Beyond the material grave: Life Cycle Impact Assessment of leaching from secondary materials in road and earth constructions

Energy Technology Data Exchange (ETDEWEB)

Schwab, Oliver [Swiss Federal Institute of Technology Zurich, Institute of Environmental Engineering, John-von-Neumann-Weg 9, 8093 Zurich (Switzerland); Karlsruhe Institute of Technology, Institute for Geography and Geoecology, Adenauerring 20, 76131 Karlsruhe (Germany); Bayer, Peter, E-mail: bayer@erdw.ethz.ch [Swiss Federal Institute of Technology Zurich, Geological Institute, Sonneggstrasse 5, 8092 Zurich (Switzerland); Juraske, Ronnie [Swiss Federal Institute of Technology Zurich, Institute of Environmental Engineering, John-von-Neumann-Weg 9, 8093 Zurich (Switzerland); Verones, Francesca [Swiss Federal Institute of Technology Zurich, Institute of Environmental Engineering, John-von-Neumann-Weg 9, 8093 Zurich (Switzerland); Department of Environmental Science, Institute for Water and Wetland Research, Radboud University Nijmegen, P.O. Box 9010, 6500 GL Nijmegen (Netherlands); Hellweg, Stefanie [Swiss Federal Institute of Technology Zurich, Institute of Environmental Engineering, John-von-Neumann-Weg 9, 8093 Zurich (Switzerland)

2014-10-15

Highlights: • We model environmental impacts of leaching from secondary construction material. • Industrial wastes in construction contain up to 45,000 t heavy metals per year (D). • In a scenario, 150 t are leached to the environment within 100 years after construction. • All heavy metals but As, Sb and Mo are adsorbed by 20 cm subsoil in this scenario. • Environmental impacts depend on material, pollutant, construction type, and geography. - Abstract: In industrialized countries, large amounts of mineral wastes are produced. They are re-used in various ways, particularly in road and earth constructions, substituting primary resources such as gravel. However, they may also contain pollutants, such as heavy metals, which may be leached to the groundwater. The toxic impacts of these emissions are so far often neglected within Life Cycle Assessments (LCA) of products or waste treatment services and thus, potentially large environmental impacts are currently missed. This study aims at closing this gap by assessing the ecotoxic impacts of heavy metal leaching from industrial mineral wastes in road and earth constructions. The flows of metals such as Sb, As, Pb, Cd, Cr, Cu, Mo, Ni, V and Zn originating from three typical constructions to the environment are quantified, their fate in the environment is assessed and potential ecotoxic effects evaluated. For our reference country, Germany, the industrial wastes that are applied as Granular Secondary Construction Material (GSCM) carry more than 45,000 t of diverse heavy metals per year. Depending on the material quality and construction type applied, up to 150 t of heavy metals may leach to the environment within the first 100 years after construction. Heavy metal retardation in subsoil can potentially reduce the fate to groundwater by up to 100%. One major challenge of integrating leaching from constructions into macro-scale LCA frameworks is the high variability in micro-scale technical and geographical factors

Effect of weld metal toughness on fracture behavior under ultra-low cycle fatigue loading (earthquake)

Energy Technology Data Exchange (ETDEWEB)

Kermajani, M. [School of Materials Engineering, College of Engineering, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Ghaini, F. Malek, E-mail: Fmalek@modares.ac.ir [School of Materials Engineering, College of Engineering, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Miresmaeili, R. [School of Materials Engineering, College of Engineering, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Aghakouchak, A.A. [School of Civil Engineering, College of Engineering, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Shadmand, M. [Department of Research and Development, MAPNA Electric and Control (MECO) Company, Karaj (Iran, Islamic Republic of)

2016-06-21

Results from 12 ultra-low cycle fatigue tests performed on the weld metals of both toughness and non-toughness rated grades are presented. Fracture resistance under these loadings seemed to be dependent on materials' toughness, displacement amplitude, and stress state triaxiality, while the toughness effect was more highlighted at high stress levels and concentrations. To study the effect of microstructures on these failures, supporting ancillary tests including all-weld tension coupons, Charpy V-notched impact tests, and optical and scanning electron microscope analyses were performed. The favored microstructures appeared to be those which absorbed energy by plastic deformation and, hence, hindered void formation and/or could avoid crack propagation by deflection. Considering the response of the tested materials to cyclic loadings and the requirements of the materials specified in AISC341 Provisions could question the adequacy of these requirements for weld metals. However, the role of microstructural features like inclusions would be the same in both the Charpy impact tests and ultra-low cycle loadings.

Effects of the exotic zebra mussel (Dreissena polymorpha) on metal cycling in Lake Erie

International Nuclear Information System (INIS)

Klerks, P.L.; Fraleigh, P.C.; Lawniczak, J.E.

1997-01-01

This research demonstrated the impact of high densities of the zebra mussel (Dreissena polymorpha) on the cycling of copper, nickel, and zinc in a lake environment. Experiments with mussels on sedimentation traps in western Lake Erie and with mussels in flow-through tanks receiving Lake Erie water showed that zebra mussels remove metals from the water column, incorporate metals in their tissues, and deposit metals on the lake bottom. Removal of metals from the water column was estimated at 10-17%·day -1 of the amounts present. This material was largely deposited on the lake bottom; zebra mussels more than doubled the rate at which metals were being added to the lake bottom. Metal biodeposition rates were extremely high (e.g., 50 mg Zn·m -2 ·day -1 ) in high-turbidity areas with elevated metal levels. Two factors contributed to metal biodeposition by zebra mussels. First, their production of feces and pseudofeces increased the rate at which suspended matter was being added to the sediment (accounting for 92% of the increased metal biodeposition). Second, the material coming out of suspension had higher metal concentrations when zebra mussels were present (constituting 8% of the increased biodeposition). (author)

Secondary cell with orthorhombic alkali metal/manganese oxide phase active cathode material

Science.gov (United States)

Doeff, Marca M.; Peng, Marcus Y.; Ma, Yanping; Visco, Steven J.; DeJonghe, Lutgard C.

1996-01-01

An alkali metal manganese oxide secondary cell is disclosed which can provide a high rate of discharge, good cycling capabilities, good stability of the cathode material, high specific energy (energy per unit of weight) and high energy density (energy per unit volume). The active material in the anode is an alkali metal and the active material in the cathode comprises an orthorhombic alkali metal manganese oxide which undergoes intercalation and deintercalation without a change in phase, resulting in a substantially linear change in voltage with change in the state of charge of the cell. The active material in the cathode is an orthorhombic structure having the formula M.sub.x Z.sub.y Mn.sub.(1-y) O.sub.2, where M is an alkali metal; Z is a metal capable of substituting for manganese in the orthorhombic structure such as iron, cobalt or titanium; x ranges from about 0.2 in the fully charged state to about 0.75 in the fully discharged state, and y ranges from 0 to 60 atomic %. Preferably, the cell is constructed with a solid electrolyte, but a liquid or gelatinous electrolyte may also be used in the cell.

Beyond the material grave: Life Cycle Impact Assessment of leaching from secondary materials in road and earth constructions.

Science.gov (United States)

Schwab, Oliver; Bayer, Peter; Juraske, Ronnie; Verones, Francesca; Hellweg, Stefanie

2014-10-01

In industrialized countries, large amounts of mineral wastes are produced. They are re-used in various ways, particularly in road and earth constructions, substituting primary resources such as gravel. However, they may also contain pollutants, such as heavy metals, which may be leached to the groundwater. The toxic impacts of these emissions are so far often neglected within Life Cycle Assessments (LCA) of products or waste treatment services and thus, potentially large environmental impacts are currently missed. This study aims at closing this gap by assessing the ecotoxic impacts of heavy metal leaching from industrial mineral wastes in road and earth constructions. The flows of metals such as Sb, As, Pb, Cd, Cr, Cu, Mo, Ni, V and Zn originating from three typical constructions to the environment are quantified, their fate in the environment is assessed and potential ecotoxic effects evaluated. For our reference country, Germany, the industrial wastes that are applied as Granular Secondary Construction Material (GSCM) carry more than 45,000 t of diverse heavy metals per year. Depending on the material quality and construction type applied, up to 150 t of heavy metals may leach to the environment within the first 100 years after construction. Heavy metal retardation in subsoil can potentially reduce the fate to groundwater by up to 100%. One major challenge of integrating leaching from constructions into macro-scale LCA frameworks is the high variability in micro-scale technical and geographical factors, such as material qualities, construction types and soil types. In our work, we consider a broad range of parameter values in the modeling of leaching and fate. This allows distinguishing between the impacts of various road constructions, as well as sites with different soil properties. The findings of this study promote the quantitative consideration of environmental impacts of long-term leaching in Life Cycle Assessment, complementing site-specific risk

Metal-decored graphites as anode materials for use in lithium-ion accumulators

International Nuclear Information System (INIS)

Licht, Bjoern Karl

2015-01-01

Graphitic materials are currently the most frequently used anode materials for lithium ion batteries (LIB). This type of battery is considered to be the ideal application for energy storage in electromobility or in mobile devices that require a high power density. Although intercalated graphite has only about 8 % of the gravimetric energy density of lithium metal, these materials are preferred due to safety reasons. However, by chemical modification of the surface, the electrochemical performance of graphite can be enhanced. In the thesis presented at hand, a novel synthesis route for the preparation of homogenous metal depositions on graphite is shown. The reaction proceeds via a gas phase reaction by the thermal decomposition of metal carboxylates. The decomposition process was analyzed by thermogravimetry and gas phase analysis. In comparison to the unmodified graphite, copper-coated graphite shows in increased capacity and cycle stability when used as anode materials in LIBs. Special emphasis should be placed on an improved adhesion of the active material on the copper current collector. The proven catalytic activity of the metal depositions not only enables a use in battery devices but could also be innovating for catalytic processes such as chlorine-alkali electrolysis.

An in situ method of creating metal oxide–carbon composites and their application as anode materials for lithium-ion batteries

KAUST Repository

Yang, Zichao

2011-01-01

Transition metal oxides are actively investigated as anode materials for lithium-ion batteries (LIBs), and their nanocomposites with carbon frequently show better performance in galvanostatic cycling studies, compared to the pristine metal oxide. An in situ, scalable method for creating a variety of transition metal oxide-carbon nanocomposites has been developed based on free-radical polymerization and cross-linking of poly(acrylonitrile) in the presence of the metal oxide precursor containing vinyl groups. The approach yields a cross-linked polymer network, which uniformly incorporates nanometre-sized transition metal oxide particles. Thermal treatment of the organic-inorganic hybrid material produces nearly monodisperse metal oxide nanoparticles uniformly embedded in a porous carbon matrix. Cyclic voltammetry and galvanostatic cycling electrochemical measurements in a lithium half-cell are used to evaluate the electrochemical properties of a Fe3O 4-carbon composite created using this approach. These measurements reveal that when used as the anode in a lithium battery, the material exhibits stable cycling performance at both low and high current densities. We further show that the polymer/nanoparticle copolymerization approach can be readily adapted to synthesize metal oxide/carbon nanocomposites based on different particle chemistries for applications in both the anode and cathode of LIBs. © 2011 The Royal Society of Chemistry.

Effects of the exotic zebra mussel (Dreissena polymorpha) on metal cycling in Lake Erie

Energy Technology Data Exchange (ETDEWEB)

Klerks, P.L. [Univ. of Southwestern Louisiana, Dept. of Biology, Lafayette, Louisiana (United States)]. E-mail: klerks@usl.edu; Fraleigh, P.C.; Lawniczak, J.E. [Univ. of Toledo, Dept. of Biology, Toledo, Ohio (United States)

1997-07-15

This research demonstrated the impact of high densities of the zebra mussel (Dreissena polymorpha) on the cycling of copper, nickel, and zinc in a lake environment. Experiments with mussels on sedimentation traps in western Lake Erie and with mussels in flow-through tanks receiving Lake Erie water showed that zebra mussels remove metals from the water column, incorporate metals in their tissues, and deposit metals on the lake bottom. Removal of metals from the water column was estimated at 10-17%{center_dot}day{sup -1} of the amounts present. This material was largely deposited on the lake bottom; zebra mussels more than doubled the rate at which metals were being added to the lake bottom. Metal biodeposition rates were extremely high (e.g., 50 mg Zn{center_dot}m{sup -2}{center_dot}day{sup -1}) in high-turbidity areas with elevated metal levels. Two factors contributed to metal biodeposition by zebra mussels. First, their production of feces and pseudofeces increased the rate at which suspended matter was being added to the sediment (accounting for 92% of the increased metal biodeposition). Second, the material coming out of suspension had higher metal concentrations when zebra mussels were present (constituting 8% of the increased biodeposition). (author)

Precious-metal-base advanced materials

International Nuclear Information System (INIS)

Nowicki, T.; Carbonnaux, C.

1993-01-01

Precious metals constitute also the base of several advanced materials used in the industry in hundreds of metric tons. Platinum alloys have been used as structural materials for equipments in the glass industry. The essential reason for this is the excellent resistance of platinum alloys to oxidation and electrolytical corrosion in molten glasses at temperatures as high as 1200-1500 C. The major drawback is a weak creep resistance. The unique way for significant improvement of platinum base materials creep resistance is a strengthening by an oxide dispersion (ODS). In the case of CLAL's patented ''Plativer'' materials, 0.05 wt% of Y 2 O 3 is incorporated within the alloy matrix by the flame spraying process. Further improvement of platinum base materials is related, in the authors opinion, to the development of precious metals base intermetallics. Another interesting applications of precious metals are silver base electrical contacts. They are in fact silver matrix composites containing varying amounts of well-dispersed particles of constituents such as CdO, SnO 2 , Ni, WC or C. In the case of such materials, particular properties are required and tested : resistance to arc erosion, resistance to welding and contact resistance. Many other technically fascinating precious metals base materials exist: brazing alloys for assembling metals, superconductors and ceramics; dental materials including magnetic biocompatible alloys; silver composites for superconductor wire jackets. The observation of current evolution indicates very clearly that precious metals cannot be replaced by common metals because of their unique characteristics due to their atomic level properties

METAL MATRIX COMPOSITE BRAKE ROTORS: HISTORICAL DEVELOPMENT AND PRODUCT LIFE CYCLE ANALYSIS

Directory of Open Access Journals (Sweden)

M.M. Rahman

2011-12-01

Full Text Available Metal matrix composites (MMCs have become attractive for engineering structural applications due to their excellent specific strength and are increasingly seen as an alternative to conventional materials, particularly in the automotive industry. In this study, a historical background on the development and application of metal matrix composites for automotive brake rotors is presented. The discussion also includes an analysis of the product life cycle with stir casting as a case study. The historical review analysis revealed that gradual development of material and processing techniques have led to lighter weight, lower cost and higher performance brake rotors as a result of a better understanding of the mechanics of metal matrix composites. It emerged from the study that the stir casting technique provides ease of operation, sustainability and, most significantly, very competitive costs without sacrificing quality relative to other techniques; as such, it is the most attractive manufacturing process in the industry. These findings can be used for future design and manufacture of an efficient and effective aluminium matrix composite brake rotor for automotive and other applications.

Knowledge-based metals & materials

OpenAIRE

Sasson, Amir

2011-01-01

This study presents the Norwegian metal and material industry (defined as all metal and material related firms located in Norway, regardless of ownership) and evaluates the industry according to the underlying dimensions of a global knowledge hub - cluster attractiveness, education attractiveness, talent attractiveness, R&D and innovation attractiveness, ownership attractiveness, environmental attractiveness and cluster dynamics.

Electrolyte additive enabled fast charging and stable cycling lithium metal batteries

Energy Technology Data Exchange (ETDEWEB)

Zheng, Jianming; Engelhard, Mark H.; Mei, Donghai; Jiao, Shuhong; Polzin, Bryant J.; Zhang, Ji-Guang; Xu, Wu

2017-03-01

Lithium (Li) metal battery is an attractive energy storage system owing to the ultrahigh specific capacity and the lowest redox potential of Li metal anode. However, safety concern associated with dendrite growth and limited cycle life especially at a high charge current density are two critical challenges hindering the practical applications of rechargeable Li metal batteries. Here, we report for the first time that an optimal amount (0.05 M) of LiPF6 as additive in the LiTFSI-LiBOB dual-salt/carbonate-based electrolyte can significantly enhance the charging capability and the long-term cycle life of Li metal batteries with a moderately high cathode loading of 1.75 mAh cm-2. Unprecedented stable-cycling (97.1% capacity retention after 500 cycles) along with very limited increase in electrode over-potential has been achieved at a high current density of 1.75 mA cm-2. This unparalleled fast charging and stable cycling performance is contributed from both the stabilized Al cathode current collector, and, more importantly, the robust and conductive SEI layer formed on Li metal anode in the presence of the LiPF6 additive.

Metal-silica sol-gel materials

Science.gov (United States)

Stiegman, Albert E. (Inventor)

2002-01-01

The present invention relates to a single phase metal-silica sol-gel glass formed by the co-condensation of a transition metal with silicon atoms where the metal atoms are uniformly distributed within the sol-gel glass as individual metal centers. Any transition metal may be used in the sol-gel glasses. The present invention also relates to sensor materials where the sensor material is formed using the single phase metal-silica sol-gel glasses. The sensor materials may be in the form of a thin film or may be attached to an optical fiber. The present invention also relates to a method of sensing chemicals using the chemical sensors by monitoring the chromatic change of the metal-silica sol-gel glass when the chemical binds to the sensor. The present invention also relates to oxidation catalysts where a metal-silica sol-gel glass catalyzes the reaction. The present invention also relates to a method of performing oxidation reactions using the metal-silica sol-gel glasses. The present invention also relates to organopolymer metal-silica sol-gel composites where the pores of the metal-silica sol-gel glasses are filled with an organic polymer polymerized by the sol-gel glass.

Comparative environmental life cycle assessment of composite materials

International Nuclear Information System (INIS)

De Vegt, O.M.; Haije, W.G.

1997-12-01

The aim of the present study is to compare and quantify the environmental impact of three rotorblades made of different materials and to establish which stage in the life cycle contributes most. The life cycle of a product can be represented by the production phase, including depletion of raw materials (mining) and production (machining) of products, the utilisation phase, including use of energy, maintenance and cleaning, and the disposal phase, including landfill, incineration, recycling, etc. The environmental impact of a product is not only determined by the materials selected but also by the function of the product itself. E.g. when natural fibres are applied in vehicles as a substitution for metals the environmental impact in the use phase will be reduced due to a lower energy consumption caused by a lower car weight. The influence on the environmental impact of the production phase must also be taken into account. The material relation between the production phase and the use phase and the disposal phase is complicated. In general the lifetime of a product use phase can be extended (positive aspect), e.g. by application of a coating onto the surface. Due to the coating the product can not easily be recycled, which is a negative aspect. The three types of composites used in the rotorblade of the wind energy converter considered in this study are: flaxfibre reinforced epoxy, carbon fibre reinforced epoxy and glassfibre reinforced polyester. The assessment is performed using the computer program Simapro 3, which is based on the Dutch CML method for the environmental life-cycle assessment of products using the Eco-Indicator 95 evaluation method. The CML method defines five phases for an LCA: goal definition and scoping; inventory; classification; impact assessment; and improvement analysis. The improvement analysis is not part of this work. Performing an LCA is a time-consuming process due to the detailed information that is required. In chapter five some

Bibliography on cycling of trace metals in freshwater ecosystems

International Nuclear Information System (INIS)

LaRiviere, M.G.; Scott, A.J.; Woodfield, W.G.; Cushing, C.E.

1978-07-01

This bibliography is a listing of pertinent literature directly addressing the cycling of trace metals in freshwater ecosystems. Data on cycling, including the influences of environmental mediators, are included. 151 references

Novel non-platinum metal catalyst material

DEFF Research Database (Denmark)

2014-01-01

The present invention relates to a novel non-platinum metal catalyst material for use in low temperature fuel cells and electrolysers and to fuel cells and electrolysers comprising the novel non-platinum metal catalyst material. The present invention also relates to a novel method for synthesizing...... the novel non-platinum metal catalyst material....

Radioactive materials in recycled metals.

Science.gov (United States)

Lubenau, J O; Yusko, J G

1995-04-01

In recent years, the metal recycling industry has become increasingly aware of an unwanted component in metal scrap--radioactive material. Worldwide, there have been 35 instances where radioactive sources were unintentionally smelted in the course of recycling metal scrap. In some cases contaminated metal consumer products were distributed internationally. In at least one case, serious radiation exposures of workers and the public occurred. Radioactive material appearing in metal scrap includes sources subject to licensing under the Atomic Energy Act and also naturally occurring radioactive material. U.S. mills that have smelted a radioactive source face costs resulting from decontamination, waste disposal, and lost profits that range from 7 to 23 million U.S. dollars for each event. To solve the problem, industry and the government have jointly undertaken initiatives to increase awareness of the problem within the metal recycling industry. Radiation monitoring of recycled metal scrap is being performed increasingly by mills and, to a lesser extent, by scrap processors. The monitoring does not, however, provide 100% protection. Improvements in regulatory oversight by the government could stimulate improved accounting and control of licensed sources. However, additional government effort in this area must be reconciled with competing priorities in radiation safety and budgetary constraints. The threat of radioactive material in recycled metal scrap will continue for the foreseeable future and, thus, poses regulatory policy challenges for both developed and developing nations.

The geochemical record of the ancient nitrogen cycle, nitrogen isotopes, and metal cofactors.

Science.gov (United States)

Godfrey, Linda V; Glass, Jennifer B

2011-01-01

The nitrogen (N) cycle is the only global biogeochemical cycle that is driven by biological functions involving the interaction of many microorganisms. The N cycle has evolved over geological time and its interaction with the oxygen cycle has had profound effects on the evolution and timing of Earth's atmosphere oxygenation (Falkowski and Godfrey, 2008). Almost every enzyme that microorganisms use to manipulate N contains redox-sensitive metals. Bioavailability of these metals has changed through time as a function of varying redox conditions, and likely influenced the biological underpinnings of the N cycle. It is possible to construct a record through geological time using N isotopes and metal concentrations in sediments to determine when the different stages of the N cycle evolved and the role metal availability played in the development of key enzymes. The same techniques are applicable to understanding the operation and changes in the N cycle through geological time. However, N and many of the redox-sensitive metals in some of their oxidation states are mobile and the isotopic composition or distribution can be altered by subsequent processes leading to erroneous conclusions. This chapter reviews the enzymology and metal cofactors of the N cycle and describes proper utilization of methods used to reconstruct evolution of the N cycle through time. Copyright © 2011 Elsevier Inc. All rights reserved.

Nanofluid based on self-nanoencapsulated metal/metal alloys phase change materials with tuneable crystallisation temperature.

Science.gov (United States)

Navarrete, Nuria; Gimeno-Furio, Alexandra; Mondragon, Rosa; Hernandez, Leonor; Cabedo, Luis; Cordoncillo, Eloisa; Julia, J Enrique

2017-12-14

Nanofluids using nanoencapsulated Phase Change Materials (nePCM) allow increments in both the thermal conductivity and heat capacity of the base fluid. Incremented heat capacity is produced by the melting enthalpy of the nanoparticles core. In this work two important advances in this nanofluid type are proposed and experimentally tested. It is firstly shown that metal and metal alloy nanoparticles can be used as self-encapsulated nePCM using the metal oxide layer that forms naturally in most commercial synthesis processes as encapsulation. In line with this, Sn/SnOx nanoparticles morphology, size and thermal properties were studied by testing the suitability and performance of encapsulation at high temperatures and thermal cycling using a commercial thermal oil (Therminol 66) as the base fluid. Secondly, a mechanism to control the supercooling effect of this nePCM type based on non-eutectic alloys was developed.

Advanced breeder cycle uses metallic fuel

International Nuclear Information System (INIS)

Chang, Y.I.

1991-01-01

Scientists from Argonne National Laboratory have been developing a concept called the Integral fast Reactor (IFR). This fast breeder reactor could effectively increase Uranium resources a hundred fold making nuclear power essentially an inexhaustible energy source. The IFR is outlined. In the IFR, the inherent properties of liquid metal cooling are combined with a new metallic fuel which is allowed to swell and gives an improved burnup level and a radically different refining process to allow breakthroughs in passive safety, fuel cycle economics and waste management. (author)

An in situ method of creating metal oxide–carbon composites and their application as anode materials for lithium-ion batteries

KAUST Repository

Yang, Zichao; Shen, Jingguo; Archer, Lynden A.

2011-01-01

Transition metal oxides are actively investigated as anode materials for lithium-ion batteries (LIBs), and their nanocomposites with carbon frequently show better performance in galvanostatic cycling studies, compared to the pristine metal oxide

Characterization of minerals, metals and materials

CERN Document Server

Hwang, Jiann-Yang; Bai, Chengguang; Carpenter, John; Cai, Mingdong; Firrao, Donato; Kim, Byoung-Gon

2012-01-01

This state-of-the-art reference contains chapters on all aspects of the characterization of minerals, metals, and materials. The title presents papers from one of the largest yearly gatherings of materials scientists in the world and thoroughly discusses the characterization of minerals, metals, and materials The scope includes current industrial applications and research and developments in the following areas:  Characterization of Ferrous Metals Characterization of Non-Ferrous Materials Characterization of Minerals and Ceramics Character

Multiaxial Cycle Deformation and Low-Cycle Fatigue Behavior of Mild Carbon Steel and Related Welded-Metal Specimen

Directory of Open Access Journals (Sweden)

Weilian Qu

2017-01-01

Full Text Available The low-cycle fatigue experiments of mild carbon Q235B steel and its related welded-metal specimens are performed under uniaxial, in-phase, and 90° out-of-phase loading conditions. Significant additional cyclic hardening for 90° out-of-phase loading conditions is observed for both base metal and its related weldment. Besides, welding process produces extra additional hardening under the same loading conditions compared with the base metal. Multiaxial low-cycle fatigue strength under 90° out-of-phase loading conditions is significantly reduced for both base-metal and welded-metal specimens. The weldment has lower fatigue life than the base metal under the given loading conditions, and the fatigue life reduction of weldment increases with the increasing strain amplitude. The KBM, FS, and MKBM critical plane parameters are evaluated for the fatigue data obtained. The FS and MKBM parameters are found to show better correlation with fatigue lives for both base-metal and welded-metal specimens.

Electrolyte additive enabled fast charging and stable cycling lithium metal batteries

Energy Technology Data Exchange (ETDEWEB)

Zheng, Jianming; Engelhard, Mark H.; Mei, Donghai; Jiao, Shuhong; Polzin, Bryant J.; Zhang, Ji-Guang; Xu, Wu

2017-03-01

Batteries using lithium (Li) metal as anodes are considered promising energy storage systems because of their high energy densities. However, safety concerns associated with dendrite growth along with limited cycle life, especially at high charge current densities, hinder their practical uses. Here we report that an optimal amount (0.05 M) of LiPF6 as an additive in LiTFSI-LiBOB dual-salt/carbonate-solvent-based electrolytes significantly enhances the charging capability and cycling stability of Li metal batteries. In a Li metal battery using a 4-V Li-ion cathode at a moderately high loading of 1.75mAh cm(-2), a cyclability of 97.1% capacity retention after 500 cycles along with very limited increase in electrode overpotential is accomplished at a charge/discharge current density up to 1.75 mA cm(-2). The fast charging and stable cycling performances are ascribed to the generation of a robust and conductive solid electrolyte interphase at the Li metal surface and stabilization of the Al cathode current collector.

Metal/graphite-composite materials for fusion device

International Nuclear Information System (INIS)

Kneringer, G.; Kny, E.; Fischer, W.; Reheis, N.; Staffler, R.; Samm, U.; Winter, J.

1995-01-01

The utilization of graphite as a structural material depends to an important extent on the availability of a joining technique suitable for the production of reliable large scale metal/graphite-composites. This study has been conducted to evaluate vacuum brazes and procedures for graphite and metals which can be used in fusion applications up to about 1500 degree C. The braze materials included: AgCuTi, CuTi, NiTi, Ti, ZrTi, Zr. Brazing temperatures ranged from 850 degree C to 1900 degree C. The influence of graphite quality on wettability and pore-penetration of the braze has been investigated. Screening tests of metal/graphite-assemblies with joint areas exceeding some square-centimeters have shown that they can only successfully be produced when graphite is brazed to a metal, such as tungsten or molybdenum with a coefficient of thermal expansion closely matching that of graphite. Therefore all experimental work on evaluation of joints has been concentrated on molybdenum/graphite brazings. The tensile strength of molybdenum/graphite-composites compares favorably with the tensile strength of bulk graphite from room temperature close to the melting temperature of the braze. In electron beam testing the threshold damage line for molybdenum/graphite-composites has been evaluated. Results show that even composites with the low melting AgCuTi-braze are expected to withstand 10 MW/m 2 power density for at least 10 3 cycles. Limiter testing in TEXTOR shows that molybdenum/graphite-segments with 3 mm graphite brazed on molybdenum-substrate withstand severe repeated TEXTOR plasma discharge conditions without serious damage. Results prove that actively cooled components on the basis of a molybdenum/graphite-composite can sustain a higher heat flux than bulk graphite alone. (author)

Equipment for the investigation of the thermomechanical fatigue of metallic materials

International Nuclear Information System (INIS)

Wolter, F.; Petersen, C.

