 %, i.e. 95 % should be possible to recover. In total, a savings potential of more than 300 tonnes sugar per year is indicated. The Energy savings in the project are calculated to 7,4 GWh/year, of which 0,2 GWh/year by reduced water consumption, 0,6 GWh/year by water recovery, 1,4 GWh/year by membrane technology and 5,2aGWh/year as a result of process integration. This should be compared to the target 2,5 GWh/year. Hence, the results are almost three times the expected. The savings in monetary terms are estimated at just under SEK 5 million per year. The investment is roughly estimated at between SEK 5 and 6 million, of which SEK 4 million for the membrane equipment and SEK 0,5 million for a process water buffer tank. The remaining investment costs cover heat exchangers, control equipment

  3. Study of magnetic properties of nano-powders prepared by pyrite -> troilite transformation via high energy milling

    DEFF Research Database (Denmark)

    Balaz, P.; Alacova, A.; Godocikova, E.

    2004-01-01

    the formation of troilite FeS together with residual Fe metal after relatively short milling times. The kinetic studies performed by Mossbauer spectrometry and VSM magnetometry enabled us to follow the progress of nanocrystalline magnetic phase formation in more details. It was shown that the pyrite...

  4. Preliminary study on the potential of improving pulp quality and energy efficiency in a South African TMP mills

    CSIR Research Space (South Africa)

    Johakimu, Jonas K

    2010-03-01

    Full Text Available value of freeness (32 ml CSF) for base fraction pulps confirmed the scenario. The second set of trials examined the efficiency of the mill fractionation process in terms of the final pulp quality. The mill’s accept pulps were fractionated. The results...

  5. Energy efficient bead milling of microalgae: Effect of bead size on disintegration and release of proteins and carbohydrates

    NARCIS (Netherlands)

    Postma, P.R.; Suarez Garcia, E.; Safi, Carl; Yonathan, K.; Olivieri, G.; Barbosa, M.J.; Wijffels, R.H.; Eppink, M.H.M.

    2017-01-01

    The disintegration of three industry relevant algae (Chlorella vulgaris, Neochloris oleoabundans and Tetraselmis suecica) was studied in a lab scale bead mill at different bead sizes (0.3–1 mm). Cell disintegration, proteins and carbohydrates released into the water phase followed a first order

  6. Solvent density inhomogeneities and solvation free energies in supercritical diatomic fluids: a density functional approach.

    Science.gov (United States)

    Husowitz, B; Talanquer, V

    2007-02-07

    Density functional theory is used to explore the solvation properties of a spherical solute immersed in a supercritical diatomic fluid. The solute is modeled as a hard core Yukawa particle surrounded by a diatomic Lennard-Jones fluid represented by two fused tangent spheres using an interaction site approximation. The authors' approach is particularly suitable for thoroughly exploring the effect of different interaction parameters, such as solute-solvent interaction strength and range, solvent-solvent long-range interactions, and particle size, on the local solvent structure and the solvation free energy under supercritical conditions. Their results indicate that the behavior of the local coordination number in homonuclear diatomic fluids follows trends similar to those reported in previous studies for monatomic fluids. The local density augmentation is particularly sensitive to changes in solute size and is affected to a lesser degree by variations in the solute-solvent interaction strength and range. The associated solvation free energies exhibit a nonmonotonous behavior as a function of density for systems with weak solute-solvent interactions. The authors' results suggest that solute-solvent interaction anisotropies have a major influence on the nature and extent of local solvent density inhomogeneities and on the value of the solvation free energies in supercritical solutions of heteronuclear molecules.

  7. Energy Cost of Avoiding Pressure Oscillations in a Discrete Fluid Power Force System

    DEFF Research Database (Denmark)

    Hansen, Anders Hedegaard; Pedersen, Henrik Clemmensen

    2015-01-01

    In secondary valve controlled discrete fluid power force systems the valve opening trajectory greatly influences the pressure dynamics in the actuator chambers. For discrete fluid power systems featuring hoses of significant length pressure oscillations due to fast valve switching is well......-known. This paper builds upon theoretical findings on how shaping of the valve opening may reduce the cylinder pressure oscillations. The current paper extents the work by implementing the valve opening characteristics reducing the pressure oscillations on a full scale power take-off test-bench for wave energy...

  8. Boundary layer flow of Maxwell fluid in rotating frame with binary chemical reaction and activation energy

    Directory of Open Access Journals (Sweden)

    Z. Shafique

    Full Text Available Here we study the heat/mass transfer effects on revolving flow of Maxwell fluid due to unidirectional stretching surface. Mass transfer process is modeled in terms of binary chemical reaction and activation energy. Modified Arrhenius function for activation energy is invoked. Traditional boundary layer approximations are utilized to simplify the governing equations. Using similarity method, self-similar form of boundary layer equations are derived which are solved numerically. The solutions depend on dimensionless numbers such as the rotation parameter λ, the Deborah number β, the Prandtl number Pr, the Schmidt number Sc, activation energy E, fitted rate constant n and temperature difference parameter δ. We found that the solute concentration in binary mixture is proportional to both rotation parameter λ and activation energy E. The reaction rate σ and fitted rate n both provide reduction in the solute concentration. Thermal boundary layer becomes thicker and heat transfer rate diminishes when fluid is subjected to a larger rotation rate. Keywords: Maxwell fluid, Activation energy, Chemical reaction, Numerical solution, Rotating frame, Stretching sheet

  9. Electrophilic acid gas-reactive fluid, proppant, and process for enhanced fracturing and recovery of energy producing materials

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, Carlos A.; Heldebrant, David J.; Bonneville, Alain; Jung, Hun Bok; Carroll, Kenneth C.

    2018-01-23

    An electrophilic acid gas-reactive fracturing fluid, proppant, and process are detailed. The fluid expands in volume to provide rapid and controlled increases in pressure that enhances fracturing in subterranean bedrock for recovery of energy-producing materials. The proppant stabilizes fracture openings in the bedrock to enhance recovery of energy-producing materials.

  10. Process for Transition of Uranium Mill Tailings Radiation Control Act Title II Disposal Sites to the U.S. Department of Energy Office of Legacy Management for Long-Term Surveillance and Maintenance

    Energy Technology Data Exchange (ETDEWEB)

    None

    2012-03-01

    This document presents guidance for implementing the process that the U.S. Department of Energy (DOE) Office of Legacy Management (LM) will use for assuming perpetual responsibility for a closed uranium mill tailings site. The transition process specifically addresses sites regulated under Title II of the Uranium Mill Tailings Radiation Control Act (UMTRCA) but is applicable in principle to the transition of sites under other regulatory structures, such as the Formerly Utilized Sites Remedial Action Program.

  11. Statistically generated events and the fluid-dynamical expectation in high energy nucleon collisions

    International Nuclear Information System (INIS)

    Csernai, L.P.; Randrup, J.; Fai, G.

    1984-01-01

    Experimental developments point in the direction of measuring exclusive quantities in high-energy nuclear collisions. On the theory side a computer simulation model has been put forward recently to generate complete (exclusive) events statistically. In the present work this model together with fluid-dynamical results is used to see how the formation of composite fragments, the finiteness of the multiplicity, and the statistical fluctuations in the final states affect the event analysis. From a series of detailed three-dimensional fluid-dynamical calculations certain gross features are extracted that are used to give an approximate characterization of the final state of the fluid dynamical state of the collision in terms of a few subsystems (sources), a participant source and up to two spectator sources

  12. Phase-resolved fluid dynamic forces of a flapping foil energy harvester based on PIV measurements

    Science.gov (United States)

    Liburdy, James

    2017-11-01

    Two-dimensional particle image velocimetry measurements are performed in a wind tunnel to evaluate the spatial and temporal fluid dynamic forces acting on a flapping foil operating in the energy harvesting regime. Experiments are conducted at reduced frequencies (k = fc/U) of 0.05 - 0.2, pitching angle of, and heaving amplitude of A / c = 0.6. The phase-averaged pressure field is obtained by integrating the pressure Poisson equation. Fluid dynamic forces are then obtained through the integral momentum equation. Results are compared with a simple force model based on the concept of flow impulse. These results help to show the detailed force distributions, their transient nature and aide in understanding the impact of the fluid flow structures that contribute to the power production.

  13. Computer simulation of energy use, greenhouse gas emissions, and process economics of the fluid milk process.

    Science.gov (United States)

    Tomasula, P M; Yee, W C F; McAloon, A J; Nutter, D W; Bonnaillie, L M

    2013-05-01

    Energy-savings measures have been implemented in fluid milk plants to lower energy costs and the energy-related carbon dioxide (CO2) emissions. Although these measures have resulted in reductions in steam, electricity, compressed air, and refrigeration use of up to 30%, a benchmarking framework is necessary to examine the implementation of process-specific measures that would lower energy use, costs, and CO2 emissions even further. In this study, using information provided by the dairy industry and equipment vendors, a customizable model of the fluid milk process was developed for use in process design software to benchmark the electrical and fuel energy consumption and CO2 emissions of current processes. It may also be used to test the feasibility of new processing concepts to lower energy and CO2 emissions with calculation of new capital and operating costs. The accuracy of the model in predicting total energy usage of the entire fluid milk process and the pasteurization step was validated using available literature and industry energy data. Computer simulation of small (40.0 million L/yr), medium (113.6 million L/yr), and large (227.1 million L/yr) processing plants predicted the carbon footprint of milk, defined as grams of CO2 equivalents (CO2e) per kilogram of packaged milk, to within 5% of the value of 96 g of CO 2e/kg of packaged milk obtained in an industry-conducted life cycle assessment and also showed, in agreement with the same study, that plant size had no effect on the carbon footprint of milk but that larger plants were more cost effective in producing milk. Analysis of the pasteurization step showed that increasing the percentage regeneration of the pasteurizer from 90 to 96% would lower its thermal energy use by almost 60% and that implementation of partial homogenization would lower electrical energy use and CO2e emissions of homogenization by 82 and 5.4%, respectively. It was also demonstrated that implementation of steps to lower non

  14. Workshop on induced Seismicity due to fluid injection/production from Energy-Related Applications

    Energy Technology Data Exchange (ETDEWEB)

    Majer, E.L.; Asanuma, Hiroshi; Rueter, Horst; Stump, Brian; Segall, Paul; Zoback, Mark; Nelson, Jim; Frohlich, Cliff; Rutledge, Jim; Gritto, Roland; Baria, Roy; Hickman, Steve; McGarr, Art; Ellsworth, Bill; Lockner, Dave; Oppenheimer, David; Henning, Peter; Rosca, Anca; Hornby, Brian; Wang, Herb; Beeler, Nick; Ghassemi, Ahmad; Walters, Mark; Robertson-Tait, Ann; Dracos, Peter; Fehler, Mike; Abou-Sayed, Ahmed; Ake, Jon; Vorobiev, Oleg; Julian, Bruce

    2011-04-01

    Geothermal energy, carbon sequestration, and enhanced oil and gas recovery have a clear role in U.S. energy policy, both in securing cost-effective energy and reducing atmospheric CO{sub 2} accumulations. Recent publicity surrounding induced seismicity at several geothermal and oil and gas sites points out the need to develop improved standards and practices to avoid issues that may unduly inhibit or stop the above technologies from fulfilling their full potential. It is critical that policy makers and the general community be assured that EGS, CO{sub 2} sequestration, enhanced oil/gas recovery, and other technologies relying on fluid injections, will be designed to reduce induced seismicity to an acceptable level, and be developed in a safe and cost-effective manner. Induced seismicity is not new - it has occurred as part of many different energy and industrial applications (reservoir impoundment, mining, oil recovery, construction, waste disposal, conventional geothermal). With proper study/research and engineering controls, induced seismicity should eventually allow safe and cost-effective implementation of any of these technologies. In addition, microseismicity is now being used as a remote sensing tool for understanding and measuring the success of injecting fluid into the subsurface in a variety of applications, including the enhancement of formation permeability through fracture creation/reactivation, tracking fluid migration and storage, and physics associated with stress redistribution. This potential problem was envisaged in 2004 following observed seismicity at several EGS sites, a study was implemented by DOE to produce a white paper and a protocol (Majer et al 2008) to help potential investors. Recently, however, there have been a significant number of adverse comments by the press regarding induced seismicity which could adversely affect the development of the energy sector in the USA. Therefore, in order to identify critical technology and research

  15. Report of workshop on vibration related to fluid in atomic energy field. 4

    International Nuclear Information System (INIS)

    1993-01-01

    This is the fourth workshop on the vibration related to fluid in atomic energy field of Yayoi research group. This time, two topics were taken up. One is edgetone phenomena and the liquid surface vibration phenomena due to flow. Another is the introduction of the experience in light water reactors. The workshop was held on August 30 and 31, 1993 at Nuclear Engineering Research Laboratory, University of Tokyo. At the workshop, lectures were given on the mechanism of occurrence of edgetone, the theoretical analysis of edgetone and edgenoise, the self-excited vibration of free liquid surface due to vertical plane jet and vertical cylindrical jet, the research on flow instability phenomena in parallel loop system, the irregular vibration behavior of U-shaped tubes excited by flow, the research on the vibration of cyclindrical weir due to fluid discharge, the examples of the vibration related to fluid in LWRs, the estimation of fatigue phenomena in bearing rings, the vibration of rotary vanes and verifying test, the analysis of flow in isolated phase bus plate vane and the measurement of velocity distribution, flow in piping and the behavior of valve vibration, the condition for the occurrence of flow vibration in the main steam separation valve of BWR, the vibration of piping due to orifice, the analysis of flow in two-dimensional vibrating cascade, and the subjects of fluid vibration assessment in atomic energy. (K.I.)

  16. An energy-stable finite-difference scheme for the binary fluid-surfactant system

    Science.gov (United States)

    Gu, Shuting; Zhang, Hui; Zhang, Zhengru

    2014-08-01

    We present an unconditionally energy stable finite-difference scheme for the binary fluid-surfactant system. The proposed method is based on the convex splitting of the energy functional with two variables. Here are two distinct features: (i) the convex splitting energy method is applied to energy functional with two variables, and (ii) the stability issue is related to the decay of the corresponding energy. The full discrete scheme leads to a decoupled system including a linear sub-system and a nonlinear sub-system. Algebraic multigrid and Newton-multigrid methods are adopted to solve the linear and nonlinear systems, respectively. Numerical experiments are shown to verify the stability of such a scheme.

  17. Relationship between Energy Expenditure Related Factors and Oxidative Stress in Follicular Fluid

    OpenAIRE

    Kazemi, Ashraf; Ramezanzadeh, Fatemeh; Nasr Esfahani, Mohammad Hosein; Saboor-Yaraghi, Ali Akbar; Nejat, Saharnaz Nejat; Rahimi-Foroshani, Abbas

    2014-01-01

    Background This study evaluated the impact of body mass index (BMI), total calorie intake and physical activity (PA) as energy expenditure related factors on oxidative stress (OS) in follicular fluid (FF). Materials and Methods This prospective study conducted on 219 infertile women. We evaluated patients’ BMI, total calorie intake and PA in their assisted reproduction treatment cycles. Malondialdehyde (MDA) and total antioxidant capacity (TAC) in pooled FF at oocyte retrieval were additional...

  18. a Matlab Toolbox for Basin Scale Fluid Flow Modeling Applied to Hydrology and Geothermal Energy

    Science.gov (United States)

    Alcanie, M.; Lupi, M.; Carrier, A.

    2017-12-01

    Recent boosts in the development of geothermal energy were fostered by the latest oil crises and by the need of reducing CO2 emissions generated by the combustion of fossil fuels. Various numerical codes (e.g. FEHM, CSMP++, HYDROTHERM, TOUGH) have thus been implemented for the simulation and quantification of fluid flow in the upper crust. One possible limitation of such codes is the limited accessibility and the complex structure of the simulators. For this reason, we began to develop a Hydrothermal Fluid Flow Matlab library as part of MRST (Matlab Reservoir Simulation Toolbox). MRST is designed for the simulation of oil and gas problems including carbon capture storage. However, a geothermal module is still missing. We selected the Geneva Basin as a natural laboratory because of the large amount of data available in the region. The Geneva Basin has been intensely investigated in the past with exploration wells, active seismic and gravity surveys. In addition, the energy strategy of Switzerland promotes the development of geothermal energy that lead to recent geophysical prospections. Previous and ongoing projects have shown the geothermal potential of the Geneva Basin but a consistent fluid flow model assessing the deep circulation in the region is yet to be defined. The first step of the study was to create the basin-scale static model. We integrated available active seismic, gravity inversions and borehole data to describe the principal geologic and tectonic features of the Geneva Basin. Petrophysical parameters were obtained from available and widespread well logs. This required adapting MRST to standard text format file imports and outline a new methodology for quick static model creation in an open source environment. We implemented several basin-scale fluid flow models to test the effects of petrophysical properties on the circulation dynamics of deep fluids in the Geneva Basin. Preliminary results allow the identification of preferential fluid flow

  19. Dark energy with a gradient coupling to the dark matter fluid: cosmological dynamics and structure formation

    Science.gov (United States)

    Dutta, Jibitesh; Khyllep, Wompherdeiki; Tamanini, Nicola

    2018-01-01

    We consider scalar field models of dark energy interacting with dark matter through a coupling proportional to the contraction of the four-derivative of the scalar field with the four-velocity of the dark matter fluid. The coupling is realized at the Lagrangian level employing the formalism of Scalar-Fluid theories, which use a consistent Lagrangian approach for relativistic fluid to describe dark matter. This framework produces fully covariant field equations, from which we can derive unequivocal cosmological equations at both background and linear perturbations levels. The background evolution is analyzed in detail applying dynamical systems techniques, which allow us to find the complete asymptotic behavior of the universe given any set of model parameters and initial conditions. Furthermore we study linear cosmological perturbations investigating the growth of cosmic structures within the quasi-static approximation. We find that these interacting dark energy models give rise to interesting phenomenological dynamics, including late-time transitions from dark matter to dark energy domination, matter and accelerated scaling solutions and dynamical crossing of the phantom barrier. Moreover we obtain possible deviations from standard ΛCDM behavior at the linear perturbations level, which have an impact on the dynamics of structure formation and might provide characteristic observational signatures.

  20. Beyond the perfect fluid hypothesis for the dark energy equation of state

    International Nuclear Information System (INIS)

    Cardone, V.F.; Troisi, A.; Tortora, C.; Capozziello, S.

    2006-01-01

    Abandoning the perfect fluid hypothesis, we investigate here the possibility that the dark energy equation of state (EoS) w is a nonlinear function of the energy density ρ. To this aim, we consider four different EoS describing classical fluids near thermodynamical critical points and discuss the main features of cosmological models made out of dust matter and a dark energy term with the given EoS. Each model is tested against the data on the dimensionless coordinate distance to Type Ia Supernovae and radio galaxies, the shift and the acoustic peak parameters and the positions of the first three peaks in the anisotropy spectrum of the comic microwave background radiation. We propose a possible interpretation of each model in the framework of scalar field quintessence determining the shape of the self-interaction potential V(φ) that gives rise to each one of the considered thermodynamical EoS. As a general result, we demonstrate that replacing the perfect fluid EoS with more general expressions gives both the possibility of successfully solving the problem of cosmic acceleration escaping the resort to phantom models

  1. Synthesis of stoichiometric Ca{sub 2}Fe{sub 2}O{sub 5} nanoparticles by high-energy ball milling and thermal annealing

    Energy Technology Data Exchange (ETDEWEB)

    Amorim, B.F.; Morales, M.A.; Bohn, F.; Carriço, A.S. [Departamento de Física Teórica e Experimental, Universidade Federal do Rio Grande do Norte, 59078-900 Natal, RN (Brazil); Medeiros, S.N. de, E-mail: sndemedeiros@gmail.com [Departamento de Física Teórica e Experimental, Universidade Federal do Rio Grande do Norte, 59078-900 Natal, RN (Brazil); Dantas, A.L. [Departamento de Física, Universidade do Estado do Rio Grande do Norte, 59610-210 Mossoró, RN (Brazil)

    2016-05-01

    We report the synthesis of Ca{sub 2}Fe{sub 2}O{sub 5} nanoparticles by high-energy ball milling and thermal annealing from α-Fe{sub 2}O{sub 3} and CaCO{sub 3}. Magnetization measurements, Mössbauer and X-ray spectra reveal that annealing at high temperatures leads to better quality samples. Our results indicate nanoparticles produced by 10 h high-energy ball milling and thermal annealing for 2 h at 1100 °C achieve improved stoichiometry and the full weak ferromagnetic signal of Ca{sub 2}Fe{sub 2}O{sub 5}. Samples annealed at lower temperatures show departure from stoichiometry, with a higher occupancy of Fe{sup 3+} in octahedral sites, and a reduced magnetization. Thermal relaxation for temperatures in the 700–1100 °C range is well represented by a Néel model, assuming a random orientation of the weak ferromagnetic moment of the Ca{sub 2}Fe{sub 2}O{sub 5} nanoparticles.

  2. From fluid milk to milk powder: Energy use and energy efficiency in the European dairy industry

    International Nuclear Information System (INIS)

    Ramirez, C.A.; Patel, M.; Blok, K.

    2006-01-01

    In this paper, we conduct a cross-country analysis of energy consumption and energy efficiency for the dairy industry in four European countries. Changes in energy efficiency were monitored in two different ways. One way is to look at the energy use by tonne of milk processed by dairies (EEI p1 ). Another way is by comparing the actual energy use with the energy that would have been used if no changes in energy efficiency would have taken place (EEI p2 ). A characteristic of EEI p2 is that it corrects for differences in product mix among countries and in time. We found that changes in production mix are important in three of the four countries studied and that EEI p2 should be preferred when comparing levels of energy efficiency among countries or when there are significant changes in product mix. Once changes in product mix have been taken into account, our results show that France, Germany, the Netherlands and the United Kingdom have reduced their values in EEI p2 , respectively by -0.4%, -2.1%, -1.2% and -3.8% per annum. The results also show that the British, German and Dutch dairy industries have converged towards similar (lower) values in their energy efficiency indicators and that the French dairy industry would save 30% if were to converge to similar values of EEI p as the ones obtained for Germany or the United Kingdom

  3. Proceedings of the fourteenth symposium on energy engineering sciences: Mechanical sciences; Solids and fluids

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-10-01

    The Engineering Research Program is charged with the identification, initiation, and management of fundamental research on broad, generic topics addressing energy-related engineering problems. Its stated goals are: (1) to improve and extend the body of knowledge underlying current engineering practice so as to create new options for enhancing energy savings and production, for prolonging useful life of energy-related structures and equipment and for developing advanced manufacturing technologies and materials processing with emphasis on reducing costs with improved industrial production and performance quality; (2) to expand the store of fundamental concepts for solving anticipated and unforeseen engineering problems in the energy technologies. The 26 papers in this proceedings are arranged in the following topical sections: superconductors (4 papers); materials (7); controls (4); fluid mechanics (7); and thin films (4). Papers have been processed separately for inclusion on the data base.

  4. Dark energy interacting with dark matter and a third fluid: Possible EoS for this component

    Energy Technology Data Exchange (ETDEWEB)

    Cruz, Norman, E-mail: ncruz@lauca.usach.c [Departamento de Fisica, Facultad de Ciencia, Universidad de Santiago, Casilla 307, Santiago (Chile); Lepe, Samuel, E-mail: slepe@ucv.c [Instituto de Fisica, Facultad de Ciencias, Pontificia Universidad Catolica de Valparaiso, Casilla 4059, Valparaiso (Chile); Pena, Francisco, E-mail: fcampos@ufro.c [Departamento de Ciencias Fisicas, Facultad de Ingenieria, Ciencias y Administracion, Universidad de La Frontera, Avda. Francisco Salazar 01145, Casilla 54-D, Temuco (Chile)

    2011-05-09

    A cosmological model of dark energy interacting with dark matter and another general component of the universe is considered. The equations for the coincidence parameters r and s, which represent the ratios between dark energy and dark matter and the other cosmic fluid respectively, are analyzed in terms of the stability of stationary solutions. The obtained general results allow to shed some light on the equations of state of the three interacting fluids, due to the constraints imposed by the stability of the solutions. We found that for an interaction proportional to the sum of the dark energy density and the third fluid density, the hypothetical fluid must have positive pressure, which leads naturally to a cosmological scenario with radiation, unparticle or even some form of warm dark matter as the third interacting fluid.

  5. Dark energy interacting with dark matter and a third fluid: Possible EoS for this component

    International Nuclear Information System (INIS)

    Cruz, Norman; Lepe, Samuel; Pena, Francisco

    2011-01-01

    A cosmological model of dark energy interacting with dark matter and another general component of the universe is considered. The equations for the coincidence parameters r and s, which represent the ratios between dark energy and dark matter and the other cosmic fluid respectively, are analyzed in terms of the stability of stationary solutions. The obtained general results allow to shed some light on the equations of state of the three interacting fluids, due to the constraints imposed by the stability of the solutions. We found that for an interaction proportional to the sum of the dark energy density and the third fluid density, the hypothetical fluid must have positive pressure, which leads naturally to a cosmological scenario with radiation, unparticle or even some form of warm dark matter as the third interacting fluid.

  6. Cerebral energy metabolism following fluid-percussion brain injury in cats.

    Science.gov (United States)

    Unterberg, A W; Andersen, B J; Clarke, G D; Marmarou, A

    1988-04-01

    Clinical and experimental evidence suggests that head injury can cause alterations of cerebral energy metabolism. However, the etiology of this metabolic perturbation is not known. The objective of this study was to determine the effect of fluid-percussion trauma on cerebral energy metabolism. Seven ventilated, chloralose-anesthetized cats were subjected to a 3.2-atm fluid-percussion brain injury. Before and for 8 hours after trauma, continuous phosphorus-3 1 magnetic resonance spectrography was obtained to noninvasively monitor tissue pH, phosphocreatine (PCr), and inorganic phosphate (Pi) levels. Measurement of cerebral blood flow (CBF) by the radioactive microsphere technique and calculation of oxygen and glucose consumption (CMRO2 and CMRG1) were also performed before trauma as well as 30 minutes and 1, 2, 4, and 8 hours after trauma. The data showed a moderate decrease in tissue pH from 7.04 to 6.89 at 30 minutes following trauma with return to control levels by 3 hours posttrauma. During the 8-hour observation period, CBF, CMRO2, and CMRG1 remained at control levels. Tissue PCr and Pi levels were also unchanged. Fluid-percussion trauma at the 3.2-atm level in ventilated cats causes a moderate and transient decrease in tissue pH that returns to control levels after trauma. No other metabolic changes are seen later than 30 minutes posttrauma. This indicates that a mild metabolic disturbance occurs after trauma in the ventilated animal and quickly returns to normal.

  7. Equiparatition of energy for turbulent astrophysical fluids: Accounting for the unseen energy in molecular clouds

    Science.gov (United States)

    Zweibel, Ellen G.; Mckee, Christopher F.

    1995-01-01

    Molecular clouds are observed to be partially supported by turbulent pressure. The kinetic energy of the turbulence is directly measurable, but the potential energy, which consists of magnetic, thermal, and gravitational potential energy, is largly unseen. We have extended previous results on equipartition between kinetic and potential energy to show that it is likely to be a very good approximation in molecular clouds. We have used two separate approaches to demonstrate this result: For small-amplitude perturbations of a static equilibrium, we have used the energy principle analysis of Bernstein et al. (1958); this derivation applies to perturbations of arbitary wavelength. To treat perturbations of a nonstatic equilibrium, we have used the Lagrangian analysis of Dewar (1970); this analysis applies only to short-wavelength perturbations. Both analysis assume conservation of energy. Wave damping has only a small effect on equipartition if the wave frequency is small compared to the neutral-ion collision frequency; for the particular case we considered, radiative losses have no effect on equipartition. These results are then incorporated in a simple way into analyses of cloud equilibrium and global stability. We discuss the effect of Alfvenic turbulence on the Jeans mass and show that it has little effect on the magnetic critical mass.

  8. Extrema principles of entrophy production and energy dissipation in fluid mechanics

    Science.gov (United States)

    Horne, W. Clifton; Karamcheti, Krishnamurty

    1988-01-01

    A survey is presented of several extrema principles of energy dissipation as applied to problems in fluid mechanics. An exact equation is derived for the dissipation function of a homogeneous, isotropic, Newtonian fluid, with terms associated with irreversible compression or expansion, wave radiation, and the square of the vorticity. By using entropy extrema principles, simple flows such as the incompressible channel flow and the cylindrical vortex are identified as minimal dissipative distributions. The principal notions of stability of parallel shear flows appears to be associated with a maximum dissipation condition. These different conditions are consistent with Prigogine's classification of thermodynamic states into categories of equilibrium, linear nonequilibrium, and nonlinear nonequilibrium thermodynamics; vortices and acoustic waves appear as examples of dissipative structures. The measurements of a typical periodic shear flow, the rectangular wall jet, show that direct measurements of the dissipative terms are possible.

  9. Energy saving during bulb storage applying modeling with computational fluid dynamics (CFD)

    Energy Technology Data Exchange (ETDEWEB)

    Sapounas, A.A.; Campen, J.B.; Wildschut, J.; Bot, G.P. [Wageningen UR Greenhouse Horticutlure and Applied Plant Research, Wageningen (Netherlands)

    2010-07-01

    Tulip bulbs are stored in ventilated containers to avoid high ethylene concentration between the bulbs. A commercial computational fluid dynamics (CFD) code was used in this study to examine the distribution of air flow between the containers and the potential energy saving by applying simple solutions concerning the design of the air inlet area and the adjustment of the ventilation rate. The variation in container ventilation was calculated to be between 60 and 180 per cent, with 100 per cent being the average flow through the containers. Various improvement measures were examined. The study showed that 7 per cent energy can be saved by smoothing the sharp corners of the entrance channels of the ventilation wall. The most effective and simple improvement was to cover the open top containers. In this case, the variation was between 80 and 120 per cent. The energy saving was about 38 per cent by adjusting the overall ventilation to the container with the minimal acceptable air flow.

  10. Temporal changes in fluid chemistry and energy profiles in the vulcano island hydrothermal system.

    Science.gov (United States)

    Rogers, Karyn L; Amend, Jan P; Gurrieri, Sergio

    2007-12-01

    In June 2003, the geochemical composition of geothermal fluids was determined at 9 sites in the Vulcano hydrothermal system, including sediment seeps, geothermal wells, and submarine vents. Compositional data were combined with standard state reaction properties to determine the overall Gibbs free energy (DeltaG(r) ) for 120 potential lithotrophic and heterotrophic reactions. Lithotrophic reactions in the H-O-N-S-C-Fe system were considered, and exergonic reactions yielded up to 120 kJ per mole of electrons transferred. The potential for heterotrophy was characterized by energy yields from the complete oxidation of 6 carboxylic acids- formic, acetic, propanoic, lactic, pyruvic, and succinic-with the following redox pairs: O(2)/H(2)O, SO(4) (2)/H(2)S, NO(3) ()/NH(4) (+), S(0)/H(2)S, and Fe(3)O(4)/Fe(2+). Heterotrophic reactions yielded 6-111 kJ/mol e(). Energy yields from both lithotrophic and heterotrophic reactions were highly dependent on the terminal electron acceptor (TEA); reactions with O(2) yielded the most energy, followed by those with NO(3) (), Fe(III), SO(4) (2), and S(0). When only reactions with complete TEA reduction were included, the exergonic lithotrophic reactions followed a similar electron tower. Spatial variability in DeltaG(r) was significant for iron redox reactions, owing largely to the wide range in Fe(2+) and H(+) concentrations. Energy yields were compared to those obtained for samples collected in June 2001. The temporal variations in geochemical composition and energy yields observed in the Vulcano hydrothermal system between 2001 and 2003 were moderate. The largest differences in DeltaG(r) over the 2 years were from iron redox reactions, due to temporal changes in the Fe(2+) and H(+) concentrations. The observed variations in fluid composition across the Vulcano hydrothermal system have the potential to influence not only microbial diversity but also the metabolic strategies of the resident microbial communities.

  11. Evaluation of the Fluid Model Approach for the Sizing of Energy Storage in Wave-Wind Energy Systems

    Directory of Open Access Journals (Sweden)

    José A. Domínguez-Navarro

    2016-03-01

    Full Text Available The application of energy storage in offshore renewable generation systems allows managing the intrinsic uncertainty of the resources and improving the utilization factor of the electrical network. Optimal storage design algorithms generally have to evaluate the behavior of the whole system thousands times before converging to the optimal solution and the reliability of the results obviously depends on the quality of input data. On the other hand, the utilization of simplified storage models in the design stage can reduce the simulation time drastically, while still providing useful information. The goal of this paper is to evaluate the applicability of a methodology for sizing the energy storage system in a hybrid wind and wave farm, which is based on fluid models. The description and performance of this modeling approach will be introduced and compared to standard design procedures based on extensive simulations. Advantages and limitations of each approach will be underlined and the impact of input data quality will be discussed.

  12. Obtention of the TiFe compound by high-energy milling of Ti+Fe and TiH{sub 2}+Fe powder mixtures; Obtencao do composto TiFe a partir da moagem de alta energia de misturas Ti+Fe e TiH{sub 2}+Fe

    Energy Technology Data Exchange (ETDEWEB)

    Falcao, R.B.; Dammann, E.D.C.C.; Rocha, C.J.; Leal Neto, R.M., E-mail: railson.falcao@usp.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Ciencias e Tecnologia de Materiais. Lab. de Intermetalicos

    2010-07-01

    In this work TiFe compound was obtained by two process routes involving high-energy ball milling: mechanical alloying from Ti and Fe powders (route 1) and mechanical milling from TiH{sub 2} and Fe powders, both followed by an annealing heat treatment. Shaker and planetary ball mills were utilized for times varying from 1-25 hours. Milled and annealed powders were characterized by SEM and X-ray diffraction analyses. TiFe compound was formed in both routes. A strong powder adherence in the milling vial and balls occurred with route 1 in both mills. Powder adherence was significantly reduced by using TiH{sub 2} (route 2) mainly in the planetary mill, in spite of TiFe formation has only occurred after the annealing treatment. (author)

  13. Dark fluid: A complex scalar field to unify dark energy and dark matter

    International Nuclear Information System (INIS)

    Arbey, Alexandre

    2006-01-01

    In this article, we examine a model which proposes a common explanation for the presence of additional attractive gravitational effects - generally considered to be due to dark matter - in galaxies and in clusters, and for the presence of a repulsive effect at cosmological scales - generally taken as an indication of the presence of dark energy. We therefore consider the behavior of a so-called dark fluid based on a complex scalar field with a conserved U(1)-charge and associated to a specific potential, and show that it can at the same time account for dark matter in galaxies and in clusters, and agree with the cosmological observations and constraints on dark energy and dark matter

  14. Energy transfer in compressible magnetohydrodynamic turbulence for isothermal self-gravitating fluids

    Science.gov (United States)

    Banerjee, Supratik; Kritsuk, Alexei G.

    2018-02-01

    Three-dimensional, compressible, magnetohydrodynamic turbulence of an isothermal, self-gravitating fluid is analyzed using two-point statistics in the asymptotic limit of large Reynolds numbers (both kinetic and magnetic). Following an alternative formulation proposed by Banerjee and Galtier [Phys. Rev. E 93, 033120 (2016), 10.1103/PhysRevE.93.033120; J. Phys. A: Math. Theor. 50, 015501 (2017), 10.1088/1751-8113/50/1/015501], an exact relation has been derived for the total energy transfer. This approach results in a simpler relation expressed entirely in terms of mixed second-order structure functions. The kinetic, thermodynamic, magnetic, and gravitational contributions to the energy transfer rate can be easily separated in the present form. By construction, the new formalism includes such additional effects as global rotation, the Hall term in the induction equation, etc. The analysis shows that solid-body rotation cannot alter the energy flux rate of compressible turbulence. However, the contribution of a uniform background magnetic field to the flux is shown to be nontrivial unlike in the incompressible case. Finally, the compressible, turbulent energy flux rate does not vanish completely due to simple alignments, which leads to a zero turbulent energy flux rate in the incompressible case.

  15. Wormholes supported by phantom energy from Shan-Chen cosmological fluids

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Deng [Nankai University, Theoretical Physics Division, Chern Institute of Mathematics, Tianjin (China); Meng, Xin-He [Nankai University, Department of Physics, Tianjin (China); Institute of Theoretical Physics, CAS, State key Lab of Theoretical Physics, Beijing (China)

    2016-03-15

    In the present paper, the exact solutions of spherically symmetrical Einstein field equations describing wormholes supported by phantom energy that violates the null energy condition from Shan-Chen background fluid are obtained. We have considered the important case of the model parameter ψ ∼ 1, which corresponds to the ''saturation effect'', and this regime corresponds to an effective form of ''asymptotic freedom'' for the fluids, but occurring at cosmological rather than subnuclear scales. Then we investigate the allowed range for the values of the model parameters g and ω when the spacetime metrics describe wormholes and discuss the possible singularities of the solutions, finding that the obtained spacetimes are geodesically complete. Furthermore, we construct two traversable wormholes through matching our obtained interior solutions to the exterior Schwarzschild solutions and analyze the traversabilities of the wormholes. Finally, we consider the case of anisotropic pressure and discover that the transverse pressure also crosses the phantom divide -1 with the growth of the wormhole dimension, and it tends to be the same as the radial pressure with the growth of the wormhole radius. (orig.)

  16. Energy Cascade from Internal Modes in Non-uniformly Stratified Fluid through Excitation of Superharmonic Disturbances

    Science.gov (United States)

    Sutherland, B. R.

    2016-02-01

    It is well established that two-dimensional internal plane waves and modes in uniformly stratified fluid efficiently transfer energy to smaller scale waves and ultimately turbulent mixing through parametric subharmonic instability (PSI). The numerical simulations of MacKinnon & Winters (GRL 2005) predicted PSI should act efficiently to disrupt the internal tide. However, while in situ observations showed the presence of PSI, it was not found to be appreciable. One reason for the discrepancy between simulations and observations is that the former examined an internal mode in uniformly stratified fluid whereas, in reality, the internal tide exists in non-uniform stratification and is manifest as sinusoidal oscillations of the thermocline. Through theory supported by numerical simulations, it is shown that internal modes in non-uniform stratification immediately excite superharmonics, not subharmonic disturbances. These have double the horizontal wavenumber and double the frequency of the parent mode and hence move with the same horizontal phase speed of the parent mode. As the disturbances grow in amplitude, however, they interact with the parent mode generating small-scale vertically propagating internal waves within the strongly stratified layer. The occurrence of PSI over very long times can occur, as in the simulations of Hazewinkel and Winters (JPO 2011). However, a comprehensive understanding of the energy cascade from the internal tide to small scales must consider the evolution of excited superharmonic disturbances.

