Improving mine-mill water network design by reducing water and energy requirements

Energy Technology Data Exchange (ETDEWEB)

Gunson, A.J.; Klein, B.; Veiga, M. [British Columbia Univ., Vancouver, BC (Canada). Norman B. Keevil Inst. of Mining Engineering

2010-07-01

Mining is an energy-intensive industry, and most processing mills use wet processes to separate minerals from ore. This paper discussed water reduction, reuse and recycling options for a mining and mill operation network. A mine water network design was then proposed in order to identify and reduce water and system energy requirements. This included (1) a description of site water balance, (2) a description of potential water sources, (3) a description of water consumers, (4) the construction of energy requirement matrices, and (5) the use of linear programming to reduce energy requirements. The design was used to determine a site water balance as well as to specify major water consumers during mining and mill processes. Potential water supply combinations, water metering technologies, and recycling options were evaluated in order to identify the most efficient energy and water use combinations. The method was used to highlight potential energy savings from the integration of heating and cooling systems with plant water systems. 43 refs., 4 tabs., 3 figs.

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)

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.

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

International Nuclear Information System (INIS)

Rojas-Chavez, H.; Reyes-Carmona, F.; Jaramillo-Vigueras, D.

2011-01-01

Highlights: → PbSe synthesized from PbO instead of Pb powder do not require an inert atmosphere. → During high-energy milling oxygen has to be chemically reduced from the lead oxide. → 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.

Quantum Yang–Mills Dark Energy

Directory of Open Access Journals (Sweden)

Roman Pasechnik

2016-02-01

Full Text Available In this short review, I discuss basic qualitative characteristics of quantum non-Abelian gauge dynamics in the non-stationary background of the expanding Universe in the framework of the standard Einstein–Yang–Mills formulation. A brief outlook of existing studies of cosmological Yang–Mills fields and their properties will be given. Quantum effects have a profound impact on the gauge field-driven cosmological evolution. In particular, a dynamical formation of the spatially-homogeneous and isotropic gauge field condensate may be responsible for both early and late-time acceleration, as well as for dynamical compensation of non-perturbative quantum vacua contributions to the ground state of the Universe. The main properties of such a condensate in the effective QCD theory at the flat Friedmann–Lemaítre–Robertson–Walker (FLRW background will be discussed within and beyond perturbation theory. Finally, a phenomenologically consistent dark energy can be induced dynamically as a remnant of the QCD vacua compensation arising from leading-order graviton-mediated corrections to the QCD ground state.

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.

Minimization of energy and surface roughness of the products machined by milling

Science.gov (United States)

Belloufi, A.; Abdelkrim, M.; Bouakba, M.; Rezgui, I.

2017-08-01

Metal cutting represents a large portion in the manufacturing industries, which makes this process the largest consumer of energy. Energy consumption is an indirect source of carbon footprint, we know that CO2 emissions come from the production of energy. Therefore high energy consumption requires a large production, which leads to high cost and a large amount of CO2 emissions. At this day, a lot of researches done on the Metal cutting, but the environmental problems of the processes are rarely discussed. The right selection of cutting parameters is an effective method to reduce energy consumption because of the direct relationship between energy consumption and cutting parameters in machining processes. Therefore, one of the objectives of this research is to propose an optimization strategy suitable for machining processes (milling) to achieve the optimum cutting conditions based on the criterion of the energy consumed during the milling. In this paper the problem of energy consumed in milling is solved by an optimization method chosen. The optimization is done according to the different requirements in the process of roughing and finishing under various technological constraints.

Direct measures of mechanical energy for knife mill size reduction of switchgrass, wheat straw, and corn stover.

Science.gov (United States)

Bitra, Venkata S P; Womac, Alvin R; Igathinathane, C; Miu, Petre I; Yang, Yuechuan T; Smith, David R; Chevanan, Nehru; Sokhansanj, Shahab

2009-12-01

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

New approach to recycling and waste-to-energy in paper production, Urban Mill

Energy Technology Data Exchange (ETDEWEB)

Ristola, P. [Metso Corporation (Finland)

2002-10-01

Greenfield paper mills are commonly perceived as massive investments with a high level of associated impact on the local environment. Parallel to this, increasingly strict targets are being set by modem legislation for reducing waste disposal at landfills. One long-term solution to this dilemma lies in extended materials recycling, combined with effective utilisation of waste as energy. Metso Paper's Urban Mill is a unique pilot concept that promises to become an important part of such a solution. The novelty of Metso Paper's new eco-efficient Urban Mill concept lies in its combination of a small paper mill with using solid waste to generate energy. The roots of the concept go back to the early 1990s, when several mini-mills were built to produce raw materials for corrugated containers in North America. The competitiveness of mini-mills like this is based on several benefits: lowcost, high-quality waste paper raw material, utilisation of adjacent facilities for utilities, and modern machines with lean manning and low inbound and outbound logistics costs.

Effect of the milling energy on the production and thermal stability of amorphous Mg50Ni50

International Nuclear Information System (INIS)

Guzman, D.; Ordonez, S.; Serafini, D.; Rojas, P.; Bustos, O.

2009-01-01

The effect of milling energy on the amorphisation process and subsequent thermal crystallization of Mg 50 Ni 50 was investigated. The amorphous Mg 50 Ni 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 50 Ni 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 2 Ni, which is subsequently destabilized into amorphous Mg 50 Ni 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 possible to conclude, that under the

Fabrication of Al-20 wt%Si powder using scrap Si by ultra high-energy milling process

Energy Technology Data Exchange (ETDEWEB)

Kang, Won-Kyung [Division of Advanced Materials Engineering and Institute for Rare Metals, Kongju National University, 275, Budae-dong, Cheonan, Chungnam 330-717 (Korea, Republic of); Y Latin-Small-Letter-Dotless-I lmaz, Fikret [Department of Physics, Faculty of Art and Science, Gaziosmanpasa University, Tasliciftlik Campus, 60240 Tokat (Turkey); Kim, Hyo-Seob; Koo, Jar-Myung [Division of Advanced Materials Engineering and Institute for Rare Metals, Kongju National University, 275, Budae-dong, Cheonan, Chungnam 330-717 (Korea, Republic of); Hong, Soon-Jik, E-mail: hongsj@kongju.ac.kr [Division of Advanced Materials Engineering and Institute for Rare Metals, Kongju National University, 275, Budae-dong, Cheonan, Chungnam 330-717 (Korea, Republic of)

2012-09-25

Highlights: Black-Right-Pointing-Pointer High energy ball milling process has been successfully employed to produce Al-20Si alloy using scrap Si powders. Black-Right-Pointing-Pointer Fully finer and homogenous structure could be achieved after 60 min of milling time. Black-Right-Pointing-Pointer Si particles were not dissolved but uniformly dispersed in the Al matrix in a milled state. Black-Right-Pointing-Pointer The hardness of as-milled Al-20Si powder increased steadily with the increase of milling time. Black-Right-Pointing-Pointer Grain size and dispersion strengthening are two mechanisms being responsible for hardness increment. - Abstract: In this study, microstructural evolution and mechanical properties of Al-20 wt%Si and pure Al powders fabricated by ultra high-energy ball milling technique were investigated as a function of milling time. The microstructure and mechanical properties of the as-milled powders were examined by scanning electron microscope (SEM), energy dispersive spectrometry (EDS), X-ray diffractometer (XRD) and Vickers hardness tester. SEM observation showed that the particle size increased at an early stage of milling, and then decreased drastically with further milling. XRD and cross-sectional EDS-mapping analyses revealed that Si particles were not dissolved but uniformly dispersed in the Al matrix in a milled state. Vickers hardness of both pure Al and Al-Si powder increases with milling time, which attributes to the grain size strengthening and dispersion strengthening.

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.

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)

A Scandinavian chemical wood pulp mill. Part 1. Energy audit aiming at efficiency measures

Energy Technology Data Exchange (ETDEWEB)

Klugman, Sofia [Department of Technology and Building Environment, Gaevle University, SE-801 76 Gaevle (Sweden); Karlsson, Magnus; Moshfegh, Bahram [Department of Mechanical Engineering, Division of Energy Systems, Linkoeping University, SE-581 83 Linkoeping (Sweden)

2007-03-15

A Swedish wood-pulp mill is surveyed in terms of energy supply and use in order to determine the energy-saving potential. Conservation measures are of increasing interest to Swedish industry, as energy prices have continued to rise in recent years. The electricity price particularly increased after the deregulation of the Scandinavian electricity market in 1996. The deregulation expanded to all of the EU in July 2004, which may increase the Swedish electricity price further until it reaches the generally higher European price level. Furthermore, oil prices have increased and the emissions trading scheme for CO{sub 2} adds to the incentive to reduce oil consumption. The energy system at the surveyed pulp mill is described in terms of electricity and process heat production and use. The total energy-saving potential is estimated and some saving points are identified. The heat that today is wasted at the mill has been surveyed in order to find potential for heat integration or heat export. The result shows that the mill probably could become self-sufficient in electricity. Particularly important in that endeavour is updating old pumps. (author)

Characterization of prealloyed copper powders treated in high energy ball mill

International Nuclear Information System (INIS)

Rajkovic, Viseslava; Bozic, Dusan; Jovanovic, Milan T.

2006-01-01

The inert gas atomised prealloyed copper powders containing 3.5 wt.% Al were milled up to 20 h in the planetary ball mill in order to oxidize aluminium in situ with oxygen from the air. In the next procedure compacts from milled powder were synthesized by hot-pressing in argon atmosphere. Compacts from as-received Cu-3.5 wt.% Al powder and electrolytic copper powder were also prepared under the same conditions. Microstructural and morphological changes of high energy milled powder as well as changes of thermal stability and electrical conductivity of compacts were studied as a function of milling time and high temperature exposure at 800 deg. C. Optical, scanning electron microscopy (SEM) and X-ray diffraction analysis were performed for microstructural characterization, whereas thermal stability and electrical conductivity were evaluated by microhardness measurements and conductometer Sigmatest, respectively. The prealloyed 5 h-milled and compacted powder showed a significant increase in microhardness reaching the value of 2600 MPa, about 4 times greater than that of compacts synthesized from as-received electrolytic copper powder (670 MPa). The electrical conductivity of compacts from 5 h-milled powder was 52% IACS. The results were discussed in terms of the effect of small grain size and finely distributed alumina dispersoids on hardening and thermal stability of compacts

Production of nanocrystalline cermet thermal spray powders for wear resistant coatings by high-energy milling

International Nuclear Information System (INIS)

Eigen, N.; Klassen, T.; Aust, E.; Bormann, R.; Gaertner, F.

2003-01-01

TiC-Ni based nanocrystalline cermet powders for thermal spraying were produced by high-energy milling. Milling experiments were performed in an attrition mill and a vibration mill in kilogram scale, and powder morphologies and microstructures were characterized using scanning electron microscopy, X-ray diffraction, and laser scattering for particle size analysis. Milling time and powder input were optimized with respect to the desired microstructure and particle sizes, and the results using both types of mill were compared. Powders with homogeneously dispersed hard phase particles below 300 nm could be produced in both mills. Additional processes for the refinement of powder morphology and particle size distribution are discussed

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.

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...

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.

Fabrication of lanthanum-doped thorium dioxide by high-energy ball milling and spark plasma sintering

Energy Technology Data Exchange (ETDEWEB)

Scott, Spencer M.; Yao, Tiankai [Department of Mechanical, Aerospace, and Nuclear Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY 12180 (United States); Lu, Fengyuan [Department of Mechanical & Industrial Engineering, Louisiana State University, Baton Rouge, LA 70803 (United States); Xin, Guoqing; Zhu, Weiguang [Department of Mechanical, Aerospace, and Nuclear Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY 12180 (United States); Lian, Jie, E-mail: lianj@rpi.edu [Department of Mechanical, Aerospace, and Nuclear Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY 12180 (United States)

2017-03-15

Abstract: High-energy ball milling was used to synthesize Th{sub 1-x}La{sub x}O{sub 2-0.5x} (x = 0.09, 0.23) solid solutions, as well as improve the sinterability of ThO{sub 2} powders. Dense La-doped ThO{sub 2} pellets with theoretical density above 94% were consolidated by spark plasma sintering at temperatures above 1400 °C for 20 min, and the densification behavior and the non-equilibrium effects on phase and structure were investigated. A lattice contraction of the SPS-densified pellets occurred with increasing ball milling duration, and a secondary phase with increased La-content was observed in La-doped pellets. A dependence on the La-content and sintering duration for the onset of localized phase segregation has been proposed. The effects of high-energy ball milling, La-content, and phase formation on the thermal diffusivity were also studied for La-doped ThO{sub 2} pellets by laser flash measurement. Increasing La-content and high energy ball milling time decreases thermal diffusivity; while the sintering peak temperature and holding time beyond 1600 °C dramatically altered the temperature dependence of the thermal diffusivity beyond 600 °C. - Highlights: • Lanthanum incorporation into ThO{sub 2} by high energy ball milling and rapid consolidation by spark plasma sintering. • Elucidation of phase behavior of the La-doped ThO{sub 2} and the contributions of La incorporation and SPS sintering conditions. • Investigation of the effects of La incorporation and high energy ball milling on the thermal behavior of La-doped ThO{sub 2}.

Simulation of solid-liquid flows in a stirred bead mill based on computational fluid dynamics (CFD)

Science.gov (United States)

Winardi, S.; Widiyastuti, W.; Septiani, E. L.; Nurtono, T.

2018-05-01

The selection of simulation model is an important step in computational fluid dynamics (CFD) to obtain an agreement with experimental work. In addition, computational time and processor speed also influence the performance of the simulation results. Here, we report the simulation of solid-liquid flow in a bead mill using Eulerian model. Multiple Reference Frame (MRF) was also used to model the interaction between moving (shaft and disk) and stationary (chamber exclude shaft and disk) zones. Bead mill dimension was based on the experimental work of Yamada and Sakai (2013). The effect of shaft rotation speed of 1200 and 1800 rpm on the particle distribution and the flow field was discussed. For rotation speed of 1200 rpm, the particles spread evenly throughout the bead mill chamber. On the other hand, for the rotation speed of 1800 rpm, the particles tend to be thrown to the near wall region resulting in the dead zone and found no particle in the center region. The selected model agreed well to the experimental data with average discrepancies less than 10%. Furthermore, the simulation was run without excessive computational cost.

Characterization of tin selenides synthesized by high-energy milling

Directory of Open Access Journals (Sweden)

Marcela Achimovičová

2011-12-01

Full Text Available Tin selenides SnSeX (x=1,2 were synthesized from tin and selenium powder precursors by high-energy milling in the planetary ballmill Pulverisette 6 (Fritsch, Germany. The orthorhombic tin selenide SnSe and the hexagonal tin diselenide SnSe2 phases were formed after4 min and 5 min of milling, respectively. Specific surface area of both selenides increased with increasing time of mechanochemicalsynthesis. The particle size distribution analysis demonstrated that the synthesized products contain agglomerated selenide particlesconsisting of numerous idiomorphic tin selenide crystals, measuring from 2 to more than 100 nm in diameter, which were also documentedby TEM. UV-Vis spectrophotometry confirmed that tin selenide particles do not behave as quantum dots.

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...

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 preparation of nanocrystalline troilite by high-energy milling of FeS2 sulphide with elemental Fe acting as reducing element is reported. X-ray difractometry was used in order to determine the presence of different phases in investigated samples. This technique allowed us to identify the form......-->troilite transformation is almost finished already after 25 minutes of high-energy milling.......The preparation of nanocrystalline troilite by high-energy milling of FeS2 sulphide with elemental Fe acting as reducing element is reported. X-ray difractometry was used in order to determine the presence of different phases in investigated samples. This technique allowed us to identify...

Simulation of ball motion and energy transfer in a planetary ball mill

International Nuclear Information System (INIS)

Lu Sheng-Yong; Mao Qiong-Jing; Li Xiao-Dong; Yan Jian-Hua; Peng Zheng

2012-01-01

A kinetic model is proposed for simulating the trajectory of a single milling ball in a planetary ball mill, and a model is also proposed for simulating the local energy transfer during the ball milling process under no-slip conditions. Based on the kinematics of ball motion, the collision frequency and power are described, and the normal impact forces and effective power are derived from analyses of collision geometry. The Hertzian impact theory is applied to formulate these models after having established some relationships among the geometric, dynamic, and thermophysical parameters. Simulation is carried out based on two models, and the effects of the rotation velocity of the planetary disk Ω and the vial-to-disk speed ratio ω/Ω on other kinetic parameters is investigated. As a result, the optimal ratio ω/Ω to obtain high impact energy in the standard operating condition at Ω = 800 rpm is estimated, and is equal to 1.15. (interdisciplinary physics and related areas of science and technology)

Research kinetic of motion of milling bodies in ball mill, outfit heat-exchange unit and calculation of its energy performance

Science.gov (United States)

Romanovich, A. A.; Romanovich, M. A.; Apukhtina, I. V.

2018-03-01

The article considers topical issues of energy saving in cement production with the use of a technological grinding complex, which includes a press roller grinder and a ball mill. Rational conditions of grinding are proposed for pre-shredded material through the installation of blade energy exchange devices (BEED) in the mill drum. The loading level in the first chamber varies periodically depending on the drum rotation angle, equipped with BEED. In the zone of BEED’s active action, there is a “scooping” of a part of grinding bodies together with crushed material, raising them to a height and giving them a longitudinally transverse movement, which is different from movement created in the mill without BEED. At the same time, additional work that consumes engine power is being done. A technique is proposed for calculating the additional engine power consumption of a mill, equipped with a BEED. This power is spent on creating a longitudinal-transverse motion of grinding bodies and its first and second chambers in areas of active influence of the BEED. Comparative analysis of results obtained experimentally and calculations of proposed equations show a high convergence of results. These analytical dependencies may be interest to Russian and foreign organizations that carry out their activities in the field of design and manufacture of cement equipment, as well as to cement producers.

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

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.

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...

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

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

The potential for energy savings when reducing the water consumption in a kraft pulp mill

Energy Technology Data Exchange (ETDEWEB)

Wising, Ulrika; Berntsson, Thore [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Chemical Engineering and Environmental Science; Stuart, Paul [Ecole Polytechnique, Montreal (Canada). Dept. of Chemical Engineering

2004-05-01

In this paper an existing pulp and paper mill has been studied in a systematic way regarding the reduction of water consumption, and the resulting increased potential for energy integration. It has been found that when the mill's hot water consumption is decreased, the live steam demand for the mill also decreases. Also when decreasing the hot water consumption, the quantity and temperature of available excess heat increases. This excess heat can be used for evaporation, thereby reducing the live steam demand further by up to 1.5 GJ/t. A pinch analysis was performed at an existing mill and it was found that if pinch violations are removed, the hot water consumption is not an important factor any more. Removing all the pinch violations and using the remaining excess heat for evaporation yields a significantly larger energy savings for the mill (4.0 GJ/t). From an economic optimum perspective it is probably most profitable to do a combination of reducing water consumption, removing pinch violations, and use the remaining excess heat for evaporation.

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)

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.

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)

Comparison of various milling modes combined to the enzymatic hydrolysis of lignocellulosic biomass for bioenergy production: Glucose yield and energy efficiency

International Nuclear Information System (INIS)

Licari, A.; Monlau, F.; Solhy, A.; Buche, P.; Barakat, A.

2016-01-01

Bagasse is an abundant by-product from sugarcane production that can be used for conversion into biofuels. Nonetheless, the recalcitrant structures of lignocellulosic fibers required a pretreatment prior conversion into biofuels. In this study, four mechanical deconstruction methods were compared in terms of energy demand and energy efficiency at lab scale: BM (ball mill), VBM (vibratory ball mill), CM (centrifugal mill) and JM (jet mill). Results indicate that VBM was more effective compared to BM, JM and CM in enzymatic accessibility and sugars solubilization: VBM-3h > BM-72 h > JM-5000 rpm > CM-0.12 mm. However, preliminary energetic assessment showed that at lab scale, the CM (centrifugal mill) as mechanical fractionation process appears to be the most efficient in terms of energy-efficiency (kg glucose/kWh) compared to BM, VBM and JM. A comparison with literature pretreatments data highlighted that fine and/or ultrafine milling process (BM, VBM, CM) are simpler saccharification technologies, which not required any chemical or water inputs, thus minimizing waste generation and treatment. - Highlights: • VBM (vibro ball milling) was the most effective in decreasing of cellulose crystallinity. • BM (ball milling) was the most effective in increasing surface area. • The highest energy efficiency was obtained with CM (centrifugal milling).

Chatter detection in milling process based on VMD and energy entropy

Science.gov (United States)

Liu, Changfu; Zhu, Lida; Ni, Chenbing

2018-05-01

This paper presents a novel approach to detect the milling chatter based on Variational Mode Decomposition (VMD) and energy entropy. VMD has already been employed in feature extraction from non-stationary signals. The parameters like number of modes (K) and the quadratic penalty (α) need to be selected empirically when raw signal is decomposed by VMD. Aimed at solving the problem how to select K and α, the automatic selection method of VMD's based on kurtosis is proposed in this paper. When chatter occurs in the milling process, energy will be absorbed to chatter frequency bands. To detect the chatter frequency bands automatically, the chatter detection method based on energy entropy is presented. The vibration signal containing chatter frequency is simulated and three groups of experiments which represent three cutting conditions are conducted. To verify the effectiveness of method presented by this paper, chatter feather extraction has been successfully employed on simulation signals and experimental signals. The simulation and experimental results show that the proposed method can effectively detect the chatter.

Nitrogen-doped graphene by ball-milling graphite with melamine for energy conversion and storage

International Nuclear Information System (INIS)

Xue, Yuhua; Chen, Hao; Qu, Jia; Dai, Liming

2015-01-01

N-doped graphene was prepared by ball milling of graphite with melamine. It was found that ball-milling reduced the size of graphite particles from 30 to 1 μm and facilitated the exfoliation of the resultant small particles into few-layer N-doped graphene nanosheets under ultrasonication. The as-prepared N-doped graphene nanoplatelets (NGnPs) exhibited a nitrogen content as high as 11.4 at.%, making them attractive as efficient electrode materials in supercapacitors for energy storage and as highly-active metal-free catalysts for oxygen reduction in fuel cells for energy conversion. (paper)

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.

Preparation of 50Ni-45Ti-5Zr powders by high-energy ball milling and hot pressing

Energy Technology Data Exchange (ETDEWEB)

Marinzeck de Alcantara Abdala, Julia, E-mail: juabdala@yahoo.com.b [Instituto de Pesquisa e Desenvolvimento, Universidade do Vale do Paraiba, Av. Shishima Hifumi, 2911, 12244-000 Sao Jose dos Campos (Brazil); Bacci Fernandes, Bruno, E-mail: brunobacci@yahoo.com.b [Divisao de Engenharia Mecanica, Instituto Tecnologico de Aeronautica, Praca Marechal-do-Ar Eduardo Gomes, 50, 12228-904 Sao Jose dos Campos (Brazil); Santos, Dalcy Roberto dos, E-mail: dalcy@iae.cta.b [Instituto de Aeronautica e Espaco, Centro Tecnologico Aeroespacial, Praca Marechal-do-Ar Eduardo Gomes, 50, 12228-904 Sao Jose dos Campos (Brazil); Rodrigues Henriques, Vinicius Andre, E-mail: vinicius@iae.cta.b [Instituto de Aeronautica e Espaco, Centro Tecnologico Aeroespacial, Praca Marechal-do-Ar Eduardo Gomes, 50, 12228-904 Sao Jose dos Campos (Brazil); Moura Neto, Carlos de, E-mail: mneto@ita.b [Divisao de Engenharia Mecanica, Instituto Tecnologico de Aeronautica, Praca Marechal-do-Ar Eduardo Gomes, 50, 12228-904 Sao Jose dos Campos (Brazil); Saraiva Ramos, Alfeu, E-mail: alfeu@univap.b [Instituto de Pesquisa e Desenvolvimento, Universidade do Vale do Paraiba, Av. Shishima Hifumi, 2911, 12244-000 Sao Jose dos Campos (Brazil)

2010-04-16

This study reports on the preparation of the 50Ni-45Ti-5Zr (at.%) alloy by high-energy ball milling and hot pressing. The elemental powder mixture was processed in silicon nitride and hardened steel vials, and samples were collected after different milling times. To recover the previous powders in addition wet milling isopropyl alcohol (for 20 min) was adopted. The mechanically alloyed powders were hot-pressed under vacuum at 900 {sup o}C for 1 h using pressure levels close to 200 MPa. The milled powders were characterized by means of scanning electron microscopy, X-ray diffraction, and energy dispersive spectrometry techniques. It was noted that the ductile starting powders were continuously cold-welded during ball milling. This fact was more pronounced during the processing of 50Ni-45Ti-5Zr powders in hardened steel vial. After milling for 5 h, the results suggested that amorphous and nanocrystalline structures were achieved. The complete consolidation was found after hot pressing of mechanically alloyed 50Ni-45Ti-5Zr powders, and a large amount of the B2-NiTi phase was formed mainly after processing in stainless steel balls and vial.

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.

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.

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.

Structural evolution in nanocrystalline Cu obtained by high-energy mechanical milling: Phases formation of copper oxides

International Nuclear Information System (INIS)

Khitouni, Mohamed; Daly, Rakia; Mhadhbi, Mohsen; Kolsi, Abdelwaheb

2009-01-01

Nanocrystalline copper with mean crystallite size of 18 nm was synthesized by using high-energy mechanical milling. The structural and morphological changes during mechanical milling especially, the formation of CuO and Cu 2 O phases were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy in transmittance mode (FTIR). Mechanical milling of Cu results in a continuous decrease in the Cu means crystallite size and an increase in microstrain. Moreover, milling of Cu, in air synthetic, results in partial oxidation to Cu 2 O and CuO. Prolonged milling supports the formation of CuO oxide. SEM results show that flattened Cu flakes were laid and welded on each other and tend to form a matrix of randomly welded thin layers of highly deformed particles.

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

Processing of an AISI D2 tool steel by high-energy milling

International Nuclear Information System (INIS)

Spagnol, N.J.R.; Araujo, G.F.; Vurobi Junior, S.; Cintho, O.M.

2009-01-01

Full text: Chips of machining of AISI D2 steel were processed in Spex high-energy mill. The powder obtained was analyzed by x-ray diffraction, and then compressed in the form of discs of 8mm in diameter. The samples were treated at 1200 deg C for 1 hour under vacuum atmosphere for sintering. Then specimens were subjected to annealing, quenching and tempering at 400°C and 525 deg C. Along with each disc, a sample of as-received steel was subjected to the same heat treatment to evaluate the final microstructures. After metallographic preparation, samples were etched with Berah's reagent, characterized by optical microscopy, Vickers hardness, quantitative metallography and scanning electron microscopy with micro analysis and mapping by EDS. Specimens from high energy milling had reduction in prior austenitic grain size and more refined carbides and better distributed in the microstructure of steel. (author)

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.

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 The main focus of this work was to evaluate an opportunity for product quality and refining energy efficiency improvement through assessing the current mill practices in South African TMP mills. The fractionation trials were conducted at a CSIR...

Reverse martensitic transformation in alumina-15 vol% zirconia nanostructured powder synthesized by high energy ball milling

Energy Technology Data Exchange (ETDEWEB)

Maneshian, M.H. [Department of Materials Science and Engineering, Sharif University of Technology, Azadi Avenue, P.O. Box 11365-9466, Tehran (Iran, Islamic Republic of)], E-mail: mh_maneshian@yahoo.com; Banerjee, M.K. [National Institute of Foundry and Forge Technology, Hatia, Ranchi 834003 (India)

2008-07-14

In the present work, three alumina-15 vol% zirconia composites with Y{sub 2}O{sub 3}, MgO as dopants and without oxide as dopant have been investigated. High energy ball milling (HEBM) provides the positive thermodynamic driving force for monoclinic to tetragonal transformation and it reduces starting temperature for the reverse martensitic transformation, meanwhile mobility of zirconium cations and oxygen anions are enhanced in zirconia by HEBM. The general, albeit heuristic, reasoning is corroborated by nanocrystallity, particle size and also the retained monoclinic seem to play an important role. After 10 h HEBM, approximately 28% zirconia tetragonal phase is achieved. Non-stoichiometric tetragonal zirconia phase; Zr{sub 0.95}O{sub 2} is seen to have been achieved by high energy ball milling (HEBM). The structural and compositional evolutions during HEBM have been investigated using X-ray diffraction method (XRD) and scanning electron microscopy (SEM). High resolution transmission electron microscope (TEM) is also used for further understanding about the phenomenological changes taking place during high energy ball milling.

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.

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.

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

Multiple direct exchange in a Yang-Mills theory at high energy

International Nuclear Information System (INIS)

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

1976-01-01

For eighth and higher orders, we obtain the leading high-energy behavior of the sum of all one-layer Feynman diagrams in Yang-Mills theory. These are the contributions from Feynman diagrams where the two incident fast particles exchange directly Yang-Mills bosons that are much less energetic. The incident particles may be either bosons or fermions of arbitrary isospin, and the result is also generalized to include the case of the Higgs scalar. The scattering amplitudes in all these cases are closely related, and all behave as s ln/sub n/ -1 s in the 2n + 2 order. Furthermore, in this leading order for n > or = 2, the exchanged isospins are always 0 and 2, no matter how high the isospins of the incident particles are

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...

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.

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.)

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

Energy Technology Data Exchange (ETDEWEB)

Fathinia, Siavash [Department of Mining Engineering, Faculty of Engineering and Technology, Imam Khomeini International University, Qazvin (Iran, Islamic Republic of); Research Laboratory of Advanced Water and Wastewater Treatment Processes, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of); Fathinia, Mehrangiz [Research Laboratory of Advanced Water and Wastewater Treatment Processes, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of); Rahmani, Ali Akbar [Department of Mining Engineering, Faculty of Engineering and Technology, Imam Khomeini International University, Qazvin (Iran, Islamic Republic of); Khataee, Alireza, E-mail: a_khataee@tabrizu.ac.ir [Research Laboratory of Advanced Water and Wastewater Treatment Processes, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of)

2015-02-01

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{sub 2}O{sub 2} concentration of 5 mmol/L, catalyst amount of 0.5 g/L and reaction time of 25 min.

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.

CNTs/Al5083 Composites of High-performance Uniform and Dispersion Fabricated by High-energy Ball-milling

Directory of Open Access Journals (Sweden)

GUO Li

2017-11-01

Full Text Available Carbon nanotubes (CNTs, mass fraction of 0%-2% reinforced Al5083 composites were fabricated by horizontal high-energy ball milling. The effects of ball milling time and CNTs contents on the properties of composite materials were studied. The micro morphology of CNTs/Al5083 composites was characterized by scanning electron microscopy(SEM and transmission electron microscopy(TEM, the tensile strength and microhardness of the composites were tested. The results indicate that after high-energy ball milling for 1.5h, the carbon nanotubes are dispersed homogeneously in the Al5083 matrix, and good interfacial bonding strength between CNTs and Al5083 is obtained at the addition of 1.5%CNTs. Under these conditions, the tensile strength and microhardness of CNTs/Al5083 composites are 188.8MPa and 136HV, respectively. Compared to Al5083 matrix without CNTs reinforcement, tensile strength and microhardness of CNTs/Al5083 composites are increased by 32.2% and 36%, respectively.

Two-perfect fluid interpretation of an energy tensor

International Nuclear Information System (INIS)

Ferrando, J.J.; Morales, J.A.; Portilla, M.