1992-01-01

Within the framework of the European research program on nuclear fusion, a question is to be answered which is of great importance for the design of a fusion reactor, namely: To what extent is the 'First Wall structure' damaged by the pulsating mode of operation in this reactor type. This pulsating mode of operation leads to a thermal and mechanical cyclic stress in the metal support structure of the reactor. Thermomechanical cyclic stresses of a similar kind also occur in aircraft turbines, rocket drive units, and heat generating systems. For simulation of such stresses, a facility was developed in the Karlsruhe Nuclear Research Center which permits to produce thermomechanical cyclic stresses in uniaxial metallic materials specimens. The results of investigations with a martensitic 12%-Cr steel are explained. The stress range variations show a degressive behavior at the onset of fatigue and develop into a linear decline. The plastic strain reached a plateau after a number of cycles which was dependent on the mechanical strain (linear behavior). Relationships can be described by a simple transformation of number of cycles to failure between mechanical strain and number of stress cycles to failure. (orig./MM) [de

Evaluation of Package Stress during Temperature Cycling using Metal Deformation Measurement and FEM Simulation

International Nuclear Information System (INIS)

Hoeglauer, J.; Bohm, C.; Otremba, R.; Maerz, J.; Nelle, P.; Stecher, M.; Alpern, P.

2006-01-01

Plastic encapsulated devices that are exposed to Temperature Cycling (TC) tests undergo an excessive mechanical stress due to different Coefficients of Thermal Expansion (CTE) of the various materials used in the system. Especially in the corners of the die, passivation cracks and shifted metal lines can be observed, which demonstrates an increasing mechanical stress from chip center to the corners of the die. This effect has been known for a long time. This paper presents a simple measurement technique to quantify the mechanical shear stress at the chip-Mold Compound (MC) interface by measuring the deformation of a periodical metal structure. Based on this deformation measurement, we evaluated the stress distribution within the package, and the influence of different parameters such as number of cycles and chip size. Furthermore, these experimental results were compared with FEM simulation, and showed good agreement but could not account in all cases for the total amount of observed shift

Roofing Materials Assessment: Investigation of Five Metals in Runoff from Roofing Materials.

Science.gov (United States)

Winters, Nancy; Granuke, Kyle; McCall, Melissa

2015-09-01

To assess the contribution of five toxic metals from new roofing materials to stormwater, runoff was collected from 14 types of roofing materials and controls during 20 rain events and analyzed for metals. Many of the new roofing materials evaluated did not show elevated metals concentrations in the runoff. Runoff from several other roofing materials was significantly higher than the controls for arsenic, copper, and zinc. Notably, treated wood shakes released arsenic and copper, copper roofing released copper, PVC roofing released arsenic, and Zincalume® and EPDM roofing released zinc. For the runoff from some of the roofing materials, metals concentrations decreased significantly over an approximately one-year period of aging. Metals concentrations in runoff were demonstrated to depend on a number of factors, such as roofing materials, age of the materials, and climatic conditions. Thus, application of runoff concentrations from roofing materials to estimate basin-wide releases should be undertaken cautiously.

Investigating the Dendritic Growth during Full Cell Cycling of Garnet Electrolyte in Direct Contact with Li Metal.

Science.gov (United States)

Aguesse, Frederic; Manalastas, William; Buannic, Lucienne; Lopez Del Amo, Juan Miguel; Singh, Gurpreet; Llordés, Anna; Kilner, John

2017-02-01

All-solid-state batteries including a garnet ceramic as electrolyte are potential candidates to replace the currently used Li-ion technology, as they offer safer operation and higher energy storage performances. However, the development of ceramic electrolyte batteries faces several challenges at the electrode/electrolyte interfaces, which need to withstand high current densities to enable competing C-rates. In this work, we investigate the limits of the anode/electrolyte interface in a full cell that includes a Li-metal anode, LiFePO 4 cathode, and garnet ceramic electrolyte. The addition of a liquid interfacial layer between the cathode and the ceramic electrolyte is found to be a prerequisite to achieve low interfacial resistance and to enable full use of the active material contained in the porous electrode. Reproducible and constant discharge capacities are extracted from the cathode active material during the first 20 cycles, revealing high efficiency of the garnet as electrolyte and the interfaces, but prolonged cycling leads to abrupt cell failure. By using a combination of structural and chemical characterization techniques, such as SEM and solid-state NMR, as well as electrochemical and impedance spectroscopy, it is demonstrated that a sudden impedance drop occurs in the cell due to the formation of metallic Li and its propagation within the ceramic electrolyte. This degradation process is originated at the interface between the Li-metal anode and the ceramic electrolyte layer and leads to electromechanical failure and cell short-circuit. Improvement of the performances is observed when cycling the full cell at 55 °C, as the Li-metal softening favors the interfacial contact. Various degradation mechanisms are proposed to explain this behavior.

LIFE Materials: Fuel Cycle and Repository Volume 11

Energy Technology Data Exchange (ETDEWEB)

Shaw, H; Blink, J A

2008-12-12

The fusion-fission LIFE engine concept provides a path to a sustainable energy future based on safe, carbon-free nuclear power with minimal nuclear waste. The LIFE design ultimately offers many advantages over current and proposed nuclear energy technologies, and could well lead to a true worldwide nuclear energy renaissance. When compared with existing and other proposed future nuclear reactor designs, the LIFE engine exceeds alternatives in the most important measures of proliferation resistance and waste minimization. The engine needs no refueling during its lifetime. It requires no removal of fuel or fissile material generated in the LIFE engine. It leaves no weapons-attractive material at the end of life. Although there is certainly a need for additional work, all indications are that the 'back end' of the fuel cycle does not to raise any 'showstopper' issues for LIFE. Indeed, the LIFE concept has numerous benefits: (1) Per unit of electricity generated, LIFE engines would generate 20-30 times less waste (in terms of mass of heavy metal) requiring disposal in a HLW repository than does the current once-through fuel cycle. (2) Although there may be advanced fuel cycles that can compete with LIFE's low mass flow of heavy metal, all such systems require reprocessing, with attendant proliferation concerns; LIFE engines can do this without enrichment or reprocessing. Moreover, none of the advanced fuel cycles can match the low transuranic content of LIFE waste. (3) The specific thermal power of LIFE waste is initially higher than that of spent LWR fuel. Nevertheless, this higher thermal load can be managed using appropriate engineering features during an interim storage period, and could be accommodated in a Yucca-Mountain-like repository by appropriate 'staging' of the emplacement of waste packages during the operational period of the repository. The planned ventilation rates for Yucca Mountain would be sufficient for LIFE waste

LIFE Materials: Fuel Cycle and Repository Volume 11

International Nuclear Information System (INIS)

Shaw, H.; Blink, J.A.

2008-01-01

The fusion-fission LIFE engine concept provides a path to a sustainable energy future based on safe, carbon-free nuclear power with minimal nuclear waste. The LIFE design ultimately offers many advantages over current and proposed nuclear energy technologies, and could well lead to a true worldwide nuclear energy renaissance. When compared with existing and other proposed future nuclear reactor designs, the LIFE engine exceeds alternatives in the most important measures of proliferation resistance and waste minimization. The engine needs no refueling during its lifetime. It requires no removal of fuel or fissile material generated in the LIFE engine. It leaves no weapons-attractive material at the end of life. Although there is certainly a need for additional work, all indications are that the 'back end' of the fuel cycle does not to raise any 'showstopper' issues for LIFE. Indeed, the LIFE concept has numerous benefits: (1) Per unit of electricity generated, LIFE engines would generate 20-30 times less waste (in terms of mass of heavy metal) requiring disposal in a HLW repository than does the current once-through fuel cycle. (2) Although there may be advanced fuel cycles that can compete with LIFE's low mass flow of heavy metal, all such systems require reprocessing, with attendant proliferation concerns; LIFE engines can do this without enrichment or reprocessing. Moreover, none of the advanced fuel cycles can match the low transuranic content of LIFE waste. (3) The specific thermal power of LIFE waste is initially higher than that of spent LWR fuel. Nevertheless, this higher thermal load can be managed using appropriate engineering features during an interim storage period, and could be accommodated in a Yucca-Mountain-like repository by appropriate 'staging' of the emplacement of waste packages during the operational period of the repository. The planned ventilation rates for Yucca Mountain would be sufficient for LIFE waste to meet the thermal constraints of

Nanocomposite of graphene and metal oxide materials

Science.gov (United States)

Liu, Jun; Aksay, Ilhan A.; Choi, Daiwon; Wang, Donghai; Yang, Zhenguo

2012-09-04

Nanocomposite materials comprising a metal oxide bonded to at least one graphene material. The nanocomposite materials exhibit a specific capacity of at least twice that of the metal oxide material without the graphene at a charge/discharge rate greater than about 10C.

Nanocomposite of graphene and metal oxide materials

Science.gov (United States)

Liu, Jun; Aksay, Ilhan A.; Choi, Daiwon; Wang, Donghai; Yang, Zhenguo

2013-10-15

Nanocomposite materials comprising a metal oxide bonded to at least one graphene material. The nanocomposite materials exhibit a specific capacity of at least twice that of the metal oxide material without the graphene at a charge/discharge rate greater than about 10 C.

Metallic materials for mechanical damping capacity applications

Science.gov (United States)

Crăciun, R. C.; Stanciu, S.; Cimpoeșu, R.; (Dragoș Ursanu, A. I.; Manole, V.; Paraschiv, P.; Chicet, D. L.

2016-08-01

Some metallic materials exhibit good damping capacity of mechanical energy into thermal energy. This property along with the others metallic characteristics make this materials interesting for a big number of applications. These materials can be used as bumpers in different applications including automotive field. Beside grey cast iron and shape memory alloys few new metallic materials are presented for the supposition of high damping capacity. We analyze the causes that increase the internal friction of some metallic materials and possibilities to enhance this property through different mechanical, physical or chemical methods. Shape memory alloys, especially those based on copper, present a different damping capacity on martensite, austenite or transition state. In the transformation range M ↔A, which in case of copper base shape memory alloys is quite large, the metallic intelligent materials present a high internal friction, almost comparable with natural rubber behavior that can transform mechanical energy into thermal energy till a certain value of the external solicitation. These materials can be used as noise or small vibrations bumpers or even as shock absorbers in automotive industry.

Metal-binding silica materials for wastewater cleanup

Energy Technology Data Exchange (ETDEWEB)

Kroh, F.O. [TPL, Inc., Albuquerque, NM (United States)

1997-10-01

In this Phase I Small Business Innovation Research program, TPL, Inc. is developing two series of high-efficiency covalently modified silica materials for removing heavy metal ions from wastewater. These materials have metal ion capacities greatly exceeding those of commercial ion exchange resins. One series, containing thiol groups, has high capacity for {open_quotes}soft{close_quotes} heavy metal ions such as Hg, Pb, Ag, and Cd; the other, containing quaternary ammonium groups, has high capacity for anionic metal ions such as pertechnetate, arsenate, selenite, and chromate. These materials have high selectivity for the contaminant metals and will function well in harsh systems that inactivate other systems.

Challenges in high temperature low cycle fatigue testing of metallic materials

International Nuclear Information System (INIS)

Sandhya, R.; Valsan, M.; Bhanu Sankara Rao, K.

2007-01-01

The evaluation of the high strain Low Cycle Fatigue properties of structural materials is an involved and complicated procedure requiring skill and diligence from the experimentalist. This presentation describes the various testing methods to evaluate the LCF properties of structural materials, the complexities involved and some solutions to exacting requirements, not covered by the testing procedure standards. The basic components of servo-hydraulic fatigue testing machines is described, as are the calibration and maintenance procedures. Results of LCF tests conducted at the authors' laboratory on AISI 316L(N) stainless steel and Mod.9Cr-1Mo ferritic steel are described. The complications in total strain controlled testing of weld joints is brought out and soft zone development in Mod. 9Cr-1Mo ferritic steel is described. The special requirements for testing in environmental chambers is a challenging task. In-house chambers, designed to carry out testing in dynamic sodium environment is highlighted. These chambers have provision to accommodate extensometers for strain measurements, and also house all the safety instrumentation needed to carry out to mechanical testing in dynamic sodium environment. The variation of LCF results as a function of specimen geometry is examined. The various failure criteria adopted by laboratories in different countries are also touched upon. (author)

Low-cycle fatigue-cracking mechanisms in fcc crystalline materials

Science.gov (United States)

Zhang, P.; Qu, S.; Duan, Q. Q.; Wu, S. D.; Li, S. X.; Wang, Z. G.; Zhang, Z. F.

2011-01-01

The low-cycle fatigue (LCF) cracking behavior in various face-centered-cubic (fcc) crystalline materials, including Cu single crystals, bicrystals and polycrystals, Cu-Al and Cu-Zn alloys, ultrafine-grained (UFG) Al-Cu and Cu-Zn alloys, was systematically investigated and reviewed. In Cu single crystals, fatigue cracking always nucleates along slip bands and deformation bands. The large-angle grain boundary (GB) becomes the preferential site in bicrystals and polycrystals. In addition, fatigue cracking can also nucleate along slip bands and twin boundaries (TBs) in polycrystalline materials. However, shear bands and coarse deformation bands are observed to the preferential sites for fatigue cracking in UFG materials with a large number of GBs. Based on numerous observations on fatigue-cracking behavior, the fatigue-cracking mechanisms along slip bands, GBs, TBs, shear bands and deformation bands were systematically compared and classified into two types, i.e. shear crack and impingement crack. Finally, these fatigue-cracking behaviors are discussed in depth for a better understanding of their physical nature and the transition from intergranular to transgranular cracking in various fcc crystalline materials. These comprehensive results for fatigue damage mechanisms should significantly aid in obtaining the optimum design to further strengthen and toughen metallic materials in practice.

Electrode for disintegrating metallic material

International Nuclear Information System (INIS)

Persang, J.C.

1985-01-01

A graphite electrode is provided for disintegrating and removing metallic material from a workpiece, e.g., such as portions of a nuclear reactor to be repaired while in an underwater and/or radioactive environment. The electrode is provided with a plurality of openings extending outwardly, and a manifold for supplying a mixture of water and compressed gas to be discharged through the openings for sweeping away the disintegrated metallic material during use of the electrode

Effects of thermal cycling on aluminum metallization of power diodes

DEFF Research Database (Denmark)

Brincker, Mads; Pedersen, Kristian Bonderup; Kristensen, Peter Kjær

2015-01-01

Reconstruction of aluminum metallization on top of power electronic chips is a well-known wear out phenomenon under power cycling conditions. However, the origins of reconstruction are still under discussion. In the current study, a method for carrying out passive thermal cycling of power diodes...

Space-Spurred Metallized Materials

Science.gov (United States)

1990-01-01

Spurred R&D toward improved vacuum metallizing techniques led to an extensive line of commercial products, from insulated outdoor garments to packaging for foods, from wall coverings to window shades, from life rafts to candy wrappings, reflective blankets to photographic reflectors. Metallized Products, Inc. (MPI) was one of the companies that worked with NASA in development of the original space materials. MPI markets its own metallized products and supplies materials to other manufacturers. One of the most widely used MPI products is TXG laminate. An example is a reflective kite, the S.O.S. Signal Kite that can be flown as high as 200 feet to enhance radar and visual detectability. It offers a boon to campers, hikers, mountain climbers and boaters. It is produced by Solar Reflections, Inc. The company also markets a solar reflective hat. Another example is by Pro-Tektion, Inc. to provide protection for expensive musical equipment that have sensitive electronic components subject to damage from the heat of stage lights, dust, or rain at outdoor concerts. MP supplied the material and acceptance of the covers by the sound industry has been excellent.

Superelastic load cycling of Gum Metal

International Nuclear Information System (INIS)

Vorontsov, V.A.; Jones, N.G.; Rahman, K.M.; Dye, D.

2015-01-01

The superelastic beta titanium alloy, Gum Metal, has been found to accumulate plastic strain during tensile load cycling in the superelastic regime. This is evident from the positive drift of the macroscopic stress vs. strain hysteresis curve parallel to the strain axis and the change in its geometry subsequent to every load–unload cycle. In addition, there is a progressive reduction in the hysteresis loop width and in the stress at which the superelastic transition occurs. In situ synchrotron X-ray diffraction has shown that the lattice strain exhibited the same behaviour as that observed in macroscopic measurements and identified further evidence of plastic strain accumulation. The mechanisms responsible for the observed behaviour have been evaluated using transmission electron microscopy, which revealed a range of different defects that formed during load cycling. The formation of these defects is consistent with the classical mathematical theory for the bcc to orthorhombic martensitic transformation. It is the accumulation of these defects over time that alters its superelastic behaviour

Development of a Hemispherical Metal Diaphragm for Single-Cycle Liquid-Metal Positive Expulsion Systems

National Research Council Canada - National Science Library

Gorland, Sol

1965-01-01

This report presents experimental results pertaining to the design and development of a metallic expulsion diaphragm for single-cycle positive expulsion of high-temperature liquid in an agravity condition...

Atomic scale modelling of materials of the nuclear fuel cycle

International Nuclear Information System (INIS)

Bertolus, M.

2011-10-01

This document written to obtain the French accreditation to supervise research presents the research I conducted at CEA Cadarache since 1999 on the atomic scale modelling of non-metallic materials involved in the nuclear fuel cycle: host materials for radionuclides from nuclear waste (apatites), fuel (in particular uranium dioxide) and ceramic cladding materials (silicon carbide). These are complex materials at the frontier of modelling capabilities since they contain heavy elements (rare earths or actinides), exhibit complex structures or chemical compositions and/or are subjected to irradiation effects: creation of point defects and fission products, amorphization. The objective of my studies is to bring further insight into the physics and chemistry of the elementary processes involved using atomic scale modelling and its coupling with higher scale models and experimental studies. This work is organised in two parts: on the one hand the development, adaptation and implementation of atomic scale modelling methods and validation of the approximations used; on the other hand the application of these methods to the investigation of nuclear materials under irradiation. This document contains a synthesis of the studies performed, orientations for future research, a detailed resume and a list of publications and communications. (author)

Properties of structural materials in liquid metal environment

International Nuclear Information System (INIS)

Borgstedt, H.U.

1991-12-01

The proceedings contain 16 contributions to the following topics: 1. Creep-Rupture Behaviour of Structural Materials in Liquid Metal Environment; 2. Behaviour of Materials in Liquid Metal Environment under Off-Normal Conditions; 3. Fatigue and Creep-Fatigue of Structural Materials in Liquid Metal Environment; and 4. Crack Propagation in Liquid Sodium. (MM)

Composite metal foil and ceramic fabric materials

Science.gov (United States)

Webb, Brent J.; Antoniak, Zen I.; Prater, John T.; DeSteese, John G.

1992-01-01

The invention comprises new materials useful in a wide variety of terrestrial and space applications. In one aspect, the invention comprises a flexible cloth-like material comprising a layer of flexible woven ceramic fabric bonded with a layer of metallic foil. In another aspect, the invention includes a flexible fluid impermeable barrier comprising a flexible woven ceramic fabric layer having metal wire woven therein. A metallic foil layer is incontinuously welded to the woven metal wire. In yet another aspect, the invention includes a material comprising a layer of flexible woven ceramic fabric bonded with a layer of an organic polymer. In still another aspect, the invention includes a rigid fabric structure comprising a flexible woven ceramic fabric and a resinous support material which has been hardened as the direct result of exposure to ultraviolet light. Inventive methods for producing such material are also disclosed.

Enhanced thermoelectric properties of metal film on bismuth telluride-based materials

International Nuclear Information System (INIS)

Chao, Wen Hsuan; Chen, Yi Ray; Tseng, Shih Chun; Yang, Ping Hsing; Wu, Ren Jye; Hwang, Jenn Yeu

2014-01-01

Diffusion barriers have a significant influence on the reliability and life time of thermoelectric modules. Although nickel is commonly used as a diffusion barrier in commercial thermoelectric modules, several studies have verified that Ni migrates to bismuth telluride-based material during high temperature cycles and causes a loss in efficacy. In this paper, the influence of metal layers coated to p-type and n-type Bi 2 Te 3 on the interface characterization and thermoelectric property is studied using a RF magnetron sputtering. The findings from this study demonstrate the structural and thermoelectric properties of p-type and n-type Bi 2 Te 3 coated with different metal layers. The crystalline phase and compositional change of the interface between the Bi 2 Te 3 materials and the metal layers were determined using an X-ray diffractometer and scanning electron microscopy with energy dispersive spectroscopy. Formation of NiTe was observed in the sample of Ni/p-type Bi 2 Te 3 based films post-annealed in an N 2 atmosphere at 200 °C. In contrast, no Co x Te y was formed in the sample of Co/p-type Bi 2 Te 3 based films post-annealed at 200 °C. For as-deposited Ni/p-type and n-type Bi 2 Te 3 based legs, the Ni slightly diffused into the Bi 2 Te 3 based legs. A similar phenomenon also occurred in the as-deposited Co/p-type and n-type Bi 2 Te 3 based legs. The Seebeck coefficients of the Co contacts on the Bi 2 Te 3 based material displayed better behavior than those of the Ni contacts on the Bi 2 Te 3 based legs. Thus Co could be a suitable diffusion barrier for bulk Bi 2 Te 3 based material. The observed effects on the thermoelectric and structural properties of metal/Bi 2 Te 3 based material are crucial for understanding the interface between the diffusion barrier and thermoelectric materials. - Highlights: • Interface characterization of metal coated to p-type and n-type Bi 2 Te 3 is studied. • We examined the phase transformation of metal/Bi 2 Te 3 based films

Superior cycle performance of Sn-C/graphene nanocomposite as an anode material for lithium-ion batteries

International Nuclear Information System (INIS)

Liang Shuzhao; Zhu Xuefeng; Lian Peichao; Yang Weishen; Wang Haihui

2011-01-01

A novel anode material for lithium-ion batteries, tin nanoparticles coated with carbon embedded in graphene (Sn-C/graphene), was fabricated by hydrothermal synthesis and subsequent annealing. The structure and morphology of the nanocomposite were characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The size of the Sn-C nanoparticles is about 50-200 nm. The reversible specific capacity of the nanocomposite is ∼662 mAh g -1 at a specific current of 100 mA g -1 after 100 cycles, even ∼417 mAh g -1 at the high current of 1000 mA g -1 . These results indicate that Sn-C/graphene possesses superior cycle performance and high rate capability. The enhanced electrochemical performances can be ascribed to the characteristic structure of the nanocomposite with both of the graphene and carbon shells, which buffer the volume change of the metallic tin and prevent the detachment and agglomeration of pulverized tin. - Graphical abstract: Tin nanoparticles coated with carbon embedded in graphene have been successfully fabricated by hydrothermal synthesis and subsequent annealing. This nanocomposite as an anode material for lithium-ion batteries exhibits superior cycle performance. Highlights: → A novel Sn-C/graphene nanocomposite as an anode material for lithium-ion batteries. → Carbon coating and graphene improve the cycle performance of the Sn anode material. → Possess large capacity, superior cycle performance, and high rate capability.

Ceramic superconductor/metal composite materials employing the superconducting proximity effect

Science.gov (United States)

Holcomb, Matthew J.

2002-01-01

Superconducting composite materials having particles of superconducting material disposed in a metal matrix material with a high electron-boson coupling coefficient (.lambda.). The superconducting particles can comprise any type of superconductor including Laves phase materials, Chevrel phase materials, A15 compounds, and perovskite cuprate ceramics. The particles preferably have dimensions of about 10-500 nanometers. The particles preferably have dimensions larger than the superconducting coherence length of the superconducting material. The metal matrix material has a .lambda. greater than 0.2, preferably the .lambda. is much higher than 0.2. The metal matrix material is a good proximity superconductor due to its high .lambda.. When cooled, the superconductor particles cause the metal matrix material to become superconducting due to the proximity effect. In cases where the particles and the metal matrix material are chemically incompatible (i.e., reactive in a way that destroys superconductivity), the particles are provided with a thin protective metal coating. The coating is chemically compatible with the particles and metal matrix material. High Temperature Superconducting (HTS) cuprate ceramic particles are reactive and therefore require a coating of a noble metal resistant to oxidation (e.g., silver, gold). The proximity effect extends through the metal coating. With certain superconductors, non-noble metals can be used for the coating.

Determination of the long-term release of metal(loid)s from construction materials using DGTs.

Science.gov (United States)

Schmukat, A; Duester, L; Ecker, D; Heininger, P; Ternes, T A

2013-09-15

Long-term leaching experiments are crucial to estimate the potential release of dangerous substances from construction materials. The application of Diffuse Gradients in Thin film (DGT) in static-batch experiments was tested to study the long-term release of metal(loid)s from construction materials for hydraulic engineering, for half a year. Long-term release experiments are essential to improve calculations of the life-time release for this materials. DGTs in batch experiments were found to be a space and labour efficient application, which enabled (i) to study, in a non-invasive manner, the total release of nine metal(loid)s for half a year, (ii) to differentiate between release mechanisms and (iii) to study mechanisms which were contrary to the release or caused experimental artefacts in the batch experiments. For copper slag (test material) it was found that eight metal(loid)s were released over the whole time period of 184 d. Cu, Ni and Pb were found to be released, predominantly caused by (the) weathering of sulphide minerals. Only for Zn a surface depletion mechanism was identified. The results from the long-term batch experiments deliver new information on the release of metal(loid)s during the life cycle of construction materials with regard to river basin management objectives. Copyright © 2013 Elsevier B.V. All rights reserved.

Volcanic Metal Emissions and Implications for Geochemical Cycling and Mineralization

Science.gov (United States)

Edmonds, M.; Mather, T. A.

2016-12-01

Volcanoes emit substantial fluxes of metals to the atmosphere in volcanic gas plumes in the form of aerosol, adsorbed onto silicate particles and even in some cases as gases.. A huge database of metal emissions has been built over the preceding decades, which shows that volcanoes emit highly volatile metals into the atmosphere, such as As, Bi, Cd, Hg, Re, Se, Tl, among others. Understanding the cycling of metals through the Solid Earth system has importance for tackling a wide range of Earth Science problems, e.g. (1) the environmental impacts of metal emissions; (2) the sulfur and metal emissions of volcanic eruptions; (3) the behavior of metals during subduction and slab devolatilization; (4) the influence of redox on metal behavior in subduction zones; (5) the partitioning of metals between magmatic vapor, brines and melts; and (6) the relationships between volcanism and ore deposit formation. It is clear, when comparing the metal composition and flux in the gases and aerosols emitted from volcanoes, that they vary with tectonic setting. These differences allow insights into how the magmatic vapor was generated and how it interacted with melts and sulfides during magma differentiation and decompression. Hotspot volcanoes (e.g. Kilauea, Hawaii; volcanoes in Iceland) outgas a metal suite that mirrors the sulfide liquid-silicate melt partitioning behaviors reconstructed from experiments (as far as they are known), suggesting that the aqueous fluids (that will later be outgassed from the volcano) receive metals directly from oxidation of sulfide liquids during degassing and ascent of magmas towards the surface. At arc volcanoes, the gaseous fluxes of metals are typically much higher; and there are greater enrichments in elements that partition strongly into vapor or brine from silicate melts such as Cu, Au, Zn, Pb, W. We collate and present data on volcanic metal emissions from volcanoes worldwide and review the implications of the data array for metal cycling

Fast thermal cycling-enhanced electromigration in power metallization

NARCIS (Netherlands)

Nguyen, Van Hieu; Salm, Cora; Krabbenborg, B.H.; Krabbenborg, B.H.; Bisschop, J.; Mouthaan, A.J.; Kuper, F.G.

Fast thermal nterconnects used in power ICs are susceptible to short circuit failure due to a combination of fast thermal cycling and electromigration stresses. In this paper, we present a study of electromigration-induced extrusion short-circuit failure in a standard two level metallization

A stable organic-inorganic hybrid layer protected lithium metal anode for long-cycle lithium-oxygen batteries

Science.gov (United States)

Zhu, Jinhui; Yang, Jun; Zhou, Jingjing; Zhang, Tao; Li, Lei; Wang, Jiulin; Nuli, Yanna

2017-10-01

A stable organic-inorganic hybrid layer (OIHL) is direct fabricated on lithium metal surface by the interfacial reaction of lithium metal foil with 1-chlorodecane and oxygen/carbon dioxide mixed gas. This favorable OIHL is approximately 30 μm thick and consists of lithium alkyl carbonate and lithium chloride. The lithium-oxygen batteries with OIHL protected lithium metal anode exhibit longer cycle life (340 cycles) than those with bare lithium metal anode (50 cycles). This desirable performance can be ascribed to the robust OIHL which prevents the growth of lithium dendrites and the corrosion of lithium metal.

Cast bulk metallic glass alloys: prospects as wear materials

Energy Technology Data Exchange (ETDEWEB)

Hawk, Jeffrey A.; Dogan, Omer N.; Shiflet, Gary J. (Dept. of Materials Science and Engineering, University of Virginia, Charlottesville, VA)

2005-01-01

Bulk metallic glasses are single phase materials with unusual physical and mechanical properties. One intriguing area of possible use is as a wear material. Usually, pure metals and single phase dilute alloys do not perform well in tribological conditions. When the metal or alloy is lightweight, it is usually soft leading to galling in sliding situations. For the harder metals and alloys, their density is usually high, so there is an energy penalty when using these materials in wear situations. However, bulk metallic glasses at the same density are usually harder than corresponding metals and dilute single phase alloys, and so could offer better wear resistance. This work will discuss preliminary wear results for metallic glasses with densities in the range of 4.5 to 7.9 g/cc. The wear behavior of these materials will be compared to similar metals and alloys.

Leading research on super metal. 3. Amorphous and nanostructured metallic materials; Super metal no sendo kenkyu. 3. Kogata buzai

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-03-01

Very fine structure control technique for amorphous and nanostructured metallic materials was reviewed to exceed the marginal performance of small metallic member materials. In Japan, high strength alloys and anticorrosion alloys are currently developed as an amorphous structure control technique, and ultra fine powder production and nano-compaction molding are studied for nanostructured materials. Fabrication of amorphous alloy wire materials and metal glass in USA are also introduced. Fabrication of metallic nanocrystals deposited within gas phase in Germany are attracting attention. The strength and abrasion resistance are remarkably enhanced by making nanostructured crystals and dispersing them. It may be most suitable to utilize amorphous and nanostructured metallic materials for earth-friendly materials having anticorrosion, and catalyst and biomaterial affinities, and also for magnetic materials. It is important for controlling micro-structures to clarify the formation mechanism of structures. For their processing techniques, the diversity and possibility are suggested, as to the condensation and solidification of gaseous and liquid phase metals, the molding and processing of very fine solid phase alloys, and the manufacturing members by heat treatment. 324 refs., 109 figs., 21 tabs.