  17. Electrokinetic energy conversion efficiency of viscoelastic fluids in a polyelectrolyte-grafted nanochannel.

    Science.gov (United States)

    Jian, Yongjun; Li, Fengqin; Liu, Yongbo; Chang, Long; Liu, Quansheng; Yang, Liangui

    2017-08-01

    In order to conduct extensive investigation of energy harvesting capabilities of nanofluidic devices, we provide analytical solutions for streaming potential and electrokinetic energy conversion (EKEC) efficiency through taking the combined consequences of soft nanochannel, a rigid nanochannel whose surface is covered by charged polyelectrolyte layer, and viscoelastic rheology into account. The viscoelasticity of the fluid is considered by employing the Maxwell constitutive model when the forcing frequency of an oscillatory driving pressure flow matches with the inverse of the relaxation time scale of a typical viscoelastic fluid. We compare the streaming potential and EKEC efficiency with those of a rigid nanochannel, having zeta potential equal to the electrostatic potential at the solid-polyelectrolyte interface of the soft nanochannels. Within the present selected parameter ranges, it is shown that the different peaks of maximal streaming potential and EKEC efficiency for the rigid nanochannel are larger than those for the soft nanochannel when forcing frequencies of the driving pressure gradient are close to resonating frequencies. However, more enhanced streaming potential and EKEC efficiency for a soft nanochannel can be found in most of the regions away from these resonant frequencies. Moreover, the influence of several dimensionless parameters on EKEC efficiency is discussed in detail. Finally, within the given parametric regions, the maximum efficiency at some resonant frequency obtained in present analysis is about 25%. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Cost-benefit analysis of wind energy. A case study of Kayathar wind mills in Tamil Nadu

    Energy Technology Data Exchange (ETDEWEB)

    Varadarajan, D.B. [Madurai Kamaraj Univ., Madurai (India). Dept. of Environmental Economics

    1995-12-31

    In recent years we have been encountering what is termed as Energy Crisis. Energy crisis is not only a threat to any economy but also posses a challenge in correcting the deficiency. India which is going in for massive industrialization is a population giant and has to reckon with the very relevant issue of energy crisis. In this regard the Indian Government has laid a great deal of emphasis on the development and harnessing of alternative sources of energy. Among the various types of renewable energy sources wind energy is present by the only proven alternative in the energy structure. Along with the evolution of man form primitive stage to the present civilisation, the wind energy has also moved with time from its ancient period to the present stage of sophistication which can be adopted to various needs like water pumping and power generation. (author)

  19. Cost-benefit analysis of wind energy. A case study of Kayathar wind mills in Tamil Nadu

    International Nuclear Information System (INIS)

    Varadarajan, D.B.

    1995-01-01

    In recent years we have been encountering what is termed as Energy Crisis. Energy crisis is not only a threat to any economy but also posses a challenge in correcting the deficiency. India which is going in for massive industrialization is a population giant and has to reckon with the very relevant issue of energy crisis. In this regard the Indian Government has laid a great deal of emphasis on the development and harnessing of alternative sources of energy. Among the various types of renewable energy sources wind energy is present by the only proven alternative in the energy structure. Along with the evolution of man form primitive stage to the present civilisation, the wind energy has also moved with time from its ancient period to the present stage of sophistication which can be adopted to various needs like water pumping and power generation. (author)

  20. Particle deformation during stirred media milling

    Science.gov (United States)

    Hamey, Rhye Garrett

    Production of high aspect ratio metal flakes is an important part of the paint and coating industry. The United States Army also uses high aspect ratio metal flakes of a specific dimension in obscurant clouds to attenuate infrared radiation. The most common method for their production is by milling a metal powder. Ductile metal particles are initially flattened in the process increasing the aspect ratio. As the process continues, coldwelding of metal flakes can take place increasing the particle size and decreasing the aspect ratio. Extended milling times may also result in fracture leading to a further decrease in the particle size and aspect ratio. Both the coldwelding of the particles and the breakage of the particles are ultimately detrimental to the materials performance. This study utilized characterization techniques, such as, light scattering and image analysis to determine the change in particle size as a function of milling time and parameters. This study proved that a fundamental relationship between the milling parameters and particle deformation could be established by using Hertz's theory to calculate the stress acting on the aluminum particles. The study also demonstrated a method by which milling efficiency could be calculated, based on the amount of energy required to cause particle deformation. The study found that the particle deformation process could be an energy efficient process at short milling times with milling efficiency as high as 80%. Finally, statistical design of experiment was used to obtain a model that related particle deformation to milling parameters, such as, rotation rate and milling media size.

  1. Acceleration of coupled granular flow and fluid flow simulations in pebble bed energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yanheng, E-mail: liy19@rpi.edu [Department of Mechanical, Aerospace, and Nuclear Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY (United States); Ji, Wei, E-mail: jiw2@rpi.edu [Department of Mechanical, Aerospace, and Nuclear Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY (United States)

    2013-05-15

    Highlights: ► Fast simulation of coupled pebble flow and coolant flow in PBR systems is studied. ► Dimension reduction based on axisymmetric geometry shows significant speedup. ► Relaxation of coupling frequency is investigated and an optimal range is determined. ► A total of 80% efficiency increase is achieved by the two fast strategies. ► Fast strategies can be applied to simulating other general fluidized bed systems. -- Abstract: Fast and accurate approaches to simulating the coupled particle flow and fluid flow are of importance to the analysis of large particle-fluid systems. This is especially needed when one tries to simulate pebble flow and coolant flow in Pebble Bed Reactor (PBR) energy systems on a routine basis. As one of the Generation IV designs, the PBR design is a promising nuclear energy system with high fuel performance and inherent safety. A typical PBR core can be modeled as a particle-fluid system with strong interactions among pebbles, coolants and reactor walls. In previous works, the coupled Discrete Element Method (DEM)-Computational Fluid Dynamics (CFD) approach has been investigated and applied to modeling PBR systems. However, the DEM-CFD approach is computationally expensive due to large amounts of pebbles in PBR systems. This greatly restricts the PBR analysis for the real time prediction and inclusion of more physics. In this work, based on the symmetry of the PBR geometry and the slow motion characteristics of the pebble flow, two acceleration strategies are proposed. First, a simplified 3D-DEM/2D-CFD approach is proposed to speed up the DEM-CFD simulation without loss of accuracy. Pebble flow is simulated by a full 3D DEM, while the coolant flow field is calculated with a 2D CFD simulation by averaging variables along the annular direction in the cylindrical and annular geometries. Second, based on the slow motion of pebble flow, the impact of the coupling frequency on the computation accuracy and efficiency is

  2. Acceleration of coupled granular flow and fluid flow simulations in pebble bed energy systems

    International Nuclear Information System (INIS)

    Li, Yanheng; Ji, Wei

    2013-01-01

    Highlights: ► Fast simulation of coupled pebble flow and coolant flow in PBR systems is studied. ► Dimension reduction based on axisymmetric geometry shows significant speedup. ► Relaxation of coupling frequency is investigated and an optimal range is determined. ► A total of 80% efficiency increase is achieved by the two fast strategies. ► Fast strategies can be applied to simulating other general fluidized bed systems. -- Abstract: Fast and accurate approaches to simulating the coupled particle flow and fluid flow are of importance to the analysis of large particle-fluid systems. This is especially needed when one tries to simulate pebble flow and coolant flow in Pebble Bed Reactor (PBR) energy systems on a routine basis. As one of the Generation IV designs, the PBR design is a promising nuclear energy system with high fuel performance and inherent safety. A typical PBR core can be modeled as a particle-fluid system with strong interactions among pebbles, coolants and reactor walls. In previous works, the coupled Discrete Element Method (DEM)-Computational Fluid Dynamics (CFD) approach has been investigated and applied to modeling PBR systems. However, the DEM-CFD approach is computationally expensive due to large amounts of pebbles in PBR systems. This greatly restricts the PBR analysis for the real time prediction and inclusion of more physics. In this work, based on the symmetry of the PBR geometry and the slow motion characteristics of the pebble flow, two acceleration strategies are proposed. First, a simplified 3D-DEM/2D-CFD approach is proposed to speed up the DEM-CFD simulation without loss of accuracy. Pebble flow is simulated by a full 3D DEM, while the coolant flow field is calculated with a 2D CFD simulation by averaging variables along the annular direction in the cylindrical and annular geometries. Second, based on the slow motion of pebble flow, the impact of the coupling frequency on the computation accuracy and efficiency is

  3. Online SAG Mill Pluse Measurement and Optimization

    Energy Technology Data Exchange (ETDEWEB)

    Raj Rajamani; Jose Delgadillo; Vishal Duriseti

    2007-06-30

    The grinding efficiency of semi autogenous milling or ball milling depends on the tumbling motion of the total charge within the mill. Utilization of this tumbling motion for efficient breakage of particles depends on the conditions inside the mill. However, any kind of monitoring device to measure the conditions inside the mill shell during operation is virtually impossible due to the severe environment presented by the tumbling charge. An instrumented grinding ball, which is capable of surviving a few hours and transmitting the impacts it experiences, is proposed here. The spectrum of impacts collected over 100 revolutions of the mills presents the signature of the grinding environment inside mill. This signature could be effectively used to optimize the milling performance by investigating this signature's relation to mill product size, mill throughput, make-up ball size, mill speed, liner profile and ball addition rates. At the same time, it can also be used to design balls and liner systems that can survive longer in the mill. The technological advances made in electronics and communication makes this leap in instrumentation certainly viable. Hence, the instrumented grinding ball offers the ability to qualitatively observe and optimize the milling environment. An instrumented load cell package that can measure the force of impacts inside the grinding chamber of a mill is developed here. The signal from the instrumented load cell package is interpreted in terms of a histogram termed as an impact spectrum which is a plot of the number of impacts at a specific energy level against the energy. It reflects on the average force regime of the mill. The instrumented load cell package was calibrated against the ultra fast load cell which has been unanimously accepted as a standard to measure single breakage events. The load cell package was successfully used to produce impact spectra in an 8.5 inch lab scale mill. The mill speed and the ball size were varied to

  4. Large-scale instability in interacting dark energy and dark matter fluids

    International Nuclear Information System (INIS)

    Väliviita, Jussi; Majerotto, Elisabetta; Maartens, Roy

    2008-01-01

    If dark energy interacts with dark matter, this gives a new approach to the coincidence problem. But interacting dark energy models can suffer from pathologies. We consider the case where the dark energy is modelled as a fluid with constant equation of state parameter w. Non-interacting constant-w models are well behaved in the background and in the perturbed universe. But the combination of constant w and a simple interaction with dark matter leads to an instability in the dark sector perturbations at early times: the curvature perturbation blows up on super-Hubble scales. Our results underline how important it is to carefully analyse the relativistic perturbations when considering models of coupled dark energy. The instability that we find has been missed in some previous work where the perturbations were not consistently treated. The unstable mode dominates even if adiabatic initial conditions are used. The instability also arises regardless of how weak the coupling is. This non-adiabatic instability is different from previously discovered adiabatic instabilities on small scales in the strong-coupling regime

  5. Seismic energy dissipation study of linear fluid viscous dampers in steel structure design

    Directory of Open Access Journals (Sweden)

    A. Ras

    2016-09-01

    Full Text Available Energy dissipation systems in civil engineering structures are sought when it comes to removing unwanted energy such as earthquake and wind. Among these systems, there is combination of structural steel frames with passive energy dissipation provided by Fluid Viscous Dampers (FVD. This device is increasingly used to provide better seismic protection for existing as well as new buildings and bridges. A 3D numerical investigation is done considering the seismic response of a twelve-storey steel building moment frame with diagonal FVD that have linear force versus velocity behaviour. Nonlinear time history, which is being calculated by Fast nonlinear analysis (FNA, of Boumerdes earthquake (Algeria, May 2003 is considered for the analysis and carried out using the SAP2000 software and comparisons between unbraced, braced and damped structure are shown in a tabulated and graphical format. The results of the various systems are studied to compare the structural response with and without this device of the energy dissipation thus obtained. The conclusions showed the formidable potential of the FVD to improve the dissipative capacities of the structure without increasing its rigidity. It is contributing significantly to reduce the quantity of steel necessary for its general stability.

  6. Structural characterization and Mössbauer studies of nanocrystalline Fe{sub 60}Ni{sub 20}Cr{sub 10}B{sub 10} alloy prepared by high energy ball milling

    Energy Technology Data Exchange (ETDEWEB)

    Slimi, M., E-mail: msrammeh@yahoo.fr [Laboratoire de Chimie Inorganique, UR-11-ES-73, université de Sfax, B.P. 1171, 3000 Sfax (Tunisia); Azabou, M. [Laboratoire de Chimie Inorganique, UR-11-ES-73, université de Sfax, B.P. 1171, 3000 Sfax (Tunisia); Suñol, J.J. [Departament de Fisica, Universitat de Girona, Campus Montilivi, Girona 17071 (Spain); Khitouni, M. [Laboratoire de Chimie Inorganique, UR-11-ES-73, université de Sfax, B.P. 1171, 3000 Sfax (Tunisia); Greneche, J.M. [LUNAM, Institut des Molécules et Matériaux du Mans, IMMM UMR CNRS 6283, Université du Maine, Avenue Olivier Messiaen, 72085 Le Mans Cedex 9 (France)

    2015-11-01

    Nanostructured Fe(Ni,Cr) and NiFe solid state powders were elaborated from elemental powders of Fe, Ni, Cr and B using planetary high-energy ball mill. Scanning electron microscopy (SEM) was employed to examine the morphology of the powdered samples as a function of milling time. The transformations occurring in the material during milling were studied at the atomic scale with the use of X-ray diffraction and {sup 57}Fe Mössbauer spectrometry. The thermal behavior of the milled powders was examined by differential scanning calorimetry (DSC). The results, as well as dissimilarity between calorimetric curves of the powders after 10 and 50 h of milling, indicated the formation of a nanostructured Fe(Ni,Cr) and NiFe solid solutions. - Highlights: • It is a complete study about the alloying process of a nanostructured alloy. • We establish the relation between microstructure and structure defects. • Mössbauer analysis confirms the coexistence of the bcc-Fe(Ni,Cr) and fcc-Ni(Fe) solid solutions.

  7. A non-oscillatory energy-splitting method for the computation of compressible multi-fluid flows

    Science.gov (United States)

    Lei, Xin; Li, Jiequan

    2018-04-01

    This paper proposes a new non-oscillatory energy-splitting conservative algorithm for computing multi-fluid flows in the Eulerian framework. In comparison with existing multi-fluid algorithms in the literature, it is shown that the mass fraction model with isobaric hypothesis is a plausible choice for designing numerical methods for multi-fluid flows. Then we construct a conservative Godunov-based scheme with the high order accurate extension by using the generalized Riemann problem solver, through the detailed analysis of kinetic energy exchange when fluids are mixed under the hypothesis of isobaric equilibrium. Numerical experiments are carried out for the shock-interface interaction and shock-bubble interaction problems, which display the excellent performance of this type of schemes and demonstrate that nonphysical oscillations are suppressed around material interfaces substantially.

  8. Static black hole and vacuum energy: thin shell and incompressible fluid

    Science.gov (United States)

    Ho, Pei-Ming; Matsuo, Yoshinori

    2018-03-01

    With the back reaction of the vacuum energy-momentum tensor consistently taken into account, we study static spherically symmetric black-hole-like solutions to the semi-classical Einstein equation. The vacuum energy is assumed to be given by that of 2-dimensional massless scalar fields, as a widely used model in the literature for black holes. The solutions have no horizon. Instead, there is a local minimum in the radius. We consider thin shells as well as incompressible fluid as the matter content of the black-hole-like geometry. The geometry has several interesting features due to the back reaction of vacuum energy. In particular, Buchdahl's inequality can be violated without divergence in pressure, even if the surface is below the Schwarzschild radius. At the same time, the surface of the star can not be far below the Schwarzschild radius for a density not much higher than the Planck scale, and the proper distance from its surface to the origin can be very short even for very large Schwarzschild radius. The results also imply that, contrary to the folklore, in principle the Boulware vacuum can be physical for black holes.

  9. Investigation and Optimisation of a Discrete Fluid Power PTO-system for Wave Energy Converters

    DEFF Research Database (Denmark)

    Hansen, Anders Hedegaard

    recently focused research on improving the power take off (PTO) system converting the mechanical motion of the floats into electricity. This has brought attention to discrete fluid power (DFP) technology, especially secondary controlled common pressure rail systems. A novel discrete PTO-system has been...... investigation show how the wave climate naturally influence the optimal system configuration yielding maximal energy output, and how one may choose the system configuration based on the installation site. The switching manifold is the control element of the secondary controlled force system. The force....... Involvement in designing, installation and control of a full scale PTO test-bench has been under-taken parallel to the theoretical work. Preliminary force switching tests have been conducted to investigate the influence of valve switching time on the dynamic behaviour of the PTO-system. The results...

  10. Associations of fatty acids in cerebrospinal fluid with peripheral glucose concentrations and energy metabolism.

    Directory of Open Access Journals (Sweden)

    Reiner Jumpertz

    Full Text Available Rodent experiments have emphasized a role of central fatty acid (FA species, such as oleic acid, in regulating peripheral glucose and energy metabolism. Thus, we hypothesized that central FAs are related to peripheral glucose regulation and energy expenditure in humans. To test this we measured FA species profiles in cerebrospinal fluid (CSF and plasma of 32 individuals who stayed in our clinical inpatient unit for 6 days. Body composition was measured by dual energy X-ray absorptiometry and glucose regulation by an oral glucose test (OGTT followed by measurements of 24 hour (24EE and sleep energy expenditure (SLEEP as well as respiratory quotient (RQ in a respiratory chamber. CSF was obtained via lumbar punctures; FA concentrations were measured by liquid chromatography/mass spectrometry. As expected, FA concentrations were higher in plasma compared to CSF. Individuals with high concentrations of CSF very-long-chain saturated FAs had lower rates of SLEEP. In the plasma moderate associations of these FAs with higher 24EE were observed. Moreover, CSF monounsaturated long-chain FA (palmitoleic and oleic acid concentrations were associated with lower RQs and lower glucose area under the curve during the OGTT. Thus, FAs in the CSF strongly correlated with peripheral metabolic traits. These physiological parameters were most specific to long-chain monounsaturated (C16:1, C18:1 and very-long-chain saturated (C24:0, C26:0 FAs.Together with previous animal experiments these initial cross-sectional human data indicate that central FA species are linked to peripheral glucose and energy homeostasis.

  11. Focused ion beam milling of carbon fibres

    International Nuclear Information System (INIS)

    Huson, Mickey G.; Church, Jeffrey S.; Hillbrick, Linda K.; Woodhead, Andrea L.; Sridhar, Manoj; Van De Meene, Allison M.L.

    2015-01-01

    A focused ion beam has been used to mill both individual carbon fibres as well as fibres in an epoxy composite, with a view to preparing flat surfaces for nano-indentation. The milled surfaces have been assessed for damage using scanning probe microscopy nano-indentation and Raman micro-probe analysis, revealing that FIB milling damages the carbon fibre surface and covers surrounding areas with debris of disordered carbon. The debris is detected as far as 100 μm from the milling site. The energy of milling as well as the orientation of the beam was varied and shown to have an effect when assessed by Raman spectroscopy. - Highlights: • Focused ion beam (FIB) milling was used to mill flat surfaces on carbon fibres. • Raman spectroscopy showed amorphous carbon was generated during FIB milling. • The amorphous debris is detected as far as 100 μm from the milling site. • This surface degradation was confirmed by nano-indentation experiments.

  12. A low-energy β-function in a finite super-Yang-Mills model with multiple mass scales

    International Nuclear Information System (INIS)

    Foda, O.; Helayel-Neto, J.A.

    1985-01-01

    We compute the one-loop contribution to the low-energy light-fermion gauge coupling in a finite supersymmetric gauge theory with two mass scales: a heavy mass that breaks an initial N=4 supersymmetry down to N=2, but respects the finiteness, and a light mass that, for simplicity, is set to zero. We find that coupling grows with the mass of the heavy intermediate states. Hence the latter do not decouple at low energies, leading to large logarithms that invalidate low-energy perturbation theory. Consequently, further manipulations are required to obtain a meaningful perturbative expansion. Enforcing decoupling through finite renormalizations, that absorb the heavy mass effects into a redefinition of the parameters of the lagrangian, introduces an arbitrary subtraction mass μ. The requirement that the S-matrix elements be independent of μ leads to a non-trivial renormalization-group equation for the low-energy theory, with a non-vanishing β-function. (orig.)

  13. Low-energy. beta. -function in a finite super-Yang-Mills model with multiple mass scales

    Energy Technology Data Exchange (ETDEWEB)

    Foda, O.; Helayel-Neto, J.A. (International Centre for Theoretical Physics, Trieste (Italy))

    1985-02-14

    We compute the one-loop contribution to the low-energy light-fermion gauge coupling in a finite supersymmetric gauge theory with two mass scales: a heavy mass that breaks an initial N=4 supersymmetry down to N=2, but respects the finiteness, and a light mass that, for simplicity, is set to zero. We find that coupling grows with the mass of the heavy intermediate states. Hence the latter do not decouple at low energies, leading to large logarithms that invalidate low-energy perturbation theory. Consequently, further manipulations are required to obtain a meaningful perturbative expansion. Enforcing decoupling through finite renormalizations, that absorb the heavy mass effects into a redefinition of the parameters of the lagrangian, introduces an arbitrary subtraction mass ..mu... The requirement that the S-matrix elements be independent of ..mu.. leads to a non-trivial renormalization-group equation for the low-energy theory, with a non-vanishing ..beta..-function.

  14. Mill power for high-pressure grinding rolls in coal grinding

    Energy Technology Data Exchange (ETDEWEB)

    Austin, L.G. [Pennsylvania State University, University Park, PA (United States). Mineral Processing Section

    1997-08-01

    Using an instrumented laboratory high-pressure grinding rolls mill, the grinding force, gap dimension, mass flow rate and net mill power were measured for size coals and a crystalline quartz. A technique was developed to estimate the compressive stress-strain curves for compression of the materials in the mill plus the effects of elastic decompression. To reconcile the mill power and grinding pressure results, it was necessary to allow for the energy recovery on decompression. No clear correlation was obtained between the form of the stress-strain curves or the variation of specific mill power factor with the Hardgrove grindability index (HGI), although coals with the lowest and highest HGIs (i.e., 44 and 106) gave results significantly different from the other coals. Feeds below 140 mesh (105 {mu}m) flowed more rapidly than coarser feeds and would not build up high grinding pressures. This indicated shearing and fluid-like properties rather than compression as a locked bed. 6 refs., 9 figs., 1 app.

  15. A low-energy β-function in a finite super-Yang-Mills model with multiple mass scales

    International Nuclear Information System (INIS)

    Foda, O.; Helayel-Neto, J.A.

    1984-08-01

    We compute the one-loop contribution to the low-energy light-fermion gauge coupling in a finite supersymmetric gauge theory with two mass scales: a heavy mass that breaks an initial N=4 supersymmetry down to N=2, but respects the finiteness, and a light mass that, for simplicity, is set to zero. We find that the coupling grows with the mass of the heavy intermediate states. Hence the latter do not decouple at low energies, leading to large logarithms that invalidate low-energy perturbation theory. Consequently, further manipulations are required to obtain a meaningful perturbative expansion. Enforcing decoupling through finite renormalizations, that absorb the heavy mass effects into a redefinition of the parameters of the Lagrangian, introduces an arbitrary subtraction mass μ. The requirement that the S-matrix elements be independent of μ leads to a non-trivial renormalization-group equation for the low-energy theory, with a non-vanishing β-function. (author)

  16. Considerations of blood properties, outlet boundary conditions and energy loss approaches in computational fluid dynamics modeling.

    Science.gov (United States)

    Moon, Ji Young; Suh, Dae Chul; Lee, Yong Sang; Kim, Young Woo; Lee, Joon Sang

    2014-02-01

    Despite recent development of computational fluid dynamics (CFD) research, analysis of computational fluid dynamics of cerebral vessels has several limitations. Although blood is a non-Newtonian fluid, velocity and pressure fields were computed under the assumptions of incompressible, laminar, steady-state flows and Newtonian fluid dynamics. The pulsatile nature of blood flow is not properly applied in inlet and outlet boundaries. Therefore, we present these technical limitations and discuss the possible solution by comparing the theoretical and computational studies.

  17. Method to Produce Durable Pellets at Lower Energy Consumption Using High Moisture Corn Stover and a Corn Starch Binder in a Flat Die Pellet Mill

    Science.gov (United States)

    Tumuluru, Jaya Shankar; Conner, Craig C.; Hoover, Amber N.

    2016-01-01

    A major challenge in the production of pellets is the high cost associated with drying biomass from 30 to 10% (w.b.) moisture content. At Idaho National Laboratory, a high-moisture pelleting process was developed to reduce the drying cost. In this process the biomass pellets are produced at higher feedstock moisture contents than conventional methods, and the high moisture pellets produced are further dried in energy efficient dryers. This process helps to reduce the feedstock moisture content by about 5-10% during pelleting, which is mainly due to frictional heat developed in the die. The objective of this research was to explore how binder addition influences the pellet quality and energy consumption of the high-moisture pelleting process in a flat die pellet mill. In the present study, raw corn stover was pelleted at moistures of 33, 36, and 39% (w.b.) by addition of 0, 2, and 4% pure corn starch. The partially dried pellets produced were further dried in a laboratory oven at 70 °C for 3-4 hr to lower the pellet moisture to less than 9% (w.b.). The high moisture and dried pellets were evaluated for their physical properties, such as bulk density and durability. The results indicated that increasing the binder percentage to 4% improved pellet durability and reduced the specific energy consumption by 20-40% compared to pellets with no binder. At higher binder addition (4%), the reduction in feedstock moisture during pelleting was 510 kg/m3 and >98%, respectively, and the percent fine particles generated was reduced to <3%. PMID:27340875

  18. Method to Produce Durable Pellets at Lower Energy Consumption Using High Moisture Corn Stover and a Corn Starch Binder in a Flat Die Pellet Mill.

    Science.gov (United States)

    Tumuluru, Jaya Shankar; Conner, Craig C; Hoover, Amber N

    2016-06-15

    A major challenge in the production of pellets is the high cost associated with drying biomass from 30 to 10% (w.b.) moisture content. At Idaho National Laboratory, a high-moisture pelleting process was developed to reduce the drying cost. In this process the biomass pellets are produced at higher feedstock moisture contents than conventional methods, and the high moisture pellets produced are further dried in energy efficient dryers. This process helps to reduce the feedstock moisture content by about 5-10% during pelleting, which is mainly due to frictional heat developed in the die. The objective of this research was to explore how binder addition influences the pellet quality and energy consumption of the high-moisture pelleting process in a flat die pellet mill. In the present study, raw corn stover was pelleted at moistures of 33, 36, and 39% (w.b.) by addition of 0, 2, and 4% pure corn starch. The partially dried pellets produced were further dried in a laboratory oven at 70 °C for 3-4 hr to lower the pellet moisture to less than 9% (w.b.). The high moisture and dried pellets were evaluated for their physical properties, such as bulk density and durability. The results indicated that increasing the binder percentage to 4% improved pellet durability and reduced the specific energy consumption by 20-40% compared to pellets with no binder. At higher binder addition (4%), the reduction in feedstock moisture during pelleting was 510 kg/m(3) and >98%, respectively, and the percent fine particles generated was reduced to <3%.

  19. The effect of rotational and translational energy exchange on tracer diffusion in rough hard sphere fluids.

    Science.gov (United States)

    Kravchenko, Olga; Thachuk, Mark

    2011-03-21

    A study is presented of tracer diffusion in a rough hard sphere fluid. Unlike smooth hard spheres, collisions between rough hard spheres can exchange rotational and translational energy and momentum. It is expected that as tracer particles become larger, their diffusion constants will tend toward the Stokes-Einstein hydrodynamic result. It has already been shown that in this limit, smooth hard spheres adopt "slip" boundary conditions. The current results show that rough hard spheres adopt boundary conditions proportional to the degree of translational-rotational energy exchange. Spheres for which this exchange is the largest adopt "stick" boundary conditions while those with more intermediate exchange adopt values between the "slip" and "stick" limits. This dependence is found to be almost linear. As well, changes in the diffusion constants as a function of this exchange are examined and it is found that the dependence is stronger than that suggested by the low-density, Boltzmann result. Compared with smooth hard spheres, real molecules undergo inelastic collisions and have attractive wells. Rough hard spheres model the effect of inelasticity and show that even without the presence of attractive forces, the boundary conditions for large particles can deviate from "slip" and approach "stick."

  20. Biomass torrefaction mill

    Science.gov (United States)

    Sprouse, Kenneth M.

    2016-05-17

    A biomass torrefaction system includes a mill which receives a raw biomass feedstock and operates at temperatures above 400 F (204 C) to generate a dusty flue gas which contains a milled biomass product.

  1. Novel fabrication of solid-state NaBH 4/Ru-based catalyst composites for hydrogen evolution using a high-energy ball-milling process

    Science.gov (United States)

    Liu, Cheng-Hong; Chen, Bing-Hung; Hsueh, Chan-Li; Ku, Jie-Ren; Tsau, Fanghei

    Solid-state NaBH 4/Ru-based catalyst composites have been fabricated for hydrogen generation through a high-energy ball-milling process, providing uniform dispersion of resin-supported Ru 3+ catalysts among pulverized NaBH 4 (SBH) particles, so as to increase the contacts of SBH with active catalytic sites. Consequently, the gravimetric hydrogen storage capacity as high as 7.3 wt% could be achieved by utilizing water as a limiting reagent to overcome the issue of deactivated catalysts whose active sites are often blocked by precipitates caused by limited NaBO 2 solubility occurring in conventional aqueous SBH systems for hydrogen productions. Products of hydrolyzed SBH that greatly influence the gravimetric H 2 storage capacity are found to be most likely NaBO 2·2H 2O and NaBO 2·4H 2O from SBH/H 2O reacting systems with initial weight ratios, SBH/H 2O = 1/2 and 1/10, respectively, according to the TGA and XRD analyses.

  2. Effect of milling time on the formation of carbon nanotube by ...

    Indian Academy of Sciences (India)

    CNTs) in this study. In this method, graphite powders in the elemental form were firstly exposed to milling process in high-energy ball milling and then the milled powders were annealed at high temperatures. As a result of milling of the graphite, ...

  3. Japan steel mill perspective

    Energy Technology Data Exchange (ETDEWEB)

    Murase, K. [Kobe Steel Ltd., Tokyo (Japan)

    2004-07-01

    The international and Japan's steel industry, the coking coal market, and Japan's expectations from Canada's coal industry are discussed. Japan's steel mills are operating at full capacity. Crude steel production for the first half of 2004 was 55.8 million tons. The steel mills are profitable, but costs are high, and there are difficulties with procuring raw materials. Japan is trying to enhance the quality of coke, in order to achieve higher productivity in the production of pig iron. Economic growth is rising disproportionately in the BRICs (Brazil, Russia, India, and China), with a large increase in coking coal demand from China. On the supply side, there are several projects underway in Australia and Canada to increase production. These include new developments by Elk Valley Coal Corporation, Grande Cache Coal, Western Canadian Coal, and Northern Energy and Mining in Canada. The Elga Mine in the far eastern part of Russia is under development. But the market is expected to remain tight for some time. Japan envisions Canadian coal producers will provide a stable coal supply, expansion of production and infrastructure capabilities, and stabilization of price. 16 slides/overheads are included.

  4. The effect of the addition of the elements Ni, Zn and Co in a composite AlTiO2 obtained by high-energy milling and sintering process

    International Nuclear Information System (INIS)

    Carvalho, C.O. de; Coelho, R.E.; Conrado, L.C.; Nascimento, C.S.; Teixeira, C.A.; Mendonca, E.S.

    2016-01-01

    The present work use aluminum scrap with addition of TiO 2 , Ni, Zn or Co to preparation and characterization of nanocomposites. The aluminum were cut and subjected to high energy milling for 2 hours at 1200rpm. The obtained powder was added to TiO 2 , Ni, Zn or Co in a nominal composition 97Al-2TiO 2 -1X (X = Ni, Zn or Co) (weight %) and again, the mixture was subjected to milling for 1 hour at 1000rpm. Grinding powders were hot pressed in the closed die and then removed; the compressed were sintered at 950°C in a tubular furnace N 2 passing atmosphere. The samples obtained were characterized by Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS) and X-ray Diffraction (XRD). The results of SEM images showed a very refined microstructure and an aluminum matrix without porosity. (author)

  5. Studies of superspin glass state and AC-losses in La{sub 0.7}Sr{sub 0.3}MnO{sub 3} nanoparticles obtained by high-energy ball-milling

    Energy Technology Data Exchange (ETDEWEB)

    Phong, P.T., E-mail: ptphong.nh@khanhhoa.edu.vn [Department of Advanced Materials Chemistry, Dongguk University-Gyeongju, 707 Suckjang-dong, Gyeongbuk, Gyeongju-Si 780-714 (Korea, Republic of); Nha Trang Pedagogic College, 1 Nguyen Chanh Street, Khanh Hoa Province, Nha Trang City (Viet Nam); Manh, D.H. [Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Cau Giay District, Ha Noi City (Viet Nam); Nguyen, L.H. [Nha Trang Pedagogic College, 1 Nguyen Chanh Street, Khanh Hoa Province, Nha Trang City (Viet Nam); Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Cau Giay District, Ha Noi City (Viet Nam); Tung, D.K. [Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Cau Giay District, Ha Noi City (Viet Nam); Phuc, N.X., E-mail: phucnx1949@gmail.com [Nha Trang Pedagogic College, 1 Nguyen Chanh Street, Khanh Hoa Province, Nha Trang City (Viet Nam); Lee, I.-J., E-mail: lij@dongguk.ac.kr [Department of Advanced Materials Chemistry, Dongguk University-Gyeongju, 707 Suckjang-dong, Gyeongbuk, Gyeongju-Si 780-714 (Korea, Republic of)

    2014-11-15

    Single-phase perovskite compound La{sub 0.7}Sr{sub 0.3}MnO{sub 3} was synthesized by a high-energy ball milling method. Nanoparticle nature of this manganite with the average particle diameter of 11 nm was revealed from structure and morphology characterizations. The results of ac magnetic susceptibility measurements show that the system can be described as an ensemble of interacting magnetic nanoparticles, which indicates that the dipole–dipole interactions are strong enough to create superspin glass state in the sample. Furthermore, the specific loss power which is exhausted on the irradiation of an ensemble of particles with a magnetic field has been calculated and measured experimentally. - Highlights: • LSMO nanopowder was prepared by the high-energy ball-milling method. • The superspin glass state of LSMO nanopowder was studied. • The SLP has been calculated and measured experimentally.

  6. The Logotropic Dark Fluid as a unification of dark matter and dark energy

    Directory of Open Access Journals (Sweden)

    Pierre-Henri Chavanis

    2016-07-01

    Full Text Available We propose a heuristic unification of dark matter and dark energy in terms of a single “dark fluid” with a logotropic equation of state P=Aln⁡(ρ/ρP, where ρ is the rest-mass density, ρP=5.16×1099gm−3 is the Planck density, and A is the logotropic temperature. The energy density ϵ is the sum of a rest-mass energy term ρc2∝a−3 mimicking dark matter and an internal energy term u(ρ=−P(ρ−A=3Aln⁡a+C mimicking dark energy (a is the scale factor. The logotropic temperature is approximately given by A≃ρΛc2/ln⁡(ρP/ρΛ≃ρΛc2/[123ln⁡(10], where ρΛ=6.72×10−24gm−3 is the cosmological density and 123 is the famous number appearing in the ratio ρP/ρΛ∼10123 between the Planck density and the cosmological density. More precisely, we obtain A=2.13×10−9gm−1s−2 that we interpret as a fundamental constant. At the cosmological scale, our model fulfills the same observational constraints as the ΛCDM model (they will differ in about 25 Gyrs when the logotropic universe becomes phantom. However, the logotropic dark fluid has a nonzero speed of sound and a nonzero Jeans length which, at the beginning of the matter era, is about λJ=40.4pc, in agreement with the minimum size of the dark matter halos observed in the universe. The existence of a nonzero Jeans length may solve the missing satellite problem. At the galactic scale, the logotropic pressure balances the gravitational attraction, providing halo cores instead of cusps. This may solve the cusp problem. The logotropic equation of state generates a universal rotation curve that agrees with the empirical Burkert profile of dark matter halos up to the halo radius. In addition, it implies that all the dark matter halos have the same surface density Σ0=ρ0rh=141M⊙/pc2 and that the mass of dwarf galaxies enclosed within a sphere of fixed radius ru=300pc has the same value M300=1.93×107M⊙, in remarkable agreement with the observations [Donato et al. [10

  7. Freezing point and solid-liquid interfacial free energy of Stockmayer dipolar fluids: a molecular dynamics simulation study.

    Science.gov (United States)

    Wang, Jun; Apte, Pankaj A; Morris, James R; Zeng, Xiao Cheng

    2013-09-21

    Stockmayer fluids are a prototype model system for dipolar fluids. We have computed the freezing temperatures of Stockmayer fluids at zero pressure using three different molecular-dynamics simulation methods, namely, the superheating-undercooling method, the constant-pressure and constant-temperature two-phase coexistence method, and the constant-pressure and constant-enthalpy two-phase coexistence method. The best estimate of the freezing temperature (in reduced unit) for the Stockmayer (SM) fluid with the dimensionless dipole moment μ*=1, √2, √3 is 0.656 ± 0.001, 0.726 ± 0.002, and 0.835 ± 0.005, respectively. The freezing temperature increases with the dipolar strength. Moreover, for the first time, the solid-liquid interfacial free energies γ of the fcc (111), (110), and (100) interfaces are computed using two independent methods, namely, the cleaving-wall method and the interfacial fluctuation method. Both methods predict that the interfacial free energy increases with the dipole moment. Although the interfacial fluctuation method suggests a weaker interfacial anisotropy, particularly for strongly dipolar SM fluids, both methods predicted the same trend of interfacial anisotropy, i.e., γ100 > γ110 > γ111.

  8. Multi-Fluid Geothermal Energy Systems: Using CO2 for Dispatchable Renewable Power Generation and Grid Stabilization

    Science.gov (United States)

    Buscheck, T. A.; Bielicki, J. M.; Randolph, J.; Chen, M.; Hao, Y.; Sun, Y.