1990-01-01

There are many topics in General Relativity where matter is represented by a mixture of two fluids. In fact, some astrophysical and cosmological situations need to be described by an energy tensor made up of the sum of two or more perfect fluids rather than that with only one. The paper contains the necessary and sufficient conditions for a given energy tensor to be interpreted as a sum of two perfect fluids. Given a tensor of this class, the decomposition in two perfect fluids (which is determined up to a couple of real functions) is obtained

Moessbauer analysis of high-energy mechanical-milled sand fraction of a magnetic soil developing on basalt

Energy Technology Data Exchange (ETDEWEB)

Borges, Jose Flavio Marcelino; Hneda, Marlon Luiz; Brinatti, Andre Mauricio [State University of Ponta Grossa, Department of Physics (Brazil); Cunha, Joao Batista Marimon da [Federal University of Rio Grande do Sul, Institute of Physics (Brazil); Rosa, Jadir Aparecido [Polo Regional de Ponta Grossa, Agronomy Institute of Parana (Brazil); Fabris, Jose Domingos, E-mail: jdfabris@ufmg.br [Federal University of Jequitinhonha and Mucuri Valleys (UFVJM) (Brazil)

2011-11-15

A sample of the coarse sand fraction from the soil material of the A-horizon (0-0.2 m from the soil surface) of a dusky red magnetic Oxisol was submitted to high-energy mechanical milling for different times. This assay aimed mainly at (a) monitoring the individualization of strongly aggregated mineral particles, and (b) measuring the effect of the milling pressure on the mineralogy changes of the material. These data are also intended to experimentally subside any physical model describing the mechanical behavior of the superficial soil layer that is subjected to intensive machine management, in agriculture fields. Powder X-ray data reveal that some mineralogical phases, notably gibbsite, disappear soon after the first few hours milling. The 298 K-transmission Moessbauer spectrum for the non-milled sand sample shows a qualitatively typical pattern for the sand fraction of basalt derived soils, with magnetically ordered sextets, assignable mainly to hematite and maghemite, and an intense central (super)paramagnetic Fe{sup 3 + } doublet. For the milled samples, spectra revealed progressive spectral reduction of the magnetic hyperfine structure, with concomitant increase of relative subspectral areas due to (super)paramagnetic phases, as the milling time increased. This result is consistent with the reduction of measured saturation magnetization, from 4.96(8) J T{sup - 1} kg{sup - 1}, for the non-milled sample, to 3.26(7) J T{sup - 1} kg{sup - 1}, for the sample milled for 8 hours.

Low-energy mechanically milled τ-phase MnAl alloys with high coercivity and magnetization

International Nuclear Information System (INIS)

Lu, Wei; Niu, Junchao; Wang, Taolei; Xia, Kada; Xiang, Zhen; Song, Yiming; Zhang, Hong; Yoshimura, Satoru; Saito, Hitoshi

2016-01-01

The high cost of rare earth elements makes the use of high-performance permanent magnets commercially very expensive. MnAl magnetic material is one of the most promising Rare-Earth-free permanent magnets due to its obvious characteristics. However, the coercivity of MnAl alloys produced by melt spinning followed by appropriate treatment is relatively low. In this investigation, a high coercivity up to 5.3 kOe and saturation magnetization of ∼62 emu/g (with an applied magnetic field of 19.5 kOe) were obtained in the mechanically milled τ-phase Mn_5_7Al_4_3 alloy. As milling time goes on, the coercivity firstly increases and then decreases, leading to the formation of knee-point coercivity, while the saturation magnetization decreases simultaneously. The structural imperfections such as disordering and defects play the most important role in the changes of magnetic properties of τ-phase MnAl alloys processed by low-energy mechanical milling. The present results will be helpful for the development of processing protocols for the optimization of τ-phase MnAl alloys as high performance Rare-Earth-free permanent magnets. - Highlights: • Successful fabrication of pure τ-phase Mn_5_7Al_4_3 alloy by melt spinning and low-energy ball milling processes. • High coercivity (~5.3 kOe) and magnetization (~62 emu/g) were obtained in τ-phase Mn_5_7Al_4_3 alloy. • Disordering and defects play the most important role in the changes of magnetic properties.

Low-energy mechanically milled τ-phase MnAl alloys with high coercivity and magnetization

Energy Technology Data Exchange (ETDEWEB)

Lu, Wei, E-mail: weilu@tongji.edu.cn [School of Materials Science and Engineering, Shanghai Key Lab. of D& A for Metal-Functional Materials, Tongji University, Shanghai 200092 (China); Research Center for Engineering Science, Akita University, Akita 010-8502 Japan (Japan); Niu, Junchao; Wang, Taolei; Xia, Kada; Xiang, Zhen; Song, Yiming [School of Materials Science and Engineering, Shanghai Key Lab. of D& A for Metal-Functional Materials, Tongji University, Shanghai 200092 (China); Zhang, Hong; Yoshimura, Satoru; Saito, Hitoshi [Research Center for Engineering Science, Akita University, Akita 010-8502 Japan (Japan)

2016-08-05

The high cost of rare earth elements makes the use of high-performance permanent magnets commercially very expensive. MnAl magnetic material is one of the most promising Rare-Earth-free permanent magnets due to its obvious characteristics. However, the coercivity of MnAl alloys produced by melt spinning followed by appropriate treatment is relatively low. In this investigation, a high coercivity up to 5.3 kOe and saturation magnetization of ∼62 emu/g (with an applied magnetic field of 19.5 kOe) were obtained in the mechanically milled τ-phase Mn{sub 57}Al{sub 43} alloy. As milling time goes on, the coercivity firstly increases and then decreases, leading to the formation of knee-point coercivity, while the saturation magnetization decreases simultaneously. The structural imperfections such as disordering and defects play the most important role in the changes of magnetic properties of τ-phase MnAl alloys processed by low-energy mechanical milling. The present results will be helpful for the development of processing protocols for the optimization of τ-phase MnAl alloys as high performance Rare-Earth-free permanent magnets. - Highlights: • Successful fabrication of pure τ-phase Mn{sub 57}Al{sub 43} alloy by melt spinning and low-energy ball milling processes. • High coercivity (~5.3 kOe) and magnetization (~62 emu/g) were obtained in τ-phase Mn{sub 57}Al{sub 43} alloy. • Disordering and defects play the most important role in the changes of magnetic properties.

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.

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

Effect of expansion temperature of expandable graphite on microstructure evolution of expanded graphite during high-energy ball-milling

International Nuclear Information System (INIS)

Yue Xueqing; Li Liang; Zhang Ruijun; Zhang Fucheng

2009-01-01

Two expanded graphites (EG), marked as EG-1 and EG-2, were prepared by rapid heating of expandable graphite to 600 and 1000 deg. C, respectively, and ball milled in a high-energy mill (planetary-type) under air atmosphere. The microstructure evolution of the ball-milled samples was characterized by X-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM). XRD analysis shows that the evolution degree of the average crystallite thickness along the c-axis (L c ) of EG-2 is lower than that of EG-1 during the milling process. From the HRTEM images of the samples after 100 h ball-milling, slightly curved graphene planes can be frequently observed both in the two EGs, however, EG-1 and EG-2 exhibit sharply curved graphene planes and smoothly curved graphene planes with high bending angles, respectively.

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)

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.

Whole tree chips for fuel and pulp can cut mill energy costs

Energy Technology Data Exchange (ETDEWEB)

Morey, J

1979-01-01

Wood that is decaying and going to waste amounts to over 5 billion tons, enough to replace the present oil consumption of the United States. Environmental thinning--removal of dead, dying, and less desirable trees--leaves room for other trees to grow. Environmental thinning should be acceptable to private landowners, making almost every stand of timber available for energy harvest. Environmental thinning uses a small feller buncher shear, a small to medium grapple skidder, and a whole tree chipper. Five or six men, two or three feller bunchers, two grapple skidders, and a whole tree chipper can produce 250 to 300 green tons of whole tree chips per day and deliver it to an energy plant for $10 to $12 per ton. Demand for wood for energy will raise pulpwood prices unless industry adopts whole tree utilization and environmental thinning. Wood energy provides a market for low grade wood. The whole tree chipper can separate stem chips for pulping and top chips, with bark and foliage, for energy uses. A dirt separator available on the Morbark total Chiparvestor helps remove sand, about 40% of the bark, and about 50% of twigs and foliage. Because the fiber has a value as energy, it will be economical to build better screening systems, providing cleaner pulp chips. After screening, bark will remain, but some mills are converting to 100% bark chips. A study indicates that converting from oil to wood and from roundwood to whole tree chips can result in a savings of $4 to $8 million per year for a 1,000 tpd pulp and paper mill.

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)

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...

Milling tool and method for removing a packer

International Nuclear Information System (INIS)

Davis, J.P.; Beeman, R.S.

1992-01-01

This patent describes a packer milling and retrieval tool including a mandrel having an upper milling portion with cutting blades for engaging the upper milling portion with cutting blades for engaging the upper end of a packer in cutting relation, and a lower retrieval portion for contacting the lower end of the packer for removal of the packer from the casing. It comprises an improved release means; a sleeve mounted on the mandrel; the sleeve when fingers are disengaged from the packer abutment and spaced downwardly therefrom being slidable upwardly on the mandrel from a differential fluid pressure exerted against opposite ends of the sleeve provided by pressurized drilling fluid discharged from the tool upon the upper end portion approaching the small diameter bore portion from lifting of the mandrel to position the fingers adjacent the reduced diameter portion for inward deflection of the fingers to permit the fingers to pass the packer bore upon upward lifting movement of the mandrel to release the tool from the packer

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)

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.

The state equation of Yang-Mills field dark energy models

International Nuclear Information System (INIS)

Zhao Wen; Zhang Yang

2006-01-01

In this paper, we study the possibility of building Yang-Mills (YM) field dark energy models with equation of state (EoS) crossing -1, and find that it cannot be realized by the single YM field models, no matter what kind of Lagrangian or initial condition. But the states of -1 -1 to <-1, and it will go to the critical state of ω = -1 with the expansion of the universe, which character is the same as the single YM field models, and the big rip is naturally avoided

Bioassay for uranium mill tailings

International Nuclear Information System (INIS)

Tschaeche, A.N.

1986-01-01

Uranium mill tailings are composed of fine sand that contains, among other things, some uranium (U/sup 238/ primarily), and all of the uranium daughters starting with /sup 230/Th that are left behind after the usable uranium is removed in the milling process. Millions of pounds of tailings are and continue to be generated at uranium mills around the United States. Discrete uranium mill tailings piles exist near the mills. In addition, the tailings materials were used in communities situated near mill sites for such purposes as building materials, foundations for buildings, pipe runs, sand boxes, gardens, etc. The Uranium Mill Tailings Remedial Action Project (UMTRAP) is a U.S. Department of Energy Program designed with the intention of removing or stabilizing the mill tailings piles and the tailings used to communities so that individuals are not exposed above the EPA limits established for such tailings materials. This paper discusses the bioassay programs that are established for workers who remove tailings from the communities in which they are placed

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.

The use of geochemical barriers for reducing contaminants emanating from uranium mill tailings

International Nuclear Information System (INIS)

Groffman, A.R.; Longmire, P.; Mukhopadhyay, B.; Downs, W.

1991-01-01

A problem facing the Department of Energy's Uranium Mill Tailings Remediation Action (UMTRA) Project is the contamination of local ground water by leachate emanating form the tailings piles. These fluids have a low pH and contain heavy metals and trace elements such as arsenic, molybdenum, nitrate, selenium, and uranium. In order to meet ground water standards low hydraulic conductivity covers are installed over the tailings embankment. in some cases it may be necessary to install a geochemical barrier down gradient from the tailings embankment in order to remove the hazardous constituents. By using geochemical barriers to reduce undesirable species form a contaminant plume, fluids emanating form beneath a repository can in effect be scrubbed before entering the water table. Materials containing adsorbing clays, iron oxyhydroxides and zeolites, and reducing materials such as coal and peat, are being used effectively to attenuate contaminants form uranium mill tailings. Experiments to directly determine attenuation capacities of selected buffer/adsorption materials were conducted in the laboratory. Batch leach tests were conducted in lieu of column tests when the hydraulic conductivity of materials was too low to use in columns and shales

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.

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.

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)

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

Science.gov (United States)

Postma, P R; Suarez-Garcia, E; Safi, C; 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 (0.3-1mm). Cell disintegration, proteins and carbohydrates released into the water phase followed a first order kinetics. The process is selective towards proteins over carbohydrates during early stages of milling. In general, smaller beads led to higher kinetic rates, with a minimum specific energy consumption of ⩽0.47kWhkg DW -1 for 0.3mm beads. After analysis of the stress parameters (stress number and stress intensity), it appears that optimal disintegration and energy usage for all strains occurs in the 0.3-0.4mm range. During the course of bead milling, the native structure of the marker protein Rubisco was retained, confirming the mildness of the disruption process. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

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.

Preparation of zinc ferrite nano powders by high energy wet-milling method and investigation of Crystallites size variation during this process

International Nuclear Information System (INIS)

Masoudi, H.; Aftabi, A.; Mozafari, M.; Amighian, J.

2007-01-01

In this research work ZnFe 2 O 4 nano powders were prepared by high-energy wet-milling process, using metallic Fe and Zn powders. The process was investigated by XRD technique. 10% of the zinc ferrite was formed after 10 h milling. The as-milled sample was annealed at 500, 550 and 600 d egree C . Ultimately a single sample was obtained at 600 d egree C . Using sherrer's formula, the mean crystallite size of the as-milled and annealed powders were calculated. These were in the range of 17.9 to 20.4 nm.

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.

Advanced power generation using biomass wastes from palm oil mills

International Nuclear Information System (INIS)

Aziz, Muhammad; Kurniawan, Tedi; Oda, Takuya; Kashiwagi, Takao

2017-01-01

This study focuses on the energy-efficient utilization of both solid and liquid wastes from palm oil mills, particularly their use for power generation. It includes the integration of a power generation system using empty fruit bunch (EFB) and palm oil mill effluent (POME). The proposed system mainly consists of three modules: EFB gasification, POME digestion, and additional organic Rankine cycle (ORC). EFBs are dried and converted into a syngas fuel with high calorific value through integrated drying and gasification processes. In addition, POME is converted into a biogas fuel for power generation. Biogas engine-based cogenerators are used for generating both electricity and heat. The remaining unused heat is recovered by ORC module to generate electricity. The influences of three EFB gasification temperatures (800, 900 and 1000 °C) in EFB gasification module; and working fluids and pressure in ORC module are evaluated. Higher EFB gasification leads to higher generated electricity and remaining heat for ORC module. Power generation efficiency increases from 11.2 to 24.6% in case of gasification temperature is increased from 800 to 1000 °C. In addition, cyclohexane shows highest energy efficiency compared to toluene and n-heptane in ORC module. Higher pressure in ORC module also leads to higher energy efficiency. Finally, the highest total generated power and power generation efficiency obtained by the system are 8.3 MW and 30.4%, respectively.

Synthesis of Ni3Ta, Ni2Ta and NiTa by high-energy ball milling and subsequent heat treatment

International Nuclear Information System (INIS)

Benites, H.S.N.; Silva, B.P da; Ramos, A.S.; Silva, A.A.A.P.; Coelho, G.C.; Lima, B.B. de

2014-01-01

The tantalum has relevance for the development of multicomponent Ni-based superalloys which are hardened by solid solution and precipitation mechanisms. Master alloys are normally used in the production step in order to produce refractory metals and alloys. The present work reports on the synthesis of Ni_3Ta, Ni_2Ta and NiTa by high-energy ball milling and subsequent heat treatment. The elemental Ni-25Ta, Ni-33Ta and Ni-50Ta (at.-%) powder mixtures were ball milled under Ar atmosphere using stainless steel balls and vials, 300 rpm and a ball-to-powder weight ratio of 10:1. Following, the as-milled samples were uniaxially compacted and heat-treated at 1100 deg C for 4h under Ar atmosphere. The characterization of as-milled and heat-treated samples was conducted by means of X-ray diffraction, scanning electron microscopy, and energy dispersive spectrometry. A large amount of Ni_3Ta, Ni_2Ta and NiTa was formed in the mechanically alloyed heat-treated Ni-25Ta, Ni-33Ta and Ni-50Ta alloys. (author)

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.

Ball-milling-induced crystallization and ball-milling effect on thermal crystallization kinetics in an amorphous FeMoSiB alloy

International Nuclear Information System (INIS)

Guo, F.Q.; Lu, K.

1997-01-01

Microstructure evolution in a melt-spun amorphous Fe 77.2 Mo 0.8 Si 9 B 13 alloy subjected to high-energy ball milling was investigated by means of X-ray diffraction (XRD), a transmission electron microscope (TEM), and a differential scanning calorimeter (DSC). It was found that during ball milling, crystallization occurs in the amorphous ribbon sample with precipitation of an α-Fe solid solution, and the amorphous sample crystallizes completely into a single α-Fe nanostructure (rather than α-Fe and borides as in the usual thermal crystallization products) when the milling time exceeds 135 hours. The volume fraction of material crystallized was found to be approximately proportional to the milling time. The fully crystallized sample with a single α-Fe nanophase exhibits an intrinsic thermal stability against phase separation upon annealing at high temperatures. The ball-milling effect on the subsequent thermal crystallization of the amorphous phase in an as-milled sample was studied by comparison of the crystallization products and kinetic parameters between the as-quenched amorphous sample and the as-milled sample was studied by comparison of the crystallization products and kinetic parameters between the as-quenched amorphous sample and the as-milled partially crystallized samples. The crystallization temperatures and activation energies for the crystallization processes of the residual amorphous phase were considerably decreased due to ball milling, indicating that ball milling has a significant effect on the depression of thermal stability of the residual amorphous phase

Obtaining beta phase in Ti through processing in high energy mill powders of Ti and Nb

International Nuclear Information System (INIS)

Milanez, Mateus; Ferretto, Aline; Rocha, Marcio Roberto da; Arnt, Angela Coelho; Milanez, Alexandre; Schaeffer, Lirio

2014-01-01

An orthopedic implant, ideal, must meet the requirements of biocompatibility, have good mechanical properties among others. Titanium and Niobium exhibit biocompatibility and the β-Ti phase relationships have the highest strength / weight among all titanium alloys, presenting lower values of elastic modulus. The alloy has mechanically produced specific microstructural characteristics and improved mechanical properties compared with conventional powder metallurgy. In this study, a titanium alloy with different additions of niobium was used. The metal powders were mixed via mechanical alloy in high energy mill (attritor). The powder samples were analyzed by X-ray diffraction (X-RD) and property held by adhesive wear testing with a Pin-on-Disk. The present study revealed that through the high-energy milling is possible the atomic interaction between Ti and Nb particles and the mechanical properties are affected by the concentration of Nb. (author)

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; Svensson, Inger-Lise; Berntsson, Thore; 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

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...

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.

Energy efficiency and policy in Swedish pulp and paper mills: A data envelopment analysis approach

International Nuclear Information System (INIS)

Blomberg, Jerry; Henriksson, Eva; Lundmark, Robert

2012-01-01

The paper provides an empirical assessment of the electricity efficiency improvement potential in the Swedish pulp and paper industry by employing data envelopment analysis (DEA) and mill-specific input and output data for the years 1995, 2000 and 2005. The empirical results are discussed in relation to the reported outcomes of the Swedish voluntary energy efficiency programme PFE. The estimated electricity efficiency gap is relatively stable over the time period; it equals roughly 1 TWh per year for the sample mills and this is three times higher than the corresponding self-reported electricity savings in PFE. This result is largely a reflection of the fact that in the pulp and paper industry electricity efficiency improvements are typically embodied in the diffusion of new capital equipment, and there is a risk that some of the reported measures in PFE simply constitute an inefficient speed-up of capital turnover. The above does not preclude, though, that many other measures in PFE may have addressed some relevant market failures and barriers in the energy efficiency market. Overall the analysis suggests that future energy efficiency programs could plausibly be better targeted at explicitly promoting technological progress as well as at addressing the most important information and behaviour-related failures. - Highlights: ► We provide an empirical assessment of the electricity efficiency improvement potential in the Swedish pulp and paper industry. ► The empirical results are discussed in relation to the reported outcomes of the Swedish voluntary energy efficiency programme PFE. ► The estimated electricity efficiency gap is relatively stable over the time period and equals roughly 1 TWh for the sample mills (three times higher than the corresponding self-reported electricity savings in PFE). ► The results suggest that future energy efficiency programs could be better targeted at explicitly promoting technological progress as well as at addressing the

Low energy dynamics of monopoles in supersymmetric Yang-Mills theories with hypermultiplets

International Nuclear Information System (INIS)

Kim, Chanju

2006-01-01

We derive the low energy dynamics of monopoles and dyons in N = 2 supersymmetric Yang-Mills theories with hypermultiplets in arbitrary representations by utilizing a collective coordinate expansion. We consider the most general case that Higgs fields both in the vector multiplet and in the hypermultiplets have nonzero vacuum expectation values. The resulting theory is a supersymmetric quantum mechanics which has been obtained by a nontrivial dimensional reduction of two-dimensional (4,0) supersymmetric sigma models with potentials

Yang-Mills theory in Coulomb gauge; Yang-Mills-theorie in Coulombeichung

Energy Technology Data Exchange (ETDEWEB)

Feuchter, C.

2006-07-01

In this thesis we study the Yang-Mills vacuum structure by using the functional Schroedinger picture in Coulomb gauge. In particular we discuss the scenario of colour confinement, which was originally formulated by Gribov. After a short introduction, we recall some basic aspects of Yang-Mills theories, its canonical quantization in the Weyl gauge and the functional Schroedinger picture. We then consider the minimal Coulomb gauge and the Gribov problem of the gauge theory. The gauge fixing of the Coulomb gauge is done by using the Faddeev-Popov method, which enables the resolution of the Gauss law - the constraint on physical states. In the third chapter, we variationally solve the stationary Yang-Mills Schroedinger equation in Coulomb gauge for the vacuum state. Therefor we use a vacuum wave functional, which is strongly peaked at the Gribov horizon. The vacuum energy functional is calculated and minimized resulting in a set of coupled Schwinger-Dyson equations for the gluon energy, the ghost and Coulomb form factors and the curvature in gauge orbit space. Using the angular approximation these integral equations have been solved analytically in both the infrared and the ultraviolet regime. The asymptotic analytic solutions in the infrared and ultraviolet regime are reasonably well reproduced by the full numerical solutions of the coupled Schwinger-Dyson equations. In the fourth chapter, we investigate the dependence of the Yang-Mills wave functional in Coulomb gauge on the Faddeev-Popov determinant. (orig.)

Plasma sintering of ferritic steel reinforced with niobium carbide prepared by high energy milling

International Nuclear Information System (INIS)

Silva Junior, J.F. da; Almeida, E.O.; Gomes, U.U.; Alves Junior, C.; Messias, A.P.; Universidade Federal do Rio Grande do Norte

2010-01-01

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)

77 FR 58120 - Inman Mills; Notice of Authorization for Continued Project Operation

Science.gov (United States)

2012-09-19

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 4362-000] Inman Mills... for a subsequent license was August 31, 2010. Inman Mills, the licensee for Project No. 4362, did not... the license from Inman Mills to Riverdale Development Venture, LLC. 115 FERC ] 62,076 (2006). However...

Scale-up of organic reactions in ball mills: process intensification with regard to energy efficiency and economy of scale.

Science.gov (United States)

Stolle, Achim; Schmidt, Robert; Jacob, Katharina

2014-01-01

The scale-up of the Knoevenagel-condensation between vanillin and barbituric acid carried out in planetary ball mills is investigated from an engineering perspective. Generally, the reaction proceeded in the solid state without intermediate melting and afforded selectively only one product. The reaction has been used as a model to analyze the influence and relationship of different parameters related to operation in planetary ball mills. From the viewpoint of technological parameters the milling ball diameter, dMB, the filling degree with respect to the milling balls' packing, ΦMB,packing, and the filling degree of the substrates with respect to the void volume of the milling balls' packing, ΦGS, have been investigated at different reaction scales. It was found that milling balls with small dMB lead to higher yields within shorter reaction time, treaction, or lower rotation frequency, rpm. Thus, the lower limit is set considering the technology which is available for the separation of the milling balls from the product after the reaction. Regarding ΦMB,packing, results indicate that the optimal value is roughly 50% of the total milling beakers' volume, VB,total, independent of the reaction scale or reaction conditions. Thus, 30% of VB,total are taken by the milling balls. Increase of the initial batch sizes changes ΦGS significantly. However, within the investigated parameter range no negative influence on the yield was observed. Up to 50% of VB,total can be taken over by the substrates in addition to 30% for the total milling ball volume. Scale-up factors of 15 and 11 were realized considering the amount of substrates and the reactor volume, respectively. Beside technological parameters, variables which influence the process itself, treaction and rpm, were investigated also. Variation of those allowed to fine-tune the reaction conditions in order to maximize the yield and minimize the energy intensity.

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.

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

Utilization of aluminum to obtaining a duplex type stainless steel using high energy ball milling

International Nuclear Information System (INIS)

Pavlak, I.E.; Cintho, O.M.; Capocchi, J.D.T.

2010-01-01

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)

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.

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)

Contact angle dependence on the fluid-wall dispersive energy

NARCIS (Netherlands)

Horsch, M.; Heitzig, M.; Dan, C.M.; Harting, J.D.R.; Hasse, H.; Vrabec, J.

2010-01-01

Menisci of the truncated and shifted Lennard-Jones fluid between parallel planar walls are investigated by molecular dynamics simulation. Thereby, the characteristic energy of the unlike dispersive interaction between fluid molecules and wall atoms is systematically varied to determine its influence

Morphology and magnetic properties of CeCo5 submicron flakes prepared by surfactant-assisted high-energy ball milling

International Nuclear Information System (INIS)

Zhang, J.J.; Gao, H.M.; Yan, Y.; Bai, X.; Su, F.; Wang, W.Q.; Du, X.B.

2012-01-01

CeCo 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 α-cyanoacrylate. Scanning electron microscope pictures show that the particles are flakes, several μm 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: ► CeCo 5 permanent magnetic alloy has been processed by surfactant assisted high energy ball milling (HEBM). ► The particles show a flake-like morphology with several μm in length and width and tens nm in thickness. ► 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. ► Maximum coercivity of 3.3 kOe has been obtained for the sample milled for 40 min.

Hydrology and geochemistry of the uranium mill tailings pile at Riverton, Wyoming. Part II. History matching

International Nuclear Information System (INIS)

Narasimhan, T.N.; White, A.F.; Tokunaga, T.

1985-02-01

In Part I of this series of two reports the observed fluid potential and geochemical characteristics in and around the inactive uranium mill tailings pile at Riverton, Wyoming were presented. The prupose of the present work is to attempt to simulate field observations using mathematical models. The results of the studies have not only helped identify the physicochemical mechanisms govering contaminant migration around the inactive mill tailings pile in Riverton, but also have indicated the feasibility of quantifying these mechanisms with the help of newly developed mathematical models. Much work needs to be done to validate and benchmark these models. The history-matching effort on hand involves the mathematical simulation of the observed fluid potentials within the tailings, and the observed distribution of various chemical species within and around the inactive uranium mill tailings. The simulation problem involves consideration of transient fluid flow and transient, reactive chemical transport in a variably saturated ground water system with time-dependent boundary conditions. 15 refs., 30 figs., 3 tabs

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.

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.

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.

Swedish Pulp Mill Biorefineries. A vision of future possibilities

Energy Technology Data Exchange (ETDEWEB)

Berntsson, Thore (Chamers Univ. of Technology, Goeteborg (Sweden)); Axegaard, Peter; Backlund, Birgit; Samuelsson, Aasa; Berglin, Niklas; Lindgren, Karin (STFI-Packforsk, Stockholm (Sweden))

2008-07-01

Today, modern science could make it possible to develop techniques for refining almost the whole wood-matter, pulp mill side streams and bark compounds into platform chemicals, electricity, high quality fuels and structured feed-stock for chemicals and materials. The major challenge is to convert the state of basic scientific knowledge into industrial practise. Our definition of an integrated biorefinery is: 'Full utilization of the incoming biomass and other raw materials for simultaneous and economically optimized production of fibres, chemicals and energy'. Examples of products from a pulp mill biorefinery are: Chemicals and Materials (Phenols, adhesives, carbon fibres, activated carbon, binders, barriers, adhesives, antioxidants, surfactants, chelants, solvents, adhesives surfactants, descaling agents, specialty polymers, pharmaceuticals, nutraceuticals, cosmetics etc., Biofuels (pellets, lignin fuel, methanol, DME, ethanol etc), Electricity (BLGCC, condensing power etc.). The new or increased amounts of traditional products can be made from internal and/or external biomass. Three different levels can be identified: A high degree of energy saving in future mills, especially chemical pulp mills, will lead to large amounts of excess internal biomass which can be transferred to products mentioned above, Components in e.g. the black liquor, forest residues and bark can be upgraded to more valuable ones and the energy balance of the mill is kept through fuel import, wholly or partly depending on the level of mill energy efficiency. This imported fuel can be biomass or other types. External (imported) biomass (in some cases together with excess internal biomass) can be upgraded using synergy effects of docking this upgrading to a pulp mill. Electricity has been included as one of the possible biorefinery products. The electricity production in a mill can be increased in several ways which cannot be directly considered as biorefineries, e.g. recovery boiler

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)

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.

Model Predictive Control for an Industrial SAG Mill

DEFF Research Database (Denmark)

Ohan, Valeriu; Steinke, Florian; Metzger, Michael

2012-01-01

identication. When applied to MIMO systems we call this controller a MIMO-ARX based MPC. We use an industrial Semi-Autogenous Grinding (SAG) mill to illustrate the performance of this controller. SAG mills are the primary units in a grinding chain and also the most power consuming units. Therefore, improved...... control of SAG mills has the potential to signicantly improve eciency and reduce the specic energy consumption for mineral processes. Grinding circuits involving SAG mills are multivariate processes. Commissioning of a control system based on a classical single-loop controllers with logic is time...

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.

Phase transition of Ni-Mn-Ga alloy powders prepared by vibration ball milling

International Nuclear Information System (INIS)

Tian, B.; Chen, F.; Tong, Y.X.; Li, L.; Zheng, Y.F.; Liu, Y.; Li, Q.Z.

2011-01-01

Research highlights: → The vibration ball milling with a high milling energy introduces the atomic disorder and large lattice distortion in the alloy during milling and makes the formation of disordered fcc structure phase in the alloy. → The transition temperature and activation energy for disordered fcc → disordered bcc are ∼320 o C and 209 ± 8 kJ/mol, respectively. → The alloy powders annealed at 800 o C for 1 h show a one-stage martensitic transformation with quite lower latent heat compared to the bulk alloy. - Abstract: This study investigated the phase transformation of the flaky shaped Ni-Mn-Ga powder particles with thickness around 1 μm prepared by vibration ball milling and post-annealing. The SEM, XRD, DSC and ac magnetic susceptibility measurement techniques were used to characterize the Ni-Mn-Ga powders. The structural transition of Heusler → disordered fcc occurred in the powders prepared by vibration ball milling (high milling energy) for 4 h, which was different from the structural transition of Heusler → disordered fct of the powders fabricated by planetary ball milling (low milling energy) for 4 h. The two different structures after ball milling should be due to the larger lattice distortion occurred in the vibration ball milling process than in the planetary ball milling process. The structural transition of disordered fcc → disordered bcc took place at ∼320 o C during heating the as-milled Ni-Mn-Ga powders, which was attributed to the elimination of lattice distortion caused by ball milling. The activation energy for this transition was 209 ± 8 kJ/mol. The Ni-Mn-Ga powder annealed at 800 o C mainly contained Heusler austenite phase at room temperature and showed a low volume of martensitic transformation upon cooling. The inhibition of martensitic transformation might be attributed to the reduction of grain size in the annealed Ni-Mn-Ga particles.

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)

Does intra-abdominal fluid increase the resting energy expenditure?

Science.gov (United States)

Zarling, E J; Grande, A; Hano, J

1997-10-01

In patients with intra-abdominal fluid collection, caloric needs are based on an estimated dry weight. This is done because intra-abdominal fluid has been assumed to be metabolically inactive. One recent study of patients with slowly resolving ascites suggested otherwise. In our study, the effect of intra-abdominal fluid on the resting energy expenditure (REE) and apparent lean body mass was determined in 10 stable patients requiring peritoneal dialysis. For each subject, in both the empty and full state, we measured REE by indirect calorimetry, and body composition by the bioelectric impedance method. In the full state, the VCO2 was significantly increased (210 +/- 11 versus 197 +/- 9 mL/min, P empty state. This caused an increase in the calculated resting energy expenditure (1531 +/- 88 kcal/d empty versus 1593 +/- 94 kcal/d full, P calories derived from glucose absorbed out of the dialysate. Estimates of body fat, lean body mass, and total water also were not affected by the intra-abdominal fluid. We conclude that intra-abdominal fluid will not affect the measured REE and hence may be considered to be metabolically inactive.