Method of electrolytic decontamination of contaminated metal materials for radioactivity

International Nuclear Information System (INIS)

Harada, Yoshio; Ishibashi, Masaru; Matsumoto, Hiroyo.

1985-01-01

Purpose: To electrolytically eliminate radioactive materials from metal materials contaminated with radioactive materials, as well as efficiently remove metal ions leached out in an electrolyte. Method: In the case of anodic dissolution of metal materials contaminated with radioactivity in an electrolyte to eliminate radioactive contaminating materials on the surface of the metal materials, a portion of an electrolytic cell is defined with partition membranes capable of permeating metal ions therethrough. A cathode connected to a different power source is disposed to the inside of the partition membranes and fine particle of metals are suspended and floated in the electrolyte. By supplying an electric current between an insoluble anode disposed outside of the partition membranes and the cathode, metal ions permeating from the outside of the partition membranes are deposited on the fine metal particles. Accordingly, since metal ions in the electrolyte are removed, the electrolyte can always be kept clean. (Yoshihara, H.)

Solar Metal Sulfate-Ammonia Based Thermochemical Water Splitting Cycle for Hydrogen Production

Science.gov (United States)

Huang, Cunping (Inventor); T-Raissi, Ali (Inventor); Muradov, Nazim (Inventor)

2014-01-01

Two classes of hybrid/thermochemical water splitting processes for the production of hydrogen and oxygen have been proposed based on (1) metal sulfate-ammonia cycles (2) metal pyrosulfate-ammonia cycles. Methods and systems for a metal sulfate MSO.sub.4--NH3 cycle for producing H2 and O2 from a closed system including feeding an aqueous (NH3)(4)SO3 solution into a photoctalytic reactor to oxidize the aqueous (NH3)(4)SO3 into aqueous (NH3)(2)SO4 and reduce water to hydrogen, mixing the resulting aqueous (NH3)(2)SO4 with metal oxide (e.g. ZnO) to form a slurry, heating the slurry of aqueous (NH4)(2)SO4 and ZnO(s) in the low temperature reactor to produce a gaseous mixture of NH3 and H2O and solid ZnSO4(s), heating solid ZnSO4 at a high temperature reactor to produce a gaseous mixture of SO2 and O2 and solid product ZnO, mixing the gaseous mixture of SO2 and O2 with an NH3 and H2O stream in an absorber to form aqueous (NH4)(2)SO3 solution and separate O2 for aqueous solution, recycling the resultant solution back to the photoreactor and sending ZnO to mix with aqueous (NH4)(2)SO4 solution to close the water splitting cycle wherein gaseous H2 and O2 are the only products output from the closed ZnSO4--NH3 cycle.

Economic Growth and the Evolution of Material Cycles

DEFF Research Database (Denmark)

Zhang, Chao; Chen, Wei Qiang; Liu, Gang

2017-01-01

Understanding the relationship between material cycles and economic growth is essential for relieving environmental pressures associated with material extraction, production, and consumption. We developed an integrated analytical framework of dematerialization analysis incorporating both material...... flow and stock indicators. A four-quadrant diagram is designed to classify different stages of dematerialization based on the elasticity of material flow/stock to economic output or well-being. We then conducted a case study on the long-term evolution of aluminum cycle in the U.S., and found...... and secondary material recycling, take effect at different stages of economic development. Comprehensive understanding of dematerialization depends on in-depth analysis on material-economy relationships from an integrated stock and flow perspective....

Application of biowaste materials for the sorption of heavy metals in contaminated aqueous medium

International Nuclear Information System (INIS)

Saeed, A.; Iqbal, M.; Akhtar, M.W.

2002-01-01

Biowaste materials were evaluated as metal ion adsorbents in aqueous medium. The biowaste used were black gram husk, wheat bran, sheesham (dalbergia sissoo) sawdust pea pod, rice husk and cotton and mustard seed cakes. All these biosorbents, except pea pod and rice husk, exhibited good adsorption potential for Cd, Pb, Cu, Zn and Ni. Black gram husk (bgh) was found to have the highest sorption capacity with 100, 99.4, 95.7, 98.2 and 93.1% removal of Cd, Pb, Cu, Zn and Ni, respectively. The metal ions adsorbed by bgh desorbed with 0.1 M HCl and the regenerated biosorbent was reused successfully for sorption of metal ions in the next cycle. Concentration of the tested metals achieved at equilibrium in the contaminated aqueous medium was well below the maximum limits recommended by UNEP for sewage discharge. The study indicates the potential of bgh as a new, inexpensive and efficient biosorbent for the treatment of water contaminated with heavy metals. (author)

Recent Advancements in Self-Healing Metallic Materials and Self-Healing Metal Matrix Composites

Science.gov (United States)

Kilicli, Volkan; Yan, Xiaojun; Salowitz, Nathan; Rohatgi, Pradeep K.

2018-04-01

Engineered self-healing materials inspired by natural biological organisms that can repair damage are receiving increasing interest in recent years. Most studies have been focused on self-healing polymers, concretes, and ceramics. Self-healing metallic materials pose challenges due to the high temperatures used in manufacturing and the chemistries involved. This article summarizes and evaluates the self-healing mechanisms used in metallic materials and reviews recent studies into self-healing in aluminum, zinc, and Sn-Bi alloys. Generalizations about the various classifications are drawn from the review highlighting major hurdles in the widespread practical application of metallic self-healing materials, as well as the potential directions for future studies.

Metal Matrix Composite Material by Direct Metal Deposition

Science.gov (United States)

Novichenko, D.; Marants, A.; Thivillon, L.; Bertrand, P. H.; Smurov, I.

Direct Metal Deposition (DMD) is a laser cladding process for producing a protective coating on the surface of a metallic part or manufacturing layer-by-layer parts in a single-step process. The objective of this work is to demonstrate the possibility to create carbide-reinforced metal matrix composite objects. Powders of steel 16NCD13 with different volume contents of titanium carbide are tested. On the base of statistical analysis, a laser cladding processing map is constructed. Relationships between the different content of titanium carbide in a powder mixture and the material microstructure are found. Mechanism of formation of various precipitated titanium carbides is investigated.

Carnot cycle for magnetic materials: The role of hysteresis

International Nuclear Information System (INIS)

Sasso, Carlo P.; Basso, Vittorio; LoBue, Martino; Bertotti, Giorgio

2006-01-01

The role of hysteresis in a refrigeration thermodynamic cycle involving ferromagnetic materials is discussed. A model allowing to calculate magnetization, entropy and entropy production in systems with hysteresis is used to compute a non-ideal Carnot cycle performed on a ferromagnetic material

Properties of structural materials in liquid metal environment. Proceedings

Energy Technology Data Exchange (ETDEWEB)

Borgstedt, H U [ed.

1991-12-15

The International Working Group on Fast Reactors (IWGFR) Specialists Meeting on Properties of Structural Materials in Liquid Metal Environment was held during June 18 to June 20, 1991, at the Nuclear Research Centre (Kernforschungszentrum) in Karlsruhe, Germany. The Specialists Meeting was divided into five technical sessions which addressed topics as follows: Creep-Rupture Behaviour of Structural Materials in Liquid Metal Environment; Behaviour of Materials in Liquid Metal Environments under Off-Normal Conditions;Fatigue and Creep-Fatigue of Structural Materials in Liquid Metal Environment; Crack Propagation in Liquid Sodium; and Conclusions and recommendations. Individual papers have been cataloged separately.

Superior Cycle Stability Performance of Quasi-Cuboidal CoV2O6 Microstructures as Electrode Material for Supercapacitors.

Science.gov (United States)

Wang, Yucheng; Chai, Hui; Dong, Hong; Xu, Jiayu; Jia, Dianzeng; Zhou, Wanyong

2016-10-12

In this study, a rapid, facile, and environment-friendly microwave-assisted method followed by annealing for synthesizing the quasi-cuboidal CoV 2 O 6 is developed. The as-prepared samples manifest high supercapacitor properties with a specific capacitance of 223 F g -1 , good rate capability, and superior cycle stability, retaining 123.3% capacitance when the number of cycles reaches 15,000 after determined by electrochemical tests. More importantly, the quasi-cuboidal CoV 2 O 6 for the first time is introduced into the supercapacitor as a kind of electrode material. The superior electrochemical performance of the quasi-cuboidal CoV 2 O 6 will render the metal vanadium oxides as new and attractive active material for promising application in supercapacitors.

Accumulation and biological cycling of heavy metal in four salt marsh species, from Tagus estuary (Portugal)

Energy Technology Data Exchange (ETDEWEB)

Duarte, B., E-mail: baduarte@fc.ul.p [Centro de Oceanografia, Instituto de Oceanografia, Campo Grande, 1749-1016 Lisboa (Portugal); Caetano, M. [INRB/IPIMAR - Instituto Nacional de Recursos Biologicos, Av. Brasilia, 1449-006 Lisboa (Portugal); Almeida, P.R. [Centro de Oceanografia, Instituto de Oceanografia, Campo Grande, 1749-1016 Lisboa (Portugal); Departamento de Biologia, Universidade de Evora, Largo dos Colegiais 2, 7004-516 Evora (Portugal); Vale, C. [INRB/IPIMAR - Instituto Nacional de Recursos Biologicos, Av. Brasilia, 1449-006 Lisboa (Portugal); Cacador, I. [Centro de Oceanografia, Instituto de Oceanografia, Campo Grande, 1749-1016 Lisboa (Portugal)

2010-05-15

Pools of Zn, Cu, Cd and Co in leaf, stem and root tissues of Sarcocornia fruticosa, Sarcocornia perennis, Halimione portulacoides and Spartina maritima were analyzed on a bimonthly basis, in a Tagus estuary salt marsh. All the major concentrations were found in the root tissues, being the concentrations in the aboveground organs neglectable for sediment budget proposes, as seen by the low root-aboveground translocation. Metal annual accumulation, root turnovers and cycling coefficients were also assessed. S. maritima showed the higher root turnovers and cycling coefficients for most of the analyzed metals, making this a phytostabilizer specie. By contrast the low root turnover, cycling coefficient and low root necromass generation makes S. perennis the most suitable specie for phytoremediation processes. Although the high amounts of metal return to the sediments, due to root senescence, salt marshes can still be considered sinks of heavy metals, cycling heavy metals mostly between sediment and root. - The efficiency of the phytoremediative processes and metal budgets are greatly influenced by the turnover periods and necromass generation.

Nuclear material production cycle vulnerability analysis

International Nuclear Information System (INIS)

Bott, T.F.

1996-01-01

This paper discusses a method for rapidly and systematically identifying vulnerable equipment in a nuclear material or similar production process and ranking that equipment according to its attractiveness to a malevolent attacker. A multistep approach was used in the analysis. First, the entire production cycle was modeled as a flow diagram. This flow diagram was analyzed using graph theoretical methods to identify processes in the production cycle and their locations. Models of processes that were judged to be particularly vulnerable based on the cycle analysis then were developed in greater detail to identify equipment in that process that is vulnerable to intentional damage

Use of polyethylene glycol for the improvement of the cycling stability of bischofite as thermal energy storage material

International Nuclear Information System (INIS)

Gutierrez, Andrea; Ushak, Svetlana; Galleguillos, Hector; Fernandez, Angel; Cabeza, Luisa F.; Grágeda, Mario

2015-01-01

Highlights: • Bischofite as phase change material for TES is studied. • Thermophysical properties of bischofite mixtures with PEG were determined. • The aim was to improve the cycling stability of bischofite. • The heating and cooling during 30 cycles were measured. • The most stable sample was bischofite + 5% PEG 2 000. - Abstract: Bischofite is a by-product of the non-metallic mining industry. It has been evaluated as phase change material in thermal energy storage, but it shows little cycling stability, therefore in this paper the mixture of bischofite with an additive was studied. Since polyethylene glycol (PEG) is a PCM itself, in this paper PEG (with different molecular weights) is used as additive in a PCM (bischofite) to improve its thermal behaviour. Results show that adding 5% PEG 2 000 to bischofite gives a more cycling stable PCM without affecting its melting temperature neither decreasing significantly its heat of fusion. This research shows that mixing an inorganic PCM with an organic additive can be a good option to improve the thermal performance of the PCM

Metallic Sn-Based Anode Materials: Application in High-Performance Lithium-Ion and Sodium-Ion Batteries.

Science.gov (United States)

Ying, Hangjun; Han, Wei-Qiang

2017-11-01

With the fast-growing demand for green and safe energy sources, rechargeable ion batteries have gradually occupied the major current market of energy storage devices due to their advantages of high capacities, long cycling life, superior rate ability, and so on. Metallic Sn-based anodes are perceived as one of the most promising alternatives to the conventional graphite anode and have attracted great attention due to the high theoretical capacities of Sn in both lithium-ion batteries (LIBs) (994 mA h g -1 ) and sodium-ion batteries (847 mA h g -1 ). Though Sony has used Sn-Co-C nanocomposites as its commercial LIB anodes, to develop even better batteries using metallic Sn-based anodes there are still two main obstacles that must be overcome: poor cycling stability and low coulombic efficiency. In this review, the latest and most outstanding developments in metallic Sn-based anodes for LIBs and SIBs are summarized. And it covers the modification strategies including size control, alloying, and structure design to effectually improve the electrochemical properties. The superiorities and limitations are analyzed and discussed, aiming to provide an in-depth understanding of the theoretical works and practical developments of metallic Sn-based anode materials.

Metal- and Carbon-Based Materials as Heterogeneous Electrocatalysts for CO₂ Reduction.

Science.gov (United States)

Khan, Azam; Ullah, Haseeb; Nasir, Jamal Abdul; Shuda, Suzanne; Chen, Wei; Khan, M Abdullah

2018-05-01

Climate change caused by continuous rising level of CO2 and the depletion of fossil fuels reserves has made it highly desirable to electrochemically convert CO2 into fuels and commodity chemicals. Implementing this approach will close the carbon cycle by recycling CO2 providing a sustainable way to store energy in the chemical bonds of portable molecular fuels. In order to make the process commercially viable, the challenge of slow kinetics of CO2 electroreduction and low energy efficiency of the process need to be addressed. To this end, this review summarizes the progress made in the past few years in the development of heterogeneous electrocatalysts with a focus on nanostructured material for CO2 reduction to CO, HCOOH/HCOO-, CH2O, CH4, H2C2O4/HC2O-4, C2H4, CH3OH, CH3CH2OH, etc. The electrocatalysts presented here are classified into metals, metal alloys, metal oxides, metal chalcogenides and carbon based materials on the basis of their elemental composition, whose performance is discussed in light of catalyst activity, product selectivity, Faradaic efficiency (FE), catalytic durability and in selected cases mechanism of CO2 electroreduction. The effect of particle size, morphology and solution-electrolyte type and composition on the catalyst property/activity is also discussed and finally some strategies are proposed for the development of CO2 electroreduction catalysts. The aim of this article is to review the recent advances in the field of CO2 electroreduction in order to further facilitate research and development in this area.

Concurrent material-fabrication optimization of metal-matrix laminates under thermo-mechanical loading

Science.gov (United States)

Saravanos, D. A.; Morel, M. R.; Chamis, C. C.

1991-01-01

A methodology is developed to tailor fabrication and material parameters of metal-matrix laminates for maximum loading capacity under thermomechanical loads. The stresses during the thermomechanical response are minimized subject to failure constrains and bounds on the laminate properties. The thermomechanical response of the laminate is simulated using nonlinear composite mechanics. Evaluations of the method on a graphite/copper symmetric cross-ply laminate were performed. The cross-ply laminate required different optimum fabrication procedures than a unidirectional composite. Also, the consideration of the thermomechanical cycle had a significant effect on the predicted optimal process.

Proposed industrial recovered materials utilization targets for the metals and metal products industry

Energy Technology Data Exchange (ETDEWEB)

None

1979-05-01

Set targets for increased utilization of energy-saving recovered materials in the metals and metal products industries (ferrous, aluminium, copper, zinc, and lead) are discussed. Data preparation and methodology development and analysis of the technological and economic factors in order to prepare draft targets for the use of recovered materials are covered. Chapter 2 provides an introductory discussion of the factors that affect the recovery and reuse of secondary materials and the competition between the primary and secondary metals industries. Chapter 3 presents general profiles for the major industrial segments comprising SIC 33, including industry structure, process technology, materials and recycling flow, and future trends for the 5 industries: ferrous, aluminium, copper, zinc, and lead. Chapter 4 presents the evaluation of recycling targets for those industries. (MCW)

Low cycle fatigue lifetime of HIP bonded Bi-metallic first wall structures of fusion reactors

Energy Technology Data Exchange (ETDEWEB)

Hatano, Toshihisa; Sato, Satoshi; Furuya, Kazuyuki; Kuroda, Toshimasa; Enoeda, Mikio; Takatsu, Hideyuki [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment; Hashimoto, Toshiyuki; Kitamura, Kazunori

1998-10-01

A HIP bonded bi-metallic panel composed of a dispersion strengthened copper (DSCu) layer and type 316L stainless steel (SS316L) cooling pipes is the reference design of the ITER first wall. To examine the fatigue lifetime of the first wall panel under cyclic mechanical loads, low cycle fatigue tests of HIP bonded bi-metallic specimens made of SS316L and DSCu were conducted with the stress ratio of -1.0 and five nominal strain range conditions ranging from 0.2 to 1.0%. Elasto-plastic analysis has also been conducted to evaluate local strain ranges under the nominal strains applied. Initial cracks were observed at the inner surface of the SS316L cooling pipes for all of the specimens tested, which was confirmed by the elasto-plastic analysis that the maximum strains of the test specimens were developed at the same locations. It was found that the HIP bonded bi-metallic test specimens had a fatigue lifetime longer than that of the SS316L raw material obtained by round bar specimens. Similarly, the fatigue lifetime of the DSCu/SS316L HIP interface was also longer than the round bar test results for the HIP joints. From these results, it has been confirmed that the bi-metallic first wall panel with built-in cooling pipes made by HIP bonding has a sufficient fatigue lifetime in comparison with the raw fatigue data of the materials, which also suggests that the fatigue lifetime evaluation has an adequate margin against fracture if it follows the design fatigue curve based on the material fatigue data. (author)

Solid state cathode materials for secondary magnesium-ion batteries that are compatible with magnesium metal anodes in water-free electrolyte

International Nuclear Information System (INIS)

Crowe, Adam J.; Bartlett, Bart M.

2016-01-01

With high elemental abundance, large volumetric capacity, and dendrite-free metal deposition, magnesium metal anodes offer promise in beyond-lithium-ion batteries. However, the increased charge density associated with the divalent magnesium-ion (Mg 2+ ), relative to lithium-ion (Li + ) hinders the ion-insertion and extraction processes within many materials and structures known for lithium-ion cathodes. As a result, many recent investigations incorporate known amounts of water within the electrolyte to provide temporary solvation of the Mg 2+ , improving diffusion kinetics. Unfortunately with the addition of water, compatibility with magnesium metal anodes disappears due to forming an ion-insulating passivating layer. In this short review, recent advances in solid state cathode materials for rechargeable magnesium-ion batteries are highlighted, with a focus on cathode materials that do not require water contaminated electrolyte solutions for ion insertion and extraction processes. - Graphical abstract: In this short review, we present candidate materials for reversible Mg-battery cathodes that are compatible with magnesium metal in water-free electrolytes. The data suggest that soft, polarizable anions are required for reversible cycling.

Recycling of nonferrous metals from waste materials

Energy Technology Data Exchange (ETDEWEB)

Urban, A

1982-02-01

Recycling of metals was one of the 9 central subjects of the international symposium on 'Materials and Energy from Refuse', held in Antwerpen on October 20 to 22, 1981. Six of 65 poster sessions papers were on metal recycling; four of them discussed the recycling of nonferrous metals.

Ab Initio Studies of Metal Hexaboride Materials

Science.gov (United States)

Schmidt, Kevin M.

Metal hexaborides are refractory ceramics with several qualities relevant to materials design, such as low work functions, high hardness, low thermal expansion coefficients, and high melting points, among many other properties of interest for industrial applications. Thermal and mechanical stability is a common feature provided by the covalently-bonded network boron atoms, and electronic properties can vary significantly with the resident metal. While these materials are currently employed as electron emitters and abrasives, promising uses of these materials also include catalytic applications for chemical dissociation reactions of various molecules such as hydrogen, water and carbon monoxide, for example. However, these extensions require a thorough understanding of particular mechanical and electronic properties. This dissertation is a collection of studies focused on understanding the behavior of metal hexaboride materials using computational modeling methods to investigate materials properties of these from both classical and quantum mechanical points of view. Classical modeling is performed using molecular dynamics methods with interatomic potentials obtained from density functional theory (DFT) calculations. Atomic mean-square displacements from the quasi-harmonic approximation and lattice energetic data are produced with DFT for developing the potentials. A generalized method was also developed for the inversion of cohesive energy curves of crystalline materials; pairwise interatomic potentials are extracted using detailed geometrical descriptions of the atomic interactions and a list of atomic displacements and degeneracies. The surface structure of metal hexaborides is studied with DFT using several model geometries to describe the terminal cation layouts, and these provide a basis for further studies on metal hexaboride interactions with hydrogen. The surface electronic structure calculations show that segregated regions of metal and boron

Charge transport in metal oxide nanocrystal-based materials

Science.gov (United States)

Runnerstrom, Evan Lars

There is probably no class of materials more varied, more widely used, or more ubiquitous than metal oxides. Depending on their composition, metal oxides can exhibit almost any number of properties. Of particular interest are the ways in which charge is transported in metal oxides: devices such as displays, touch screens, and smart windows rely on the ability of certain metal oxides to conduct electricity while maintaining visible transparency. Smart windows, fuel cells, and other electrochemical devices additionally rely on efficient transport of ionic charge in and around metal oxides. Colloidal synthesis has enabled metal oxide nanocrystals to emerge as a relatively new but highly tunable class of materials. Certain metal oxide nanocrystals, particularly highly doped metal oxides, have been enjoying rapid development in the last decade. As in myriad other materials systems, structure dictates the properties of metal oxide nanocrystals, but a full understanding of how nanocrystal synthesis, the processing of nanocrystal-based materials, and the structure of nanocrystals relate to the resulting properties of nanocrystal-based materials is still nascent. Gaining a fundamental understanding of and control over these structure-property relationships is crucial to developing a holistic understanding of metal oxide nanocrystals. The unique ability to tune metal oxide nanocrystals by changing composition through the introduction of dopants or by changing size and shape affords a way to study the interplay between structure, processing, and properties. This overall goal of this work is to chemically synthesize colloidal metal oxide nanocrystals, process them into useful materials, characterize charge transport in materials based on colloidal metal oxide nanocrystals, and develop ways to manipulate charge transport. In particular, this dissertation characterizes how the charge transport properties of metal oxide nanocrystal-based materials depend on their processing and

Metal-Organic Framework-Derived Materials for Sodium Energy Storage.

Science.gov (United States)

Zou, Guoqiang; Hou, Hongshuai; Ge, Peng; Huang, Zhaodong; Zhao, Ganggang; Yin, Dulin; Ji, Xiaobo

2018-01-01

Recently, sodium-ion batteries (SIBs) are extensively explored and are regarded as one of the most promising alternatives to lithium-ion batteries for electrochemical energy conversion and storage, owing to the abundant raw material resources, low cost, and similar electrochemical behavior of elemental sodium compared to lithium. Metal-organic frameworks (MOFs) have attracted enormous attention due to their high surface areas, tunable structures, and diverse applications in drug delivery, gas storage, and catalysis. Recently, there has been an escalating interest in exploiting MOF-derived materials as anodes for sodium energy storage due to their fast mass transport resulting from their highly porous structures and relatively simple preparation methods originating from in situ thermal treatment processes. In this Review, the recent progress of the sodium-ion storage performances of MOF-derived materials, including MOF-derived porous carbons, metal oxides, metal oxide/carbon nanocomposites, and other materials (e.g., metal phosphides, metal sulfides, and metal selenides), as SIB anodes is systematically and completely presented and discussed. Moreover, the current challenges and perspectives of MOF-derived materials in electrochemical energy storage are discussed. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Surplus Cost Potential as a Life Cycle Impact Indicator for Metal Extraction

Directory of Open Access Journals (Sweden)

Marisa D.M. Vieira

2016-01-01

Full Text Available In the evaluation of product life cycles, methods to assess the increase in scarcity of resources are still under development. Indicators that can express the importance of an increase in scarcity of metals extracted include surplus ore produced, surplus energy required, and surplus costs in the mining and the milling stage. Particularly the quantification of surplus costs per unit of metal extracted as an indicator is still in an early stage of development. Here, we developed a method that quantifies the surplus cost potential of mining and milling activities per unit of metal extracted, fully accounting for mine-specific differences in costs. The surplus cost potential indicator is calculated as the average cost increase resulting from all future metal extractions, as quantified via cumulative cost-tonnage relationships. We tested the calculation procedure with 12 metals and platinum-group metals as a separate group. We found that the surplus costs range six orders of magnitude between the metals included, i.e., between $0.01–$0.02 (iron and $13,533–$17,098 (rhodium USD (year 2013 per kilogram of metal extracted. The choice of the reserve estimate (reserves vs. ultimate recoverable resource influenced the surplus costs only to a limited extent, i.e., between a factor of 0.7 and 3.2 for the metals included. Our results provide a good basis to regularly include surplus cost estimates as resource scarcity indicator in life cycle assessment.

Blender 2.6 cycles, materials and textures cookbook

CERN Document Server

Valenza, Enrico

2013-01-01

Written in a friendly, practical style this Cookbook deep-dives into a wide-array of techniques used to create realistic materials and textures.This book is perfect for you if you have used Blender before but are new to the impressive Cycles renderer. You should have some knowledge of the Blender interface, though this is not a strict requirement. If you want to create realistic, stunning materials and textures using Cycles, then this book is for you!

Effects of metals on life cycle parameters of the earthworm Eisenia fetida exposed to field-contaminated, metal-polluted soils

International Nuclear Information System (INIS)

Nahmani, Johanne; Hodson, Mark E.; Black, Stuart

2007-01-01

Two control and eight field-contaminated, metal-polluted soils were inoculated with Eisenia fetida (Savigny, 1826). Three, 7, 14, 21, 28 and 42 days after inoculation, earthworm survival, body weight, cocoon production and hatching rate were measured. Seventeen metals were analysed in E. fetida tissue, bulk soil and soil solution. Soil organic carbon content, texture, pH and cation exchange capacity were also measured. Cocoon production and hatching rate were more sensitive to adverse conditions than survival or weight change. Soil properties other than metal concentration impacted toxicity. The most toxic soils were organic-poor (1-10 g C kg -1 ), sandy soils (c. 74% sand), with intermediate metal concentrations (e.g. 7150-13,100 mg Pb kg -1 , 2970-53,400 mg Zn kg -1 ). Significant relationships between soil properties and the life cycle parameters were determined. The best coefficients of correlation were generally found for texture, pH, Ag, Cd, Mg, Pb, Tl, and Zn both singularly and in multivariate regressions. Studies that use metal-amended artificial soils are not useful to predict toxicity of field multi-contaminated soils. - Soil pH, organic carbon content and texture can exert a greater influence on earthworm life cycle parameters than soil metal concentrations at metal-contaminated sites

Effects of metals on life cycle parameters of the earthworm Eisenia fetida exposed to field-contaminated, metal-polluted soils

Energy Technology Data Exchange (ETDEWEB)

Nahmani, Johanne [Department of Soil Science, School of Human and Environmental Sciences, University of Reading, Whiteknights, Reading, Berkshire RG6 6DW (United Kingdom)]. E-mail: nahmani@univ-metz.fr; Hodson, Mark E. [Department of Soil Science, School of Human and Environmental Sciences, University of Reading, Whiteknights, Reading, Berkshire RG6 6DW (United Kingdom)]. E-mail: m.e.hodson@reading.ac.uk; Black, Stuart [Department of Archaeology, School of Human and Environmental Sciences, Whiteknights, University of Reading, Reading RG6 6DW (United Kingdom)

2007-09-15

Two control and eight field-contaminated, metal-polluted soils were inoculated with Eisenia fetida (Savigny, 1826). Three, 7, 14, 21, 28 and 42 days after inoculation, earthworm survival, body weight, cocoon production and hatching rate were measured. Seventeen metals were analysed in E. fetida tissue, bulk soil and soil solution. Soil organic carbon content, texture, pH and cation exchange capacity were also measured. Cocoon production and hatching rate were more sensitive to adverse conditions than survival or weight change. Soil properties other than metal concentration impacted toxicity. The most toxic soils were organic-poor (1-10 g C kg{sup -1}), sandy soils (c. 74% sand), with intermediate metal concentrations (e.g. 7150-13,100 mg Pb kg{sup -1}, 2970-53,400 mg Zn kg{sup -1}). Significant relationships between soil properties and the life cycle parameters were determined. The best coefficients of correlation were generally found for texture, pH, Ag, Cd, Mg, Pb, Tl, and Zn both singularly and in multivariate regressions. Studies that use metal-amended artificial soils are not useful to predict toxicity of field multi-contaminated soils. - Soil pH, organic carbon content and texture can exert a greater influence on earthworm life cycle parameters than soil metal concentrations at metal-contaminated sites.

Energy Approach-Based Simulation of Structural Materials High-Cycle Fatigue

Science.gov (United States)

Balayev, A. F.; Korolev, A. V.; Kochetkov, A. V.; Sklyarova, A. I.; Zakharov, O. V.