    2013-12-01

    Abstract We present an approach to use CO2 to (1) generate dispatchable renewable power that can quickly respond to grid fluctuations and be cost-competitive with natural gas, (2) stabilize the grid by efficiently storing large quantities of energy, (3) enable seasonal storage of solar thermal energy for grid integration, (4) produce brine for power-plant cooling, all which (5) increase CO2 value, rendering CO2 capture to be commerically viable, while (6) sequestering huge quantities of CO2. These attributes reduce carbon intensity of electric power, and enable cost-competitive, dispatchable power from major sources of renewable energy: wind, solar, and geothermal. Conventional geothermal power systems circulate brine as the working fluid to extract heat, but the parasitic power load for this circulation can consume a large portion of gross power output. Recently, CO2 has been considered as a working fluid because its advantageous properties reduce this parasitic loss. We expand on this idea by using multiple working fluids: brine, CO2, and N2. N2 can be separated from air at lower cost than captured CO2, it is not corrosive, and it will not react with the formation. N2 also can improve the economics of energy production and enable energy storage, while reducing operational risk. Extracting heat from geothermal reservoirs often requires submersible pumps to lift brine, but these pumps consume much of the generated electricity. In contrast, our approach drives fluid circulation by injecting supplemental, compressible fluids (CO2, and N2) with high coefficients of thermal expansion. These fluids augment reservoir pressure, produce artesian flow at the producers, and reduce the parasitic load. Pressure augmentation is improved by the thermosiphon effect that results from injecting cold/dense CO2 and N2. These fluids are heated to reservoir temperature, greatly expand, and increase the artesian flow of brine and supplemental fluid at the producers. Rather than using

  9. Coupled Fluid, Energy, and Solute Transport (CFEST) model: Formulation and user's manual

    International Nuclear Information System (INIS)

    Gupta, S.K.; Cole, C.R.; Kincaid, C.T.; Monti, A.M.

    1987-10-01

    The CFEST (Coupled Fluid, Energy, and Solute Transport) code has been developed to analyze coupled hydrologic, thermal, and solute transport processes. It treats single-pahse Darcy ground-water flow in a horizontal or vertical plane, or in fully three-dimensional space under nonisothermal conditions. The code has the capability to model discontinuous and continuous layering, time-dependent and constant sources/sinks, and transient as well as steady-stae ground-water flow. The code offers a wide choice of boundary conditions such as precsribed heads, nodal injection or withdrawal, constant or spatially varying infiltration rates, and welemental source/sink. Initial conditions for the flow analysis can be prescribed pressure or hydraulic head. The heterogeneity in aquifer permeability and porosity can be described by geologic unit or explicity for given elements. Three-dimensional elelments are generated from user-defined well logs at each surface node. To facilitate interaction between disciplines, support programs are provided to plot the finite element grid, well logs, contour maps of input and output parameters, and vertical cross sections. Ground-water travel paths and times and volumetric rates from a specified point can be determined from support programs. This report includes governing partial differential equations, finite element formulation, a use's manual, verification test examples, sample problems, and source listings. 36 refs., 121 figs., 36 tabs

  10. Relationship between Energy Expenditure Related Factors and Oxidative Stress in Follicular Fluid.

    Science.gov (United States)

    Kazemi, Ashraf; Ramezanzadeh, Fatemeh; Nasr Esfahani, Mohammad Hosein; Saboor-Yaraghi, Ali Akbar; Nejat, Saharnaz Nejat; Rahimi-Foroshani, Abbas

    2014-07-01

    This study evaluated the impact of body mass index (BMI), total calorie intake and physical activity (PA) as energy expenditure related factors on oxidative stress (OS) in follicular fluid (FF). This prospective study conducted on 219 infertile women. We evaluated patients' BMI, total calorie intake and PA in their assisted reproduction treatment cycles. Malondialdehyde (MDA) and total antioxidant capacity (TAC) in pooled FF at oocyte retrieval were additionally assessed. There was no relation between OS biomarkers to total calorie intake and PA. The TAC levels in FF adjusted for age, duration of infertility, etiology of infertility, number of used gonadotrophin and PA showed a positive relation to BMI (p=0.001). The number of used gonadotrophin and PA had a negative relation to duration of infertility (p=0.03) and anovulation disorder as an etiology of infertility. The MDA level in FF had a positive association with anovulation disorder as the etiology of infertility (p=0.02). MDA in FF was unaffected by BMI. Increasing age, BMI and PA do not affect OS in FF. In women with longtime infertility and those with anovulation disorder as an etiology of infertility, decreased potent antioxidant defense in the follicular microenvironment may contribute to ovarian function. Therefore antioxidant supplements may be beneficial for these groups of women.

  11. Nanoscale fluid-structure interaction: flow resistance and energy transfer between water and carbon nanotubes.

    Science.gov (United States)

    Chen, Chao; Ma, Ming; Jin, Kai; Liu, Jefferson Zhe; Shen, Luming; Zheng, Quanshui; Xu, Zhiping

    2011-10-01

    We investigate here water flow passing a single-walled carbon nanotube (CNT), through analysis based on combined atomistic and continuum mechanics simulations. The relation between drag coefficient C(D) and Reynolds number Re is obtained for a wide range of flow speed u from 5 to 600 m/s. The results suggest that Stokes law for creep flow works well for small Reynolds numbers up to 0.1 (u ≈ 100 m/s), and indicates a linear dependence between drag force and flow velocity. Significant deviation is observed at elevated Re values, which is discussed by considering the interfacial slippage, reduction of viscosity due to friction-induced local heating, and flow-induced structural vibration. We find that interfacial slippage has a limited contribution to the reduction of the resistance, and excitations of low-frequency vibration modes in the carbon nanotube play an important role in energy transfer between water and carbon nanotubes, especially at high flow speeds where drastic enhancement of the carbon nanotube vibration is observed. The results reported here reveal nanoscale fluid-structure interacting mechanisms, and lay the ground for rational design of nanofluidics and nanoelectromechanical devices operating in a fluidic environment.

  12. Model Predictive Control of a Wave Energy Converter with Discrete Fluid Power Power Take-Off System

    Directory of Open Access Journals (Sweden)

    Anders Hedegaard Hansen

    2018-03-01

    Full Text Available Wave power extraction algorithms for wave energy converters are normally designed without taking system losses into account leading to suboptimal power extraction. In the current work, a model predictive power extraction algorithm is designed for a discretized power take of system. It is shown how the quantized nature of a discrete fluid power system may be included in a new model predictive control algorithm leading to a significant increase in the harvested power. A detailed investigation of the influence of the prediction horizon and the time step is reported. Furthermore, it is shown how the inclusion of a loss model may increase the energy output. Based on the presented results it is concluded that power extraction algorithms based on model predictive control principles are both feasible and favorable for use in a discrete fluid power power take-off system for point absorber wave energy converters.

  13. Changes in body fluid and energy compartments during prolonged hunger strike.

    Science.gov (United States)

    Faintuch, J; Soriano, F G; Ladeira, J P; Janiszewski, M; Velasco, I T; Gama-Rodrigues, J J

    2000-01-01

    Prolonged total food deprivation in non-obese adults is rare, and few studies have documented body composition changes in this setting. In a group of eight hunger strikers who refused alimentation for 43 days, water and energy compartments were estimated, aiming to assess the impact of progressive starvation. Measurements included body mass index (BMI), triceps skinfold (TSF), arm muscle circumference (AMC), and bioimpedance (BIA) determinations of water, fat, lean body mass (LBM), and total resistance. Indirect calorimetry was also performed in one occasion. The age of the group was 43.3+/-6.2 years (seven males, one female). Only water, intermittent vitamins and electrolytes were ingested, and average weight loss reached 17.9%. On the last two days of the fast (43rd-44th day) rapid intravenous fluid, electrolyte, and vitamin replenishment were provided before proceeding with realimentation. Body fat decreased approximately 60% (BIA and TSF), whereas BMI reduced only 18%. Initial fat was estimated by BIA as 52.2+/-5.4% of body weight, and even on the 43rd day it was still measured as 19.7+/-3.8% of weight. TSF findings were much lower and commensurate with other anthropometric results. Water was comparatively low with high total resistance, and these findings rapidly reversed upon the intravenous rapid hydration. At the end of the starvation period, BMI (21.5+/-2.6 kg/m2) and most anthropometric determinations were still acceptable, suggesting efficient energy and muscle conservation. 1) All compartments diminished during fasting, but body fat was by far the most affected; 2) Total water was low and total body resistance comparatively elevated, but these findings rapidly reversed upon rehydration; 3) Exaggerated fat percentage estimates from BIA tests and simultaneous increase in lean body mass estimates suggested that this method was inappropriate for assessing energy compartments in the studied population; 4) Patients were not morphologically malnourished after

  14. Changes in body fluid and energy compartments during prolonged hunger strike

    Directory of Open Access Journals (Sweden)

    Faintuch Joel

    2000-01-01

    Full Text Available Prolonged total food deprivation in non-obese adults is rare, and few studies have documented body composition changes in this setting. In a group of eight hunger strikers who refused alimentation for 43 days, water and energy compartments were estimated, aiming to assess the impact of progressive starvation. Measurements included body mass index (BMI, triceps skinfold (TSF, arm muscle circumference (AMC, and bioimpedance (BIA determinations of water, fat, lean body mass (LBM, and total resistance. Indirect calorimetry was also performed in one occasion. The age of the group was 43.3±6.2 years (seven males, one female. Only water, intermittent vitamins and electrolytes were ingested, and average weight loss reached 17.9%. On the last two days of the fast (43rd-44th day rapid intravenous fluid, electrolyte, and vitamin replenishment were provided before proceeding with realimentation. Body fat decreased approximately 60% (BIA and TSF, whereas BMI reduced only 18%. Initial fat was estimated by BIA as 52.2±5.4% of body weight, and even on the 43rd day it was still measured as 19.7±3.8% of weight. TSF findings were much lower and commensurate with other anthropometric results. Water was comparatively low with high total resistance, and these findings rapidly reversed upon the intravenous rapid hydration. At the end of the starvation period, BMI (21.5±2.6 kg/m² and most anthropometric determinations were still acceptable, suggesting efficient energy and muscle conservation. Conclusions: 1 All compartments diminished during fasting, but body fat was by far the most affected; 2 Total water was low and total body resistance comparatively elevated, but these findings rapidly reversed upon rehydration; 3 Exaggerated fat percentage estimates from BIA tests and simultaneous increase in lean body mass estimates suggested that this method was inappropriate for assessing energy compartments in the studied population; 4 Patients were not morphologically

  15. Holography and noncommutative yang-mills theory

    Science.gov (United States)

    Li; Wu

    2000-03-06

    In this Letter a recently proposed gravity dual of noncommutative Yang-Mills theory is derived from the relations between closed string moduli and open string moduli recently suggested by Seiberg and Witten. The only new input one needs is a simple form of the running string tension as a function of energy. This derivation provides convincing evidence that string theory integrates with the holographical principle and demonstrates a direct link between noncommutative Yang-Mills theory and holography.

  16. Study of the sintering behavior of fine, ultrafine and nanocrystalline WC-CO mixtures obtained by high energy milling; Estudio del comportamiento durante la sinterizacion de mezclas WC-Co finas, ultrafinas y nanocristalinas obtenidas por molienda de alta energia

    Energy Technology Data Exchange (ETDEWEB)

    Salvador, M. D.; Bonache, V.; Amigo, V.; Busquets, D.

    2008-07-01

    In this work the sintering behaviour of fine, ultrafine and nanocrystalline WC-12Co mixtures obtained by high energy milling, as well commercial nano powders, have been studied, in order to evaluate the effect of the particle size and the powder processing, in the densification, microstructural development and mechanical properties of the final product. The consolidation of the mixtures has been made by uniaxial pressing and sintering in vacuum, and by hot isostatic pressing. The sintered materials have been evaluated by measures of density, hardness and indentation fracture toughness, and micro structurally characterized by optical microscopy and scanning and transmission electronic microscopy (SEM and TEM). The results show the improvements in resistant behaviour of the materials obtained from nanocrystalline powders, in spite of the grain growth experienced during the sintering. The best results were obtained for the milling nanocrystalline material, which presents values of hardness higher than 180 HV. (Author) 46 refs.

  17. Plasma sintering of ferritic steel reinforced with niobium carbide prepared by high energy milling; Sinterizacao a plasma de aco ferritico reforcado com carbeto de niobio preparado por moagem de alta energia

    Energy Technology Data Exchange (ETDEWEB)

    Silva Junior, J.F. da; Almeida, E.O.; Gomes, U.U.; Alves Junior, C.; Messias, A.P. [Universidade Federal do Rio Grande do Norte (UFRN), Natal (Brazil). Lab. de Materiais Ceramicos e Metais Especiais; Universidade Federal do Rio Grande do Norte (UFRN), Natal (Brazil). Lab. de Processamento de Materiais por Plasma

    2010-07-01

    Plasma is an ionized gas where ions are accelerated from anode to cathode surface, where the sample is placed. There are a lot of collisions on cathode surface by ions heating and sintering the sample. High energy milling (HEM) is often used to produce composite particles to be used on powder metallurgy. These particles can exhibit fine particles and high phase dispersion. This present work aim to study ferritic steels reinforced with 3%NbC prepared by HEM and sintered on plasma furnace. Ferritic steel and NbC powders were milled during 5 hours and characterized by SEM, XRD and laser scattering. Then, these composite powders were compacted in a cylindrical steel die and then sintered in a plasma furnace. Vickers microhardness tests and SEM and XRD analysis were performed on sintered samples. (author)

  18. Utilization of aluminum to obtaining a duplex type stainless steel using high energy ball milling; Obtencao de um aco inoxidavel de estrutura duplex do sistema FeMnAl processado por moagem de alta energia

    Energy Technology Data Exchange (ETDEWEB)

    Pavlak, I.E.; Cintho, O.M., E-mail: eng.igorpavlak@yahoo.com.b [Universidade Estadual de Ponta Grossa (UEPG), PR (Brazil); Capocchi, J.D.T. [Universidade de Sao Paulo (USP), SP (Brazil)

    2010-07-01

    The obtaining of stainless steel using aluminum in its composition - FeMnAl system, has been researches subject since the sixties, by good mechanical properties and resistance to oxidation presented, when compared with conventional FeNiCr stainless steel system. In another point, the aluminum and manganese are low cost then traditional elements. This work, metallic powders of iron, manganese and pure aluminum, were processed in a Spex type high-energy ball mill in nitrogen atmosphere. The milling products were compressed into pastille form and sintered under inert atmosphere. The final products were characterized by optical and electronic microscopy and microhardness test. The metallographic analysis shows a typical austenite and ferrite duplex type microstructure. The presence of these phases was confirmed according X ray diffraction analysis. (author)

  19. Fluid machinery

    International Nuclear Information System (INIS)

    Ha, Jae Hyeon; Son, Byeong Jin

    2001-04-01

    This book tells of definition and classification of fluid machinery, energy equation of incompressible fluid, principle of momentum, classification and structure of pump, size, safety of centrifugal pump, theory and operation of contraction pump, reciprocating pump, rotary pump, special pump, using of water power, classification of water turbine, impulse water turbine, reaction water turbine, pump water turbine, liquid movement apparatus, fluid type control machinery and solid and gas type pneumatic machine.

  20. FM Interviews: Stephanie Mills

    OpenAIRE

    Valauskas, Edward

    2002-01-01

    Stephanie Mills is an author, editor, lecturer and ecological activist who has concerned herself with the fate of the earth and humanity since 1969, when her commencement address at Mills College in Oakland, Calif., drew the attention of a nation. Her speech, which the New York Times called "perhaps the most anguished statement" of the year's crop of valedictory speeches, predicted a bleak future. According to Mills, humanity was destined for suicide, the result of overpopulation and overuse ...

  1. Prediction of mill performance

    Energy Technology Data Exchange (ETDEWEB)

    P.A. Bennett [CoalTech Pty Ltd. (Australia)

    2005-07-01

    This Australian Coal Association Research Program (ACARP) project aimed to demonstrate that the Hardgrove Grindability Index (HGI) coupled with standard Petrographic Analysis can be used to greatly improve the prediction of mill power requirements, mill throughput and product size. The project examined the mill test data from ACIRL's pilot scale vertical spindle mill on 96 coals. A total of 360 mill tests, conducted under a wide range of throughputs, roll pressures and classifier settings, were included into the data set. The mill performance of maceral groups or microlithotypes was assumed to be additive, that is, each maceral group or microlithotype behaved independently and a size fraction of the product PF was the volume weighted sum of the petrographic components of that size fraction. Based on this assumption it was possible to determine the size distribution of the product PF, for a wide range of milling conditions, based solely on petrographic analysis. Microlithotypes were not determined directly but were estimated from the maceral analysis. The size distribution of individual maceral groups or microlithotypes can also be estimated based on developed correlations. Size distribution determined from petrographic analysis proved to be a better estimate than that determined from the HGI. Mill power can be estimated from petrographic analysis, but the HGI was found to be a better predictor of mill power. 19 refs., 4 figs., 1 tab.

  2. Shear Thickening Fluid (STF) – Enhanced Textiles for Impact Energy Dissipation

    Data.gov (United States)

    National Aeronautics and Space Administration — The rheological behavior of some liquids can lead to the creation of materials with very unique properties. Shear thickening fluids (STFs), also known as dilatants,...

  3. Neural Network Modeling of Cutting Fluid Impact on Energy Consumption during Turning

    Directory of Open Access Journals (Sweden)

    M. Bachraty

    2016-06-01

    Full Text Available This paper presents a part of research on power consumption differences between various cutting fluids used during turning operations. An attempt was made to study the possibility of artificial neural network to model the behavior function and predicting the electrical power consumption. Friction factor of examined cutting fluids was also measured to describe a more complete picture of investigated cutting fluids characteristics. It was discovered that wide spectrum of characteristics is present in today’s market and that artificial neural networks are suitable for purpose of modeling the power consumption of the lathe during machining. This paper could be used as a foundation for later database building where it would be possible to predict how certain cutting fluid will behave in a specific machining parameter combination.

  4. Pulp and Paper Industry Energy Bandwidth Study

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2006-08-01

    The study provides energy estimates for the following four cases: current average mill energy consumption, state-of-the-art art mill energy consumption, mill energy consumption if advanced technologies requiring further R&D were employed, and theoretical minimum mill energy consumption.

  5. The effect of fluid viscosity on the hemodynamic energy changes during operation of the pulsatile ventricular assist device.

    Science.gov (United States)

    Ahn, Chi Bum; Son, Kuk Hui; Lee, Jung Joo; Choi, Jaesoon; Song, Seung Joon; Jung, Jae Seung; Lee, Sung Ho; Son, Ho Sung; Sun, Kyung

    2011-11-01

    Blood viscosity during operation of ventricular assist device (VAD) can be changed by various conditions such as anemia. It is known generally that the blood viscosity can affect vascular resistance and lead to change of blood flow. In this study, the effect of fluid viscosity variation on hemodynamic energy was evaluated with a pulsatile blood pump in a mock system. Six solutions were used for experiments, which were composed of water and glycerin and had different viscosities of 2, 2.5, 3, 3.5, 4, and 4.5 cP. The hemodynamic energy at the outlet cannula was measured. Experimental results showed that mean pressure was increased in accordance with the viscosity increase. When the viscosity increased, the mean pressure was also increased. However, the flow was decreased according to the viscosity increase. Energy equivalent pressure value was increased according to the viscosity-induced pressure rise; however, surplus hemodynamic energy value did not show any apparent changing trend. The hemodynamic energy made by the pulsatile VAD was affected by the viscosity of the circulating fluid. © 2011, Copyright the Authors. Artificial Organs © 2011, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  6. Investigation of structural and magnetic properties of nanocrystalline Ni{sub 0.3}Zn{sub 0.7}Fe{sub 2}O{sub 4} prepared by high energy ball milling

    Energy Technology Data Exchange (ETDEWEB)

    Jalaly, M. [Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Enayati, M.H. [Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of)], E-mail: ena78@cc.iut.ac.ir; Karimzadeh, F. [Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of)

    2009-07-08

    High energy ball milling was used to produce nanocrystalline Ni{sub 0.3}Zn{sub 0.7}Fe{sub 2}O{sub 4} ferrite from stoichiometric mixture of ZnO, NiO, Fe{sub 2}O{sub 3} powders. The structural, chemical and magnetic properties of Ni-Zn ferrite was determined by X-ray powder diffractometry (XRD), scanning electron microscopy (SEM), Fourier transmission infrared spectroscopy (FTIR), vibrating sample magnetometer (VSM) and ac susceptometer measurements. The mechanism of formation this ferrite was appeared to engage two steps: diffusion of ZnO in Fe{sub 2}O{sub 3} and formation of Zn ferrite followed by diffusion of NiO in Zn ferrite and formation of Ni-Zn ferrite. The crystallite size of final product after 60 h ball milling was estimated to be about 18 nm which increased to 30 nm after annealing at 800 deg. C for 4 h. The VSM results indicated that the magnetization did not saturate and coercivity and remanence were zero. The dynamic properties of 60 h ball milled sample were investigated by ac susceptibility using the Neel-Brown, Vogel-Fulcher and power laws for superparamagnetism/spin glass. The frequency-dependence of blocking temperature can be well described by the Vogel-Fulcher law, and fitting the experimental data with Neel-Brown model and power law give unphysical value for relaxation time.

  7. The Structure and Mechanical Properties of High-Strength Bulk Ultrafine-Grained Cobalt Prepared Using High-Energy Ball Milling in Combination with Spark Plasma Sintering

    Czech Academy of Sciences Publication Activity Database

    Marek, I.; Vojtěch, D.; Michalcová, A.; Kubatík, Tomáš František

    2016-01-01

    Roč. 9, č. 5 (2016), č. článku 391. ISSN 1996-1944 Institutional support: RVO:61389021 Keywords : ultrafine-grained material * cobalt * ball milling * spark plasma sintering * mechanical properties Subject RIV: JG - Metallurgy Impact factor: 2.654, year: 2016 www.mdpi.com/1996-1944/9/5/391/pdf

  8. Experimental and theoretical study of phase transitions under ball milling; Etude experimentale et modelisation des changements de phases sous broyage a haute energie

    Energy Technology Data Exchange (ETDEWEB)

    Pochet, P

    1997-12-31

    The aim of this work was to determine how phase transition s under ball-milling depend on the milling conditions and to find out if one can rationalize such transitions with the theory of driven alloys. We have chosen two phase transitions: the order-disorder transition in Fe Al and the precipitation-dissolution NiGe. In the case of Fe Al we have found that the steady-state long range order parameter achieved under ball milling intensity; moreover the same degree of order is achieved starting from an ordered alloy or a disordered solid solution. On the way to fully disordered state the degree of order either decreases monotonically or goes through a short lived transient state. This behaviour is reminiscent of a first order transition while the equilibrium transition is second order. All the above features are well reproduced by a simple model of driven alloys, which was originally build for alloys under irradiation. The stationary degree of order results of two competitive atomic jump mechanisms: the forced displacements induced by the shearing of the grains, and the thermally activated jumps caused by vacancies migrations. Finally we have performed atomistic simulations with a Monte Carlo kinetic algorithm, which revealed the role of the fluctuations in the intensity of the forcing. Moreover we have shown that specific atomistic mechanisms are active in a dilute NiGe solid solution which might lead to ball milling induced precipitation in under-saturated solid solution. (author). 149 refs.

  9. Pilot scale hybrid processes for olive mill wastewater treatment, energy production and water reuse: comparison between fungal and electro-coagulation pre-treatments

    International Nuclear Information System (INIS)

    Sayadi, S.

    2009-01-01

    Olive oil mill wastewaters (OMW) cause disposal problems because they contain powerful pollutants such as phenolic compounds. Complete biodegradation or removal of these compounds is hardly achieved by a single treatment method. In this work, we investigated 2 integrated technologies for the treatment of the recalcitrant contaminants of OMW, allowing water recovery and reuse for agricultural purposes. (Author)

  10. X-ray diffraction study of microstructural evolution of some ZrO{sub 2}-Y{sub 2}O{sub 3}-MgO powder mixtures induced by high-energy ball milling

    Energy Technology Data Exchange (ETDEWEB)

    Stubicar, Nada; Bermanec, Vladimir; Stubicar, Mirko; Popovic, Darko; Kaysser, Wolfgang A

    2004-10-06

    The influence of the high-energy ball milling (HEBM), at the 14xg centrifugal acceleration, on a series of compositions from the ceramic pseudo-ternary zirconia-yttria-magnesia (ZrO{sub 2}-Y{sub 2}O{sub 3}-MgO) powder system has been studied mainly by the X-ray diffraction (XRD) analysis. An extensive solid solubility of both yttria and magnesia in zirconia, as well as polymorphic phase transformation of zirconia, zirconia-based solid solutions and yttria are well-established, whereas the structure of magnesia remains almost unaffected.

  11. Fluid Mechanics and Fluid Power (FMFP)

    Indian Academy of Sciences (India)

    Amitabh Bhattacharya

    of renewable energy (e.g., via wind, hydrokinetic generators), creating low-cost healthcare (e.g., via point-of-care medical testing) and improvement of energy efficiency of fluid power systems, depends on improving our understanding of Fluid. Mechanics. Fluids are ubiquitous in both nature and technological applications, ...

  12. Peristaltic-Like Motion of the Human Fetal Right Ventricle and its Effects on Fluid Dynamics and Energy Dynamics.

    Science.gov (United States)

    Wiputra, Hadi; Lim, Guat Ling; Chua, Khong Chun; Nivetha, R; Soomar, Sanah Merchant; Biwas, Arijit; Mattar, Citra Nurfarah Zaini; Leo, Hwa Liang; Yap, Choon Hwai

    2017-10-01

    In both adult human and canine, the cardiac right ventricle (RV) is known to exhibit a peristaltic-like motion, where RV sinus (inflow region) contracts first and the infundibulum (outflow region) later, in a wave-like contraction motion. The delay in contraction between the sinus and infundibulum averaged at 15% of the cardiac cycle and was estimated to produce an intra-ventricular pressure difference of 15 mmHg. However, whether such a contractile motion occurs in human fetuses as well, its effects on hemodynamics remains unknown, and are the subject of the current study. Hemodynamic studies of fetal hearts are important as previous works showed that healthy cardiac development is sensitive to fluid mechanical forces. We performed 4D clinical ultrasound imaging on eight 20-weeks old human fetuses. In five fetal RVs, peristaltic-like contractile motion from the sinus to infundibulum ("forward peristaltic-like motion") was observed, but in one RV, peristaltic-like motion was observed from the infundibulum to sinus ("reversed peristaltic-like motion"), and two RVs contraction delay could not be determined due to poor regression fit. Next, we performed dynamic-mesh computational fluid dynamics simulations with varying extents of peristaltic-like motions for three of the eight RVs. Results showed that the peristaltic-like motion did not affect flow patterns significantly, but had significant influence on energy dynamics: increasing extent of forward peristaltic-like motion reduced the energy required for movement of fluid out of the heart during systolic ejection, while increasing extent of reversed peristaltic-like motion increased the required energy. It is currently unclear whether the peristaltic-like motion is an adaptation to reduce physiological energy expenditure, or merely an artefact of the cardiac developmental process.

  13. Energy conservation in radiation hydrodynamics. Application to the Monte-Carlo method used for photon transport in the fluid frame

    International Nuclear Information System (INIS)

    Mercier, B.; Meurant, G.; Tassart, J.

    1985-04-01

    The description of the equations in the fluid frame has been done recently. A simplification of the collision term is obtained, but the streaming term now has to include angular deviation and the Doppler shift. We choose the latter description which is more convenient for our purpose. We introduce some notations and recall some facts about stochastic kernels and the Monte-Carlo method. We show how to apply the Monte-Carlo method to a transport equation with an arbitrary streaming term; in particular we show that the track length estimator is unbiased. We review some properties of the radiation hydrodynamics equations, and show how energy conservation is obtained. Then, we apply the Monte-Carlo method explained in section 2 to the particular case of the transfer equation in the fluid frame. Finally, we describe a physical example and give some numerical results

  14. Multi-Fluid Geo-Energy Systems for Bulk and Thermal Energy Storage and Dispatchable Renewable and Low-Carbon Electricity

    Science.gov (United States)

    Buscheck, T. A.; Randolph, J.; Saar, M. O.; Hao, Y.; Sun, Y.; Bielicki, J. M.

    2014-12-01

    Integrating renewable energy sources into electricity grids requires advances in bulk and thermal energy storage technologies, which are currently expensive and have limited capacity. We present an approach that uses the huge fluid and thermal storage capacity of the subsurface to harvest, store, and dispatch energy from subsurface (geothermal) and surface (solar, nuclear, fossil) thermal resources. CO2 captured from fossil-energy systems and N2 separated from air are injected into permeable formations to store pressure, generate artesian flow of brine, and provide additional working fluids. These enable efficient fluid recirculation, heat extraction, and power conversion, while adding operational flexibility. Our approach can also store and dispatch thermal energy, which can be used to levelize concentrating solar power and mitigate variability of wind and solar power. This may allow low-carbon, base-load power to operate at full capacity, with the stored excess energy being available to addresss diurnal and seasonal mismatches between supply and demand. Concentric rings of horizontal injection and production wells are used to create a hydraulic divide to store pressure, CO2, N2, and thermal energy. Such storage can take excess power from the grid and excess thermal energy, and dispatch that energy when it is demanded. The system is pressurized and/or heated when power supply exceeds demand and depressurized when demand exceeds supply. Supercritical CO2 and N2 function as cushion gases to provide enormous pressure-storage capacity. Injecting CO2 and N2 displaces large quantities of brine, reducing the use of fresh water. Geologic CO2 storage is a crucial option for reducing CO2 emissions, but valuable uses for CO2 are needed to justify capture costs. The initial "charging" of our system requires permanently isolating large volumes of CO2 from the atmosphere and thus creates a market for its disposal. Our approach is designed for locations where a permeable

  15. Tidal energy redistribution among vertical modes in a fluid with a mid-depth pycnocline

    NARCIS (Netherlands)

    Bordois, L.; Auclair, F.; Paci, A.; Dossmann, Y.; Gerkema, T.; Nguyen, C.

    2016-01-01

    We modeled internal tide generation above a high sinusoidal ridge in a fluid with a mid-depth pycnocline and developed an original method to quantify internal tide vertical mode amplitude in two-dimensional-vertical simulations. Since lowest modes can propagate over considerable distances, while

  16. Development of an operation strategy for hydrogen production using solar PV energy based on fluid dynamic aspects

    Directory of Open Access Journals (Sweden)

    Amores Ernesto

    2017-06-01

    Full Text Available Alkaline water electrolysis powered by renewable energy sources is one of the most promising strategies for environmentally friendly hydrogen production. However, wind and solar energy sources are highly dependent on weather conditions. As a result, power fluctuations affect the electrolyzer and cause several negative effects. Considering these limiting effects which reduce the water electrolysis efficiency, a novel operation strategy is proposed in this study. It is based on pumping the electrolyte according to the current density supplied by a solar PV module, in order to achieve the suitable fluid dynamics conditions in an electrolysis cell. To this aim, a mathematical model including the influence of electrode-membrane distance, temperature and electrolyte flow rate has been developed and used as optimization tool. The obtained results confirm the convenience of the selected strategy, especially when the electrolyzer is powered by renewable energies.

  17. Characterization of Al2O3NP–Al2024 and AgCNP–Al2024 composites prepared by mechanical processing in a high energy ball mill

    International Nuclear Information System (INIS)

    Carreño-Gallardo, C.; Estrada-Guel, I.; Romero-Romo, M.; Cruz-García, R.; López-Meléndez, C.; Martínez-Sánchez, R.

    2012-01-01

    Graphical abstract: Mechanical alloying was used to produce two kinds of metal matrix composites based on 2024 aluminum alloy, the nanocomposites were reinforced with different percentages of Al 2 O 3 and Ag C nanoparticles. The content of nanoparticles has a role important on the mechanical properties of the nanocomposite. 10 h of milling time are enough to former the Al 2024 nanocomposites. The results obtained by differential scanning calorimeter show the temperatures of intermetallic precipitation, which were identified by X-ray diffraction. The results revealed that mechanical alloying is an excellent route to incorporate and distribute NP into Al 2024 . Highlights: ► Aluminum-based nanocomposites were synthesized bay milling process. ► An homogeneous nanoparticles dispersion was reached and mechanical properties were enhanced. ► Phase transformation during heating was characterized by XRD. - Abstract: Mechanical alloying was used to produce two kinds of metal matrix composites based on 2024 aluminum alloy. The nanocomposites were reinforced with different percentages of Al 2 O 3 and Ag C nanoparticles. The content of nanoparticles has an important role on the mechanical properties of the nanocomposites. A milling time of 10 h is enough to form the Al 2024 nanocomposites. The thermograms obtained by differential scanning calorimeter show the temperatures of phase precipitation, which were identified by X-ray diffraction. The results revealed that mechanical alloying is an excellent route for the incorporation and distribution of nanoparticles into Al 2024 .

  18. VOC Control in Kraft Mills; FINAL

    International Nuclear Information System (INIS)

    Zhu, J.Y.; Chai, X.-S.; Edwards, L.L.; Gu, Y.; Teja, A.S.; Kirkman, A.G.; Pfromm, P.H.; Rezac, M.E.

    2001-01-01

    The formation of volatile organic compounds (VOCs), such as methanol, in kraft mills has been an environmental concern. Methanol is soluble in water and can increase the biochemical oxygen demand. Furthermore, it can also be released into atmosphere at the process temperatures of kraft mill-streams. The Cluster Rule of the EPA now requires the control of the release of methanol in pulp and paper mills. This research program was conducted to develop a computer simulation tool for mills to predict VOC air emissions. To achieve the objective of the research program, much effort was made in the development of analytical techniques for the analysis of VOC and determination of vapor liquid partitioning coefficient of VOCs in kraft mill-streams using headspace gas chromatography. With the developed analytical tool, methanol formation in alkaline pulping was studied in laboratory to provide benchmark data of the amount of methanol formation in pulping in kraft mills and for the validation of VOC formation and vapor-liquid equilibrium submodels. Several millwide air and liquid samplings were conducted using the analytical tools developed to validate the simulation tool. The VOC predictive simulation model was developed based on the basic chemical engineering concepts, i.e., reaction kinetics, vapor liquid equilibrium, combined with computerized mass and energy balances. Four kraft mill case studies (a continuous digester, two brownstock washing lines, and a pre-evaporator system) are presented and compared with mill measurements. These case studies provide valuable, technical information for issues related to MACT I and MACT II compliance, such as condensate collection and Clean-Condensate-Alternatives (CCA)

  19. Impact behavior of a high viscosity magnetorheological fluid-based energy absorber with a radial flow mode

    Science.gov (United States)

    Fu, Benyuan; Liao, Changrong; Li, Zhuqiang; Xie, Lei; Zhang, Peng; Jian, Xiaochun

    2017-02-01

    High viscosity linear polysiloxane magnetorheological fluid (HVLP MRF) was demonstrated with excellent suspension stability. Such material is suitable for application in the magnetorheological energy absorbers (MREAs) under axial impact loading conditions. On this basis, a new energy absorber incorporating a radial valve with high magnetic field utilization and a corrugated tube is proposed. In energy absorption applications where the MREA is rarely if ever used, our MREA takes the ultra-stable HVLP MRF as controlled medium in order for a long-term stability. For MREA performing at very high shear rates where the minor losses are important contributing factors to damping, a nonlinear analytical model, based on the Herschel-Bulkley flow model (HB model), is developed taking into account the effects of minor losses (called HBM model). The HB model parameters are determined by rheological experiments with a commercial shear rheometer. Then, continuity equation and governing differential equation of the HVLP MRF in radial flow are established. Based on the HB model, the expressions of radial velocity distribution are deduced. The influences of minor losses on pressure drop are analyzed with mean fluid velocities. Further, mechanical behavior of the corrugated tube is investigated via drop test. In order to verify the theoretical methodology, a MREA is fabricated and tested using a high-speed drop tower facility with a 600 kg mass at different drop heights and in various magnetic fields. The experiment results show that the HBM model is capable of well predicting the impact behavior of the proposed MREA.

  20. ION KINETIC ENERGY CONSERVATION AND MAGNETIC FIELD STRENGTH CONSTANCY IN MULTI-FLUID SOLAR WIND ALFVÉNIC TURBULENCE

    Energy Technology Data Exchange (ETDEWEB)

    Matteini, L.; Horbury, T. S.; Schwartz, S. J. [The Blackett Laboratory, Imperial College London, SW7 2AZ (United Kingdom); Pantellini, F. [LESIA, Observatoire de Paris, CNRS, UPMC, Universit Paris-Diderot, 5 Place Jules Janssen, F-92195 Meudon (France); Velli, M. [Department of Earth, Planetary, and Space Sciences, UCLA, California (United States)

    2015-03-20

    We investigate the properties of plasma fluid motion in the large-amplitude, low-frequency fluctuations of highly Alfvénic fast solar wind. We show that protons locally conserve total kinetic energy when observed from an effective frame of reference comoving with the fluctuations. For typical properties of the fast wind, this frame can be reasonably identified by alpha particles which, due to their drift with respect to protons at about the Alfvén speed along the magnetic field, do not partake in the fluid low-frequency fluctuations. Using their velocity to transform the proton velocity into the frame of Alfvénic turbulence, we demonstrate that the resulting plasma motion is characterized by a constant absolute value of the velocity, zero electric fields, and aligned velocity and magnetic field vectors as expected for unidirectional Alfvénic fluctuations in equilibrium. We propose that this constraint, via the correlation between velocity and magnetic field in Alfvénic turbulence, is the origin of the observed constancy of the magnetic field; while the constant velocity corresponding to constant energy can only be observed in the frame of the fluctuations, the corresponding constant total magnetic field, invariant for Galilean transformations, remains the observational signature in the spacecraft frame of the constant total energy in the Alfvén turbulence frame.

  1. Mill performance of coal blends

    Energy Technology Data Exchange (ETDEWEB)

    P.A. Bennett; G. O' Brien; D. Holcombe [CoalTech Pty Ltd. (Australia)

    2005-07-01

    Evaluating the potential performance of coal blends for use as pulverised fuel (PF) in power plants and pulverised coal injection (PCI) into blast furnaces requires knowledge of the size distribution of the organic and mineral matter components of a blend, especially when there are significant differences in the Hardgrove Grindability Index (HGI) of the component coals. The size distribution of the organic matter impacts on combustibility of thermal and PCI coal blends and handleability of PCI coal blends. Petrography techniques were used to examine four size fractions from the PF of single coals and blends to measure the size distribution of maceral groups. For most coals, a good estimate of a blend's size distribution can be made assuming that the size distribution of the individual coals, milled under the same conditions, are added together in the proportions of the blend. The exception is when a very soft coal (HGI 90) is blended with a very hard coal (HGI 35). In this case preferential milling (more reporting to the smaller size fractions) of the softer coal occurred. All coals studied in this project show some sign of preferential grinding of the softer maceral group when the coal was milled individually or in a blend. It is only when there is a large difference in the relative strength of the maceral groups of the coals blended that the preferential milling of a coal in a blend is observed in the size distribution of the blend. The results indicate that the breakage characteristics (change in size reduction per unit of energy) of maceral groups in individual coals do not change when they are blended with other coals. 12 refs., 5 figs., 2 tabs.