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....... The canted spin configuration is also suggested by the observed reduction in magnetization of particles in the blocked state. Upon increasing the milling time, nanometer-sized CuFe2O4 particles decompose, forming alpha-Fe2O3 and other phases, causing a further decrease of magnetization. After a milling time...... of 98 h, alpha-Fe2O3 is reduced to Fe3O4, and magnetization increases accordingly to the higher saturation magnetization value of magnetite. Three sequential processes during high-energy ball milling are established: (a) the synthesis of partially inverted CuFe2O4 particles with a noncollinear spin...

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.

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.

Influence of octanoic acid on SmCo{sub 5} nanoflakes prepared by surfactant-assisted high-energy ball milling

Energy Technology Data Exchange (ETDEWEB)

Zheng Liyun, E-mail: zheng@udel.ed [Department of Physics and Astronomy, University of Delaware, Newark, DE 19716 (United States); College of Electromechanical Engineering, Hebei University of Engineering, Handan, Hebei 056038 (China); Cui Baozhi; Akdogan, Nilay G.; Li Wanfeng; Hadjipanayis, George C. [Department of Physics and Astronomy, University of Delaware, Newark, DE 19716 (United States)

2010-08-20

High-energy ball milling (HEBM) of magnetically hard SmCo{sub 5} was conducted in heptane with octanoic acid as the surfactant. The effects of octanoic acid on the morphology and magnetic properties of the powders were investigated by scanning electron microscopy, X-ray diffraction and vibrating sample magnetometry. The results show an interesting unexpected fact that the SmCo{sub 5} powders processed by octanoic acid-assisted HEBM were in form of nanoflakes with aspect-ratio of 10{sup 2}-10{sup 3} without the presence of nanoparticles. The thickness of nanoflakes decreases with increasing milling time. X-ray diffraction patterns did not show the sign of oxidation and the diffraction peaks of SmCo{sub 5} were getting broader with the increase of milling time. The nanoflakes were magnetically anisotropic and had a higher coercivity than the micro-particles prepared by HEBM without surfactant. The coercivity of SmCo{sub 5} increased initially with the milling time and then it decreased after reaching the maximum value of 15.2 kOe. High-resolution transmission electron microscopy image showed that the SmCo{sub 5} nanoflakes are nanocrystalline with an average crystallite size approximately 12 nm.

Investigation of planetary milling for nano-silicon carbide reinforced aluminium metal matrix composites

Energy Technology Data Exchange (ETDEWEB)

Kollo, Lauri, E-mail: lauri.kollo@staff.ttu.e [Laboratory of Advanced Materials Processing, EMPA, Feuerwerkerstrasse 39, 3602 Thun (Switzerland); Department of Materials Engineering, Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn (Estonia); Leparoux, Marc; Bradbury, Christopher R.; Jaeggi, Christian [Laboratory of Advanced Materials Processing, EMPA, Feuerwerkerstrasse 39, 3602 Thun (Switzerland); Carreno-Morelli, Efrain; Rodriguez-Arbaizar, Mikel [University of Applied Sciences of Western Switzerland, Design and Materials Unit, 1950 Sion (Switzerland)

2010-01-21

High-energy planetary milling was used for mixing aluminium powders with 1 vol.% of silicon carbide (SiC) nanoparticles. A number of milling parameters were modified for constituting the relationship between the energy input from the balls and the hardness of the bulk nanocomposite materials. It was shown that mixing characteristics and reaction kinetics with stearic acid as process control agent can be estimated by normalised input energy from the milling bodies. For this, the additional parameter characterising the vial filling was determined experimentally. Depending on the ball size, a local minimum in filling parameter was found, laying at 25 or 42% filling of the vial volume for the balls with diameter of 10 and 20 mm, respectively. These regions should be avoided to achieve the highest milling efficiency.After a hot compaction, fourfold difference of hardness for different milling conditions was detected. Therewith the hardness of the Al-1 vol.% nanoSiC composite could be increased from 47 HV{sub 0.5} of pure aluminium to 163 HV{sub 0.5} when milling at the highest input energy levels.

Potential Co-Generation of Electrical Energy from Mill Waste: A Case Study of the Malaysian Furniture Manufacturing Industry

Directory of Open Access Journals (Sweden)

Jegatheswaran Ratnasingam

2016-04-01

Full Text Available Furniture manufacturing in Malaysia is an established industry driven primarily by the availability of raw materials and labor. However, the industry suffers from the low-recovery rate of its materials, as it produces a substantial amount of waste during the manufacturing process. Although smaller waste fragments, or off-cuts, are recovered for other purposes, the splinters, shavings, and coarse dust have little economic value and are often discarded. Because wood is a well-established source of bioenergy, this study investigated the potential use of mill waste from the furniture-manufacturing industry for electrical energy generation. Waste from the rubberwood, bamboo, and rattan furniture industries was evaluated for its potential electrical energy generation, and the amount was compared with the electrical energy that was consumed by the furniture industry. The study also compared the emission of greenhouse gases from the combustion of these waste materials against fossil fuels used to generate electricity to assess its potential in terms of the environmental benefits. In conclusion, such mill waste could be utilized as substitute for fossil fuel to generate energy in the furniture industry.

Cosmological models described by a mixture of van der Waals fluid and dark energy

International Nuclear Information System (INIS)

Kremer, G.M.

2003-01-01

The Universe is modeled as a binary mixture whose constituents are described by a van der Waals fluid and by a dark energy density. The dark energy density is considered either as quintessence or as the Chaplygin gas. The irreversible processes concerning the energy transfer between the van der Waals fluid and the gravitational field are taken into account. This model can simulate (a) an inflationary period where the acceleration grows exponentially and the van der Waals fluid behaves like an inflaton, (b) an accelerated period where the acceleration is positive but it decreases and tends to zero whereas the energy density of the van der Waals fluid decays, (c) a decelerated period which corresponds to a matter dominated period with a non-negative pressure, and (d) a present accelerated period where the dark energy density outweighs the energy density of the van der Waals fluid

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

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)

Infrared finiteness in Yang--Mills theories

International Nuclear Information System (INIS)

Appelquist, T.; Carazzone, J.; Kluberg-Stern, H.; Roth, M.

1976-01-01

The infrared divergences of renormalizable theories with coupled massless fields (in particular, the Yang--Mills theory) are shown to cancel for transition probabilities corresponding to finite-energy-resolution detectors, just as in quantum electrodynamics. This result is established through lowest nontrivial order in perturbation theory for the detection of massive muons in a quantum electrodynamic theory containing massless electrons or the detection of massive quarks in a Yang--Mills theory

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.

Uranium mill tailings remedial action technology

International Nuclear Information System (INIS)

Hartley, J.N.; Gee, G.W.

1984-01-01

The uranium milling process involves the hydrometallurgical extraction of uranium from ores and the resultant generation of large quantities of waste referred to as tailings. Uranium mill tailings have been identified as requiring remediation because they contain residual radioactive material that is not removed in the milling process. Potential radiation exposure can result from direct contact with the tailings, from radon gas emitted by the tailings, and from radioactive contamination of groundwater. As a result, the technology developed under the US Department of Energy (DOE) Uranium Mill Tailings Remedial Action Project (UMTRAP) and the US Nuclear Regulatory Commission (NRC) Uranium Recovery Program have focused on radon control, groundwater contamination and the long-term protection of the containment system. This paper briefly summarizes the UMTRAP and NRC remedial action technology development. 33 references, 9 figures, 5 tables

Rock Characteristics and Ball Mill Energy Requirements at ...

African Journals Online (AJOL)

These changes can have great impact on milling operations. ... Goldfields Ghana Limited, Tarkwa Gold Mine (TGM), processes ores which occur in ... The parameters examined had deviated from the design; Work Index (WI) for example was ...

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.

The Taylor-Proudman column in a rapidly-rotating compressible fluid I. energy transports

International Nuclear Information System (INIS)

Park, Jun Sang

2014-01-01

A theoretical study is made of the steady flow of a compressible fluid in a rapidly rotating finite cylinder. Flow is generated by imposing mechanical and/or thermal disturbances at the rotating endwall disks. Both the Ekman and Rossby numbers are small. An examination is made of the energy budget for a control volume in the Ekman boundary layer. A combination of physical variables, which is termed the energy flux content, consisting of temperature and modified angular momentum, emerges to be relevant. The distinguishing features of a compressible fluid, in contrast to those of an incompressible fluid, are noted. A plausible argument is given to explain the difficulty in achieving the Taylor-Proudman column in a compressible rotating fluid. For the Taylor-Proudman column to be sustained, in the interior, it is shown that the net energy transport between the solid disk wall and the interior fluid should vanish. Physical rationalizations are facilitated by resorting to the concept of the afore-stated energy flux content.

Effect of the milling conditions on the degree of amorphization of selenium by milling in a planetary ball mill

International Nuclear Information System (INIS)

Ksiazek, K; Wacke, S; Gorecki, T; Gorecki, Cz

2007-01-01

The effect of the milling parameters (rotation speed of the milling device and duration of milling) on the phase composition of the products of milling of fully crystalline selenium has been investigated. The milling was conducted using a planetary micromill and the phase composition of the milling products was determined by differential thermal analysis. It has been found that ball milling leads to the partial amorphization of the starting crystalline material. The content of amorphous phase in the milling products depends, in a rather complicated way, on the milling parameters. At the milling parameters adopted in the present study, the milling product was never fully amorphous. The complicated way the milling parameters affect the content of amorphous phase in the milling products is a result of competition of two processes: amorphization due to deformation and refinement of grains of milled material and crystallization of the already produced amorphous material at the cost of heat evolved in the milling vial during the milling process

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

75 FR 11149 - Bowersock Mills and Power Company; Notice of Application Tendered for Filing With the Commission...

Science.gov (United States)

2010-03-10

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 13526-001] Bowersock Mills...: Bowersock Mills Power Company (Bowersock). e. Name of Project: Bowersock Mills and Power Company Expanded....S.C. 791(a)-825(r). h. Applicant Contact: Sarah Hill-Nelson, The Bowersock Mills and Power Company...

77 FR 35431 - Final Alternative Soils Standards for the Uravan, CO, Uranium Mill

Science.gov (United States)

2012-06-13

..., Uranium Mill AGENCY: Nuclear Regulatory Commission. ACTION: Notice of Uranium milling alternative... amend their agreements to regulate uranium mill tailings (11e.(2) byproduct material). Six Agreement... transferring the Uravan uranium mill site to the U.S. Department of Energy. The NRC staff found no deficiencies...

Holographic dark energy from fluid/gravity duality constraint by cosmological observations

Science.gov (United States)

Pourhassan, Behnam; Bonilla, Alexander; Faizal, Mir; Abreu, Everton M. C.

2018-06-01

In this paper, we obtain a holographic model of dark energy using the fluid/gravity duality. This model will be dual to a higher dimensional Schwarzschild black hole, and we would use fluid/gravity duality to relate to the parameters of this black hole to such a cosmological model. We will also analyze the thermodynamics of such a solution, and discuss the stability model. Finally, we use cosmological data to constraint the parametric space of this dark energy model. Thus, we will use observational data to perform cosmography for this holographic model based on fluid/gravity duality.

Magneto-optical properties of α-Fe2O3@ZnO nanocomposites prepared by the high energy ball-milling technique

Science.gov (United States)

Chaudhury, Chandana Roy; Roychowdhury, Anirban; Das, Anusree; Das, Dipankar

2016-05-01

Magnetic-fluorescent nanocomposites (NCs) with 10 wt% of α-Fe2O3 in ZnO have been prepared by the high energy ball-milling. The crystallite sizes of α-Fe2O3 and ZnO in the NCs are found to vary from 65 nm to 20 nm and 47 nm to 15 nm respectively as milling time is increased from 2 to 30 h. XRD analysis confirms presence of α-Fe2O3 and ZnO in pure form in all the NCs. UV-vis study of the NCs shows a continuous blue-shift of the absorption peak and a steady increase of band gap of ZnO with increasing milling duration that are assigned to decreasing particle size of ZnO in the NCs. Photoluminescence (PL) spectra of the NCs reveal three weak emission bands in the visible region at 421, 445 and 485 nm along with the strong near band edge emission at 391 nm. These weak emission bands are attributed to different defect - related energy levels e.g. Zn-vacancy, Zn interstitial and oxygen vacancy. Dc and ac magnetization measurements show presence of weakly interacting superparamagnetic (SPM) α-Fe2O3 particles in the NCs. 57Fe-Mössbauer study confirms presence of SPM hematite in the sample milled for 30 h. Positron annihilation lifetime measurements indicate presence of cation vacancies in ZnO nanostructures confirming results of PL studies.

On the closed form mechanistic modeling of milling: Specific cutting energy, torque, and power

Science.gov (United States)

Bayoumi, A. E.; Yücesan, G.; Hutton, D. V.

1994-02-01

Specific energy in metal cutting, defined as the energy expended in removing a unit volume of workpiece material, is formulated and determined using a previously developed closed form mechanistic force model for milling operations. Cutting power is computed from the cutting torque, cutting force, kinematics of the cutter, and the volumetric material removal rate. Closed form expressions for specific cutting energy were formulated and found to be functions of the process parameters: pressure and friction for both rake and flank surfaces and chip flow angle at the rake face of the tool. Friction is found to play a very important role in cutting torque and power. Experiments were carried out to determine the effects of feedrate, cutting speed, workpiece material, and flank wear land width on specific cutting energy. It was found that the specific cutting energy increases with a decrease in the chip thickness and with an increase in flank wear land.

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....

Wood pellet milling tests in a suspension-fired power plant

DEFF Research Database (Denmark)

Masche, Marvin; Puig-Arnavat, Maria; Wadenbäck, Johan

2018-01-01

classification (i.e., the classifier cut size) are affected by the internal pellet particle size distribution obtained after pellet disintegration in hot water. Furthermore, optimal conditions for comminuting pellets were identified. The milling behavior was assessed by determining the specific grinding energy...... consumption and the differential mill pressure. The size and shape of comminuted pellets sampled from burner pipes were analyzed by dynamic image analysis and sieve analysis, respectively. The results showed that the internal pellet particle size distribution affected both the milling behavior...... similar. Mill operating changes had a negligible effect on the original elongated wood particle shape. To achieve the desired comminuted product fineness (i.e., the classifier cut size) with lower specific grinding energy consumption, power plant operators need to choose pellets with a finer internal...

Critical phenomena and their effect on thermal energy storage in supercritical fluids

International Nuclear Information System (INIS)

Hobold, Gustavo M.; Da Silva, Alexandre K.

2017-01-01

Highlights: •High power thermal energy storage using supercritical fluids. •Influence of property variation on energy and power density. •Multi-fluid analysis and generalization for several storage temperatures. •Cost, heat transfer and energy density evaluation for high temperature storage. -- Abstract: Large-scale implementation of concentrated solar power plants requires energy storage systems if fossil sources are to be fully replaced. While several candidates have appeared, most still face major issues such as cost, limited energy density and material compatibility. The present paper explores the influence of property variation in the proximity of the critical point on thermal energy storage using supercritical fluids (sTES) from thermodynamic and heat transfer standpoints. Influence of thermodynamic operational parameters on energy density of isobaric and isochoric sTES and their optima is discussed, showing that the energy density results from a competition between average specific heat and loaded density. Moreover, sTES is shown to be applicable to virtually any storage temperature, depending only on the fluid’s critical point. Finally, a heat transfer and energy density comparison to other existing storage mechanisms is presented and supercritical water is shown to be competitive for high temperature thermal energy storage.

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)

75 FR 16449 - Dodge Mill Reality LLC; Notice of Declaration of Intention and Soliciting Comments, Protests, and...

Science.gov (United States)

2010-04-01

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. DI10-10-000] Dodge Mill...-10-000. c. Date Filed: March 8, 2010. d. Applicant: Dodge Mill Reality LLC. e. Name of Project... of: (1) An existing 275-acre-foot mill pond; (2) an existing 20-foot-high, 400-foot-long earthen mill...

Hydrothermal alterations and O, H, C isotopic characterization of fluids and minerals in uraniferous massif of Saint Sylvestre (France). Extension to other French intragranitic uranium deposits

International Nuclear Information System (INIS)

Turpin, L.

1984-05-01

Petrographical, mineralogical, geochemical and stable isotope ( 18 O/ 16 O, D/H, 13 C/ 12 C) studies have been performed on the leucogranitic massif of St Sylvestre (Limousin, Massif Central francais), particularly on the different hydrothermal alterations. The oxygen isotope geochemistry of granites confirms the unicity of the different facies and their sialic origin (delta 18 O whole rocks = +11.0 +- 0.5 per mill), with a major contribution of detritic sediments rich in organic matter and poor in carbonate (delta 13 C magm. CO 2 = -10.6 per mill). Late lamprophyres have a deep-seated origin (delta 18 O = + 6 per mill). The pervasive chloritization of granitic biotites occurs during the convective circulation of a fluid of meteoric origin, at temperatures around 350-450 0 C. The chemical composition of chlorite which is buffered by that of biotite and the large 18 O-shift of fluid towards high delta values indicate that water-rock ratio was not very high. Chloritization takes place in high permeability zones. In regions where porosity is generally low, fluids are ''canalised'' in localised micro-fissured zones. Very high water/rock ratios lead to the dissolution of quartz, and the formation of the ''feldspathic episyenite'' alteration facies. The isotopic features of this fluid (delta 18 O approximately - 8 per mill, deltaD approximately - 50 per mill) indicate an elevated altitude. An isotopically similar fluid is responsible for the later ''micaceous episyenite'' alteration facies, found in fractured zones. Mixing of this fluid with a sedimentary fluid (delta 18 O approximately + 10 per mill, deltaD approximately - 30 per mill, delta 13 C approximately - 18 per mill) yielded the conditions necessary for the deposit of primary economic ore. Such fluids, sedimentary or metamorphic in origin, have been recognized in most hercynian intragranitic U and Sn-W deposits [fr

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

75 FR 11153 - Main Mill Street Investments, LLC; Notice of Preliminary Permit Application Accepted for Filing...

Science.gov (United States)

2010-03-10

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 13631-000] Main Mill Street..., Motions To Intervene, and Competing Applications March 1, 2010. On November 16, Main Mill Street Investments, LLC (Main Mill Street Investments) filed an application for a preliminary permit, pursuant to...

75 FR 21286 - Bowersock Mills and Power Company; Notice of Application Accepted for Filing, Soliciting Motions...

Science.gov (United States)

2010-04-23

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 13526-002] Bowersock Mills... License. b. Project No.: 13526-002. c. Date Filed: February 8, 2010. d. Applicant: Bowersock Mills Power Company (Bowersock). e. Name of Project: Bowersock Mills and Power Company Expanded Kansas River...

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.

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.

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.

Complex Fluids in Energy Dissipating Systems

Directory of Open Access Journals (Sweden)

Francisco J. Galindo-Rosales

2016-07-01

Full Text Available The development of engineered systems for energy dissipation (or absorption during impacts or vibrations is an increasing need in our society, mainly for human protection applications, but also for ensuring the right performance of different sort of devices, facilities or installations. In the last decade, new energy dissipating composites based on the use of certain complex fluids have flourished, due to their non-linear relationship between stress and strain rate depending on the flow/field configuration. This manuscript intends to review the different approaches reported in the literature, analyses the fundamental physics behind them and assess their pros and cons from the perspective of their practical applications.

Attritor milling of WC + 6% Co: Effects on powder characteristics and compaction behavior

International Nuclear Information System (INIS)

Mashl, S.J.; Smith, D.W.; Becking, G.H.; Hale, T.E.

1987-01-01

This study examines the effects of attritor milling on the characteristics and bulk behavior of fine tungsten carbide powders (initial median particle size ≅ 1.5 μm) blended with 6 wt. % cobalt (mps ≅ 1.5 μm). Experiments are performed in order to: Develop a process model relating the specific energy input to the milled median particle size. Examine the effect that changes in milling variables have on the specific energy - median particle size relationship. Observe the effects of variation in the initial particle size distribution on the as-milled particle size distribution, the compaction characteristics of the powder, and the shrinkage which will occur during sintering. The process model is based on Charles' equation, E-bar = A (d/sup -α/ - d/sub o//sup -α/) in which E-bar = the specific energy consumed in milling, d and d = the initial and milled median particle sizes respectively, and A and α are constants. Computer curve fitting techniques are employed to determine the values of the coefficient and exponent in the above equation. The resulting model predicts the experimental data within about +- over 10% over a significant range of d/sub o/ and E-Bar values. The apparent density and compactibility of the attritor milled powders are observed to be very sensitive to the milled particle size distribution

Energy transport in cooling device by magnetic fluid

Energy Technology Data Exchange (ETDEWEB)

Yamaguchi, Hiroshi, E-mail: hyamaguc@mail.doshisha.ac.jp [Department of Mechanical Engineering, Doshisha University, Kyo-tanabe, Kyoto 610-0321 (Japan); Iwamoto, Yuhiro [Department of Electrical and Mechanical Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya, Aichi 466-8555 (Japan)

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. - 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.

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.

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

International Nuclear Information System (INIS)

1995-01-01

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

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.

CONSIDERATIONS ON FLUID DYNAMICS INSIDE A HYDRAULIC SEISMIC ENERGY ABSORBER

Directory of Open Access Journals (Sweden)

ȘCHEAUA Fănel

2013-06-01

Full Text Available This study presents a method for obtaining a simplified model of a seismic energy dissipation device whose operating principle is based on viscous fluid as a solution for structural isolation against seismic actions. The device operation is based on the resistance force developed by the working fluid when the piston tends to move due to occurrence of a seismic motion. A 3D model achieved is introduced in CFD analysis for emphasize dynamic fluid flow inside the device dissipation cylinder.

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

Enhancing thermal conductivity of fluids with graphite nanoparticles and carbon nanotube

Science.gov (United States)

Zhang, Zhiqiang [Lexington, KY; Lockwood, Frances E [Georgetown, KY

2008-03-25

A fluid media such as oil or water, and a selected effective amount of carbon nanomaterials necessary to enhance the thermal conductivity of the fluid. One of the preferred carbon nanomaterials is a high thermal conductivity graphite, exceeding that of the neat fluid to be dispersed therein in thermal conductivity, and ground, milled, or naturally prepared with mean particle size less than 500 nm, and preferably less than 200 nm, and most preferably less than 100 nm. The graphite is dispersed in the fluid by one or more of various methods, including ultrasonication, milling, and chemical dispersion. Carbon nanotubes with graphitic structure is another preferred source of carbon nanomaterial, although other carbon nanomaterials are acceptable. To confer long term stability, the use of one or more chemical dispersants is preferred. The thermal conductivity enhancement, compared to the fluid without carbon nanomaterial, is proportional to the amount of carbon nanomaterials (carbon nanotubes and/or graphite) added.

Polycrystalline Nd2Fe14B/α-Fe nanocomposite flakes with a sub-micro/nanometre thickness prepared by surfactant-assisted high-energy ball milling

International Nuclear Information System (INIS)

Tang, Xin; Chen, Xi; Chen, Renjie; Yan, Aru

2015-01-01

Highlights: • Nd 2 Fe 14 B/α-Fe flakes are formed by peeling along preferential planes. • (0 0 l) planes are found to be preferential cleavage planes. • Magnetic properties degrade with increasing ball milling time. • Anisotropic nanocomposite magnets are fabricated. - Abstract: A surfactant-assisted high-energy ball milling technique was employed to synthesize Nd 2 Fe 14 B/α-Fe nanoparticles and nanoflakes from melt-spun nanocrystalline powders. The microstructure evolution in ball milling process was investigated. In the beginning stage (0–4 h) of ball milling, raw powders were crushed into micrometre-sized particles. While flakes were mainly formed by reducing thickness of particles via peeling layer by layer along preferential planes in the late stage (8–16 h). The selected area electron diffraction and high-resolution transmission electron microscopy images show that preferential cleavage planes are basal planes. With ball milling proceeding, more and more defects were induced by ball milling. As a result, the coercivity and remanence decreased to 1.6 kOe and 3.2 kGs, respectively. After 16 h ball milling, the exchange decoupling occurred due to severe amorphorization. A weakly-textured nanocomposite magnet was fabricated after 12 h ball milling and the anisotropy in magnetic properties can be further improved by employing settling down process to select particle size and aligning particles in external field

Effect of ball mill treatment on kinetics of amorphous Ni78Si10B12 alloy crystallization

International Nuclear Information System (INIS)

Tomilin, I.A.; Mochalova, T.Yu.; Kaloshkin, S.D.; Kostyukovich, T.G.; Lopatina, E.A.

1993-01-01

The effect of the parameters of Ni 78 Si 10 B 12 alloy amorphous strip milling in a ball planetary mill on the stability of powder amorphous state, crytallization kinetics and dispersity is studied by the methods of differential scanning microcaloremetry and X-ray diffraction analysis. Energy intensity of milling conditions is assessed. An increase of input energy results in a decrease of activation energy of powder crystallization. Strip milling parameters which enable to avaintain the amorphous state of the material are determined

Study of the viability to obtain quasicrystal in the composition AlCuFe using high-energy milling, followed by pressing and sintering

International Nuclear Information System (INIS)

Coelho, Rodrigo Estevam; Cruz, Ramon Mateus Santos; Esteves, Paulo Jesus Costa; Viana, Silvana Garcia; Lima, Severino Jackson Guedes de

2009-01-01

This work was observed the phase formations of the mixture Al-Cu-Fe processed vial mechanical alloying, powders pressing at room temperature and subsequent heat treatment. The mixture of powders was made on the nominal composition Al 65 Cu 2 0Fe 15 . A mill of high energy of the horizontal atrittor type was used to process the powders mixtures, in fixed time of two hours of milling. After milling, the powders were pressing in a die closed, with a diameter of about 28mm. The samples were observed by optical microscopy and analyzed X-ray diffractometry. The results obtained in this study provide a basis for setting parameters may be used as a basis for future research and possible applications. (author)

Uranium milling costs

International Nuclear Information System (INIS)

Coleman, R.B.

1980-01-01

Basic process flowsheets are reviewed for conventional milling of US ores. Capital costs are presented for various mill capacities for one of the basic processes. Operating costs are shown for various mill capacities for all of the basic process flowsheets. The number of mills using, or planning to use, a particular process is reviewed. A summary of the estimated average milling costs for all operating US mills is shown

The effect of surfactant addition on high-energy milling upon the magnetic properties and microstructure of the Pr-Fe-B HDDR magnetic powders

International Nuclear Information System (INIS)

Santos, P.B.; Silva, S.C.; Faria, R.N.; Takiishia, H.

2010-01-01

Nanomagnetic powders based on the composition Pr 12 Fe 65.9 Co 16 B 6 Nb 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)

Multi-physics modeling of large ring motor for mining industry - Combining electromagnetism, fluid mechanics, mass and heat transfer in engineering design

DEFF Research Database (Denmark)

Andersen, Søren Bøgh; Santos, Ilmar F.; Fuerst, Axel

2015-01-01

This paper presents an improved completely interconnected procedure for estimating the losses, cooling flows, fluid characteristics and temperature distribution in a gearless mill drive using real life data. The presented model is part of a larger project building a multi-physics model combining...... iteratively according to the heat flux transferred to the fluid, is modeled as a lumped model with two nodes interconnected by 11 channels and one pump. The flow model is based on Bernoulli's energy equation and solved by Newton-Raphson method. All the results from the three physical areas have been verified...

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.

75 FR 61460 - Avondale Mills Inc.; Augusta Canal Authority; Notice of Application for Transfer of License, and...

Science.gov (United States)

2010-10-05

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 5044-015] Avondale Mills... and Motions To Intervene September 24, 2010. On September 13, 2010, Avondale Mills Inc. (transferor... Mill Project No. 5044, located on the Augusta Canal in the City of Augusta, Richmond County, Georgia...

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

Influence of minimum quantity of lubricant (MQL on tool life of carbide cutting tools during milling process of steel AISI 1018

Directory of Open Access Journals (Sweden)

Diego Núñez

2017-03-01

Full Text Available Nowadays, high productivity of machining is an important issue to obtain economic benefits in the industry. This purpose could be reached with high cutting velocity and feed rate. However, the inherently behavior produce high temperatures in the interface of couple cutting tool/workpiece. Many cutting fluids have been developed to control temperature in process and increase tool life. The objective of this paper is to compare the carbide milling tool wear using different systems cutting fluids: flood and minimum quantity of lubrication (MQL. The values of carbide milling cutting tool wear was evaluate according with the standard ISO 8688-1 1989. The experimental results showed that using MQL reduces significantly (about 40% tool wear in milling AISI 1018 steel at industrial cutting conditions.

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)

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)

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)

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.

Production of pyrite nanoparticles using high energy planetary ball milling for sonocatalytic degradation of sulfasalazine.

Science.gov (United States)

Khataee, Alireza; Fathinia, Siavash; Fathinia, Mehrangiz

2017-01-01

Sonocatalytic performance of pyrite nanoparticles was evaluated by the degradation of sulfasalazine (SSZ). Pyrite nanoparticles were produced via a high energy mechanical ball milling (MBM) in different processing time from 2h to 6h, in the constant milling speed of 320rpm. X-ray diffraction (XRD), scanning electron microscopy (SEM) coupled with energy dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FT-IR) analysis and Brunauer-Emmett-Teller (BET) confirmed the production of pyrite nanoparticles during 6h of ball milling with the average size distribution of 20-80nm. The effects of various operational parameters including pH value, catalyst amount (mg/L), SSZ concentration (mg/L), ultrasonic frequency (kHz) and reaction time on the SSZ removal efficiency were examined. The obtained results showed that the maximum removal efficiency of 97.00% was obtained at pH value of 4, catalyst dosage of 0.5g/L, SSZ concentration of 10mg/L and reaction time of 30min. Experimental results demonstrated that the kinetic of the degradation process can be demonstrated using Langmuir-Hinshelwood (L-H) kinetic model. The effect of different inorganic ions such as Cl - , CO 3 2- and SO 4 2- was investigated on the L-H reaction rate (k r ) and adsorption (K s ) constants. Results showed that the presence of the mentioned ions significantly influenced the L-H constants. The impact of ethanol as a OH radical scavenger and some enhancers including H 2 O 2 and K 2 S 2 O 8 was investigated on the SSZ removal efficiency. Accordingly, the presence of ethanol suppressed SSZ degradation due to the quenching of OH radicals and the addition of K 2 S 2 O 8 and H 2 O 2 increased the SSZ removal efficiency, due to the formation of SO 4 - and additional OH radicals, respectively. Under the identical conditions of operating parameters, pyrite nanoparticles maintained their catalytic activity during four consecutive runs. Copyright © 2016 Elsevier B.V. All rights reserved.

75 FR 52523 - Bowersock Mills and Power Company; Notice of Availability of Environmental Assessment

Science.gov (United States)

2010-08-26

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 13526-002-KS] Bowersock Mills and Power Company; Notice of Availability of Environmental Assessment August 19, 2010. In... reviewed the application for an original license for the Bowersock Mills and Power Company's Expanded...

N=4 supersymmetric Yang Mills scattering amplitudes at high energies. The Regge cut contribution

International Nuclear Information System (INIS)

Bartels, J.; Sabio Vera, A.

2008-07-01

We further investigate, in N=4 supersymmetric Yang Mills theories, the high energy Regge behavior of six-point scattering amplitudes. In particular, for the new Regge cut contribution found in our previous paper, we compute in the leading logarithmic approximation (LLA) the energy spectrum of the BFKL equation in the color octet channel, and we calculate explicitly the two loop corrections to the discontinuities of the amplitudes for the transitions 2→4 and 3→3. We find an explicit solution of the BFKL equation for the octet channel for arbitrary momentum transfers and investigate the intercepts of the Regge singularities in this channel. As an important result we find that the universal collinear and infrared singularities of the BDS formula are not affected by this Regge-cut contribution. (orig.)