2016-02-01

The paper describes the mechanism of micro-cracks development in solid structural materials based on the theory of brittle fracture. A probability function of material cracks energy distribution is obtained using a probabilistic approach. The paper states energy conditions for cracks growth at material high-cycle loading. A formula allowing to calculate the amount of energy absorbed during the cracks growth is given. The paper proposes a high- cycle fatigue evaluation criterion allowing to determine the maximum permissible number of solid body loading cycles, at which micro-cracks start growing rapidly up to destruction.

Ceramic/metal and A15/metal superconducting composite materials exploiting the superconducting proximity effect and method of making the same

International Nuclear Information System (INIS)

Holcomb, M.J.

1999-01-01

A composite superconducting material made of coated particles of ceramic superconducting material and a metal matrix material is disclosed. The metal matrix material fills the regions between the coated particles. The coating material is a material that is chemically nonreactive with the ceramic. Preferably, it is silver. The coating serves to chemically insulate the ceramic from the metal matrix material. The metal matrix material is a metal that is susceptible to the superconducting proximity effect. Preferably, it is a NbTi alloy. The metal matrix material is induced to become superconducting by the superconducting proximity effect when the temperature of the material goes below the critical temperature of the ceramic. The material has the improved mechanical properties of the metal matrix material. Preferably, the material consists of approximately 10% NbTi, 90% coated ceramic particles (by volume). Certain aspects of the material and method will depend upon the particular ceramic superconductor employed. An alternative embodiment of the invention utilizes A15 compound superconducting particles in a metal matrix material which is preferably a NbTi alloy

Ceramic/metal and A15/metal superconducting composite materials exploiting the superconducting proximity effect and method of making the same

Science.gov (United States)

Holcomb, Matthew J.

1999-01-01

A composite superconducting material made of coated particles of ceramic superconducting material and a metal matrix material. The metal matrix material fills the regions between the coated particles. The coating material is a material that is chemically nonreactive with the ceramic. Preferably, it is silver. The coating serves to chemically insulate the ceramic from the metal matrix material. The metal matrix material is a metal that is susceptible to the superconducting proximity effect. Preferably, it is a NbTi alloy. The metal matrix material is induced to become superconducting by the superconducting proximity effect when the temperature of the material goes below the critical temperature of the ceramic. The material has the improved mechanical properties of the metal matrix material. Preferably, the material consists of approximately 10% NbTi, 90% coated ceramic particles (by volume). Certain aspects of the material and method will depend upon the particular ceramic superconductor employed. An alternative embodiment of the invention utilizes A15 compound superconducting particles in a metal matrix material which is preferably a NbTi alloy.

Fabrication of ultrahigh density metal-cell-metal crossbar memory devices with only two cycles of lithography and dry-etch procedures

KAUST Repository

Zong, Baoyu; Goh, J. Y.; Guo, Zaibing; Luo, Ping; Wang, Chenchen; Qiu, Jinjun; Ho, Pin; Chen, Yunjie; Zhang, Mingsheng; Han, Guchang

2013-01-01

A novel approach to the fabrication of metal-cell-metal trilayer memory devices was demonstrated by using only two cycles of lithography and dry-etch procedures. The fabricated ultrahigh density crossbar devices can be scaled down to ≤70 nm in half

Comparative alternative materials assessment to screen toxicity hazards in the life cycle of CIGS thin film photovoltaics

International Nuclear Information System (INIS)

Eisenberg, Daniel A.; Yu, Mengjing; Lam, Carl W.; Ogunseitan, Oladele A.; Schoenung, Julie M.

2013-01-01

Highlights: • Comparative alternatives assessment of thin film manufacturing technologies. • Development of chemical alternatives assessment in a life cycle context. • Screening of manufacturing and solar cell hazardous substances simultaneously. -- Abstract: Copper–indium–gallium–selenium–sulfide (CIGS) thin film photovoltaics are increasingly penetrating the market supply for consumer solar panels. Although CIGS is attractive for producing less greenhouse gas emissions than fossil-fuel based energy sources, CIGS manufacturing processes and solar cell devices use hazardous materials that should be carefully considered in evaluating and comparing net environmental benefits of energy products. Through this research, we present a case study on the toxicity hazards associated with alternative materials selection for CIGS manufacturing. We applied two numeric models, The Green Screen for Safer Chemicals™ and the Toxic Potential Indicator. To improve the sensitivity of the model outputs, we developed a novel, life cycle thinking based hazard assessment method that facilitates the projection of hazards throughout material life cycles. Our results show that the least hazardous CIGS solar cell device and manufacturing protocol consist of a titanium substrate, molybdenum metal back electrode, CuInS 2 p-type absorber deposited by spray pyrolysis, ZnS buffer deposited by spray ion layer gas reduction, ZnO:Ga transparent conducting oxide (TCO) deposited by sputtering, and the encapsulant polydimethylsiloxane

Monitoring Low-Cycle Fatigue Material-Degradation by Ultrasonic Methods

Directory of Open Access Journals (Sweden)

R. Himawan

2010-08-01

Full Text Available Any system consisting of structural material often undergoes fatigue, which is caused by dynamic load cycle. As a structural system, nuclear power plant is very likely to have low-cycle fatigue at many of its components. Taking into account the importance of monitoring low-cycle fatigue on structural components to prevent them from getting failure, the authors have conducted a work to monitor material degradation caused by low-cycle fatigue by using ultrasonic method. An alloy of Cu-40Zn was used as a test specimen. Ultrasonic water immersion procedure was employed in this ultrasonic test. The probe used is a focusing type and has frequency as high as 15 MHz. The specimen area tested is in the middle part divided into 14 points × 23 points. The results, which were frequency spectrums, were analyzed using two parameters: frequency spectrum peak intensity and attenuation function gradient. The analysis indicates that peak intensity increases at the beginning of load cycle and then decreases. Meanwhile, gradient of attenuation function is lower at the beginning of fatigue process, and then consistently gets higher. It concludes that low-fatigue material degradation can be monitored by using ultrasonic method.

Fusion fuel cycle: material requirements and potential effluents

International Nuclear Information System (INIS)

Teofilo, V.L.; Bickford, W.E.; Long, L.W.; Price, B.A.; Mellinger, P.J.; Willingham, C.E.; Young, J.K.

1980-10-01

Environmental effluents that may be associated with the fusion fuel cycle are identified. Existing standards for controlling their release are summarized and anticipated regulatory changes are identified. The ability of existing and planned environmental control technology to limit effluent releases to acceptable levels is evaluated. Reference tokamak fusion system concepts are described and the principal materials required of the associated fuel cycle are analyzed. These materials include the fusion fuels deuterium and tritium; helium, which is used as a coolant for both the blanket and superconducting magnets; lithium and beryllium used in the blanket; and niobium used in the magnets. The chemical and physical processes used to prepare these materials are also described

Fusion fuel cycle: material requirements and potential effluents

Energy Technology Data Exchange (ETDEWEB)

Teofilo, V.L.; Bickford, W.E.; Long, L.W.; Price, B.A.; Mellinger, P.J.; Willingham, C.E.; Young, J.K.

1980-10-01

Environmental effluents that may be associated with the fusion fuel cycle are identified. Existing standards for controlling their release are summarized and anticipated regulatory changes are identified. The ability of existing and planned environmental control technology to limit effluent releases to acceptable levels is evaluated. Reference tokamak fusion system concepts are described and the principal materials required of the associated fuel cycle are analyzed. These materials include the fusion fuels deuterium and tritium; helium, which is used as a coolant for both the blanket and superconducting magnets; lithium and beryllium used in the blanket; and niobium used in the magnets. The chemical and physical processes used to prepare these materials are also described.

Heat-processing method and facility for helium-containing metal material

International Nuclear Information System (INIS)

Kato, Takahiko; Kodama, Hideyo; Matsumoto, Toshimi; Aono, Yasuhisa; Nagata, Tetsuya; Hattori, Shigeo; Kaneda, Jun-ya; Ono, Shigeki.

1996-01-01

Electric current is supplied to an objective portion of a He-containing metal material to be applied with heat processing without causing melting, to decrease the He content of the portion. Subsequently, the defect portion of the tissues of the He-containing metal is modified by heating the portion with melting. Since electric current can be supplied to the metal material in a state where the metal material is heated and the temperature thereof is elevated, an effect of further reducing the He content can be obtained. Further, if the current supply and/or the heating relative to the metal material is performed in a vacuum or inert gas atmosphere, an effect of reducing the degradation of the surface of the objective portion to be supplied with electric current can be obtained. (T.M.)

Performance ratio hardness characteristics polystyrene-metal composite materials

International Nuclear Information System (INIS)

Klepikov, V.F.; Prokhorenko, E.M.; Lytvynenko, V.V.; Zakharchenko, A.A.; Hazhmuradov, M.A.

2015-01-01

The methods of measuring the hardness of layered polystyrene-metallic composite materials. It is proposed to use powder-like tungsten and powder-like steel as radiation-protective layer. A measurement of the hardness of composites of different composition, and given its dependence on the particle size and their form. The possibility of increasing the hardness of the composites reinforced with metallic additives. Radiation-protective characteristics were calculated for the studied species of composite materials. Influence of the quantitative composition of the metal components is studied on the change of the absorbed dose of gamma radiation

Corrosion of metal materials embedded in concrete

International Nuclear Information System (INIS)

Duffo, G.S.; Farina, S.B.; Schulz, F.M.

2010-01-01

Carbon steel is the material most frequently used to strengthen reinforced concrete structures; however, stainless steel and galvanized steel reinforcements are also used in construction concretes; and they are not often used in Latin America. Meanwhile, there are other metals that are embedded in the concrete forming part of the openings (aluminum) or in tubing systems (copper and lead). The use of concrete as a cementing material is also useful for immobilizing wastes, such as for example those generated by the nuclear industry. There is a great deal of research and development on the corrosion of steel reinforcements, but the same is not true for the behavior of other metals embedded in concrete and that also undergo corrosive processes. This work aims to study the corrosion of different metals: copper, lead, aluminum, zinc, stainless steel and carbon steel; embedded in concrete with and without the presence of aggressive species for the metal materials. Test pieces were made of mortar containing rods of different materials for testing, and with chlorides added in concentrations of 0; 0.3 % and 1% (mass of chloride per mass of cement). The test pieces were exposed to different conditions; laboratory environment with a relative humidity (RH) of 45%, a controlled atmosphere with 98% RH and submerged in a solution of 3.5% NaCl. The susceptibility to corrosion of the different metals was evaluated using techniques to monitor the corrosion potential, the resistivity of the mortar and the polarization resistance (PR). The rods were weighed before being placed inside the test pieces to later determine the loss of weight generated by the corrosion process. Polarization curves for the metals were also traced in a simulated pore solution (SPS) and in SPS with added chloride. The results obtained to date show that, of all the metals analyzed, aluminum is the most susceptible to corrosion, and that the test specimens with 0% and 1% of chloride exposed to the laboratory

High power densities from high-temperature material interactions. [in thermionic energy conversion and metallic fluid heat pipes

Science.gov (United States)

Morris, J. F.

1981-01-01

Thermionic energy conversion (TEC) and metallic-fluid heat pipes (MFHPs), offering unique advantages in terrestrial and space energy processing by virtue of operating on working-fluid vaporization/condensation cycles that accept great thermal power densities at high temperatures, share complex materials problems. Simplified equations are presented that verify and solve such problems, suggesting the possibility of cost-effective applications in the near term for TEC and MFHP devices. Among the problems discussed are: the limitation of alkali-metal corrosion, protection against hot external gases, external and internal vaporization, interfacial reactions and diffusion, expansion coefficient matching, and creep deformation.

Investigation of Friction Behaviors of Brake Shoe Materials using Metallic Filler

Directory of Open Access Journals (Sweden)

E. Surojo

2015-12-01

Full Text Available Some vehicles use brake shoe made from semi-metallic materials. Semi-metallic brake shoes are made from a combination of metallic and non-metallic materials. Metallic particles are added in the formulation of brake shoe material to improve composites characteristics. In this paper, friction behaviors of brake shoe material using metallic filler were investigated. Machining chips of cast iron and copper wire of electric motor used were incorporated in composite as metallic fillers with amount 0, 2, and 4 vol. %. Friction testing was performed to measure coefficient of friction by pressing surface specimen against the surface of rotating disc. The results show that cast iron chip and Cu short wire have effect on increasing coefficient of friction of brake shoe material. They form contact plateau at contact surface. At contact surface, the Cu short wires which have parallel orientation to the sliding contact were susceptible to detach from the matrix.

Hand Book of Metal Material Contrast

International Nuclear Information System (INIS)

Park, Yeong Hui

1989-06-01

This book first gives descriptions of using of this hand book and contents. It tells of steel such as bar steel, section steel, and steel sheet which are steel for general structure and steel for pressure vessel, a steel pipe, carbon steel for machine structure and alloy steel, steel for special things, stainless steel, heat resisting steel, tool steel, spring steel, forging, steel casting, nonferrous metal such as aluminium and aluminium alloy, casting, list of similar steel per metal, list of steel like ASTM, AISI per number, and list of collecting standard per metal material.

Compatibility of materials with liquid metal targets for SNS

International Nuclear Information System (INIS)

DiStefano, J.R.; Pawel, S.J.; DeVan, J.H.

1996-01-01

Several heavy liquid metals are candidates as the target in a spallation neutron source: Hg, Pb, Bi, and Pb-Bi eutectic. Systems with these liquid metals have been used in the past and a data-base on compatibility already exists. Two major compatibility issues have been identified when selecting a container material for these liquid metals: temperature gradient mass transfer and liquid metal embrittlement or LME. Temperature gradient mass transfer refers to dissolution of material from the high temperature portions of a system and its deposition in the lower temperature areas. Solution and deposition rate constants along with temperature, ΔT, and velocity are usually the most important parameters. For most candidate materials mass transfer corrosion has been found to be proportionately worse in Bi compared with Hg and Pb. For temperatures to ∼550 degrees C, ferritic/martensitic steels have been satisfactory in Pb or Hg systems and the maximum temperature can be extended to ∼650 degrees C with additions of inhibitors to the liquid metal, e.g. Mg, Ti, Zr. Above ∼600 degrees C, austenitic stainless steels have been reported to be unsatisfactory, largely because of the mass transfer of nickel. Blockage of flow from deposition of material is usually the life-limiting effect of this type of corrosion. However, mass transfer corrosion at lower temperatures has not been studied. At low temperatures (usually < 150 degrees C), LME has been reported for some liquid metal/container alloy combinations. Liquid metal embrittlement, like hydrogen embrittlement, results in brittle fracture of a normally ductile material

Advances in nuclear fuel cycle materials and concepts. Vol. 1

Energy Technology Data Exchange (ETDEWEB)

El-Sayed, A A [Materials Division, Nuclear Research Centre, Atomic Energy Authority, Cairo (Egypt)

1996-03-01

This presentation gives an overview of the new trends in the materials used in various steps of the nuclear fuel cycle. This will cover fuels for various types of reactors (PWRs, HTRs, ... etc.) cladding materials, control rod materials, reactor structural materials, as well as materials used in the back end of the fuel cycle. Problems associated with corrosion of fuel cladding materials as well as those in control rod materials (B{sub 4} C swelling...etc.), and approaches for combating these influences are reviewed. For the case of reactor pressure vessel materials issues related to the influences of alloy composition, design approaches including the use of more forged parts and minimizing, as for as possible, longitudinal welds especially in the central region, are discussed. Furthermore the application of techniques for recovery of pre-irradiation mechanical properties of PVS components is also covered. New candidate materials for the construction of high level waste containers including modified types of stainless steel (high Ni and high MO), nickel-base alloys and titanium alloys are also detailed. Finally, nuclear fuel cycle concepts involving plutonium and actinides recycling shall be reviewed. 28 figs., 6 tabs.

Advances in nuclear fuel cycle materials and concepts. Vol. 1

International Nuclear Information System (INIS)

El-Sayed, A.A.

1996-01-01

This presentation gives an overview of the new trends in the materials used in various steps of the nuclear fuel cycle. This will cover fuels for various types of reactors (PWRs, HTRs, ... etc.) cladding materials, control rod materials, reactor structural materials, as well as materials used in the back end of the fuel cycle. Problems associated with corrosion of fuel cladding materials as well as those in control rod materials (B 4 C swelling...etc.), and approaches for combating these influences are reviewed. For the case of reactor pressure vessel materials issues related to the influences of alloy composition, design approaches including the use of more forged parts and minimizing, as for as possible, longitudinal welds especially in the central region, are discussed. Furthermore the application of techniques for recovery of pre-irradiation mechanical properties of PVS components is also covered. New candidate materials for the construction of high level waste containers including modified types of stainless steel (high Ni and high MO), nickel-base alloys and titanium alloys are also detailed. Finally, nuclear fuel cycle concepts involving plutonium and actinides recycling shall be reviewed. 28 figs., 6 tabs

Fracture resistance of metal-free composite crowns-effects of fiber reinforcement, thermal cycling, and cementation technique.

Science.gov (United States)

Lehmann, Franziska; Eickemeyer, Grit; Rammelsberg, Peter

2004-09-01

The improved mechanical properties of contemporary composites have resulted in their extensive use for the restoration of posterior teeth. However, the influence of fiber reinforcement, cementation technique, and physical stress on the fracture resistance of metal-free crowns is unknown. This in vitro study evaluated the effect of fiber reinforcement, physical stress, and cementation methods on the fracture resistance of posterior metal-free Sinfony crowns. Ninety-six extracted human third molars received a standardized tooth preparation: 0.5-mm chamfer preparation and occlusal reduction of 1.3 to 1.5 mm. Sinfony (nonreinforced crowns, n=48) and Sinfony-Vectris (reinforced crowns, n=48) crowns restoring original tooth contour were prepared. Twenty-four specimens of each crown type were cemented, using either glass ionomer cement (GIC) or resin cement. Thirty-two crowns (one third) were stored in humidity for 48 hours. Another third was exposed to 10,000 thermal cycles (TC) between 5 degrees C and 55 degrees C. The remaining third was treated with thermal cycling and mechanical loading (TCML), consisting of 1.2 million axial loads of 50 N. The artificial crowns were then vertically loaded with a steel sphere until failure occurred. Significant differences in fracture resistance (N) between experimental groups were assessed by nonparametric Mann-Whitney U-test (alpha=.05). Fifty percent of the Sinfony and Sinfony-Vectris crowns cemented with glass ionomer cement loosened after thermal cycling. Thermal cycling resulted in a significant reduction in the mean fracture resistance for Sinfony crowns cemented with GIC, from 2037 N to 1282 N (P=.004). Additional fatigue produced no further effects. Fiber reinforcement significantly increased fracture resistance, from 1555 N to 2326 N (P=.001). The minimal fracture resistance was above 600 N for all combinations of material, cement and loading. Fracture resistance of metal-free Sinfony crowns was significantly increased by

Life cycle assessment of polysaccharide materials: a review

NARCIS (Netherlands)

Shen, L.|info:eu-repo/dai/nl/310872022; Patel, M.K.|info:eu-repo/dai/nl/18988097X

2008-01-01

Apart from conventional uses of polysaccharide materials, such as food, clothing, paper packaging and construction, new polysaccharide products and materials have been developed. This paper reviews life cycle assessment (LCA) studies in order to gain insight of the environmental profiles of

Flop casting of nuclear materials for advanced fuel cycle research - 5247

International Nuclear Information System (INIS)

Swift, A.J.; Koury, D.J.; Czerwinski, K.R.; Vollmer, J.M.

2015-01-01

Full text of publication follows. Next generation fast reactor designs of nuclear reactors utilizing metallic fuel are being developed as an alternative fuel cycle option in an effort to reduce carbon emissions. Metallic fuel systems are attractive because of their high thermal conductivity, fissile atom density, and inherent safety. Metallic fuel systems are also being investigated because of their potential to reach high burnups. The increased targeted burnups for metallic fuels lead to higher concentrations of actinides, lanthanides, and other fission products, which alter the fuel properties and impact the performance of the fuel. Before designs can be implemented, the fission product concentrations must be studied at variable fuel geometries and stages of fuel burnup. Arc flop casting serves as a viable option for casting alloys as the molds can be tailored to fit design specific requirements while cutting costs in time-consuming machining. Arc casting is done as the final preparation step in a small arc furnace with an argon or 5% hydrogen-argon atmosphere after the sample has been subsequently melted, overturned, and re-melted. The flop casting mold is then fitted to the chamber as needed and the previously prepared sample is quickly hit with a high current arc causing the molten metal to fill the copper mold. The U-Zr-Pu system will serve as the basis for this research as it has been extensively studied since the 1950 years, although flop casting can be adapted to any metallic fuel system. Multiple U-Zr-Pu with varying fission product concentrations alloys, Technetium metal, and Plutonium alloys have been flop cast based on burnup calculations. Prepared samples were cast using different molds and dimensions, then characterized by Scanning Electron Microscopy, X-ray diffraction, and Thermogravimetric Analysis. The goal of this research is to test and develop flop casting techniques for the production of metallic fuel alloys applicable for various stages and

All-Metallic Vertical Transistors Based on Stacked Dirac Materials

OpenAIRE

Wang, Yangyang; Ni, Zeyuan; Liu, Qihang; Quhe, Ruge; Zheng, Jiaxin; Ye, Meng; Yu, Dapeng; Shi, Junjie; Yang, Jinbo; Lu, Jing

2014-01-01

It is an ongoing pursuit to use metal as a channel material in a field effect transistor. All metallic transistor can be fabricated from pristine semimetallic Dirac materials (such as graphene, silicene, and germanene), but the on/off current ratio is very low. In a vertical heterostructure composed by two Dirac materials, the Dirac cones of the two materials survive the weak interlayer van der Waals interaction based on density functional theory method, and electron transport from the Dirac ...

Effect of Thermal Cycling on the Tensile Behavior of CF/AL Fiber Metal Laminates

Directory of Open Access Journals (Sweden)

Muhammad Farhan Noor

2017-09-01

Full Text Available The objective of this research work was to estimate the effect of thermal cycling on the tensile behavior of CARALL composites. Fiber metal laminates (FMLs, based on 2D woven carbon fabric and 2024-T3 Alclad aluminum alloy sheet, was manufactured by pressure molding technique followed by hand layup method. Before fabrication, aluminum sheets were anodized with phosphoric acid to produce micro porous alumina layer on surface. This micro-porous layer is beneficial to produce strong bonding between metal and fiber surfaces in FMLs. The effect of thermal cycling (-65 to +70ºC on the tensile behavior of Cf/Al based FML was studied. Tensile strength was increased after 10 thermal cycles, but it was slightly decreased to some extent after 30, and 50 thermal cycles. Tensile modulus also shown the similar behavior as that of tensile strength.

Hierarchical structured graphene/metal oxide/porous carbon composites as anode materials for lithium-ion batteries

International Nuclear Information System (INIS)

Guo, Rong; Yue, Wenbo; Ren, Yu; Zhou, Wuzong

2016-01-01

Highlights: • CeO 2 and Co 3 O 4 nanoparticles display different behavior within CMK-3. • CMK-3-CeO 2 and Co 3 O 4 show various electrochemical properties • CMK-3-CeO 2 and Co 3 O 4 are further wrapped by graphene nanosheets. • Graphene-encapsulated composites show better electrochemical performances. - Abstract: As a novel anode material for lithium-ion batteries, CeO 2 displays imperceptible volumetric and morphological changes during the lithium insertion and extraction processes, and thereby exhibits good cycling stability. However, the low theoretical capacity and poor electronic conductivity of CeO 2 hinder its practical application. In contrast, Co 3 O 4 possesses high theoretical capacity, but undergoes huge volume change during cycling. To overcome these issues, CeO 2 and Co 3 O 4 nanoparticles are formed inside the pores of CMK-3 and display various electrochemical behaviors due to the different morphological structures of CeO 2 and Co 3 O 4 within CMK-3. Moreover, the graphene/metal oxide/CMK-3 composites with a hierarchical structure are then prepared and exhibit better electrochemical performances than metal oxides with or without CMK-3. This novel synthesis strategy is hopefully employed in the electrode materials design for Li-ion batteries or other energy conversion and storage devices.

Inorganic and Metallic Nanotubular Materials Recent Technologies and Applications

CERN Document Server

Kijima, Tsuyoshi

2010-01-01

This book describes the synthesis, characterization and applications of inorganic and metallic nanotubular materials. It cover a wide variety of nanotubular materials excluding carbon nanotubes, ranging from metal oxides, sulfides and nitrides such as titanium oxide, tungsten sulfide, and boron nitride, as well as platinum and other noble-metals to unique nanotubes consisting of water, graphene or fullerene. Based on their structural and compositional characteristics, these nanotubular materials are of importance for their potential applications in electronic devices, photocatalysts, dye-sensitized solar cells, nanothermometers, electrodes for fuel cells and batteries, sensors, and reinforcing fillers for plastics, among others. Such materials are also having a great impact on future developments, including renewable-energy sources as well as highly efficient energy-conversion and energy-saving technologies. This book will be of particular interest to experts in the fields of nanotechnology, material science ...

Preparation and electrochemical properties of core-shell carbon coated Mn–Sn complex metal oxide as anode materials for lithium-ion batteries

Energy Technology Data Exchange (ETDEWEB)

Zhang, Ruixue [Key Laboratory of Lithium Battery Materials of Jiangsu Province, Institute of chemical power sources, Soochow University, Suzhou 215006 (China); Fang, Guoqing; Liu, Weiwei [Key Laboratory of Lithium Battery Materials of Jiangsu Province, Institute of chemical power sources, Soochow University, Suzhou 215006 (China); Changzhou Institute of Energy Storage Materials and Devices, Changzhou 213000 (China); Xia, Bingbo; Sun, Hongdan; Zheng, Junwei [Key Laboratory of Lithium Battery Materials of Jiangsu Province, Institute of chemical power sources, Soochow University, Suzhou 215006 (China); Li, Decheng, E-mail: lidecheng@suda.edu.cn [Key Laboratory of Lithium Battery Materials of Jiangsu Province, Institute of chemical power sources, Soochow University, Suzhou 215006 (China)

2014-02-15

In this study, we synthesized a carbon coated Mn–Sn metal oxide composite with core-shell structure (MTO@C) via a simple glucose hydrothermal reaction and subsequent carbonization approach. When the MTO@C composite was applied as an anode material for lithium-ion batteries, it maintained a reversible capacity of 409 mA h g{sup −1} after 200 cycles at a current density of 100 mA g{sup −1}. The uniformed and continuous carbon layer formed on the MTO nanoparticles, effectively buffered the volumetric change of the active material and increased electronic conductivity, which thus prolonged the cycling performance of the MTO@C electrode.

Preparation and electrochemical properties of core-shell carbon coated Mn–Sn complex metal oxide as anode materials for lithium-ion batteries

International Nuclear Information System (INIS)

Zhang, Ruixue; Fang, Guoqing; Liu, Weiwei; Xia, Bingbo; Sun, Hongdan; Zheng, Junwei; Li, Decheng

2014-01-01

In this study, we synthesized a carbon coated Mn–Sn metal oxide composite with core-shell structure (MTO@C) via a simple glucose hydrothermal reaction and subsequent carbonization approach. When the MTO@C composite was applied as an anode material for lithium-ion batteries, it maintained a reversible capacity of 409 mA h g −1 after 200 cycles at a current density of 100 mA g −1 . The uniformed and continuous carbon layer formed on the MTO nanoparticles, effectively buffered the volumetric change of the active material and increased electronic conductivity, which thus prolonged the cycling performance of the MTO@C electrode.

Preparation and electrochemical properties of core-shell carbon coated Mn-Sn complex metal oxide as anode materials for lithium-ion batteries

Science.gov (United States)

Zhang, Ruixue; Fang, Guoqing; Liu, Weiwei; Xia, Bingbo; Sun, Hongdan; Zheng, Junwei; Li, Decheng

2014-02-01

In this study, we synthesized a carbon coated Mn-Sn metal oxide composite with core-shell structure (MTO@C) via a simple glucose hydrothermal reaction and subsequent carbonization approach. When the MTO@C composite was applied as an anode material for lithium-ion batteries, it maintained a reversible capacity of 409 mA h g-1 after 200 cycles at a current density of 100 mA g-1. The uniformed and continuous carbon layer formed on the MTO nanoparticles, effectively buffered the volumetric change of the active material and increased electronic conductivity, which thus prolonged the cycling performance of the MTO@C electrode.

Metal cycling within mountain pine beetle impacted watersheds of Keystone Gulch, Colorado

Science.gov (United States)

Heil, E. M.; Navarre-Sitchler, A.; Wanty, R. B.

2016-12-01

Metal cycling in mountain watersheds may be altered due to rapid landscape changes. Previous studies have examined the impact of deforestation and wildfires, on the fate and transport of metals in watersheds. However, we have only begun to understand changes in metal cycling in watersheds impacted by the mountain pine beetle. Warming climates and extended droughts have enabled pine beetles to impact larger areas. In these areas tree death occurs an average of three years after the initial infestation. In this short period of time the trees stop transpiring, defoliate, and die. The rapid deposition of pine needles to the forest floor, and subsequent decomposition of the needles, increases organic carbon (OC) availability and release metals that are stored in the impacted watersheds. Consequently, both OC and metal fluxes into and through the beetle-infested watersheds may be larger than those in non-infested watersheds. Four watersheds along Keystone Gulch Rd., located in Keystone, CO, were chosen for soil, water, and needle sampling because of their similar bedrock, drainage area, tree density and type, aspect, and their varying degree of pine beetle infestation. Sequential extractions using simulated rainwater, MgCl2, and pyrophosphate (representing soil pore water, exchangeable fraction, and organically bound metals) were performed on the Keystone Gulch soil samples to develop a better understanding of the distribution of metals in soils. Samples were classified by degree of beetle impact within and between the watersheds. The most obvious differences in the soil extractions between the four watersheds were observed for aluminum and iron and to a slightly lesser extent copper and zinc. In general, aluminum, iron, and zinc concentrations were higher while copper concentrations were lower in soils from less beetle-impacted watersheds. Metal concentrations in stream waters will be evaluated in the context of metal mobility through and out of the watershed.