  2. Fault Detection in Coal Mills used in Power Plants

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Mataji, Babak

    2006-01-01

    In order to achieve high performance and efficiency of coal-fired power plants, it is highly important to control the coal flow into the furnace in the power plant. This means suppression of disturbances and force the coal mill to deliver the required coal flow, as well as monitor the coal mill...... in order to detect faults in the coal mill when they emerge. This paper deals with the second objective. Based on a simple dynamic model of the energy balance a residual is formed for the coal mill. An optimal unknown input observer is designed to estimate this residual. The estimated residual is following...... tested on measured data of a fault in a coal mill, it can hereby be concluded that this residual is very useful for detecting faults in the coal mill....

  3. Structural and magnetic properties of ball milled copper ferrite

    DEFF Research Database (Denmark)

    Goya, G.F.; Rechenberg, H.R.; Jiang, Jianzhong

    1998-01-01

    The structural and magnetic evolution in copper ferrite (CuFe2O4) caused by high-energy ball milling are investigated by x-ray diffraction, Mössbauer spectroscopy, and magnetization measurements. Initially, the milling process reduces the average grain size of CuFe2O4 to about 6 nm and induces ca...

  4. Compressible fluids driven by stochastic forcing: The relative energy inequality and applications

    Czech Academy of Sciences Publication Activity Database

    Breit, D.; Feireisl, Eduard; Hofmanová, M.

    2017-01-01

    Roč. 350, č. 2 (2017), s. 443-473 ISSN 0010-3616 EU Projects: European Commission(XE) 320078 - MATHEF Institutional support: RVO:67985840 Keywords : compressible fluids * Navier-Stokes system Subject RIV: BA - General Mathematics OBOR OECD: Pure mathematics Impact factor: 2.500, year: 2016 http://link.springer.com/article/10.1007%2Fs00220-017-2833-x

  5. Compressible fluids driven by stochastic forcing: The relative energy inequality and applications

    Czech Academy of Sciences Publication Activity Database

    Breit, D.; Feireisl, Eduard; Hofmanová, M.

    2017-01-01

    Roč. 350, č. 2 (2017), s. 443-473 ISSN 0010-3616 EU Projects: European Commission(XE) 320078 - MATHEF Institutional support: RVO:67985840 Keywords : compressible fluids * Navier - Stokes system Subject RIV: BA - General Mathematics OBOR OECD: Pure mathematics Impact factor: 2.500, year: 2016 http://link.springer.com/article/10.1007%2Fs00220-017-2833-x

  6. Synthesis of (Mg0.476Mn0.448Zn0.007)(Fe1.997Ti0.002)O4 powder and sintered ferrites by high energy ball-milling process

    International Nuclear Information System (INIS)

    Shi, X.L.; Yang, H.; Shao, G.Q.; Duan, X.L.; Xiong, Z.; Sun, P.; Wang, T.G.

    2007-01-01

    (Mg 0.476 Mn 0.448 Zn 0.007 )(Fe 1.997 Ti 0.002 )O 4 nanocrystalline powder prepared by high energy ball-milling process were consolidated by microwave and conventional sintering processes. Phases, microstructure and magnetic properties of the ferrites prepared by different processes were investigated. The (Mg 0.476 Mn 0.448 Zn 0.007 )(Fe 1.997 Ti 0.002 )O 4 nanocrystalline powder could be prepared by high energy ball-milling process of raw Fe 3 O 4 , MnO 2 , ZnO, TiO 2 and MgO powders. Prefired and microwave sintered ferrites could achieve the maximum density (4.86 g/cm -3 ), the average grain size (15 μm) was larger than that (10 μm) prepared by prefired and conventionally sintered ferrites with pure ferrite phase, and the saturation magnetization (66.77 emu/g) was lower than that of prefired and conventionally sintered ferrites (88.25 emu/g), the remanent magnetization (0.7367 emu/g) was higher than that of prefired and conventionally sintered ferrites (0.0731 emu/g). Although the microwave sintering process could increase the density of ferrites, the saturation magnetization of ferrites was decreased and the remanent magnetization of ferrites was also increased

  7. Energy transfer between a nanosystem and its host fluid: A multiscale factorization approach

    International Nuclear Information System (INIS)

    Sereda, Yuriy V.; Espinosa-Duran, John M.; Ortoleva, Peter J.

    2014-01-01

    Energy transfer between a macromolecule or supramolecular assembly and a host medium is considered from the perspective of Newton's equations and Lie-Trotter factorization. The development starts by demonstrating that the energy of the molecule evolves slowly relative to the time scale of atomic collisions-vibrations. The energy is envisioned to be a coarse-grained variable that coevolves with the rapidly fluctuating atomistic degrees of freedom. Lie-Trotter factorization is shown to be a natural framework for expressing this coevolution. A mathematical formalism and workflow for efficient multiscale simulation of energy transfer is presented. Lactoferrin and human papilloma virus capsid-like structure are used for validation

  8. Evaluation of absorbents for an absorption heat pump using natural organic working fluids (eco-energy city project)

    Energy Technology Data Exchange (ETDEWEB)

    Hisajima, Daisuke; Sakiyama, Ryoko; Nishiguchi, Akira [Hitachi Ltd., Tsuchiura (Japan). Mechanical Engineering Research Lab.

    1999-07-01

    The present situation of electric power supply and energy consumption in Japan has made it necessary to develop a new absorption air conditioning system which has low electric energy consumption, uses natural organic refrigerants, and can work as a heat pump in winter. Estimating vapor and liquid equilibrium of new pairs of working fluids is prerequisite to developing the new absorption heat pump system. In this phase of the work, methods for estimating vapor and liquid equilibrium that take into account intermolecular force were investigated. Experimental and calculated data on natural organic materials mixtures were considered to find optimum candidates, and then a procedure for evaluation was chosen. Several candidate absorbents were selected that used isobutane and dimethyl ether as refrigerants. (orig.)

  9. Comminution-amorphisation relationships during ball milling of lactose at different milling conditions.

    Science.gov (United States)

    Pazesh, Samaneh; Gråsjö, Johan; Berggren, Jonas; Alderborn, Göran

    2017-08-07

    The purpose of the study was to investigate the relationship between comminution and amorphisation of α-lactose monohydrate particles during ball milling under different milling conditions, including ball-to-powder mass ratio, milling time and ball diameter. The results revealed that at a constant ball filling ratio, ball-to-powder mass ratio of 25:1 resulted in the lowest minimum particle diameter of ∼5μm and the highest degree of apparent amorphous content of 82%. The rate of comminution was high during early stage of milling whereas the degree of apparent amorphous content increased gradually at a slow rate. An increased ball-to-powder mass ratio during milling increased both the rate of comminution and the rate of amorphisation. Using a given ball-to-powder mass ratio, the ball diameter affected the degree of apparent amorphous content of the particles while the particle diameter remained unchanged. The relationship between comminution and amorphisation could be described as consisting of two stages, i.e. comminution dominated and amorphisation dominated stage. It was proposed that the rate constant of comminution and amorphisation are controlled by stress energy distribution in the milling jar and the stress energy distribution is regulated by the ball motion pattern that can be affected by the process parameter used. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  10. Interacting cosmic fluids and phase transitions under a holographic modeling for dark energy

    Energy Technology Data Exchange (ETDEWEB)

    Lepe, Samuel [Pontificia Universidad Catolica de Valparaiso, Instituto de Fisica, Facultad de Ciencias, Valparaiso (Chile); Pena, Francisco [Universidad de La Frontera, Departamento de Ciencias Fisicas, Facultad de Ingenieria y Ciencias, Temuco (Chile)

    2016-09-15

    We discuss the consequences of possible sign changes of the Q-function which measures the transfer of energy between dark energy and dark matter. We investigate this scenario from a holographic perspective by modeling dark energy by a linear parametrization and CPL-parametrization of the equation of state (ω). By imposing the strong constraint of the second law of thermodynamics, we show that the change of sign for Q, due to the cosmic evolution, imply changes in the temperatures of dark energy and dark matter. We also discuss the phase transitions, in the past and future, experienced by dark energy and dark matter (or, equivalently, the sign changes of their heat capacities). (orig.)

  11. Interacting cosmic fluids and phase transitions under a holographic modeling for dark energy

    International Nuclear Information System (INIS)

    Lepe, Samuel; Pena, Francisco

    2016-01-01

    We discuss the consequences of possible sign changes of the Q-function which measures the transfer of energy between dark energy and dark matter. We investigate this scenario from a holographic perspective by modeling dark energy by a linear parametrization and CPL-parametrization of the equation of state (ω). By imposing the strong constraint of the second law of thermodynamics, we show that the change of sign for Q, due to the cosmic evolution, imply changes in the temperatures of dark energy and dark matter. We also discuss the phase transitions, in the past and future, experienced by dark energy and dark matter (or, equivalently, the sign changes of their heat capacities). (orig.)

  12. Computational Fluid Dynamics and Visualisation of Coastal Flows in Tidal Channels Supporting Ocean Energy Development

    Directory of Open Access Journals (Sweden)

    Enayatollah Zangiabadi

    2015-06-01

    Full Text Available Flow characteristics in coastal regions are strongly influenced by the topography of the seabed and understanding the fluid dynamics is necessary before installation of tidal stream turbines (TST. In this paper, the bathymetry of a potential TST deployment site is used in the development of the a CFD (Computational Fluid Dynamics model. The steady state k-ϵ and transient Large Eddy Simulation (LES turbulence methods are employed and compared. The simulations are conducted with a fixed representation of the ocean surface, i.e., a rigid lid representation. In the vicinity of Horse Rock a study of the pressure difference shows that the small change in height of the water column is negligible, providing confidence in the simulation results. The stream surface method employed to visualise the results has important inherent characteristics that can enhance the visual perception of complex flow structures. The results of all cases are compared with the flow data transect gathered by an Acoustic Doppler Current Profiler (ADCP. It has been understood that the k-ϵ method can predict the flow pattern relatively well near the main features of the domain and the LES model has the ability to simulate some important flow patterns caused by the bathymetry.

  13. A Solar Chimney for renewable energy production: thermo-fluid dynamic optimization by CFD analyses

    Science.gov (United States)

    Montelpare, S.; D'Alessandro, V.; Zoppi, A.; Costanzo, E.

    2017-11-01

    This paper analyzes the performance of a solar tower designed for renewable energy production. The Solar Chimney Power Plant (SCPP) involves technology that converts solar energy by means of three basic components: a large circular solar collector, a high tower in the center of the collector and a turbine generator inside the chimney. SCPPs are characterized by long term operational life, low maintenance costs, zero use of fuels, no use of water and no emissions of greenhouse gases. The main problem of this technology is the low energy global conversion coefficient due to the presence of four conversions: solar radiation > thermal energy > kinetic energy > mechanical energy > electric energy. This paper defines its starting point from the well known power plant of Manzanares in order to calibrate a numerical model based on finite volumes. Following that, a solar tower with reduced dimensions was designed and an analysis on various geometric parameters was conducted: on the inlet section, on the collector slope, and on the fillet radius among the SUPP sections. Once the optimal solution was identified, a curved deflectors able to induce a flow swirl along the vertical tower axis was designed.

  14. Comminution of B4C powders with a high-energy mill operated in air in dry or wet conditions and its effect on their spark-plasma sinterability

    DEFF Research Database (Denmark)

    Ortiz, Angel L.; Sánchez-Bajo, Florentino; Leal, Victor Manuel Candelario

    2017-01-01

    to the nanoscale. While this is accompanied by oxidation and aggregation, these are not serious drawbacks. Wet shaker milling in methanol (i.e., conventional ball-milling) resulted only in a moderate B4C particle refinement with greater contamination by the milling tools, which limits its usefulness. It was also......-plasma sintering confirmed this recommendation, and also showed the usefulness of dry shaker milling to obtain refined B4C microstructures for structural applications....

  15. Discussion of “Nanoscale Fluid Mechanics and Energy Conversion” (Chen, X., Xu, B., and Liu, L., 2014, ASME Appl. Mech. Rev., 66(5), p. 050803)

    NARCIS (Netherlands)

    Eijkel, Jan C.T.

    2014-01-01

    The authors of the paper “Nanoscale Fluid Mechanics and Energy Conversion” have presented an overview of recent applications of nanofluidic phenomena for energy conversion and storage. The discussion given here aims to place this paper in a broader context of literature and theory.

  16. Super- and Transcritical Fluid Expansions for Next-Generation Energy Conversion Systems

    NARCIS (Netherlands)

    Harinck, J.

    2010-01-01

    The next generation of thermodynamic power cycles offers great potential as the conceptual basis for sustainable energy converters. Examples are the supercritical and superheated Organic Rankine cycle, the transcritical condensation cycle, the supercritical Brayton cycle, the Organic Stirling cycle

  17. Energy transfer between a nanosystem and its host fluid: A multiscale factorization approach

    Energy Technology Data Exchange (ETDEWEB)

    Sereda, Yuriy V.; Espinosa-Duran, John M.; Ortoleva, Peter J., E-mail: ortoleva@indiana.edu [Center for Cell and Virus Theory, Department of Chemistry, Indiana University, 800 E. Kirkwood Ave, Bloomington, Indiana 47405 (United States)

    2014-02-21

    Energy transfer between a macromolecule or supramolecular assembly and a host medium is considered from the perspective of Newton's equations and Lie-Trotter factorization. The development starts by demonstrating that the energy of the molecule evolves slowly relative to the time scale of atomic collisions-vibrations. The energy is envisioned to be a coarse-grained variable that coevolves with the rapidly fluctuating atomistic degrees of freedom. Lie-Trotter factorization is shown to be a natural framework for expressing this coevolution. A mathematical formalism and workflow for efficient multiscale simulation of energy transfer is presented. Lactoferrin and human papilloma virus capsid-like structure are used for validation.

  18. Energy Harvesting from Fluid Flow in Water Pipelines for Smart Metering Applications

    International Nuclear Information System (INIS)

    Hoffmann, D; Willmann, A; Göpfert, R; Becker, P; Folkmer, B; Manoli, Y

    2013-01-01

    In this paper a rotational, radial-flux energy harvester incorporating a three-phase generation principle is presented for converting energy from water flow in domestic water pipelines. The energy harvester together with a power management circuit and energy storage is used to power a smart metering system installed underground making it independent from external power supplies or depleting batteries. The design of the radial-flux energy harvester is adapted to the housing of a conventional mechanical water flow meter enabling the use of standard components such as housing and impeller. The energy harvester is able to generate up to 720 mW when using a flow rate of 20 l/min (fully opened water tab). A minimum flow rate of 3 l/min is required to get the harvester started. In this case a power output of 2 mW is achievable. By further design optimization of the mechanical structure including the impeller and magnetic circuit the threshold flow rate can be further reduced

  19. Energy Harvesting from Fluid Flow in Water Pipelines for Smart Metering Applications

    Science.gov (United States)

    Hoffmann, D.; Willmann, A.; Göpfert, R.; Becker, P.; Folkmer, B.; Manoli, Y.

    2013-12-01

    In this paper a rotational, radial-flux energy harvester incorporating a three-phase generation principle is presented for converting energy from water flow in domestic water pipelines. The energy harvester together with a power management circuit and energy storage is used to power a smart metering system installed underground making it independent from external power supplies or depleting batteries. The design of the radial-flux energy harvester is adapted to the housing of a conventional mechanical water flow meter enabling the use of standard components such as housing and impeller. The energy harvester is able to generate up to 720 mW when using a flow rate of 20 l/min (fully opened water tab). A minimum flow rate of 3 l/min is required to get the harvester started. In this case a power output of 2 mW is achievable. By further design optimization of the mechanical structure including the impeller and magnetic circuit the threshold flow rate can be further reduced.

  20. Developing Computational Fluid Dynamics (CFD Models to Evaluate Available Energy in Exhaust Systems of Diesel Light-Duty Vehicles

    Directory of Open Access Journals (Sweden)

    Pablo Fernández-Yáñez

    2017-06-01

    Full Text Available Around a third of the energy input in an automotive engine is wasted through the exhaust system. Since numerous technologies to harvest energy from exhaust gases are accessible, it is of great interest to find time- and cost-efficient methods to evaluate available thermal energy under different engine conditions. Computational fluid dynamics (CFD is becoming a very valuable tool for numerical predictions of exhaust flows. In this work, a methodology to build a simple three-dimensional (3D model of the exhaust system of automotive internal combustion engines (ICE was developed. Experimental data of exhaust gas in the most used part of the engine map in passenger diesel vehicles were employed as input for calculations. Sensitivity analyses of different numeric schemes have been conducted in order to attain accurate results. The model built allows for obtaining details on temperature and pressure fields along the exhaust system, and for complementing the experimental results for a better understanding of the flow phenomena and heat transfer through the system for further energy recovery devices.

  1. Hybrid Fluid/Kinetic Modeling Of Magnetized High Energy Density Plasmas

    Science.gov (United States)

    Hansen, David; Held, Eric; King, Jacob; Stoltz, Peter; Masti, Robert; Srinivasan, Bhuvana

    2017-10-01

    MHD modeling with an equation of state (EOS) of the Rayleigh-Taylor (RT) instabily in Z indicates that it is seeded by the electro-thermal instability. Large thermodynamic drives associated with gradients at the interface between the liner and the coronal regions distort distribution functions and likely lead to non-local transport effects in a plasma which varies from weakly to strongly coupled. In this work, we discuss using effective potential theory along with a Chapman-Ensksog-like (CEL) formalism to develop hybrid fluid/kinetic modeling capabilities for these plasmas. Effective potential theory addresses the role of Coulomb collisions on transport across coupling regimes and the CEL approach bridges the gap between full-blow kinetic simulations and the EOS tables, which only depend locally on density and temperature. Quantitative results on the Spitzer problem across coupling coupling regimes will be presented as a first step. DOE Grant No. DE-SC0016525.

  2. On/off multi-poppet valve for switching manifold in discrete fluid power force system PTO in wave energy converters

    DEFF Research Database (Denmark)

    Hansen, Anders Hedegaard; Pedersen, Henrik C.; Andersen, Torben Ole

    2014-01-01

    less than 10 ms. The pilot stage is directly actuated and utilises internal valve pressure as supply and an external tank connection as drain. The current paper presents the multi-disciplinary design process leading to the final valve design. This includes the geometric design of the main stage......Fluid power systems are the leading technology for power take off systems in ocean wave energy converters. However, fluid power systems often suffer from poor efficiency, especially in part loads. This degrades the PTO system efficiency and therefore lowers the energy production. To overcome...... the issues with poor system efficiency, a discrete fluid power system is proposed as a main part of the PTO system. For the discrete system to be feasible large fluid power switching valves are needed. The current paper presents a two stage 1,000 L/min@5 bar multi-poppet on-off valve with a switching time...

  3. Higher derivative super Yang-Mills theories

    International Nuclear Information System (INIS)

    Bergshoeff, E.; Rakowski, M.; Sezgin, E.

    1986-11-01

    The most general higher derivative Yang-Mills actions of the type (F 2 +α2F 4 ) which are globally supersymmetric up to order α 2 in six and ten dimensional spacetimes are given. The F 4 -terms turn out to occur in the combination α 2 (tr F 4 - 1/4(tr F 2 ) 2 ), where the trace is over the Lorentz indices. This result agrees with the low energy limit of the open superstring in ten dimensions, where α is the string tension. Surprisingly, the transformation rules of the Yang-Mills multiplet receive order α 2 corrections even in the off-shell formulation. For the case of Abelian Yang-Mills group, the action is expressed in Born-Infeld form with a metric generically given by (1+α 2 F 2 +...). (author)

  4. Interactive mixture of inhomogeneous dark fluids driven by dark energy: a dynamical system analysis

    Science.gov (United States)

    Izquierdo, Germán; Blanquet-Jaramillo, Roberto C.; Sussman, Roberto A.

    2018-03-01

    We examine the evolution of an inhomogeneous mixture of non-relativistic pressureless cold dark matter (CDM), coupled to dark energy (DE) characterised by the equation of state parameter wspace evolution around the critical points (past/future attractors and five saddles) is examined in detail. For all parameter values and both directions of energy flow (CDM to DE and DE to CDM) the phase space trajectories are compatible with a physically plausible early cosmic times behaviour near the past attractor. This result compares favourably with mixtures with interaction driven by the CDM density, whose past evolution is unphysical for DE to CDM energy flow. Numerical examples are provided describing the evolution of an initial profile that can be associated with idealised structure formation scenarios.

  5. Augmenting convection-enhanced delivery through simultaneous co-delivery of fluids and laser energy with a fiberoptic microneedle device

    Science.gov (United States)

    Hood, R. Lyle; Ecker, Tobias; Andriani, Rudy; Robertson, John; Rossmeisl, John; Rylander, Christopher G.

    2013-03-01

    This paper describes a new infusion catheter, based on our fiberoptic microneedle device (FMD), designed with the objective of photothermally augmenting the volumetric dispersal of infused therapeutics. We hypothesize that concurrent delivery of laser energy, causing mild localized photothermal heating (4-5 °C), will increase the spatial dispersal of infused chemotherapy over a long infusion period. Agarose brain phantoms, which mimic the brain's mechanical and fluid conduction properties, were constructed from 0.6 wt% Agarose in aqueous solution. FMDs were fabricated by adhering a multimode fiberoptic to a silica capillary tube, such that their flat-polished tips co-terminated. Continuous wave 1064 nm light was delivered simultaneously with FD&C Blue #2 (5%) dye into phantoms. Preliminary experiments, where co-delivery was tested against fluid delivery alone (through symmetrical infusions into in vivo rodent models), were also conducted. In the Agarose phantoms, volumetric dispersal was demonstrated to increase by more than 3-fold over a four-hour infusion time frame for co-delivery relative to infusion-only controls. Both forward and backward (reflux) infusions were also observed to increase slightly. Increased volumetric dispersal was demonstrated with co-delivery in an in vivo rodent model. Photothermal augmentation of infusion was demonstrated to influence the directionality and increase the volume of dye dispersal in Agarose brain phantoms. With further development, FMDs may enable a greater distribution of chemotherapeutic agents during CED therapy of brain tumors.

  6. Local shell-to-shell energy transfer via nonlocal interactions in fluid ...

    Indian Academy of Sciences (India)

    The computation has been done using first-order perturbative field theory. In three dimensions, magnitude of triad interactions is large for nonlocal triads, and small for local triads. However, the shell-to-shell energy transfer rate is found to be local and forward. This result is due to the fact that the nonlocal triads occupy much ...

  7. Application study of fluid pressure energy recycling of decarbonisation process by C4H6O3 in ammonia synthesis systems by hydraulic turbochargers

    Science.gov (United States)

    Ji, Yunguang; Xu, Yangyang; Li, Hongtao; Oklejas, Michael; Xue, Shuqi

    2018-01-01

    A new type of hydraulic turbocharger energy recovery system was designed and applied in the decarbonisation process by propylene carbonate of a 100k tons ammonia synthesis system firstly in China. Compared with existing energy recovery devices, hydraulic turbocharger energy recovery system runs more smoothly, has lower failure rate, longer service life and greater comprehensive benefits due to its unique structure, simpler adjustment process and better adaptability to fluid fluctuation.

  8. Loop groups and Yang-Mills theory in dimension two

    DEFF Research Database (Denmark)

    Gravesen, Jens

    1990-01-01

    -Mills function of ω is the sum of the energy of γ and the square of a certain norm of f. In particular, the Yang-Mills functional has the same Morse theory as the energy functional on ΩG. There is a similar description of connections in a G-bundle over an arbitrary Riemann surface, but so far not of the Yang...

  9. Uranium mining and milling

    International Nuclear Information System (INIS)

    Floeter, W.

    1976-01-01

    In this report uranium mining and milling are reviewed. The fuel cycle, different types of uranium geological deposits, blending of ores, open cast and underground mining, the mining cost and radiation protection in mines are treated in the first part of this report. In the second part, the milling of uranium ores is treated, including process technology, acid and alkaline leaching, process design for physical and chemical treatment of the ores, and the cost. Each chapter is clarified by added figures, diagrams, tables, and flowsheets. (HK) [de

  10. Aspects of the use of saturated fluorocarbon fluids in high energy physics

    Energy Technology Data Exchange (ETDEWEB)

    Hallewell, G., E-mail: Gregory.Hallewell@cern.c [Centre de Physique des Particules de Marseille, 163 Avenue de Luminy, Case 907, 13288 Marseille Cedex 09 (France)

    2011-05-21

    The excellent dielectric properties of saturated fluorocarbons have allowed their use in direct immersion liquid cooling of electronics, including supercomputers and as heat transfer media in vapour phase soldering and burn-in testing of electronics. Their high density, UV transparency, non-flammability, non-toxicity and radiation tolerance have led to their use as liquid and gas radiator media for RICH detectors in numerous particle physics experiments. Systems to circulate and purify saturated fluorocarbon Cherenkov radiator vapours often rely on thermodynamic evaporation-condensation cycles similar to those used in refrigeration. Their use as evaporative refrigerants was pioneered for the ATLAS silicon tracker, and they are now also used as evaporative coolants in ALICE and TOTEM and as liquid coolants in ATLAS and CMS. Ultrasonic techniques for vapour phase analysis of fluorocarbon mixtures-developed for the SLAC SLD barrel CRID radiator during the 1980s as an alternative to UV refractometry are again under development for the ATLAS tracker evaporative cooling system. Examples of fluorocarbon circulation systems, together with purification and analysis techniques for these versatile fluids are mentioned.

  11. Enhancing Understanding of Magnetized High Energy Density Plasmas from Solid Liner Implosions Using Fluid Modeling with Kinetic Closures

    Science.gov (United States)

    Masti, Robert; Srinivasan, Bhuvana; King, Jacob; Stoltz, Peter; Hansen, David; Held, Eric

    2017-10-01

    Recent results from experiments and simulations of magnetically driven pulsed power liners have explored the role of early-time electrothermal instability in the evolution of the MRT (magneto-Rayleigh-Taylor) instability. Understanding the development of these instabilities can lead to potential stabilization mechanisms; thereby providing a significant role in the success of fusion concepts such as MagLIF (Magnetized Liner Inertial Fusion). For MagLIF the MRT instability is the most detrimental instability toward achieving fusion energy production. Experiments of high-energy density plasmas from wire-array implosions have shown the requirement for more advanced physics modeling than that of ideal magnetohydrodynamics. The overall focus of this project is on using a multi-fluid extended-MHD model with kinetic closures for thermal conductivity, resistivity, and viscosity. The extended-MHD model has been updated to include the SESAME equation-of-state tables and numerical benchmarks with this implementation will be presented. Simulations of MRT growth and evolution for MagLIF-relevant parameters will be presented using this extended-MHD model with the SESAME equation-of-state tables. This work is supported by the Department of Energy Office of Science under Grant Number DE-SC0016515.

  12. Interaction of Gravitational field and Brans-Dicke field in R/W universe containing Dark Energy like fluid

    International Nuclear Information System (INIS)

    Singh, Kangujam Priyokumar; Dewri, Mukunda; Singh, Koijam Manihar

    2016-01-01

    On studying some new models of Robertson-Walker universes with a Brans-Dicke scalar field, it is found that most of these universes contain a dark energy like fluid which confirms the present scenario of the expansion of the universe. In one of the cases, the exact solution of the field equations gives a universe with a false vacuum, while in another it reduces to that of dust distribution in the Brans-Dicke cosmology when the cosmological constant is not in the picture. In one particular model it is found that the universe may undergo a Big Rip in the future, and thus it will be very interesting to investigate such models further. (paper)

  13. Design of Bidirectional Check Valve for Discrete Fluid Power Force System for Wave Energy Converters

    DEFF Research Database (Denmark)

    Hansen, Anders Hedegaard; Pedersen, Henrik C.; Andersen, Torben Ole

    2014-01-01

    introduces large switching losses, especially when large pressure difference is present across the valves in the manifold. The current paper therefore focus on designing a bidirectional check valve for use in the switching manifold of the discrete force systems. The use of the bidirectional check valve...... enables passive force switching under minimal pressure difference, hence minimal energy loss. The bidirectional check valve is designed with a rated flow in the range of 1000L/min@5bar. The flow direction of the bidirectional check valve is set by the setting the pilot pressure. This paper presents...... a functionality test of a 125 L/min@5bar bidirectional check, leading to the design and modelling of a bidirectional check valve for ocean wave energy. It shows that a feasible bidirectional check valve may be configured by employing a multi-poppet topology for the main stage and utilising a 3/2 switching valve...

  14. Combinatorial Optimization for Energy Saving in Nickel Industry Non-Newtonian Fluid Pumping System

    International Nuclear Information System (INIS)

    Hernández Ramírez, Gabriel; Legra Lobaina, Aristides; Columbié Navarro, Angel; Marcos Aníbal León Segovia

    2017-01-01

    In the present work a study of the influence of the rheological parameters of the lateritic hydromixtures with the energetic ones of the pumping systems that guarantee the productivity of nickel company 'Commander Pedro Sotto Alba' is carried out. From an experimental study and through an estimator, the rheological parameters are modeled as a function of the factors: temperature, solids content, chemical and granulometric composition. From an appropriate discretization of the model of the lateritic hydrometer pumping system and the application of a Discrete Combination Optimization Double Sequencing procedure, the operating parameters of this system were obtained, in order to guarantee a flow rate of 1600 m3 / h and one Adequate solids concentration. It is concluded that the use of a mathematical model that relates the rheological parameters of the lateritic pulp and the energy parameters of the pumping system, guarantee the metallurgical and energy efficiency in the acid leaching process with an average increase in production between 1000-1500 T Ni + Co / y and an energy saving of 30 MWh /year. (author)

  15. Coexistence of short- and long-range ferromagnetic order in nanocrystalline Fe2Mn1−xCuxAl (x=0.0, 0.1 and 0.3) synthesized by high-energy ball milling

    International Nuclear Information System (INIS)

    Thanh, Tran Dang; Nanto, Dwi; Tuyen, Ngo Thi Uyen; Nan, Wen-Zhe; Yu, YiKyung; Tartakovsky, Daniel M.; Yu, S.C.

    2015-01-01

    In this work, we prepared nanocrystalline Fe 2 Mn 1−x Cu x Al (x=0.0, 0.1 and 0.3) powders by the high energy ball milling technique, and then studied their critical properties. Our analysis reveals that the increase of Cu-doping concentration (up to x=0.3) in these powders leads to a gradual increase of the ferromagnetic–paramagnetic transition temperature from 406 to 452 K. The Banerjee criterion suggests that all the samples considered undergo a second-order phase transition. A modified Arrott plot and scaling analysis indicate that the critical exponents (β=0.419 and 0.442, γ=1.082 and 1.116 for x=0.0 and 0.1, respectively) are located in between those expected for the 3D-Heisenberg and the mean-field models; the values of β=0.495 and γ=1.046 for x=0.3 sample are very close to those of the mean-field model. These features reveal the coexistence of the short- and long-range ferromagnetic order in the nanocrystalline Fe 2 Mn 1−x Cu x Al powders. Particularly, as the concentration of Cu increases, values of the critical exponent shift towards those of the mean-field model. Such results prove the Cu doping favors establishing a long-range ferromagnetic order. - Highlights: • Fe 2 Mn 1−x Cu x Al nanocrystals were prepared by a high energy ball milling method. • A coexistence of the short- and long-range FM order in the nanocrystals. • Cu doping favors establishing a long-range FM order in the nanocrystals. • All the ΔS m (T, H) data are followed a universal master curve

  16. Solid-state vitrification of crystalline griseofulvin by mechanical milling.

    Science.gov (United States)

    Willart, Jean-François; Carpentier, Laurent; Danède, Florence; Descamps, Marc

    2012-04-01

    The thermodynamic, dynamic, and structural changes of crystalline griseofulvin upon high-energy ball milling at room temperature have been studied. The investigations have been performed by differential scanning calorimetry (DSC), dielectric relaxation spectroscopy, and powder X-ray diffraction. The results indicate that this compound undergoes a direct crystal-to-glass transformation upon milling, whereas no glass transition can be clearly detected upon heating because of the exceptional sub-glass transition temperature (T(g) ) recrystallization of the milled sample. This intrinsic difficulty for characterizing the glassy state has been overcome using three independent strategies: (i) comparison of the evolutions upon milling of both the crystalline powder and the quenched liquid, (ii) use of fast DSC to delay the recrystallization event, and (iii) search for dielectric β relaxations typical of glasses in the milled compound. Copyright © 2012 Wiley Periodicals, Inc.

  17. Effect of External Pressure and Catheter Gauge on Flow Rate, Kinetic Energy, and Endothelial Injury During Intravenous Fluid Administration in a Rabbit Model.

    Science.gov (United States)

    Hu, Mei-Hua; Chan, Wei-Hung; Chen, Yao-Chang; Cherng, Chen-Hwan; Lin, Chih-Kung; Tsai, Chien-Sung; Chou, Yu-Ching; Huang, Go-Shine

    2016-01-01

    The effects of intravenous (IV) catheter gauge and pressurization of IV fluid (IVF) bags on fluid flow rate have been studied. However, the pressure needed to achieve a flow rate equivalent to that of a 16 gauge (G) catheter through smaller G catheters and the potential for endothelial damage from the increased kinetic energy produced by higher pressurization are unclear. Constant pressure on an IVF bag was maintained by an automatic adjustable pneumatic pressure regulator of our own design. Fluids running through 16 G, 18 G, 20 G, and 22 G catheters were assessed while using IV bag pressurization to achieve the flow rate equivalent to that of a 16 G catheter. We assessed flow rates, kinetic energy, and flow injury to rabbit inferior vena cava endothelium. By applying sufficient external constant pressure to an IVF bag, all fluids could be run through smaller (G) catheters at the flow rate in a 16 G catheter. However, the kinetic energy increased significantly as the catheter G increased. Damage to the venous endothelium was negligible or minimal/patchy cell loss. We designed a new rapid infusion system, which provides a constant pressure that compresses the fluid volume until it is free from visible residual fluid. When large-bore venous access cannot be obtained, multiple smaller catheters, external pressure, or both should be considered. However, caution should be exercised when fluid pressurized to reach a flow rate equivalent to that in a 16 G catheter is run through a smaller G catheter because of the profound increase in kinetic energy that can lead to venous endothelium injury.

  18. Computer simulation of energy use, greenhouse gas emissions, and costs for alternative methods of processing fluid milk.

    Science.gov (United States)

    Tomasula, P M; Datta, N; Yee, W C F; McAloon, A J; Nutter, D W; Sampedro, F; Bonnaillie, L M

    2014-07-01

    Computer simulation is a useful tool for benchmarking electrical and fuel energy consumption and water use in a fluid milk plant. In this study, a computer simulation model of the fluid milk process based on high temperature, short time (HTST) pasteurization was extended to include models for processes for shelf-stable milk and extended shelf-life milk that may help prevent the loss or waste of milk that leads to increases in the greenhouse gas (GHG) emissions for fluid milk. The models were for UHT processing, crossflow microfiltration (MF) without HTST pasteurization, crossflow MF followed by HTST pasteurization (MF/HTST), crossflow MF/HTST with partial homogenization, and pulsed electric field (PEF) processing, and were incorporated into the existing model for the fluid milk process. Simulation trials were conducted assuming a production rate for the plants of 113.6 million liters of milk per year to produce only whole milk (3.25%) and 40% cream. Results showed that GHG emissions in the form of process-related CO₂ emissions, defined as CO₂ equivalents (e)/kg of raw milk processed (RMP), and specific energy consumptions (SEC) for electricity and natural gas use for the HTST process alone were 37.6g of CO₂e/kg of RMP, 0.14 MJ/kg of RMP, and 0.13 MJ/kg of RMP, respectively. Emissions of CO2 and SEC for electricity and natural gas use were highest for the PEF process, with values of 99.1g of CO₂e/kg of RMP, 0.44 MJ/kg of RMP, and 0.10 MJ/kg of RMP, respectively, and lowest for the UHT process at 31.4 g of CO₂e/kg of RMP, 0.10 MJ/kg of RMP, and 0.17 MJ/kg of RMP. Estimated unit production costs associated with the various processes were lowest for the HTST process and MF/HTST with partial homogenization at $0.507/L and highest for the UHT process at $0.60/L. The increase in shelf life associated with the UHT and MF processes may eliminate some of the supply chain product and consumer losses and waste of milk and compensate for the small increases in GHG

  19. Similarity Laws for the Lines of Ideal Free Energy and Chemical Potential in Supercritical Fluids.

    Science.gov (United States)

    Apfelbaum, E M; Vorob'ev, V S

    2017-09-21

    We have found the curves on the density-temperature plane, along which the values of free energy and chemical potential correspond to ideal gas quantities. At first, we have applied the van der Waals equation to construct them and to derive their equations. Then we have shown that the same lines for real substances (Ar, N 2 , CH 4 , SF 6 , H 2 , H 2 O) and for the model Lennard-Jones system constructed on the basis of the measurements data and calculations are well matched with the derived equations. The validity and deviations from the obtained similarity laws are discussed.

  20. Coefficient of energy balance, a new parameter for basic investigation of the cerebrospinal fluid

    Czech Academy of Sciences Publication Activity Database

    Kelbich, P.; Hejčl, Aleš; Krulichova, S. I.; Procházka, J.; Hanuljaková, E.; Peruthová, J.; Koudelková, M.; Sameš, M.; Krejsek, J.