Dehydriding and re-hydriding properties of high-energy ball milled LiBH{sub 4}+MgH{sub 2} mixtures

Energy Technology Data Exchange (ETDEWEB)

Crosby, Kyle; Shaw, Leon L. [Department of Chemical, Materials and Biomolecular Engineering, University of Connecticut, 97 North Eagleville Road, U-3136, Storrs, CT 06269 (United States)

2010-07-15

Here we report the first investigation of the dehydriding and re-hydriding properties of 2LiBH{sub 4} + MgH{sub 2} mixtures in the solid state. Such a study is made possible by high-energy ball milling of 2LiBH{sub 4}+MgH{sub 2} mixtures at liquid nitrogen temperature with the addition of graphite. The 2LiBH{sub 4}+MgH{sub 2} mixture ball milled under this condition exhibits a 5-fold increase in the released hydrogen at 265 C when compared with ineffectively ball milled counterparts. Furthermore, both LiBH{sub 4} and MgH{sub 2} contribute to hydrogen release in the solid state. The isothermal dehydriding/re-hydriding cycles at 265 C reveal that re-hydriding is dominated by re-hydriding of Mg. These unusual phenomena are explained based on the formation of nanocrystalline and amorphous phases, the increased defect concentration in crystalline compounds, and possible catalytic effects of Mg,MgH{sub 2} and LiBH{sub 4} on their dehydriding and re-hydriding properties. (author)

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.

A volatile fluid assisted thermo-pneumatic liquid metal energy harvester

Energy Technology Data Exchange (ETDEWEB)

Tang, Jianbo, E-mail: zhouyuan@mail.ipc.ac.cn, E-mail: jianbotang@mail.ipc.ac.cn [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Wang, Junjie; Liu, Jing; Zhou, Yuan, E-mail: zhouyuan@mail.ipc.ac.cn, E-mail: jianbotang@mail.ipc.ac.cn [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China)

2016-01-11

A close-cycle self-driving thermal energy harvester using liquid metal as energy carrier fluid has been proposed. The driving force that pushes the liquid metal against flow resistance and gravity is provided by a resistively heated volatile fluid based on thermo-pneumatic principle. The tested harvester prototype demonstrated its capability to extract thermal energy between small temperature gradient, at a scale of 10 °C. During a 5-h operation, it further demonstrated robust liquid metal recirculating performance at a time-average volume flow rate of 14 ml/min with a 12.25 W heating load. The prototype also managed to self-adjust to variable working conditions which indicated the reliability of this method. Advantages of this method include simple-structural design, rigid-motion free operation, and low-temperature actuation. These advantages make it uniquely suited for solar energy and low-grade heat harvesting, high heat flux electronics cooling, as well as autonomous machines actuating.

Saddle point solutions in Yang-Mills-dilaton theory

International Nuclear Information System (INIS)

Bizon, P.

1992-01-01

The coupling of a dilaton to the SU(2)-Yang-Mills field leads to interesting non-perturbative static spherically symmetric solutions which are studied by mixed analytical and numerical methods. In the abelian sector of the theory there are finite-energy magnetic and electric monopole solutions which saturate the Bogomol'nyi bound. In the nonabelian sector there exist a countable family of globally regular solutions which are purely magnetic but have zero Yang-Mills magnetic charge. Their discrete spectrum of energies is bounded from above by the energy of the abelian magnetic monopole with unit magnetic charge. The stability analysis demonstrates that the solutions are saddle points of the energy functional with increasing number of unstable modes. The existence and instability of these solutions are 'explained' by the Morse-theory argument recently proposed by Sudarsky and Wald. (author)

Effects of processing parameters on the synthesis of (K0.5Na0.5)NbO3 nanopowders by reactive high-energy ball milling method.

Science.gov (United States)

Nguyen, Duc Van

2014-01-01

The effects of ball milling parameters, namely, the ball-to-powder mass ratio and milling speed, on the synthesis of (K0.5Na0.5)NbO3 nanopowders by high-energy ball milling method from a stoichiometric mixture containing Na2CO3, K2CO3, and Nb2O5 were investigated in this paper. The results indicated that the single crystalline phase of (K0.5Na0.5)NbO3 was received in as-milled samples synthesized using optimized ball-to-powder mass ratio of 35 : 1 and at a milling speed of 600 rpm for 5 h. In the optimized as-milled samples, no remaining alkali carbonates that can provide the volatilizable potassium-containing species were found and (K0.5Na0.5)NbO3 nanopowders were readily obtained via the formation of an intermediate carbonato complex. This complex was mostly transformed into (K0.5Na0.5)NbO3 at temperature as low as 350°C and its existence was no longer detected at spectroscopic level when calcination temperature crossed over 700°C.

Synthesis of Ni-YSZ cermet for an electrode of high temperature electrolysis by high energy ball milling

International Nuclear Information System (INIS)

Hong, H.S.; Chae, U.S.; Park, K.M.; Choo, S.T.

2005-01-01

Ni/YSZ composites for a cathode that can be used in high temperature electrolysis were prepared by ball milling of Ni and YSZ powder. Ball milling was performed in a dry process and in ethanol. The microstructure and electrical conductivity of the composites were examined by XRD, SEM, TEM and a 4-point probe. XRD patterns for both the dry and wet ball-milled powders showed that the composites were composed of crystalline Ni and YSZ particles. The patterns did not change with increases in the milling time up to 48 h. Dry-milling slightly increased the average particle size compared to starting Ni particles, but little change in the particle size was observed with the increase in milling time. On the other hand, the wet-milling reduced the average size and the increasing milling time induced a further decrease in the particle size. After cold-pressing and annealing at 900 C for 2 h, the dry-milled powder exhibited high stability against Ni sintering so that the particle size changed little, but the particle size increased in the wet-milled powder. The electrical conductivity increased after sintering at 900 C. Particles from the dry and wet process became denser and contacted closer after sintering, providing better electron migration paths. (orig.)

Analysis of crystallite size and microdeformation crystal lattice the tungsten carbide milling in mill high energy; Analise do tamanho do cristalito e microdeformacao da rede cristalina do carbeto de tugstenio moidos em moinho de alta energia

Energy Technology Data Exchange (ETDEWEB)

Silva, F.T. da; Nunes, M.A.M. [Universidade Federal do Rio Grande do Norte (PPGCEM/UFRN), Natal (Brazil). Programa de Pos-Graduacao em Ciencia e Engenharia de Materiais; Oliveira, R.M.V. de; Silva, G.G. da [Instituto Federal do Rio Grande do Norte (IFRN), Natal (Brazil); Souza, C.P. de; Gomes, U.U. [Universidade Federal do Rio Grande do Norte (UFRN), Natal (Brazil)

2010-07-01

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)

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...... simulation program requires a detailed description of the energy flow in the air movement which can be obtained by a CFD program. The paper describes an energy consumption calculation in a large building, where the building energy simulation program is modified by CFD predictions of the flow between three...... zones connected by open areas with pressure and buoyancy driven air flow. The two programs are interconnected in an iterative procedure. The paper shows also an evaluation of the air quality in the main area of the buildings based on CFD predictions. It is shown that an interconnection between a CFD...

Low-temperature magnetic behavior of ball-milled copper ferrite

DEFF Research Database (Denmark)

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

1999-01-01

We present a study on magnetic properties of CuFe2O4 nanoparticles, produced by high-energy ball milling. The series of samples obtained, with average particle sizes LFAN alpha d RTAN ranging from 61 nm to 9 nm, display increasing relaxation effects at room temperature. Irreversibility of the mag......We present a study on magnetic properties of CuFe2O4 nanoparticles, produced by high-energy ball milling. The series of samples obtained, with average particle sizes LFAN alpha d RTAN ranging from 61 nm to 9 nm, display increasing relaxation effects at room temperature. Irreversibility...... of the magnetization and shifts to negative fields in the hysteresis loops are observed below T-f APEQ 55 K, indicating unidirectional magnetic anisotropy in milled samples. These features could be explained by assuming the formation of a spin-disordered surface layer, which is exchange-coupled to the ferrimagnetic...

Uranium Mill Tailings Remedial Action Project: technical approach document

International Nuclear Information System (INIS)

1986-05-01

The Uranium Mill Tailings Radiation Control Act of 1978, PL95-604, grants the Secretary of Energy authority and responsibility to perform such actions as are necessary to minimize radiation health hazards and other environmental hazards from inactive uranium mill sites. These cleanup actions are to be performed in compliance with the EPA standards (40 CFR Part 192) which became final on March 7, 1983. This document describes the general technical approaches and design criteria that are adopted by the US Department of Energy (DOE) in order to implement Remedial Action Plans (RAPs) and final designs that comply with EPA standards

Cogeneration of electric energy: The case of pulp and paper mills

International Nuclear Information System (INIS)

Harberger, A.C.

1993-01-01

Applied welfare economics are utilized to analyze the phenomenon of cogeneration of electricity in the pulp and paper sector. Optimum levels of energy use (and of cogeneration) are defined, and the efficiency costs of various possible deviations from the optimum are shown. An economic analysis is presented of the effects of cost of electricity for the pulp and paper industry, and the impact that cogeneration can have on these costs. The social welfare impacts of cogeneration and electricity subsidies are discussed, together with the issue of crosshauling. It is shown that in Canada a policy focusing on cogeneration without crosshauling leads to optimal results. An added argument against crosshauling involves the implicit transfers involved. These transfers generate benefits for the pulp and paper mills at the expense of the electricity utility and its paying customers or taxpaying public. A strong argument is proposed against allowing of crosshauling

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

Masslessness of ghosts in equivariantly gauge-fixed Yang-Mills theories

International Nuclear Information System (INIS)

Golterman, Maarten; Zimmerman, Leah

2005-01-01

We show that the one-loop ghost self-energy in an equivariantly gauge-fixed Yang-Mills theory vanishes at zero momentum. A ghost mass is forbidden by equivariant BRST symmetry, and our calculation confirms this explicitly. The four-ghost self interaction which appears in the equivariantly gauge-fixed Yang-Mills theory is needed in order to obtain this result

Influence of milling process in the surface energy of glass tile frits; Influencia de la molienda en la energia superficial de fritas para esmaltes

Energy Technology Data Exchange (ETDEWEB)

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

2013-05-01

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{sub 2} by 5% of B{sub 2}O{sub 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{sup 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{sup -}2) and the less acidic constant (0.13 kJ.mol{sup -}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) 30 refs.

Influence of milling process in the surface energy of glass tile frits; Influencia de la molienda en la energia superficial de fritas para esmaltes

Energy Technology Data Exchange (ETDEWEB)

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

2013-06-01

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{sub 2} by 5% of B{sub 2}O{sub 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{sup 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{sup -}2) and the less acidic constant (0.13 kJ.mol{sup -}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)

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.

Polycrystalline Nd{sub 2}Fe{sub 14}B/α-Fe nanocomposite flakes with a sub-micro/nanometre thickness prepared by surfactant-assisted high-energy ball milling

Energy Technology Data Exchange (ETDEWEB)

Tang, Xin, E-mail: tangshincn@gmail.com [Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Chen, Xi [Mechanical and Electrical Engineering College, Xinxiang University, No. 192, Jinsui Road, Xinxiang, Henan 453003 (China); Chen, Renjie; Yan, Aru [Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China)

2015-09-25

Highlights: • Nd{sub 2}Fe{sub 14}B/α-Fe flakes are formed by peeling along preferential planes. • (0 0 l) planes are found to be preferential cleavage planes. • Magnetic properties degrade with increasing ball milling time. • Anisotropic nanocomposite magnets are fabricated. - Abstract: A surfactant-assisted high-energy ball milling technique was employed to synthesize Nd{sub 2}Fe{sub 14}B/α-Fe nanoparticles and nanoflakes from melt-spun nanocrystalline powders. The microstructure evolution in ball milling process was investigated. In the beginning stage (0–4 h) of ball milling, raw powders were crushed into micrometre-sized particles. While flakes were mainly formed by reducing thickness of particles via peeling layer by layer along preferential planes in the late stage (8–16 h). The selected area electron diffraction and high-resolution transmission electron microscopy images show that preferential cleavage planes are basal planes. With ball milling proceeding, more and more defects were induced by ball milling. As a result, the coercivity and remanence decreased to 1.6 kOe and 3.2 kGs, respectively. After 16 h ball milling, the exchange decoupling occurred due to severe amorphorization. A weakly-textured nanocomposite magnet was fabricated after 12 h ball milling and the anisotropy in magnetic properties can be further improved by employing settling down process to select particle size and aligning particles in external field.

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.

Effect of milling time on the structure, particle size, and morphology of montmorillonite

International Nuclear Information System (INIS)

Abareshi, M.

2017-01-01

In the current research, effect of milling on the structure, particle size and morphology of montmorillonite was investigated. For this purpose, the montmorillonite was analyzed by X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. Then the montmorillonite was milled using high energy planetary ball mill at different milling times (1-60 hours). After that, the structure, particle size and morphology of all samples were investigated by XRD, FTIR, SEM, and transmission electron microscopy. Results showed that the ball milling causes the particle size reduction of clay and separation of the clay layers. Moreover, ball milling increases the overall structural disorder and transforms the crystalline structure into an amorphous phase. Also, the morphology of clay particle changes from layered to aggregates of almost rounded particles after 60 hours of milling.

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.

Reversible a-Fe2O3 to Fe3O4 transformation during ball milling

DEFF Research Database (Denmark)

Linderoth, Søren; Jiang, Jianzhong; Mørup, Steen

1997-01-01

The transformation of hematite to magnetite by high-energy ball milling in a sealed container has been studied by Mossbauer spectroscopy and x-ray diffraction. Mechanisms for this transformation are critically discussed. The dominant mechanism is concluded to be due to bond breaking during the high...... energy ball milling followed by release of the oxygen from the vial. The reverse transformation, magnetite to hematite, is demonstrated to occur by ball milling in air. Mechanisms for this reverse transformation are also put forward....

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.

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.

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.

Discrete element method based scale-up model for material synthesis using ball milling

Science.gov (United States)

Santhanam, Priya Radhi

Mechanical milling is a widely used technique for powder processing in various areas. In this work, a scale-up model for describing this ball milling process is developed. The thesis is a combination of experimental and modeling efforts. Initially, Discrete Element Model (DEM) is used to describe energy transfer from milling tools to the milled powder for shaker, planetary, and attritor mills. The rolling and static friction coefficients are determined experimentally. Computations predict a quasisteady rate of energy dissipation, E d, for each experimental configuration. It is proposed that the milling dose defined as a product of Ed and milling time, t, divided by the mass of milled powder, mp characterizes the milling progress independently of the milling device or milling conditions used. Once the milling dose is determined for one experimental configuration, it can be used to predict the milling time required to prepare the same material in any milling configuration, for which Ed is calculated. The concept is validated experimentally for DEM describing planetary and shaker mills. For attritor, the predicted Ed includes substantial contribution from milling tool interaction events with abnormally high forces (>103 N). The energy in such events is likely dissipated to heat or plastically deform milling tools rather than refine material. Indeed, DEM predictions for the attritor correlate with experiments when such events are ignored in the analysis. With an objective of obtaining real-time indicators of milling progress, power, torque, and rotation speed of the impeller of an attritor mill are measured during preparation of metal matrix composite powders in the subsequent portion of this thesis. Two material systems are selected and comparisons made between in-situ parameters and experimental milling progress indicators. It is established that real-time measurements can certainly be used to describe milling progress. However, they need to be interpreted carefully

75 FR 78235 - Dodge Mill Realty, LLC; Notice of Preliminary Permit Application Accepted for Filing and...

Science.gov (United States)

2010-12-15

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 13890-000] Dodge Mill Realty, LLC; Notice of Preliminary Permit Application Accepted for Filing and Soliciting Comments, Motions To Intervene, and Competing Applications December 8, 2010. On December 3, 2010, Dodge Mill Realty...

Morphology and magnetic properties of CeCo5 submicron flakes prepared by surfactant-assisted high-energy ball milling

Science.gov (United States)

Zhang, J. J.; Gao, H. M.; Yan, Y.; Bai, X.; Su, F.; Wang, W. Q.; Du, X. B.

2012-10-01

CeCo5 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 α-cyanoacrylate. Scanning electron microscope pictures show that the particles are flakes, several μm 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.

Energy dissipation in a finite volume of magnetic fluid

Energy Technology Data Exchange (ETDEWEB)

Bashtovoi, V.; Motsar, A.; Reks, A., E-mail: alexfx20@yandex.ru

2017-06-01

This study is devoted to investigation of energy dissipation processes which happen in a magnetic fluid drop with compound magnet during its motion in cylindrical non magnetic container. The possibility of energy dissipation control by means of electromagnetic field is examined. It's found that a change of magnetic field of compound magnet can lead to both increase and decrease of oscillation decay time and relative damping factor can be varied in a range of ±35%.

76 FR 9340 - Mill Town Power Project; Notice of Preliminary Permit Application Accepted for Filing and...

Science.gov (United States)

2011-02-17

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 13995-000] Mill Town Power Project; Notice of Preliminary Permit Application Accepted for Filing and Soliciting Comments, Motions To Intervene, and Competing Applications On January 4, 2011, Mill Town Power Project filed an application for a...

Asymptotic properties of spherically symmetric, regular and static solutions to Yang-Mills equations

International Nuclear Information System (INIS)

Cronstrom, C.

1987-01-01

In this paper the author discusses the asymptotic properties of solutions to Yang-Mills equations with the gauge group SU(2), for spherically symmetric, regular and static potentials. It is known, that the pure Yang-Mills equations cannot have nontrivial regular solutions which vanish rapidly at space infinity (socalled finite energy solutions). So, if regular solutions exist, they must have non-trivial asymptotic properties. However, if the asymptotic behaviour of the solutions is non-trivial, then the fact must be explicitly taken into account in constructing the proper action (and energy) for the theory. The elucidation of the appropriate surface correction to the Yang-Mills action (and hence the energy-momentum tensor density) is one of the main motivations behind the present study. In this paper the author restricts to the asymptotic behaviour of the static solutions. It is shown that this asymptotic behaviour is such that surface corrections (at space-infinity) are needed in order to obtain a well-defined (classical) theory. This is of relevance in formulating a quantum Yang-Mills theory

Effect of pressurization on helical guided wave energy velocity in fluid-filled pipes.

Science.gov (United States)

Dubuc, Brennan; Ebrahimkhanlou, Arvin; Salamone, Salvatore

2017-03-01

The effect of pressurization stresses on helical guided waves in a thin-walled fluid-filled pipe is studied by modeling leaky Lamb waves in a stressed plate bordered by fluid. Fluid pressurization produces hoop and longitudinal stresses in a thin-walled pipe, which corresponds to biaxial in-plane stress in a plate waveguide model. The effect of stress on guided wave propagation is accounted for through nonlinear elasticity and finite deformation theory. Emphasis is placed on the stress dependence of the energy velocity of the guided wave modes. For this purpose, an expression for the energy velocity of leaky Lamb waves in a stressed plate is derived. Theoretical results are presented for the mode, frequency, and directional dependent variations in energy velocity with respect to stress. An experimental setup is designed for measuring variations in helical wave energy velocity in a thin-walled water-filled steel pipe at different levels of pressure. Good agreement is achieved between the experimental variations in energy velocity for the helical guided waves and the theoretical leaky Lamb wave solutions. Copyright © 2016 Elsevier B.V. All rights reserved.

Fabrication and characterization of Cu/YSZ cermet high temperature electrolysis cathode material prepared by high-energy ball-milling method

International Nuclear Information System (INIS)

Lee, Sungkyu; Kim, Jong-Min; Hong, Hyun Seon; Woo, Sang-Kook

2009-01-01

Cu/YSZ cermet (40 and 60 vol.% Cu powder with balance YSZ) is a more economical cathode material than the conventional Ni/YSZ cermet for high temperature electrolysis (HTE) of water vapor and it was successfully fabricated by high-energy ball-milling of Cu and YSZ powders, pressing into pellets (o 13 mm x 2 mm) and subsequent sintering process at 700 deg. C under flowing 5%-H 2 /Ar gas. The Cu/YSZ composite material thus fabricated was characterized using various analytical tools such as XRD, SEM, and laser diffraction and scattering method. Electrical conductivity of sintered Cu/YSZ cermet pellets thus fabricated was measured by using 4-probe technique for comparison with that of conventional Ni/YSZ cermets. The effect of composite composition on the electrical conductivity was investigated and a marked increase in electrical conductivity for copper contents greater than 40 vol.% in the composite was explained by percolation threshold. Also, Cu/YSZ cermet was selected as a candidate for HTE cathode of self-supporting planar unit cell and its electrochemical performance was investigated, paving the way for preliminary correlation of high-energy ball-milling parameters with observed physical and electrochemical performance of Cu/YSZ cermets

Biomass by-product from crystal sugar production: A comparative study between Ngadirejo and Mauritius sugar mill

Science.gov (United States)

Gunawan; Bantacut, T.; Romli, M.; Noor, E.

2018-03-01

Sugarcane has been used as raw material in crystal sugar industry. Sugar cane that contains high sugar will be utilized into crystals sugar. In addition, the productivity of sugarcane is large enough in 2016 approximately 360 713 tons/year. Crystal sugar itself is a daily necessity for its use in the food and beverage industry. Problem that occurs in Indonesia is the energy consumption. The sugar mills supposed to be an independent energy source which means it can produce its own energy by utilization the material that is available in the sugar mills such as by-product (bagasse, molasses, filter cake, etc.), the by product in every production stage are quite a lot in sugar industry especially in Indonesia. In this paper, a comparison between two sugar mills was examined between Ngedirejo sugar mill and Mauritius sugar mill which has the same geological state as Indonesia. The results of comparison between the two sugar factories demonstrated the difference in terms of productivity of the sugar that has been produced and the effectiveness of the production process in a sugar mill seen from the amount of waste and the by product.

The energy supplied to a body in the theory of relativity and the impulse-energy tensor of a compressible fluid

International Nuclear Information System (INIS)

Ricard, J.

1979-01-01

In the relativity theory, the variation of a certain amount of energy supplied to a body, according to its speed, has been a matter of controversy. We study this variation either for a fluid that is submitted by a compression, or for a gas receiving heat from outward. It is shown that the problem is solved by a simple matter of definition of the energy received in the system of coordinate where the body is moving. Besides, we establish the impulse-energy tensor for a compressible fluid [fr

Aluminum-graphite composite produced by mechanical milling and hot extrusion

International Nuclear Information System (INIS)

Flores-Zamora, M.I.; Estrada-Guel, I.; Gonzalez-Hernandez, J.; Miki-Yoshida, M.; Martinez-Sanchez, R.

2007-01-01

Aluminum-graphite composites were produced by mechanical milling followed by hot extrusion. Graphite content was varied between 0 and 1 wt.%. Al-graphite mixtures were initially mixed in a shaker mill without ball, followed by mechanical milling in a High-energy simoloyer mill for 2 h under argon atmosphere. Milled powders were subsequently pressed at ∼950 MPa for 2 min, and next sintered under vacuum for 3 h at 823 K. Finally, sintered products were held for 0.5 h at 823 K and hot extruded using indirect extrusion. Tension and compression tests were carried out to determine the yield stress and maximum stress of the materials. We found that the mechanical resistance increased as the graphite content increased. Microstructural characterization was done by transmission electron microscopy. Al-O-C nanofibers and graphite nanoparticles were observed in extruded samples by transmission electron microscopy. These nanoparticles and nanofibers seemed to be responsible of the reinforcement phenomenon

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

Synthesis of ferrite nanoparticle by milling process for preparation of single domain magnet

International Nuclear Information System (INIS)

Suryadi; Hasbiyallah; Agus S W; Nurul TR; Budhy Kurniawan

2009-01-01

Study of ferrite nanoparticle synthesis for preparation of single domain magnet by milling of scrap magnet material have been done. Sample preparation were done using disk mill continued with high energy milling (HEM). Some powder were taken after 5, 10 dan 20 hours milling using HEM-E3D. The powder were then characterized using X-Ray Fluorescence (XRF), X-Ray Diffractometer (XRD) and Scanning Electron Microscope (SEM). XRF characterization result, confirmed by XRD analysis result, showed that the sample are of Strontium ferrite phase. Microstructure analysis result showed the occurrence of grain refining process of ferrite particle with increasing of milling time. Particle having size of nanometers successfully obtained, although in unhomogeneous distribution. Magnetic properties characterization result showed the increasing of hysteresis curve area of sample for longer milling time and sintering process. (author)

Study of the sintering behavior of fine, ultrafine and nanocrystalline WC-CO mixtures obtained by high energy milling

International Nuclear Information System (INIS)

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

2008-01-01

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

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.

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

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)

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

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

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...

SnSe/carbon nanocomposite synthesized by high energy ball milling as an anode material for sodium-ion and lithium-ion batteries

International Nuclear Information System (INIS)

Zhang, Zhian; Zhao, Xingxing; Li, Jie

2015-01-01

Graphical abstract: A homogeneous nanocomposite of SnSe and carbon black was synthesised by high energy ball milling and empolyed as an anode material for sodium-ion batteries (SIBs) and lithium-ion batteries (LIBs). The nanocomposite anode exhibits excellent electrochemical performances in both SIBs and LIBs. - Highlights: • A homogeneous nanocomposite of SnSe and carbon black was fabricated by high energy ball milling. • SnSe and carbon black are homogeneously mixed at the nanoscale level. • The SnSe/C anode exhibits excellent electrochemical performances in both SIBs and LIBs. - Abstract: A homogeneous nanocomposite of SnSe and carbon black, denoted as SnSe/C nanocomposite, was fabricated by high energy ball milling and empolyed as a high performance anode material for both sodium-ion batteries and lithium-ion batteries. The X-ray diffraction patterns, scanning electron microscopy and transmission electron microscopy observations confirmed that SnSe in SnSe/C nanocomposite was homogeneously distributed within carbon black. The nanocomposite anode exhibited enhanced electrochemical performances including a high capacity, long cycling behavior and good rate performance in both sodium-ion batteries (SIBs) and lithium-ion batteries (LIBs). In SIBs, an initial capacitiy of 748.5 mAh g −1 was obtained and was maintained well on cycling (324.9 mAh g −1 at a high current density of 500 mA g −1 in the 200 th cycle) with 72.5% retention of second cycle capacity (447.7 mAh g −1 ). In LIBs, high initial capacities of approximately 1097.6 mAh g −1 was obtained, and this reduced to 633.1 mAh g −1 after 100 cycles at 500 mA g −1

78 FR 34091 - Wausau Paper Mills, LLC; Specialty Papers Acquisition, LLC; Notice of Application for Transfer of...

Science.gov (United States)

2013-06-06

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project Nos. 2161-034; 2207-045] Wausau Paper Mills, LLC; Specialty Papers Acquisition, LLC; Notice of Application for Transfer of Licenses, and Soliciting Comments and Motions To Intervene On April 22, 2013, Wausau Paper Mills, LLC (transferor) and...

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.

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)

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)

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.

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

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

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

Residual stresses analysis in ball end milling of nickel-based superalloy Inconel 718

Energy Technology Data Exchange (ETDEWEB)

Wang, Junteng; Zhang, Dinghua; Wu, Baohai; Luo, Ming [Key Laboratory of Contemporary Design and Integrated Manufacturing Technology, Northwestern Polytechnical University (China)

2017-11-15

Inconel 718 is widely used in the aviation, space, automotive and biomedical industries because of its outstanding properties. Near-surface residual stresses that are induced by ball end milling in Inconel 718 can be crucial for the performance and service time of the machined parts. In this paper, the influences of cutting conditions, including the use of cutting parameters, cutting fluid and spindle angles, on the residual stresses in the ball end milling process of Inconel 718 alloy were investigated experimentally. X-ray diffraction measurements reveal that residual stress distributions are highly influenced by cutting parameters, especially the depth of cut and cutting speed. The milling operation with cooling induces more compressive stresses trend and the magnitude of the residual stresses increases in the tensile direction with the increase of spindle angles. These cutting induced effects were further discussed with respect to thermal- mechanical coupling theory and some observations made by optical microscopy. From this investigation, it is suggested that the machining process parameters are not the smaller the better for the control of residual stresses in the ball end milling process of Inconel 718. (author)

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...... by micro milling. Examples of test parts are shown and used as an experimental validation....

Uranium Mill Tailings Management

International Nuclear Information System (INIS)

Nelson, J.D.

1982-01-01

This book presents the papers given at the Fifth Symposium on Uranium Mill Tailings Management. Advances made with regard to uranium mill tailings management, environmental effects, regulations, and reclamation are reviewed. Topics considered include tailings management and design (e.g., the Uranium Mill Tailings Remedial Action Project, environmental standards for uranium mill tailings disposal), surface stabilization (e.g., the long-term stability of tailings, long-term rock durability), radiological aspects (e.g. the radioactive composition of airborne particulates), contaminant migration (e.g., chemical transport beneath a uranium mill tailings pile, the interaction of acidic leachate with soils), radon control and covers (e.g., radon emanation characteristics, designing surface covers for inactive uranium mill tailings), and seepage and liners (e.g., hydrologic observations, liner requirements)

Preliminary Test of Upgraded Conventional Milling Machine into PC Based CNC Milling Machine

International Nuclear Information System (INIS)

Abdul Hafid

2008-01-01

CNC (Computerized Numerical Control) milling machine yields a challenge to make an innovation in the field of machining. With an action job is machining quality equivalent to CNC milling machine, the conventional milling machine ability was improved to be based on PC CNC milling machine. Mechanically and instrumentally change. As a control replacing was conducted by servo drive and proximity were used. Computer programme was constructed to give instruction into milling machine. The program structure of consists GUI model and ladder diagram. Program was put on programming systems called RTX software. The result of up-grade is computer programming and CNC instruction job. The result was beginning step and it will be continued in next time. With upgrading ability milling machine becomes user can be done safe and optimal from accident risk. By improving performance of milling machine, the user will be more working optimal and safely against accident risk. (author)

Heterogeneous sono-Fenton-like process using martite nanocatalyst prepared by high energy planetary ball milling for treatment of a textile dye.

Science.gov (United States)

Dindarsafa, Mahsa; Khataee, Alireza; Kaymak, Baris; Vahid, Behrouz; Karimi, Atefeh; Rahmani, Amir

2017-01-01

High energy planetary ball milling was applied to prepare sono-Fenton nanocatalyst from natural martite (NM). The NM samples were milled for 2-6h at the speed of 320rpm for production of various ball milled martite (BMM) samples. The catalytic performance of the BMMs was greater than the NM for treatment of Acid Blue 92 (AB92) in heterogeneous sono-Fenton-like process. The NM and the BMM samples were characterized by XRD, FT-IR, SEM, EDX and BET analyses. The particle size distribution of the 6h-milled martite (BMM 3 ) was in the range of 10-90nm, which had the highest surface area compared to the other samples. Then, the impact of main operational parameters was investigated on the process. Complete removal of the dye was obtained at the desired conditions including initial pH 7, 2.5g/L BMM 3 dosage, 10mg/L AB92 concentration, and 150W ultrasonic power after 30min of treatment. The treatment process followed pseudo-first order kinetic. Environmentally-friendly modification of the NM, low leached iron amount and repeated application at milder pH were the significant benefits of the BMM 3 . The GC-MS was successfully used to identify the generated intermediates. Eventually, an artificial neural network (ANN) was applied to predict the AB92 removal efficiency based upon the experimental data with a proper correlation coefficient (R 2 =0.9836). Copyright © 2016 Elsevier B.V. All rights reserved.

Loop groups and Yang-Mills theory in dimension two

DEFF Research Database (Denmark)

Gravesen, Jens

1990-01-01

Given a connection ω in a G-bundle over S2, then a process called radial trivialization from the poles gives a unique clutching function, i.e., an element γ of the loop group ΩG. Up to gauge equivalence, ω is completely determined by γ and a map f:S2 →g into the Lie algebra. Moreover, the Yang......-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...

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

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.