Comparative alternative materials assessment to screen toxicity hazards in the life cycle of CIGS thin film photovoltaics

Energy Technology Data Exchange (ETDEWEB)

Eisenberg, Daniel A.; Yu, Mengjing; Lam, Carl W. [University of California, Davis, 1 Shields Avenue, Davis, CA 95616 (United States); Ogunseitan, Oladele A. [University of California, Irvine, Irvine, CA 92697 (United States); Schoenung, Julie M., E-mail: jmschoenung@ucdavis.edu [University of California, Davis, 1 Shields Avenue, Davis, CA 95616 (United States)

2013-09-15

Highlights: • Comparative alternatives assessment of thin film manufacturing technologies. • Development of chemical alternatives assessment in a life cycle context. • Screening of manufacturing and solar cell hazardous substances simultaneously. -- Abstract: Copper–indium–gallium–selenium–sulfide (CIGS) thin film photovoltaics are increasingly penetrating the market supply for consumer solar panels. Although CIGS is attractive for producing less greenhouse gas emissions than fossil-fuel based energy sources, CIGS manufacturing processes and solar cell devices use hazardous materials that should be carefully considered in evaluating and comparing net environmental benefits of energy products. Through this research, we present a case study on the toxicity hazards associated with alternative materials selection for CIGS manufacturing. We applied two numeric models, The Green Screen for Safer Chemicals™ and the Toxic Potential Indicator. To improve the sensitivity of the model outputs, we developed a novel, life cycle thinking based hazard assessment method that facilitates the projection of hazards throughout material life cycles. Our results show that the least hazardous CIGS solar cell device and manufacturing protocol consist of a titanium substrate, molybdenum metal back electrode, CuInS{sub 2} p-type absorber deposited by spray pyrolysis, ZnS buffer deposited by spray ion layer gas reduction, ZnO:Ga transparent conducting oxide (TCO) deposited by sputtering, and the encapsulant polydimethylsiloxane.

Feasibility Study on 3-D Printing of Metallic Structural Materials with Robotized Laser-Based Metal Additive Manufacturing

Science.gov (United States)

Ding, Yaoyu; Kovacevic, Radovan

2016-07-01

Metallic structural materials continue to open new avenues in achieving exotic mechanical properties that are naturally unavailable. They hold great potential in developing novel products in diverse industries such as the automotive, aerospace, biomedical, oil and gas, and defense. Currently, the use of metallic structural materials in industry is still limited because of difficulties in their manufacturing. This article studied the feasibility of printing metallic structural materials with robotized laser-based metal additive manufacturing (RLMAM). In this study, two metallic structural materials characterized by an enlarged positive Poisson's ratio and a negative Poisson's ratio were designed and simulated, respectively. An RLMAM system developed at the Research Center for Advanced Manufacturing of Southern Methodist University was used to print them. The results of the tensile tests indicated that the printed samples successfully achieved the corresponding mechanical properties.

Synthesis of low cycle fatigue test results

International Nuclear Information System (INIS)

Andrews, R.M.

1990-01-01

Axial strain controlled cycle fatigue tests were carried out on type 316 stainless steel parent metal, vacuum and non-vacuum electron beams welds, submerged arc welds and gas shielded metal arc welds. Testing covered total strains in the range 0.6% to 2%, and was at room temperature and 550 0 C. Parent metal and the electron beam welds showed rapid cyclic hardening, while arc welds showed little hardening. The weld metal cyclic stress-strain response was above that obtained for the parent metal, although below data obtained by other workers for similar parent materials. Weld metal endurances were above the ASME N47 continuous cycling design line at both temperatures, and comparable with parent metal data. However, the weld metal data approached the design line at low strain ranges (around 0.5%). Endurances were predicted from crack growth rates estimated from striation spacings, giving acceptable results except for the gas shielded metal arc weldments. (author)

Influence of metal dental materials on MR imaging

Energy Technology Data Exchange (ETDEWEB)

Tsuchihashi, Toshio; Chiba, Michiko; Yoshizawa, Satoshi; Sasaki, Sadayuki; Maki, Toshio; Kitagawa, Matsuo; Suzuki, Takeshi [Nippon Medical School, Tokyo (Japan). Main Hospital; Nakata, Minoru; Fujita, Isao

1998-11-01

Differences in magnetic susceptibility produce artifacts and signal loss in magnetic resonance imaging (MRI). This study was undertaken to compare the degree of artifacts on MRI caused by metallic dental materials. The influence on MRI of six types of dental alloys, a dental implant, orthodontic appliance, and magnetic attachment was investigated. Among the dental metals, nickel-chromium alloy and cobalt-chromium alloy, which have ferromagnetism, caused significant metal artifacts. Gold-platinum alloy, gold-silver-palladium alloy, silver alloy, and amalgam alloy produced slight metal artifacts. The orthodontic appliance mainly consisted of iron, and the keeper for its magnetic attachment was made of stainless steel. For these reasons, marked metal artifacts and signal loss could be seen in both of them owing to their ferromagnetism. These results suggest that orthodontic appliances and magnetic attachments impair evaluation of the GRE and EPI techniques. It is therefore preferable to use predominantly diamagnetic or paramagnetic dental materials for MRI of the head and neck. Removable keepers should be used more widely to prevent metal artifacts and enhance safety on MRI. (author)

Influence of metal dental materials on MR imaging

International Nuclear Information System (INIS)

Tsuchihashi, Toshio; Chiba, Michiko; Yoshizawa, Satoshi; Sasaki, Sadayuki; Maki, Toshio; Kitagawa, Matsuo; Suzuki, Takeshi; Nakata, Minoru; Fujita, Isao

1998-01-01

Differences in magnetic susceptibility produce artifacts and signal loss in magnetic resonance imaging (MRI). This study was undertaken to compare the degree of artifacts on MRI caused by metallic dental materials. The influence on MRI of six types of dental alloys, a dental implant, orthodontic appliance, and magnetic attachment was investigated. Among the dental metals, nickel-chromium alloy and cobalt-chromium alloy, which have ferromagnetism, caused significant metal artifacts. Gold-platinum alloy, gold-silver-palladium alloy, silver alloy, and amalgam alloy produced slight metal artifacts. The orthodontic appliance mainly consisted of iron, and the keeper for its magnetic attachment was made of stainless steel. For these reasons, marked metal artifacts and signal loss could be seen in both of them owing to their ferromagnetism. These results suggest that orthodontic appliances and magnetic attachments impair evaluation of the GRE and EPI techniques. It is therefore preferable to use predominantly diamagnetic or paramagnetic dental materials for MRI of the head and neck. Removable keepers should be used more widely to prevent metal artifacts and enhance safety on MRI. (author)

Radioactive materials transportation life-cycle cost

International Nuclear Information System (INIS)

Gregory, P.C.; Donovan, K.S.; Spooner, O.R.

1993-01-01

This paper discusses factors that should be considered when estimating the life-cycle cost of shipping radioactive materials and the development of a working model that has been successfully used. Today's environmental concerns have produced an increased emphasis on cleanup and restoration of production plants and interim storage sites for radioactive materials. The need to transport these radioactive materials to processing facilities or permanent repositories is offset by the reality of limited resources and ever-tightening budgets. Obtaining the true cost of transportation is often difficult because of the many direct and indirect costs involved and the variety of methods used to account for fixed and variable expenses. In order to make valid comparisons between the cost of alternate transportation systems for new and/or existing programs, one should consider more than just the cost of capital equipment or freight cost per mile. Of special interest is the cost of design, fabrication, use, and maintenance of shipping containers in accordance with the requirements of the U.S. Nuclear Regulatory Commission. A spread sheet model was developed to compare the life-cycle costs of alternate fleet configurations of TRUPACT-II, which will be used to ship transuranic waste from U.S. Department of Energy sites to the Waste Isolation Pilot Plant near Carlsbad, New Mexico

Chemical compatibility of structural materials in alkali metals

International Nuclear Information System (INIS)

Natesan, K.; Rink, D.L.; Haglund, R.

1995-01-01

The objectives of this task are to (a) evaluate the chemical compatibility of structural alloys such as V-5 wt.%Cr-5 wt.%Ti alloy and Type 316 stainless steel for application in liquid alkali metals such as lithium and sodium-78 wt.% potassium (NaK) at temperatures in the range that are of interest for International Thermonuclear Experimental Reactor (ITER); (b) evaluate the transfer of nonmetallic elements such as oxygen, nitrogen, carbon, and hydrogen between structural materials and liquid metals; and (c) evaluate the effects of such transfers on the mechanical and microstructural characteristics of the materials for long-term service in liquid-metal-environments

The neutronic and fuel cycle performance of interchangeable 3500 MWth metal and oxide fueled LMRs

International Nuclear Information System (INIS)

Fujita, E.K.; Wade, D.C.

1990-01-01

This study summarizes the neutronic and fuel cycle analysis performed at Argonne National Laboratory for an oxide and a metal fueled 3500 MWth LMR. These reactor designs formed the basis for a joint US/European study of LMR ATWS events. The oxide and metal core designs were developed to meet reactor performance specifications that are constrained by requirements for core loading interchangeability and for a small burnup reactivity swing. Differences in the computed performance parameters of the oxide and metal cores, arising from basic differences in their neutronic characteristics, are identified and discussed. It is shown that metal and oxide cores designed to the same ground rules exhibit many similar performance characteristics; however, they differ substantially in reactivity coefficients, control strategies, and fuel cycle options. 12 refs., 2 figs., 12 tabs

Influence of hole transport material/metal contact interface on perovskite solar cells

Science.gov (United States)

Lei, Lei; Zhang, Shude; Yang, Songwang; Li, Xiaomin; Yu, Yu; Wei, Qingzhu; Ni, Zhichun; Li, Ming

2018-06-01

Interfaces have a significant impact on the performance of perovskite solar cells. This work investigated the influence of hole transport material/metal contact interface on photovoltaic behaviours of perovskite solar devices. Different hole material/metal contact interfaces were obtained by depositing the metal under different conditions. High incident kinetic energy metal particles were proved to penetrate and embed into the hole transport material. These isolated metal particles in hole transport materials capture holes and increase the apparent carrier transport resistance of the hole transport layer. Sample temperature was found to be of great significance in metal deposition. Since metal vapour has a high temperature, the deposition process accumulated a large amount of heat. The heat evaporated the additives in the hole transport layer and decreased the hole conductivity. On the other hand, high temperature may cause iodization of the metal contact.

High-Performance Corrosion-Resistant Materials: Iron-Based Amorphous-Metal Thermal-Spray Coatings

International Nuclear Information System (INIS)

Farmer, J C; Haslam, J J; Wong, F; Ji, X; Day, S D; Branagan, D J; Marshall, M C; Meacham, B E; Buffa, E J; Blue, C A; Rivard, J K; Beardsley, M B; Weaver, D T; Aprigliano, L F; Kohler, L; Bayles, R; Lemieux, E J; Wolejsza, T M; Martin, F J; Yang, N; Lucadamo, G; Perepezko, J H; Hildal, K; Kaufman, L; Heuer, A H; Ernst, F; Michal, G M; Kahn, H; Lavernia, E J

2004-01-01

The multi-institutional High Performance Corrosion Resistant Materials (HPCRM) Team is cosponsored by the Defense Advanced Projects Agency (DARPA) Defense Science Office (DSO) and the Department of Energy (DOE) Office of Civilian Radioactive Waste Management (OCRWM), and has developed new corrosion-resistant, iron-based amorphous metals that can be applied as coatings with advanced thermal spray technology. Two compositions have corrosion resistance superior to wrought nickel-based Alloy C-22 (UNS No. N06022) in very aggressive environments, including concentrated calcium-chloride brines at elevated temperature. Corrosion costs the Department of Defense billions of dollars every year, with an immense quantity of material in various structures undergoing corrosion. For example, in addition to fluid and seawater piping, ballast tanks, and propulsions systems, approximately 345 million square feet of structure aboard naval ships and crafts require costly corrosion control measures. The use of advanced corrosion-resistant materials to prevent the continuous degradation of this massive surface area would be extremely beneficial. The Fe-based corrosion-resistant, amorphous-metal coatings under development may prove of importance for applications on ships. Such coatings could be used as an ''integral drip shield'' on spent fuel containers, as well as protective coatings that could be applied over welds, thereby preventing exposure to environments that might cause stress corrosion cracking. In the future, such new high-performance iron-based materials could be substituted for more-expensive nickel-based alloys, thereby enabling a reduction in the $58-billion life cycle cost for the long-term storage of the Nation's spent nuclear fuel by tens of percent

Metal-doped sodium aluminium hydrides as potential new hydrogen storage materials

Energy Technology Data Exchange (ETDEWEB)

Bogdanovic, B. [Max-Planck-Institut fuer Kohlenforschung, Muelheim an der Ruhr (Germany); Brand, R.A. [Department of Physics, Gerhard-Mercator-Universitaet GH Duisburg, D-47048, Duisburg (Germany); Marjanovic, A.; Schwickardi, M.; Toelle, J. [Max-Planck-Institut fuer Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470, Muelheim an der Ruhr (Germany)

2000-04-28

Thermodynamics and kinetics of the reversible dissociation of metal-doped NaAlH{sub 4} as a hydrogen (or heat) storage system have been investigated in some detail. The experimentally determined enthalpies for the first (3.7 wt% of H) and the second dissociation step of Ti-doped NaAlH{sub 4} (3.0 wt% H) of 37 and 47 kJ/mol are in accordance with low and medium temperature reversible metal hydride systems, respectively. Through variation of NaAlH{sub 4} particle sizes, catalysts (dopants) and doping procedures, kinetics as well as the cyclization stability within cycle tests have been substantially improved with respect to the previous status [B. Bogdanovic, M. Schwickardi (1997)]. In particular, using combinations of Ti and Fe compounds as dopants, a cooperative (synergistic) catalytic effect of the metals Ti and Fe in enhancing rates of both de- and rehydrogenation of Ti/Fe-doped NaAlH{sub 4} within cycle tests, reaching a constant storage capacity of {proportional_to}4 wt% H{sub 2}, has been demonstrated. By means of {sup 57}Fe Moessbauer spectroscopy of the Ti/Fe-doped NaAlH{sub 4} before and throughout a cycle test, it has been ascertained that (1) during the doping procedure, nanosize metallic Fe particles are formed from the doping agent Fe(OEt){sub 2} and (2) already after the first dehydrogenation, the nanosize Fe particles with NaAlH{sub 4} present are probably transformed into an Fe-Al-alloy which throughout the cycle test remains practically unchanged. (orig.)

Model of bidirectional reflectance distribution function for metallic materials

International Nuclear Information System (INIS)

Wang Kai; Zhu Jing-Ping; Liu Hong; Hou Xun

2016-01-01

Based on the three-component assumption that the reflection is divided into specular reflection, directional diffuse reflection, and ideal diffuse reflection, a bidirectional reflectance distribution function (BRDF) model of metallic materials is presented. Compared with the two-component assumption that the reflection is composed of specular reflection and diffuse reflection, the three-component assumption divides the diffuse reflection into directional diffuse and ideal diffuse reflection. This model effectively resolves the problem that constant diffuse reflection leads to considerable error for metallic materials. Simulation and measurement results validate that this three-component BRDF model can improve the modeling accuracy significantly and describe the reflection properties in the hemisphere space precisely for the metallic materials. (paper)

Model of bidirectional reflectance distribution function for metallic materials

Science.gov (United States)

Wang, Kai; Zhu, Jing-Ping; Liu, Hong; Hou, Xun

2016-09-01

Based on the three-component assumption that the reflection is divided into specular reflection, directional diffuse reflection, and ideal diffuse reflection, a bidirectional reflectance distribution function (BRDF) model of metallic materials is presented. Compared with the two-component assumption that the reflection is composed of specular reflection and diffuse reflection, the three-component assumption divides the diffuse reflection into directional diffuse and ideal diffuse reflection. This model effectively resolves the problem that constant diffuse reflection leads to considerable error for metallic materials. Simulation and measurement results validate that this three-component BRDF model can improve the modeling accuracy significantly and describe the reflection properties in the hemisphere space precisely for the metallic materials.

Comparative alternative materials assessment to screen toxicity hazards in the life cycle of CIGS thin film photovoltaics.

Science.gov (United States)

Eisenberg, Daniel A; Yu, Mengjing; Lam, Carl W; Ogunseitan, Oladele A; Schoenung, Julie M

2013-09-15

Copper-indium-gallium-selenium-sulfide (CIGS) thin film photovoltaics are increasingly penetrating the market supply for consumer solar panels. Although CIGS is attractive for producing less greenhouse gas emissions than fossil-fuel based energy sources, CIGS manufacturing processes and solar cell devices use hazardous materials that should be carefully considered in evaluating and comparing net environmental benefits of energy products. Through this research, we present a case study on the toxicity hazards associated with alternative materials selection for CIGS manufacturing. We applied two numeric models, The Green Screen for Safer Chemicals and the Toxic Potential Indicator. To improve the sensitivity of the model outputs, we developed a novel, life cycle thinking based hazard assessment method that facilitates the projection of hazards throughout material life cycles. Our results show that the least hazardous CIGS solar cell device and manufacturing protocol consist of a titanium substrate, molybdenum metal back electrode, CuInS₂ p-type absorber deposited by spray pyrolysis, ZnS buffer deposited by spray ion layer gas reduction, ZnO:Ga transparent conducting oxide (TCO) deposited by sputtering, and the encapsulant polydimethylsiloxane. Copyright © 2013 Elsevier B.V. All rights reserved.

Corrosion of Structural Materials for Advanced Supercritical Carbon- Dioxide Brayton Cycle

Energy Technology Data Exchange (ETDEWEB)

Sridharan, Kumar [Univ. of Wisconsin, Madison, WI (United States)

2017-05-13

The supercritical carbon-dioxide (referred to as SC-CO₂ hereon) Brayton cycle is being considered for power conversion systems for a number of nuclear reactor concepts, including the sodium fast reactor (SFR), fluoride saltcooled high temperature reactor (FHR), and high temperature gas reactor (HTGR), and several types of small modular reactors (SMR). The SC-CO₂ direct cycle gas fast reactor has also been recently proposed. The SC-CO₂ Brayton cycle (discussed in Chapter 1) provides higher efficiencies compared to the Rankine steam cycle due to less compression work stemming from higher SC-CO₂ densities, and allows for smaller components size, fewer components, and simpler cycle layout. For example, in the case of a SFR using a SC-CO₂ Brayton cycle instead of a steam cycle would also eliminate the possibility of sodium-water interactions. The SC-CO₂ cycle has a higher efficiency than the helium Brayton cycle, with the additional advantage of being able to operate at lower temperatures and higher pressures. In general, the SC-CO₂ Brayton cycle is well-suited for any type of nuclear reactor (including SMR) with core outlet temperature above ~ 500°C in either direct or indirect versions. In all the above applications, materials corrosion in high temperature SC-CO₂ is an important consideration, given their expected lifetimes of 20 years or longer. Our discussions with National Laboratories and private industry early on in this project indicated materials corrosion to be one of the significant gaps in the implementation of SC-CO₂ Brayton cycle. Corrosion can lead to a loss of effective load-bearing wall thickness of a component and can potentially lead to the generation of oxide particulate debris which can lead to three-body wear in turbomachinery components. Another environmental degradation effect that is rather unique to CO₂ environment is the possibility

Failure of metals III: Fracture and fatigue of nanostructured metallic materials

International Nuclear Information System (INIS)

Pineau, André; Amine Benzerga, A.; Pardoen, Thomas

2016-01-01

Pushing the internal or external dimensions of metallic alloys down to the nanometer scale gives rise to strong materials, though most often at the expense of a low ductility and a low resistance to cracking, with negative impact on the transfer to engineering applications. These characteristics are observed, with some exceptions, in bulk ultra-fine grained and nanocrystalline metals, nano-twinned metals, thin metallic coatings on substrates and freestanding thin metallic films and nanowires. This overview encompasses all these systems to reveal commonalities in the origins of the lack of ductility and fracture resistance, in factors governing fatigue resistance, and in ways to improve properties. After surveying the various processing methods and key deformation mechanisms, we systematically address the current state of the art in terms of plastic localization, damage, static and fatigue cracking, for three classes of systems: (1) bulk ultra-fine grained and nanocrystalline metals, (2) thin metallic films on substrates, and (3) 1D and 2D freestanding micro and nanoscale systems. In doing so, we aim to favour cross-fertilization between progress made in the fields of mechanics of thin films, nanomechanics, fundamental researches in bulk nanocrystalline metals and metallurgy to impart enhanced resistance to fracture and fatigue in high-strength nanostructured systems. This involves exploiting intrinsic mechanisms, e.g. to enhance hardening and rate-sensitivity so as to delay necking, or improve grain-boundary cohesion to resist intergranular cracks or voids. Extrinsic methods can also be utilized such as by hybridizing the metal with another material to delocalize the deformation - as practiced in stretchable electronics. Fatigue crack initiation is in principle improved by a fine structure, but at the expense of larger fatigue crack growth rates. Extrinsic toughening through hybridization allows arresting or bridging cracks. The content and discussions are based on

Experimental modeling of weld thermal cycle of the heat affected zone (HAZ

Directory of Open Access Journals (Sweden)

J. Kulhánek

2016-10-01

Full Text Available Contribution deals with experimental modeling of quick thermal cycles of metal specimens. In the introduction of contribution will be presented measured graphs of thermal cycle of heat affected zone (HAZ of weld. Next will be presented experimental simulation of measured thermal cycle on the standard specimens, useable for material testing. This approach makes possible to create material structures of heat affected zone of weld, big enough for standard material testing.

Liquid metal reactor core material HT9

International Nuclear Information System (INIS)

Kim, S. H.; Kuk, I. H.; Ryu, W. S. and others

1998-03-01

A state-of-the art is surveyed on the liquid metal reactor core materials HT9. The purpose of this report is to give an insight for choosing and developing the materials to be applied to the KAERI prototype liquid metal reactor which is planned for the year of 2010. In-core stability of cladding materials is important to the extension of fuel burnup. Austenitic stainless steel (AISI 316) has been used as core material in the early LMR due to the good mechanical properties at high temperatures, but it has been found to show a poor swelling resistance. So many efforts have been made to solve this problem that HT9 have been developed. HT9 is 12Cr-1MoVW steel. The microstructure of HT9 consisted of tempered martensite with dispersed carbide. HT9 has superior irradiation swelling resistance as other BCC metals, and good sodium compatibility. HT9 has also a good irradiation creep properties below 500 dg C, but irradiation creep properties are degraded above 500 dg C. Researches are currently in progress to modify the HT9 in order to improve the irradiation creep properties above 500 dg C. New design studies for decreasing the core temperature below 500 dg C are needed to use HT9 as a core material. On the contrary, decrease of the thermal efficiency may occur due to lower-down of the operation temperature. (author). 51 refs., 6 tabs., 19 figs

Solar Cycle Response and Long-Term Trends in the Mesospheric Metal Layers

Science.gov (United States)

Dawkins, E. C. M.; Plane, J. M. C.; Chipperfield, M.; Feng, W.; Marsh, D. R.; Hoffner, J.; Janches, D.

2016-01-01

The meteoric metal layers (Na, Fe, and K) which form as a result of the ablation of incoming meteors act as unique tracers for chemical and dynamical processes that occur within the upper mesosphere lower thermosphere region. In this work, we examine whether these metal layers are sensitive Fe indicators of decadal long-term changes within the upper atmosphere. Output from a whole-atmosphere climate model is used to assess the response of the Na, K, and Fe layers across a 50 year period (1955-2005). At short timescales, the K layer has previously been shown to exhibit a very different seasonal behavior compared to the other metals. Here we show that this unusual behavior is also exhibited at longer time scales (both the 11 year solar cycle and 50 year periods), where K displays a much more pronounced response to atmospheric temperature changes than either Na or Fe. The contrasting solar cycle behavior of the K and Na layers predicted by the model is confirmed using satellite and lidar observations for the period 2004-2013.

Surface properties of ceramic/metal composite materials for thermionic converter applications

International Nuclear Information System (INIS)

Davis, P.R.; Bozack, M.J.; Swanson, L.W.

1983-01-01

Ceramic/metal composite electrode materials are of interest for thermionic energy conversion (TEC) applications for several reasons. These materials consist of submicron metal fibers or islands in an oxide matrix and therefore provide a basis for fabricating finely structured electrodes, with projecting or recessed metallic regions for more efficient electron emission or collection. Furthermore, evaporation and surface diffusion of matrix oxides may provide oxygen enhancement of cesium adsorption and work function lowering at both the collecting and emitting electrode surfaces of the TEC. Finally, the high work function oxide matrix or oxide-metal interfaces may provide efficient surface ionization of cesium for space-charge reduction in the device. The authors are investigating two types of ceramic/metal composite materials. One type is a directionally solidified eutectic consisting of a bulk oxide matrix such as UO 2 or stabilized ZrO 2 with parallel metal fibers (W) running through the oxide being exposed at the surface by cutting perpendicular to the fiber direction. The second type of material, called a surface eutectic, consists of a refractory substrate (Mo) with a thin layer of deposited and segregated material (Mo-Cr 2 O 3 -A1 2 O 3 ) on the surface. The final configuration of this layer is an oxide matrix with metallic islands scattered throughout

Microporous Metal Organic Materials for Hydrogen Storage

Energy Technology Data Exchange (ETDEWEB)

S. G. Sankar; Jing Li; Karl Johnson

2008-11-30

We have examined a number of Metal Organic Framework Materials for their potential in hydrogen storage applications. Results obtained in this study may, in general, be summarized as follows: (1) We have identified a new family of porous metal organic framework materials with the compositions M (bdc) (ted){sub 0.5}, {l_brace}M = Zn or Co, bdc = biphenyl dicarboxylate and ted = triethylene diamine{r_brace} that adsorb large quantities of hydrogen ({approx}4.6 wt%) at 77 K and a hydrogen pressure of 50 atm. The modeling performed on these materials agree reasonably well with the experimental results. (2) In some instances, such as in Y{sub 2}(sdba){sub 3}, even though the modeling predicted the possibility of hydrogen adsorption (although only small quantities, {approx}1.2 wt%, 77 K, 50 atm. hydrogen), our experiments indicate that the sample does not adsorb any hydrogen. This may be related to the fact that the pores are extremely small or may be attributed to the lack of proper activation process. (3) Some samples such as Zn (tbip) (tbip = 5-tert butyl isophthalate) exhibit hysteresis characteristics in hydrogen sorption between adsorption and desorption runs. Modeling studies on this sample show good agreement with the desorption behavior. It is necessary to conduct additional studies to fully understand this behavior. (4) Molecular simulations have demonstrated the need to enhance the solid-fluid potential of interaction in order to achieve much higher adsorption amounts at room temperature. We speculate that this may be accomplished through incorporation of light transition metals, such as titanium and scandium, into the metal organic framework materials.

Laser assisted embedding of nanoparticles into metallic materials

International Nuclear Information System (INIS)

Lin Dong; Suslov, Sergey; Ye Chang; Liao Yiliang; Liu, C. Richard; Cheng, Gary J.

2012-01-01

This paper reports a methodology of half-embedding nanoparticles into metallic materials. Transparent and opaque nanoparticles are chosen to demonstrate the process of laser assisted nanoparticle embedding. Dip coating method is used to coat transparent or opaque nanoparticle on the surface of metallic material. Nanoparticles are embedded into substrate by laser irradiation. In this study, the mechanism and process of nanoparticle embedding are investigated. It is found both transparent and opaque nanoparticles embedding are with high densities and good uniformities.

Hierarchical structured graphene/metal oxide/porous carbon composites as anode materials for lithium-ion batteries

Energy Technology Data Exchange (ETDEWEB)

Guo, Rong [Beijing Key Laboratory of Energy Conversion and Storage Materials, College of Chemistry, Beijing Normal University, Beijing 100875 (China); Yue, Wenbo, E-mail: wbyue@bnu.edu.cn [Beijing Key Laboratory of Energy Conversion and Storage Materials, College of Chemistry, Beijing Normal University, Beijing 100875 (China); Ren, Yu [National Institute of Clean-and-Low-Carbon Energy, Beijing 102209 (China); Zhou, Wuzong [School of Chemistry, University of St. Andrews, St. Andrews, Fite KY16 9ST (United Kingdom)

2016-01-15

Highlights: • CeO{sub 2} and Co{sub 3}O{sub 4} nanoparticles display different behavior within CMK-3. • CMK-3-CeO{sub 2} and Co{sub 3}O{sub 4} show various electrochemical properties • CMK-3-CeO{sub 2} and Co{sub 3}O{sub 4} are further wrapped by graphene nanosheets. • Graphene-encapsulated composites show better electrochemical performances. - Abstract: As a novel anode material for lithium-ion batteries, CeO{sub 2} displays imperceptible volumetric and morphological changes during the lithium insertion and extraction processes, and thereby exhibits good cycling stability. However, the low theoretical capacity and poor electronic conductivity of CeO{sub 2} hinder its practical application. In contrast, Co{sub 3}O{sub 4} possesses high theoretical capacity, but undergoes huge volume change during cycling. To overcome these issues, CeO{sub 2} and Co{sub 3}O{sub 4} nanoparticles are formed inside the pores of CMK-3 and display various electrochemical behaviors due to the different morphological structures of CeO{sub 2} and Co{sub 3}O{sub 4} within CMK-3. Moreover, the graphene/metal oxide/CMK-3 composites with a hierarchical structure are then prepared and exhibit better electrochemical performances than metal oxides with or without CMK-3. This novel synthesis strategy is hopefully employed in the electrode materials design for Li-ion batteries or other energy conversion and storage devices.