    2014-01-01

    Roč. 52, č. 7 (2014), s. 1009-1017 ISSN 1434-6621 R&D Projects: GA MŠk EE2.3.20.0274 Grant - others:GA UK(CZ) P37/09; GA UK(CZ) P37/10; GA MZd(CZ) NT13883; GA MŠk(CZ) Project FNUSA-ICRC CZ.1.05/1.1.00/02.0123 Institutional support: RVO:68378041 Keywords : coefficient of energy balance * CSF compartment * cytological picture of the CSF Subject RIV: FH - Neurology Impact factor: 2.707, year: 2014

  1. Energy Optimal Tracking Control with Discrete Fluid Power Systems using Model Predictive Control

    DEFF Research Database (Denmark)

    Hansen, Anders Hedegaard; Asmussen, Magnus Færing; Bech, Michael Møller

    2017-01-01

    For Discrete Displacement Cylinder (DDC) drives the control task lies in choosing force level. Hence, which force level to apply and thereby which pressure level each cylinder chambers shall be connected to. The DDC system is inherently a force system why often a force reference is generated by a...... and compared to a PID like tracking controller combined with a FSA. The results indicate that the energy efficiency of position tracking DDC systems may be improved significantly by using the MPC algorithm.......For Discrete Displacement Cylinder (DDC) drives the control task lies in choosing force level. Hence, which force level to apply and thereby which pressure level each cylinder chambers shall be connected to. The DDC system is inherently a force system why often a force reference is generated...... by a tracking controller and translated into a discrete force level in a Force Shifting Algorithm (FSA). In the current paper the tracking controller and the FSA are combined in a Model Predictive Control algorithm solving the tracking problem while minimizing the energy use. Two MPC algorithms are investigated...

  2. Releases of radioactivity from uranium mills and effluent treatment costs

    International Nuclear Information System (INIS)

    Witherspoon, J.P.; Sears, M.B.; Blanco, R.E.

    1977-01-01

    Airborne releases of radioactive materials from uranium milling to the environment consist of ore dust, yellowcake dust, tailings dust, and radon gas while the mill is active. After a mill has ceased operations, tailings may be stabilized to minimize or prevent airborne releases of radioactive particulates. However, radon gas will continue to be released in amounts inversely proportional to the degree of stabilization treatment (and expense). Liquid waste disposal is by evaporation and natural seepage to the ground beneath the tailings impoundment area. The release of radioactive materials (and potential radiation exposures) determines the majority of costs associated with minimizing the environmental impact of uranium milling. Radwaste treatments to reduce estimated radiation doses to individuals to 3 to 5% of those received with current milling practices are equivalent to $0.66 per pounds of U 3 O 8 and 0.032 mill per kWhr of electricity. This cost would cover a high efficiency reverse jet bag filter and high energy venturi scrubbers for dusts, neutralization of liquids, and an asphalt-lined tailings basin with a clay core dam to reduce seepage. In addition, this increased cost would cover stabilization of tailings, after mill closure, with a 1-in. asphalt membrane topped by 2 ft of earth and 0.5 ft of crushed rock to provide protection against future leaching and wind erosion. The cost of reducing the radiological hazards associated with uranium milling to this degree would contribute about 0.4% to the current total cost of nuclear power

  3. Controlling the shape of LiCoPO₄ nanocrystals by supercritical fluid process for enhanced energy storage properties.

    Science.gov (United States)

    Truong, Quang Duc; Devaraju, Murukanahally Kempaiah; Ganbe, Yoshiyuki; Tomai, Takaaki; Honma, Itaru

    2014-02-05

    Lithium-ion batteries offer promising opportunities for novel energy storage systems and future application in hybrid electric vehicles or electric vehicles. Cathode materials with high energy density are required for practical application. Herein, high-voltage LiCoPO4 cathode materials with different shapes and well-developed facets such as nanorods and nanoplates with exposed {010} facets have been synthesized by a one-pot supercritical fluid (SCF) processing. The effect of different amines and their roles on the morphology-control has been investigated in detail. It was found that amine having long alkyl chain such as hexamethylenediamine played important roles to manipulate the shape of the nanocrystals by selective adsorption on the specific {010} facets. More importantly, the nanorods and nanoplates showed better electrochemical performance than that of nanoparticles which was attributed to their unique crystallographic orientation with short Li ion diffusion path. The present study emphasizes the importance of crystallographic orientation in improving the electrochemical performance of the high voltage LiCoPO4 cathode materials for Li-ion batteries.

  4. Performance and energy saving analysis of a refrigerator using hydrocarbon mixture (HC-R134a) as working fluid

    Science.gov (United States)

    Mohtar, M. N.; Nasution, H.; Aziz, A. A.

    2015-12-01

    The use of hydrocarbon mixture as a working fluid in a refrigerator system is rarely explored. Almost all domestic refrigerators use hydroflourocarbon R134a (HFC-R134a) as refrigerants. In this study, hydrocarbon gas (HC-R134a) is used as the alternative refrigerant to replace HFC-R134a. It has a composition of R290 (56%), R600a (54.39%) and additive (0.1%wt) blended for the trials. The experiments were conducted with 105 g and 52.5 g refrigerant mass charge, subjected to internal heat load of 0, 1, 2, 3 and 4 kg respectively. The study investigates the coefficient of performance of the refrigerator (COPR) and energy consumption. The results show that the use of HC-R134a as the replaceable refrigerant can save energy ranging from 2.04% to 7.09%, as compared to the conventional HFC-R134a refrigerant. Naturally, the COPR improvement and temperature distribution using HC-R134a are much better than HFC-R134a

  5. Energy variational analysis of ions in water and channels: Field theory for primitive models of complex ionic fluids.

    Science.gov (United States)

    Eisenberg, Bob; Hyon, Yunkyong; Liu, Chun

    2010-09-14

    component is added to the energy or dissipation, the Euler-Lagrange equations change form and interaction terms appear without additional adjustable parameters. EnVarA has previously been used to compute properties of liquid crystals, polymer fluids, and electrorheological fluids containing solid balls and charged oil droplets that fission and fuse. Here we apply EnVarA to the primitive model of electrolytes in which ions are spheres in a frictional dielectric. The resulting Euler-Lagrange equations include electrostatics and diffusion and friction. They are a time dependent generalization of the Poisson-Nernst-Planck equations of semiconductors, electrochemistry, and molecular biophysics. They include the finite diameter of ions. The EnVarA treatment is applied to ions next to a charged wall, where layering is observed. Applied to an ion channel, EnVarA calculates a quick transient pile-up of electric charge, transient and steady flow through the channel, stationary "binding" in the channel, and the eventual accumulation of salts in "unstirred layers" near channels. EnVarA treats electrolytes in a unified way as complex rather than simple fluids. Ad hoc descriptions of interactions and flow have been used in many areas of science to deal with the nonideal properties of electrolytes. It seems likely that the variational treatment can simplify, unify, and perhaps derive and improve those descriptions.

  6. Energy variational analysis of ions in water and channels: Field theory for primitive models of complex ionic fluids

    Science.gov (United States)

    Eisenberg, Bob; Hyon, YunKyong; Liu, Chun

    2010-09-01

    component is added to the energy or dissipation, the Euler-Lagrange equations change form and interaction terms appear without additional adjustable parameters. EnVarA has previously been used to compute properties of liquid crystals, polymer fluids, and electrorheological fluids containing solid balls and charged oil droplets that fission and fuse. Here we apply EnVarA to the primitive model of electrolytes in which ions are spheres in a frictional dielectric. The resulting Euler-Lagrange equations include electrostatics and diffusion and friction. They are a time dependent generalization of the Poisson-Nernst-Planck equations of semiconductors, electrochemistry, and molecular biophysics. They include the finite diameter of ions. The EnVarA treatment is applied to ions next to a charged wall, where layering is observed. Applied to an ion channel, EnVarA calculates a quick transient pile-up of electric charge, transient and steady flow through the channel, stationary "binding" in the channel, and the eventual accumulation of salts in "unstirred layers" near channels. EnVarA treats electrolytes in a unified way as complex rather than simple fluids. Ad hoc descriptions of interactions and flow have been used in many areas of science to deal with the nonideal properties of electrolytes. It seems likely that the variational treatment can simplify, unify, and perhaps derive and improve those descriptions.

  7. Elliptic Yang-Mills equation.

    Science.gov (United States)

    Tian, Gang

    2002-11-26

    We discuss some recent progress on the regularity theory of the elliptic Yang-Mills equation. We start with some basic properties of the elliptic Yang-Mills equation, such as Coulomb gauges, monotonicity, and curvature estimates. Next we discuss singularity of stationary Yang-Mills connections and compactness theorems on Yang-Mills connections with bounded L(2) norm of curvature. We also discuss in some detail self-dual solutions of the Yang-Mills equation and describe a compactification of their moduli space.

  8. Elliptic Yang–Mills equation

    OpenAIRE

    Tian, Gang

    2002-01-01

    We discuss some recent progress on the regularity theory of the elliptic Yang–Mills equation. We start with some basic properties of the elliptic Yang–Mills equation, such as Coulomb gauges, monotonicity, and curvature estimates. Next we discuss singularity of stationary Yang–Mills connections and compactness theorems on Yang–Mills connections with bounded L2 norm of curvature. We also discuss in some detail self-dual solutions of the Yang–Mills equation and describe a compactification of the...

  9. The effect of surfactant addition on high-energy milling upon the magnetic properties and microstructure of the Pr-Fe-B HDDR magnetic powders; Efeito da adicao de surfactantes nas propriedades e microestrutura de pos magneticos a base de Pr-Fe-B obtidos via HDDR e moagem de alta energia

    Energy Technology Data Exchange (ETDEWEB)

    Santos, P.B.; Silva, S.C.; Faria, R.N.; Takiishia, H., E-mail: pbsantos@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2010-07-01

    Nanomagnetic powders based on the composition Pr{sub 12}Fe{sub 65.9}Co{sub 16}B{sub 6}Nb{sub 0.1} have been obtained from using (a) the hydrogenation, disproportionation, desorption and recombination (HDDR) process; (b) by varying of milling time and (c) with the addition of an oleic acid as a surfactant. The latter has been used to enhance milling condition by preventing the agglomeration of particles and hence to improve the intrinsic coercivity of the material. High-energy mechanical milling has been used to yield magnetic nanoparticles. Powders were characterized magnetically using vibrating sample magnetometer (VSM) and microstructurally by Scanning Electron Microscopy (SEM), Field Emission Gun SEM (FEG-SEM) and X-ray diffraction. (author)

  10. Formation of ball-milled Fe-Mo nanostructured powders

    Energy Technology Data Exchange (ETDEWEB)

    Moumeni, H. [Laboratoire de Magnetisme et de Spectroscopie des Solides, LM2S, Departement de Physique, Faculte des Sciences, Universite de Annaba, B.P. 12, 23000 Annaba-Algerie (Algeria) and Departement de Physique, Faculte des Sciences et de l' Ingenierie, Universite de Guelma, B.P. 401, 24000 Guelma-Algerie (Algeria)]. E-mail: hmoumeni@yahoo.fr; Alleg, S. [Laboratoire de Magnetisme et de Spectroscopie des Solides, LM2S, Departement de Physique, Faculte des Sciences, Universite de Annaba, B.P. 12, 23000 Annaba-Algerie (Algeria); Greneche, J.M. [Laboratoire de Physique de l' Etat Condense, UMR CNRS 6087, Universite du Maine, Faculte des Sciences, F-72085, Le Mans Cedex 9 (France)

    2006-08-10

    Nanostructured Fe-6 wt.%Mo powders were prepared by mechanical alloying in a high-energy planetary ball-mill. The structural changes and the kinetics of Mo dissolution were studied by using X-ray diffraction. The crystallite size reduction down to about 11 nm is accompanied by the introduction of internal strains up to 1.1% (root-mean square strain, rms). After 24 h of milling, a bcc Fe(Mo) solid solution is formed. The kinetics of Mo dissolution into the Fe matrix during the milling process can be described by two regimes characterized by small values of Avrami parameter which do not exceed unit.

  11. Tungsten-nanodiamond composite powders produced by ball milling

    Energy Technology Data Exchange (ETDEWEB)

    Nunes, D., E-mail: daniela.nunes@ist.utl.pt [Associacao Euratom/IST, Instituto de Plasmas e Fusao Nuclear, Instituto Superior Tecnico, Universidade Tecnica de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); LNEG, Estrada do Paco do Lumiar, 1649-038 Lisboa (Portugal); ICEMS, Instituto Superior Tecnico, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Livramento, V. [Associacao Euratom/IST, Instituto de Plasmas e Fusao Nuclear, Instituto Superior Tecnico, Universidade Tecnica de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); LNEG, Estrada do Paco do Lumiar, 1649-038 Lisboa (Portugal); Mardolcar, U.V. [Departamento de Fisica, Instituto Superior Tecnico, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Centro de Ciencias Moleculares e Materiais, Faculdade de Ciencias da Universidade de Lisboa, Campo Grande, 1749-016 Lisboa (Portugal); Correia, J.B. [LNEG, Estrada do Paco do Lumiar, 1649-038 Lisboa (Portugal); Carvalho, P.A. [ICEMS, Instituto Superior Tecnico, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Departamento de Bioengenharia, Instituto Superior Tecnico, Av. Rovisco Pais, 1049-001 Lisboa (Portugal)

    2012-07-15

    The major challenge in producing tungsten-nanodiamond composites by ball milling lies in successfully dispersing carbon nanoparticles in the metallic matrix while keeping carbide formation at a minimum. Processing windows for carbide minimization have been established through systematic variation of the nanodiamond fraction, milling energy and milling time. Materials characterization has been carried out by X-ray diffraction, scanning and transmission electron microscopy and microhardness testing. Nanostructured matrices with homogeneously dispersed particles that preserved the diamond structure have been produced. Differential thermal analysis has been used to evaluate the composites thermal stability.

  12. 1992 Colorado Economic Impact Study for the US Department of Energy and Colorado Department of Health Uranium Mill Tailings Remedial Action (UMTRA) Project

    International Nuclear Information System (INIS)

    1991-01-01

    The findings of the 1992 Colorado Economic Impact Study (CEIS) for the Uranium Mill Tailings Remedial Action (UMTRA) Project are outlined below. All dollar amounts used in the study are in year-of-expenditure dollars. The total funding requirement for the State of Colorado for the UMTRA Project is estimated to be $66.8 million, or 10 percent of the remedial action costs for the UMTRA Project in Colorado. The UMTRA Project will generate $487.5 million in gross labor income in Colorado between 1983 and 1996. This includes $54.4 million in state and local tax revenues and $41.2 million in federal individual income tax revenues. The net economic benefit of the UMTRA Project to Colorado is $355.1 million. For every dollar the State of Colorado invests in the UMTRA Project, it will realize $5.32 in gross labor income. The employment impact to the Western Slope region is significant. The UMTRA Project will create a total employment impact of 13,749 fulltime equivalents (FTES) spread over. a period of 13 years in seven site areas. Nearly 100 percent of the labor will be drawn from the local communities. The State of Colorado's Western Slope is anticipated to be minimally impacted by the phaseout of the UMTRA Project. Unlike industries that shut down operations without warning, the UMTRA Project workers, local government, and businesses know the schedule for completion and can consider and prepare for the impact of UMTRA Project conclusion. Further, because the majority of the work force is local, there has not been a significant investment in each community's infrastructure. Any small increases in the infrastructure will not be abandoned at the end of the UMTRA Project due to a marked increase in migration out of the local community

  13. Shear Roll Mill Reactivation

    Science.gov (United States)

    2012-09-13

    pneumatically operated paste dumper and belt conveyor system , the loss in weight feeder system , the hydraulically operated shear roll mill, the pellet...out feed belt conveyor , and the pack out system comprised of the metal detector, scale, and pack out empty and full drum roller conveyors . Page | 4...process equipment sprinkler protection systems , and the 5 psig steam supply serving the building heating and make-up air systems . It also included

  14. Phosphocreatine, an Intracellular High-Energy Compound, is Found in the Extracellular Fluid of the Seminal Vesicles in Mice and Rats

    Science.gov (United States)

    Lee, H. J.; Fillers, W. S.; Iyengar, M. R.

    1988-10-01

    High levels of phosphocreatine, a compound known to serve as an intracellular energy reserve, were found in the fluid contained in seminal vesicle glands. The concentrations of phosphocreatine in the extracellular fluid in the mouse and rat were found to be 5.6 ± 1.6 and 2.2 ± 0.8 μ mol/g, respectively, which are higher than the intracellular levels reported for smooth muscles. The creatine concentrations in the seminal vesicular fluid from these two species were 22.8 ± 3.1 and 13.0 ± 5.3 μ mol/g, respectively. These creatine levels are approximately 100 and 65 times higher than the creatine levels in mammalian blood. Smaller amounts of ATP (phosphocreatine/ATP ratio of 20-40) and traces of ADP were also found. Comparison of the pattern of distribution of macromolecules (proteins and DNA) with the distribution of phosphocreatine between the cells and the fluid of the seminal vesicle indicates that cell lysis did not account for the phosphocreatine in the seminal vesicle fluid. Rather, the available evidence strongly suggests that this high-energy compound is actively secreted. We found that in the testes, the sperm are exposed to the highest known creatine concentration in any mammalian tissue studied. Based on these results and other recent reports, we propose that the extracellular phosphocreatine, ATP, and creatine are involved in sperm metabolism.

  15. Domestic uranium mining and milling industry 1991

    International Nuclear Information System (INIS)

    1992-12-01

    This report was prepared by the Energy Information Administration to provide the Secretary of Energy with basic data and analyses for ninth annual determination of the viability of the domestic uranium mining and milling industry. A viability determination is required annually, for the years 1983 through 1992, by Section 170B of the Nuclear Regulatory Commission (NRC) Authorization Act of 1983, Public Law 97-415, which amend the Atomic Energy Act of 1954. Topics include: evolution of the U.S. uranium industry; nuclear power requirements and uranium industry projections; and attributes of industry viability

  16. Gravitating Yang--Mills fields in all dimensions

    OpenAIRE

    Radu, Eugen; Tchrakian, D. H.

    2009-01-01

    A classification of gravitating Yang--Mills systems in all dimensions is presented. These systems are set up so that they support finite energy solutions. Both regular and black hole solutions are considered, the former being the limit of the latter for vanishing event horizon radius. Special attention is paid to systems necessarily involving higher order Yang--Mills curvature terms, along with the option of incorporating higher order terms in the Riemann curvature. The scope here is restrict...

  17. Geothermal Mill Redevelopment Project in Massachusetts

    Energy Technology Data Exchange (ETDEWEB)

    Vale, A.Q.

    2009-03-17

    Anwelt Heritage Apartments, LLC redeveloped a 120-year old mill complex into a mixed-use development in a lower-income neighborhood in Fitchburg, Massachusetts. Construction included 84 residential apartments rented as affordable housing to persons aged 62 and older. The Department of Energy (“DOE”) award was used as an essential component of financing the project to include the design and installation of a 200 ton geothermal system for space heating and cooling.

  18. Kinetic reduction of mill scale via hydrogen

    Directory of Open Access Journals (Sweden)

    Gaballah N.M.

    2014-01-01

    Full Text Available Mill scale is very attractive industrial waste since it is rich in iron (about = 72 % Fe and it is suiTab. for direct recycling to the blast furnace via sintering plant. In this paper the characterizations of raw materials were studied by different methods of analyses. The produced briquettes were reduced with different amounts of hydrogen at varying temperatures, and the reduction kinetics was determined. Two models were applied and the energy of activation was calculated.

  19. Environmental impact of uranium mining and milling

    International Nuclear Information System (INIS)

    Dory, A.B.

    1981-08-01

    The Atomic Energy Control Board is now involved from the early planning stages in the development of uranium mine/mill facilities. As a result, new facilities (including tailings management areas) are designed and developed to meet a high standard. The impact of the mines and tailings areas in the Elliot Lake area on ground and surface waters and air quality is discussed in detail

  20. Multifractal properties of ball milling dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Budroni, M. A., E-mail: mabudroni@uniss.it; Pilosu, V.; Rustici, M. [Dipartimento di Chimica e Farmacia, Università degli Studi di Sassari, Via Vienna 2, Sassari 07100 (Italy); Delogu, F. [Dipartimento di Ingegneria Meccanica, Chimica, e dei Materiali, Università degli Studi di Cagliari, via Marengo 2, Cagliari 09123 (Italy)

    2014-06-15

    This work focuses on the dynamics of a ball inside the reactor of a ball mill. We show that the distribution of collisions at the reactor walls exhibits multifractal properties in a wide region of the parameter space defining the geometrical characteristics of the reactor and the collision elasticity. This feature points to the presence of restricted self-organized zones of the reactor walls where the ball preferentially collides and the mechanical energy is mainly dissipated.

  1. High energy mechano-chemical milling: Convenient approach to synthesis of LiMn1.5Ni0.5O4 high voltage cathode for lithium ion batteries

    International Nuclear Information System (INIS)

    Datta, Moni Kanchan; Ramanathan, Madhumati; Jampani, Prashanth; Saha, Partha; Epur, Rigved; Kadakia, Karan; Chung, Sung Jae; Patel, Prasad; Gattu, Bharat; Manivannan, Ayyakkannu; Kumta, Prashant N.

    2014-01-01

    Graphical abstract: Nanostructured high voltage spinel phase of LiMn 1.5 Ni 0.5 O 4 (LMNO) of particle size ∼10–40 nm has been synthesized by a cost effective high energy mechanical milling (HEMM) approach followed by low temperature thermal treatments. High energy mechanical milling of lithium and manganese oxide precursors followed by moderate heat treatment results in the formation of single phase of LMNO, the high voltage spinel phase. The nanostructured LMNO has been studied as a high voltage cathode for lithium ion rechargeable batteries. Cyclic voltammetry as well as the differential capacity plots of nanostructured LMNO show the occurrence of two major reversible reactions occurring in the potential window of ∼2–3.6 V and ∼3.6–5.1 V with an associated specific capacity ∼105 mAh/g and ∼128 mAh/g, respectively. The nanostructured LMNO synthesized by the HEMM process followed by thermal treatments at ∼773 K, ∼873 K and ∼973 K shows a reversible capacity ∼120–110 mAh/g when cycled at a rate of ∼20 mA/g (∼C/6) in the potential window ∼3.6–5.1 V. Furthermore, the nanostructured HEMM derived LMNO shows a moderate rate capability with a capacity retention ∼87 mAh/g when cycled at ∼80 mA/g (∼C) rate. - Highlights: • Generation of LiMn 1.5 Ni 0.5 O 4 (LMNO) spinel by a cost effective HEMM process. • HEMM derived LMNO spinel phase shows a capacity of ∼128 mAh/g. • HEMM derived spinel exhibits a capacity retention of ∼87 mAh/g at ∼1C rate. • SEM analysis shows good structural integrity of the cycled electrode. • Charge transfer resistance increase during cycling causes capacity fade. - Abstract: The high voltage spinel form of LiMn 1.5 Ni 0.5 O 4 (LMNO) with a particle size ∼10–40 nm has been synthesized for the first time using high energy mechanical milling (HEMM) followed by low temperature thermal treatments using Li 2 O, MnO 2 and NiO as the starting precursors. The nanostructured LMNO cathode

  2. Effect of ball milling process on coercivity of nanocrystalline SmCo5 magnets

    Science.gov (United States)

    Fang, Lei; Zhang, Tianli; Wang, Hui; Jiang, Chengbao; Liu, Jinghua

    2018-01-01

    In this paper, the effect of ball milling process on remanence and coercivity of nanocrystalline SmCo5 magnets was systematically investigated. Nanocrystalline SmCo5 magnets were prepared by high energy ball milling and spark plasma sintering. And their vast difference of remanence and coercivity were analyzed thoroughly. The anisotropic SmCo5 magnets prepared by wet-milling with surfactant (oleylamine, OY) have high remanence, but the coercivity is much lower than the isotropic magnets prepared by dry-milling. Further analysis indicates the milling process induced changes on the size and shape of grains are the key factors influencing the coercivity. The amorphous powders prepared by dry-milling were crystallized during sintering and the magnets have small and homogeneous grains, while the anisotropic nanoflakes prepared by wet-milling could be well oriented but the magnets have lower coercivity due to the larger and inhomogeneous grains.

  3. 78 FR 69663 - Jonathan and Jayne Chase Troy Mills Hydroelectric Inc.; Notice of Transfer of Exemption

    Science.gov (United States)

    2013-11-20

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 13381-007] Jonathan and Jayne Chase Troy Mills Hydroelectric Inc.; Notice of Transfer of Exemption 1. By letter filed October 15... Hydroelectric Project, FERC No. 13381, originally issued December 2, 2011,\\1\\ has been transferred to Troy Mills...

  4. 7 CFR 868.310 - Grades and grade requirements for the classes Long Grain Milled Rice, Medium Grain Milled Rice...

    Science.gov (United States)

    2010-01-01

    ... Grain Milled Rice, Medium Grain Milled Rice, Short Grain Milled Rice, and Mixed Milled Rice. (See also Â... Milled Rice Principles Governing Application of Standards § 868.310 Grades and grade requirements for the classes Long Grain Milled Rice, Medium Grain Milled Rice, Short Grain Milled Rice, and Mixed Milled Rice...

  5. Uranium-mill appraisal program

    International Nuclear Information System (INIS)

    Everett, R.J.; Cain, C.L.

    1982-08-01

    The results of special team appraisals at NRC-licensed uranium mills in the period May to November 1981 are reported. Since the Three Mile Island accident, NRC management has instituted a program of special team appraisals of radiation protection programs at certain NRC-licensed facilities. These appraisals were designed to identify weaknesses and strengths in NRC-licensed programs, including those areas not covered by explicit regulatory requirements. The regulatory requirements related to occupational radiation protection and environmental monitoring at uranium mills have been extensively upgraded in the past few years. In addition, there was some NRC staff concern with respect to the effectiveness of NRC licensing and inspection programs. In response to this concern and to changes in mill requirements, the NRC staff recommended that team appraisals be conducted at mills to determine the adequacy of mill programs, the effectiveness of the new requirements, and mill management implementation of programs and requirements. This report describes the appraisal scope and methodology as well as summary findings and conclusions. Significant weaknesses identified during the mill appraisals are discussed as well as recommendations for improvements in uranium mill programs and mill licensing and inspection

  6. Milling induced amorphisation and recrystallization of α-lactose monohydrate.

    Science.gov (United States)

    Badal Tejedor, Maria; Pazesh, Samaneh; Nordgren, Niklas; Schuleit, Michael; Rutland, Mark W; Alderborn, Göran; Millqvist-Fureby, Anna

    2018-02-15

    Preprocessing of pharmaceutical powders is a common procedure to condition the materials for a better manufacturing performance. However, such operations may induce undesired material properties modifications when conditioning particle size through milling, for example. Modification of both surface and bulk material structure will change the material properties, thus affecting the processability of the powder. Hence it is essential to control the material transformations that occur during milling. Topographical and mechanical changes in surface properties can be a preliminary indication of further material transformations. Therefore a surface evaluation of the α-lactose monohydrate after short and prolonged milling times has been performed. Unprocessed α-lactose monohydrate and spray dried lactose were evaluated in parallel to the milled samples as reference examples of the crystalline and amorphous lactose structure. Morphological differences between unprocessed α-lactose, 1 h and 20 h milled lactose and spray dried lactose were detected from SEM and AFM images. Additionally, AFM was used to simultaneously characterize particle surface amorphicity by measuring energy dissipation. Extensive surface amorphicity was detected after 1 h of milling while prolonged milling times showed only a moderate particle surface amorphisation. Bulk material characterization performed with DSC indicated a partial amorphicity for the 1 h milled lactose and a fully amorphous thermal profile for the 20 h milled lactose. The temperature profiles however, were shifted somewhat in the comparison to the amorphous reference, particularly after extended milling, suggesting a different amorphous state compared to the spray-dried material. Water loss during milling was measured with TGA, showing lower water content for the lactose amorphized through milling compared to spray dried amorphous lactose. The combined results suggest a surface-bulk propagation of the amorphicity during

  7. The Chinese red dragon and red capitalism: a thousand opportunities. [Energy in China]. Le dragon Chinois et le capitalisme rouge: les mille opportunites

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    On May 11, China has invited foreign investors to assist it in undertaking its oil drilling program, raising output to 200 million tons in the year 2000, as against the 139 million tons planned in 1993. This paper describes China situation in the energy field and gives forecasting on the needs in the year 2000.

  8. All order linearized hydrodynamics from fluid-gravity correspondence

    Science.gov (United States)

    Bu, Yanyan; Lublinsky, Michael

    2014-10-01

    Using fluid-gravity correspondence, we determine the (linearized) stress energy tensor of N=4 super-Yang-Mills theory at strong coupling with all orders in derivatives of fluid velocity included. We find that the dissipative effects are fully encoded in the shear term and a new one, which emerges starting from the third order. We derive, for the first time, closed linear holographic renormalization group flow-type equations for (generalized) momenta-dependent viscosity functions. In the hydrodynamic regime, we obtain the stress tensor up to third order in derivative expansion analytically. We then numerically determine the viscosity functions up to large momenta. As a check of our results, we also derive the generalized Navier-Stokes equations from the Einstein equations in the dual gravity.

  9. Accelerated aging tests of liners for uranium mill tailings disposal

    International Nuclear Information System (INIS)

    Barnes, S.M.; Buelt, J.L.; Hale, V.Q.

    1981-11-01

    This document describes the results of accelerated aging tests to determine the long-term effectiveness of selected impoundment liner materials in a uranium mill tailings environment. The study was sponsored by the US Department of Energy under the Uranium Mill Tailings Remedial Action Project. The study was designed to evaluate the need for, and the performance of, several candidate liners for isolating mill tailings leachate in conformance with proposed Environmental Protection Agency and Nuclear Regulatory Commission requirements. The liners were subjected to conditions known to accelerate the degradation mechanisms of the various liners. Also, a test environment was maintained that modeled the expected conditions at a mill tailings impoundment, including ground subsidence and the weight loading of tailings on the liners. A comparison of installation costs was also performed for the candidate liners. The laboratory testing and cost information prompted the selection of a catalytic airblown asphalt membrane and a sodium bentonite-amended soil for fiscal year 1981 field testing

  10. Coexistence of short- and long-range ferromagnetic order in nanocrystalline Fe2Mn1-xCuxAl (x=0.0, 0.1 and 0.3) synthesized by high-energy ball milling

    Science.gov (United States)

    Thanh, Tran Dang; Nanto, Dwi; Tuyen, Ngo Thi Uyen; Nan, Wen-Zhe; Yu, YiKyung; Tartakovsky, Daniel M.; Yu, S. C.

    2015-11-01

    In this work, we prepared nanocrystalline Fe2Mn1-xCuxAl (x=0.0, 0.1 and 0.3) powders by the high energy ball milling technique, and then studied their critical properties. Our analysis reveals that the increase of Cu-doping concentration (up to x=0.3) in these powders leads to a gradual increase of the ferromagnetic-paramagnetic transition temperature from 406 to 452 K. The Banerjee criterion suggests that all the samples considered undergo a second-order phase transition. A modified Arrott plot and scaling analysis indicate that the critical exponents (β=0.419 and 0.442, γ=1.082 and 1.116 for x=0.0 and 0.1, respectively) are located in between those expected for the 3D-Heisenberg and the mean-field models; the values of β=0.495 and γ=1.046 for x=0.3 sample are very close to those of the mean-field model. These features reveal the coexistence of the short- and long-range ferromagnetic order in the nanocrystalline Fe2Mn1-xCuxAl powders. Particularly, as the concentration of Cu increases, values of the critical exponent shift towards those of the mean-field model. Such results prove the Cu doping favors establishing a long-range ferromagnetic order.

  11. Phase Transitions in Mechanically Milled Mn-Al-C Permanent Magnets

    Directory of Open Access Journals (Sweden)

    Michael J. Lucis

    2014-04-01

    Full Text Available Mn-Al powders were prepared by rapid solidification followed by high-energy mechanical milling. The rapid solidification resulted in single-phase ε. The milling was performed in both the ε phase and the τ phase, with the τ-phase formation accomplished through a heat treatment at 500 °C for 10 min. For the ε-milled samples, the conversion of the ε to the τ phase was accomplished after milling via the same heat treatment. Mechanical milling induced a significant increase in coercivity in both cases, reaching 4.5 kOe and 4.1 kOe, respectively, followed by a decrease upon further milling. The increase in coercivity was the result of grain refinement induced by the high-energy mechanical milling. Additionally, in both cases a loss in magnetization was observed. Milling in the ε phase showed a smaller decrease in the magnetization due to a higher content of the τ phase. The loss in magnetization was attributed to a stress-induced transition to the equilibrium phases, as no site disorder or oxidation was observed. Surfactant-assisted milling in oleic acid also improved coercivity, but in this case values reached >4 kOe and remained stable at least through 32 h of milling.

  12. Stable Yang-Mills connections on special holonomy manifolds

    Science.gov (United States)

    Huang, Teng

    2017-06-01

    We prove that energy minimizing Yang-Mills connections on a compact G2-manifold has holonomy equal to G2 are G2-instantons, subject to an extra condition on the curvature. Furthermore, we show that energy minimizing connections on a compact Calabi-Yau 3-fold that has holonomy equal to SU(3) subject to a similar condition are holomorphic.

  13. Completion of the uranium mill tailings remedial project and cleanup of the former mill site at Grand Junction, Colorado

    International Nuclear Information System (INIS)

    Rael, G.J.; Cox, S.W.; Artiglia, E.W.

    2000-01-01

    The United States Department of Energy's Uranium Mill Tailings Remedial Action (UMTRA) Surface Project has successfully completed the cleanup of 22 former uranium mill sites, more than 5400 vicinity properties, and has constructed 18 entombment cells. The Project has recently received the United States Nuclear Regulatory Commission's approval and certification for the last two disposal sites, with these sites being placed under the general license for long term custodial care of residual radioactive material. The UMTRA site located at Grand Junction, Colorado is a good example of the technical, political, economic, and public relations challenges that were overcome in achieving success. The UMTRA Team discussed, negotiated, planned, and eventually acted on this uranium mill tailings problem and brought the project to a successful conclusion for the community. From the early 1940s through the 1970s, uranium ore was mined in significant quantities under United States federal contracts for the government's national defence programmes, i.e. the Manhattan Engineering District and Atomic Energy Commission programmes. The problem started as the need for uranium decreased in the late 1960s, resulting in mills shutting down, leaving behind large quantities of process waste tailings and contaminated mill buildings. The former Climax Uranium Company mill site in Grand Junction was one of the largest of these sites. (author)

  14. Energy efficiency project: continuous rolling mill profiles plant of Barra Mansa Votorantim Siderurgia; Projeto de eficiencia energetica: laminador continuo de perfis da Usina Barra Mansa Votorantim Siderurgia

    Energy Technology Data Exchange (ETDEWEB)

    Decnop, Luiz Eduardo Machado [LD Engenharia Ltda, Belo Horizonte, MG (Brazil); Franca, Rafael Latini; Silva, Bruno Jose Carvalho; Antunes, Raphael Jose Simoes [Votorantim Siderurgia, Volta Redonda, RJ (Brazil)

    2011-12-21

    This work shows the development and implementation of a plan to increase energy efficiency and consequent reduction in production costs of profiles. The plant has a varied mix, large differences among products (1 kg/m to 30 kg/m) that resulting in a large gaps between bars and high level of interruption. It was necessary to reduce the impacts of fixed charges that weighed heavily in the cost. The methodology was to identify, among the main elements contributing to the consumption of electricity, what is the real need of each input as the quality, quantity, intensity and permanence, to perform strictly their intended function in the process. Then the comparison of these results with the engineering solutions adopted in the current design of the equipment. Thus was taken to waste all resources available beyond the strict needs. This ranking conducted the study to optimize the delivery of each resource taking into account the difficulty and risk of possible technical solutions, taking as a premise to develop definitive solutions with full automation of security functions to ensure stability and security of gains. The results were the reduction of 147 kWh/t to 105 kWh/t in the LCP (-37%), and a 50% reduction in energy expended in the WTP. (author)

  15. Complexity in fluids

    International Nuclear Information System (INIS)

    Bayly, B.

    1991-01-01

    Fluids are basically very simple things. The fluids encountered all the time - air, water, milk, coffee, etc. - are undramatic. One blob of a given fluid looks much like any other, except for such gross properties as volume or mass. Of course, blobs of fluid come in different shapes. However, it's easy to change the shape of a blob of fluid, with the result that we rarely think of the shape of a fluid blob as a defining property. In fact, a blob that starts with one shape can be deformed into almost any other shape, with arbitrarily small input of energy. When one talks about lumps of a solid, in contrast, shape is important. This is because it takes work, i.e., energy, to change the shape of a solid. Making a small deformation from some rest configuration takes a small amount of energy, and a large deformation takes a lot of energy. Sometimes, as in idealized elastic systems, the required energy goes to infinity as the deformation becomes unbounded. Real solids usually break if you deform them enough; all subsequent deformations cost no energy. Basically, a finite deformation requires finite energy. Complexity arises in fluid systems because the shape of a blob of fluid is indeterminate. Nothing prevents an initially simple fluid blob from deforming into the weirdest shape imaginable. It is the absence of any kind of blob-shape constraint that allows complexity to enter fluid science. During these lectures the author briefly describes a few areas in which complexity arises and has to be dealt with. These lectures will be roughly divided as follows: (1) physical and mathematical description of fluids and flows; (2) flow transport and ergodic theory; (3) magnetic dynamos and related problems; (4) flow instabilities; (5) turbulence

  16. An energy stable evolution method for simulating two-phase equilibria of multi-component fluids at constant moles, volume and temperature

    KAUST Repository

    Kou, Jisheng

    2016-02-25

    In this paper, we propose an energy-stable evolution method for the calculation of the phase equilibria under given volume, temperature, and moles (VT-flash). An evolution model for describing the dynamics of two-phase fluid system is based on Fick’s law of diffusion for multi-component fluids and the Peng-Robinson equation of state. The mobility is obtained from diffusion coefficients by relating the gradient of chemical potential to the gradient of molar density. The evolution equation for moles of each component is derived using the discretization of diffusion equations, while the volume evolution equation is constructed based on the mechanical mechanism and the Peng-Robinson equation of state. It is proven that the proposed evolution system can well model the VT-flash problem, and moreover, it possesses the property of total energy decay. By using the Euler time scheme to discretize this evolution system, we develop an energy stable algorithm with an adaptive choice strategy of time steps, which allows us to calculate the suitable time step size to guarantee the physical properties of moles and volumes, including positivity, maximum limits, and correct definition of the Helmhotz free energy function. The proposed evolution method is also proven to be energy-stable under the proposed time step choice. Numerical examples are tested to demonstrate efficiency and robustness of the proposed method.

  17. Einstein-Yang-Mills from pure Yang-Mills amplitudes

    OpenAIRE

    Nandan, Dhritiman; Plefka, Jan; Schlotterer, Oliver; Wen, Congkao

    2016-01-01

    We present new relations for scattering amplitudes of color ordered gluons and gravitons in Einstein-Yang-Mills theory. Tree-level amplitudes of arbitrary multiplicities and polarizations involving up to three gravitons and up to two color traces are reduced to partial amplitudes of pure Yang-Mills theory. In fact, the double-trace identities apply to Einstein-Yang-Mills extended by a dilaton and a B-field. Our results generalize recent work of Stieberger and Taylor for the single graviton ca...