A novel fabrication technology of in situ TiB{sub 2}/6063Al composites: High energy ball milling and melt in situ reaction

Energy Technology Data Exchange (ETDEWEB)

Zhang, S.-L.; Yang, J. [School of Materials Science and Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013 (China); Zhang, B.-R. [School of Mechanical Engineering, Qilu University of Technology, Jinan, Shandong 250022 (China); Zhao, Y.-T., E-mail: 278075525@qq.com [School of Materials Science and Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013 (China); Chen, G.; Shi, X.-X.; Liang, Z.-P. [School of Materials Science and Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013 (China)

2015-08-05

Highlights: • This paper presents a novel technology to fabricate the TiB{sub 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{sub 2}/6063Al matrix composites are fabricated from Al–TiO{sub 2}–B{sub 2}O{sub 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{sub 2}–B{sub 2}O{sub 3} system in contrast with the conventional melt in situ synthesis. The morphology of in situ TiB{sub 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{sub 2} particles is clear and no interfacial outgrowth is observed. Tensile testing results show that the as-cast TiB{sub 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.

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...

Effects of Dry-Milling and Wet-Milling on Chemical, Physical and Gelatinization Properties of Rice Flour

Directory of Open Access Journals (Sweden)

Jitranut Leewatchararongjaroen

2016-09-01

Full Text Available Rice flour from nine varieties, subjected to dry- and wet-milling processes, was determined for its physical and chemical properties. The results revealed that milling method had an effect on properties of flour. Wet-milling process resulted in flour with significantly lower protein and ash contents and higher carbohydrate content. Wet-milled flour also tended to have lower lipid content and higher amylose content. In addition, wet-milled rice flour contained granules with smaller average size compared to dry-milled samples. Swelling power at 90 °C of wet-milled samples was higher while solubility was significantly lower than those of dry-milled flour. Dry milling process caused the destruction of the crystalline structure and yielded flour with lower crystallinity compared to wet-milling process, which resulted in significantly lower gelatinization enthalpy.

Binary Mixture of Perfect Fluid and Dark Energy in Modified Theory of Gravity

Science.gov (United States)

Shaikh, A. Y.

2016-07-01

A self consistent system of Plane Symmetric gravitational field and a binary mixture of perfect fluid and dark energy in a modified theory of gravity are considered. The gravitational field plays crucial role in the formation of soliton-like solutions, i.e., solutions with limited total energy, spin, and charge. The perfect fluid is taken to be the one obeying the usual equation of state, i.e., p = γρ with γ∈ [0, 1] whereas, the dark energy is considered to be either the quintessence like equation of state or Chaplygin gas. The exact solutions to the corresponding field equations are obtained for power-law and exponential volumetric expansion. The geometrical and physical parameters for both the models are studied.

Correlation of gas sensitivite properties with microstructure of Fe2O3-SnO2 ceramics prepared by high energy ball milling

DEFF Research Database (Denmark)

Jiang, Jianzhong; Lu, S.W.; Zhou, Y.X.

1997-01-01

A remarkable gas sensitivity to ethnaol gas has been observed in nanostructured Fe2O3-SnO2 materials with a composition of 6.4 mol% SnO2 prepared by high energy ball milling. The microstructure of the materials has been examined by x-ray diffraction (XRD) and Mossbauer spectroscopy. It was found...

Investigation of the milling capabilities of the F10 Fine Grind mill using Box-Behnken designs.

Science.gov (United States)

Tan, Bernice Mei Jin; Tay, Justin Yong Soon; Wong, Poh Mun; Chan, Lai Wah; Heng, Paul Wan Sia

2015-01-01

Size reduction or milling of the active is often the first processing step in the design of a dosage form. The ability of a mill to convert coarse crystals into the target size and size distribution efficiently is highly desirable as the quality of the final pharmaceutical product after processing is often still dependent on the dimensional attributes of its component constituents. The F10 Fine Grind mill is a mechanical impact mill designed to produce unimodal mid-size particles by utilizing a single-pass two-stage size reduction process for fine grinding of raw materials needed in secondary processing. Box-Behnken designs were used to investigate the effects of various mill variables (impeller, blower and feeder speeds and screen aperture size) on the milling of coarse crystals. Response variables included the particle size parameters (D10, D50 and D90), span and milling rate. Milled particles in the size range of 5-200 μm, with D50 ranging from 15 to 60 μm, were produced. The impeller and feeder speeds were the most critical factors influencing the particle size and milling rate, respectively. Size distributions of milled particles were better described by their goodness-of-fit to a log-normal distribution (i.e. unimodality) rather than span. Milled particles with symmetrical unimodal distributions were obtained when the screen aperture size was close to the median diameter of coarse particles employed. The capacity for high throughput milling of particles to a mid-size range, which is intermediate between conventional mechanical impact mills and air jet mills, was demonstrated in the F10 mill. Prediction models from the Box-Behnken designs will aid in providing a better guide to the milling process and milled product characteristics. Copyright © 2014 Elsevier B.V. All rights reserved.

Estimation of Moisture Content in Coal in Coal Mills

DEFF Research Database (Denmark)

Odgaard, Peter Fogh; Mataji, B.

the moisture content of the coal is proposed based on a simple dynamic energy model of a coal mill, which pulverizes and dries the coal before it is burned in the boiler. An optimal unknown input observer is designed to estimate the moisture content based on an energy balance model. The designed moisture...

Estimation of Moisture Content in Coal in Coal Mills

DEFF Research Database (Denmark)

Odgaard, Peter Fogh; Mataji, Babak

2006-01-01

the moisture content of the coal is proposed based on a simple dynamic energy model of a coal mill, which pulverizes and dries the coal before it is burned in the boiler. An optimal unknown input observer is designed to estimate the moisture content based on an energy balance model. The designed moisture...

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

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

International Nuclear Information System (INIS)

Carreño-Gallardo, C.; Estrada-Guel, I.; López-Meléndez, C.; Martínez-Sánchez, R.

2014-01-01

Highlights: • Synthesis of 2024-SiC 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 2024 alloy was reinforced with silicon carbide nanoparticles (SiC 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 NP were homogeneously dispersed into the Al 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 NP content. In this research several strengthening mechanisms were observed, but the main was the obstruction of dislocations movement by the addition of SiC NP

Predicting radon flux from uranium mill tailings

International Nuclear Information System (INIS)

Freeman, H.D.; Hartley, J.N.

1983-11-01

Pacific Northwest Laboratory (PNL), under contract to the US Department of Energy (DOE) Uranium Mill Tailings Remedial Action Project (UMTRAP) office, is developing technology for the design of radon barriers for uranium mill tailings piles. To properly design a radon cover for a particular tailings pile, the radon flux emanating from the bare tailings must be known. The tailings characteristics required to calculate the radon flux include radium-226 content, emanating power, bulk density, and radon diffusivity. This paper presents theoretical and practical aspects of estimating the radon flux from an uranium tailings pile. Results of field measurements to verify the calculation methodology are also discussed. 24 references, 4 figures, 4 tables

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.

Relativistic Fluid Dynamics Far From Local Equilibrium

Science.gov (United States)

Romatschke, Paul

2018-01-01

Fluid dynamics is traditionally thought to apply only to systems near local equilibrium. In this case, the effective theory of fluid dynamics can be constructed as a gradient series. Recent applications of resurgence suggest that this gradient series diverges, but can be Borel resummed, giving rise to a hydrodynamic attractor solution which is well defined even for large gradients. Arbitrary initial data quickly approaches this attractor via nonhydrodynamic mode decay. This suggests the existence of a new theory of far-from-equilibrium fluid dynamics. In this Letter, the framework of fluid dynamics far from local equilibrium for a conformal system is introduced, and the hydrodynamic attractor solutions for resummed Baier-Romatschke-Son-Starinets-Stephanov theory, kinetic theory in the relaxation time approximation, and strongly coupled N =4 super Yang-Mills theory are identified for a system undergoing Bjorken flow.

Direct heat transfer considerations for improving energy efficiency in pulp and paper Kraft mills

International Nuclear Information System (INIS)

Savulescu, Luciana Elena; Alva-Argaez, Alberto

2008-01-01

The success of any process improvement study depends on the quality of the available data and the way in which the plant-specific characteristics are incorporated in the applied conceptual models; in the context of process integration studies these issues are directly related to the rules followed during the data extraction stage. Improving energy efficiency in a pulp and paper Kraft mill requires the identification of the most promising heat recovery network retrofit projects. In a retrofit analysis using pinch technology/process integration methods, only the process streams associated to the existing heat exchangers and some outlet streams (such as wastewater/effluent streams and vents) with high potential for heat recovery are usually included, while the energy exchanged through non-isothermal stream mixing (NIM) or direct heat transfer (DHT) is often assumed fixed and is not considered in the analysis. Relaxing this assumption requires extracting more data to represent the DHT design configuration that exists in the plant. However, different data extraction options can be considered to represent the DHT configuration depending on the associated process/operation constraints. This work describes a systematic procedure to extract and analyse the impacts of DHT on the overall energy efficiency of a Kraft process with a specific focus on mixing along the pulp line and in water tanks

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...

75 FR 71463 - Woodland Mills Corporation Mill Spring, NC; Notice of Revised Determination on Reconsideration

Science.gov (United States)

2010-11-23

... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-73,695] Woodland Mills Corporation Mill Spring, NC; Notice of Revised Determination on Reconsideration By application dated July 22... regarding the eligibility of workers and former workers of Woodland Mills Corporation, Mill Spring, North...

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

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...

Non-Abelian S-term dark energy and inflation

Science.gov (United States)

Rodríguez, Yeinzon; Navarro, Andrés A.

2018-03-01

We study the role that a cosmic triad in the generalized SU(2) Proca theory, specifically in one of the pieces of the Lagrangian that involves the symmetric version Sμν of the gauge field strength tensor Fμν, has on dark energy and primordial inflation. Regarding dark energy, the triad behaves asymptotically as a couple of radiation perfect fluids whose energy densities are negative for the S term but positive for the Yang-Mills term. This leads to an interesting dynamical fine-tuning mechanism that gives rise to a combined equation of state parameter ω ≃ - 1 and, therefore, to an eternal period of accelerated isotropic expansion for an ample spectrum of initial conditions. Regarding primordial inflation, one of the critical points of the associated dynamical system can describe a prolonged period of isotropic slow-roll inflation sustained by the S term. This period ends up when the Yang-Mills term dominates the energy density leading to the radiation dominated epoch. Unfortunately, in contrast to the dark energy case, the primordial inflation scenario is strongly sensitive to the coupling constants and initial conditions. The whole model, including the other pieces of the Lagrangian that involve Sμν, might evade the recent strong constraints coming from the gravitational wave signal GW170817 and its electromagnetic counterpart GRB 170817A.

Investigations on Surface Milling of Hardened AISI 4140 Steel with Pulse Jet MQL Applicator

Science.gov (United States)

Bashir, Mahmood Al; Mia, Mozammel; Dhar, Nikhil Ranjan

2018-06-01

In this article, an experimental investigation was performed in milling hardened AISI 4140 steel of hardness 40 HRC. The machining was performed in both dry and minimal quantity lubricant (MQL) conditions, as part of neat machining, to make a strong comparison of the undertaken machining environments. The MQL was impinged int the form of pulse jet, by using the specially developed pulse-jet-attachment, to ensure that the cutting fluid can be applied in different timed pulses and quantities at critical zones. The tool wear, cutting force and surface roughness were taken as the quality responses while cutting speed, table feed rate and flow rate of the pulse were considered as influential factors. The depth of cut was kept constant at 1.50 mm because of its less significant effects and the straight oil was adopted as cutting fluid in pulse-jet-MQL. The effects of different factors, on the quality responses, are analyzed using ANOVA. It is observed that MQL applicator system exhibits overall better performance when compared to dry milling by reducing surface roughness, cutting force and prolonging tool life but a flow rate of 150 ml/h has tremendous effects on the responses. This investigation and afterward results are expected to aid the industrial practitioner and researcher to adopt the pulse-MQL in high speed milling to prolong tool life, reduce tool wear, diminish cutting force generation and promote better surface finish.

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

Influence of the milling time in the microstructural parameters of TA2O5-Al powder refined by Rietveld method

International Nuclear Information System (INIS)

Brito, R.A.; Mendes, M.W.D.; Alves Junior, C.; Costa, F.A. da; Gomes, U.U.

2009-01-01

Mechanical alloying (MA) is a solid-state powder processing technique involving repeated welding, fracturing, and re-welding of powder particles in a high energy mill. This process is used for producing of fine powders containing unique microstructures. The process starts with mixing of the powders in the desired proportion. Then, the mixture is milled using the established time in the high-energy mill. The powder particles are submitted to repeated cycles of cold working and fracture, and the final product correspond to a composite powder, containing characteristics different of the initial constituents. Ta 2 O 5 -Al powders were milled in a planetary ball mill for different times in order to evaluate the influence of the milling time in their microstructural parameters like crystallite size and micro deformation. The microstructural parameters were obtained by the Rietveld Method. The results showed that the microstructural parameters were influenced by the increase of the milling time. (author)

Biotechnological applications for the utilisation of wastes from palm oil mills

Energy Technology Data Exchange (ETDEWEB)

Cheah, S C; Ma, A N; Ooi, L C.L.; Ong, A S.H.

1988-05-01

The milling of oil palm fruits produces about two-and-a-half to three times as much effluent as oil does. It also generates a large amount of lignocellulosic wastes, mainly in the form of empty fruit bunches, press cake fibres and nut shell. Research efforts at PORIM have been directed towards the utilisation of these wastes as a means to solve the problem of environmental pollution as well as for the generation of economic returns for the mills. We have studied a thermophilic contact process for the anaerobic digestion of palm oil mill effluent and its potential for generating biogas for energy uses. Our work has also shown that the condensate derived from the fruit sterilisation process during milling is amenable to fermentation for the production of single cell protein (SCP) and exo-enzymes. The enzymes produced have been applied for oil clarification, oil recovery from press cake fibers and saccharification of the fibers for the production of sugar feedstocks. This paper will also introduce the concept of integrated waste management for the palm oil mill through the implementation of these technologies.

Evaluation of End Mill Coatings

Energy Technology Data Exchange (ETDEWEB)

L. J. Lazarus; R. L. Hester,

2005-08-01

Milling tests were run on families of High Speed Steel (HSS) end mills to determine their lives while machining 304 Stainless Steel. The end mills tested were made from M7, M42 and T15-CPM High Speed Steels. The end mills were also evaluated with no coatings as well as with Titanium Nitride (TiN) and Titanium Carbo-Nitride (TiCN) coatings to determine which combination of HSS and coating provided the highest increase in end mill life while increasing the cost of the tool the least. We found end mill made from M42 gave us the largest increase in tool life with the least increase in cost. The results of this study will be used by Cutting Tool Engineering in determining which end mill descriptions will be dropped from our tool catalog.

Microstructural analysis of sinterized aluminum powder obtained by the high energy milling of beverage cans; Analise microestrutural de po de aluminio sinterizado obtido pela moagem de alta energia de latas de bebidas

Energy Technology Data Exchange (ETDEWEB)

Souza, Jose Raelson Pereira de; Peres, Mauricio Mhirdaui, E-mail: mauricioperes@ct.ufrn.br [Universidade Federal do Rio Grande do Norte (UFRN), RN (Brazil)

2016-07-01

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.

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

Science.gov (United States)

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.

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

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.

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.

A Note on Supergravity Duals of Noncommutative Yang-Mills Theory

International Nuclear Information System (INIS)

Das, Sumit R.; Ghosh, Banhiman

2000-01-01

A class of supergravity backgrounds have been proposed as dual descriptions of strong coupling large-N noncommutative Yang-Mills (NCYM) theories in 3+1 dimensions. However calculations of correlation functions in supergravity from an evaluation of relevant classical actions appear ambiguous. We propose a resolution of this ambiguity. Assuming that holographic description exists - regardless of whether it is the NCYM theory - we argue that there should be operators in the holographic boundary theory which create normalized states of definite energy and momenta. An operator version of the dual correspondence then provides a calculation of correlators of these operators in terms of bulk Green's functions. We show that in the low energy limit the correlators reproduce expected answers of the ordinary Yang-Mills theory. (author)

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...

Non self-dual Yang-Mills fields

International Nuclear Information System (INIS)

Bor, G.

1991-01-01

The purpose of the thesis is to prove the existence of a new family of non self-dual finite-energy solutions to the Yang-Mills equations on Euclidean four-space, with SU(2) as a gauge group. The approach is that of equivalent geometry: attention is restricted to a special class of fields, those that satisfy a certain kind of rotational symmetry which it is proved that (1) a solution to the Yang-Mills equations exists for among them, and (2) no solution to the self-duality equations exists among them. The first assertion is proved by an application of the direct method of the calculus of variations (existence and regularity of minimizers), and the second assertion by showing that the self-duality equations, linearized at a symmetric self-dual solution, cannot possess the required symmetry

Gravity flow operated small electricity generator retrofit kit to flour mill industry.

Science.gov (United States)

Shekara, Prithivi; Kumar V, Pavan; Hosamane, Gangadharappa Gundabhakthara

2013-10-01

Flour milling is a grinding process to produce flour from wheat through comprehensive stages of grinding and separation. The primary energy is required to provide power used in grinding of wheat. In wheat milling, tempering is the process of adding water to wheat before milling to toughen the bran and mellow the endosperm. Gravity flow of the wheat is utilized to rotate the dampener wheel with cups to add water. Low cost gravity flow operated small electricity generator retrofit kit for dampener was designed and developed to justify low cost energy production without expensive solutions. Results of statistical analysis indicated that there was significant difference in mean values for voltage, rpm and flow rate at the 95% probability level. The resulted maximum mechanical power and measured electrical power were 5.1 W and 4.9 W respectively at wheat flow rate of 1.6 Kg/s and dampener wheel rotational velocity of 4.4 rad/s.

The paradox of uranium development: A Polanyian analysis of social movements surrounding the Pinon Ridge Uranium Mill

Science.gov (United States)

Malin, Stephanie A.

Renewal of nuclear energy development has been proposed as one viable solution for reducing greenhouse gas emissions and impacts of climate change. This discussion became concrete as the first uranium mill proposed since the end of the Cold War, the Pinon Ridge Uranium Mill, received state permits in January 2011 to process uranium in southwest Colorado's Paradox Valley. Though environmental contamination from previous uranium activity caused one local community to be bulldozed to the ground, local support for renewed uranium activity emerges among local residents in communities like Nucla, Naturita, and Bedrock, Colorado. Regionally, however, a coalition of organized, oppositionbased grassroots groups fights the decision to permit the mill. Combined, these events allow social scientists a natural laboratory through which to view social repercussions of nuclear energy development. In this dissertation, I use a Polanyian theoretical framework to analyze social, political-economic, and environmental contexts of social movements surrounding PR Mill. My overarching research problem is: How might Polanyian double movement theory be applied to and made empirically testable within the social and environmental context of uranium development? I intended this analysis to inform energy policy debates regarding renewable energy. In Chapter 1, I found various forms of social dislocation lead to two divergent social movement outcomes. Economic social dislocation led to strong mill support among most local residents, according to archival, in-depth interview, and survey data. On the other hand, residents in regional communities experienced two other types of social dislocation -- another kind of economic dislocation, related to concern over boom-bust economies, and environmental health dislocations related to uranium exposure, creating conditions for a regional movement in opposition to PR Mill. In Chapter 2, I focus on regulations and find that two divergent social movements

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

Uranium Mill Tailings Remedial Action Project, Surface Project Management Plan. Revision 1

Energy Technology Data Exchange (ETDEWEB)

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.

Micro structrual characterization and analysis of ball milled silicon carbide

Science.gov (United States)

Madhusudan, B. M.; Raju, H. P.; Ghanaraja., S.

2018-04-01

Mechanical alloying has been one of the prominent methods of powder synthesis technique in solid state involving cyclic deformation, cold welding and fracturing of powder particles. Powder particles in this method are subjected to greater mechanical deformation due to the impact of ball-powder-ball and ball-powder-container collisions that occurs during mechanical alloying. Strain hardening and fracture of particles decreases the size of the particles and creates new surfaces. The objective of this Present work is to use ball milling of SiC powder for different duration of 5, 10, 15 and 20 hours by High energy planetary ball milling machine and to evaluate the effect of ball milling on SiC powder. Micro structural Studies using Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD) and EDAX has been investigated.

Experimental investigations on cryogenic cooling by liquid nitrogen in the end milling of hardened steel

Science.gov (United States)

Ravi, S.; Pradeep Kumar, M.

2011-09-01

Milling of hardened steel generates excessive heat during the chip formation process, which increases the temperature of cutting tool and accelerates tool wear. Application of conventional cutting fluid in milling process may not effectively control the heat generation also it has inherent health and environmental problems. To minimize health hazard and environmental problems caused by using conventional cutting fluid, a cryogenic cooling set up is developed to cool tool-chip interface using liquid nitrogen (LN 2). This paper presents results on the effect of LN 2 as a coolant on machinability of hardened AISI H13 tool steel for varying cutting speed in the range of 75-125 m/min during end milling with PVD TiAlN coated carbide inserts at a constant feed rate. The results show that machining with LN 2 lowers cutting temperature, tool flank wear, surface roughness and cutting forces as compared with dry and wet machining. With LN 2 cooling, it has been found that the cutting temperature was reduced by 57-60% and 37-42%; the tool flank wear was reduced by 29-34% and 10-12%; the surface roughness was decreased by 33-40% and 25-29% compared to dry and wet machining. The cutting forces also decreased moderately compared to dry and wet machining. This can be attributed to the fact that LN 2 machining provides better cooling and lubrication through substantial reduction in the cutting zone temperature.

Environmental control technology for mining, milling, and refining thorium

International Nuclear Information System (INIS)

Weakley, S.A.; Blahnik, D.E.; Young, J.K.; Bloomster, C.H.

1980-02-01

The purpose of this report is to evaluate, in terms of cost and effectiveness, the various environmental control technologies that would be used to control the radioactive wastes generated in the mining, milling, and refining of thorium from domestic resources. The technologies, in order to be considered for study, had to reduce the radioactivity in the waste streams to meet Atomic Energy Commission (10 CFR 20) standards for natural thorium's maximum permissible concentration (MPC) in air and water. Further regulatory standards or licensing requirements, either federal, state, or local, were not examined. The availability and cost of producing thorium from domestic resources is addressed in a companion volume. The objectives of this study were: (1) to identify the major waste streams generated during the mining, milling, and refining of reactor-grade thorium oxide from domestic resources; and (2) to determine the cost and levels of control of existing and advanced environmental control technologies for these waste streams. Six potential domestic deposits of thorium oxide, in addition to stockpiled thorium sludges, are discussed in this report. A summary of the location and characteristics of the potential domestic thorium resources and the mining, milling, and refining processes that will be needed to produce reactor-grade thorium oxide is presented in Section 2. The wastes from existing and potential domestic thorium oxide mines, mills, and refineries are identified in Section 3. Section 3 also presents the state-of-the-art technology and the costs associated with controlling the wastes from the mines, mills, and refineries. In Section 4, the available environmental control technologies for mines, mills, and refineries are assessed. Section 5 presents the cost and effectiveness estimates for the various environmental control technologies applicable to the mine, mill, and refinery for each domestic resource

78 FR 44107 - Monadnock Paper Mills, Inc.; Notice of Availability of Environmental Assessment

Science.gov (United States)

2013-07-23

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [ Project No. 6597-013-NH] Monadnock Paper Mills, Inc.; Notice of Availability of Environmental Assessment In accordance with the National Environmental Policy Act of 1969 and the Federal Energy Regulatory Commission's (Commission) regulations, 18 CFR...

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

Influence of temperature on hydrogen production from bread mill wastewater by sewage sludge

Energy Technology Data Exchange (ETDEWEB)

Tang, G.L.; Huang, J.; Li, Y.Y.; Sun, Z.J. [China Agricultural Univ., Beijing (China). College of Resources and Environmental Sciences; Tang, Q.Q. [Nanjing Univ., Nanjing (China). Medical School

2008-07-01

Hydrogen (H{sub 2}) energy has been touted as a sustainable and clean energy source that can solve environmental problems such as acid rain, greenhouse gases and transboundary pollution. While most hydrogen is currently produced from nonrenewable sources such as oil, natural gas, and coal, these processes are energy-intensive and costly. The biological production of hydrogen using fermentative bacteria is an environmentally friendly and energy-saving process which has recently attracted much attention as an effective way of converting biomass into H{sub 2}. Waste-based H{sub 2} production processes mainly include wastewater from paper mills, municipal solid waste, rice winery wastewater, and food wastewater from cafeterias. This study investigated the use of bread mill wastewater for biological production of hydrogen due to its high production potential. Annual bread production in China is estimated to be over 1.5 million tons, producing 10 m{sup 3} of wastewater per ton of bread. The wastewater has high chemical oxygen demand and carbohydrate concentrations and is therefore suitable for anaerobic treatment processes. This study evaluated the effect of temperature on H{sub 2} production from bread mill wastewater by sewage sludge in lab-scale experiments. H{sub 2} production, the distribution of volatile fatty acids and the lag-phase time were influenced by temperature. H{sub 2} production and H{sub 2} yield increased with increasing temperature. The optimal temperature for H{sub 2} production was 50 degrees C. Butyrate, acetate and alcohol were the main by-products of H{sub 2} fermentation. According to 16S rDNA analysis, the dominant microflora was Clostridium, but the microbial species varied with temperature. The activation energy for H{sub 2} production was estimated to be 92 kJ per mol for bread mill wastewater. It was concluded that bread mill wastewater could potentially serve as a substrate for H{sub 2} production. This research provides a means of

Quenching ilmenite with a high-temperature and high-pressure phase using super-high-energy ball milling.

Science.gov (United States)

Hashishin, Takeshi; Tan, Zhenquan; Yamamoto, Kazuhiro; Qiu, Nan; Kim, Jungeum; Numako, Chiya; Naka, Takashi; Valmalette, Jean Christophe; Ohara, Satoshi

2014-04-25

The mass production of highly dense oxides with high-temperature and high-pressure phases allows us to discover functional properties that have never been developed. To date, the quenching of highly dense materials at the gramme-level at ambient atmosphere has never been achieved. Here, we provide evidence of the formation of orthorhombic Fe2TiO4 from trigonal FeTiO3 as a result of the high-temperature (>1250 K) and high-pressure (>23 GPa) condition induced by the high collision energy of 150 gravity generated between steel balls. Ilmenite was steeply quenched by the surrounding atmosphere, when iron-rich ilmenite (Fe2TiO4) with a high-temperature and high-pressure phase was formed by planetary collisions and was released from the collision points between the balls. Our finding allows us to infer that such intense planetary collisions induced by high-energy ball milling contribute to the mass production of a high-temperature and high-pressure phase.

Research on the characterization and conditioning of uranium mill tailings. III. Summary of uranium mill tailings conditioning research and implications regarding remedial actions

International Nuclear Information System (INIS)

Dreesen, D.R.; Cokal, E.J.; Thode, E.F.; Williams, J.M.

1983-06-01

This report summarizes the findings of research on uranium mill tailings conditioning technology development performed for the Department of Energy's (DOE) Uranium Mill Tailings Remedial Action Project (UMTRAP). Hazards and risks posed by tailings piles are discussed in relation to the goal of conditioning the tailings to reduce these hazards. The results of our efforts regarding characterization of tailings, removal of radionuclides, mineral recovery, thermal stabilization, and engineering/economic analysis of conditioning are presented. The implications of these results for remedial action plans are discussed and conclusions regarding the applicability of these technologies are also presented

Determination of rational parameters for process of grinding materials pre-crushed by pressure in ball mill

Science.gov (United States)

Romanovich, A. A.; Romanovich, L. G.; Chekhovskoy, E. I.

2018-03-01

The article presents the results of experimental studies on the grinding process of a clinker preliminarily ground in press roller mills in a ball mill equipped with energy exchange devices. The authors studied the influence of the coefficients of loading for grinding bodies of the first and second mill chambers, their lengths, angles of inclination, and the mutual location of energy exchange devices (the ellipse segment and the double-acting blade) on the output parameters of the grinding process (productivity, drive power consumption and specific energy consumption). It is clarified that the best results of the disaggregation and grinding process, judging by the minimum specific energy consumption in the grinding of clinker with an anisotropic texture after force deformation between the rolls of a press roller shredder, are achieved at a certain angle of ellipse segment inclination; the length of the first chamber and the coefficients of loading the chambers with grinding bodies.

TECHNICAL NOTE: The effect of the green additive guar gum on the properties of magnetorheological fluid

Science.gov (United States)

Fang, Chen; Zhao, Bin Yuan; Chen, LeSheng; Wu, Qing; Liu, Nan; Hu, Ke Ao

2005-02-01

Magnetorheological (MR) fluid containing guar gum was prepared for the first time by ball-milling the guar gum powder together with silicone oil and carbonyl iron powder. By forming a coating layer over the ground carbonyl iron powder, the guar gum improves the sedimentation stability and thixotropy of the MR fluid effectively.

Study of the behaviour of the yellow cake dissolution in simulated lung fluid

International Nuclear Information System (INIS)

Souza Mansur, E. de.

1988-01-01

An in vitro study was performed to determine the solubility of the yellow cake produced in a Brazilian uranium mill to permit classification of the inhaled material and to aid bioassay interpretation. The powder was taken from 6 different lots of yellow cake produced during 10 weeks mill operation period. Dissolution fractions and half-times were obtained using simulated lung fluid in a shaker bath at 37 0 C for 30 days. Uranium concentration were determined by neutron activation analysis. (author)

Direct heat transfer considerations for improving energy efficiency in pulp and paper Kraft mills

Energy Technology Data Exchange (ETDEWEB)

Savulescu, Luciana Elena; Alva-Argaez, Alberto [Natural Resources (Canada)

2008-10-15

The success of any process improvement study depends on the quality of the available data and the way in which the plant-specific characteristics are incorporated in the applied conceptual models; in the context of process integration studies these issues are directly related to the rules followed during the data extraction stage. Improving energy efficiency in a pulp and paper Kraft mill requires the identification of the most promising heat recovery network retrofit projects. In a retrofit analysis using pinch technology/process integration methods, only the process streams associated to the existing heat exchangers and some outlet streams (such as wastewater/effluent streams and vents) with high potential for heat recovery are usually included, while the energy exchanged through non-isothermal stream mixing (NIM) or direct heat transfer (DHT) is often assumed fixed and is not considered in the analysis. Relaxing this assumption requires extracting more data to represent the DHT design configuration that exists in the plant. However, different data extraction options can be considered to represent the DHT configuration depending on the associated process/operation constraints. This work describes a systematic procedure to extract and analyse the impacts of DHT on the overall energy efficiency of a Kraft process with a specific focus on mixing along the pulp line and in water tanks. (author)

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

Decontamination effect of milling by a jet mill on bacteria in rice flour.

Science.gov (United States)

Sotome, Itaru; Nei, Daisuke; Tsuda, Masuko; Mohammed, Sharif Hossen; Takenaka, Makiko; Okadome, Hiroshi; Isobe, Seiichiro

2011-06-01

The decontamination effect of milling by a jet mill was investigated by counting the number of bacteria in brown and white rice flour with mean particle diameters of 3, 20, and 40µm prepared by the jet mill. In the jet mill, the particles are crushed and reduced in size by the mechanical impact caused by their collision. Although the brown and white rice grains were contaminated with approximately 10(6) and 10(5) CFU/g bacteria, the microbial load of the rice flour decreased as the mean particle diameter decreased, ultimately decreasing to approximately 104 and 103 CFU/g in the brown and white rice flour. The temperature and pressure changes of the sample were not considered to have an effect on reducing the bacterial count during the milling. Hence, it was thought that the rice flour was decontaminated by other effects.