Organic derivatives of lanthanides containing metal in cycle

International Nuclear Information System (INIS)

Syutkina, O.P.; Rybakova, L.F.; Egorova, E.N.; Sigalov, A.B.; Beletskaya, I.P.

1983-01-01

The reaction of 2.2'-dilithium biphenyl with LnBr 3 (Ln=Pr, Sm, Gd, Ho, Yb here bromium atoms are comparatively easily replaced. Previously unknown organic derivatives of lanthanides containing metal in the cycle are obtained. It is established that a successful extraction of the compound requires reaction conditions, such as the use of ether as a solvent with the followinq addition of TGP, the order of addition of reagents. Compounds are extracted in the form of solvates containing TGP melecules. The complexes prepared are coloured, depending on the metal, beige (Pr, Sm) brown (Gd, Yb) and red-brown (Ho). They dissolve readily in TGP moderately in benzen toluene, CCl 4 . When stored their solubility in benzene and CCl 4 decreases considerably, and after 3-2 days, they are practically insoluhle. The compounds prepared are characterized by the elementary analysis, IR and PMR spectra

Metal-ceramic materials. Study and prediction of effective mechanical properties

International Nuclear Information System (INIS)

Karakulov, Valerii V.; Smolin, Igor Yu.

2016-01-01

Mechanical behavior of stochastic metal-ceramic composite materials was numerically simulated on mesoscopic scale level. Deformation of mesoscopic volumes of composites, whose structure consists of a metal matrix and randomly distributed ceramic inclusions, was numerically simulated. The results of the numerical simulation were used for evaluation of the effective elastic and strength properties of metal-ceramic materials with different parameters of the structure. The values of the effective mechanical properties of investigated materials were obtained, and the character of the dependence of the effective elastic and strength properties on the structure parameters of composites was determined.

Facile and large-scale preparation of sandwich-structured graphene-metal oxide composites as anode materials for Li-ion batteries

International Nuclear Information System (INIS)

Fang, Hongmei; Zhao, Li; Yue, Wenbo; Wang, Yuan; Jiang, Yang; Zhang, Yuan

2015-01-01

Graphene-based metal oxides are desirable as potential anode materials for lithium-ion batteries (LIBs) owing to their superior electrochemical properties. In this work, sandwich-structured graphene-metal oxide (ZnO, NiO) composites are facilely synthesized on a large scale through self-assembly of graphene oxide nanosheets and metal ammine complexes, and then thermal decomposition of the self-assembled products. ZnO or NiO nanoparticles with diameters of 5∼10 nm are immobilized between the layers of graphene nanosheets, which may provide the space for accommodating the volume change of metal oxides during cycles, and highly improve the electronic conductivity of the composites. Accordingly, these sandwich-structured composites exhibit enhanced electrochemical performances compared to metal oxide particles or stacked graphene nanosheets. This facile synthesis method is very suitable for the large-scale production of three-dimensional graphene-based composites as high-performance anodes for LIBs.

Filter materials for metal removal from mine drainage--a review.

Science.gov (United States)

Westholm, Lena Johansson; Repo, Eveliina; Sillanpää, Mika

2014-01-01

A large number of filter materials, organic and inorganic, for removal of heavy metals in mine drainage have been reviewed. Bark, chitin, chitosan, commercial ion exchangers, dairy manure compost, lignite, peat, rice husks, vegetal compost, and yeast are examples of organic materials, while bio-carbons, calcareous shale, dolomite, fly ash, limestone, olivine, steel slag materials and zeolites are examples of inorganic materials. The majority of these filter materials have been investigated in laboratory studies, based on various experimental set-ups (batch and/or column tests) and different conditions. A few materials, for instance steel slag materials, have also been subjects to field investigations under real-life conditions. The results from these investigations show that steel slag materials have the potential to remove heavy metals under different conditions. Ion exchange has been suggested as the major metal removal mechanisms not only for steel slag but also for lignite. Other suggested removal mechanisms have also been identified. Adsorption has been suggested important for activated carbon, precipitation for chitosan and sulphate reduction for olivine. General findings indicate that the results with regard to metal removal vary due to experimental set ups, composition of mine drainage and properties of filter materials and the discrepancies between studies renders normalisation of data difficult. However, the literature reveals that Fe, Zn, Pb, Hg and Al are removed to a large extent. Further investigations, especially under real-life conditions, are however necessary in order to find suitable filter materials for treatment of mine drainage.

Development, characterization and evaluation of materials for open cycle MHD. Quarterly report for the period ending June 1978

Energy Technology Data Exchange (ETDEWEB)

Bates, J.L.; Marchant, D.D.; Daniel, J.L.

1978-10-01

The objectives of this program are directed toward the development and characterization of high temperature ceramics for open-cycle, coal-fired MHD power generators. The current activities are directed to electrode and insulator materials, and include (1) determination of the effects of alkali seed on the behavior of ceramics in a dc electric field; (2) development and testing of improved high temperature ceramic electrodes and insulators with controlled composition, microstructure, and properties; and (3) characterization and evaluation of materials utilized in channels being tested for MHD power generator development. Research is reported on (1) evaluation of metal electrodes from 250 hour MHD test, (2) characterization and properties of USSR MgO insulating wall material, (3) thermal diffusivity/thermal conductivity of electrode and insulator materials, (4) coprecipitation of ceramic powders, (5) properties of yttria chromites, and (6) rare earth hafnates. (WHK)

Metal modified graphite. An innovative material for systems converting electro-chemical energy; Metallmodifizierter Graphit. Ein innovativer Werkstoff fuer Systeme zur elektrochemischen Energieumwandlung

Energy Technology Data Exchange (ETDEWEB)

Mayer, Peter

2007-07-23

The work deals with metal modification of graphite electrodes in a water-acid electrolyte solution. The target is to improve the catalytic properties of graphite electrodes as they are applied in redox storage batteries for storing electric energy. Different carbon and graphite materials were used and coated electro-chemically with different metals. After being coated with metal the graphite and carbon electrodes were investigated in terms of changing their catalytic properties by means of impedance measurements. It was shown, a metal coating without a prior activation with electro-chemical oxidation-reduction cycles only results in a low or zero increase of the catalytic properties. Investigations at the electrode material glass carbon showed, a prior activation of the electrode surface by means of electro-chemical oxidation-reduction cycles decreases the penetration resistance. The activation of the glass carbon surface prior to the surface coating with metal is favourable to the electro-chemical properties of the metal-modified electrode. All carbon types, which were used in this work, could be activated at a different level by means of electro-chemical oxidation-reduction cycles depending on the carbon type. The investigations further showed that the edge levels of the carbon were activated by means of the electro-chemical oxidation-reduction cycles. The metal precipitation favourably occurs at the activated positions. (orig.) [German] Die Arbeit befasst sich mit der Metallmodifizierung von Graphitelektroden in waessriger saurer Elektrolytloesung. Ziel ist es die katalytischen Eigenschaften von Graphitelektroden wie sie in Redoxspeicherbatterien zur Speicherung von elektrischer Energie eingesetzt werden zu verbessern. Fuer die Untersuchungen wurden unterschiedliche Kohlenstoff und Graphitmaterialien eingesetzt, die elektrochemisch mit verschiedenen Metallen belegt wurden. Die Graphit- und Kohlenstoffelektroden wurden nach der Metallbelegung durch

New multifunctional lightweight materials based on cellular metals - manufacturing, properties and applications

International Nuclear Information System (INIS)

Stephani, Guenter; Quadbeck, Peter; Andersen, Olaf

2009-01-01

Cellular metallic materials are a new class of materials which have been the focus of numerous scientific studies over the past few years. The increasing interest in cellular metals is due to the fact that the introduction of pores into the materials significantly lowers the density. These highly porous materials also possess combinations of properties which are not possible to achieve with other materials. Besides the drastic weight and material savings that arise from the cell structure, there are also other application-specific benefits such as noise and energy absorption, heat insulation, mechanical damping, filtration effects and also catalytic properties. Cellular metallic materials are hence multi-functional lightweight materials.

Liquid metal mist cooling and MHD Ericsson cycle for fusion energy conversion

International Nuclear Information System (INIS)

Greenspan, E.

1989-01-01

The combination of liquid metal mist coolant and a liquid metal MHD (LMMHD) energy conversion system (ECS) based on the Ericsson cycle is being proposed for high temperature fusion reactors. It is shown that the two technologies are highly matchable, both thermodynamically and physically. Thermodynamically, the author enables delivering the fusion energy to the cycle with probably the highest practical average temperature commensurate with a given maximum reactor design constraint. Physically, the mist cooling and LMMHD ECSs can be coupled directly, thus eliminating the need for primary heat exchangers and reheaters. The net result is expected to be a high efficiency, simple and reliable heat transport and ECS. It is concluded that the proposed match could increase the economic viability of fusion reactors, so that a thorough study of the two complementary technologies is recommended. 11 refs., 3 figs

Materials reliability in the back end of the nuclear fuel cycle

International Nuclear Information System (INIS)

1987-05-01

Operating experience of nuclear fuel cycle facilities has proved that the performance and availability of key equipment largely depend on the reliability of its construction materials. In general, the materials of construction have performed well in accordance with the design criteria of equipment. In some cases, however, materials failure problems have been encountered, the causes of which are related to their corrosion and mechanical degradation. In response to the growing interest in these topics, the IAEA convened the Technical Committee Meeting on ''Materials Reliability in the Back-End of the Nuclear Fuel Cycle'' at its Headquarters from September 2 to 5, 1986. This Technical Document contains the 15 papers presented during the Meeting. Material aspects of the following fields of the back-end of the nuclear fuel cycle are covered: interim and long-term storage of spent fuel; final disposal of spent fuel; storage and vitrification of High Level Liquid Wastes (HLLW); long-term storage of High Level Wastes (HLW); and spent fuel treatment

Impacts of Vehicle Weight Reduction via Material Substitution on Life-Cycle Greenhouse Gas Emissions.

Science.gov (United States)

Kelly, Jarod C; Sullivan, John L; Burnham, Andrew; Elgowainy, Amgad

2015-10-20

This study examines the vehicle-cycle and vehicle total life-cycle impacts of substituting lightweight materials into vehicles. We determine part-based greenhouse gas (GHG) emission ratios by collecting material substitution data and evaluating that alongside known mass-based GHG ratios (using and updating Argonne National Laboratory's GREET model) associated with material pair substitutions. Several vehicle parts are lightweighted via material substitution, using substitution ratios from a U.S. Department of Energy report, to determine GHG emissions. We then examine fuel-cycle GHG reductions from lightweighting. The fuel reduction value methodology is applied using FRV estimates of 0.15-0.25, and 0.25-0.5 L/(100km·100 kg), with and without powertrain adjustments, respectively. GHG breakeven values are derived for both driving distance and material substitution ratio. While material substitution can reduce vehicle weight, it often increases vehicle-cycle GHGs. It is likely that replacing steel (the dominant vehicle material) with wrought aluminum, carbon fiber reinforced plastic (CRFP), or magnesium will increase vehicle-cycle GHGs. However, lifetime fuel economy benefits often outweigh the vehicle-cycle, resulting in a net total life-cycle GHG benefit. This is the case for steel replaced by wrought aluminum in all assumed cases, and for CFRP and magnesium except for high substitution ratio and low FRV.

Immobilization of Bacillus subtilis lipase on a Cu-BTC based hierarchically porous metal-organic framework material: a biocatalyst for esterification.

Science.gov (United States)

Cao, Yu; Wu, Zhuofu; Wang, Tao; Xiao, Yu; Huo, Qisheng; Liu, Yunling

2016-04-28

Bacillus subtilis lipase (BSL2) has been successfully immobilized into a Cu-BTC based hierarchically porous metal-organic framework material for the first time. The Cu-BTC hierarchically porous MOF material with large mesopore apertures is prepared conveniently by using a template-free strategy under mild conditions. The immobilized BSL2 presents high enzymatic activity and perfect reusability during the esterification reaction. After 10 cycles, the immobilized BSL2 still exhibits 90.7% of its initial enzymatic activity and 99.6% of its initial conversion.

Metal-Organic Framework Derived Iron Sulfide-Carbon Core-Shell Nanorods as a Conversion-Type Battery Material

DEFF Research Database (Denmark)

Huang, Wei; Li, Shuo; Cao, Xianyi

2017-01-01

of a redox conversion-type lithium-ion battery, this composite material has demonstrated high lithium-ion storage capacity at 1148 mA h g-1 under the current rate of 500 mA g-1 for 170 cycles and an impressive rate-retention capability at 657 mA h g-1 with a current density of 2000 mA g-1. On the basis......We report the design and nanoengineering of carbon-film-coated iron sulfide nanorods (C@Fe7S8) as an advanced conversion-type lithium-ion storage material. The structural advantages of the iron-based metal-organic framework (MIL-88-Fe) as both a sacrificed template and a precursor are explored...

Design of multi materials combining crystalline and amorphous metallic alloys

International Nuclear Information System (INIS)

Volland, A.; Ragani, J.; Liu, Y.; Gravier, S.; Suéry, M.; Blandin, J.J.

2012-01-01

Highlights: ► Elaboration of multi materials associating metallic glasses and conventional crystalline alloys by co-deformation performed at temperatures close to the glass transition temperature of the metallic glasses. ► Elaboration of filamentary metal matrix composites with a core in metallic glass by co extrusion. ► Sandwich structures produced by co-pressing. ► Detection of atomic diffusion from the glass to the crystalline alloys during the processes. ► Good interfaces between the metallic glasses and the crystalline alloys, as confirmed by mechanical characterisation. - Abstract: Multi materials, associating zirconium based bulk metallic glasses and crystalline metallic alloys like magnesium alloys or copper are elaborated by co-deformation processing performed in the supercooled liquid regions (SLR) of the bulk metallic glasses. Two processes are investigated: co-extrusion and co-pressing. In the first case, filamentary composites with various designs can be produced whereas in the second case sandwich structures are obtained. The experimental window (temperature, time) in which processing can be carried out is directly related to the crystallisation resistance of the glass which requires getting information about the crystallisation conditions in the selected metallic glasses. Thermoforming windows are identified for the studied BMGs by thermal analysis and compression tests in their SLR. The mechanical properties of the produced multi materials are investigated thanks to specifically developed mechanical devices and the interfaces between the amorphous and the crystalline alloys are characterised.

Comparison of properties of silver-metal oxide electrical contact materials

Directory of Open Access Journals (Sweden)

Ćosović V.

2012-01-01

Full Text Available Changes in physical properties such as density, porosity, hardness and electrical conductivity of the Ag-SnO2 and Ag-SnO2In2O3 electrical contact materials induced by introduction of metal oxide nanoparticles were investigated. Properties of the obtained silver-metal oxide nanoparticle composites are discussed and presented in comparison to their counterparts with the micro metal oxide particles as well as comparable Ag-SnO2WO3 and Ag-ZnO contact materials. Studied silvermetal oxide composites were produced by powder metallurgy method from very fine pure silver and micro- and nanoparticle metal oxide powders. Very uniform microstructures were obtained for all investigated composites and they exhibited physical properties that are comparable with relevant properties of equivalent commercial silver based electrical contact materials. Both Ag-SnO2 and Ag- SnO2In2O3 composites with metal oxide nanoparticles were found to have lower porosity, higher density and hardness than their respective counterparts which can be attributed to better dispersion hardening i.e. higher degree of dispersion of metal oxide in silver matrix.

Recent Advances as Materials of Functional Metal-Organic Frameworks

Directory of Open Access Journals (Sweden)

Xiao-Lan Tong

2013-01-01

Full Text Available Metal-organic frameworks (MOFs, also known as hybrid inorganic-organic materials, represent an emerging class of materials that have attracted the imagination of solid-state chemists because MOFs combine unprecedented levels of porosity with a range of other functional properties that occur through the metal moiety and/or the organic ligand. The purpose of this critical review is to give a representative and comprehensive overview of the arising developments in the field of functional metal-organic frameworks, including luminescence, magnetism, and porosity through presenting examples. This review will be of interest to researchers and synthetic chemists attempting to design multifunctional MOFs.

Study on corrosion of metal materials in nitrate molten salts

Science.gov (United States)

Zhai, Wei; Yang, Bo; Li, Maodong; Li, Shiping; Xin, Mingliang; Zhang, Shuanghong; Huang, Guojia

2017-01-01

High temperature molten salts as a heat transfer heat storage medium has been more widely used in the field of concentrated solar thermal power generation. In the thermal heat storage system, metal material stability and performance at high temperatures are of one major limitation in increasing this operating temperature. In this paper, study on corrosion of 321H, 304, 316L, P91 metal materials in modified solar two molten salts. The corrosion kinetics of 304, 316L, 321H, P91 metal material in the modified solar two molten salts at 450°C, 500°C is also investigated. Under the same condition it was found that 304, 321H corroded at a rate of 40% less than P91. Spallation of corrosion products was observed on P91 steel, while no obvious observed on other kinds of stainless steel. Corrosion rates of 304, 321H, and 316L slowly increased with temperature. Oxidation mechanisms little varied with temperature. Corrosion products of metal materials observed at 450°C, 500°C were primarily Fe oxide and Fe, Cr oxide.

Materials safeguards and accountability in the low enriched uranium conversion-fabrication sector of the fuel cycle

International Nuclear Information System (INIS)

Schneider, R.A.; Nilson, R.; Jaech, J.L.

1978-01-01

Today materials accounting in the low enriched conversion-fabrication sector of the LWR fuel cycle is of increased importance. Low enriched uranium is rapidly becoming a precious metal with current dollar values in the range of one dollar per gram comparing with gold and platinum at 7-8 dollars per gram. In fact, people argue that its dollar value exceeds its safeguards value. Along with this increased financial incentive for better material control, the nuclear industry is faced with the impending implementation of international safeguards and increased public attention over its ability to control nuclear materials. Although no quantity of low enriched uranium (LEU) constitutes a practical nuclear explosive, its control is important to international safeguards because of plutonium production or further enrichment to an explosive grade material. The purpose of the paper is to examine and discuss some factors in the area of materials safeguards and accountability as they apply to the low enriched uranium conversion-fabrication sector. The paper treats four main topics: basis for materials accounting; our assessment of the proposed new IAEA requirements; adequacy of current practices; and timing and direction of future modifications

Thermal reliability test of Al-34%Mg-6%Zn alloy as latent heat storage material and corrosion of metal with respect to thermal cycling

International Nuclear Information System (INIS)

Sun, J.Q.; Zhang, R.Y.; Liu, Z.P.; Lu, G.H.

2007-01-01

The purpose of this study is to determine the thermal reliability and corrosion of the Al-34%Mg-6%Zn alloy as a latent heat energy storage material with respect to various numbers of thermal cycles. The differential scanning calorimeter (DSC) analysis technique was applied to the alloy after 0, 50, 500 and 1000 melting/solidification cycles in order to measure the melting temperatures and the latent heats of fusion of the alloy. The containment materials were stainless steel (SS304L), carbon steel (steel C20) in the corrosion tests. The DSC results indicated that the change in melting temperature for the alloy was in the range of 3.06-5.3 K, and the latent heat of fusion decreased 10.98% after 1000 thermal cycles. The results show that the investigated Al-34%Mg-6%Zn alloy has a good thermal reliability as a latent heat energy storage material with respect to thermal cycling for thermal energy storage applications in the long term in view of the small changes in the latent heat of fusion and melting temperature. Gravimetric analysis as mass loss (mg/cm 2 ), corrosion rate (mg/day) and a microscopic or metallographic investigation were performed for corrosion tests and showed that SS304L may be considered a more suitable alloy than C20 in long term thermal storage applications

Cermet materials prepared by combustion synthesis and metal infiltration

Science.gov (United States)

Holt, Joseph B.; Dunmead, Stephen D.; Halverson, Danny C.; Landingham, Richard L.

1991-01-01

Ceramic-metal composites (cermets) are made by a combination of self-propagating high temperature combustion synthesis and molten metal infiltration. Solid-gas, solid-solid and solid-liquid reactions of a powder compact produce a porous ceramic body which is infiltrated by molten metal to produce a composite body of higher density. AlN-Al and many other materials can be produced.

International measures needed to protect metal recycling facilities from radioactive materials

International Nuclear Information System (INIS)

Mattia, M.; Wiener, R.

1999-01-01

In almost every major city and region of every country, there is a recycling facility that is designed to process or consume scrap metal. These same countries will probably have widespread applications of radioactive materials and radiation generating equipment. This material and equipment will have metal as a primary component of its housing or instrumentation. It is this metal that will cause these sources of radioactivity, when lost, stolen or mishandled, to be taken to a metal recycling facility to be sold for the value of the metal. This is the problem that has faced scrap recycling facilities for many years. The recycling industry has spent millions of dollars for installation of radiation monitors and training in identification of radioactive material. It has expended millions more for the disposal of radioactive material that has mistakenly entered these facilities. Action must be taken to prevent this material from entering the conventional recycling process. There are more than 2,300 known incidents of radioactive material found in recycled metal scrap. Worldwide, more than 50 smeltings of radioactive sources have been confirmed. Seven fatal accidents involving uncontrolled radioactive material have also been documented. Hazardous exposures to radioactive material have plagued not just the workers at metal recycling facilities. The families of these workers, including their children, have been exposed to potentially harmful levels of radioactivity. The threat from this material does not stop there. Radioactive material that is not caught at recycling facilities can be melted and the radioactivity has been found in construction materials used to build homes, as well as shovels, fencing material, and furniture offered for sale to the general public. The time has come for the international community to address the issue of the uncontrolled sources of radioactive material. The following are the key points that must be addressed. (i) Identification of sources

Steam water cycle chemistry of liquid metal cooled innovative nuclear power reactors

International Nuclear Information System (INIS)

Yurmanov, Victor; Lemekhov, Vadim; Smykov, Vladimir

2012-09-01

The Federal Target Program (FTP) of Russian Federation 'Nuclear Energy Technologies of the New Generation for 2010-2015 and for Perspective up to 2020' is aimed at development of advanced nuclear energy technologies on the basis of closed fuel cycle with fast reactors. There are advanced fast reactor technologies of the 4. generation with liquid metal cooled reactors. Development stages of maturity of fast sodium cooled reactor technology in Russia includes experimental reactors BR-5/10 (1958-2002) and BOR-60 (since 1969), nuclear power plants (NPPs) with BN-350 (1972-1999), BN-600 (since 1980), BN-800 (under construction), BN-1200 (under development). Further stage of development of fast sodium cooled reactor technology in Russia is commercialization. Lead-bismuth eutectic fast reactor technology has been proven at industrial scale for nuclear submarines in former Soviet Union. Lead based technology is currently under development and need for experimental justification. Current status and prospects of State Corporation 'Rosatom' participation in GIF activities was clarified at the 31. Meeting of Policy Group of the International Forum 'Generation-IV', Moscow, May 12-13, 2011. In June, 2010, 'Rosatom' joined the Sodium Fast Reactor Arrangement as an authorized representative of the Russian Government. It was also announced the intention of 'Rosatom' to sign the Memorandum on Lead Fast Reactor based on Russia's experience with lead-bismuth and lead cooled fast reactors. In accordance with the above FTP some innovative liquid metal cooled reactors of different design are under development in Russia. Gidropress, well known as WER designer, develops innovative lead-bismuth eutectic cooled reactor SVBR-100. NIKIET develops innovative lead cooled reactor BRESTOD-300. Some other nuclear scientific centres are also involved in this activity, e.g. Research and Development Institute for Power Engineering (RDIPE). Optimum

Interactions between heavy metals and photosynthetic materials studied by optical techniques.

Science.gov (United States)

Ventrella, Andrea; Catucci, Lucia; Piletska, Elena; Piletsky, Sergey; Agostiano, Angela

2009-11-01

In this work studies on rapid inhibitory interactions between heavy metals and photosynthetic materials at different organization levels were carried out by optical assay techniques, investigating the possibility of applications in the heavy metal detection field. Spinach chloroplasts, thylakoids and Photosystem II proteins were employed as biotools in combination with colorimetric assays based on dichlorophenol indophenole (DCIP) photoreduction and on fluorescence emission techniques. It was found that copper and mercury demonstrated a strong and rapid photosynthetic activity inhibition, that varied from proteins to membranes, while other metals like nickel, cobalt and manganese produced only slight inhibition effects on all tested photosynthetic materials. By emission measurements, only copper was found to rapidly influence the photosynthetic material signals. These findings give interesting information about the rapid effects of heavy metals on isolated photosynthetic samples, and are in addition to the literature data concerning the effects of growth in heavy metal enriched media.

Comparative study of material loss at the taper interface in retrieved metal-on-polyethylene and metal-on-metal femoral components from a single manufacturer.

Science.gov (United States)

Bills, Paul; Racasan, Radu; Bhattacharya, Saugatta; Blunt, Liam; Isaac, Graham

2017-08-01

There have been a number of reports on the occurrence of taper corrosion and/or fretting and some have speculated on a link to the occurrence of adverse local tissue reaction specifically in relation to total hip replacement which have a metal-on-metal bearing. As such a study was carried out to compare the magnitude of material loss at the taper in a series of retrieved femoral heads used in metal-on-polyethylene bearings with that in a series of retrieved heads used in metal-on-metal bearings. A total of 36 metal-on-polyethylene and 21 metal-on-metal femoral components were included in the study all of which were received from a customer complaint database. Furthermore, a total of nine as-manufactured femoral components were included to provide a baseline for characterisation. All taper surfaces were assessed using an established corrosion scoring method and measurements were taken of the female taper surface using a contact profilometry. In the case of metal-on-metal components, the bearing wear was also assessed using coordinate metrology to determine whether or not there was a relationship between bearing and taper material loss in these cases. The study found that in this cohort the median value of metal-on-polyethylene taper loss was 1.25 mm 3 with the consequent median value for metal-on-metal taper loss being 1.75 mm 3 . This study also suggests that manufacturing form can result in an apparent loss of material from the taper surface determined to have a median value of 0.59 mm 3 . Therefore, it is clear that form variability is a significant confounding factor in the measurement of material loss from the tapers of femoral heads retrieved following revision surgery.

Diel cycle of iron, aluminum and other heavy metals in a volcano watershed in northern Taiwan

Science.gov (United States)

Kao, S.

2013-12-01

It is well known that heavy metals in surface water show diel (24-hr) changes in concentrations due to diel biogeochemical cycle. Accordingly, it is important to have a better sampling policy for monitoring the environmental impact of heavy metals of surface water, especially volcanic and mining areas. This study investigated Tatun Volcano watershed in northern Taiwan with a 24-h sampling operation to explore the diel cycle of arsenic concentrations and discuss on the corresponding biogeochemical processes. According to the previous studies, solar energy is the main factor of diel cycles, which could have strong effects on temperature, pH, dissolved oxygen, and many other water qualities. These changes produce a series of chain reactions and finally result in the change of heavy metal concentrations. In general, diel cycle of dissolved oxygen is dominated by metabolism of aquatic plants and sunlight photoreduction in acidic stream water; therefore, the Fe and Al contents would be accordingly changed. In addition, the concentrations of heavy metals will be simultaneously modified due to the high adsorption capacity of Fe and Al hydroxides. In this study, the results of hydro chemical analysis show that creek water is characterized by higher temperature, low pH value (3.0-4.5) and high SO4content(60-400 ppm) due to the mixing of hot spring. That the pH dramatically drops in the noon demonstrates that pH is highly dependent on photoreduction. This can be confirmed by the opposite trend of Fe concentration. The high Fe content in the noon also demonstrates that the precipitation of Fe hydroxides is not dominant in the day time and Fe is mainly in dissolved and/or colloid forms. Under the situation, heavy metals are supposed to have a similar trend with Fe. However, arsenic, aluminum and rare earth elements show a quite different diel cycle from Fe and other heavy metals. It concludes that arsenic and rare earth elements may be adsorbed by Al hydroxides instead of Fe

Wear Resistance of 3D Printing Resin Material Opposing Zirconia and Metal Antagonists.

Science.gov (United States)

Park, Ji-Man; Ahn, Jin-Soo; Cha, Hyun-Suk; Lee, Joo-Hee

2018-06-20

3D printing offers many advantages in dental prosthesis manufacturing. This study evaluated the wear resistance of 3D printing resin material compared with milling and conventional resin materials. Sixty substrate specimens were prepared with three types of resin materials: 3D printed resin, milled resin, and self-cured resin. The 3D printed specimens were printed at a build angle of 0° and 100 μm layer thickness by digital light processing 3D printing. Two kinds of abraders were made of zirconia and CoCr alloy. The specimens were loaded at 5 kg for 30,000 chewing cycles with vertical and horizontal movements under thermocycling condition. The 3D printed resin did not show significant difference in the maximal depth loss or the volume loss of wear compared to the milled and the self-cured resins. No significant difference was revealed depending on the abraders in the maximal depth loss or the volume loss of wear. In SEM views, the 3D printed resin showed cracks and separation of inter-layer bonds when opposing the metal abrader. The results suggest that the 3D printing using resin materials provides adequate wear resistance for dental use.

Additive manufacturing of metals

International Nuclear Information System (INIS)

Herzog, Dirk; Seyda, Vanessa; Wycisk, Eric; Emmelmann, Claus

2016-01-01

Additive Manufacturing (AM), the layer-by layer build-up of parts, has lately become an option for serial production. Today, several metallic materials including the important engineering materials steel, aluminium and titanium may be processed to full dense parts with outstanding properties. In this context, the present overview article describes the complex relationship between AM processes, microstructure and resulting properties for metals. It explains the fundamentals of Laser Beam Melting, Electron Beam Melting and Laser Metal Deposition, and introduces the commercially available materials for the different processes. Thereafter, typical microstructures for additively manufactured steel, aluminium and titanium are presented. Special attention is paid to AM specific grain structures, resulting from the complex thermal cycle and high cooling rates. The properties evolving as a consequence of the microstructure are elaborated under static and dynamic loading. According to these properties, typical applications are presented for the materials and methods for conclusion.