  18. Radiation health and safety aspects in uranium milling

    International Nuclear Information System (INIS)

    Smart, B.C.

    1982-01-01

    This presentation deals mainly with radiation levels associated with the uranium milling operations, including yellowcake production. The regulation of uranium mills has not received much attention in the past because radiation levels have been generally low, and uranium milling has been substantially free of occupational illness. More attention is being directed towards minimizing exposures, and the Canadian Atomic Energy Control Board is working on new regulations which will reflect the recommendations of various hearings and the International Commission on Radiological Protection. Emphasis is now being placed on improving monitoring methods. At the beginning of 1982 a gamma dosimetry program will be put into effect for all uranium mine and mill workers. An improved method is also being sought to determine radon daughter exposures more accurately. It is expected that a better knowledge of monitoring and assessing thoron daughter levels in mine and mill facilities will be obtained soon. This radiation contribution will be included when calculating a combined radiation exposure factor for individual workers. Programs are underway to better monitor and assess uranium dust inhalation. Initial studies indicate that the present precautions taken to avoid dust inhalation at the mills are effective. A more complete study will be undertaken in 1982

  19. Roll compaction/dry granulation: comparison between roll mill and oscillating granulator in dry granulation.

    Science.gov (United States)

    Sakwanichol, Jarunee; Puttipipatkhachorn, Satit; Ingenerf, Gernot; Kleinebudde, Peter

    2012-01-01

    Different experimental factorial designs were employed to evaluate granule properties obtained from oscillating granulator and roll mill. Four oscillating-granulator parameters were varied, i.e. rotor speed, oscillating angle, aperture of mesh screen and rotor type. Six roll-mill parameters that were throughput, speed ratio in both first and second stages, gap between roll pair in both stages and roll-surface texture were also investigated. Afterwards, the granule properties obtained from two milling types with similar median particle size were compared. All milling parameters in both milling types affected significantly the median particle size, size distribution and amount of fine particles (P rotor types of oscillating granulator on fines. Only three milling parameters influenced significantly the flowability (P < 0.05). These were the throughput and the gap size in the first stage of roll mill and the sieve size of oscillating granulator. In comparison between milling types, the differences of granule properties were not practically relevant. However, the roll mill had much higher capacity than the oscillating granulator about seven times, resulting in improving energy savings per unit of product. Consequently, the roll mill can be applied instead of oscillating granulator for roll compaction/dry granulation technique.

  20. Investigation of the milling-induced thermal behavior of crystalline and amorphous griseofulvin.

    Science.gov (United States)

    Trasi, Niraj S; Boerrigter, Stephan X M; Byrn, Stephen Robert

    2010-07-01

    To gain a better understanding of the physical state and the unusual thermal behavior of milled griseofulvin. Griseofulvin crystals and amorphous melt quench samples were milled in a vibrating ball mill for different times and then analyzed using differential scanning calorimetry (DSC) and powder X-ray diffraction (PXRD). Modulated DSC (mDSC) and annealing studies were done for the milled amorphous samples to further probe the effects of milling. Milling of griseofulvin crystals results in decrease in crystallinity and amorphization of the compound. A double peak is seen for crystallization in the DSC, which is also seen for the milled melt quench sample. Both enthalpy and temperature of crystallization decrease for the milled melt quenched sample. Tg is visible under the first peak with the mDSC, and annealing shows that increasing milling time results in faster crystallization upon storage. Milling of griseofulvin results in the formation of an amorphous form and not a mesophase. It increases the amount of surface created and the overall energy of the amorphous griseofulvin, which leads to a decreased temperature of crystallization. The two exotherms in the DSC are due to some particles having nuclei on the surface.

  1. Techno-Economic Assessment of Heat Transfer Fluid Buffering for Thermal Energy Storage in the Solar Field of Parabolic Trough Solar Thermal Power Plants

    Directory of Open Access Journals (Sweden)

    Jorge M. Llamas

    2017-08-01

    Full Text Available Currently, operating parabolic trough (PT solar thermal power plants, either solar-only or with thermal storage block, use the solar field as a heat transfer fluid (HTF thermal storage system to provide extra thermal capacity when it is needed. This is done by circulating heat transfer fluid into the solar field piping in order to create a heat fluid buffer. In the same way, by oversizing the solar field, it can work as an alternative thermal energy storage (TES system to the traditionally applied methods. This paper presents a solar field TES model for a standard solar field from a 50-MWe solar power plant. An oversized solar model is analyzed to increase the capacity storage system (HTF buffering. A mathematical model has been developed and different simulations have been carried out over a cycle of one year with six different solar multiples considered to represent the different oversized solar field configurations. Annual electricity generation and levelized cost of energy (LCOE are calculated to find the solar multiple (SM which makes the highest solar field thermal storage capacity possible within the minimum LCOE.

  2. On the exponentiation of leading infrared divergences in massless Yang-Mills theories

    International Nuclear Information System (INIS)

    Frenkel, J.; Garcia, R.L.

    1977-01-01

    We derive, in the axial gauge, the effective U-matrix which governs the behaviour of leading infrared singularities in the self-energy functions of Yang-Mills particles. We then show in a very simple manner, that these divergences, which determine the leading singularities in massless Yang-Mills theories, exponentiate [pt

  3. Industrial recovered-materials-utilization targets for the textile-mill-products industry

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-01-01

    The Congress, in the National Energy Conservation and Policy Act of 1978 (NECPA), directed the Department of Energy to establish materials recovery targets for the metals and metal products, paper and allied products, rubber, and textile-mill-products industries. The targets were developed to provide incentives for using energy-saving recorded materials and to provied a yardstick for measuring progress and improvement in this endeavor. The NECPA indicates that the targets should represent the maximum technically and economically feasible increase in the use of energy-saving recovered materials that each industry can achieve progressively by January 1, 1987. Materials affected by recovered-materials targets include and are limited to aluminum, copper, lead, zinc, iron, steel, paper and associated products, textile-mill, products, and rubber. Using information gathered from the textile-mill-products industry and from other textile-relaed sources, DOE has developed recovered materials targets for that industry. This report presents those targets and their basis and justification. Following an overview of the textile industry, the chapters are: Textile-Mill-Products Industry Operations; Economic Analysis of the Textile-Mill-Products Industry; Governmental and Regulatory Influence on the US Textile Industry; Current Mill Use of Recovered Materials in the Textile-Mill-Products Industry; Limitations on the Use of Recovered Materials in the US Textile-Mill-Products Industry; Materials-Recovery Targets; and Government and Industry Actions That Could Increase the Use of Recovered Materials.

  4. On d = 4 Yang-Mills instantons in a spherically symmetric background

    Science.gov (United States)

    Brihaye, Y.; Radu, E.

    2006-09-01

    We present arguments for the existence of self-dual Yang-Mills instantons for several spherically symmetric backgrounds with Euclidean signature. The time-independent Yang-Mills field has finite action and a vanishing energy momentum tensor and does not disturb the geometry. We conjecture the existence of similar solutions for any nonextremal SO(3)-spherically symmetric background.

  5. On $d=4$ Yang-Mills instantons in a spherically symmetric background

    OpenAIRE

    Brihaye, Yves; Radu, Eugen

    2006-01-01

    We present arguments for the existence of self-dual Yang-Mills instantons for several spherically symmetric backgrounds with Euclidean signature. The time-independent Yang-Mills field has finite action and a vanishing energy momentum tensor and does not disturb the geometry. We conjecture the existence of similar solutions for any nonextremal SO(3)-spherically symmetric background.

  6. Microcanonical-ensemble computer simulation of the high-temperature expansion coefficients of the Helmholtz free energy of a square-well fluid

    Science.gov (United States)

    Sastre, Francisco; Moreno-Hilario, Elizabeth; Sotelo-Serna, Maria Guadalupe; Gil-Villegas, Alejandro

    2018-02-01

    The Microcanonical Ensemble computer simulation method (MCE) is used to evaluate the perturbation terms $A_i$ of the Helmholtz free energy of a Square-Well (SW) fluid. The MCE method offers a very efficient and accurate procedure for the determination of perturbation terms of discrete-potential systems such as the SW fluid and surpass the standard NVT Canonical Ensemble Monte Carlo method, allowing the calculation of the first six expansion terms. Results are presented for the case of a SW potential with attractive ranges $1.1 \\le \\lambda \\le 1.8$. Using semiempirical representation of the MCE values for $A_i$, we also discuss the accuracy in the determination of the phase diagram of this system.

  7. Cryogenic Milling of Titanium Powder

    Directory of Open Access Journals (Sweden)

    Jiří Kozlík

    2018-01-01

    Full Text Available Ti Grade 2 was prepared by cryogenic attritor milling in liquid nitrogen and liquid argon. Two types of milling balls were used—stainless steel balls and heavy tungsten carbide balls. The effect of processing parameters on particle size and morphology, contamination of powder and its microhardness was investigated. Milling in liquid nitrogen was not feasible due to excessive contamination by nitrogen. Minor reduction of particle size and significant alterations in particle morphology depended on type of milling balls and application of stearic acid as processing control agent. Heavily deformed ultra-fine grained (UFG internal microstructure of powder particles was observed by the method of “transmission Kikuchi diffraction”.

  8. Application of Biomass from Palm Oil Mill for Organic Rankine Cycle to Generate Power in North Sumatera Indonesia

    Science.gov (United States)

    Nur, T. B.; Pane, Z.; Amin, M. N.

    2017-03-01

    Due to increasing oil and gas demand with the depletion of fossil resources in the current situation make efficient energy systems and alternative energy conversion processes are urgently needed. With the great potential of resources in Indonesia, make biomass has been considered as one of major potential fuel and renewable resource for the near future. In this paper, the potential of palm oil mill waste as a bioenergy source has been investigated. An organic Rankine cycle (ORC) small scale power plant has been preliminary designed to generate electricity. The working fluid candidates for the ORC plant based on the heat source temperature domains have been investigated. The ORC system with a regenerator has higher thermal efficiency than the basic ORC system. The study demonstrates the technical feasibility of ORC solutions in terms of resources optimizations and reducing of greenhouse gas emissions.

  9. Feasibility Study of Economics and Performance of Geothermal Power Generation at the Lakeview Uranium Mill Site in Lakeview, Oregon. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Hillesheim, M.; Mosey, G.

    2013-11-01

    The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Lakeview Uranium Mill site in Lakeview, Oregon, for a feasibility study of renewable energy production. The EPA contracted with the National Renewable Energy Laboratory (NREL) to provide technical assistance for the project. The purpose of this report is to describe an assessment of the site for possible development of a geothermal power generation facility and to estimate the cost, performance, and site impacts for the facility. In addition, the report recommends development pathways that could assist in the implementation of a geothermal power system at the site.

  10. Feasibility Study of Economics and Performance of Solar Photovoltaics at the Peru Mill Industrial Park in the City of Deming, New Mexico. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Kiatreungwattana, K.; Geiger, J.; Healey, V.; Mosey, G.

    2013-04-01

    The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Peru Mill Industrial Park site in the City of Deming, New Mexico, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this report is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site.

  11. Understanding Biomass Ignition in Power Plant Mills

    DEFF Research Database (Denmark)

    Schwarzer, Lars; Jensen, Peter Arendt; Glarborg, Peter

    2017-01-01

    Converting existing coal fired power plants to biomass is a readily implemented strategy to increase the share of renewable energy. However, changing from one fuel to another is not straightforward: Experience shows that wood pellets ignite more readily than coal in power plant mills or storages....... This is not very well explained by apply-ing conventional thermal ignition theory. An experimental study at lab scale, using pinewood as an example fuel, was conducted to examine self-heating and self-ignition. Supplemental experiments were performed with bituminous coal. Instead of characterizing ignition...

  12. Uranium mill tailings stabilization

    International Nuclear Information System (INIS)

    Hartley, J.N.; Koehmstedt, P.L.; Esterl, D.J.; Freeman, H.D.

    1980-02-01

    Uranium mill tailings pose a potential radiation health hazard to the public. Therefore, stabilization or disposal of these tailings in a safe and environmentally sound way is needed to minimize radon exhalation and other environmental hazards. One of the most promising concepts for stabilizing U tailings is the use of asphalt emulsion to contain radon and other hazardous materials within uranium tailings. This approach is being investigated at the Pacific Northwest Laboratory. Results of these studies indicate that a radon flux reduction of greater than 99% can be obtained using either a poured-on/sprayed-on seal (3.0 to 7.0 mm thick) or an admixture seal (2.5 to 12.7 cm thick) containing about 18 wt % residual asphalt. A field test was carried out in June 1979 at the Grand Junction tailings pile in order to demonstrate the sealing process. A reduction in radon flux ranging from 4.5 to greater than 99% (76% average) was achieved using a 15.2-cm (6-in.) admix seal with a sprayed-on top coat. A hydrostatic stabilizer was used to apply the admix. Following compaction, a spray coat seal was applied over the admix as the final step in construction of a radon seal. Overburden was applied to provide a protective soil layer over the seal. Included in part of the overburden was a herbicide to prevent root penetration

  13. Milling and dispersion of multi-walled carbon nanotubes in texanol

    Science.gov (United States)

    Darsono, Nono; Yoon, Dang-Hyok; Kim, Jaemyung

    2008-03-01

    Rheological results were used to determine the optimum type of dispersant and its concentration for six commercial dispersants for the dispersion of multi-walled carbon nanotube (MWCNT) agglomerates in texanol. An unsaturated polycarboxylic acid copolymer (BYK P-104) exhibited the optimum performance with the lowest MWCNT slurry viscosity in texanol. The cutting and dispersion efficiencies of MWCNTs with 20 wt.% of BYK P-104 dispersant were compared using conventional ball milling and high energy milling, whereby the latter was found to be more effective. High energy milling for 2 h produced a large portion of MWCNT agglomerates smaller than 150 nm, showing a drastic increase in slurry viscosity due to the dispersion into individual CNTs. On the other hand, 120 h ball milling was required to achieve the agglomerate size of 300 nm with less viscosity increase upon milling. Decrease in the degree of MWCNT crystallinity was observed by both milling, even though 2 h high energy milling showed slightly less damage than 120 h ball milling based on XRD and Raman spectroscopy results.

  14. Improving eco-sustainable characteristics and energy efficiency of evaporative fluid cooler via experimental and numerical study

    Directory of Open Access Journals (Sweden)

    Rašković Predrag O.

    2008-01-01

    Full Text Available This paper presents an on-going research project that aims to identify possibilities for wider use of evaporative cooling in process industry, especially the use of evaporative fluid cooler units. Experimental study is performed on small scale evaporative fluid cooler, while the correlation based model has been carried out to explore the detailed heat and mass transfer processes inside this unit. Numerical integration of mathematical model is executed by new approach, based on differential, collocation Simpson method. Proposed models have been verified by comparing the computed results with those obtained by the experimental measurements. The results of research will enable the creation of more comprehensive simulation software, with wider range of operating and construction parameters.

  15. 77 FR 24483 - Wausau Paper Mills, LLC; Notice of Final Land Management Plan and Soliciting Comments, Motions To...

    Science.gov (United States)

    2012-04-24

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 2161-032] Wausau Paper...: Wausau Paper Mills, LLC. e. Name of Project: Rhinelander Hydroelectric Project. f. Location: The upper.... Applicant Contact: Mr. Tim Hasbargen, Wausau Paper Mills, LLC, 515 Davenport St., Rhinelander, Wisconsin...

  16. From Herman Weyl to Yang and Mills to quantum chromodynamics

    Czech Academy of Sciences Publication Activity Database

    Chýla, Jiří

    2005-01-01

    Roč. 749, - (2005), 23c-32c ISSN 0375-9474 Institutional research plan: CEZ:AV0Z1010920 Keywords : quantum field theory * gauge invariance * Weyl, Yang , Mills * quarks * gluons Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 1.950, year: 2005

  17. Plasmas and fluids

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    Plasma and fluid physics includes the fields of fusion research and space investigation. This book discusses the most important advances in these areas over the past decade and recommends a stronger commitment to basic research in plasma and fluid physics. The book recommends that plasma and fluid physics be included in physics curriculums because of their increasing importance in energy and defense. The book also lists recent accomplishments in the fields of general plasma physics, fusion plasma confinement and heating, space and astrophysical plasmas, and fluid physics and lists research opportunities in these areas. A funding summary explains how research monies are allocated and suggests ways to improve their effectiveness

  18. Using the minimum principle for the Helmholtz free energy in the analysis of the equilibria of a van der Waals fluid

    International Nuclear Information System (INIS)

    Ascoli, Sergio; Malvestuto, Vincenzo

    2004-01-01

    For a fluid system, obeying a state equation of the van der Waals type, the gas and the liquid phases can coexist in equilibrium, at a given temperature, only if the volume of the system is kept fixed. Thus, in order to study the two-phase equilibria of a fluid system, it seemed quite natural to choose the molar volume as the independent variable, and, consequently, the Helmholtz free energy as the proper thermodynamic potential for the application of the minimum principle. Specific computations are here carried out for a single van der Waals fluid, namely, pure water at 300 0 C. As a result, the present treatment indicates a simple and effective way to identify the whole range of molar volumes where the equilibrium preferred by the system is a two-phase equilibrium. This range results to be wider than the interval of strict instability of the van der Waals isotherm. Finally, it is pointed out that all the results, obtained here for the van der Waals state equation, can be extended to all the state equations of the same type

  19. Energy research

    International Nuclear Information System (INIS)

    1979-03-01

    Status reports are given for the Danish Trade Ministry's energy research projects on uranium prospecting and extraction, oil and gas recovery, underground storage of district heating, electrochemical energy storage systems, wind mills, coal deposits, coal cambustion, energy consumption in buildings, solar heat, biogas, compost heat. (B.P.)

  20. Helical Feed Milling with MQL for Boring of Aluminum Alloy

    Science.gov (United States)

    Sasahara, Hiroyuki; Kawasaki, Makoto; Tsutsumi, Masaomi

    MQL is applied to the helical feed milling hole-making process of aluminum alloy. It is difficult to drill on aluminum alloy without cutting fluid because the adhesion to the tool leads to a chip jam, the tool breakage or low accuracy. By employing the helical feed milling, cutting temperature will decrease, each chip length will become short and a chip jam in a hole will be avoided, because the intermittent cutting is realized. As a result of employing the helical feed milling with MQL, it was shown that the shape error is decreased, a burr formation is decreased, machining temperature becomes low and the cutting force becomes small comparing with drilling process. Shape error by helical feed milling with MQL is comparable with that with flood coolant. In this case, small mist particle counts under 5μm, which affects working environment, are almost constant if the spindle speed varies. Scattered mist particle counts are less when MQL is employed over 20000 min-1 spindle speed comparing with the flood coolant.

  1. Uranium Mill Tailings Radiation Control Act of 1978

    International Nuclear Information System (INIS)

    Magee, J.

    1980-01-01

    The long-term environmental effects of the Uranium Mill Tailings Radiation Control Act of 1978 address the public health hazards of radioactive wastes and recognize the significance of this issue to public acceptance of nuclear energy. Title I of the Act deals with stabilizing and controlling mill tailings at inactive sites and classifies the sites by priority. It represents a major Federal commitment. Title II changes and strengthens Nuclear Regulatory Commission authority, but it will have little overall impact. It is not possible to assess the Act's effect because there is no way to know if current technology will be adequate for the length of time required. 76 references

  2. Development on a Hammer Mill with Separate Sieving Device

    OpenAIRE

    Ding Han; Yanhua Ma; Pei Wu; Liying Cao; Chuanzhong Xuan

    2012-01-01

    Hammer mills are widely used for material size reduction in food and feed industries. In this paper, a new hammer mill with separate sieving device has been designed and fabricated, in which the so-called material-circulation layer can not be formed and material being ground passes through the sieve by rotor throwing and air blowing without direct rubbing with the sieve. Thus the new machine has the advantages in high productivity, low energy consumption, low sieve wearing, and especially,  t...

  3. Einstein-Yang-Mills from pure Yang-Mills amplitudes

    International Nuclear Information System (INIS)

    Nandan, Dhritiman; Plefka, Jan; Schlotterer, Oliver; Wen, Congkao

    2016-01-01

    We present new relations for scattering amplitudes of color ordered gluons and gravitons in Einstein-Yang-Mills theory. Tree-level amplitudes of arbitrary multiplicities and polarizations involving up to three gravitons and up to two color traces are reduced to partial amplitudes of pure Yang-Mills theory. In fact, the double-trace identities apply to Einstein-Yang-Mills extended by a dilaton and a B-field. Our results generalize recent work of Stieberger and Taylor for the single graviton case with a single color trace. As the derivation is made in the dimension-agnostic Cachazo-He-Yuan formalism, our results are valid for external bosons in any number of spacetime dimensions. Moreover, they generalize to the superamplitudes in theories with 16 supercharges.

  4. Einstein-Yang-Mills from pure Yang-Mills amplitudes

    Energy Technology Data Exchange (ETDEWEB)

    Nandan, Dhritiman; Plefka, Jan [Institut für Physik and IRIS Adlershof, Humboldt-Universität zu Berlin,Zum Großen Windkanal 6, D-12489 Berlin (Germany); Schlotterer, Oliver [Max-Planck-Institut für Gravitationsphysik, Albert-Einstein-Institut,Am Mühlenberg 1, D-14476 Potsdam (Germany); Wen, Congkao [I.N.F.N. Sezione di Roma Tor Vergata,Via della Ricerca Scientifica, 00133 Roma (Italy)

    2016-10-14

    We present new relations for scattering amplitudes of color ordered gluons and gravitons in Einstein-Yang-Mills theory. Tree-level amplitudes of arbitrary multiplicities and polarizations involving up to three gravitons and up to two color traces are reduced to partial amplitudes of pure Yang-Mills theory. In fact, the double-trace identities apply to Einstein-Yang-Mills extended by a dilaton and a B-field. Our results generalize recent work of Stieberger and Taylor for the single graviton case with a single color trace. As the derivation is made in the dimension-agnostic Cachazo-He-Yuan formalism, our results are valid for external bosons in any number of spacetime dimensions. Moreover, they generalize to the superamplitudes in theories with 16 supercharges.

  5. Exploring the Environment/Energy Pareto Optimal Front of an Office Room Using Computational Fluid Dynamics-Based Interactive Optimization Method

    Directory of Open Access Journals (Sweden)

    Kangji Li

    2017-02-01

    Full Text Available This paper is concerned with the development of a high-resolution and control-friendly optimization framework in enclosed environments that helps improve thermal comfort, indoor air quality (IAQ, and energy costs of heating, ventilation and air conditioning (HVAC system simultaneously. A computational fluid dynamics (CFD-based optimization method which couples algorithms implemented in Matlab with CFD simulation is proposed. The key part of this method is a data interactive mechanism which efficiently passes parameters between CFD simulations and optimization functions. A two-person office room is modeled for the numerical optimization. The multi-objective evolutionary algorithm—non-dominated-and-crowding Sorting Genetic Algorithm II (NSGA-II—is realized to explore the environment/energy Pareto front of the enclosed space. Performance analysis will demonstrate the effectiveness of the presented optimization method.

  6. Equilibrium modeling of gasification: Gibbs free energy minimization approach and its application to spouted bed and spout-fluid bed gasifiers

    International Nuclear Information System (INIS)

    Jarungthammachote, S.; Dutta, A.

    2008-01-01

    Spouted beds have been found in many applications, one of which is gasification. In this paper, the gasification processes of conventional and modified spouted bed gasifiers were considered. The conventional spouted bed is a central jet spouted bed, while the modified spouted beds are circular split spouted bed and spout-fluid bed. The Gibbs free energy minimization method was used to predict the composition of the producer gas. The major six components, CO, CO 2 , CH 4 , H 2 O, H 2 and N 2 , were determined in the mixture of the producer gas. The results showed that the carbon conversion in the gasification process plays an important role in the model. A modified model was developed by considering the carbon conversion in the constraint equations and in the energy balance calculation. The results from the modified model showed improvements. The higher heating values (HHV) were also calculated and compared with the ones from experiments. The agreements of the calculated and experimental values of HHV, especially in the case of the circular split spouted bed and the spout-fluid bed were observed

  7. Parametric and working fluid analysis of a combined organic Rankine-vapor compression refrigeration system activated by low-grade thermal energy.

    Science.gov (United States)

    Saleh, B

    2016-09-01

    The potential use of many common hydrofluorocarbons and hydrocarbons as well as new hydrofluoroolefins, i.e. R1234yf and R1234ze(E) working fluids for a combined organic Rankine cycle and vapor compression refrigeration (ORC-VCR) system activated by low-grade thermal energy is evaluated. The basic ORC operates between 80 and 40 °C typical for low-grade thermal energy power plants while the basic VCR cycle operates between 5 and 40 °C. The system performance is characterized by the overall system coefficient of performance (COPS) and the total mass flow rate of the working fluid for each kW cooling capacity ([Formula: see text]). The effects of different working parameters such as the evaporator, condenser, and boiler temperatures on the system performance are examined. The results illustrate that the maximum COPS values are attained using the highest boiling candidates with overhanging T-s diagram, i.e. R245fa and R600, while R600 has the lowest [Formula: see text] under the considered operating conditions. Among the proposed candidates, R600 is the best candidate for the ORC-VCR system from the perspectives of environmental issues and system performance. Nevertheless, its flammability should attract enough attention. The maximum COPS using R600 is found to reach up to 0.718 at a condenser temperature of 30 °C and the basic values for the remaining parameters.

  8. Parametric and working fluid analysis of a combined organic Rankine-vapor compression refrigeration system activated by low-grade thermal energy

    Directory of Open Access Journals (Sweden)

    B. Saleh

    2016-09-01

    Full Text Available The potential use of many common hydrofluorocarbons and hydrocarbons as well as new hydrofluoroolefins, i.e. R1234yf and R1234ze(E working fluids for a combined organic Rankine cycle and vapor compression refrigeration (ORC-VCR system activated by low-grade thermal energy is evaluated. The basic ORC operates between 80 and 40 °C typical for low-grade thermal energy power plants while the basic VCR cycle operates between 5 and 40 °C. The system performance is characterized by the overall system coefficient of performance (COPS and the total mass flow rate of the working fluid for each kW cooling capacity (ṁtotal. The effects of different working parameters such as the evaporator, condenser, and boiler temperatures on the system performance are examined. The results illustrate that the maximum COPS values are attained using the highest boiling candidates with overhanging T-s diagram, i.e. R245fa and R600, while R600 has the lowest ṁtotal under the considered operating conditions. Among the proposed candidates, R600 is the best candidate for the ORC-VCR system from the perspectives of environmental issues and system performance. Nevertheless, its flammability should attract enough attention. The maximum COPS using R600 is found to reach up to 0.718 at a condenser temperature of 30 °C and the basic values for the remaining parameters.

  9. Current practices and options for confinement of uranium mill tailings

    International Nuclear Information System (INIS)

    1981-01-01

    At the United Nations Conference on the Human Environment, which took place in Stockholm from 4 to 6 June 1972, national governments were asked to explore, with the International Atomic Energy Agency and other appropriate international organizations, international co-operation on radioactive waste matters including those of mining and tailings disposal. Since that time the IAEA has been active in the field of uranium and thorium mill tailings management. As part of this activity, the present report describes current practices and options for confinement of uranium mill tailings. It is addressed to technical and administrative personnel who are involved in planning and implementing national and industrial programmes on the management of such tailings. In 1974 and 1975 the IAEA convened meetings of experts to review matters of interest and importance in the management of uranium and thorium mine and mill tailings. These activities led to the publication in 1976 of Management of Wastes from the Mining and Milling of Uranium and Thorium Ores, a Code of Practice and Guide to the Code, IAEA Safety Series No. 44. As a continuation of this activity, the IAEA is here dealing more specifically with the design and siting considerations for the management of uranium mill tailings

  10. Influence of Milling Conditions on the Hydriding Properties of Mg-C Nanocomposites

    Directory of Open Access Journals (Sweden)

    Hristina Stoyadinova

    2015-01-01

    Full Text Available Mg75 at.%, CB25 at.% (CB: carbon black composites were synthesized at different ball milling conditions (milling energy, milling duration, and environment and their hydriding properties were characterized by high-pressure DSC. The SEM observations revealed that the samples consist of 5–15 μm Mg particles, surrounded and in some cases coated by carbon particles. X-ray diffraction analysis showed that the Mg phase of all as-obtained composite powders is nanocrystalline with average crystallite size in the range 20–30 nm, depending on the milling conditions. The best hydriding properties, expressed in low-temperature hydriding (below 150°C and improved cycle life, showed the composites milled at dry conditions. This is obviously due mainly to the successful Mg surface protection by the carbon. Additional decrease of the hydriding temperature (<100°C was achieved applying higher-energy milling, but at the same time the cycling stability deteriorated, due to the extremely fine particles and microstructure achieved under these conditions. The composites milled in the presence of heptane showed rapid capacity decline during cycling as well. The observed difference in the hydriding behavior of the Mg-CB composites is attributed to the different coating efficiency of the carbon milled under different conditions with Mg, which is supposed to protect magnesium from oxidation and plays a catalytic role for the hydriding reaction.

  11. Wind Resource Assessment Report: Mille Lacs Indian Reservation, Minnesota

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez, Antonio C. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Robichaud, Robi [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2013-12-01

    The U.S. Environmental Protection Agency (EPA) launched the RE-Powering America's Land initiative to encourage development of renewable energy on potentially contaminated land and mine sites. EPA collaborated with the U.S. Department of Energy's (DOE's) National Renewable Energy Laboratory (NREL) and the Mille Lacs Band of Chippewa Indians to evaluate the wind resource and examine the feasibility of a wind project at a contaminated site located on the Mille Lacs Indian Reservation in Minnesota. The wind monitoring effort involved the installation of a 60-m met tower and the collection of 18 months of wind data at multiple heights above the ground. This report focuses on the wind resource assessment, the estimated energy production of wind turbines, and an assessment of the economic feasibility of a potential wind project sited this site.

  12. Collaborative Research: Nanopore Confinement of C-H-O Mixed Volatile Fluids Relevant to Subsurface Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Grady, Brian P. [Univ. of Oklahoma, Norman, OK (United States)

    2015-03-11

    The scientific objective of this proposal was to obtain a fundamental atomic- to macro-scale understanding of the sorptivity, structure and dynamics of simple and complex hydrocarbon (HC) fluids at mineral surfaces or within nanoporous matrices over temperatures, pressures and compositions encountered in near-surface and shallow crustal environments. The research supported by this award was complementary to that conducted by the group of Prof. David cole at Ohio State University. The scope of the present award was to utilize molecular-level modeling to provide critically important insights into the interfacial properties of mineral-volatile systems, assist in the interpretation of experimental data and predict fluid behavior beyond the limits of current experimental capability. During the past three years the effort has focused primarily on the behavior of C-H volatiles including methane (CH4) and propane (C3H8), mixed-volatile systems including hydrocarbon - CO2 with and without H2O present. The long-range goal is to quantitatively link structure, dynamics and reactivity in complex mineral-/C-H-O systems from the atomic to the molecular to the macroscopic levels. The results are relevant to areas of growing importance such as gas shale, HC-bearing hydrothermal systems, and CO2 storage.

  13. Gyroelastic fluids

    Energy Technology Data Exchange (ETDEWEB)

    Kerbel, G.D.

    1981-01-20

    A study is made of a scale model in three dimensions of a guiding center plasma within the purview of gyroelastic (also known as finite gyroradius-near theta pinch) magnetohydrodynamics. The (nonlinear) system sustains a particular symmetry called isorrhopy which permits the decoupling of fluid modes from drift modes. Isorrhopic equilibria are analyzed within the framework of geometrical optics resulting in (local) dispersion relations and ray constants. A general scheme is developed to evolve an arbitrary linear perturbation of a screwpinch equilibrium as an invertible integral transform (over the complete set of generalized eigenfunctions defined naturally by the equilibrium). Details of the structure of the function space and the associated spectra are elucidated. Features of the (global) dispersion relation owing to the presence of gyroelastic stabilization are revealed. An energy principle is developed to study the stability of the tubular screwpinch.

  14. Gyroelastic fluids

    International Nuclear Information System (INIS)

    Kerbel, G.D.

    1981-01-01

    A study is made of a scale model in three dimensions of a guiding center plasma within the purview of gyroelastic (also known as finite gyroradius-near theta pinch) magnetohydrodynamics. The (nonlinear) system sustains a particular symmetry called isorrhopy which permits the decoupling of fluid modes from drift modes. Isorrhopic equilibria are analyzed within the framework of geometrical optics resulting in (local) dispersion relations and ray constants. A general scheme is developed to evolve an arbitrary linear perturbation of a screwpinch equilibrium as an invertible integral transform (over the complete set of generalized eigenfunctions defined naturally by the equilibrium). Details of the structure of the function space and the associated spectra are elucidated. Features of the (global) dispersion relation owing to the presence of gyroelastic stabilization are revealed. An energy principle is developed to study the stability of the tubular screwpinch

  15. Uranium mill tailings remedial action project real estate management plan

    Energy Technology Data Exchange (ETDEWEB)

    1994-09-01

    This plan summarizes the real estate requirements of the US Department of Energy`s (DOE) Uranium Mill Tailings Action (UMTRA) Project, identifies the roles and responsibilities of project participants involved in real estate activities, and describes the approaches used for completing these requirements. This document is intended to serve as a practical guide for all project participants. It is intended to be consistent with all formal agreements, but if a conflict is identified, the formal agreements will take precedence.

  16. Soil Carbon 4 per mille

    Science.gov (United States)

    Minasny, Budiman; van Wesemael, Bas

    2017-04-01

    The '4 per mille Soils for Food Security and Climate' was launched at the COP21 aiming to increase global soil organic matter stocks by 4 per mille (or 0.4 %) per year as a compensation for the global emissions of greenhouse gases by anthropogenic sources. This paper surveyed the soil organic carbon (SOC) stock estimates and sequestration potentials from 20 regions in the world (New Zealand, Chile, South Africa, Australia, Tanzania, Indonesia, Kenya, Nigeria, India, China Taiwan, South Korea, China Mainland, United States of America, France, Canada, Belgium, England & Wales, Ireland, Scotland, and Russia) and asked whether the 4 per mille initiative is feasible. This study highlights region specific efforts and scopes for soil carbon sequestration. Reported soil C sequestration rates generally show that under best management practices, 4 per mille or even higher sequestration rates can be accomplished. High C sequestration rates (up to 10 per mille) can be achieved for soils with low initial SOC stock (topsoil less than 30 t C ha-1), and at the first twenty years after implementation of best management practices. In addition, areas that have reached equilibrium but not at their saturation level will not be able to further increase their sequestration. We found that most studies on SOC sequestration globally only consider topsoil (up to 0.3 m depth), as it is considered to be most affected by management techniques. The 4 per mille initiative was based on a blanket calculation of the whole global soil profile C stock, however the potential to increase SOC is mostly on managed agricultural lands. If we consider 4 per mille on global topsoil of agricultural land, SOC sequestration is about 3.6 Gt C per year, which effectively offset 40% of global anthropogenic greenhouse gas emissions. As a strategy for climate change mitigation, soil carbon sequestration buys time over the next ten to twenty years while other effective sequestration and low carbon technologies become

  17. Assessing the value of pulp mill biomass savings in a climate change conscious economy

    International Nuclear Information System (INIS)

    Adahl, Anders; Harvey, Simon; Berntsson, Thore

    2006-01-01

    Pulp mills use significant amounts of biofuels, both internal and purchased. Biofuels could contribute to reach greenhouse gas emission targets at competitive costs. Implementing process integration measures at a pulp mill in order to achieve pulp production with less use of energy (biofuels) has not only on-site consequences but also off-site consequences, such as substitution of fossil fuels elsewhere by the saved pulp mill biofuels, and less on-site electric power generation. In this paper a method, a linking model, is suggested to analyse pulp mill biofuel saving measures when carbon dioxide (CO 2 ) external costs are internalised. The linking model is based on equilibrium economics and links information from CO 2 constrained energy market future scenarios with process integration measures. Pulp mill economics and marginal energy market CO 2 response are identified. In an applied study, four process integration measures at a Swedish pulp mill were analysed using five energy market future scenarios emanating from a Nordic energy model. The investigated investment alternatives for biofuel savings all result in positive net annual savings, irrespectively of the scenario used. However, CO 2 emissions may increase or decrease depending on the future development of the Nordic energy market

  18. Integration of micro milling highspeed spindle on a microEDM-milling machine set-up

    DEFF Research Database (Denmark)

    De Grave, Arnaud; Hansen, Hans Nørgaard; Andolfatto, Loic

    2009-01-01

    In order to cope with repositioning errors and to combine the fast removal rate of micro milling with the precision and small feature size achievable with micro EDM milling, a hybrid micro-milling and micro-EDM milling centre was built and tested. The aim was to build an affordable set-up, easy...

  19. Simulations of intermediate-energy heavy-ion collisions within relativistic mean-field two-fluid model

    International Nuclear Information System (INIS)

    Ivanov, Y.B.; Russkikh, V.N.; Pokrovsky, Y.E. Kurchatov; Ivanov, Y.B.; Russkikh, V.N.; Polrovsky, Y.E.; Henning, P.A.; Henning, P.A.

    1995-01-01

    A three-dimensional realization of the relativistic mean-field 2-fluid model is described. The first results of analyzing the inclusive data on the yield of nuclear fragments and pions, as well as the Plastic-Ball rapidity distributions of nuclear fragments are presented. For comparison, the calculations within the conventional relativistic hydrodynamical model with the same mean fields are also performed. It is found that all the analysed observables, except the pion spectra, appeared to be fairly insensitive to the nuclear EOS. The sensitivity to the nuclear stopping power is slightly higher. The original sensitivity of the rapidity distributions to the stopping power is smeared out by the Plastic-Ball filter and selection criterion. Nevertheless, one can conclude that the stopping power induced by the Cugnon cross-sections is not quite sufficient for a more adequate reproduction of the experimental data. (authors)

  20. Cold distribution networks. Cold distribution by two-phase refrigerant fluid. Case of ice slurries; Reseaux de distribution de froid. Distribution de froid par fluide frigoporteur diphasique. Cas du coulis de glace stabilisee (2002 - 2004). Rapport final (1er juillet 2004). Programme energie. PRI 9.1

    Energy Technology Data Exchange (ETDEWEB)

    Lallemand, A. [Institut National des Sciences Appliquees (INSA), Centre de Thermique de Lyon (CETHIL), UMR 5008, 69 - Villeurbanne (France); Mercier, P. [CEA Grenoble, Groupement pour la Recherche sur les Echangeurs Thermiques (GRETH), 38 (France); Royon, L. [Paris-1 Univ., Lab. de Biorheologie et d' Hydrodynamique Physico-Chimique, 75 (France); Dumas, J.P. [L' Ecole Nationale Superieure en Genie des Technologies Industrielles, Lab. de Thermique Energetique et Procedes, 64 - Pau (France); Guilpart, J. [URGPAN/CEMAGRE, 33 - Bordeaux (France)

    2004-07-01

    This PRI aims to participate to the development of alternate solutions for refrigerant fluids, for the cold transport and more specially a two phase refrigerant fluid: the stabilized ice slurry. The research program presented three main axis: design, realization and characterization of stabilized ice slurry, experimental studies of transport and transfer properties, study of online measurement process of the solid content. A simulation has been realized to evaluate the energy efficiency of this refrigerant use. (A.L.B.)