Comprehensive characterization of ball-milled powders simulating a tribofilm system

Energy Technology Data Exchange (ETDEWEB)

Häusler, I., E-mail: ines.haeusler@bam.de; Dörfel, I., E-mail: Ilona.doerfel@bam.de; Peplinski, B., E-mail: Burkhard.peplinski@bam.de; Dietrich, P.M., E-mail: Paul.dietrich@yahoo.de; Unger, W.E.S., E-mail: Wolfgang.Unger@bam.de; Österle, W., E-mail: Werner.Oesterle@bam.de

2016-01-15

A model system was used to simulate the properties of tribofilms which form during automotive braking. The model system was prepared by ball milling of a blend of 70 vol.% iron oxides, 15 vol.% molybdenum disulfide and 15 vol.% graphite. The resulting mixture was characterized by X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and various transmission electron microscopic (TEM) methods, including energy dispersive X-ray spectroscopy (EDXS), high resolution investigations (HRTEM) with corresponding simulation of the HRTEM images, diffraction methods such as scanning nano-beam electron diffraction (SNBED) and selected area electron diffraction (SAED). It could be shown that the ball milling caused a reduction of the grain size of the initial components to the nanometer range. Sometimes even amorphization or partial break-down of the crystal structure was observed for MoS{sub 2} and graphite. Moreover, chemical reactions lead to a formation of surface coverings of the nanoparticles by amorphous material, molybdenum oxides, and iron sulfates as derived from XPS. - Highlights: • Ball milling of iron oxides, MoS{sub 2}, and graphite to simulate a tribofilm • Increasing coefficient of friction after ball milling of the model blend • Drastically change of the diffraction pattern of the powder mixture • TEM & XPS showed the components of the milled mixture and the process during milling. • MoS{sub 2} and graphite suffered a loss in translation symmetry or became amorphous.

New Nanoparticles Dispersing Beads Mill with Ultra Small Beads and its Application

International Nuclear Information System (INIS)

Inkyo, M; Tahara, T; Imajyo, Y

2011-01-01

Two of the major problems related to nanoparticle dispersion with a conventional beads mill are re-agglomeration and damage to the crystalline structure of the particles. The Ultra Apex Mill was developed to solve these problems by enabling the use of ultra-small beads with a diameter of less than 0.1mm. The core of this breakthrough development is centrifugation technology which allows the use of beads as small as 0.015mm. When dispersing agglomerated nanoparticles the impulse of the small beads is very low which means there is little influence on the particles. The surface energy of the nanoparticles remains low so the properties are not likely to change. As a result, stable nanoparticle dispersions can be achieved without re-cohesion. The Ultra Apex Mill is superior to conventional beads mills that are limited to much larger bead sizes. The technology of the Ultra Apex Mill has pioneered practical applications for nanoparticles in various fields: composition materials for LCD screens, ink-jet printing, ceramic condensers and cosmetics.

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.

Hybrid ABC Optimized MARS-Based Modeling of the Milling Tool Wear from Milling Run Experimental Data

OpenAIRE

Garc?a Nieto, Paulino Jos?; Garc?a-Gonzalo, Esperanza; Ord??ez Gal?n, Celestino; Bernardo S?nchez, Antonio

2016-01-01

Milling cutters are important cutting tools used in milling machines to perform milling operations, which are prone to wear and subsequent failure. In this paper, a practical new hybrid model to predict the milling tool wear in a regular cut, as well as entry cut and exit cut, of a milling tool is proposed. The model was based on the optimization tool termed artificial bee colony (ABC) in combination with multivariate adaptive regression splines (MARS) technique. This optimization mechanism i...

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)

The isotropic local Wigner-Seitz model: An accurate theoretical model for the quasi-free electron energy in fluids

Science.gov (United States)

Evans, Cherice; Findley, Gary L.

The quasi-free electron energy V0 (ρ) is important in understanding electron transport through a fluid, as well as for modeling electron attachment reactions in fluids. Our group has developed an isotropic local Wigner-Seitz model that allows one to successfully calculate the quasi-free electron energy for a variety of atomic and molecular fluids from low density to the density of the triple point liquid with only a single adjustable parameter. This model, when coupled with the quasi-free electron energy data and the thermodynamic data for the fluids, also can yield optimized intermolecular potential parameters and the zero kinetic energy electron scattering length. In this poster, we give a review of the isotropic local Wigner-Seitz model in comparison to previous theoretical models for the quasi-free electron energy. All measurements were performed at the University of Wisconsin Synchrotron Radiation Center. This work was supported by a Grants from the National Science Foundation (NSF CHE-0956719), the Petroleum Research Fund (45728-B6 and 5-24880), the Louisiana Board of Regents Support Fund (LEQSF(2006-09)-RD-A33), and the Professional Staff Congress City University of New York.

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.

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.)

Effect of mechanical milling on barium titanate (BaTiO3) perovskite

Science.gov (United States)

Singh, Rajan Kumar; Sanodia, Sagar; Jain, Neha; Kumar, Ranveer

2018-05-01

Commercial Barium Titanate BaTiO3 (BT) is milled by planetary ball mill in acetone medium using stainless steel bowl & ball for different hours. BT is an important perovskite oxide with structure ABO3. BT has applications in electro-optic devices, energy storing devices such as photovoltaic cells, thermistors, multiceramic capacitors & DRAMs etc. BT is non-toxic & environment friendly ceramic with high dielectric and piezoelectric property so it can be used as the substitute of PZT & PbTiO3. Here, we have investigated the effect of milling time and temperature on particle size and phase transition of BT powder. We used use Raman spectroscopy for studying the spectra of BT; XRD is used for structural study. Intensity (height) of Raman spectra and XRD spectra continuously decrease with increasing the milling hours and width if these spectra increases which indicates, decrease in BT size.

Beneficial uses of paper mill residuals for New York State`s recycled-paper mills. Final report

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-09-01

This report evaluates the New York paper mill industry in terms of the productive management and treatment of solid wastes. It identifies current efforts by recycling mills to beneficially use paper mill residuals (often called sludge) and suggests additional options that should be considered by the industry in general and individual mills in particular. It also examines the regulations and economics affecting the mills and suggests actions that could improve the industry`s ability to convert wastes to value-added products. The report recommends that the mills should continue measures to reduce fiber and filler clay losses, promote the transfer of usable fiber and clay to mills able to use them, upgrade sludge dewatering capabilities, and take a more regional approach to solid waste disposal problems. State agencies are urged to support these efforts, encourage the development and commercialization of new beneficial use technologies, and reduce regulatory barriers whenever possible.

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.

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.

XRD and HREM studies from the decomposition of icosahedral AlCuFe single-phase by high-energy ball milling

International Nuclear Information System (INIS)

Patino-Carachure, C.; Tellez-Vazquez, O.; Rosas, G.

2011-01-01

Highlights: → Point defects induced during milling leading to an order-disorder quasicrystal transition. → Nanoquasicrystalline regions of 12 nm are obtained. → Highly ordered i-phase with high symmetry transforms to a crystalline phase of intermetallic character and lower symmetry. - Abstract: In this investigation the Al 64 Cu 24 Fe 12 alloy was melted in an induction furnace and solidified under normal casting conditions. In order to obtain the icosahedral phase (i-phase) in a single-phase region, the as-cast sample was subject to a heat treatment at 700 deg. C under argon atmosphere. Subsequently, the i-phase was milled for different times in order to evaluate phase stability under heavy deformation. X-ray diffraction (XRD) and high-resolution electron microscopy (HREM) analysis were conducted to the structural characterization of ball-milled powders. XRD results indicated a reduction in quasicrystal size during mechanical ball milling to about 30 h. HREM analysis revealed the presence of aperiodic nano-domains, for example, with apparent fivefold symmetry axis. Therefore, the i-phase remains stable over the first 30 h of ball-milling time. However, among 30-50 h of mechanical milling the i-phase transforms progressively into β-cubic phase.

XRD and HREM studies from the decomposition of icosahedral AlCuFe single-phase by high-energy ball milling

Energy Technology Data Exchange (ETDEWEB)

Patino-Carachure, C.; Tellez-Vazquez, O. [Instituto de Investigaciones Metalurgicas, UMSNH, Edificio U, Ciudad Universitaria, Morelia, Michoacan 58000 (Mexico); Rosas, G., E-mail: grtrejo@umich.mx [Instituto de Investigaciones Metalurgicas, UMSNH, Edificio U, Ciudad Universitaria, Morelia, Michoacan 58000 (Mexico)

2011-10-13

Highlights: > Point defects induced during milling leading to an order-disorder quasicrystal transition. > Nanoquasicrystalline regions of 12 nm are obtained. > Highly ordered i-phase with high symmetry transforms to a crystalline phase of intermetallic character and lower symmetry. - Abstract: In this investigation the Al{sub 64}Cu{sub 24}Fe{sub 12} alloy was melted in an induction furnace and solidified under normal casting conditions. In order to obtain the icosahedral phase (i-phase) in a single-phase region, the as-cast sample was subject to a heat treatment at 700 deg. C under argon atmosphere. Subsequently, the i-phase was milled for different times in order to evaluate phase stability under heavy deformation. X-ray diffraction (XRD) and high-resolution electron microscopy (HREM) analysis were conducted to the structural characterization of ball-milled powders. XRD results indicated a reduction in quasicrystal size during mechanical ball milling to about 30 h. HREM analysis revealed the presence of aperiodic nano-domains, for example, with apparent fivefold symmetry axis. Therefore, the i-phase remains stable over the first 30 h of ball-milling time. However, among 30-50 h of mechanical milling the i-phase transforms progressively into {beta}-cubic phase.

Effect of Milling Condition on the Microstructure and the Properties of Nano structured Copper Tungsten Carbide Composite

International Nuclear Information System (INIS)

Mahani Yusoff; Zuhailawati Hussain

2011-01-01

In this work, in-situ Cu-WC composite has been fabricated by high energy milling followed by sintering. Cu, W and C mixture were mechanically alloyed in a planetary ball mill for 40 h at various milling speeds. Cu-W-C composite powders were cold compacted and sintered in argon ambient. Milled powder and sintered Cu-W-C composite were characterized in terms of Xray diffraction (XRD), field emission scanning electron microscopy (FESEM) and its properties. The result showed that carbide phases are only detected after sintering process. Greater amount of grain refinement during milling generates very high internal strain which reduced Cu crystallite size. It was found that formation of metastable, W 2 C has taken place before the formation of WC. With the presence of WC, the composite become increasingly harden with the increased of milling speed. Increasing milling speed also found to lower the electrical conductivity. (author)

Overview of milling techniques for improving the solubility of poorly water-soluble drugs

Directory of Open Access Journals (Sweden)

Zhi Hui Loh

2015-07-01

Full Text Available Milling involves the application of mechanical energy to physically break down coarse particles to finer ones and is regarded as a “top–down” approach in the production of fine particles. Fine drug particulates are especially desired in formulations designed for parenteral, respiratory and transdermal use. Most drugs after crystallization may have to be comminuted and this physical transformation is required to various extents, often to enhance processability or solubility especially for drugs with limited aqueous solubility. The mechanisms by which milling enhances drug dissolution and solubility include alterations in the size, specific surface area and shape of the drug particles as well as milling-induced amorphization and/or structural disordering of the drug crystal (mechanochemical activation. Technology advancements in milling now enable the production of drug micro- and nano-particles on a commercial scale with relative ease. This review will provide a background on milling followed by the introduction of common milling techniques employed for the micronization and nanonization of drugs. Salient information contained in the cited examples are further extracted and summarized for ease of reference by researchers keen on employing these techniques for drug solubility and bioavailability enhancement.

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)

Influence of milling parameters on the sorption properties of the LiH–MgB{sub 2} system doped with TiCl{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Busch, Nina; Jepsen, Julian; Pistidda, Claudio [Institute of Materials Research, Helmholtz-Zentrum Geesthacht, Max-Planck-Straße 1, D-21502 Geesthacht (Germany); Puszkiel, Julián A. [Institute of Materials Research, Helmholtz-Zentrum Geesthacht, Max-Planck-Straße 1, D-21502 Geesthacht (Germany); Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Combatientes de Malvinas 3150, 1427 Buenos Aires (Argentina); Karimi, Fahim [Institute of Materials Research, Helmholtz-Zentrum Geesthacht, Max-Planck-Straße 1, D-21502 Geesthacht (Germany); Milanese, Chiara [Pavia H_2 Lab, Department of Chemistry, Physical Chemistry Division, University of Pavia, Viale Taramelli 16, I-27100 Pavia (Italy); Tolkiehn, Martin [SRXPD Beamline HASYLAB, Deutsches-Elektronen-Synchrotron DESY, Notkestrasse 85, D-22607 Hamburg (Germany); Chaudhary, Anna-Lisa, E-mail: anna-lisa.chaudhary@hzg.de [Institute of Materials Research, Helmholtz-Zentrum Geesthacht, Max-Planck-Straße 1, D-21502 Geesthacht (Germany); Klassen, Thomas; Dornheim, Martin [Institute of Materials Research, Helmholtz-Zentrum Geesthacht, Max-Planck-Straße 1, D-21502 Geesthacht (Germany)

2015-10-05

Highlights: • The LiH–MgB{sub 2} system was doped with TiCl{sub 3} and milling conditions varied. • A heuristic model was used to estimate energy transfer from milling conditions. • Milling parameters were correlated with the energy transfer calculation. • 20 kJ g{sup −1} of energy transfer correlates to the optimum conditions for the system. - Abstract: Hydrogen sorption properties of the LiH–MgB{sub 2} system doped with TiCl{sub 3} were investigated with respect to milling conditions (milling times, ball to powder (BTP) ratios, rotation velocities and degrees of filling) to form the reactive hydride composite (RHC) LiBH{sub 4}–MgH{sub 2}. A heuristic model was applied to approximate the energy transfer from the mill to the powders. These results were linked to experimentally obtained quantities such as crystallite size, specific surface area (SSA) and homogeneity of the samples, using X-ray diffraction (XRD), the Brunauer–Emmett–Teller (BET) method and scanning electron microscopy (SEM), respectively. The results show that at approximately 20 kJ g{sup −1} there are no further benefits to the system with an increase in energy transfer. This optimum energy transfer value indicates that a plateau was reached for MgB{sub 2} crystallite size therefore the there was also no improvement of reaction kinetics due to no change in crystallite size. Therefore, this study shows that an optimum energy transfer value was reached for the LiH–MgB{sub 2} system doped with TiCl{sub 3}.

Alloying and microstructural changes in platinum–titanium milled and annealed powders

International Nuclear Information System (INIS)

Maweja, Kasonde; Phasha, M.J.; Yamabe-Mitarai, Y.

2012-01-01

Graphical abstract: (a) SE-SEM micrographs of PtTi martensite formed in powder milled for short time annealed at 1500 °C and quenched in helium gas flow (b) BSE-SEM of structure formed after slow cooling. Highlights: ► A disordered metastable FCC Pt(Ti) solid solution was formed after longer milling period. ► HCP Ti crystals were first deformed and then the atoms were dissolved in strained FCC Pt lattices. ► Longer milling time suppressed the occurrence of martensitic transformation after annealing. ► Martensite phase was formed in products that went through a short milling time then annealed and quenched. ► The width of the martensite features formed was smaller at higher cooling rates. - Abstract: Equiatomic platinum–titanium powder mixtures were processed by high energy ball milling under argon atmosphere and sintered under vacuum. Evolution of the crystal structures and microstructures of the products formed were investigated by XRD and SEM techniques, respectively. The HCP crystals of Ti were first deformed and then a disordered metastable FCC Pt(Ti) solid solution was formed during milling due to semi-coherency of FCC lattices. A nanostructured Pt(Ti) product was formed after long milling time, which contained 44–47 at.% Ti and 53–56 at.% Pt. An ordered PtTi intermetallic was formed by annealing the metastable Pt(Ti) at temperature above 1300 °C. The crystal structure and microstructure of the TiPt phase depended on the milling time, annealing temperature and the cooling rate. The B19 PtTi plate martensite was formed after annealing at 1500 °C and quenching at a cooling rate of 23 °C/min to 200 °C/min for short time milled products. The width of martensite features was smaller at high cooling rate. In PtTi products milled for longer time, no martensitic transformation was observed on cooling the annealed samples. Small amounts of Pt 5 Ti 3 were formed in the powders milled for 16 h or more, followed by annealing at 1500 °C and furnace

Airborne effluent control at uranium mills

International Nuclear Information System (INIS)

Sears, M.B.

1976-01-01

The Oak Ridge National Laboratory has made an engineering cost--environmental benefit study of radioactive waste treatment systems for decreasing the amount of radioactive materials released from uranium ore processing mills. This paper summarizes the results of the study which pertain to the control and/or abatement of airborne radioactive materials from the mill processes. The tailings area is not included. Present practices in the uranium milling industry, with particular emphasis on effluent control and waste management, have been surveyed. A questionnaire was distributed to each active mill in the United States. Replies were received from about 75 percent of the mill operators. Visits were made to six operating uranium mills that were selected because they represented the different processes in use today and the newest, most modern in mill designs. Discussions were held with members of the Region IV Office of NRC and the Grand Junction Office of ERDA. Nuclear Science Abstracts, as well as other sources, were searched for literature pertinent to uranium mill processes, effluent control, and waste management

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 ...

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)

TEM characterization of Al-C-Cu-Al2O3 composites produced by mechanical milling

International Nuclear Information System (INIS)

Santos-Beltran, A.; Gallegos-Orozco, V.; Estrada-Guel, I.; Bejar-Gomez, L.; Espinosa-Magana, F.; Miki-Yoshida, M.; Martinez-Sanchez, R.

2007-01-01

Novel Al-based composites (Al-C-Cu-Al 2 O 3 ) obtained by mechanical milling (MM), were characterized by transmission electron microscopy (TEM) and electron energy loss spectroscopy (EELS). Analyses of composites were carried out in both, the as-milled and the as-sintered conditions. C nanoparticles were found in the as-milled condition and Al 2 O 3 nanofibers were found in as-sintered products, as determined by EELS. C and Cu react with Al to crystallize in Al 3 C 4 and Al 2 Cu structures, respectively

Characterization of high-energy milled alumina powders Caracterização de pós de alumina submetidos a moagem de alta energia

Directory of Open Access Journals (Sweden)

Roberto Tomasi

1998-10-01

Full Text Available The utilization of reactive high-energy milling has been reported for the synthesis of ceramic powders namely, metal oxides, carbides, borides, nitrides or mixtures of ceramics or ceramic and metal compounds. In this work, high-energy milling was used for reduction of alumina powders to nanometric particle size. The ceramic characteristics of the powders were analyzed in terms of the behavior during deagglomeration, compaction curves, sintering and microstructure characterization. It was observed that the high energy milling has strong effect in producing agglomeration of the nanosized powders. This effect is explained by the high-energy impact of the balls, which may fracture particles or just cause the particles compacting. In this case, strong agglomerates are produced. As the powder surface area increases, stronger agglomerates are produced.Tem sido amplamente divulgada a utilização da moagem reativa de alta energia para a síntese de pós cerâmicos de óxidos de metais, carbetos, boretos, nitretos ou misturas de compostos cerâmicos ou compostos cerâmicos e metálicos. Neste trabalho, a moagem de alta energia (não reativa foi utilizada para a redução de pós de alumina para partículas de dimensões nanométricas. As características cerâmicas dos pós obtidos foram analisadas a partir de resultados de comportamento durante a desaglomeração, curvas de densificação, sinterização e caracterização de microestrutura. Observou-se que a moagem de alta energia tem forte efeito de aglomeração dos pós com partículas em dimensões nanométricas. Esse efeito é explicado pelo impacto de alta energia das bolas, os quais podem fraturar as partículas ou apenas causar a compactação das mesmas. Nesse último caso, que sempre ocorre, são formados aglomerados de alta resistência. O aumento da área superficial do pó produz aglomerados mais resistentes.

Torrefied Biomass Pellets—Comparing Grindability in Different Laboratory Mills

Directory of Open Access Journals (Sweden)

Jan Hari Arti Khalsa

2016-10-01

Full Text Available The firing and co-firing of biomass in pulverized coal fired power plants around the world is expected to increase in the coming years. Torrefaction may prove to be a suitable way of upgrading biomass for such an application. For transport and storage purposes, the torrefied biomass will tend to be in pellet form. Whilst standard methods for the assessment of the milling characteristics of coal exist, this is not the case for torrefied materials—whether in pellet form or not. The grindability of the fuel directly impacts the overall efficiency of the combustion process and as such it is an important parameter. In the present study, the grindability of different torrefied biomass pellets was tested in three different laboratory mill types; cutting mill (CM, hammer mill (HM and impact mill (IM. The specific grinding energy (SGE required for a defined mass throughput of pellets in each mill was measured and results were compared to other pellet characterization methods (e.g., durability, and hardness as well as the modified Hardgrove Index. Seven different torrefied biomass pellets including willow, pine, beech, poplar, spruce, forest residue and straw were used as feedstock. On average, the particle-size distribution width (across all feedstock was narrowest for the IM (0.41 mm, followed by the HM (0.51 mm and widest for the CM (0.62 mm. Regarding the SGE, the IM consumed on average 8.23 Wh/kg while CM and HM consumed 5.15 and 5.24 Wh/kg, respectively. From the three mills compared in this study, the IM seems better fit for being used in a standardized method that could be developed in the future, e.g., as an ISO standard.

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.

Monte Carlo simulations of secondary electron emission due to ion beam milling

Energy Technology Data Exchange (ETDEWEB)

Mahady, Kyle [Univ. of Tennessee, Knoxville, TN (United States); Tan, Shida [Intel Corp., Santa Clara, CA (United States); Greenzweig, Yuval [Intel Israel Ltd., Haifa (Israel); Livengood, Richard [Intel Corp., Santa Clara, CA (United States); Raveh, Amir [Intel Israel Ltd., Haifa (Israel); Fowlkes, Jason D. [Univ. of Tennessee, Knoxville, TN (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Rack, Philip [Univ. of Tennessee, Knoxville, TN (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2017-07-01

We present a Monte Carlo simulation study of secondary electron emission resulting from focused ion beam milling of a copper target. The basis of this study is a simulation code which simulates ion induced excitation and emission of secondary electrons, in addition to simulating focused ion beam sputtering and milling. This combination of features permits the simulation of the interaction between secondary electron emission, and the evolving target geometry as the ion beam sputters material. Previous ion induced SE Monte Carlo simulation methods have been restricted to predefined target geometries, while the dynamic target in the presented simulations makes this study relevant to image formation in ion microscopy, and chemically assisted ion beam etching, where the relationship between sputtering, and its effects on secondary electron emission, is important. We focus on a copper target, and validate our simulation against experimental data for a range of: noble gas ions, ion energies, ion/substrate angles and the energy distribution of the secondary electrons. We then provide a detailed account of the emission of secondary electrons resulting from ion beam milling; we quantify both the evolution of the yield as high aspect ratio valleys are milled, as well as the emission of electrons within these valleys that do not escape the target, but which are important to the secondary electron contribution to chemically assisted ion induced etching.

Rough mill simulator version 3.0: an analysis tool for refining rough mill operations

Science.gov (United States)

Edward Thomas; Joel Weiss

2006-01-01

ROMI-3 is a rough mill computer simulation package designed to be used by both rip-first and chop-first rough mill operators and researchers. ROMI-3 allows users to model and examine the complex relationships among cutting bill, lumber grade mix, processing options, and their impact on rough mill yield and efficiency. Integrated into the ROMI-3 software is a new least-...

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...... will present measurements comparing pressure dynamics for two valve opening algorithms. In addition the paper will give a theoretical investigation of the energy loss during valve shifting and finally measurements of average power output from the power take-off system in various sea states are compared...

Process optimization and particle engineering of micronized drug powders via milling.

Science.gov (United States)

Brunaugh, A; Smyth, H D C

2017-11-13

Process control and optimization is a critical aspect of process analytical technology (PAT), quality by design (QbD), and the implementation of continuous manufacturing procedures. While process control and optimization techniques have been utilized in other manufacturing industries for decades, the pharmaceutical industry has only recently begun to adopt these procedures. Micronization, particularly milling, is a generally low-yield, high-energy consumption process that is well suited for a process optimization mindset. This review discusses optimization of the pharmaceutical milling process through design space development, theoretical and empirical modeling, and monitoring of critical quality attributes.

Drilling Fluids Using Multiwall Carbon Nanotube (MWCNT

Directory of Open Access Journals (Sweden)

Mostafa Sedaghatzadeh

2012-11-01

Full Text Available Designing drilling fluids for drilling in deep gas reservoirs and geothermal wells is a major challenge. Cooling drilling fluids and preparing stable mud with high thermal conductivity are of great concern. Drilling nanofluids, i.e. a low fraction of carbon nanotube (CNT well dispersed in mud, may enhance the mixture thermal conductivity compared to the base fluids. Thus, they are potentially useful for advanced designing high temperature and high pressure (HTHP drilling fluids. In the present study, the impacts of CNT volume fraction, ball milling time, functionalization, temperature, and dispersion quality (by means of scanning electron microscopy, SEM on the thermal and rheological properties of water-based mud are experimentally investigated. The thermal conductivities of the nano-based drilling fluid are measured with a transient hot wire method. The experimental results show that the thermal conductivity of the water-based drilling fluid is enhanced by 23.2% in the presence of 1 vol% functionalized CNT at room temperature; it increases by 31.8% by raising the mud temperature to 50 °C. Furthermore, significant improvements are seen in the rheological properties—such as yield point, filtration properties, and annular viscosity—of the CNTmodified drilling fluid compared to the base mud, which pushes forward their future development.

Hybrid ABC Optimized MARS-Based Modeling of the Milling Tool Wear from Milling Run Experimental Data.

Science.gov (United States)

García Nieto, Paulino José; García-Gonzalo, Esperanza; Ordóñez Galán, Celestino; Bernardo Sánchez, Antonio

2016-01-28

Milling cutters are important cutting tools used in milling machines to perform milling operations, which are prone to wear and subsequent failure. In this paper, a practical new hybrid model to predict the milling tool wear in a regular cut, as well as entry cut and exit cut, of a milling tool is proposed. The model was based on the optimization tool termed artificial bee colony (ABC) in combination with multivariate adaptive regression splines (MARS) technique. This optimization mechanism involved the parameter setting in the MARS training procedure, which significantly influences the regression accuracy. Therefore, an ABC-MARS-based model was successfully used here to predict the milling tool flank wear (output variable) as a function of the following input variables: the time duration of experiment, depth of cut, feed, type of material, etc . Regression with optimal hyperparameters was performed and a determination coefficient of 0.94 was obtained. The ABC-MARS-based model's goodness of fit to experimental data confirmed the good performance of this model. This new model also allowed us to ascertain the most influential parameters on the milling tool flank wear with a view to proposing milling machine's improvements. Finally, conclusions of this study are exposed.

Hybrid ABC Optimized MARS-Based Modeling of the Milling Tool Wear from Milling Run Experimental Data

Directory of Open Access Journals (Sweden)

Paulino José García Nieto

2016-01-01

Full Text Available Milling cutters are important cutting tools used in milling machines to perform milling operations, which are prone to wear and subsequent failure. In this paper, a practical new hybrid model to predict the milling tool wear in a regular cut, as well as entry cut and exit cut, of a milling tool is proposed. The model was based on the optimization tool termed artificial bee colony (ABC in combination with multivariate adaptive regression splines (MARS technique. This optimization mechanism involved the parameter setting in the MARS training procedure, which significantly influences the regression accuracy. Therefore, an ABC–MARS-based model was successfully used here to predict the milling tool flank wear (output variable as a function of the following input variables: the time duration of experiment, depth of cut, feed, type of material, etc. Regression with optimal hyperparameters was performed and a determination coefficient of 0.94 was obtained. The ABC–MARS-based model's goodness of fit to experimental data confirmed the good performance of this model. This new model also allowed us to ascertain the most influential parameters on the milling tool flank wear with a view to proposing milling machine's improvements. Finally, conclusions of this study are exposed.

Hybrid ABC Optimized MARS-Based Modeling of the Milling Tool Wear from Milling Run Experimental Data

Science.gov (United States)

García Nieto, Paulino José; García-Gonzalo, Esperanza; Ordóñez Galán, Celestino; Bernardo Sánchez, Antonio

2016-01-01

Milling cutters are important cutting tools used in milling machines to perform milling operations, which are prone to wear and subsequent failure. In this paper, a practical new hybrid model to predict the milling tool wear in a regular cut, as well as entry cut and exit cut, of a milling tool is proposed. The model was based on the optimization tool termed artificial bee colony (ABC) in combination with multivariate adaptive regression splines (MARS) technique. This optimization mechanism involved the parameter setting in the MARS training procedure, which significantly influences the regression accuracy. Therefore, an ABC–MARS-based model was successfully used here to predict the milling tool flank wear (output variable) as a function of the following input variables: the time duration of experiment, depth of cut, feed, type of material, etc. Regression with optimal hyperparameters was performed and a determination coefficient of 0.94 was obtained. The ABC–MARS-based model's goodness of fit to experimental data confirmed the good performance of this model. This new model also allowed us to ascertain the most influential parameters on the milling tool flank wear with a view to proposing milling machine's improvements. Finally, conclusions of this study are exposed. PMID:28787882

Fluctuating hydrodynamics for multiscale modeling and simulation: energy and heat transfer in molecular fluids.

Science.gov (United States)

Shang, Barry Z; Voulgarakis, Nikolaos K; Chu, Jhih-Wei

2012-07-28

This work illustrates that fluctuating hydrodynamics (FHD) simulations can be used to capture the thermodynamic and hydrodynamic responses of molecular fluids at the nanoscale, including those associated with energy and heat transfer. Using all-atom molecular dynamics (MD) trajectories as the reference data, the atomistic coordinates of each snapshot are mapped onto mass, momentum, and energy density fields on Eulerian grids to generate a corresponding field trajectory. The molecular length-scale associated with finite molecule size is explicitly imposed during this coarse-graining by requiring that the variances of density fields scale inversely with the grid volume. From the fluctuations of field variables, the response functions and transport coefficients encoded in the all-atom MD trajectory are computed. By using the extracted fluid properties in FHD simulations, we show that the fluctuations and relaxation of hydrodynamic fields quantitatively match with those observed in the reference all-atom MD trajectory, hence establishing compatibility between the atomistic and field representations. We also show that inclusion of energy transfer in the FHD equations can more accurately capture the thermodynamic and hydrodynamic responses of molecular fluids. The results indicate that the proposed MD-to-FHD mapping with explicit consideration of finite molecule size provides a robust framework for coarse-graining the solution phase of complex molecular systems.

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

Microstructure and properties of copper composite containing in situ NbC reinforcement: Effects of milling speed

International Nuclear Information System (INIS)

Zuhailawati, Hussain; Salihin, Hassin Mohd; Mahani, Yusoff

2010-01-01

This paper presents a study on the effects of milling speed on the properties of in situ copper-based composite produced by mechanical alloying followed by cold pressing and sintering. A powdered mixture of copper, niobium and graphite with the composition of Cu-30%NbC was milled at various speeds (100, 200, 300 and 400 rpm). The NbC phase started to precipitate in the as-milled powder after 30 h milling at 400 rpm and the formation was completed after sintering at 950 o C. Enhancements of NbC phase formation with a reduction in Cu crystallite size were observed with the increase of milling speed. Density, hardness and electrical conductivity of the sintered composite were evaluated. An increase in milling speed resulted in an increase in sintered density and hardness but a reduction of electrical conductivity. The changes in the properties were correlated to the formation of NbC phase and refinement of copper and niobium carbide crystallite size since higher milling speed is associated with higher kinetic energy per hit.

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%.

Uranium Mill Tailings Remedial Action Amendments Act of 1988. Introduced in the Senate, One Hundredth Congress, Second Session, Report 100-543, September 23, 1988

International Nuclear Information System (INIS)

Anon.

1988-01-01

The Committee on Energy and Natural Resources reported favorably on the Uranium Mill Tailings Remedial Action Amendments Act of 1987 (S.1991) with some amendments, the principal one being to change the 1987 date to 1988. The purpose of this bill is to authorize the Secretary of the Interior to transfer lands under the jurisdiction of the Bureau of Land Management to the Department of Energy for permanent surveillance and maintenance of remediated mill tailings as required by the Uranium Mill Tailings Radiation Control Act of 1978. The bill also extends the authority of the Secretary of Energy to perform remedial action at designated uranium mill tailings sites and vicinity properties until 30 September 1994. The authority to perform groundwater restoration activities is extended without limitation

Reducibility mill scale industrial waste via coke breeze at 850-950ºC

Directory of Open Access Journals (Sweden)

Gaballah N.M.