Metallic 1T phase MoS2 nanosheets as supercapacitor electrode materials.

Science.gov (United States)

Acerce, Muharrem; Voiry, Damien; Chhowalla, Manish

2015-04-01

Efficient intercalation of ions in layered materials forms the basis of electrochemical energy storage devices such as batteries and capacitors. Recent research has focused on the exfoliation of layered materials and then restacking the two-dimensional exfoliated nanosheets to form electrodes with enhanced electrochemical response. Here, we show that chemically exfoliated nanosheets of MoS2 containing a high concentration of the metallic 1T phase can electrochemically intercalate ions such as H(+), Li(+), Na(+) and K(+) with extraordinary efficiency and achieve capacitance values ranging from ∼400 to ∼700 F cm(-3) in a variety of aqueous electrolytes. We also demonstrate that this material is suitable for high-voltage (3.5 V) operation in non-aqueous organic electrolytes, showing prime volumetric energy and power density values, coulombic efficiencies in excess of 95%, and stability over 5,000 cycles. As we show by X-ray diffraction analysis, these favourable electrochemical properties of 1T MoS2 layers are mainly a result of their hydrophilicity and high electrical conductivity, as well as the ability of the exfoliated layers to dynamically expand and intercalate the various ions.

New method of thermal cycling stability test of phase change material

Directory of Open Access Journals (Sweden)

Putra Nandy

2017-01-01

Full Text Available Phase Change Material (PCM is the most promising material as thermal energy storage nowadays. As thermal energy storage, examination on endurance of material for long-term use is necessary to be carried out. Therefore, thermal cycling test is performed to ensure thermal stability of PCM. This study have found a new method on thermal cycling test of PCM sample by using thermoelectric as heating and cooling element. RT 22 HC was used as PCM sample on this thermal cycling test. The new method had many advantages compared to some references of the same test. It just needed a small container for PCM sample. The thermoelectric could release heat to PCM sample and absorb heat from PCM sample uniformly, respectively, was called as heating and cooling process. Hence, thermoelectric had to be supported by a relay control device to change its polarity so it could heat and cool PCM sample alternately and automatically. On the other hand, the thermoelectric was cheap, easy to be found and available in markets. It can be concluded that new method of thermal cycling test by using thermoelectric as source of heating and cooling can be a new reference for performing thermal cycling test on PCM.

Leading research on super metal. 2. Aluminium materials; Super metal no sendo kenkyu. 2. Ogata sozai (aluminium kei)

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-03-01

Aluminum materials were surveyed to improve aluminum materials drastically so as to play an important role as prospective materials in response to the changing social environment. Aluminum materials have become the following metal materials to iron materials due to their light weight, durability, and profitability. Based on their merits and demerits, it was made clear how the aluminum materials contribute to the future resource saving, energy saving, and global environmental protection. Review was made on the two research and development themes which contribute to the creation of super metals. Hence, the themes proposed are focused on the creation of new aluminum mill products with ultra fine grain structure using very low temperature processing and on the creation of super-formability aluminum alloy sheets by advanced texture control using processing which can enhance the shearing stress. Results of the research and development are expected to provide wide applicability for other metals, ceramics, and polymers. 433 refs., 315 figs., 56 tabs.

Proposed industrial recovered materials utilization targets for the metals and metal-products industry

Energy Technology Data Exchange (ETDEWEB)

None

1979-05-01

The introductory chapter provides a discussion of the factors that affect the recovery and reuse of secondary materials and the competition between the primary and secondary metals industries. It discusses these industries in terms of resource characteristics, industry technology, pollution control requirements, market structure, the economics of recycling, and the issues involved in econometrically estimating scrap supply response behavior. It further presents the methodology established by DOE for the metals, textiles, rubber, and pulp and paper industries. The areas in which government policies might have a significant impact on the utilization of primary and secondary metals and on any recycling targets between now and 1987 are noted. Chapter 3 presents general profiles for the major industrial segments comprising SIC 33. The profiles include such topics as industry structure, process technology, materials and recycling flow, and future trends. Chapter 4 specifically covers the evaluation of recycling targets for the ferrous, aluminum, copper, zinc, and lead industries. (MCW)

Computational dynamics of laser alloyed metallic materials for improved corrosion performance: computational dynamics of laser alloyed metallic materials

CSIR Research Space (South Africa)

Fatoba, OS

2016-04-01

Full Text Available Laser alloying is a material processing method which utilizes the high power density available from defocused laser beam to melt both metal coatings and a part of the underlying substrate. Since melting occur solitary at the surface, large...

FBR metallic materials test manual (English version)

International Nuclear Information System (INIS)

Odaka, Susumu; Kato, Shoichi; Yoshida, Eiichi

2003-06-01

For the development of the fast breeder reactor, this manual describes the method of in-air and in-sodium material tests and the method of organization the data. This previous manual has revised in accordance with the revision of Japanese Industrial Standard (JIS) and the conversion to the international unit. The test methods of domestic committees such as the VAMAS (Versailles Project on Advanced Materials and Standards) workshop were also refereed. The material test technologies accumulated in this group until now were also incorporated. This English version was prepared in order to provide more engineers with the FBR metallic materials test manual. (author)

Evaluating the Aspect of Nuclear Material in Fuel Cycles

Energy Technology Data Exchange (ETDEWEB)

Takagi, Shunsuke; Pickett, Susan; Oda, Takuji; Choi, Jor-Shan; Kuno, Yusuke; Takana, Satoru [Department of Nuclear Engineering and Management, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8685 (Japan); Nagasaki, Shinya [Nuclear Professional School, The University of Tokyo (Japan)

2009-06-15

The increasing number of countries that wish to introduce nuclear power plants raises attention to proliferation resistance in nuclear power plants, and nuclear fuel cycle facilities. In order to achieve adequate proliferation resistance, it is important to evaluate it and to construct effective international institutional frameworks as well as technologies involving high level of proliferation resistance. Although some methods have been proposed for evaluation of the proliferation resistance, their validities have not been investigated in detail. In the present paper, therefore, we compare some of the proposed methodologies. It is essential to detect the abuse or diversion of nuclear material before the nuclear explosive device can be manufactured in order to prevent proliferation. The time needed for the detection of material primary depends on the safeguards that the country applies, and the time needed for fabrication mainly depends on the attributes of the nuclear material. Hence, we divided the proliferation resistance into two parts: the level of safeguards and the material. For examination of evaluation methods such as the one proposed by Charlton [1] or the figure of merit (FOM) [2], sensitivity analysis was performed on weighting factors and scenarios. The validity and characteristics of each method were discussed, focusing on the applicability of each method to the assessment of multi-national approaches such as GNEP. [1] W. S. Charlton, R. L. LeBouf, C. Gariazzo, D. G. Ford, C. Beard, S. Landeberger, M. Whitaker, 'Proliferation resistance assessment methodology for nuclear fuel cycles', Nuclear Technology, 157, 1 (2007). [2] C.G. Bathke et al, 'An assessment of the proliferation resistance of materials in advanced nuclear fuel cycles', 8. International Conference on Facility Operations (2008). (authors)

Dendrite-Free Sodium-Metal Anodes for High-Energy Sodium-Metal Batteries.

Science.gov (United States)

Sun, Bing; Li, Peng; Zhang, Jinqiang; Wang, Dan; Munroe, Paul; Wang, Chengyin; Notten, Peter H L; Wang, Guoxiu

2018-05-31

Sodium (Na) metal is one of the most promising electrode materials for next-generation low-cost rechargeable batteries. However, the challenges caused by dendrite growth on Na metal anodes restrict practical applications of rechargeable Na metal batteries. Herein, a nitrogen and sulfur co-doped carbon nanotube (NSCNT) paper is used as the interlayer to control Na nucleation behavior and suppress the Na dendrite growth. The N- and S-containing functional groups on the carbon nanotubes induce the NSCNTs to be highly "sodiophilic," which can guide the initial Na nucleation and direct Na to distribute uniformly on the NSCNT paper. As a result, the Na-metal-based anode (Na/NSCNT anode) exhibits a dendrite-free morphology during repeated Na plating and striping and excellent cycling stability. As a proof of concept, it is also demonstrated that the electrochemical performance of sodium-oxygen (Na-O 2 ) batteries using the Na/NSCNT anodes show significantly improved cycling performances compared with Na-O 2 batteries with bare Na metal anodes. This work opens a new avenue for the development of next-generation high-energy-density sodium-metal batteries. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

An overview on the Bauschinger effect in metallic materials

International Nuclear Information System (INIS)

Wang Yanfeng; Li Cong; Ling Xuyu; Shen Baoluo; Gao Shengji

2002-01-01

The Bauschinger effect in metallic materials including f.c.c. (face-centered cubic) and b.c.c. (body-centered cubic) materials such as pure alloys, casting alloys, copper alloys, aluminium alloys and metal matrix composite materials, and h.c.p. (hexagonal close packed) materials such as zirconium alloys and titanium alloys have been summarized comprehensively. The mechanism of Bauschinger effect is reviewed from the point of dislocation theory and internal stress (or back stress) that is responsible for the effect. Based upon these theories, the methods for calculating internal stress and models for simulating the effect are described briefly, which could explain the effect quantitatively. Finally, the measures to reduce or eliminate the effect have been pointed out, along with the issues to be researched in the future

Tool-life prediction under multi-cycle loading during metal forming: a feasibility study

Directory of Open Access Journals (Sweden)

Hu Yiran

2015-01-01

Full Text Available In the present research, the friction and wear behaviour of a hard coating were studied by using ball-on-disc tests to simulate the wear process of the coated tools for sheet metal forming process. The evolution of the friction coefficient followed a typical dual-plateau pattern, i.e. at the initial stage of sliding, the friction coefficient was relatively low, followed by a sharp increase due to the breakdown of the coatings after a certain number of cyclic dynamic loadings. This phenomenon was caused by the interactive response between the friction and wear from a coating tribo-system, which is often neglected by metal forming researchers, and constant friction coefficient values are normally used in the finite element (FE simulations to represent the complex tribological nature at the contact interfaces. Meanwhile, most of the current FE simulations consider single-cycle loading processes, whereas many metal-forming operations are conducted in a form of multi-cycle loading. Therefore, a novel friction/wear interactive friction model was developed to, simultaneously, characterise the evolutions of friction coefficient and the remaining thickness of the coating layer, to enable the wear life of coated tooling to be predicted. The friction model was then implemented into the FE simulation of a sheet metal forming process for feasibility study.

Design, Synthesis and Characterization of Functional Metal-Organic Framework Materials

KAUST Repository

Alamer, Badriah

2015-06-01

Over the past few decades, vast majority of industrial and academic research throughout the world has witnessed the emergence of materials that can serve as ideal candidates for potential utility in desired applications, and these materials are known as Metal Organic Framework (MOFs). This exceptional new family of porous materials is fabricated by linkage of metal ions or clusters and organic linkers via strong bonds. MOFs have been awarded with remarkable interest and widely studied due to their inherent structural methodology (e.g. use of various metals, expanded library of organic building blocks with different geometry and functionality particularly frameworks designed from carboxylate organic linkers) and unquestionably unique structural and chemical features for many practical applications. (i.e. gas storage/separation, catalysis, drug delivery etc). Simply, metal organic frameworks epitomize the beauty of porous chemical structures. From a design perspective, the introduction of the Molecular Building Block (MBB) approach is actively being pursued pathway by researchers toward the construction of MOFs by employing inorganic building blocks and organic linkers and taking advantage of not only their multiple coordination modes and geometries but also the way in which they are reticulated to generate final framework. In this thesis, research studies will be directed toward (i) the investigation of the relationship between experimental parameters and synthesis of well-known fcu –MOF, (ii) rational design and synthesis of new rare earth (RE) based MOFs, (ii) isoreticular materials based on particular MBB ([M3O(RCO2)6]), M= p-and d-block metals, and (iv) zeolite- like metal organic framework assembled from single-metal ion based MBB ([MN2(CO2)4]) via 2-, 3-,and 4-connected organic linkers. Consequently, the porosity, chemical and thermal stability, and gas sorption properties will be evaluated and detailed.

The US Liquid-Metal Reactor Program - overview and status

International Nuclear Information System (INIS)

Quinn, J.E.; Gyorey, G.L.; Salerno, L.N.

1992-01-01

The US Advanced Liquid-Metal Reactor (ALMR) Program has three major elements being developed in an integrated fashion to produce a system meeting the US long-term nuclear energy needs. Reactor design, one of those elements, is the focus of this paper. The other two elements, the integral fast reactor metal-fuel cycle and the light water reactor (LWR) spent-fuel actinide recycle, will be addressed in companion papers. The ALMR is adaptable to multiple missions with few modifications such as the core arrangements. The missions identified to date are (a) the extension of the existing uranium resources through breeding and highly efficient uranium utilization, (b) the recycle and utilization of the long-life actinides in LWR spent fuel as fissile material for the ALMR, and (c) the conversion of excess weapons fissil material into electricity. In addition to these missions, the reactor design is adaptable to either the metal-fuel cycle or the oxide fuel cycle

Hollow carbon sphere/metal oxide nanocomposites anodes for lithium-ion batteries

International Nuclear Information System (INIS)

Wenelska, K.; Ottmann, A.; Schneider, P.; Thauer, E.; Klingeler, R.; Mijowska, E.

2016-01-01

HCS (Hollow carbon spheres) covered with metal oxide nanoparticles (SnO_2 and MnO_2, respectively) were successfully synthesized and investigated regarding their potential as anode materials for lithium-ion batteries. Raman spectroscopy shows a high degree of graphitization for the HCS host structure. The mesoporous nature of the nanocomposites is confirmed by Brunauer–Emmett–Teller analysis. For both metal oxides under study, the metal oxide functionalization of HCS yields a significant increase of electrochemical performance. The charge capacity of HCS/SnO_2 is 370 mA hg"−"1 after 45 cycles (266 mA hg"−"1 in HCS/MnO_2) which clearly exceeds the value of 188 mA hg"−"1 in pristine HCS. Remarkably, the data imply excellent long term cycling stability after 100 cycles in both cases. The results hence show that mesoporous HCS/metal oxide nanocomposites enable exploiting the potential of metal oxide anode materials in Lithium-ion batteries by providing a HCS host structure which is both conductive and stable enough to accommodate big volume change effects. - Highlights: • Strategy to synthesize hollow carbon spheres decorated by metal oxides nanoparticles. • High-performance of HCS/MOx storage as mesoporous hybrid material. • The results hence demonstrate high electrochemical activity of the HCS/MOx.

Biodegradable Materials and Metallic Implants-A Review.

Science.gov (United States)

Prakasam, Mythili; Locs, Janis; Salma-Ancane, Kristine; Loca, Dagnija; Largeteau, Alain; Berzina-Cimdina, Liga

2017-09-26

Recent progress made in biomaterials and their clinical applications is well known. In the last five decades, great advances have been made in the field of biomaterials, including ceramics, glasses, polymers, composites, glass-ceramics and metal alloys. A variety of bioimplants are currently used in either one of the aforesaid forms. Some of these materials are designed to degrade or to be resorbed inside the body rather than removing the implant after its function is served. Many properties such as mechanical properties, non-toxicity, surface modification, degradation rate, biocompatibility, and corrosion rate and scaffold design are taken into consideration. The current review focuses on state-of-the-art biodegradable bioceramics, polymers, metal alloys and a few implants that employ bioresorbable/biodegradable materials. The essential functions, properties and their critical factors are discussed in detail, in addition to their challenges to be overcome.

Material Cycles and Chemicals: Dynamic Material Flow Analysis of Contaminants in Paper Recycling

DEFF Research Database (Denmark)

Pivnenko, Kostyantyn; Laner, David; Astrup, Thomas Fruergaard

2016-01-01

material source-segregation and collection was the least effective strategy for reducing chemical contamination, if the overall recycling rates should be maintained at the current level (approximately 70% for Europe). The study provides a consistent approach for evaluating contaminant levels in material......This study provides a systematic approach for assessment of contaminants in materials for recycling. Paper recycling is used as an illustrative example. Three selected chemicals, bisphenol A (BPA), diethylhexyl phthalate (DEHP) and mineral oil hydrocarbons (MOHs), are evaluated within the paper...... cycle. The approach combines static material flow analysis (MFA) with dynamic material and substance flow modeling. The results indicate that phasing out of chemicals is the most effective measure for reducing chemical contamination. However, this scenario was also associated with a considerable lag...

Investigations on the metabolism of metals in decapod crustaceas in relation with moulting cycles and reproduction

International Nuclear Information System (INIS)

Martin, J.-L.M.

1975-07-01

A study of the metabolism of metals was carried out in decapod crustaceas; it showed that it was subject to cyclic variations during the life of the animals, closely correlated with growth moults. The metabolism of metals was also considered in its relations with reproduction, especially oogenesis and spermatogenesis, and embryonic development. In relation with moult, various factors playing a role on metal metabolism were investigated: role of metals in the organism, fasting and nutrition cycles and biochemical reserves, physico-chemical form of the metal and ultrastructure of uptake surfaces. The histological and histochemical aspects of the uptake of a number of metals were studied as well as inter-metallic and inter-organic relationships [fr

Determination of the mechanism and extent of surface degradation in Ni-based cathode materials after repeated electrochemical cycling

Directory of Open Access Journals (Sweden)

Sooyeon Hwang

2016-09-01

Full Text Available We take advantage of scanning transmission electron microscopy and electron energy loss spectroscopy to investigate the changes in near-surface electronic structure and quantify the degree of local degradation of Ni-based cathode materials with the layered structure (LiNi0.8Mn0.1Co0.1O2 and LiNi0.4Mn0.3Co0.3O2 after 20 cycles of delithiation and lithiation. Reduction of transition metals occurs in the near-surface region of cathode materials: Mn is the major element to be reduced in the case of relatively Mn-rich composition, while reduction of Ni ions is dominant in Ni-rich materials. The valences of Ni and Mn ions are complementary, i.e., when one is reduced, the other is oxidized in order to maintain charge neutrality. The depth of degradation zone is found to be much deeper in Ni-rich materials. This comparative analysis provides important insights needed for the devising of new cathode materials with high capacity as well as long lifetime.

41 CFR 109-45.1003 - Recovery of silver from precious metals bearing materials.

Science.gov (United States)

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Recovery of silver from precious metals bearing materials. 109-45.1003 Section 109-45.1003 Public Contracts and Property Management... of Precious Metals § 109-45.1003 Recovery of silver from precious metals bearing materials. The...

Simulated first operating campaign for the Integral Fast Reactor fuel cycle demonstration

International Nuclear Information System (INIS)

Goff, K.M.; Mariani, R.D.; Benedict, R.W.; Park, K.H.; Ackerman, J.P.

1993-01-01

This report discusses the Integral Fast Reactor (IFR) which is an innovative liquid-metal-cooled reactor concept that is being developed by Argonne National Laboratory. It takes advantage of the properties of metallic fuel and liquid-metal cooling to offer significant improvements in reactor safety, operation, fuel cycle-economics, environmental protection, and safeguards. Over the next few years, the IFR fuel cycle will be demonstrated at Argonne-West in Idaho. Spent fuel from the Experimental Breeder Reactor II (EBR-II) win be processed in its associated Fuel Cycle Facility (FCF) using a pyrochemical method that employs molten salts and liquid metals in an electrorefining operation. As part of the preparation for the fuel cycle demonstration, a computer code, PYRO, was developed at Argonne to model the electrorefining operation using thermodynamic and empirical data. This code has been used extensively to evaluate various operating strategies for the fuel cycle demonstration. The modeled results from the first operating campaign are presented. This campaign is capable of processing more than enough material to refuel completely the EBR-II core

Morphology evolution and nanostructure of chemical looping transition metal oxide materials upon redox processes

International Nuclear Information System (INIS)

Qin, Lang; Cheng, Zhuo; Guo, Mengqing; Fan, Jonathan A.; Fan, Liang-Shih

2017-01-01

Transition metal are heavily used in chemical looping technologies because of their high oxygen carrying capacity and high thermal reactivity. These oxygen activities result in the oxide formation and oxygen vacancy formation that affect the nanoscale crystal phase and morphology within these materials and their subsequent bulk chemical behavior. In this study, two selected earlier transition metals manganese and cobalt as well as two selected later transition metals copper and nickel that are important to chemical looping reactions are investigated when they undergo cyclic redox reactions. We found Co microparticles exhibited increased CoO impurity presence when oxidized to Co_3O_4 upon cyclic oxidation; CuO redox cycles prefer to be limited to a reduced form of Cu_2O and an oxidized form of CuO; Mn microparticles were oxidized to a mixed phases of MnO and Mn_3O_4, which causes delamination during oxidation. For Ni microparticles, a dense surface were observed during the redox reaction. The atomistic thermodynamics methods and density functional theory (DFT) calculations are carried out to elucidate the effect of oxygen dissociation and migration on the morphological evolution of nanostructures during the redox processes. Our results indicate that the earlier transition metals (Mn and Co) tend to have stronger interaction with O_2 than the later transition metals (Ni and Cu). Also, our modified Brønsted−Evans−Polanyi (BEP) relationship for reaction energies and total reaction barriers reveals that reactions of earlier transition metals are more exergonic and have lower oxygen dissociation barriers than those of later transition metals. In addition, it was found that for these transition metal oxides the oxygen vacancy formation energies increase with the depth. The oxide in the higher oxidation state of transition metal has lower vacancy formation energy, which can facilitate forming the defective nanostructures. The fundamental understanding of these metal

Ultra-small Fe3O4 nanocrystals decorated on 2D graphene nanosheets with excellent cycling stability as anode materials for lithium ion batteries

International Nuclear Information System (INIS)

Ren, Manman; Yang, Mingzhi; Liu, Weiliang; Li, Mei; Su, Liwei; Qiao, Congde; Wu, Xianbin; Ma, Houyi

2016-01-01

Graphical abstract: Ultra-small Fe 3 O 4 nanocrystals decorated on 2D graphene nanosheets with excellent cycling stability as anode materials for lithium ion batteries Manman Ren, Mingzhi Yang, Weiliang Liu, Mei Li, Liwei Su, Congde Qiao, Xianbin Wu, Houyi Ma Ultra-small Fe 3 O 4 nanocrystals/graphene nanosheets composites demonstrate excellent long-term cycling stability at high-rate. - Abstract: Ultra-small Fe 3 O 4 nanocrystals (NCs)/garphene nanosheets (GNSs) composites have been synthesized through a facile gel-like film (GF) assisted method in this work. Fe 3 O 4 NCs with particle size ∼10 nm homogeneously dispersed on 2D GNSs. Profiting from the ultra-small Fe 3 O 4 NCs and GNSs, the composites demonstrate superior long-term and high-rate performance as anode materials for lithium ion batteries. Even at the current density of 5 A g −1 , the reversible capacity still maintains 323.4 mAh g −1 after 700 cycles. This work might enlighten us on exploring preferable strategies to develop advanced metal oxides NCs/GNSs composites anode materials for lithium ion batteries or other energy storage devices.

Corrosion of metallic materials. Dry corrosion, aqueous corrosion and corrosion by liquid metal, methods of protection

International Nuclear Information System (INIS)

Helie, Max

2015-01-01

This book is based on a course on materials given in an engineering school. The author first gives an overview of metallurgy issues: metallic materials (pure metals, metallic alloys), defects of crystal lattices (point defects, linear defects or dislocations), equilibrium diagrams, steels and cast, thermal processing of steels, stainless steels, aluminium and its alloys, copper and its alloys. The second part addresses the properties and characterization of surfaces and interfaces: singularity of a metal surface, surface energy of a metal, energy of grain boundaries, adsorption at a material surface, metal-electrolyte interface, surface oxide-electrolyte interface, techniques of surface analysis. The third chapter addresses the electrochemical aspects of corrosion: description of the corrosion phenomenon, free enthalpy of a compound and free enthalpy of a reaction, case of dry corrosion (thermodynamic aspect, Ellingham diagram, oxidation mechanisms, experimental study, macroscopic modelling), case of aqueous corrosion (electrochemical thermodynamics and kinetics, experimental determination of corrosion rate). The fourth part addresses the different forms of aqueous corrosion: generalized corrosion (atmospheric corrosion, mechanisms and tests), localized corrosion (galvanic, pitting, cracking, intergranular, erosion and cavitation), particular cases of stress cracking (stress corrosion, fatigue-corrosion, embrittlement by hydrogen), and bi-corrosion (of non alloyed steels, of stainless steels, and of aluminium and copper alloys). The sixth chapter addresses the struggle and the protection against aqueous corrosion: methods of prevention, scope of use of main alloys, geometry-based protection of pieces, use of corrosion inhibitors, use of organic or metallic coatings, electrochemical protection. The last chapter proposes an overview of corrosion types in industrial practices: in the automotive industry, in the oil industry, in the aircraft industry, and in the

Anthropogenic Cycles of Rare Earth Elements

Science.gov (United States)

Du, X.; Graedel, T. E.

2009-12-01

This research will develop quantitatively resolved anthropogenic cycles and in-use stocks for the rare earth metals specifically cerium, lanthanum and dysprosium in Japan, China, and the U.S. for the year of 2007. Rare earth elements (REE) is a group of 17 scare metals widely used in a growing number of emerging technologies and have been in high demand for emerging technologies as raw materials during past the three decades. New market participants from newly industrializing countries, primarily China, have had strong impacts on the demand of share. Consequently, the importance to sustain a reliable, steady, uninterrupted supply on global market triggered comprehensive research to recognize and understand the life cycles of rare earths. Moreover, because China plays a dominant role in mining production since 1990, it requires the assessment for the countries, which are almost completely dependent on imports from China with respect to rare earth resources. The study aims to analyze the flows and stocks of rare earth elements individually as elemental form in spite of their natural geological co-occurrence and mixed composition in applications. By applying the method of Material Flow Analysis (MFA) work has been done on evaluating current and historical flows of specific technologically significant materials, for example, copper, zinc, nickel, etc., determining the stocks available in different types of reservoirs (e.g., lithosphere, in-use) and the flows among the reservoirs, developing scenarios of possible futures of metal use, and assessing the environmental and policy implications of the results. Therefore, REE as a new target deserves inclusion because of its potential demand-supply conflict and importance to secure the competitive advantage of technical innovation in future. This work will generate a quantitatively resolved anthropogenic life cycle and in-use stocks for REE for the main target countries for a chosen year, 2007, providing flows and stocks from

Fabrication of ultrahigh density metal-cell-metal crossbar memory devices with only two cycles of lithography and dry-etch procedures

KAUST Repository

Zong, Baoyu

2013-05-20

A novel approach to the fabrication of metal-cell-metal trilayer memory devices was demonstrated by using only two cycles of lithography and dry-etch procedures. The fabricated ultrahigh density crossbar devices can be scaled down to ≤70 nm in half-pitch without alignment issues. Depending on the different dry-etch mechanisms in transferring high and low density nanopatterns, suitable dry-etch angles and methods are studied for the transfer of high density nanopatterns. Some novel process methods have also been developed to eliminate the sidewall and other conversion obstacles for obtaining high density of uniform metallic nanopatterns. With these methods, ultrahigh density trilayer crossbar devices (∼2 × 1010 bit cm-2-kilobit electronic memory), which are composed of built-in practical magnetoresistive nanocells, have been achieved. This scalable process that we have developed provides the relevant industries with a cheap means to commercially fabricate three-dimensional high density metal-cell-metal nanodevices. © 2013 IOP Publishing Ltd.

Biodegradable Materials and Metallic Implants—A Review

Science.gov (United States)

Prakasam, Mythili; Locs, Janis; Salma-Ancane, Kristine; Loca, Dagnija; Largeteau, Alain; Berzina-Cimdina, Liga

2017-01-01

Recent progress made in biomaterials and their clinical applications is well known. In the last five decades, great advances have been made in the field of biomaterials, including ceramics, glasses, polymers, composites, glass-ceramics and metal alloys. A variety of bioimplants are currently used in either one of the aforesaid forms. Some of these materials are designed to degrade or to be resorbed inside the body rather than removing the implant after its function is served. Many properties such as mechanical properties, non-toxicity, surface modification, degradation rate, biocompatibility, and corrosion rate and scaffold design are taken into consideration. The current review focuses on state-of-the-art biodegradable bioceramics, polymers, metal alloys and a few implants that employ bioresorbable/biodegradable materials. The essential functions, properties and their critical factors are discussed in detail, in addition to their challenges to be overcome. PMID:28954399

Exploring the mechanical strength of additively manufactured metal structures with embedded electrical materials

Energy Technology Data Exchange (ETDEWEB)

Li, J., E-mail: J.Li5@lboro.ac.uk; Monaghan, T.; Masurtschak, S.; Bournias-Varotsis, A.; Friel, R.J.; Harris, R.A.

2015-07-15

Ultrasonic Additive Manufacturing (UAM) enables the integration of a wide variety of components into solid metal matrices due to the process induced high degree of metal matrix plastic flow at low bulk temperatures. Exploitation of this phenomenon allows the fabrication of previously unobtainable novel engineered metal matrix components. The feasibility of directly embedding electrical materials within UAM metal matrices was investigated in this work. Three different dielectric materials were embedded into UAM fabricated aluminium metal-matrices with, research derived, optimal processing parameters. The effect of the dielectric material hardness on the final metal matrix mechanical strength after UAM processing was investigated systematically via mechanical peel testing and microscopy. It was found that when the Knoop hardness of the dielectric film was increased from 12.1 HK/0.01 kg to 27.3 HK/0.01 kg, the mechanical peel testing and linear weld density of the bond interface were enhanced by 15% and 16%, respectively, at UAM parameters of 1600 N weld force, 25 µm sonotrode amplitude, and 20 mm/s welding speed. This work uniquely identified that the mechanical strength of dielectric containing UAM metal matrices improved with increasing dielectric material hardness. It was therefore concluded that any UAM metal matrix mechanical strength degradation due to dielectric embedding could be restricted by employing a dielectric material with a suitable hardness (larger than 20 HK/0.01 kg). This result is of great interest and a vital step for realising electronic containing multifunctional smart metal composites for future industrial applications.