  1. Machine Shop. Module 6: Milling. Instructor's Guide.

    Science.gov (United States)

    Walden, Charles H.

    This document consists of materials for a 12-unit course on the following topics: (1) introduction to milling; (2) structure and accessories; (3) safety and maintenance; (4) cutting-tool variables; (5) basic set-up activities; (6) squaring a workpiece; (7) hole-making operations; (8) form milling; (9) machining keyways; (10) milling angular…

  2. On deformations of Yang-Mills algebras

    OpenAIRE

    Movshev, M.

    2005-01-01

    This is a next paper from a sequel devoted to algebraic aspects of Yang-Mills theory. We undertake a study of deformation theory of Yang-Mills algebra YM - a ``universal solution'' of Yang-Mills equation. We compute (cyclic) (co)homology of YM.

  3. Ground beetle populations near a kraft mill

    Energy Technology Data Exchange (ETDEWEB)

    Freitag, R.; Hastings, L.; Mercer, W.R.; Smith, A.

    1973-02-01

    Twenty species of ground beetles (Family Carabidae) and one species of carrion beetle (Family Silphidae) were collected in six stations east of a kraft paper mill in Thunder Bay, Ontario, from May to August, 1971. The beetle population decreased markedly towards the mill. There was no apparent statistical difference in size variation of specimens near the mill and those further away.

  4. Understanding milling induced changes: Some results

    Indian Academy of Sciences (India)

    Unknown

    Milling is identified as one of the robust processing routes for synthesizing a variety of materials. Commonly applied to the materials in solid state, the most noticeable change with milling is the reduction in the particle size, generally to nanoscale. In addition to size refinement, milling has received wide acceptability due to its ...

  5. Soil carbon 4 per mille

    NARCIS (Netherlands)

    Mulder, V.L.

    2017-01-01

    The ‘4 per mille Soils for Food Security and Climate’ was launched at the COP21 with an aspiration to increase global soil organic matter stocks by 4 per 1000 (or 0.4 %) per year as a compensation for the global emissions of greenhouse gases by anthropogenic sources. This paper surveyed the soil

  6. Massive Yang-Mills fields

    NARCIS (Netherlands)

    Veltman, M.J.G.; Reiff, J.

    1969-01-01

    Two problems are studied in the paper: (i) the relation between Lagrangian and Feynman rules if the Lagrangian contains derivative couplings and/or vector meson fields and (ii) the behaviour of certain two closed loop diagrams in the perturbation theory of Yang-Mills fields. With respect to ( i ) .

  7. Semiclassical scattering in Yang-Mills theory

    International Nuclear Information System (INIS)

    Gould, T.M.; Poppitz, E.R.

    1994-01-01

    A classical solution to the Yang-Mills theory is given a semiclassical interpretation. The boundary value problem on a complex time contour which arises from the semiclassical approximation to multiparticle scattering amplitudes is reviewed and applied to the case of Yang-Mills theory. The solution describes a classically forbidden transition between states with a large average number of particles in the limit g→0. It dominates a transition probability with a semiclassical suppression factor equal to twice the action of the well-known BPST instanton. Hence, it is relevant to the problem of high-energy tunnelling. It describes transitions of unit topological charge for an appropriate time contour. Therefore, it may have a direct interpretation in terms of fermion-number violating processes in electroweak theory. The solution describes a transition between an initial state with parametrically fewer particles than the final state. Thus, it may be relevant to the study of semiclassical initial-state corrections in the limit of a small number of initial particles. The implications of these results for multiparticle production in electroweak theory are also discussed. (orig.)

  8. Local saw mills save Velky Krtis

    International Nuclear Information System (INIS)

    Haluza, I.

    2006-01-01

    After the Bana Dolina coal mine has received its last state subsidy, the only major employer in the region will be the PRP saw mill. The unemployment rate is very high in the Velky Krtis region over 25%. Several agricultural and food processing companies have gone bankrupt and the Bana Dolina mine today only employs around 200 people. Few new jobs have been created. So far only furniture manufacturers from the Swedish company, Furni Finish, have promised the town they will open a new plant, where they may employ around 150. Another potential investment to be made by a Spanish producer of light components is still under negotiation, stated the mayor of Velky Krtis, Jozef Sauver. Should the Spanish company decide to come to the region, about 100 people could find a job at the former Liaz production halls. Currently, PRP is the largest employer in the region. Over the last 7 years, its owners have invested over 60 mil. Sk (1.58 mil. EUR) in the saw mill. Now they are preparing an 80 mil. Sk (2.10 mil. EUR) investment. The new business would process timber waste that is currently sold to the chipboard producer, Bucina DDD. In the future, the material could be used to produce energy. The town council are considering the construction of a new wood-fired heat plant that would use timber waste bought from PRP. (author)

  9. Fluid Mechanics.

    Science.gov (United States)

    Drazin, Philip

    1987-01-01

    Outlines the contents of Volume II of "Principia" by Sir Isaac Newton. Reviews the contributions of subsequent scientists to the physics of fluid dynamics. Discusses the treatment of fluid mechanics in physics curricula. Highlights a few of the problems of modern research in fluid dynamics. Shows that problems still remain. (CW)

  10. Fluid Interfaces

    DEFF Research Database (Denmark)

    Hansen, Klaus Marius

    2001-01-01

    Fluid interaction, interaction by the user with the system that causes few breakdowns, is essential to many user interfaces. We present two concrete software systems that try to support fluid interaction for different work practices. Furthermore, we present specificity, generality, and minimality...... as design goals for fluid interfaces....

  11. Model Predictive Control of a Wave Energy Converter with Discrete Fluid Power Power Take-Off System

    DEFF Research Database (Denmark)

    Hansen, Anders Hedegaard; Asmussen, Magnus Færing; Bech, Michael Møller

    2018-01-01

    Wave power extraction algorithms for wave energy converters are normally designed without taking system losses into account leading to suboptimal power extraction. In the current work, a model predictive power extraction algorithm is designed for a discretized power take of system. It is shown ho...

  12. Effect of chromium and aluminum addition on anisotropic and microstructural characteristics of ball milled nanocrystalline iron

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Rajiv, E-mail: rajiv06484met@gmail.com [IITB-Monash Research Academy, Indian Institute of Technology Bombay, Powai, Mumbai 400076 (India); Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology Bombay, Powai, Mumbai 400076 (India); Department of Mechanical and Aerospace Engineering, Monash University, VIC 3800 Australia (Australia); Joardar, Joydip [International Advanced Research Centre for Powder Metallurgy and New Materials, Hyderabad (India); Singh Raman, R.K. [Department of Mechanical and Aerospace Engineering, Monash University, VIC 3800 Australia (Australia); Department of Chemical Engineering, Monash University, VIC 3800 Australia (Australia); Raja, V.S. [Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology Bombay, Powai, Mumbai 400076 (India); Joshi, S.V. [International Advanced Research Centre for Powder Metallurgy and New Materials, Hyderabad (India); Parida, S. [Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology Bombay, Powai, Mumbai 400076 (India)

    2016-06-25

    Prior studies on synthesis of nanocrystalline elements have discussed the effect of ball milling on lattice parameter, crystallite size, and micro-strain. For elemental milled powders, the anisotropic peak broadening does not change with increasing milling time. However, the effect of alloying addition on the anisotropic behavior of ball milled nanocrystalline powders remains an unexplored area. Here we report the effect of chromium and aluminum addition on the anisotropic behavior of iron in nanocrystalline Fe–20Cr–5Al (wt%) alloy powders synthesized by ball milling. The experimental results show that the anisotropic behavior of iron changes towards isotropic with milling. This change was also correlated to the theoretically calculated anisotropic factor from the change in elastic constant of iron due to milling. Addition of alloying elements exhibited a monotonic rise in the lattice parameter with crystallite size, which was attributed to the excess grain boundary interfacial energy and excess free volume at grain boundaries. Transmission electron microscopy image confirmed the crystallite size and nature of dislocation obtained using modified Williamson-Hall method. - Highlights: • Structural evolution in Fe–20Cr–5Al alloy during ball milling is reported. • Effect of alloying addition on the anisotropic behavior of iron was studied. • Agreement in anisotropic factor calculated theoretically and experimentally.

  13. Effects and mechanism of ball milling on torrefaction of pine sawdust.

    Science.gov (United States)

    Gong, Chunxiao; Huang, Jing; Feng, Chen; Wang, Guanghui; Tabil, Lope; Wang, Decheng

    2016-08-01

    The effects and mechanism of ball milling on the torrefaction process were studied. Ball- and hammer-milled (screen size 1mm) pine sawdust samples were torrefied at three temperatures (230, 260, and 290°C) and two durations (30 and 60min) to investigate into their torrefaction behavior and physicochemical properties. The results showed that, under identical torrefaction conditions, torrefied ball-milled pine sawdust had a higher carbon content and fixed carbon, and lower hydrogen and oxygen contents than torrefied hammer-milled pine sawdust. Torrefied ball-milled pine sawdust produced lower mass and energy yields, but higher heating values than torrefied hammer-milled pine sawdust. Ball milling destroyed the crystalline structure of cellulose and thus reduced the thermal stability of hemicellulose, cellulose, and lignin, causing them to degrade at relatively lower temperatures. In conclusion, biomass pretreated with a combination of ball milling and torrefaction has the potential to produce an alternative fuel to coal. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Domestic uranium mining and milling industry 1989

    International Nuclear Information System (INIS)

    1990-01-01

    Section 170B of the Atomic Energy Act of 1954, as amended by Public Law 97-415, requires that the Secretary of Energy submit to Congress an annual assessment of the viability of the domestic uranium mining and milling industry. The Energy Information Administration (EIA) of the Department of Energy (DOE) was assigned the responsibility to develop the criteria for use in estimating the viability of the industry. These criteria include four major attributes of industry viability - resource capability, supply response capability, financial capability, and import commitment dependency. Having established these criteria, the Secretary of Energy is required to monitor the industry and make an annual assessment of its viability for 1983 through 1992. The first six assessments were issued in the years 1984 through 1989 based on information available for 1983 through 1988, respectively. The current report provides the data and analyses, based on the information available through the end of the calendar year 1989, supporting the seventh annual assessment of the uranium industry's viability. It presents information on the four major attributes. Data on past and present industry behavior, as well as projections of the future status of the industry (assuming current market conditions), were used to examine the industry's ability to respond, over a 10-year period, to two hypothetical supply disruption scenarios. 20 figs., 23 tabs

  15. Numerical simulation of an advanced energy storage system using H{sub 2}O-LiBr as working fluid, Part 2: System simulation and analysis

    Energy Technology Data Exchange (ETDEWEB)

    Xu, S.M.; Xu, C.H.; Zhang, L. [R and D Lab of Refrigeration and Heat Pump Technology, Department of Power Engineering, Dalian University of Technology, Liao Ning, 116024 (China); Liang, J.; Du, R. [Department of Automation and Computer-Aided Engineering, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong (China)

    2007-03-15

    This paper is the second part of our study on the advanced energy storage system using H{sub 2}O-LiBr as working fluid. In the first part, the system working principle has been introduced, and the system dynamic models in the operation process have also been developed. Based on the previous research, this paper focuses on the numerical simulation to investigate the system dynamic characteristics and performances when it works to provide combined air-conditioning and hot water supplying for a hotel located near by Yangzi River in China. The system operation conditions were set as follows: the outdoor temperature was between 29 C and 38 C, the maximum air-conditioning load was 1450 kW, the total air-conditioning capacity was 19,890 kWh and the 50 C hot water capacity for showering was 20 tons which needed heat about 721 kWh on a given day. Under these conditions, the system operation characteristics were simulated under the full- and partial-storage strategies. The simulation results predicted the dynamic characteristics and performances of the system, including the temperature and concentration of the working fluid, the mass and energy in the storage tanks, the compressor intake mass or volume flow rate, discharge pressure, compression ratio, power and consumption work, the heat loads of heat exchanger devices in the system and so on. The results also showed that the integrated coefficient of performances (COP{sub int}) of the system were 3.09 and 3.26, respectively, under the two storage strategies while the isentropic efficiency of water vapor compressor was 0.6. The simulation results are very helpful for understanding and evaluating the system as well as for system design, operation and control, and device design or selection in detail. (author)

  16. analysis of gear milling at vari gear milling at various gear milling

    African Journals Online (AJOL)

    eobe

    f), gave coefficients β0, β1 and β2 as 0.281, being significant to the adopted model and ignificant to .... roughness and tool wear in the cases of both hot and room temperature machining. Alberti, et al. [9] developed ... machining processes in milling operations, a reduction in processing times for both conventional and high.

  17. Influence of milling process on efavirenz solubility

    Directory of Open Access Journals (Sweden)

    Erizal Zaini

    2017-01-01

    Full Text Available Introduction: The aim of this study was to investigate the influence of the milling process on the solubility of efavirenz. Materials and Methods: Milling process was done using Nanomilling for 30, 60, and 180 min. Intact and milled efavirenz were characterized by powder X-ray diffraction, scanning electron microscopy (SEM, spectroscopy infrared (IR, differential scanning calorimetry (DSC, and solubility test. Results: The X-ray diffractogram showed a decline on peak intensity of milled efavirenz compared to intact efavirenz. The SEM graph depicted the change from crystalline to amorphous habit after milling process. The IR spectrum showed there was no difference between intact and milled efavirenz. Thermal analysis which performed by DSC showed a reduction on endothermic peak after milling process which related to decreasing of crystallinity. Solubility test of intact and milled efavirenz was conducted in distilled water free CO2with 0.25% sodium lauryl sulfate media and measured using high-performance liquid chromatography method with acetonitrile: distilled water (80:20 as mobile phases. The solubility was significantly increased (P < 0.05 after milling processes, which the intact efavirenz was 27.12 ± 2.05, while the milled efavirenz for 30, 60, and 180 min were 75.53 ± 1.59, 82.34 ± 1.23, and 104.75 ± 0.96 μg/mL, respectively. Conclusions: Based on the results, the solubility of efavirenz improved after milling process.

  18. On the energy inequality for weak solutions to the Navier-Stokes equations of compressible fluids on unbounded domains

    Czech Academy of Sciences Publication Activity Database

    Dell'Oro, Filippo; Feireisl, Eduard

    2015-01-01

    Roč. 128, November (2015), s. 136-148 ISSN 0362-546X R&D Projects: GA ČR GA13-00522S Institutional support: RVO:67985840 Keywords : compressible Navier - Stokes equations * unbounded domain * weak solutions * energy inequality Subject RIV: BA - General Mathematics Impact factor: 1.125, year: 2015 http://www.sciencedirect.com/science/article/pii/S0362546X15002692

  19. On the energy inequality for weak solutions to the Navier-Stokes equations of compressible fluids on unbounded domains

    Czech Academy of Sciences Publication Activity Database

    Dell'Oro, Filippo; Feireisl, Eduard

    2015-01-01

    Roč. 128, November (2015), s. 136-148 ISSN 0362-546X R&D Projects: GA ČR GA13-00522S Institutional support: RVO:67985840 Keywords : compressible Navier-Stokes equations * unbounded domain * weak solutions * energy inequality Subject RIV: BA - General Mathematics Impact factor: 1.125, year: 2015 http://www.sciencedirect.com/science/article/pii/S0362546X15002692

  20. Fluid dynamics of dilatant fluid

    DEFF Research Database (Denmark)

    Nakanishi, Hiizu; Nagahiro, Shin-ichiro; Mitarai, Namiko

    2012-01-01

    A dense mixture of granules and liquid often shows a severe shear thickening and is called a dilatant fluid. We construct a fluid dynamics model for the dilatant fluid by introducing a phenomenological state variable for a local state of dispersed particles. With simple assumptions for an equation...

  1. FePt magnetic particles prepared by surfactant-assisted ball milling

    Energy Technology Data Exchange (ETDEWEB)

    Velasco, V., E-mail: vvjimeno@fis.ucm.es [Instituto de Magnetismo Aplicado, UCM-ADIF-CSIC, P.O. Box 155, Las Rozas 28230 (Spain); Departamento de Física de Materiales, Universidad Complutense de Madrid, Madrid 28040 (Spain); Hernando, A.; Crespo, P. [Instituto de Magnetismo Aplicado, UCM-ADIF-CSIC, P.O. Box 155, Las Rozas 28230 (Spain); Departamento de Física de Materiales, Universidad Complutense de Madrid, Madrid 28040 (Spain)

    2013-10-15

    High-energy ball milling of Fe and Pt elemental powders has been carried out under dry and wet (in presence of solvent and surfactants) conditions. Dry milling leads to the formation of the disordered FCC-FePt alloy whereas by the wet milling procedure the main process is the decrease of Fe and Pt particle size, although some dissolution of Pt into Fe grains cannot be ruled out, and no hint of the formation of the FCC-FePt phase is observed even to milling times up to 20 h, as X-ray diffraction, electron microscopy and Mössbauer spectroscopy indicates. The as-milled particles were annealed at 600 °C for 2 h under Ar atmosphere. It is noticed that the disordered fcc-FePt phase observed in particles milled under dry conditions transform to ordered fct phase characterized by a hard magnetic behavior with a coercive field up to 10,000 Oe. However, those particles milled in the surfactant/solvent medium exhibit a soft magnetic behavior with a coercive field of 600 Oe. These results indicate that wet high-energy ball milling is not an adequate technique for obtaining single-phase FePt particles. - Highlights: • FePt particles have been obtained by high-energy ball milling. • In the presence of surfactants and solvents, almost no alloying process takes place. • After annealing, the coercive field of the FePt alloy particles increases from 150 Oe to 10,000 Oe.

  2. Formation of a 25 mol% Fe2O3-Al2O3 solid solution prepared by ball milling

    DEFF Research Database (Denmark)

    Jiang, Jianzhong; Mørup, Steen; Linderoth, Søren

    1996-01-01

    The phase transformation process of a 25 mol% Fe2O3-Al2O3 powder mixture during high-energy ball milling has been studied by x-ray diffraction and Mossbauer spectroscopy. A metastable solid solution of 25 mol % Fe2O3 in Al2O3 with corundum structure has successfully been prepared after a milling...

  3. Understanding Biomass Ignition in Power Plant Mills

    DEFF Research Database (Denmark)

    Schwarzer, Lars; Jensen, Peter Arendt; Glarborg, Peter

    2017-01-01

    % oxygen with those under inert atmosphere revealed two distinct pathways, pyrolysis and exothermic heterogeneous oxidation. At low temperatures and sufficient oxygen availability, heterogeneous oxidation of the solid seems to be favored over pyrolysis for wood, but not for coal. Current ignition models do......Converting existing coal fired power plants to biomass is a readily implemented strategy to increase the share of renewable energy. However, changing from one fuel to another is not straightforward: Experience shows that wood pellets ignite more readily than coal in power plant mills or storages....... This is not very well explained by apply-ing conventional thermal ignition theory. An experimental study at lab scale, using pinewood as an example fuel, was conducted to examine self-heating and self-ignition. Supplemental experiments were performed with bituminous coal. Instead of characterizing ignition...

  4. Uranium Mill Tailings Remedial Action Project, Surface Project Management Plan. Revision 1

    International Nuclear Information System (INIS)

    1994-12-01

    Title I of the Uranium Mill Tailings Radiation Control Act (UMTRCA) authorizes the US Department of Energy (DOE) to undertake remedial action at 24 designated inactive uranium processing sites and associated vicinity properties (VP) containing uranium mill tailings and related residual radioactive materials. The purpose of the Uranium Mill Tailings Remedial Action (UMTRA) Surface Project is to minimize or eliminate radiation health hazards to the public and the environment at the 24 sites and related VPs. This document describes the management organization, system, and methods used to manage the design, construction, and other activities required to clean up the designated sites and associated VPs, in accordance with the UMTRCA

  5. Covariant Canonical Method for Yang-Mills Theory Expressed as a Constrained BF-Like Theory

    OpenAIRE

    Escalante, Alberto; García, Irving

    2012-01-01

    The covariant canonical analysis for Yang-Mills theory expressed as a BF-like action is performed. We study a BF-like action, that in spite of being the coupling of two topological terms, yield, on shell to Yang-Mills action. In addition, by using the results obtained in the covariant canonical approach we study the symmetries of the action, in particular we calculate its energy-momentum tensor obtaining the same tensor found for Yang-Mills theory; then we confirm those results by using Noeth...

  6. Covariant Canonical Method for Yang-Mills Theory Expressed as a Constrained BF-Like Theory

    Directory of Open Access Journals (Sweden)

    Alberto Escalante

    2012-01-01

    Full Text Available The covariant canonical analysis for Yang-Mills theory expressed as a BF-like action is performed. We study a BF-like action, that in spite of being the coupling of two topological terms, yield, on shell to Yang-Mills action. In addition, by using the results obtained in the covariant canonical approach we study the symmetries of the action, in particular we calculate its energy-momentum tensor obtaining the same tensor found for Yang-Mills theory; then we confirm those results by using Noether's theorem.

  7. Fluids engineering

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    Fluids engineering has played an important role in many applications, from ancient flood control to the design of high-speed compact turbomachinery. New applications of fluids engineering, such as in high-technology materials processing, biotechnology, and advanced combustion systems, have kept up unwaining interest in the subject. More accurate and sophisticated computational and measurement techniques are also constantly being developed and refined. On a more fundamental level, nonlinear dynamics and chaotic behavior of fluid flow are no longer an intellectual curiosity and fluid engineers are increasingly interested in finding practical applications for these emerging sciences. Applications of fluid technology to new areas, as well as the need to improve the design and to enhance the flexibility and reliability of flow-related machines and devices will continue to spur interest in fluids engineering. The objectives of the present seminar were: to exchange current information on arts, science, and technology of fluids engineering; to promote scientific cooperation between the fluids engineering communities of both nations, and to provide an opportunity for the participants and their colleagues to explore possible joint research programs in topics of high priority and mutual interest to both countries. The Seminar provided an excellent forum for reviewing the current state and future needs of fluids engineering for the two nations. With the Seminar ear-marking the first formal scientific exchange between Korea and the United States in the area of fluids engineering, the scope was deliberately left broad and general

  8. Characterization of Al{sub 2}O{sub 3}NP-Al{sub 2024} and Ag{sub C}NP-Al{sub 2024} composites prepared by mechanical processing in a high energy ball mill

    Energy Technology Data Exchange (ETDEWEB)

    Carreno-Gallardo, C. [Centro de Investigacion en Materiales Avanzados (CIMAV), Laboratorio Nacional de Nanotecnologia-Chihuahua, Miguel de Cervantes No. 120, C.P. 31109, Chihuahua (Mexico); Universidad Autonoma Metropolitana, Departamento de Materiales, Av. San Pablo No. 180, Col Reynosa-Tamaulipas, CP 02200, D.F. (Mexico); Estrada-Guel, I. [Centro de Investigacion en Materiales Avanzados (CIMAV), Laboratorio Nacional de Nanotecnologia-Chihuahua, Miguel de Cervantes No. 120, C.P. 31109, Chihuahua (Mexico); Romero-Romo, M. [Universidad Autonoma Metropolitana, Departamento de Materiales, Av. San Pablo No. 180, Col Reynosa-Tamaulipas, CP 02200, D.F. (Mexico); Cruz-Garcia, R. [Universidad Autonoma de Chihuahua (UACH), Facultad de Ingenieria, Circuito No. 1 Nuevo Campus Universitario, C.P. 31125, Chihuahua (Mexico); Lopez-Melendez, C. [Centro de Investigacion en Materiales Avanzados (CIMAV), Laboratorio Nacional de Nanotecnologia-Chihuahua, Miguel de Cervantes No. 120, C.P. 31109, Chihuahua (Mexico); Universidad La Salle Chihuahua, Prol. Lomas de Majalca No. 11201, C.P. 31020, Chihuahua (Mexico); Martinez-Sanchez, R., E-mail: roberto.martinez@cimav.edu.mx [Centro de Investigacion en Materiales Avanzados (CIMAV), Laboratorio Nacional de Nanotecnologia-Chihuahua, Miguel de Cervantes No. 120, C.P. 31109, Chihuahua (Mexico)

    2012-09-25

    Graphical abstract: Mechanical alloying was used to produce two kinds of metal matrix composites based on 2024 aluminum alloy, the nanocomposites were reinforced with different percentages of Al{sub 2}O{sub 3} and Ag{sub C} nanoparticles. The content of nanoparticles has a role important on the mechanical properties of the nanocomposite. 10 h of milling time are enough to former the Al{sub 2024} nanocomposites. The results obtained by differential scanning calorimeter show the temperatures of intermetallic precipitation, which were identified by X-ray diffraction. The results revealed that mechanical alloying is an excellent route to incorporate and distribute NP into Al{sub 2024}. Highlights: Black-Right-Pointing-Pointer Aluminum-based nanocomposites were synthesized bay milling process. Black-Right-Pointing-Pointer An homogeneous nanoparticles dispersion was reached and mechanical properties were enhanced. Black-Right-Pointing-Pointer Phase transformation during heating was characterized by XRD. - Abstract: Mechanical alloying was used to produce two kinds of metal matrix composites based on 2024 aluminum alloy. The nanocomposites were reinforced with different percentages of Al{sub 2}O{sub 3} and Ag{sub C} nanoparticles. The content of nanoparticles has an important role on the mechanical properties of the nanocomposites. A milling time of 10 h is enough to form the Al{sub 2024} nanocomposites. The thermograms obtained by differential scanning calorimeter show the temperatures of phase precipitation, which were identified by X-ray diffraction. The results revealed that mechanical alloying is an excellent route for the incorporation and distribution of nanoparticles into Al{sub 2024}.

  9. Programação estocástica robusta aplicada ao planejamento agregado de safra em usinas cooperadas do setor sucroenergético Stochastic robust optimization model applied to the aggregate production planning in mill cooperative socities in the sugar-energy sector

    Directory of Open Access Journals (Sweden)

    Rafael Piatti Oiticica de Paiva

    2011-01-01

    Full Text Available Neste trabalho, apresenta-se um modelo de programação estocástica robusta aplicado ao planejamento agregado da produção em usinas cooperadas do setor sucroenergético. Esta modelagem considera a relação hierárquica existente entre o planejamento anual da cooperativa e o planejamento tático de safra das usinas cooperadas, além de contemplar importantes incertezas existentes nos parâmetros de entrada do modelo. Para resolver os problemas de programação linear e programação inteira mista envolvidos, utiliza-se uma linguagem de modelagem algébrica e um software de última geração de programação matemática. Os resultados computacionais obtidos são comparados aos resultados da modelagem determinística PASUC, discutida em Paiva e Morabito (in press, utilizando os mesmos dados do estudo de caso da Usina Santa Clotilde e da Cooperativa Regional dos Produtores de Açúcar e Álcool de Alagoas.This work presents a stochastic robust optimization model applied to the aggregate production planning in mill cooperative societies in the sugar-energy sector This mathematical model is based on a hierarchical relationship between the annual planning of the cooperative and the tactical planning horizon of the sugarcane mills taking into account important uncertainties in several parameters of this model. In order to solve the linear and mixed integer programming problems involved, an optimization modeling language solver was used. Computational results are presented and compared with the deterministic approach PASUC, dicussed by Paiva e Morabito (in press using the same data from the case studies conducted in the Santa Clotilde milling company and in the regional cooperative society of sugar and ethanol producers of Alagoas.

  10. Soil carbon 4 per mille

    OpenAIRE

    Minasny, B.; Malone, B. P.; McBratney, A. B.; Angers, D. A.; Arrouays, D.; Chambers, A.; Chaplot, Vincent; Chen, Z. S.; Cheng, K.; Das, B. S.; Field, D. J.; Gimona, A.; Hedley, C. B.; Hong, S. Y.; Mandal, B.

    2017-01-01

    The '4 per mille Soils for Food Security and Climate' was launched at the COP21 with an aspiration to increase global soil organic matter stocks by 4 per 1000 (or 0.4 %) per year as a compensation for the global emissions of greenhouse gases by anthropogenic sources. This paper surveyed the soil organic carbon (SOC) stock estimates and sequestration potentials from 20 regions in the world (New Zealand, Chile, South Africa, Australia, Tanzania, Indonesia, Kenya, Nigeria, India, China Taiwan, S...

  11. Rolling Mill Hill, Nashville, TN

    Science.gov (United States)

    Rolling Mill Hill was the home to Nashville General Hospital from 1890 to the 1990s and encompassed several buildings and structures. These existing buildings of historical significance were re-used in the form of apartments. The original Trolley Barns on the site are now artists’ lofts and are home to several companies and non-profit offices. Nance Place, which entails additional buildings built on-site, is a Tax Credit Workforce Housing Development and is Platinum LEED certified.

  12. Energie nécessaire au broyage de la biomasse et des produits densifiés

    Directory of Open Access Journals (Sweden)

    Temmerman, M.

    2011-01-01

    Full Text Available Milling energy needs for biomass and densified products. The literature about energy requirements for product milling in mining industry shows the subject has been, and still is, considered by numerous authors. Several milling theories have been proposed for these industries, especially concerning ores milling. The main mining milling theories and some of their evolutions are described in this paper. Biomass milling has been, by far, less studied. Nevertheless, few measurements are available about energy needed for milling of particular biomass, in particular systems. But studies taking into account enough characteristics of the milled material (origin, moisture content, particle size distribution are scarce. In consequence, nearly none biomass milling model has been proposed. Concerning densified products (pellets and briquettes apparently no data are available yet. Considering the milling theories, this study selects parameters that have to be taken into account when milling modeling comes to an end for biomass or densified biomass.

  13. Selective filling of photonic crystal fibers using focused ion beam milled microchannels

    DEFF Research Database (Denmark)

    Wang, Fei; Yuan, Scott Wu; Hansen, Ole

    2011-01-01

    We introduce a versatile, robust, and integrated technique to selectively fill fluid into a desired pattern of air holes in a photonic crystal fiber (PCF). Focused ion beam (FIB) is used to efficiently mill a microchannel on the end facet of a PCF before it is spliced to a single-mode fiber (SMF)......). Selected air holes are therefore exposed to the atmosphere through the microchannel for fluid filling. A low-loss in-line tunable optical hybrid fiber device is demonstrated by using such a technique. (C) 2011 Optical Society of America......We introduce a versatile, robust, and integrated technique to selectively fill fluid into a desired pattern of air holes in a photonic crystal fiber (PCF). Focused ion beam (FIB) is used to efficiently mill a microchannel on the end facet of a PCF before it is spliced to a single-mode fiber (SMF...

  14. Observer Based Fault Detection and Moisture Estimating in Coal Mill

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Mataji, Babak

    2008-01-01

    In this paper an observer-based method for detecting faults and estimating moisture content in the coal in coal mills is presented. Handling of faults and operation under special conditions, such as high moisture content in the coal, are of growing importance due to the increasing...... requirements to the general performance of power plants. Detection  of faults and moisture content estimation are consequently of high interest in the handling of the problems caused by faults and moisture content. The coal flow out of the mill is the obvious variable to monitor, when detecting non-intended drops in the coal...... flow out of the coal mill. However, this variable is not measurable. Another estimated variable is the moisture content, which is only "measurable" during steady-state operations of the coal mill. Instead, this paper suggests a method where these unknown variables are estimated based on a simple energy...

  15. Future CO2 removal from pulp mills - Process integration consequences

    International Nuclear Information System (INIS)

    Hektor, Erik; Berntsson, Thore

    2007-01-01

    Earlier work has shown that capturing the CO 2 from flue gases in the recovery boiler at a pulp mill can be a cost-effective way of reducing mill CO 2 emissions. However, the CO 2 capture cost is very dependent on the fuel price. In this paper, the potential for reducing the need for external fuel and thereby the possibility to reduce the cost for capturing the CO 2 are investigated. The reduction is achieved by using thermal process integration. In alternative 1, the mill processes are integrated and a steam surplus made available for CO 2 capture, but still there is a need for external fuel. In alternative 2, the integration is taken one step further, the reboiler is fed with MP steam, and the heat of absorption from the absorption unit is used for generation of LP steam needed at the mill. The avoidance costs are in both cases lower than before the process integration. The avoidance cost in alternative 1 varies between 25.4 and 30.7 EUR/tonne CO 2 depending on the energy market parameters. For alternative 2, the cost varies between 22.5 and 27.2 EUR/tonne CO 2 . With tough CO 2 reduction targets and correspondingly high CO 2 emission costs, the annual earnings can be substantial, 18.6 MEUR with alternative 1 and 21.2 MEUR with alternative 2

  16. A-TOUGH: A multimedia fluid-flow/energy-transport model for fully- coupled atmospheric-subsurface interactions

    International Nuclear Information System (INIS)

    Montazer, P.; Hammermeister, D.; Ginanni, J.

    1994-01-01

    The long-term effect of changes in atmospheric climatological conditions on subsurface hydrological conditions in the unsaturated zone in and environments is an important factor in defining the performance of a high-level and low-level radioactive waste repositories in geological environment. Computer simulation coupled with paleohydrological studies can be used to understand and quantify the potential impact of future climatological conditions on repository performance. A-TOUGH efficiently simulates (given current state-of-the-art technology) the physical processes involved in the near-surface atmosphere and its effect on subsurface conditions. This efficiency is due to the numerical techniques used in TOUGH and the efficient computational techniques used in V-TOUGH to solve non-linear thermodynamic equations that govern the flux of vapor and energy within subsurface porous and fractured media and between these media and the atmosphere

  17. Numerical analysis of fluid flow and heat transfer during melting inside a cylindrical container for thermal energy storage system

    Science.gov (United States)

    Bellan, Selvan; Cheok, Cho Hyun; Gokon, Nobuyuki; Matsubara, Koji; Kodama, Tatsuya

    2017-06-01

    This paper presents a numerical analysis of unconstrained melting of high temperature(>1000K) phase change material (PCM) inside a cylindrical container. Sodium chloride and Silicon carbide have been used as phase change material and shell of the capsule respectively. The control volume discretization approach has been used to solve the conservation equations of mass, momentum and energy. The enthalpy-porosity method has been used to track the solid-liquid interface of the PCM during melting process. Transient numerical simulations have been performed in order to study the influence of radius of the capsule and the Stefan number on the heat transfer rate. The simulation results show that the counter-clockwise Buoyancy driven convection over the top part of the solid PCM enhances the melting rate quite faster than the bottom part.

  18. On classical Yang-Mills equations with weak external sources

    International Nuclear Information System (INIS)

    Arodz, H.

    1982-05-01

    A method proposed by Jackiw, Jacobs and Rebbi for solving classical Yang-Mills equations with external color charges by an expansion of solution in powers of the external color charge is applied in order to find gauge potentials generated by the external color charge with Hopf index +-1. This topologically non-trivial charge turns out to support non-Abelian Coulomb type solution. A gauge invariant expression for energy in the presence of external currents is also proposed. (Auth.)

  19. Biogeochemistry of uranium mill wastes program overview and conclusions

    International Nuclear Information System (INIS)

    Dreesen, D.R.

    1981-05-01

    The major findings and conclusions are summarized for research on uranium mill tailings for the US Department of Energy and the US Nuclear Regulatory Commission. An overview of results and interpretations is presented for investigations of 222 Rn emissions, revegetation of tailings and mine spoils, and trace element enrichment, mobility, and bioavailability. A brief discussion addresses the implications of these findings in relation to tailings disposal technology and proposed uranium recovery processes

  20. Uranium mill tailings remedial action project real estate management plan

    International Nuclear Information System (INIS)

    1994-09-01

    This plan summarizes the real estate requirements of the US Department of Energy's (DOE) Uranium Mill Tailings Action (UMTRA) Project, identifies the roles and responsibilities of project participants involved in real estate activities, and describes the approaches used for completing these requirements. This document is intended to serve as a practical guide for all project participants. It is intended to be consistent with all formal agreements, but if a conflict is identified, the formal agreements will take precedence

  1. Wormhole instanton solution in the Einstein-Yang-Mills system

    International Nuclear Information System (INIS)

    Hosoya, Akio; Ogura, Waichi.

    1989-01-01

    A spherical symmetric classical solution of the Einstein and the SU(2) Yang-Mills equations is found in the four dimensional Euclidean space-time with the cosmological constant. The isospinor fermion has zero modes. Their cosmological implications are also discussed with an emphasis on the fact that wormhole instantons in general can be found not only in the sub-Planck physics but also in almost all the stages in lower energy physics. (author)

  2. Anaerobic digestion of pulp and paper mill wastewater and sludge.

    Science.gov (United States)

    Meyer, Torsten; Edwards, Elizabeth A

    2014-11-15

    Pulp and paper mills generate large amounts of waste organic matter that may be converted to renewable energy in form of methane. The anaerobic treatment of mill wastewater is widely accepted however, usually only applied to few selected streams. Chemical oxygen demand (COD) removal rates in full-scale reactors range between 30 and 90%, and methane yields are 0.30-0.40 m(3) kg(-1) COD removed. Highest COD removal rates are achieved with condensate streams from chemical pulping (75-90%) and paper mill effluents (60-80%). Numerous laboratory and pilot-scale studies have shown that, contrary to common perception, most other mill effluents are also to some extent anaerobically treatable. Even for difficult-to-digest streams such as bleaching effluents COD removal rates range between 15 and 90%, depending on the extent of dilution prior to anaerobic treatment, and the applied experimental setting. Co-digestion of different streams containing diverse substrate can level out and diminish toxicity, and may lead to a more robust microbial community. Furthermore, the microbial population has the ability to become acclimated and adapted to adverse conditions. Stress situations such as toxic shock loads or temporary organic overloading may be tolerated by an adapted community, whereas they could lead to process disturbance with an un-adapted community. Therefore, anaerobic treatment of wastewater containing elevated levels of inhibitors or toxicants should be initiated by an acclimation/adaptation period that can last between a few weeks and several months. In order to gain more insight into the underlying processes of microbial acclimation/adaptation and co-digestion, future research should focus on the relationship between wastewater composition, reactor operation and microbial community dynamics. The potential for engineering and managing the microbial resource is still largely untapped. Unlike in wastewater treatment, anaerobic digestion of mill biosludge (waste activated

  3. Influence of cation disorder on the magnetic properties of ball-milled ilmenite (FeTiO3)

    DEFF Research Database (Denmark)

    Mørup, Steen; Rasmussen, Helge Kildahl; Brok, Erik

    2012-01-01

    after high-energy ball-milling of up to 128 h, but neutron diffraction studies reveal significant cation redistribution of Fe2+ and Ti4+ ions in the ball-milled samples. Mössbauer spectroscopy studies show that the magnetic hyperfine field of Fe2+, which is around 5 T before ball-milling, increases......We have investigated the evolution of crystal structure, cation disorder and magnetic properties of ilmenite (FeTiO3) after increasing time of high-energy ball-milling in an inert atmosphere. Refinement of X-ray diffraction data show that the hexagonal crystal structure of ilmenite is maintained......-milled spinel ferrites, the Néel temperature of ilmenite is not significantly affected by the cation disorder....