2015-01-01

Full Text Available Mill scale is a very attractive industrial waste due to its elevated iron content (about = 69.33% Fe besides being suiTab. for direct recycling to the blast furnace via sintering plant. In this paper the characteristics of raw materials and the briquettes produced from this mill scale were studied by different methods of analyses. The produced briquettes were reduced with different amounts of coke breeze at varying temperatures, and the reduction kinetics was determined. The activation energy of this reaction ≈ 61.5 kJ/mole for reduction of mill scale with coke breeze in the form of briquettes with 2% molasses where the chemical reaction interface model is applicable.

Development of hemicelluloses biorefineries for integration into kraft pulp mills

Science.gov (United States)

Ajao, Olumoye Abiodun

The development and wide spread acceptance of production facilities for biofuels, biochemicals and biomaterials is an important condition for reducing reliance on limited fossil resources and transitioning towards a global biobased economy. Pulp and paper mills in North America are confronted with high energy prices, high production costs and intense competition from emerging economies and low demand for traditional products. Integrated forest biorefineries (IFBR) have been proposed as a mean to diversify their product streams, increase their revenue and become more sustainable. This is feasible because they have access to forest biomass, an established feedstock supply chain and wood processing experience. In addition, the integration of a biorefinery process that can share existing infrastructure and utilities on the site of pulp mill would significantly lower investment cost and associated risks. Kraft pulping mills are promising receptor processes for a biorefinery because they either possess a prehydrolysis step for extracting hemicelluloses sugars prior to wood pulping or it can be added by retrofit. The extracted hemicelluloses could be subsequently transformed into a wide range of value added products for the receptor mill. To successfully implement hemicelluloses biorefinery, novel processes that are technically and economically feasible are required. It is necessary to identify products that would be profitable, develop processes that are energy efficient and the receptor mill should be able to supply the energy, chemicals and material demands of the biorefinery unit. The objective of this thesis is to develop energy efficient and economically viable hemicelluloses biorefineries for integration into a Kraft pulping process. A dissolving pulp mill was the reference case study. The transformation of hemicellulosic sugars via a chemical and biochemical conversion pathway, with furfural and ethanol as representative products for each pathway was studied. In

The Uhlenbeck-Ford model: Exact virial coefficients and application as a reference system in fluid-phase free-energy calculations

Science.gov (United States)

Paula Leite, Rodolfo; Freitas, Rodrigo; Azevedo, Rodolfo; de Koning, Maurice

2016-11-01

The Uhlenbeck-Ford (UF) model was originally proposed for the theoretical study of imperfect gases, given that all its virial coefficients can be evaluated exactly, in principle. Here, in addition to computing the previously unknown coefficients B11 through B13, we assess its applicability as a reference system in fluid-phase free-energy calculations using molecular simulation techniques. Our results demonstrate that, although the UF model itself is too soft, appropriately scaled Uhlenbeck-Ford (sUF) models provide robust reference systems that allow accurate fluid-phase free-energy calculations without the need for an intermediate reference model. Indeed, in addition to the accuracy with which their free energies are known and their convenient scaling properties, the fluid is the only thermodynamically stable phase for a wide range of sUF models. This set of favorable properties may potentially put the sUF fluid-phase reference systems on par with the standard role that harmonic and Einstein solids play as reference systems for solid-phase free-energy calculations.

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.)

Fluid mechanics relevant to flow through pretreatment of cellulosic biomass.

Science.gov (United States)

Archambault-Léger, Véronique; Lynd, Lee R

2014-04-01

The present study investigates fluid mechanical properties of cellulosic feedstocks relevant to flow through (FT) pretreatment for biological conversion of cellulosic biomass. The results inform identifying conditions for which FT pretreatment can be implemented in a practical context. Measurements of pressure drop across packed beds, viscous compaction and water absorption are reported for milled and not milled sugarcane bagasse, switchgrass and poplar, and important factors impacting viscous flow are deduced. Using biomass knife-milled to pass through a 2mm sieve, the observed pressure drop was highest for bagasse, intermediate for switchgrass and lowest for poplar. The highest pressure drop was associated with the presence of more fine particles, greater viscous compaction and the degree of water absorption. Using bagasse without particle size reduction, the instability of the reactor during pretreatment above 140kg/m(3) sets an upper bound on the allowable concentration for continuous stable flow. Copyright © 2014. Published by Elsevier Ltd.

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.

A multi-criteria decision analysis of management alternatives for anaerobically digested kraft pulp mill sludge.

Directory of Open Access Journals (Sweden)

Martijn Eikelboom

Full Text Available The Multi-Criteria Decision Analysis (MCDA procedure was used to compare waste management options for kraft pulp mill sludge following its anaerobic digestion. Anaerobic digestion of sludge is advantageous because it produces biogas that may be used to generate electricity, heat and biofuels. However, adequate management of the digested sludge is essential. Landfill disposal is a non-sustainable waste management alternative. Kraft pulp mill digested sludge applied to land may pose risks to the environment and public health if the sludge has not been properly treated. This study is aimed to compare several recycling alternatives for anaerobically digested sludge from kraft pulp mills: land application, landfill disposal, composting, incineration, pyrolysis/gasification, and biofuel production by algae. The MCDA procedure considered nine criteria into three domains to compare digested sludge recycling alternatives in a kraft pulp mill: environmental (CO2 emission, exposure to pathogens, risk of pollution, material and energy recovery, economic (overall costs, value of products and technical (maintenance and operation, feasibility of implementation. The most suitable management options for digested sludge from kraft pulp mills were found to be composting and incineration (when the latter was coupled with recycling ash to the cement industry. Landfill disposal was the worst option, presenting low performance in feasibility of implementation, risk of pollution, material and energy recovery.

A multi-criteria decision analysis of management alternatives for anaerobically digested kraft pulp mill sludge

Science.gov (United States)

Eikelboom, Martijn; Lopes, Alice do Carmo Precci; Silva, Claudio Mudadu; Rodrigues, Fábio de Ávila; Zanuncio, José Cola

2018-01-01

The Multi-Criteria Decision Analysis (MCDA) procedure was used to compare waste management options for kraft pulp mill sludge following its anaerobic digestion. Anaerobic digestion of sludge is advantageous because it produces biogas that may be used to generate electricity, heat and biofuels. However, adequate management of the digested sludge is essential. Landfill disposal is a non-sustainable waste management alternative. Kraft pulp mill digested sludge applied to land may pose risks to the environment and public health if the sludge has not been properly treated. This study is aimed to compare several recycling alternatives for anaerobically digested sludge from kraft pulp mills: land application, landfill disposal, composting, incineration, pyrolysis/gasification, and biofuel production by algae. The MCDA procedure considered nine criteria into three domains to compare digested sludge recycling alternatives in a kraft pulp mill: environmental (CO2 emission, exposure to pathogens, risk of pollution, material and energy recovery), economic (overall costs, value of products) and technical (maintenance and operation, feasibility of implementation). The most suitable management options for digested sludge from kraft pulp mills were found to be composting and incineration (when the latter was coupled with recycling ash to the cement industry). Landfill disposal was the worst option, presenting low performance in feasibility of implementation, risk of pollution, material and energy recovery. PMID:29298296

Surface Quality of Staggered PCD End Mill in Milling of Carbon Fiber Reinforced Plastics

Directory of Open Access Journals (Sweden)

Guangjun Liu

2017-02-01

Full Text Available Machined surface quality determines the reliability, wear resistance and service life of carbon fiber reinforced plastic (CFRP workpieces. In this work, the formation mechanism of the surface topography and the machining defects of CFRPs are proposed, and the influence of milling parameters and fiber cutting angles on the surface quality of CFRPs is obtained, which can provide a reference for extended tool life and good surface quality. Trimming and slot milling tests of unidirectional CFRP laminates are performed. The surface roughness of the machined surface is measured, and the influence of milling parameters on the surface roughness is analyzed. A regression model for the surface roughness of CFRP milling is established. A significance test of the regression model is conducted. The machined surface topography of milling CFRP unidirectional laminates with different fiber orientations is analyzed, and the effect of fiber cutting angle on the surface topography of the machined surface is presented by using a digital super depth-of-field microscope and scanning electron microscope (SEM. To study the influence of fiber cutting angle on machining defects, the machined topography under different fiber orientations is analyzed. The slot milling defects and their formation mechanism under different fiber cutting angles are investigated.

Effects of surfactant addition and high-speed ball milling on magnetic powders based on Pr-Fe-B obtained by HDDR

International Nuclear Information System (INIS)

Santos, Patricia Brissi

2011-01-01

This work verified the effect caused by adding the surfactant in the high speed/energy milling in order to obtain Pr 12 Fe 65.9 Co 16 B 6 Nb 0.1 magnetic nano powders. The first part of this work involved the magnetic powder obtainment through the process of hydrogenation, disproportionation, desorption and recombination (HDDR). The pressure of H2 during the hydrogenation and disproportion steps was 930 mbar and the temperature of desorption and recombination was 840 deg C. Initially, the HDDR powders were subjected a high speed milling process at 900 rpm, with quantity variations of the milling medium (cyclohexane) and without the addition of oleic acid. Then, the HDDR powders were subjected to the milling process with the addition of oleic acid and with milling time variations. After the milling process, heat treatments of the powder were carried out at 700 deg C or 800 deg C for 30 minutes in order to obtain the crystallization of the powder. By performing the procedures, it was verified that the milling efficiency improved with the addition of 6.6 ml of cyclohexane as the milling medium and with the addition of oleic acid. It was determined that for the surfactant additions of 0.02 ml to 0.05 ml, with a milling time of up to 360 minutes, powder agglomeration does not occur in the milling pot and the milling efficiency is higher than 90%. The second stage of this work involved the magnetic powder's characterization obtained by using vibrating sample magnetometer, scanning electron microscopy, transmission electron microscopy and X-ray diffraction. Through the characterizations it was found that the powder's magnetic properties improved when the addition of oleic acid in a high-speed /energy milling occurred. It was also verified that the α-Fe phase, present in the powder, shows a crystallite size decrease (from 35 nm to ∼ 10 nm) when the time milling variation occurred; meanwhile, the crystallinity degree was lower in the Pr 2 Fe 14 B phase when the time

Delamination of hexagonal boron nitride in a stirred media mill

International Nuclear Information System (INIS)

Damm, C.; Körner, J.; Peukert, W.

2013-01-01

A scalable process for delamination of hexagonal boron nitride in an aqueous solution of the non-ionic surfactant TWEEN85 using a stirred media mill is presented. The size of the ZrO 2 beads used as grinding media governs the dimensions of the ground boron nitride particles as atomic force microscopic investigations (AFM) reveal: the mean flakes thickness decreases from 3.5 to 1.5 nm and the ratio between mean flake area and mean flake thickness increases from 2,200 to 5,800 nm if the grinding media size is reduced from 0.8 to 0.1 mm. This result shows that a high number of stress events in combination with low stress energy (small grinding media) facilitate delamination of the layered material whereas at high stress energies in combination with a low number of stress events (large grinding media) breakage of the layers dominates over delamination. The results of particle height analyses by AFM show that few-layer structures have been formed by stirred media milling. This result is in agreement with the layer thickness dependence of the delamination energy for hexagonal boron nitride. The concentration of nanoparticles remaining dispersed after centrifugation of the ground suspension increases with grinding time and with decreasing grinding media size. After 5 h of grinding using 0.1 mm ZrO 2 grinding media the yield of nanoparticle formation is about 5 wt%. The nanoparticles exhibit the typical Raman peak for hexagonal boron nitride at 1,366 cm −1 showing that the in-plane order in the milled platelets is remained.

Sustainability of uranium mining and milling: toward quantifying resources and eco-efficiency.

Science.gov (United States)

Mudd, Gavin M; Diesendorf, Mark

2008-04-01

The mining of uranium has long been a controversial public issue, and a renewed debate has emerged on the potential for nuclear power to help mitigate against climate change. The central thesis of pro-nuclear advocates is the lower carbon intensity of nuclear energy compared to fossil fuels, although there remains very little detailed analysis of the true carbon costs of nuclear energy. In this paper, we compile and analyze a range of data on uranium mining and milling, including uranium resources as well as sustainability metrics such as energy and water consumption and carbon emissions with respect to uranium production-arguably the first time for modern projects. The extent of economically recoverable uranium resources is clearly linked to exploration, technology, and economics but also inextricably to environmental costs such as energy/water/chemicals consumption, greenhouse gas emissions, and social issues. Overall, the data clearly show the sensitivity of sustainability assessments to the ore grade of the uranium deposit being mined and that significant gaps remain in complete sustainability reporting and accounting. This paper is a case study of the energy, water, and carbon costs of uranium mining and milling within the context of the nuclear energy chain.

Yang-Mills gravity in biconformal space

International Nuclear Information System (INIS)

Anderson, Lara B; Wheeler, James T

2007-01-01

We write a gravity theory with Yang-Mills-type action using the biconformal gauging of the conformal group. We show that the resulting biconformal Yang-Mills gravity theories describe 4-dim, scale-invariant general relativity in the case of slowly changing fields. In addition, we systematically extend arbitrary 4-dim Yang-Mills theories to biconformal space, providing a new arena for studying flat-space Yang-Mills theories. By applying the biconformal extension to a 4-dim pure Yang-Mills theory with conformal symmetry, we establish a 1-1, onto mapping between a set of gravitational gauge theories and 4-dim, flat-space gauge theories

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

CSIR Research Space (South Africa)

Johakimu, Jonas K

2010-09-01

Full Text Available ). The mill’s screen fractionation process has limited efficiency. Substantial amounts of thick-walled fibres are present in the mill accept pulp samples (i.e. 66% by mass of the mill accept has a freeness of 256 ml CSF (Table 2)). The benefits of adding a...

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

Influence of rice sample preparation and milling procedures on milling quality appraisals

Science.gov (United States)

The objective of this research was to investigate the effect of sample preparation and milling procedure on milling quality appraisals of rough rice. Samples of freshly harvested medium-grain rice (M202) with different initial moisture contents (MCs) ranging from 20.2% to 25.1% (w.b.) were used for...

Effect of mechanical milling on the electrical and magnetic properties of nanostructured Ni0.5Zn0.5Fe2O4

International Nuclear Information System (INIS)

Sivakumar, N; Narayanasamy, A; Ponpandian, N; Greneche, J-M; Shinoda, K; Jeyadevan, B; Tohji, K

2006-01-01

Nanocrystalline Ni 0.5 Zn 0.5 Fe 2 O 4 spinel ferrite with a grain size of 50 nm was prepared by using the ceramic method. The grain size was further reduced to 14 nm by milling the as-prepared ferrite particles in a high-energy ball mill. From the impedance spectroscopy studies we have observed that the dc electrical conductivity increases upon milling. Furthermore, the cation distribution data, as obtained from the in-field Moessbauer and extended x-ray absorption fine structure measurements, suggested a decrease in the conductivity for the milled sample. The increase in conductivity of the milled sample is, therefore, attributed to conduction by the oxygen vacancies created by mechanical milling. The higher values obtained for the activation energy for conduction are also evidence for the oxygen vacancy conduction. The increase in Neel temperature from 573 to 611 K on reducing the grain size from 50 to 14 nm has been explained based on the changes in the cation distribution. The observed increase in the coercivity of the milled sample has been attributed to surface anisotropy of increasing number of ions on the surface. The Moessbauer spectra show canted spin structure for the milled samples

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.

The influence of the milling environment on the sintered structure of a W-Cu composite

International Nuclear Information System (INIS)

Costa, F.A.; Gomes, U.U.; Acchar, W.; Ambrozio Filho, F.; Silva, A.G.P.; Lima, S.J.G.

2009-01-01

This work reports an investigation about the influence of the environment of milling on the characteristics of the powders and on the structure and density of sintered samples made of these powders. Mixtures of composition W-30wt%Cu were milled for 51 hours in a high energy planetary mill in dry and wet (cyclohexane) conditions. The milled powders have composite particles. The powders were pressed and sintered at 1050 deg, 1150 deg and 1200 deg C under flowing hydrogen. The isothermal times were 0 minutes for the first two temperatures and 60 minutes for the latter. The samples reached around 95% of relative density. The powders were characterized by means of XRD and SEM. The sintered samples were characterized by means of SEM, optical microscopy and density measurement. (author)

Crystallite sizes of LiH before and after ball milling and thermal exposure

International Nuclear Information System (INIS)

Ortiz, Angel L.; Osborn, William; Markmaitree, Tippawan; Shaw, Leon L.

2008-01-01

The powder characteristics of lithium hydride (LiH) as a function of high-energy ball milling condition are systematically investigated via quantitative X-ray diffraction (XRD) analysis. The results obtained from the XRD analysis are compared with those attained from scanning electron microscopy (SEM), transmission electron microscopy (TEM), and specific surface area (SSA) analyses. The thermal stability of the ball-milled LiH is also investigated in order to provide physical insights into its cyclic stability in hydrogen sorption and desorption cycles. The results indicate that ball milling is effective in obtaining nano-crystalline LiH powder which is relatively stable with retention of nano-crystals after thermal exposure at 285 deg. C (equivalent to 0.58T m ) for 1 h. The good thermal stability observed is attributed to the presence of many pores in the agglomerates at the ball-milled condition. These pores effectively prevent crystal growth during the thermal exposure

Crystallite sizes of LiH before and after ball milling and thermal exposure

Energy Technology Data Exchange (ETDEWEB)

Ortiz, Angel L. [Departamento de Electronica e Ingenieria Electromecanica, Universidad de Extremadura, Badajoz (Spain); Osborn, William; Markmaitree, Tippawan [Department of Chemical, Materials and Biomolecular Engineering, University of Connecticut, 97 North Eagleville Road, U-3136 Storrs, CT 06269-3136 (United States); Shaw, Leon L. [Department of Chemical, Materials and Biomolecular Engineering, University of Connecticut, 97 North Eagleville Road, U-3136 Storrs, CT 06269-3136 (United States)], E-mail: leon.shaw@uconn.edu

2008-04-24

The powder characteristics of lithium hydride (LiH) as a function of high-energy ball milling condition are systematically investigated via quantitative X-ray diffraction (XRD) analysis. The results obtained from the XRD analysis are compared with those attained from scanning electron microscopy (SEM), transmission electron microscopy (TEM), and specific surface area (SSA) analyses. The thermal stability of the ball-milled LiH is also investigated in order to provide physical insights into its cyclic stability in hydrogen sorption and desorption cycles. The results indicate that ball milling is effective in obtaining nano-crystalline LiH powder which is relatively stable with retention of nano-crystals after thermal exposure at 285 deg. C (equivalent to 0.58T{sub m}) for 1 h. The good thermal stability observed is attributed to the presence of many pores in the agglomerates at the ball-milled condition. These pores effectively prevent crystal growth during the thermal exposure.

Tool Wear Analysis on Five-Axis Flank Milling for Curved Shape Part – Full Flute and Ground Shank End Mill

Directory of Open Access Journals (Sweden)

Syahrul Azwan Sundi

2017-01-01

Full Text Available This paper is a study on full flute (extra-long tool and ground shank end mill wear analysis by utilizing five-axis CNC to implement flank milling strategy on curved shape part. Five-axis machining eases the user to implement variations of strategy such as flank milling. Flank milling is different from point milling. Point milling cuts materials by using the tip of the tool whereas the flank milling uses the cutting tool body to cut material. The type of cutting tool used was end mill 10 mm diameter with High Speed Steel (HSS material. One factor at a time was utilized to analyze the overall data. Feed rate and spindle speed were the two main factors that been set up equally for both full flute and ground shank end mill. At the end of this research, the qualitative analysis based on tool wear between full flute and ground shank end mill is observed. Generally, both types of cutting tools showed almost the same failure indication such as broken edge or chipped off edge, formation of pinned hole on the surface and serration formation or built-up edge (BUE on the primary flute. However, the results obtained from the enlarged images which were captured by Optical Microscope indicated that, the ground shank end mill is better than the full flute end mill.

Production and characterization of cosmetic nanoemulsions containing Opuntia ficus-indica (L.) mill extract as moisturizing agent.

Science.gov (United States)

Ribeiro, Renato Cesar de Azevedo; Barreto, Stella Maria de Andrade Gomes; Ostrosky, Elissa Aarantes; da Rocha-Filho, Pedro Alves; Veríssimo, Lourena Mafra; Ferrari, Márcio

2015-02-02

This study aimed to produce and characterize an oil in water (O/W) nanoemulsion containing Opuntia ficus-indica (L.) Mill hydroglycolic extract, as well as evaluate its preliminary and accelerated thermal stability and moisturizing efficacy. The formulations containing 0.5% of xanthan gum (FX) and 0.5% of xanthan gum and 1% of Opuntia ficus-indica MILL extract (FXE) were white, homogeneus and fluid in aspect. Both formulations were stable during preliminary and accelerated stability tests. FX and FXE presented a pH compatible to skin pH (4.5-6.0); droplet size varying from 92.2 to 233.6 nm; a polydispersion index (PDI) around 0.200 and a zeta potential from -26.71 to -47.01 mV. FXE was able to increase the water content of the stratum corneum for 5 h after application on the forearm. The O/W nanoemulsions containing 1% of Opuntia ficus-indica (L.) Mill extract presented suitable stability for at least for 60 days. Besides, this formulation was able to increase the water content of stratum corneum, showing its moisturizing efficacy.

Hydrogen storage thermodynamics and kinetics of LaMg11Ni + x wt.% Ni (x = 100, 200) alloys synthesized by mechanical milling

International Nuclear Information System (INIS)

Zhang, Yanghuan; Jia, Zhichao; Central Iron and Steel Research Institute, Beijing; Yuan, Zeming; Qi, Yan; Zhao, Dongliang; Hou, Zhonghui

2016-01-01

LaMg 11 Ni + x wt.% Ni (x = 100, 200) composite hydrogen storage alloys with a nanocrystalline/amorphous structure were synthesized using ball milling technology. The effects of Ni content and milling time on hydrogen storage thermodynamics and dynamics of the alloys were investigated systematically. The hydrogen desorption properties were assessed using a Sieverts apparatus and differential scanning calorimetry. The thermodynamic parameters for the hydrogen absorption and desorption were calculated using the Van't Hoff equation. The hydrogen desorption activation energies of the hydrogenated alloys were also estimated by Arrhenius and Kissinger methods. Results indicate that the amount of Ni added has no effect on the thermodynamics of the alloys, but it significantly improves their absorption and desorption kinetics. Furthermore, the milling time has a great influence on the hydrogen storage properties. To be specific, the hydrogen absorption capacities reach the maximum values with the variation of milling time, and the hydrogen desorption activation energy obviously decreases with increasing milling time.

Magnetic properties of Ni nanoparticles dispersed in silica prepared by high-energy ball milling

Science.gov (United States)

González, E. M.; Montero, M. I.; Cebollada, F.; de Julián, C.; Vicent, J. L.; González, J. M.

1998-04-01

We analyze the magnetic properties of mechanically ground nanosized Ni particles dispersed in a SiO2 matrix. Our magnetic characterization of the as-milled samples show the occurrence of two blocking processes and that of non-monotonic milling time evolutions of the magnetic-order temperature, the high-field magnetization and the saturation coercivity. The measured coercivities exhibit giant values and a uniaxial-type temperature dependence. Thermal treatment carried out in the as-prepared samples result in a remarkable coercivity reduction and in an increase of the high-field magnetization. We conclude, on the basis of the consideration of a core (pure Ni) and shell (Ni-Si inhomogeneous alloy) particle structure, that the magnetoelastic anisotropy plays the dominant role in determining the magnetic properties of our particles.

Learning Activity Packets for Milling Machines. Unit I--Introduction to Milling Machines.

Science.gov (United States)

Oklahoma State Board of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

This learning activity packet (LAP) outlines the study activities and performance tasks covered in a related curriculum guide on milling machines. The course of study in this LAP is intended to help students learn to identify parts and attachments of vertical and horizontal milling machines, identify work-holding devices, state safety rules, and…

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

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...... dynamics simulations have largely been overlooked in the wave energy sector. In this article, we apply formal verification and validation techniques to computational fluid dynamics simulations of a passively controlled point absorber. The phase control causes the motion response to be highly nonlinear even...

17th Business Report Meeting of New Energy Industrial Technology Development Organization (NEDO). Section Meeting on International Cooperation Projects; Dai 17 kai jigyo hokokukai. Kokusai kyoryoku jigyo bunkakai

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-09-01

In this section meeting, reports were made on the following themes: 1) pregrinder model project; 2) power recovery model project; 3) energy conservation model project and the importance of the spread. In 1), this model project aims to demonstrate that the electric power unit requirement for cement production can be reduced by installing a pregrinder at the front step of ball mill as the finish process at a cement factory in Indonesia, increasing capacity of ball mill grinding, and reducing operational loads of the ball mill which is large in power consumption. In 2), this project aims to supply China a technology to recover power from high temperature/high pressure exhaust gas via gas expander as electric power of 5.8MW after separating FCC catalyst associated with from the exhaust gas from the generative tower of fluid catalytic cracking equipment for oil refining. To come up to expectations for Japan from neighboring countries in Asia, NEDO Information Center carried out the energy conservation model project, etc. as the international cooperation related project in the energy/environment field. The center is now developing 10 projects. (NEDO)

Moessbauer spectroscopy study of the synthesis of SnFe2O4 by high energy ball milling (HEBM) of SnO and α-Fe2O3

International Nuclear Information System (INIS)

Uwakweh, Oswald N C; Perez Moyet, Richard; Mas, Rita; Morales, Carolyn; Vargas, Pedro; Silva, Josue; Rossa, Angel; Lopez, Neshma

2010-01-01

The formation of single phase nanoparticles of spinel structured ferrite, SnFe 2 O 4 , by mechanochemical syntheses using HEBM of stoichiometric amounts of solid SnO and α-Fe 2 O 3 with acetone as surfactant was achieved progressively as function of ball milling time. Single phase SnFe 2 O 4 formation commenced from five hours of continuous ball milling, and reached completion after 22 hours, thereby yielding a material with a lattice parameter of 8.543 A, and particle size of 10.91 nm. The coercivity was 4.44 mT, magnetic saturation value of 17.75 Am 2 /kg, and remanent magnetizations of 1.50 Am 2 /kg, correspondingly. The nanosized particles exhibited superparamagnetic behavior phenomenon based on Moessbauer spectroscopy measurements. The kinetic analyses based on the modified Kissinger method yielded four characteristic stages during the thermal evolution of the 22 hours milled state with activation energies of 0.23 kJ/mol, 2.52 kJ/mol, 0.024 kJ/mol, and 1.57 kJ/mol respectively.

Evaluation of full-strength paper mill effluent for electricity generation ...

African Journals Online (AJOL)

In the search for renewable, sustainable and affordable energy sources, microbial fuel cells (MFCs) offer the advantage of a biological oxidation of pollutants to the direct generation of electricity by microorganisms. We thus examined the biodegradability and suitability of unamended paper mill effluent for power production ...

Singular Minkowski and Euclidean solutions for SU(2) Yang-Mills theory

International Nuclear Information System (INIS)

Singleton, D.

1996-01-01

In this paper it is examined a solution to the SU(2) Yang-Mills-Higgs system, which is a trivial mathematical extension of recently discovered Schwarzschild- like solutions (Singleton D., Phys. Rev. D, 51 (1955) 5911). Physically, however, this new solution has drastically different properties from the Schwarzschild-like solutions. It is also studied a new classical solution for Euclidean SU(2) Yang-Mills theory. Again this new solution is a mathematically trivial extension of the Belavin-Polyakov-Schwartz-Tyupkin (BPST) (Belavin A. A. et al., Phys. Lett. B, 59 (1975) 85) instanton, but is physically very different. Unlike the usual instanton solution, the present solution is singular on a sphere of arbitrary radius in Euclidean space. Both of these solutions are infinite-energy solutions, so their practical value is somewhat unclear. However, they may be useful in exploring some of the mathematical aspects of classical Yang-Mills theory

Variables affecting energy efficiency and CO2 emissions in the steel industry

International Nuclear Information System (INIS)

Siitonen, Sari; Tuomaala, Mari; Ahtila, Pekka

2010-01-01

Specific energy consumption (SEC) is an energy efficiency indicator widely used in industry for measuring the energy efficiency of different processes. In this paper, the development of energy efficiency and CO 2 emissions of steelmaking is studied by analysing the energy data from a case mill. First, the specific energy consumption figures were calculated using different system boundaries, such as the process level, mill level and mill site level. Then, an energy efficiency index was developed to evaluate the development of the energy efficiency at the mill site. The effects of different production conditions on specific energy consumption and specific CO 2 emissions were studied by PLS analysis. As theory expects, the production rate of crude steel and the utilisation of recycled steel were shown to affect the development of energy efficiency at the mill site. This study shows that clearly defined system boundaries help to clarify the role of on-site energy conversion and make a difference between the final energy consumption and primary energy consumption of an industrial plant with its own energy production.

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.

The Influence of Milling and Spark Plasma Sintering on the Microstructure and Properties of the Al7075 Alloy

Science.gov (United States)

Málek, Přemysl; Minárik, Peter; Novák, Pavel; Průša, Filip

2018-01-01

The compact samples of an Al7075 alloy were prepared by a combination of gas atomization, high energy milling, and spark plasma sintering. The predominantly cellular morphology observed in gas atomized powder particles was completely changed by mechanical milling. The continuous-like intermetallic phases present along intercellular boundaries were destroyed; nevertheless, a small amount of Mg(Zn,Cu,Al)2 phase was observed also in the milled powder. Milling resulted in a severe plastic deformation of the material and led to a reduction of grain size from several µm into the nanocrystalline region. The combination of these microstructural characteristics resulted in abnormally high microhardness values exceeding 300 HV. Consolidation through spark plasma sintering (SPS) resulted in bulk samples with negligible porosity. The heat exposition during SPS led to precipitation of intermetallic phases from the non-equilibrium microstructure of both gas atomized and milled powders. SPS of the milled powder resulted in a recrystallization of the severely deformed structure. An ultra-fine grained structure (grain size close to 500 nm) with grains divided primarily by high-angle boundaries was formed. A simultaneous release of stored deformation energy and an increase in the grain size caused a drop of microhardness to values close to 150 HV. This value was retained even after annealing at 425 °C. PMID:29614046

The Influence of Milling and Spark Plasma Sintering on the Microstructure and Properties of the Al7075 Alloy

Directory of Open Access Journals (Sweden)

Orsolya Molnárová

2018-04-01

Full Text Available The compact samples of an Al7075 alloy were prepared by a combination of gas atomization, high energy milling, and spark plasma sintering. The predominantly cellular morphology observed in gas atomized powder particles was completely changed by mechanical milling. The continuous-like intermetallic phases present along intercellular boundaries were destroyed; nevertheless, a small amount of Mg(Zn,Cu,Al2 phase was observed also in the milled powder. Milling resulted in a severe plastic deformation of the material and led to a reduction of grain size from several µm into the nanocrystalline region. The combination of these microstructural characteristics resulted in abnormally high microhardness values exceeding 300 HV. Consolidation through spark plasma sintering (SPS resulted in bulk samples with negligible porosity. The heat exposition during SPS led to precipitation of intermetallic phases from the non-equilibrium microstructure of both gas atomized and milled powders. SPS of the milled powder resulted in a recrystallization of the severely deformed structure. An ultra-fine grained structure (grain size close to 500 nm with grains divided primarily by high-angle boundaries was formed. A simultaneous release of stored deformation energy and an increase in the grain size caused a drop of microhardness to values close to 150 HV. This value was retained even after annealing at 425 °C.

Phase evolution during early stages of mechanical alloying of Cu–13 wt.% Al powder mixtures in a high-energy ball mill

International Nuclear Information System (INIS)

Dudina, Dina V.; Lomovsky, Oleg I.; Valeev, Konstantin R.; Tikhov, Serguey F.; Boldyreva, Natalya N.; Salanov, Aleksey N.; Cherepanova, Svetlana V.; Zaikovskii, Vladimir I.; Andreev, Andrey S.; Lapina, Olga B.; Sadykov, Vladislav A.

2015-01-01

Highlights: • Phase formation during early stages of Cu–Al mechanical alloying was studied. • The products of mechanical alloying are of highly non-equilibrium character. • X-ray amorphous phases are present in the products of mechanical alloying. • An Al-rich X-ray amorphous phase is distributed between the crystallites. - Abstract: We report the phase and microstructure evolution of the Cu–13 wt.% Al mixture during treatment in a high-energy planetary ball mill with a particular focus on the early stages of mechanical alloying. Several characterization techniques, including X-ray diffraction phase analysis, nuclear magnetic resonance spectroscopy, differential dissolution, thermal analysis, and electron microscopy/elemental analysis, have been combined to study the evolution of the phase composition of the mechanically alloyed powders and describe the microstructure of the multi-phase products of mechanical alloying at different length scales. The following reaction sequence has been confirmed: Cu + Al → CuAl 2 (+Cu) → Cu 9 Al 4 + (Cu) → Cu(Al). The phase evolution was accompanied by the microstructure changes, the layered structure of the powder agglomerates disappearing with milling time. This scheme is further complicated by the processes of copper oxidation, reduction of copper oxides by metallic aluminum, and by variation of the stoichiometry of Cu(Al) solid solutions with milling time. Substantial amounts of X-ray amorphous phases were detected as well. Differential dissolution technique has revealed that a high content of aluminum in the Cu(Al) solid solution-based powders is due to the presence of Al-rich phases distributed between the Cu(Al) crystallites

The progress in the researches for uranium mill tailings cleaning treatment and no-waste uranium ore milling processes

International Nuclear Information System (INIS)

Wang Jintang

1990-01-01

The production of uranium mill tailings and their risk assessment are described. The moethods of uranium mill tailings disposal and management are criticized and the necessity of the researches for uranium mill tailings cleaning treatment and no-wasle uranium ore milling process are demonstrated. The progress for these researches in China and other countries with uranium production is reviewed, and the corresponding conclusions are reported

75 FR 49524 - Woodland Mills Corporation, Mill Spring, NC; Notice of Affirmative Determination Regarding...

Science.gov (United States)

2010-08-13

... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-73,695] Woodland Mills Corporation, Mill Spring, NC; Notice of Affirmative Determination Regarding Application for Reconsideration By application dated July 22, 2010, petitioners requested administrative [[Page 49525

Superfine powdered activated carbon (S-PAC) coatings on microfiltration membranes: Effects of milling time on contaminant removal and flux.

Science.gov (United States)

Amaral, Pauline; Partlan, Erin; Li, Mengfei; Lapolli, Flavio; Mefford, O Thompson; Karanfil, Tanju; Ladner, David A

2016-09-01

In microfiltration processes for drinking water treatment, one method of removing trace contaminants is to add powdered activated carbon (PAC). Recently, a version of PAC called superfine PAC (S-PAC) has been under development. S-PAC has a smaller particle size and thus faster adsorption kinetics than conventionally sized PAC. Membrane coating performance of various S-PAC samples was evaluated by measuring adsorption of atrazine, a model micropollutant. S-PACs were created in-house from PACs of three different materials: coal, wood, and coconut shell. Milling time was varied to produce S-PACs pulverized with different amounts of energy. These had different particles sizes, but other properties (e.g. oxygen content), also differed. In pure water the coal based S-PACs showed superior atrazine adsorption; all milled carbons had over 90% removal while the PAC had only 45% removal. With addition of calcium and/or NOM, removal rates decreased, but milled carbons still removed more atrazine than PAC. Oxygen content and specific external surface area (both of which increased with longer milling times) were the most significant predictors of atrazine removal. S-PAC coatings resulted in loss of filtration flux compared to an uncoated membrane and smaller particles caused more flux decline than larger particles; however, the data suggest that NOM fouling is still more of a concern than S-PAC fouling. The addition of calcium improved the flux, especially for the longer-milled carbons. Overall the data show that when milling S-PAC with different levels of energy there is a tradeoff: smaller particles adsorb contaminants better, but cause greater flux decline. Fortunately, an acceptable balance may be possible; for example, in these experiments the coal-based S-PAC after 30 min of milling achieved a fairly high atrazine removal (overall 80%) with a fairly low flux reduction (under 30%) even in the presence of NOM. This suggests that relatively short duration (low energy

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.)

SO(4)-symmetric solutions of Minkowskian Yang-Mills field equations

International Nuclear Information System (INIS)

Luescher, M.

1977-06-01

We construct all solutions to the SU(2) Yang-Mills field equations in Minkowski space that are invariant under an SO(4) subgroup of the conformal group. They are real, regular and have finite energy and action. A connection with the instanton solution is pointed out. (orig.) [de

An energy stable algorithm for a quasi-incompressible hydrodynamic phase-field model of viscous fluid mixtures with variable densities and viscosities

Science.gov (United States)

Gong, Yuezheng; Zhao, Jia; Wang, Qi

2017-10-01

A quasi-incompressible hydrodynamic phase field model for flows of fluid mixtures of two incompressible viscous fluids of distinct densities and viscosities is derived by using the generalized Onsager principle, which warrants the variational structure, the mass conservation and energy dissipation law. We recast the model in an equivalent form and discretize the equivalent system in space firstly to arrive at a time-dependent ordinary differential and algebraic equation (DAE) system, which preserves the mass conservation and energy dissipation law at the semi-discrete level. Then, we develop a temporal discretization scheme for the DAE system, where the mass conservation and the energy dissipation law are once again preserved at the fully discretized level. We prove that the fully discretized algorithm is unconditionally energy stable. Several numerical examples, including drop dynamics of viscous fluid drops immersed in another viscous fluid matrix and mixing dynamics of binary polymeric solutions, are presented to show the convergence property as well as the accuracy and efficiency of the new scheme.

Black holes with Yang-Mills hair

International Nuclear Information System (INIS)

Kleihaus, B.; Kunz, J.; Sood, A.; Wirschins, M.

1998-01-01

In Einstein-Maxwell theory black holes are uniquely determined by their mass, their charge and their angular momentum. This is no longer true in Einstein-Yang-Mills theory. We discuss sequences of neutral and charged SU(N) Einstein-Yang-Mills black holes, which are static spherically symmetric and asymptotically flat, and which carry Yang-Mills hair. Furthermore, in Einstein-Maxwell theory static black holes are spherically symmetric. We demonstrate that, in contrast, SU(2) Einstein-Yang-Mills theory possesses a sequence of black holes, which are static and only axially symmetric

Study of the structural and magnetic properties of metallic iron-hematite particles for use in magnetorheological fluids

Energy Technology Data Exchange (ETDEWEB)

Osorio Ospina, Diana Marcela; Castro Navas, Irvin Jadway [Universidad del Valle, Escuela de Ingenieria de Materiales (Colombia); Perez Alcazar, German Antonio; Tabares, Jesus Anselmo, E-mail: jesus_tabares_8@hotmail.com [Universidad del Valle, Departamento de Fisica (Colombia)

2012-03-15

Magnetorheological (MR) fluids are new iron-based materials, whose applications include brakes, dampers, clutches, shock absorbers systems and polishing of optical surfaces (lens and mirrors). They are dependent on the size and shape of particles as the magnetic properties. Interested in the possibility of using iron-rich powders, commonly used in nondestructive testing, ranging in size from a few {mu}m to about 200 {mu}m and lower cost than those commercially used for MR fluids, a study of the structural and magnetic properties of iron-rich metallic particles by X-ray diffraction (XRD) and Moessbauer spectroscopy (MS) at room temperature has been done. Powders, as received, were separated into particle sizes smaller than 20 {mu}m (sample A) and in the range of 20-38 {mu}m (sample B) because these are the sizes generally required for applications in MR fluids. The particles whose sizes exceed the above values were ground in a high energy planetary mill for 3 h, using different values of rotational speed/time: 200 rpm for one hour, a pause of 10 s, 140 rpm for one hour, pause 10 s and then 175 rpm during the last hour. These powders were sieved to obtain particles smaller than 20 {mu}m (sample C). According XRD results, in all samples, only {alpha}-Fe (lattice parameter a = 2,867(2) Angstrom-Sign ) and Fe{sub 2}O{sub 3} (lattice parameter a 5,037(1) Angstrom-Sign and c = 13,755(8) Angstrom-Sign ) were present. The Moessbauer spectra were fitted with two sextets. The hyperfine parameters values allowed us to assign the highest relative area spectrum (sextet) corresponding to {alpha}-Fe and the second one to Fe{sub 2}O{sub 3} in accord to the XRD results. Thus, the preparation method using mechanical milling for diminishing the size of the metallic particles allowed us to get particles with size and magnetic properties that could lead to potentially MR fluids applications.

Study of the structural and magnetic properties of metallic iron-hematite particles for use in magnetorheological fluids

International Nuclear Information System (INIS)

Osorio Ospina, Diana Marcela; Castro Navas, Irvin Jadway; Pérez Alcázar, German Antonio; Tabares, Jesus Anselmo

2012-01-01

Magnetorheological (MR) fluids are new iron-based materials, whose applications include brakes, dampers, clutches, shock absorbers systems and polishing of optical surfaces (lens and mirrors). They are dependent on the size and shape of particles as the magnetic properties. Interested in the possibility of using iron-rich powders, commonly used in nondestructive testing, ranging in size from a few μm to about 200 μm and lower cost than those commercially used for MR fluids, a study of the structural and magnetic properties of iron-rich metallic particles by X-ray diffraction (XRD) and Mössbauer spectroscopy (MS) at room temperature has been done. Powders, as received, were separated into particle sizes smaller than 20 μm (sample A) and in the range of 20–38 μm (sample B) because these are the sizes generally required for applications in MR fluids. The particles whose sizes exceed the above values were ground in a high energy planetary mill for 3 h, using different values of rotational speed/time: 200 rpm for one hour, a pause of 10 s, 140 rpm for one hour, pause 10 s and then 175 rpm during the last hour. These powders were sieved to obtain particles smaller than 20 μm (sample C). According XRD results, in all samples, only α-Fe (lattice parameter a = 2,867(2) Å) and Fe 2 O 3 (lattice parameter a 5,037(1) Å and c = 13,755(8) Å) were present. The Mössbauer spectra were fitted with two sextets. The hyperfine parameters values allowed us to assign the highest relative area spectrum (sextet) corresponding to α-Fe and the second one to Fe 2 O 3 in accord to the XRD results. Thus, the preparation method using mechanical milling for diminishing the size of the metallic particles allowed us to get particles with size and magnetic properties that could lead to potentially MR fluids applications.

Colorado's prospectus on uranium milling

International Nuclear Information System (INIS)

Hazle, A.J.; Franz, G.A.; Gamewell, R.

1982-01-01

The first part of this paper will discuss Colorado's control of uranium mill tailings under Titles I and II of the Uranium Mill Tailings Radiation Control Act of 1978. Colorado has a legacy of nine inactive mill sites requiring reclamation under Title I, and two presently active plus a number of new mill proposals which must be regulated in accordance with Title II. Past failures in siting and control on the part of federal jurisdictions have left the state with a heavy legacy requiring extensive effort to address impacts to the state's environment and population. The second part of this paper will discuss the remedial action programme authorized under Public Law 92-314 for Mesa Country, where lack of federal control led to the dispersal of several hundred thousand tons of uranium mill tailings on thousands of properties, including hundreds of homes, schools and other structures. Successful completion of the State efforts under both programmes will depend on a high level of funding and on the maintenance of adequate regulatory standards. (author)

Understanding dental CAD/CAM for restorations - dental milling machines from a mechanical engineering viewpoint. Part A: chairside milling machines.

Science.gov (United States)

Lebon, Nicolas; Tapie, Laurent; Duret, Francois; Attal, Jean-Pierre

2016-01-01

The dental milling machine is an important device in the dental CAD/CAM chain. Nowadays, dental numerical controlled (NC) milling machines are available for dental surgeries (chairside solution). This article provides a mechanical engineering approach to NC milling machines to help dentists understand the involvement of technology in digital dentistry practice. First, some technical concepts and definitions associated with NC milling machines are described from a mechanical engineering viewpoint. The technical and economic criteria of four chairside dental NC milling machines that are available on the market are then described. The technical criteria are focused on the capacities of the embedded technologies of these milling machines to mill both prosthetic materials and types of shape restorations. The economic criteria are focused on investment costs and interoperability with third-party software. The clinical relevance of the technology is assessed in terms of the accuracy and integrity of the restoration.

Microstructural characteristics and mechanical properties of carbon nanotube reinforced aluminum alloy composites produced by ball milling

International Nuclear Information System (INIS)

Raviathul Basariya, M.; Srivastava, V.C.; Mukhopadhyay, N.K.

2014-01-01

Highlights: • 6082 Al alloy composite with 2 wt% multiwalled carbon nanotubes prepared by milling. • Effect of milling time on structure and property evolution has been studied. • The reinforced composite powders showed a drastic crystallite size refinement. • The presence of carbon nanotube led to a two fold increase in the hardness and modulus. • The composite powder showed good thermal stability studied by DTA. - Abstract: The influence of milling time on the structure, morphology and thermal stability of multi-walled carbon nanotubes (MWCNTs) reinforced EN AW6082 aluminum alloy powders has been studied. After structural and microstructural characterization of the mechanically milled powders micro- and nano-hardness of the composite powder particles were evaluated. The morphological and X-ray diffraction studies on the milled powders revealed that the carbon nanotubes (CNTs) were uniformly distributed and embedded within the aluminum matrix. No reaction products were detected even after long milling up to 50 h. Nanotubes became shorter in length as they fractured under the impact and shearing action during the milling process. A high hardness of about 436 ± 52 HV is achieved for the milled powders, due to the addition of MWCNTs, after milling for 50 h. The increased elastic modulus and nanohardness can be attributed to the finer grain size evolved during high energy ball milling and to the uniform distribution of hard CNTs in the Al-alloy matrix. The hardness values of the composite as well as the matrix alloy compares well with that predicted by the Hall–Petch relationship

Dependence of hydrogen storage characteristics of mechanically milled carbon materials on their host structures

International Nuclear Information System (INIS)

Shindo, K.; Kondo, T.; Sakurai, Y.

2004-01-01

We investigated whether the hydrogen storage characteristics of carbon materials prepared by mechanical milling in an H 2 atmosphere were dependent on their host structures. We used natural graphite (NG) and activated carbon fibers (ACF) and compared them with activated carbon (AC) powders. The XRD patterns of NG and ACF milled for over 20 h and SEM images of these samples milled for 80 h were almost the same as those of AC. The hydrogen storage capacities of NG and ACF estimated by the inert gas fusion-thermal conductivity method increased with the mechanical milling time up to 10 h and showed little milling time dependence thereafter. The capacities of NG and ACF reached about 3.0 wt.% and were similar to that of AC. However, it should be noted that the hydrogen storage mechanism of NG and ACF mechanically milled in an H 2 atmosphere might be different because the changes in their specific surface areas with milling time were opposite. Thermal desorption mass spectroscopy (TDS) revealed that the desorption spectra of the hydrogen molecules (mass number=2) of NG and ACF milled for 10 h in the same way as AC contained two peaks at about 500 and 800 deg. C. The desorption activation energies of hydrogenated NG and ACF at these peaks calculated from a Kissinger plot were almost with the same as those of hydrogenated AC. This suggests that the state of the hydrogen trapped in the structural defects in NG introduced by the mechanical milling may be almost the same as that of AC. In addition, we assumed the possibility that the state of the hydrogen in ACF hydrogenated by mechanical milling could be almost the same as that in hydrogenated AC. We considered that the nanocarbon materials hydrogenated under our milling conditions had very similar physical shapes and hydrogen storage capacities, independent of their host structures

John Stuart Mill: utilitarismo e liberalismo = John Stuart Mill: utilitarianism and liberalism

Directory of Open Access Journals (Sweden)

Simões, Mauro Cardoso

2013-01-01

Full Text Available Meu objetivo, neste trabalho, é investigar a compatibilidade das teses utilitaristas e liberais de John Stuart Mill. Apresentarei, inicialmente, os principais críticos da filosofia moral e política de Mill, para os quais o discípulo de Bentham teria abandonado o utilitarismo ou, ainda, não esclarecido suficientemente seu princípio da liberdade, o que o tornaria um pensador assistemático e inconsistente. Minha tese é contrária a tais interpretações, uma vez que sustenta ser Mill consistente. Em seguida, defenderei uma interpretação do princípio da liberdade e da individualidade, procurando demonstrar que seu utilitarismo é compatível com seu liberalismo

Annual status report on the Uranium Mill Tailings Remedial Action Program

International Nuclear Information System (INIS)

1992-12-01

This fourteenth annual status report for the Uranium Mill Tailings Remedial Action (UMTRA) Project Office summarizes activities of the Uranium Mill Tailings Remedial Action Surface (UMTRA-Surface) and Uranium Mill Tailings Remedial Action Groundwater (UMTRA-Groundwater) Projects undertaken during fiscal year (FY) 1992 by the US Department of Energy (DOE) and other agencies. Project goals for FY 1993 are also presented. An annual report of this type was a statutory requirement through January 1, 1986, pursuant to the Uranium Mill Tailings Radiation Control Act (UMTRCA) of 1978, Public Law (PL) 95-604. The DOE will continue to submit annual reports to DOE-Headquarters, the states, tribes, and local representatives through Project completion in order to inform the public of the yearly Project status. The purpose of the remedial action is to stabilize and control the tailings and other residual radioactive material (RRM) located on the inactive uranium processing sites in a safe and environmentally sound manner, and to minimize or eliminate potential health hazards. Commercial and residential properties near designated processing sites that are contaminated with material from the sites, herein referred to as ''vicinity properties (VP),'' are also eligible for remedial action. Included in the UMTRA Project are 24 inactive uranium processing sites and associated VPs located in 10 states, and the VPs associated with the Edgemont, South Dakota, uranium mill currently owned by the Tennessee Valley Authority (TVA) (Figure A.1, Appendix A)

Optimization of FIB milling for rapid NEMS prototyping

DEFF Research Database (Denmark)

Malm, Bjarke; Petersen, Dirch Hjorth; Lei, Anders

2011-01-01

We demonstrate an optimized milling technique to focused ion beam (FIB) milling in template silicon membranes for fast prototyping of nanoelectromechanical systems (NEMS). Using a single-pass milling strategy the highly topology dependent sputtering rate is boosted and shorter milling time...... is achieved. Drift independence is obtained for small critical features using a radial scan strategy, and a back scan routine ensures minimal line width deviation removing redeposited material. Milling a design similar to a nano four-point probe with a pitch down to 400nm we display what optimized FIB milling...

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.

Yang-Mills theory for non-semisimple groups

CERN Document Server

Nuyts, J; Nuyts, Jean; Wu, Tai Tsun

2003-01-01

For semisimple groups, possibly multiplied by U(1)'s, the number of Yang-Mills gauge fields is equal to the number of generators of the group. In this paper, it is shown that, for non-semisimple groups, the number of Yang-Mills fields can be larger. These additional Yang-Mills fields are not irrelevant because they appear in the gauge transformations of the original Yang-Mills fields. Such non-semisimple Yang-Mills theories may lead to physical consequences worth studying. The non-semisimple group with only two generators that do not commute is studied in detail.

Chevron's Panna Maria mill process description

International Nuclear Information System (INIS)

Anon.

1979-01-01

Key features of Chevron's Uranium Mill located near Panna Maria, Texas, are described. The mill is designed to process a nominal 2500 dry tons/day of uranium bearing ore containing 15% uncombined moisture. The following operations at the mill are highlighted: ore receiving, grinding, leaching, countercurrent decantation and tailings disposal, filtering, solvent extraction, solvent stripping, precipitation, drying, and packaging

The magnetic properties of mill scale-derived permanent magnet

International Nuclear Information System (INIS)

Woon, H.S.; Hashim, M.M.; Yahya, N.; Zakaria, A.; Lim, K.P.

2005-01-01

In the permanent magnet SrO-FeO-Fe 2 O 3 system, there exist several magnetically ordered compounds with a stable phase at room temperature. The most important are the M(SrFe 12 O 19 ), X(SrFe 15 O 23 ) and W(SrFe 18 O 27 ) phases with hexagonal close packed structure. In this project, M(SrFe 12 O 19 ) was prepared using mill scale, a steel-maker byproduct, as raw material. The Malaysia steel industry generates approximately 30,000 metric tons of waste products such as mill scale every year. Transportation and disposal of the byproducts are costly and the environmental regulations are becoming stricter. Hence, local steel mills are to find new ways to recycle the waste as a feedstock for the steel-making process or as a saleable product. The M(SrFe 12 O 19 ) was synthesized using the conventional ceramic process. The formation of the SrFe 12 O 19 was confirmed by X-ray diffraction. The magnetic properties such as the energy product (BH)max, coercive force (iHc) and remanence (Br) were also reported in this paper. (Author)

Architecture and environmental restoration: Remediating uranium mill tailings from buildings

International Nuclear Information System (INIS)

Teply, J.D.

1991-01-01

The US Department of Energy (DOE) Grand Junction Projects Office (GJPO) manages the Uranium Mill Tailings Remedial Action (UMTRA) Program in Grand Junction, Colorado. This program is a congressionally mandated clean up of by-product waste that resulted from the extraction of yellow cake from uranium ore. The by-product waste, a fine sand commonly called open-quotes mill tailingclose quotes is contaminated with low-level radioactivity. These mill tailings were available to the community for use as construction material from approximately 1952 to 1966; their use as bedding material for concrete slabs, utilities, backfill materials, concrete sand, and mortar created unique remediation problems that required innovative solutions. This paper describes how design personnel approach the remediation of structures, the evaluation of the buildings, and the factors that must be considered in completing the remediation design. This paper will not address the health risks of the tailings in an inhabited space, the remediation of exterior areas, or the process of determining where the tailings exist in the building

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

Effectiveness and resolution of tests for evaluating the performance of cutting fluids in machining aerospace alloys

DEFF Research Database (Denmark)

De Chiffre, Leonardo; Axinte, Dragos A.

2008-01-01

The paper discusses effectiveness and resolution of five cutting tests (turning, milling, drilling, tapping, VIPER grinding) and their quality output measures used in a multi-task procedure for evaluating the performance of cutting fluids when machining aerospace materials. The evaluation takes...

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

Noncommutative geometry and fluid dynamics

International Nuclear Information System (INIS)

Das, Praloy; Ghosh, Subir

2016-01-01

In the present paper we have developed a Non-Commutative (NC) generalization of perfect fluid model from first principles, in a Hamiltonian framework. The noncommutativity is introduced at the Lagrangian (particle) coordinate space brackets and the induced NC fluid bracket algebra for the Eulerian (fluid) field variables is derived. Together with a Hamiltonian this NC algebra generates the generalized fluid dynamics that satisfies exact local conservation laws for mass and energy, thereby maintaining mass and energy conservation. However, nontrivial NC correction terms appear in the charge and energy fluxes. Other non-relativistic spacetime symmetries of the NC fluid are also discussed in detail. This constitutes the study of kinematics and dynamics of NC fluid. In the second part we construct an extension of the Friedmann-Robertson-Walker (FRW) cosmological model based on the NC fluid dynamics presented here. We outline the way in which NC effects generate cosmological perturbations bringing about anisotropy and inhomogeneity in the model. We also derive a NC extended Friedmann equation. (orig.)

Noncommutative geometry and fluid dynamics

Energy Technology Data Exchange (ETDEWEB)

Das, Praloy; Ghosh, Subir [Indian Statistical Institute, Physics and Applied Mathematics Unit, Kolkata (India)

2016-11-15

In the present paper we have developed a Non-Commutative (NC) generalization of perfect fluid model from first principles, in a Hamiltonian framework. The noncommutativity is introduced at the Lagrangian (particle) coordinate space brackets and the induced NC fluid bracket algebra for the Eulerian (fluid) field variables is derived. Together with a Hamiltonian this NC algebra generates the generalized fluid dynamics that satisfies exact local conservation laws for mass and energy, thereby maintaining mass and energy conservation. However, nontrivial NC correction terms appear in the charge and energy fluxes. Other non-relativistic spacetime symmetries of the NC fluid are also discussed in detail. This constitutes the study of kinematics and dynamics of NC fluid. In the second part we construct an extension of the Friedmann-Robertson-Walker (FRW) cosmological model based on the NC fluid dynamics presented here. We outline the way in which NC effects generate cosmological perturbations bringing about anisotropy and inhomogeneity in the model. We also derive a NC extended Friedmann equation. (orig.)

Galilean Yang-Mills theory

Energy Technology Data Exchange (ETDEWEB)

Bagchi, Arjun [Center for Theoretical Physics, Massachusetts Institute of Technology,77 Massachusetts Avenue, Cambridge, MA 02139 (United States); Basu, Rudranil [Saha Institute of Nuclear Physics,Block AF, Sector 1, Bidhannagar, Kolkata 700068 (India); Kakkar, Ashish [Indian Institute of Science Education and Research,Dr Homi Bhabha Road, Pashan. Pune 411008 (India); Mehra, Aditya [Indian Institute of Science Education and Research,Dr Homi Bhabha Road, Pashan. Pune 411008 (India); Van Swinderen Institute for Particle Physics and Gravity, University of Groningen, Nijenborgh 4, 9747 AG Groningen (Netherlands)

2016-04-11

We investigate the symmetry structure of the non-relativistic limit of Yang-Mills theories. Generalising previous results in the Galilean limit of electrodynamics, we discover that for Yang-Mills theories there are a variety of limits inside the Galilean regime. We first explicitly work with the SU(2) theory and then generalise to SU(N) for all N, systematising our notation and analysis. We discover that the whole family of limits lead to different sectors of Galilean Yang-Mills theories and the equations of motion in each sector exhibit hitherto undiscovered infinite dimensional symmetries, viz. infinite Galilean Conformal symmetries in D=4. These provide the first examples of interacting Galilean Conformal Field Theories (GCFTs) in D>2.

Galilean Yang-Mills theory

International Nuclear Information System (INIS)

Bagchi, Arjun; Basu, Rudranil; Kakkar, Ashish; Mehra, Aditya

2016-01-01

We investigate the symmetry structure of the non-relativistic limit of Yang-Mills theories. Generalising previous results in the Galilean limit of electrodynamics, we discover that for Yang-Mills theories there are a variety of limits inside the Galilean regime. We first explicitly work with the SU(2) theory and then generalise to SU(N) for all N, systematising our notation and analysis. We discover that the whole family of limits lead to different sectors of Galilean Yang-Mills theories and the equations of motion in each sector exhibit hitherto undiscovered infinite dimensional symmetries, viz. infinite Galilean Conformal symmetries in D=4. These provide the first examples of interacting Galilean Conformal Field Theories (GCFTs) in D>2.

Texture formation in iron particles using mechanical milling with graphite as a milling aid

Energy Technology Data Exchange (ETDEWEB)

Motozuka, S.; Hayashi, K. [Department of Mechanical Engineering, Gifu National College of Technology, 2236-2 Kamimakuwa, Motosu, Gifu 501-0495 (Japan); Tagaya, M. [Department of Materials Science and Technology, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188 (Japan); Morinaga, M. [Toyota Physical and Chemical Research Institute, 41-1, Yokomichi, Nagakute, Aichi 480-1192 (Japan)

2015-09-15

Crystallographically anisotropic platelet iron particles were successfully prepared using a conventional ball mill with addition of graphite (Gp) particles. The morphological and structural changes resulting from the milling were investigated using scanning electron microscopy and X-ray diffraction. The spherical iron particles were plastically deformed into platelet shapes during the milling. Simultaneously, it is suggested that the size of the Gp particles decreased and adhered as nanoparticles on the surface of the iron particles. The adhered Gp particles affected the plastic deformation behavior of the iron particles: the (001) planes of α-iron were oriented parallel to the particle face, and no preferred in-plane orientation was observed. This study not only details the preparation of soft magnetic metal particles that crystallographically oriented to enhance their magnetic properties but also provides new insight into the activities of the well-established and extensively studied mechanical milling method.

Texture formation in iron particles using mechanical milling with graphite as a milling aid

International Nuclear Information System (INIS)

Motozuka, S.; Hayashi, K.; Tagaya, M.; Morinaga, M.

2015-01-01

Crystallographically anisotropic platelet iron particles were successfully prepared using a conventional ball mill with addition of graphite (Gp) particles. The morphological and structural changes resulting from the milling were investigated using scanning electron microscopy and X-ray diffraction. The spherical iron particles were plastically deformed into platelet shapes during the milling. Simultaneously, it is suggested that the size of the Gp particles decreased and adhered as nanoparticles on the surface of the iron particles. The adhered Gp particles affected the plastic deformation behavior of the iron particles: the (001) planes of α-iron were oriented parallel to the particle face, and no preferred in-plane orientation was observed. This study not only details the preparation of soft magnetic metal particles that crystallographically oriented to enhance their magnetic properties but also provides new insight into the activities of the well-established and extensively studied mechanical milling method

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...

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.

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

Magnetic structure evolution in mechanically milled nanostructured ZnFe2O4 particles

DEFF Research Database (Denmark)

Jiang, Jianzhong; Wynn, P.; Mørup, Steen

1999-01-01

Nanostructured partially-inverted ZnFe2O4 particles have been prepared from bulk ZnFe2O4 by high-energy ball milling in an open container. The grain size reduction, cation site distributions, and the evolution of magnetic structures have been studied by x-ray diffraction with Rietveld structure...... refinements, transmission electron microscopy, and Mossbauer spectroscopy. It is found that a change of magnetic structure from an antiferromagnetic to a ferrimagnetic (or ferromagnetic) structure occurs in the milled samples. This change is correlated with the redistribution of the cations, Zn and Fe...

Atomistic Modeling of the Fluid-Solid Interface in Simple Fluids

Science.gov (United States)

Hadjiconstantinou, Nicolas; Wang, Gerald

2017-11-01

Fluids can exhibit pronounced structuring effects near a solid boundary, typically manifested in a layered structure that has been extensively shown to directly affect transport across the interface. We present and discuss several results from molecular-mechanical modeling and molecular-dynamics (MD) simulations aimed at characterizing the structure of the first fluid layer directly adjacent to the solid. We identify a new dimensionless group - termed the Wall number - which characterizes the degree of fluid layering, by comparing the competing effects of wall-fluid interaction and thermal energy. We find that in the layering regime, several key features of the first layer layer - including its distance from the solid, its width, and its areal density - can be described using mean-field-energy arguments, as well as asymptotic analysis of the Nernst-Planck equation. For dense fluids, the areal density and the width of the first layer can be related to the bulk fluid density using a simple scaling relation. MD simulations show that these results are broadly applicable and robust to the presence of a second confining solid boundary, different choices of wall structure and thermalization, strengths of fluid-solid interaction, and wall geometries.

Control of Natural Zeolite Properties by Mechanical Activation in Stirred Media Mill

Directory of Open Access Journals (Sweden)

Bohács K.

2017-06-01

Full Text Available Due to the special characteristics of zeolites, they can be applied in a very wide range of industries, i.e. agricultural, environmental or water treatment purposes. Generally, high added value zeolite products are manufactured by micro- or nanogrinding. However, these processes require high energy input and cause significant wearing of the mill parts. Therefore, the optimization of zeolite grinding, as well as the control of its properties are of a great importance. In the present paper a Hungarian natural zeolite was mechanically activated in stirred media mill for various residence times in distilled water, meanwhile the particle size distribution and the grinding energy were measured. Additionally, on-line tube rheometer was used to study the rheology of the suspension during the grinding process. The particle interaction and the suspension aggregation stability were detected by zeta-potential measurements. Structural changes due to the mechanical activation process were monitored by FTIR. It was found that the material structure of the zeolite, as well as the rheological behaviour of the zeolite suspension and its aggregation stability had been altered due to the mechanical activation in the stirred media mill. It can be concluded that the zeolite product properties can be modified by mechanical activation in order to produce a high added value tailored material.