  4. Simulation of fluid flow and energy transport processes associated with high-level radioactive waste disposal in unsaturated alluvium

    Science.gov (United States)

    Pollock, David W.

    1986-01-01

    Many parts of the Great Basin have thick zones of unsaturated alluvium which might be suitable for disposing of high-level radioactive wastes. A mathematical model accounting for the coupled transport of energy, water (vapor and liquid), and dry air was used to analyze one-dimensional, vertical transport above and below an areally extensive repository. Numerical simulations were conducted for a hypothetical repository containing spent nuclear fuel and located 100 m below land surface. Initial steady state downward water fluxes of zero (hydrostatic) and 0.0003 m yr−1were considered in an attempt to bracket the likely range in natural water flux. Predicted temperatures within the repository peaked after approximately 50 years and declined slowly thereafter in response to the decreasing intensity of the radioactive heat source. The alluvium near the repository experienced a cycle of drying and rewetting in both cases. The extent of the dry zone was strongly controlled by the mobility of liquid water near the repository under natural conditions. In the case of initial hydrostatic conditions, the dry zone extended approximately 10 m above and 15 m below the repository. For the case of a natural flux of 0.0003 m yr−1 the relative permeability of water near the repository was initially more than 30 times the value under hydrostatic conditions, consequently the dry zone extended only about 2 m above and 5 m below the repository. In both cases a significant perturbation in liquid saturation levels persisted for several hundred years. This analysis illustrates the extreme sensitivity of model predictions to initial conditions and parameters, such as relative permeability and moisture characteristic curves, that are often poorly known.

  5. Fluid transport due to nonlinear fluid-structure interaction

    DEFF Research Database (Denmark)

    Jensen, Jakob Søndergaard

    1997-01-01

    This work considers nonlinear fluid-structure interaction for a vibrating pipe containing fluid. Transverse pipe vibrations will force the fluid to move relative to the pipe creating unidirectional fluid flow towards the pipe end. The fluid flow induced affects the damping and the stiffness...... of the pipe. The behavior of the system in response to lateral resonant base excitation is analysed numerically and by the use of a perturbation method (multiple scales). Exciting the pipe in the fundamental mode of vibration seems to be most effective for transferring energy from the shaker to the fluid......, whereas higher modes of vibration can be used to transport fluid with pipe vibrations of smaller amplitude. The effect of the nonlinear geometrical terms is analysed and these terms are shown to affect the response for higher modes of vibration. Experimental investigations show good agreement...

  6. GEOMETRICAL CHARACTERIZATION OF MICRO END MILLING TOOLS

    DEFF Research Database (Denmark)

    Borsetto, Francesca; Bariani, Paolo

    /lubricants, milling strategies and controls. Moreover the accuracy of tool geometry directly affects the performance of the milling process influencing the dimensional tolerances of the machined part, the surface topography, the chip formation, the cutting forces and the tool-life. The dimensions of certain...... report is to develop procedures for the geometrical characterization of micro end milling tools in order to define a method suitable for the quality assurance in the micro cutting field....

  7. Mill, Liberty And The Facts Of Life

    OpenAIRE

    Stimson, Shannon C.; Milgate, Murray

    2001-01-01

    This paper examines John Stuart Mill's discussion of economic liberty and individual liberty, and his view of the relationship between the two. It explores how, and how effectively, Mill developed his arguments about the two liberties; reveals the lineages of thought from which they derived; and considers how his arguments were altered by political economists not long after his death. It is argued that the distinction Mill drew between the two liberties provided him with a framework of conc...

  8. Tooling Design of Milling Compounding Machine

    Directory of Open Access Journals (Sweden)

    Shan Wen Ju

    2016-01-01

    Full Text Available Professional tooling design is one of the most important part of the Milling Compounding Machine design. This paper mainly introduces the fundamental process of the tooling Design of Milling Compounding Machine, which includes the choosing of tooling material, the development and the chosen principle of tooling structure, the chosen principle of the milling cutters, and the geometry design of the cutters etc. it has certain significance for the practice production discussed.

  9. Schroedinger fluid

    International Nuclear Information System (INIS)

    Kan, K.K.

    1983-01-01

    The relationship of nuclear internal flow and collective inertia, the difference of this flow from that of a classical fluid, and the approach of this flow to rigid flow in independent-particle model rotation are elucidated by reviewing the theory of Schroedinger fluid and its implications for collective vibration and rotation. (author)

  10. Fluid Dynamics

    DEFF Research Database (Denmark)

    Brorsen, Michael

    These lecture notes are intended mainly for the 7th semester course "Fluid Dynamics" offered by the Study Committee on Civil Engineering, Aalborg University.......These lecture notes are intended mainly for the 7th semester course "Fluid Dynamics" offered by the Study Committee on Civil Engineering, Aalborg University....

  11. Microstructural Evolution, Thermodynamics, and Kinetics of Mo-Tm₂O₃ Powder Mixtures during Ball Milling.

    Science.gov (United States)

    Luo, Yong; Ran, Guang; Chen, Nanjun; Shen, Qiang; Zhang, Yaoli

    2016-10-15

    The microstructural evolution, thermodynamics, and kinetics of Mo (21 wt %) Tm₂O₃ powder mixtures during ball milling were investigated using X-ray diffraction and transmission electron microscopy. Ball milling induced Tm₂O₃ to be decomposed and then dissolved into Mo crystal. After 96 h of ball milling, Tm₂O₃ was dissolved completely and the supersaturated nanocrystalline solid solution of Mo (Tm, O) was obtained. The Mo lattice parameter increased with increasing ball-milling time, opposite for the Mo grain size. The size and lattice parameter of Mo grains was about 8 nm and 0.31564 nm after 96 h of ball milling, respectively. Ball milling induced the elements of Mo, Tm, and O to be distributed uniformly in the ball-milled particles. Based on the semi-experimental theory of Miedema, a thermodynamic model was developed to calculate the driving force of phase evolution. There was no chemical driving force to form a crystal solid solution of Tm atoms in Mo crystal or an amorphous phase because the Gibbs free energy for both processes was higher than zero. For Mo (21 wt %) Tm₂O₃, it was mechanical work, not the negative heat of mixing, which provided the driving force to form a supersaturated nanocrystalline Mo (Tm, O) solid solution.

  12. Comparison of wind mill cluster performance: A multicriteria approach

    Energy Technology Data Exchange (ETDEWEB)

    Rajakumar, D.G.; Nagesha, N. [Visvesvaraya Technological Univ., Karnataka (India)

    2012-07-01

    Energy is a crucial input for the economic and social development of any nation. Both renewable and non-renewable energy contribute in meeting the total requirement of the economy. As an affordable and clean energy source, wind energy is amongst the world's fastest growing renewable energy forms. Though there are several wind-mill clusters producing energy in different geographical locations, evaluating their performance is a complex task and not much of literature is available in this area. In this backdrop, an attempt is made in the current paper to estimate the performance of a wind-mill cluster through an index called Cluster Performance Index (CPI) adopting a multi-criteria approach. The proposed CPI comprises four criteria viz., Technical Performance Indicators (TePI), Economic Performance Indicators (EcPI), Environmental Performance Indicators (EnPI), and Sociological Performance Indicators (SoPI). Under each performance criterion a total of ten parameters are considered with five subjective and five objective oriented responses. The methodology is implemented by collecting empirical data from three wind-mill clusters located at Chitradurga, Davangere, and Gadag in the southern Indian State of Karnataka. Totally fifteen different stake holders are consulted through a set of structured researcher administered questionnaire to collect the relevant data in each wind farm. Stake holders involved engineers working in wind farms, wind farm developers, Government officials from energy department and a few selected residential people near the wind farms. The results of the study revealed that Chitradurga wind farm performed much better with a CPI of 45.267 as compared to Gadag (CPI of 28.362) and Davangere (CPI of 19.040) wind farms. (Author)

  13. CEE3500 - Fluid Mechanics, Spring 2006

    OpenAIRE

    Urroz, Gilberto E.

    2006-01-01

    Explores fluid properties, hydrostatics, fluid dynamics, similitude, energy and momentum principles, closed conduit flow, open channel flow, and flow measurement. Includes laboratory exercises in flow measurement, open channel flow, pipe friction, physical modeling, and data collection.

  14. Maximally Supersymmetric Yang-Mills Theory: The Story of N = 4 Yang-Mills Theory

    Science.gov (United States)

    Brink, Lars

    The following sections are included: * History * Dual Models * Supersymmetric Field Theories and Supergravity * Maximally Supersymmetric Yang-Mills Theories * The Light-Cone Gauge Formulation of N = 4 Yang-Mills Theory * The Perturbative Finiteness N = 4 Yang-Mills Theory * References

  15. Considerations Concerning the Dynamics of Vibratory Mills Used in Powders’ Mechanical Milling Process

    Directory of Open Access Journals (Sweden)

    Radu Panaitescu-Liess

    2010-01-01

    Full Text Available Dynamic mechanical milling process in a powder mill was studied by analyzing the vibratory effects of vibration and shock phenomena on the material microstructure ground. During the milling process, there were noticed both distinct modes of ball motion: the one generated by the periodic vibration and the one produced by chaotic vibration.

  16. Theoretical Exploration of Exponential Heat Source and Thermal Stratification Effects on The Motion of 3-Dimensional Flow of Casson Fluid Over a Low Heat Energy Surface at Initial Unsteady Stage

    Directory of Open Access Journals (Sweden)

    Sandeep N.

    2017-06-01

    Full Text Available Within the last few decades, experts and scientists dealing with the flow of non-Newtonian fluids (most especially Casson fluid have confirmed the existence of such flow on a stretchable surface with low heat energy (i.e. absolute zero of temperature. This article presents the motion of a three-dimensional of such fluid. Influence of uniform space dependent internal heat source on the intermolecular forces holding the molecules of Casson fluid is investigated. It is assumed that the stagnation flow was induced by an external force (pressure gradient together with impulsive. Based on these assumptions, variable thermophysical properties are most suitable; hence modified kinematic viscosity model is presented. The system of governing equations of 3-dimensional unsteady Casson fluid was non-dimensionalized using suitable similarity transformation which unravels the behavior of the flow at full fledge short period. The numerical solution of the corresponding boundary value problem (ODE was obtained using Runge-Kutta fourth order along with shooting technique. The intermolecular forces holding the molecules of Casson fluid flow in both horizontal directions when magnitude of velocity ratio parameters are greater than unity breaks continuously with an increase in Casson parameter and this leads to an increase in velocity profiles in both directions.

  17. Theoretical Exploration of Exponential Heat Source and Thermal Stratification Effects on The Motion of 3-Dimensional Flow of Casson Fluid Over a Low Heat Energy Surface at Initial Unsteady Stage

    Science.gov (United States)

    Sandeep, N.; Animasaun, I. L.

    2017-06-01

    Within the last few decades, experts and scientists dealing with the flow of non-Newtonian fluids (most especially Casson fluid) have confirmed the existence of such flow on a stretchable surface with low heat energy (i.e. absolute zero of temperature). This article presents the motion of a three-dimensional of such fluid. Influence of uniform space dependent internal heat source on the intermolecular forces holding the molecules of Casson fluid is investigated. It is assumed that the stagnation flow was induced by an external force (pressure gradient) together with impulsive. Based on these assumptions, variable thermophysical properties are most suitable; hence modified kinematic viscosity model is presented. The system of governing equations of 3-dimensional unsteady Casson fluid was non-dimensionalized using suitable similarity transformation which unravels the behavior of the flow at full fledge short period. The numerical solution of the corresponding boundary value problem (ODE) was obtained using Runge-Kutta fourth order along with shooting technique. The intermolecular forces holding the molecules of Casson fluid flow in both horizontal directions when magnitude of velocity ratio parameters are greater than unity breaks continuously with an increase in Casson parameter and this leads to an increase in velocity profiles in both directions.

  18. Rheology of Active Fluids

    Science.gov (United States)

    Saintillan, David

    2018-01-01

    An active fluid denotes a viscous suspension of particles, cells, or macromolecules able to convert chemical energy into mechanical work by generating stresses on the microscale. By virtue of this internal energy conversion, these systems display unusual macroscopic rheological signatures, including a curious transition to an apparent superfluid-like state where internal activity exactly compensates viscous dissipation. These behaviors are unlike those of classical complex fluids and result from the coupling of particle configurations with both externally applied flows and internally generated fluid disturbances. Focusing on the well-studied example of a suspension of microswimmers, this review summarizes recent experiments, models, and simulations in this area and highlights the critical role played by the rheological response of these active materials in a multitude of phenomena, from the enhanced transport of passive suspended objects to the emergence of spontaneous flows and collective motion.

  19. Transport of iron particles generated during milling operations in multilateral wells; Transporte de particulas de aco geradas pela abertura de janelas em pocos multilaterais

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Andre Leibsohn; Rezende, Carla Leonor Teixeira; Leal, Rafael Amorim Ferreira; Lourenco, Fabio Gustavo Fernandes [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas]. E-mail: aleibsohn@cenpes.petrobras.com.br; rezenc@hotmail.com; ramorim@cenpes.petrobras.com.br; fabiolou@urbi.com.br

    2000-07-01

    This paper presents a series of numerical simulations aimng the definition of requirements (flow rate and fluid properties) to remove iron particles both in the inclined sections and in the riser annulus. Additionally, experimental work was developed in a pilot scale flow loop in order tocompare the behavior of water and sinthetic oil baed fluids in milling operations. (author)

  20. Technology for Increasing Geothermal Energy Productivity. Computer Models to Characterize the Chemical Interactions of Goethermal Fluids and Injectates with Reservoir Rocks, Wells, Surface Equiptment

    Energy Technology Data Exchange (ETDEWEB)

    Nancy Moller Weare

    2006-07-25

    This final report describes the results of a research program we carried out over a five-year (3/1999-9/2004) period with funding from a Department of Energy geothermal FDP grant (DE-FG07-99ID13745) and from other agencies. The goal of research projects in this program were to develop modeling technologies that can increase the understanding of geothermal reservoir chemistry and chemistry-related energy production processes. The ability of computer models to handle many chemical variables and complex interactions makes them an essential tool for building a fundamental understanding of a wide variety of complex geothermal resource and production chemistry. With careful choice of methodology and parameterization, research objectives were to show that chemical models can correctly simulate behavior for the ranges of fluid compositions, formation minerals, temperature and pressure associated with present and near future geothermal systems as well as for the very high PT chemistry of deep resources that is intractable with traditional experimental methods. Our research results successfully met these objectives. We demonstrated that advances in physical chemistry theory can be used to accurately describe the thermodynamics of solid-liquid-gas systems via their free energies for wide ranges of composition (X), temperature and pressure. Eight articles on this work were published in peer-reviewed journals and in conference proceedings. Four are in preparation. Our work has been presented at many workshops and conferences. We also considerably improved our interactive web site (geotherm.ucsd.edu), which was in preliminary form prior to the grant. This site, which includes several model codes treating different XPT conditions, is an effective means to transfer our technologies and is used by the geothermal community and other researchers worldwide. Our models have wide application to many energy related and other important problems (e.g., scaling prediction in petroleum

  1. Technology for Increasing Geothermal Energy Productivity. Computer Models to Characterize the Chemical Interactions of Geothermal Fluids and Injectates with Reservoir Rocks, Wells, Surface Equipment

    International Nuclear Information System (INIS)

    Nancy Moller Weare

    2006-01-01

    This final report describes the results of a research program we carried out over a five-year (3/1999-9/2004) period with funding from a Department of Energy geothermal FDP grant (DE-FG07-99ID13745) and from other agencies. The goal of research projects in this program were to develop modeling technologies that can increase the understanding of geothermal reservoir chemistry and chemistry-related energy production processes. The ability of computer models to handle many chemical variables and complex interactions makes them an essential tool for building a fundamental understanding of a wide variety of complex geothermal resource and production chemistry. With careful choice of methodology and parameterization, research objectives were to show that chemical models can correctly simulate behavior for the ranges of fluid compositions, formation minerals, temperature and pressure associated with present and near future geothermal systems as well as for the very high PT chemistry of deep resources that is intractable with traditional experimental methods. Our research results successfully met these objectives. We demonstrated that advances in physical chemistry theory can be used to accurately describe the thermodynamics of solid-liquid-gas systems via their free energies for wide ranges of composition (X), temperature and pressure. Eight articles on this work were published in peer-reviewed journals and in conference proceedings. Four are in preparation. Our work has been presented at many workshops and conferences. We also considerably improved our interactive web site (geotherm.ucsd.edu), which was in preliminary form prior to the grant. This site, which includes several model codes treating different XPT conditions, is an effective means to transfer our technologies and is used by the geothermal community and other researchers worldwide. Our models have wide application to many energy related and other important problems (e.g., scaling prediction in petroleum

  2. HYDROCOIN [HYDROlogic COde INtercomparison] Level 1: Benchmarking and verification test results with CFEST [Coupled Fluid, Energy, and Solute Transport] code: Draft report

    International Nuclear Information System (INIS)

    Yabusaki, S.; Cole, C.; Monti, A.M.; Gupta, S.K.

    1987-04-01

    Part of the safety analysis is evaluating groundwater flow through the repository and the host rock to the accessible environment by developing mathematical or analytical models and numerical computer codes describing the flow mechanisms. This need led to the establishment of an international project called HYDROCOIN (HYDROlogic COde INtercomparison) organized by the Swedish Nuclear Power Inspectorate, a forum for discussing techniques and strategies in subsurface hydrologic modeling. The major objective of the present effort, HYDROCOIN Level 1, is determining the numerical accuracy of the computer codes. The definition of each case includes the input parameters, the governing equations, the output specifications, and the format. The Coupled Fluid, Energy, and Solute Transport (CFEST) code was applied to solve cases 1, 2, 4, 5, and 7; the Finite Element Three-Dimensional Groundwater (FE3DGW) Flow Model was used to solve case 6. Case 3 has been ignored because unsaturated flow is not pertinent to SRP. This report presents the Level 1 results furnished by the project teams. The numerical accuracy of the codes is determined by (1) comparing the computational results with analytical solutions for cases that have analytical solutions (namely cases 1 and 4), and (2) intercomparing results from codes for cases which do not have analytical solutions (cases 2, 5, 6, and 7). Cases 1, 2, 6, and 7 relate to flow analyses, whereas cases 4 and 5 require nonlinear solutions. 7 refs., 71 figs., 9 tabs

  3. Flight and Stability of a Laser Inertial Fusion Energy Target in the Drift Region between Injection and the Reaction Chamber with Computational Fluid Dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Mitori, T. [California Polytechnic State Univ. (CalPoly), San Luis Obispo, CA (United States)

    2013-12-01

    A Laser Inertial Fusion Energy (LIFE) target’s flight through a low Reynolds number and high Mach number regime was analyzed with computational fluid dynamics software. This regime consisted of xenon gas at 1,050 K and approximately 6,670 Pa. Simulations with similar flow conditions were performed with a sphere and compared with experimental data and published correlations for validation purposes. Transient considerations of the developing flow around the target were explored. Simulations of the target at different velocities were used to determine correlations for the drag coefficient and Nusselt number as functions of the Reynolds number. Simulations with different angles of attack were used to determine the aerodynamic coefficients of drag, lift, Magnus moment, and overturning moment as well as target stability. The drag force, lift force, and overturning moment changed minimally with spin. Above an angle of attack of 15°, the overturning moment would be destabilizing. At low angles of attack (less than 15°), the overturning moment would tend to decrease the target’s angle of attack, indicating the lack of a need for spin for stability at small angles. This stabilizing moment would cause the target to move in a mildly damped oscillation about the axis parallel to the free-stream velocity vector through the target’s center of gravity.

  4. Signatures of a new state of the nuclear matter: 'nearly perfect fluid of quarks and gluons' in heavy ion collisions at RHIC energies

    International Nuclear Information System (INIS)

    Nouicer, R.

    2013-01-01

    This thesis for the 'Accreditation to lead research' diploma consists of six chapters. Chapter I provides an overview of my scientific career, including a summary of my research tasks, professional experiences, and scientific output, list of my oral presentations at international conferences and my publications history. Chapter II introduces the background and goals of research in relativistic heavy ion physics, the main axis of research at the RHIC collider facility. Chapter III describes the context of Quarks-Gluon Plasma (QGP) physics including theoretical aspects, experimental aspects, the signatures of deconfinement and the evolution of QGP physics from fixed-target (SPS) to collider (RHIC) beam energies. Chapter IV details my personal contribution to the construction, assembly, installation, operation, evaluation of the signals and the maintenance of (i) the silicon pixel detectors used for the measurements of the charged particles multiplicity in PHOBOS experiment, and also (ii) the silicon vertex tracker (VTX) in PHENIX, with the main goal being to differentiate measurements of the heavy quarks charm and beauty. Chapter V presents my analysis work using the 'hit-counting' method which allows the measurement of the pseudorapidity density distributions of charged particles in PHOBOS at several RHIC energies. This chapter also illustrates my predictions for the LHC as well my publications as principal author and my responsibilities as 'Co-convenor' of the multiplicity group in PHOBOS. Finally, chapter VI presents the highlights of the RHIC results: 'Nearly Perfect Fluid of Quarks and Gluons'. This chapter illustrates a great wealth of scientific discoveries, and some great surprises encountered in the RHIC era which provided new perspectives in quantum chromodynamics (QCD) calculations. At the end of this chapter, I concluded while answering the question about what we have learnt and where we are. (author)

  5. Consolidation theory and its applicability to the dewatering and covering of uranium-mill tailings

    International Nuclear Information System (INIS)

    Gates, T.E.

    1982-11-01

    This report is a review and evaluation of soil consolidation theories applicable for evaluating settlement during dewatering and subsequent covering of uranium-mill tailings. Such theories may be used to predict both consolidation and water flow related effects in uranium-mill tailings during drainage, following sluicing into burial pits. A consolidation theory to be useful must consider the effect of time-dependent loads, nonhomogeneous soil mass, nonlinear variation of soil properties with the stress-state parameters, large strain, and saturated and unsaturated flow. Constitutive relations linking the stress-deformation-state variables with void ratio should be adopted for predicting both consolidation and fluid-flow interaction in unsaturated uranium-mill tailings

  6. KSC ADVANCED GROUND BASED FIELD MILL V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The Advanced Ground Based Field Mill (AGBFM) network consists of 34 (31 operational) field mills located at Kennedy Space Center (KSC), Florida. The field mills...

  7. NdFeB nanoparticles prepared by wet-milling

    Energy Technology Data Exchange (ETDEWEB)

    Thielsch, Juliane; Lyubina, Julia; Woodcock, Thomas; Schultz, Ludwig; Gutfleisch, Oliver [IFW Dresden (Germany)

    2010-07-01

    Since the prediction of a giant energy product of textured nanocomposite magnets those materials where believed to be the next generation of permanent magnets. For effective exchange-coupling in such two-phase magnets grain sizes need to be in the range of the domain wall width of the hard magnetic phase. That makes a homogenous phase distribution and a microstructure with nanograins necessary. One option of preparing such materials is the synthesis of magnetic nanoparticles which further could be aligned and compacted to a bulk magnet. For this we performed wet-milling experiments of a NdFeGaNbB alloy. XRD studies revealed that by using a surfactant and a solvent during the high energy ball milling process amorphization sets in later than compared to dry milling experiments under the same conditions. Dynamic Light Scattering investigations showed a Gauss distribution of the particle size with a mean diameter of about 12nm which was also proven by TEM. Magnetic properties were measured with SQUID and showed so far rather poor coercivity values.

  8. Towards the effective tool wear control in micro-EDM milling

    DEFF Research Database (Denmark)

    Bissacco, Giuliano; Valentincic, J.; Hansen, Hans Nørgaard

    2010-01-01

    The electrode wear in micro-electrical discharge milling (micro-EDM milling) is one of the main problems to be solved in order to improve machining accuracy. This paper presents an investigation on wear and material removal in micro-EDM milling for selected process parameter combinations typical...... of rough and finish machining of micro-features in steel. The experiments were performed on state-of-the-art micro-EDM equipment. Based on discharge counting and volume measurements, electrode wear per discharge and material removal per discharge were measured for several energy levels. The influence...... of the accuracy of volume measurements on the electrode wear per discharge and on the material removal per discharge are discussed, and the issues limiting the applicability of real time wear sensing in micro-EDM milling are presented....

  9. Processing of magnetically anisotropic MnBi particles by surfactant assisted ball milling

    Energy Technology Data Exchange (ETDEWEB)

    Kanari, K. [Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Sarafidis, C., E-mail: hsara@physics.auth.gr [Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Gjoka, M.; Niarchos, D. [INN, NCSR Demokritos, Athens 15310 (Greece); Kalogirou, O. [Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece)

    2017-03-15

    MnBi particles are obtained from bulk MnBi using mechanochemical processing. The structure and magnetic properties of the MnBi particles are investigated by means of X-ray diffraction analysis, scanning electron microscopy and magnetometry. Surfactant assisted high energy ball milling results to the samples’ degradation even after one hour of milling. In the case of surfactant assisted low energy ball milling the increase of ball milling duration decreases the average particle size while the particles seem to be more separated. The saturation magnetization (M{sub s}) was found to decrease for large milling times beginning from 61 Am{sup 2}/kg, while the coercivity (μ{sub 0}H{sub c}) increases with the increase of ball milling duration up to 35 min where it reaches 1.62 T and thereafter it decreases. - Highlights: • Effect of surfactants in processing of MnBi. • Magnetization degradation due to air storage and due to processing. • Coercivity of 1.6 T in epoxy resin oriented material.

  10. Environmental activities in uranium mining and milling. A Joint NEA/IAEA report

    International Nuclear Information System (INIS)

    1999-01-01

    This report on 'Environmental Activities in Uranium Mining and Milling' presents an overview of environmental activities related to uranium production. The profile of activities and concerns are based on survey responses from 29 countries and a review of relevant activities of the International Atomic Energy Agency and the OECD Nuclear Energy Agency. It also provides an overview of the reported interests of specialists working in the field, including environmental impact assessment, emissions to air and water, work environment, radiation safety, waste handling and disposal, mine and mill decommissioning and site restoration, and the regulation of these activities. The report reflects the increasing awareness in all countries of the need for environmental protection. For several years large programmes have been underway in several countries to clean up wastes from closed mines and mills. Many of these sites, particularly the older ones, were brought into production, operated and closed when little was known about environmental effects. At the time, little concern was given to the resulting environmental impacts. Currently, planning for and conducting uranium mine closure and mill decommissioning, together with site clean-up and restoration, are of almost universal concern. Mine closure and mill decommissioning activities have been or are being conducted in most of the countries with a history of uranium production. Information about several mine closures and mill decommissioning projects is included in this report

  11. Energy

    International Nuclear Information System (INIS)

    Meister, F.; Ott, F.

    2002-01-01

    This chapter gives an overview of the current energy economy in Austria. The Austrian political aims of sustainable development and climate protection imply a reorientation of the Austrian energy policy as a whole. Energy consumption trends (1993-1998), final energy consumption by energy carrier (indexed data 1993-1999), comparative analysis of useful energy demand (1993 and 1999) and final energy consumption of renewable energy sources by sector (1996-1999) in Austria are given. The necessary measures to be taken in order to reduce the energy demand and increased the use of renewable energy are briefly mentioned. Figs. 5. (nevyjel)

  12. Coexistence of short- and long-range ferromagnetic order in nanocrystalline Fe{sub 2}Mn{sub 1−x}Cu{sub x}Al (x=0.0, 0.1 and 0.3) synthesized by high-energy ball milling

    Energy Technology Data Exchange (ETDEWEB)

    Thanh, Tran Dang, E-mail: thanhxraylab@yahoo.com [Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Hanoi (Viet Nam); Nanto, Dwi [Physics Education, Syarif Hidayatullah States Islamic University, Jakarta 15412 (Indonesia); Tuyen, Ngo Thi Uyen [Department of Natural Science, Nha Trang Pedagogic College, Nguyen Chanh, Nha Trang, Khanh Hoa (Viet Nam); Nan, Wen-Zhe [Department of Physics, Chungbuk National University, Cheongju 361-763 (Korea, Republic of); Yu, YiKyung [Department of Mechanical and Aerospace Engineering, University of California, San Diego, CA 92093-0411 (United States); Tartakovsky, Daniel M., E-mail: dmt@ucsd.edu [Department of Mechanical and Aerospace Engineering, University of California, San Diego, CA 92093-0411 (United States); Yu, S.C., E-mail: scyu@cbnu.ac.kr [Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Hanoi (Viet Nam)

    2015-11-15

    In this work, we prepared nanocrystalline Fe{sub 2}Mn{sub 1−x}Cu{sub x}Al (x=0.0, 0.1 and 0.3) powders by the high energy ball milling technique, and then studied their critical properties. Our analysis reveals that the increase of Cu-doping concentration (up to x=0.3) in these powders leads to a gradual increase of the ferromagnetic–paramagnetic transition temperature from 406 to 452 K. The Banerjee criterion suggests that all the samples considered undergo a second-order phase transition. A modified Arrott plot and scaling analysis indicate that the critical exponents (β=0.419 and 0.442, γ=1.082 and 1.116 for x=0.0 and 0.1, respectively) are located in between those expected for the 3D-Heisenberg and the mean-field models; the values of β=0.495 and γ=1.046 for x=0.3 sample are very close to those of the mean-field model. These features reveal the coexistence of the short- and long-range ferromagnetic order in the nanocrystalline Fe{sub 2}Mn{sub 1−x}Cu{sub x}Al powders. Particularly, as the concentration of Cu increases, values of the critical exponent shift towards those of the mean-field model. Such results prove the Cu doping favors establishing a long-range ferromagnetic order. - Highlights: • Fe{sub 2}Mn{sub 1−x}Cu{sub x}Al nanocrystals were prepared by a high energy ball milling method. • A coexistence of the short- and long-range FM order in the nanocrystals. • Cu doping favors establishing a long-range FM order in the nanocrystals. • All the ΔS{sub m}(T, H) data are followed a universal master curve.

  13. Uranium Mill Tailings Remedial Action Project Vicinity Property Program

    International Nuclear Information System (INIS)

    Little, L.E.; Potter, R.F.; Arpke, P.W.

    1988-01-01

    The Department of Energy Uranium Mill Tailings Remedial Action (UMTRA) Grand Junction Project Vicinity Property Program is a $165 million program for the removal and disposal of uranium mill tailings that were used in the construction of approximately 4,000 residences, commercial buildings, and institutional facilities in the City of Grand Junction and surrounding Mesa County, Colorado. This paper discusses the UMTRA Vicinity Property Program and the economic benefits of this program for the City of Grand Junction and Mesa County, Colorado. The Bureau of Reclamation Economic Assessment Model (BREAM) was used to estimate the increases in employment and increases in personal income in Mesa County that result from the Vicinity Property Program. The effects of program-related changes in income and taxable expenditures on local and state tax revenue are also presented

  14. Magnetic degradation of thin film multilayers during ion milling

    Directory of Open Access Journals (Sweden)

    J. C. Read

    2014-04-01

    Full Text Available We present a study of Ar ion milling-induced damage in exchange biased IrMn/CoFe/Ag-based magnetic multilayer thin films. While process variations determine the change in CoFe magnetic properties, the distance from the ion milling front to the IrMn/CoFe interface dominates the extent of exchange bias damage. Remarkably, the interfacial coupling energy Jk can be reduced by 50% before any removal of the CoFe pinned layer. We attribute the losses to microstructural changes and damage effects where cap material is driven into the CoFe layer below. Disturbance depth estimates from ion impact simulations agree reasonably with the observed length scales of damage.

  15. Cutting force simulation in milling with multi-edges cutter

    Science.gov (United States)

    Tamura, Shoichi; Matsumura, Takashi

    2017-10-01

    In the aircraft parts, the portion of titanium alloy, one of the light-weight and high mechanical strength materials, has been increased in terms of the fuel efficiency. Therefore, the effective technologies in cutting of titanium alloy should be established to promote the material removal rate with high production quality. Multi-edges milling cutters, on which many inserts are helically aligned, have been commercially available for millings of deep sinking in large axial depth of cuts. The paper presents an analytical prediction model to control the cutting force with alignment and geometry of the insert. In the model, three dimensional chip flow on each insert is interpreted as a piling up of the orthogonal cuttings in the planes containing the cutting velocities and the chip flow velocities, where the chip flow direction is determined to minimize the cutting energy. Then, the cutting force is predicted in the determined chip flow model. The cutting tests were conducted to validate the force model.

  16. Synthesis of Randomly Substituted Anionic Cyclodextrins in Ball Milling.

    Science.gov (United States)

    Jicsinszky, László; Caporaso, Marina; Calcio Gaudino, Emanuela; Giovannoli, Cristina; Cravotto, Giancarlo

    2017-03-19

    A number of influencing factors mean that the random substitution of cyclodextrins (CD) in solution is difficult to reproduce. Reaction assembly in mechanochemistry reduces the number of these factors. However, lack of water can improve the reaction outcomes by minimizing the reagent's hydrolysis. High-energy ball milling is an efficient, green and simple method for one-step reactions and usually reduces degradation and byproduct formation. Anionic CD derivatives have successfully been synthesized in the solid state, using a planetary ball mill. Comparison with solution reactions, the solvent-free conditions strongly reduced the reagent hydrolysis and resulted in products of higher degree of substitution (DS) with more homogeneous DS distribution. The synthesis of anionic CD derivatives can be effectively performed under mechanochemical activation without significant changes to the substitution pattern but the DS distributions were considerably different from the products of solution syntheses.

  17. Synthesis of Randomly Substituted Anionic Cyclodextrins in Ball Milling

    Directory of Open Access Journals (Sweden)

    László Jicsinszky

    2017-03-01

    Full Text Available A number of influencing factors mean that the random substitution of cyclodextrins (CD in solution is difficult to reproduce. Reaction assembly in mechanochemistry reduces the number of these factors. However, lack of water can improve the reaction outcomes by minimizing the reagent’s hydrolysis. High-energy ball milling is an efficient, green and simple method for one-step reactions and usually reduces degradation and byproduct formation. Anionic CD derivatives have successfully been synthesized in the solid state, using a planetary ball mill. Comparison with solution reactions, the solvent-free conditions strongly reduced the reagent hydrolysis and resulted in products of higher degree of substitution (DS with more homogeneous DS distribution. The synthesis of anionic CD derivatives can be effectively performed under mechanochemical activation without significant changes to the substitution pattern but the DS distributions were considerably different from the products of solution syntheses.

  18. N=1 supersymmetric Yang-Mills theory on the lattice

    Energy Technology Data Exchange (ETDEWEB)

    Piemonte, Stefano

    2015-04-08

    Supersymmetry (SUSY) relates two classes of particles of our universe, bosons and fermions. SUSY is considered nowadays a fundamental development to explain many open questions about high energy physics. The N=1 super Yang-Mills (SYM) theory is a SUSY model that describes the interaction between gluons and their fermion superpartners called ''gluinos''. Monte Carlo simulations on the lattice are a powerful tool to explore the non-perturbative dynamics of this theory and to understand how supersymmetry emerges at low energy. This thesis presents new results and new simulations about the properties of N=1 SYM, in particular about the phase diagram at finite temperature.

  19. Compactification of space-time in SU(∞) Yang-Mills theory

    International Nuclear Information System (INIS)

    Shiraishi, Kiyoshi.

    1989-02-01

    The compactification on torus in SU(∞) Yang-Mills (YM) theory is considered. A special form of configuration of gauge field on torus is examined. The vacuum energy and free energy in the presence of fermions coupled with this background in the theory are derived and possible symmetry breaking is investigated. (author)

  20. The enthalpy of the heat-carrying fluids and the energy of eruption of velican geyser, Kamchatka, U.S.S.R.

    Science.gov (United States)

    Steinberg, G. S.

    1980-10-01

    The enthalphy of the heat carrying fluids liquid water or mixture of water plus steam) which feeds the biggest Kamchatka geyser, Velican is obtained from the critical quantity of heat Q critical, which is the net heat lost during the previous eruption and must be resupplied (stored) to trigger the next eruption. There are two unknowns in the heat balance equation for the geyser that cannot be determined from observations on the geyser in its natural state: critical and the enthalpy of the heat-carrying fluids Io. In order to obtain a system of two equations for unambiguous determination of these parameters, we made temporary physical changes that affected the natural interval between geyser eruptions and constructed the heat balance equations for the different regimes (i.e., natural and induced intervals). The changes in interval of Velican geyser were achieved by changing the area of its surface pool, using dams. For geysers with large surface pool areas, the heat loss from the surface (mainly through evaporation) is of the same order and sometimes larger than the losses from discharge of hot water. The change of surface pool area for Velican geyser from 12 m 2 (in natural state) to 4.5 and 36.7 m 2 in experiments leads to changes of its interval from an average of 5 hours and 35 minutes in natural state to 4 hours and 59 minutes and 8 hours and 8 minutes, respectively. From the three independent equations of heat balance we obtained three sets cf values for the enthalpy, Io and the critical energy, Q critical, which differ from each other by less than 1%: Io= 176 kcal/kg ∗, Q critical = 3.78 × 10 6 kcal. The interval between eruptions of Velican geyser tends to change linearly with vent area (within our experimental range). The range or interval values (the difference between maximal and minimal periods) also depends linearly on vent area. These two systematics are due to the facts that the increase of vent surface area causes increased heat loss by