Environmental Fatigue of Metallic Materials in Nuclear Power Plants - A Review of Korean Test Programs

Energy Technology Data Exchange (ETDEWEB)

Jang, Changheul; Jang, Hun; Hong, Jongdae [KAIST, Daejeon (Korea, Republic of); Cho, Hyunchul [Doosan Heavy Industry and Construction, Changwon (Korea, Republic of); Kim, Tae Soon; Lee, Jaegon [KHNP, Daejeon (Korea, Republic of)

2013-12-15

Environmental fatigue of the metallic components in light water reactors has been the subject of extensive research and regulatory interest in Korea and abroad. Especially, it was one of the key domestic issues for the license renewal of operating reactors and licensing of advanced reactors during the early 2000s. To deal with the environmental fatigue issue domestically, a systematic test program has been initiated and is still underway. The materials tested were SA508 Gr.1a low alloy steels, 316LN stainless steels, cast stainless steels, and an Alloy 690 and 52M weld. Through tests and subsequent analysis, the mechanisms of reduced low cycle fatigue life have been investigated for those alloys. In addition, the effects of temperature, dissolved oxygen level, and dissolved hydrogen level on low cycle fatigue behaviors have been investigated. In this paper, the test results and key analysis results are briefly summarized. Finally, an on-going test program for hot-bending of 347 stainless steel is introduced.

Characterization of nano structured metallic materials

International Nuclear Information System (INIS)

Marin A, M.; Gutierrez W, C.; Cruz C, R.; Angeles C, C.

1997-01-01

Nowadays the search of new materials with specific optical properties has carried out to realize a series of experiments through the polymer synthesis [(C 3 N 3 ) 2 (NH) 3 ] n doped with gold metallic nanoparticles. The thermal stability of a polymer is due to the presence of tyazine rings contained in the structure. The samples were characterized by High Resolution Transmission Electron Microscopy, X-ray diffraction by the Powder method, Ft-infrared and its thermal properties by Differential Scanning Calorimetry (DSC) and Thermogravimetry (TGA). One of the purposes of this work is to obtain nano structured materials over a polymeric matrix. (Author)

Rocksalt nitride metal/semiconductor superlattices: A new class of artificially structured materials

Science.gov (United States)

Saha, Bivas; Shakouri, Ali; Sands, Timothy D.

2018-06-01

Artificially structured materials in the form of superlattice heterostructures enable the search for exotic new physics and novel device functionalities, and serve as tools to push the fundamentals of scientific and engineering knowledge. Semiconductor heterostructures are the most celebrated and widely studied artificially structured materials, having led to the development of quantum well lasers, quantum cascade lasers, measurements of the fractional quantum Hall effect, and numerous other scientific concepts and practical device technologies. However, combining metals with semiconductors at the atomic scale to develop metal/semiconductor superlattices and heterostructures has remained a profoundly difficult scientific and engineering challenge. Though the potential applications of metal/semiconductor heterostructures could range from energy conversion to photonic computing to high-temperature electronics, materials challenges primarily had severely limited progress in this pursuit until very recently. In this article, we detail the progress that has taken place over the last decade to overcome the materials engineering challenges to grow high quality epitaxial, nominally single crystalline metal/semiconductor superlattices based on transition metal nitrides (TMN). The epitaxial rocksalt TiN/(Al,Sc)N metamaterials are the first pseudomorphic metal/semiconductor superlattices to the best of our knowledge, and their physical properties promise a new era in superlattice physics and device engineering.

Wear Resistance of 3D Printing Resin Material Opposing Zirconia and Metal Antagonists

Directory of Open Access Journals (Sweden)

Ji-Man Park

2018-06-01

Full Text Available 3D printing offers many advantages in dental prosthesis manufacturing. This study evaluated the wear resistance of 3D printing resin material compared with milling and conventional resin materials. Sixty substrate specimens were prepared with three types of resin materials: 3D printed resin, milled resin, and self-cured resin. The 3D printed specimens were printed at a build angle of 0° and 100 μm layer thickness by digital light processing 3D printing. Two kinds of abraders were made of zirconia and CoCr alloy. The specimens were loaded at 5 kg for 30,000 chewing cycles with vertical and horizontal movements under thermocycling condition. The 3D printed resin did not show significant difference in the maximal depth loss or the volume loss of wear compared to the milled and the self-cured resins. No significant difference was revealed depending on the abraders in the maximal depth loss or the volume loss of wear. In SEM views, the 3D printed resin showed cracks and separation of inter-layer bonds when opposing the metal abrader. The results suggest that the 3D printing using resin materials provides adequate wear resistance for dental use.

Oxygen production by molten alkali metal salts using multiple absorption-desorption cycles

Science.gov (United States)

Cassano, Anthony A.

1985-01-01

A continuous chemical air separation is performed wherein oxygen is recovered with a molten alkali metal salt oxygen acceptor in a series of absorption zones which are connected to a plurality of desorption zones operated in separate parallel cycles with the absorption zones. A greater recovery of high pressure oxygen is achieved at reduced power requirements and capital costs.

Design, Synthesis and Characterization of Functional Metal-Organic Framework Materials

KAUST Repository

Alamer, Badriah

2015-01-01

are known as Metal Organic Framework (MOFs). This exceptional new family of porous materials is fabricated by linkage of metal ions or clusters and organic linkers via strong bonds. MOFs have been awarded with remarkable interest and widely studied due

System for Prevention, Detection and Response to Radioactive Materials in Scrap Metal in Ukraine

Energy Technology Data Exchange (ETDEWEB)

Makarovska, O., E-mail: makarovska@hq.snrc.gov.ua [State Nuclear Regulatory Committee of Ukraine, Kiev (Ukraine)

2011-07-15

The State control system to prevent, detect and respond to cases of radioactive material in scrap metal is functioning in Ukraine. The system includes regulations for the safe and secure management of metal scrap and administrative and technical measures to prevent, detect and respond to cases of radioactive material in scrap metal. The key elements of prevention are the system of licensing and supervision in the sphere of radioactive material use and the State system for inventory, registration and control of radiation sources. Metal scrap management is licensed by the Ministry of Industrial Policy and one of the licence conditions is radiation control of the scrap metal. State supervision of the operations with metal scrap is provided by Ministry of Health and Ministry of Environmental Protection according to the regulation 'State sanitary-ecological standard for metal scrap management'. Specific standards exist for the export of metal scrap. Export consignments are followed by a certificate that proves the radiological safety of the metal. Ukrainian metallurgical plants provide an input radiation control of metal scrap and an output control of the produced metal. Thus, there exists a five barrier system of metal scrap control: border control; exclusion zone perimeter control; metal scrap dealers control; metallurgical plants (input control and output control of produced metal); and export consignments radiological certification. To regain control over orphan sources (including occasional radioactive material in the scrap metal) the 'procedure for interaction of executive authorities and involved legal entities in case of revealing of radiation sources in no legal use' was approved by a Resolution of the Cabinet of Ministers of Ukraine. The investigation of each case with feedback, information of involved bodies, safe and secure storage of restored radioactive material are provided according to this procedure. (author)

Compatibility tests between molten salts and metal materials (2)

International Nuclear Information System (INIS)

Shiina, Yasuaki

2003-08-01

Latent heat storage technology using molten salts can reduce temperature fluctuations of heat transfer fluid by latent heat for middle and high temperature regions. This enables us to operate several heat utilization systems in cascade connected to High Temperature Gas Cooled Reactors (HTGRs) from high to low temperature range by setting the latent heat storage system after a heat utilization system to reduce thermal load after the heat utilization systems. This latent heat technology is expected to be used for effective use of heat such as equalization of electric load between night and daytime. In the application of the latent heat technology, compatibility between molten salts and metal materials is very important because molten salts are corrosive, and heat transfer pipes and vessels will contact with the molten salts. It will be necessary to prevail the latent heat storage technique that normal metal materials can be used for the pipes and vessels. However, a few studies have been reported of compatibility between molten salts and metals in middle and high temperature ranges. In this study, four molten salts, range of the melting temperature from 490degC to 800degC, are selected and five metals, high temperature and corrosion resistance steels of Alloy600, HastelloyB2, HastelloyC276, SUS310S and pure Nickel are selected for the test with the consideration of metal composition. Test was performed in an electric furnace by setting the molten salts and the metals in melting pots in an atmosphere of nitrogen. Results revealed excellent corrosion resistance of pure Nickel and comparatively low corrosion resistance of nickel base alloys such as Alloy600 and Hastelloys against Li 2 CO 3 . Corrosion resistance of SUS310S was about same as nickel based alloys. Therefore, if some amount of corrosion is permitted, SUS310S would be one of the candidate alloys for structure materials. These results will be used as reference data to select metals in latent heat technology

Development and application of basis database for materials life cycle assessment in china

Science.gov (United States)

Li, Xiaoqing; Gong, Xianzheng; Liu, Yu

2017-03-01

As the data intensive method, high quality environmental burden data is an important premise of carrying out materials life cycle assessment (MLCA), and the reliability of data directly influences the reliability of the assessment results and its application performance. Therefore, building Chinese MLCA database is the basic data needs and technical supports for carrying out and improving LCA practice. Firstly, some new progress on database which related to materials life cycle assessment research and development are introduced. Secondly, according to requirement of ISO 14040 series standards, the database framework and main datasets of the materials life cycle assessment are studied. Thirdly, MLCA data platform based on big data is developed. Finally, the future research works were proposed and discussed.

Liquid metal current collector applications and material compatibility

International Nuclear Information System (INIS)

Carr, S.L.; Stevens, H.O.

1978-01-01

The objective of this paper has been to summarize briefly the material considerations involved in the development of liquid metal current collectors for homopolar machinery applications. A significant amount of data in this regard has been obtained over the last several years by individual researchers for NaK exposure conditions. However, NaK material compatibility data over the entire time and temperature range of interest is highly desirable. At DTNSRDC, a 300 kW superconducting homopolar motor and generator are under test, both utilizing free surface tongue-and-groove current collectors with NaK as the working fluid. In addition to demonstrating the feasibility of other aspects of machine design, the intention is to use these machines as vehicles for testing of the several liquid metal current collector concepts which are considered worthwhile candidates for incorporation in future full-scale machines. It is likely that the optimal collector approach for a large low speed motor may be quite different from that for a smaller high speed generator, possibly involving the use of different liquid metals

Metal spectra as indicators of development

Science.gov (United States)

Graedel, T. E.; Cao, J.

2010-01-01

We have assembled extensive information on the cycles of seven industrial metals in 49 countries, territories, or groups of countries, drawn from a database of some 200,000 material flows, and have devised analytical approaches to treat the suite of metals as composing an approach to a national “materials metabolism.” We demonstrate that in some of the more developed countries, per capita metal use is more than 10 times the global average. Additionally, countries that use more than the per capita world average of any metal do so for all metals, and vice versa, and countries that are above global average rates of use are very likely to be above global average rates at all stages of metal life cycles from fabrication onward. We show that all countries are strongly dependent on international trade to supply the spectrum of nonrenewable resources that modern technology requires, regardless of their level of development. We also find that the rate of use of the spectrum of metals stock is highly correlated to per capita gross domestic product, as well as to the Human Development Index and the Global Competitiveness Innovation Index. The implication is that as wealth and technology increase in developing countries, strong demand will be created not for a few key resources, but across the entire spectrum of the industrial metals. Long-term metal demand can be estimated given gross domestic product projections; the results suggest overall metal flow into use in 2050 of 5–10 times today’s level should supplies permit. PMID:21098309

Investigation of Liquid Metal Embrittlement of Materials for use in Fusion Reactors

Science.gov (United States)

Kennedy, Daniel; Jaworski, Michael

2014-10-01

Liquid metals can provide a continually replenished material for the first wall and extraction blankets of fusion reactors. However, research has shown that solid metal surfaces will experience embrittlement when exposed to liquid metals under stress. Therefore, it is important to understand the changes in structural strength of the solid metal materials and test different surface treatments that can limit embrittlement. Research was conducted to design and build an apparatus for exposing solid metal samples to liquid metal under high stress and temperature. The apparatus design, results of tensile testing, and surface imaging of fractured samples will be presented. This work was supported in part by the U.S. Department of Energy, Office of Science, Office of Workforce Development for Teachers and Scientists (WDTS) under the Science Undergraduate Laboratory Internships Program (SULI).

Metals and Alloys Material Stabilization Process Plan

Energy Technology Data Exchange (ETDEWEB)

RISENMAY, H.R.; BURK, R.A.

2000-05-18

This Plan outlines the process for brushing metal and alloys in accordance with the path forward discussed in the Integrated Project Management Plan for the Plutonium Finishing Plant Stabilization and Deactivation Project, HNF-3617, and requirements set forth in the Project Management Plan for Materials Stabilization, HNF-3605. This plan provides the basis for selection of the location to process, the processes involved, equipment to be used, and the characterization of the contents of the can. The scope of the process is from retrieval of metals and alloys from storage to transfer back to storage in a repackaged configuration.

Metals and Alloys Material Stabilization Process Plan

International Nuclear Information System (INIS)

RISENMAY, H.R.; BURK, R.A.

2000-01-01

This Plan outlines the process for brushing metal and alloys in accordance with the path forward discussed in the Integrated Project Management Plan for the Plutonium Finishing Plant Stabilization and Deactivation Project, HNF-3617, and requirements set forth in the Project Management Plan for Materials Stabilization, HNF-3605. This plan provides the basis for selection of the location to process, the processes involved, equipment to be used, and the characterization of the contents of the can. The scope of the process is from retrieval of metals and alloys from storage to transfer back to storage in a repackaged configuration

Inorganic nanostructured materials for high performance electrochemical supercapacitors

Science.gov (United States)

Liu, Sheng; Sun, Shouheng; You, Xiao-Zeng

2014-01-01

Electrochemical supercapacitors (ES) are a well-known energy storage system that has high power density, long life-cycle and fast charge-discharge kinetics. Nanostructured materials are a new generation of electrode materials with large surface area and short transport/diffusion path for ions and electrons to achieve high specific capacitance in ES. This mini review highlights recent developments of inorganic nanostructure materials, including carbon nanomaterials, metal oxide nanoparticles, and metal oxide nanowires/nanotubes, for high performance ES applications.

Oxygen production by molten alkali metal salts using multiple absorption-desorption cycles

Science.gov (United States)

Cassano, A.A.

1985-07-02

A continuous chemical air separation is performed wherein oxygen is recovered with a molten alkali metal salt oxygen acceptor in a series of absorption zones which are connected to a plurality of desorption zones operated in separate parallel cycles with the absorption zones. A greater recovery of high pressure oxygen is achieved at reduced power requirements and capital costs. 3 figs.

Machinability studies of infrared window materials and metals

International Nuclear Information System (INIS)

Arnold, J.B.; Morris, T.O.; Sladky, R.E.; Steger, P.J.

1976-01-01

Diamond machining of materials for optical applications is becoming an important fabrication process. Development work in material-removal technology to better understand the mechanics of the diamond-turning process, its limitations, and applications is described. The technique is presently limited to a select group of metals, most of which are of a face-center-cubic crystal structure. Machinability studies were done which were designed to better understand diamond compatibility and thus expand the range of applicable materials. Nonconventional methods such as ultrasonic tool stimulation were investigated. Work done to determine the machinability of infrared window materials indicates that this is a viable fabrication technique for many materials, although additional effort is needed to optimize the process for particular materials

Metals and metalloids treatment in contaminated neutral effluents using modified materials.

Science.gov (United States)

Calugaru, Iuliana Laura; Neculita, Carmen Mihaela; Genty, Thomas; Zagury, Gérald J

2018-04-15

Circumneutral surface water and groundwater can contain hazardous concentrations of metals and metalloids that can threaten organisms in surrounding ecosystems. Extensive research has been conducted over the past two decades to prevent, limit, and treat water pollution. Among the currently available treatment options is the use of natural and residual materials, which is generally regarded as effective and inexpensive. The modification of such materials enhances the removal capacity of metals and metalloids, as well as the physical and chemical stability of the materials and resulting sludge (after treatment). This paper reviews several modified materials that have produced and evaluated in the past twenty years to treat various contaminants in water under specific conditions. Important factors on performance improvement following the modifications are emphasized. Sorption capacity and kinetics, and element removal mechanisms are also discussed. Element recovery, material regeneration, water reuse, evaluation of treatment efficiency for real effluents are also considered, as well as the applicability of these materials in both active and passive treatment systems. Modified natural and residual materials are a promising option for the treatment of metals and metalloids in circumneutral contaminated waters. However, further research is necessary to evaluate their field-scale performance and to properly assess treatment costs. Copyright © 2018 Elsevier Ltd. All rights reserved.

A Micro-Test Structure for the Thermal Expansion Coefficient of Metal Materials

Directory of Open Access Journals (Sweden)

Qingying Ren

2017-02-01

Full Text Available An innovative micro-test structure for detecting the thermal expansion coefficient (TEC of metal materials is presented in this work. Throughout this method, a whole temperature sensing moveable structures are supported by four groups of cascaded chevrons beams and packed together. Thermal expansion of the metal material causes the deflection of the cascaded chevrons, which leads to the capacitance variation. By detecting the capacitance value at different temperatures, the TEC value of the metal materials can be calculated. A finite element model has been established to verify the relationship between the TEC of the material and the displacement of the structure on horizontal and vertical directions, thus a function of temperature for different values of TEC can be deduced. In order to verify the analytical model, a suspended-capacitive micro-test structure has been fabricated by MetalMUMPs process and tested in a climate chamber. Test results show that in the temperature range from 30 °C to 80 °C, the TEC of the test material is 13.4 × 10−6 °C−1 with a maximum relative error of 0.8% compared with the given curve of relationship between displacement and temperature.

Metallization for Yb14MnSb11-Based Thermoelectric Materials

Science.gov (United States)

Firdosy, Samad; Li, Billy Chun-Yip; Ravi, Vilupanur; Sakamoto, Jeffrey; Caillat, Thierry; Ewell, Richard C.; Brandon, Erik J.

2011-01-01

Thermoelectric materials provide a means for converting heat into electrical power using a fully solid-state device. Power-generating devices (which include individual couples as well as multicouple modules) require the use of ntype and p-type thermoelectric materials, typically comprising highly doped narrow band-gap semiconductors which are connected to a heat collector and electrodes. To achieve greater device efficiency and greater specific power will require using new thermoelectric materials, in more complex combinations. One such material is the p-type compound semiconductor Yb14MnSb11 (YMS), which has been demonstrated to have one of the highest ZT values at 1,000 C, the desired operational temperature of many space-based radioisotope thermoelectric generators (RTGs). Despite the favorable attributes of the bulk YMS material, it must ultimately be incorporated into a power-generating device using a suitable joining technology. Typically, processes such as diffusion bonding and/or brazing are used to join thermoelectric materials to the heat collector and electrodes, with the goal of providing a stable, ohmic contact with high thermal conductivity at the required operating temperature. Since YMS is an inorganic compound featuring chemical bonds with a mixture of covalent and ionic character, simple metallurgical diffusion bonding is difficult to implement. Furthermore, the Sb within YMS readily reacts with most metals to form antimonide compounds with a wide range of stoichiometries. Although choosing metals that react to form high-melting-point antimonides could be employed to form a stable reaction bond, it is difficult to limit the reactivity of Sb in YMS such that the electrode is not completely consumed at an operating temperature of 1,000 C. Previous attempts to form suitable metallization layers resulted in poor bonding, complete consumption of the metallization layer or fracture within the YMS thermoelement (or leg).

Charge transfer and redistribution at interfaces between metals and 2D materials

NARCIS (Netherlands)

Bokdam, Menno

2013-01-01

Large potential steps are observed at the interfaces between metals and novel 2D materials. They can lower the work function by more than 1 eV, even when the two parts are only weakly interacting. In this thesis the transfer and redistribution of electrons in metal|2D material heterostructures are

Non-Destructive Metallic Materials Testing—Recent Research and Future Perspectives

Directory of Open Access Journals (Sweden)

João Manuel R. S. Tavares

2017-10-01

Full Text Available Non-destructive testing (NDT has become extremely important formicrostructural characterization, mainly by allowing the assessment of metallic material properties in an effective and reasonable manner, in addition to maintaining the integrity of the evaluated metallic samples and applicability in service in many cases [...

Low cycle fatigue of irradiated LMFBR materials

International Nuclear Information System (INIS)

Blackburn, L.D.

1976-01-01

A review of low cycle fatigue data on irradiated LMFBR materials was conducted and extensive graphical representations of available data are presented. Representative postirradiation tensile properties of annealed 304 and 316 SS are selected and employed in several predictive methods to estimate irradiated material fatigue curves. Experimental fatigue data confirm the use of predictive methods for establishing conservative design curves over the range of service conditions relevant to such CRBRP components as core former, fixed radial shielding, core barrel, lower inlet module and upper internals structures. New experimental data on fatigue curves and creep-fatigue interaction in irradiated 20 percent cold worked (CW) 316 SS and Alloy 718 would support the design of removable radial shielding and upper internals in CRBRP. New experimental information on notched fatigue behavior and cyclic stress-strain curves of all these materials in the irradiated condition could provide significant design data

Economics of radioactive material transportation in the light-water reactor nuclear fuel cycle

International Nuclear Information System (INIS)

Dupree, S.A.; O'Malley, L.C.

1980-10-01

This report presents estimates of certain transportation costs, in 1979 dollars, associated with Light-Water Reactor (LWR) once-through and recycle fuel cycles. Shipment of fuel, high-level waste and low-level waste was considered. Costs were estimated for existing or planned transportation systems and for recommended alternate systems, based on the assumption of mature fuel cycles. The annual radioactive material transportation costs required to support a nominal 1000-MW(e) LWR in a once-through cycle in which spent fuel is shipped to terminal storage or disposal were found to be approx. $490,000. Analogous costs for an average reactor operating in a fuel cycle with uranium and plutonim recycle were determined to be approx. $770,000. These results assume that certain recommended design changes will occur in radioactive material shipping systems as a mature fuel cycle evolves

Feasibility investigation of non-metallic and light weight metallic materials for light weight compressor pistons

NARCIS (Netherlands)

Wentzel, C.M.; Bergsma, O.K.; Eijk, A.

2014-01-01

Steel and aluminium have been the traditional materials of choice for pistons. In order to reduce moving mass-related vibrational problems, a feasibility assessment is made of the application of other materials in a project for the research group of the EFRC. In particular, polymer and metal matrix

All heavy metals closed-cycle analysis on water-cooled reactors of uranium and thorium fuel cycle systems

International Nuclear Information System (INIS)

Permana, Sidik; Sekimoto, Hiroshi; Waris, Abdul; Takaki, Naoyuki

2009-01-01

Uranium and Thorium fuels as the basis fuel of nuclear energy utilization has been used for several reactor types which produce trans-uranium or trans-thorium as 'by product' nuclear reaction with higher mass number and the remaining uranium and thorium fuels. The utilization of recycled spent fuel as world wide concerns are spent fuel of uranium and plutonium and in some cases using recycled minor actinide (MA). Those fuel schemes are used for improving an optimum nuclear fuel utilization as well to reduce the radioactive waste from spent fuels. A closed-cycle analysis of all heavy metals on water-cooled cases for both uranium and thorium fuel cycles has been investigated to evaluate the criticality condition, breeding performances, uranium or thorium utilization capability and void reactivity condition. Water-cooled reactor is used for the basic design study including light water and heavy water-cooled as an established technology as well as commercialized nuclear technologies. A developed coupling code of equilibrium fuel cycle burnup code and cell calculation of SRAC code are used for optimization analysis with JENDL 3.3 as nuclear data library. An equilibrium burnup calculation is adopted for estimating an equilibrium state condition of nuclide composition and cell calculation is performed for calculating microscopic neutron cross-sections and fluxes in relation to the effect of different fuel compositions, different fuel pin types and moderation ratios. The sensitivity analysis such as criticality, breeding performance, and void reactivity are strongly depends on moderation ratio and each fuel case has its trend as a function of moderation ratio. Heavy water coolant shows better breeding performance compared with light water coolant, however, it obtains less negative or more positive void reactivity. Equilibrium nuclide compositions are also evaluated to show the production of main nuclides and also to analyze the isotopic composition pattern especially

Statistical treatment of hazards result from radioactive material in metal scrap

International Nuclear Information System (INIS)

Salem, E.F.; Rashad, S.M.

2013-01-01

Radioactive sources have a wide range of uses in medicine and industry. Radioactive materials entering the public domain in an uncontrolled manner may creating a serious risk of radiation exposure for workers and the public as well as excessive costs for plant decontamination and waste of product to be borne by the metal industry. This paper describes the major accidents that had happened in the last decades due to radioactive material in metal scrap, provides assessment of associated hazards and lessons learned. This will help Regulatory Authority to introduce measures capable to avoid the recurrence of similar events. The study highlights the situation for metal scrap incidents in Egypt.

A life cycle assessment of destruction of ammunition

International Nuclear Information System (INIS)

Alverbro, K.; Bjoerklund, A.; Finnveden, G.; Hochschorner, E.; Haegvall, J.

2009-01-01

The Swedish Armed Forces have large stocks of ammunition that were produced at a time when decommissioning was not considered. This ammunition will eventually become obsolete and must be destroyed, preferably with minimal impact on the environment and in a safe way for personnel. The aim of this paper is to make a comparison of the environmental impacts in a life cycle perspective of three different methods of decommissioning/destruction of ammunition, and to identify the environmental advantages and disadvantages of each of these destruction methods: open detonation; static kiln incineration with air pollution control combined with metal recycling, and a combination of incineration with air pollution control, open burning, recovery of some energetic material and metal recycling. Data used are for the specific processes and from established LCA databases. Recycling the materials in the ammunition and minimising the spread of airborne pollutants during incineration were found to be the most important factors affecting the life cycle environmental performance of the compared destruction methods. Open detonation with or without metal recycling proved to be the overall worst alternative from a life cycle perspective. The results for the static kiln and combination treatment indicate that the kind of ammunition and location of the destruction plant might determine the choice of method, since the environmental impacts from these methods are of little difference in the case of this specific grenade. Different methods for destruction of ammunition have previously been discussed from a risk and safety perspective. This is however to our knowledge the first study looking specifically on environmentally aspect in a life cycle perspective.

Experimental investigation of solidification in metal foam enhanced phase change material

Science.gov (United States)

Beyne, W.; Bağci, O.; Huisseune, H.; Canière, H.; Danneels, J.; Daenens, D.; De Paepe, M.

2017-10-01

A major challenge for the use of phase change materials (PCMs) in thermal energy storage (TES) is overcoming the low thermal conductivity of PCM’s. The low conductivity gives rise to limited power during charging and discharging TES. Impregnating metal foam with PCM, however, has been found to enhance the heat transfer. On the other hand, the effect of foam parameters such as porosity, pore size and material type has remained unclear. In this paper, the effect of these foam parameters on the solidification time is investigated. Different samples of PCM-impregnated metal foam were experimentally tested and compared to one without metal foam. The samples varied with respect to choice of material, porosity and pore size. They were placed in a rectangular cavity and cooled from one side using a coolant flowing through a cold plate. The other sides of the rectangular cavity were Polymethyl Methacrylate (PM) walls exposed to ambient. The temperature on the exterior walls of the cavity was monitored as well as the coolant flow rate and its temperature. The metal foam inserts reduced the solidification times by at least 25 %. However, the difference between the best performing and worst performing metal foam is about 28 %. This shows a large potential for future research.

Towards Flexible Transparent Electrodes Based on Carbon and Metallic Materials

Directory of Open Access Journals (Sweden)

Minghui Luo

2017-01-01

Full Text Available Flexible transparent electrodes (FTEs with high stability and scalability are in high demand for the extremely widespread applications in flexible optoelectronic devices. Traditionally, thin films of indium thin oxide (ITO served the role of FTEs, but film brittleness and scarcity of materials limit its further application. This review provides a summary of recent advances in emerging transparent electrodes and related flexible devices (e.g., touch panels, organic light-emitting diodes, sensors, supercapacitors, and solar cells. Mainly focusing on the FTEs based on carbon nanomaterials (e.g., carbon nanotubes and graphene and metal materials (e.g., metal grid and metal nanowires, we discuss the fabrication techniques, the performance improvement, and the representative applications of these highly transparent and flexible electrodes. Finally, the challenges and prospects of flexible transparent electrodes will be summarized.

Metal Oxide Nanostructured Materials for Optical and Energy Applications

OpenAIRE

Moore, Michael Christopher

2013-01-01

With a rapidly growing population, dwindling resources, and increasing environmental pressures, the need for sustainable technological solutions becomes more urgent. Metal oxides make up much of the earth's crust and are typically inexpensive materials, but poor electrical and optical properties prevent them from being useful for most semiconductor applications. Recent breakthroughs in chemistry and materials science allow for the growth of high-quality materials with nanometer-scale features...

Persistent cyclestability of carbon coated Zn–Sn metal oxide/carbon microspheres as highly reversible anode material for lithium-ion batteries

International Nuclear Information System (INIS)

Fang, Guoqing; Kaneko, Shingo; Liu, Weiwei; Xia, Bingbo; Sun, Hongdan; Zhang, Ruixue; Zheng, Junwei; Li, Decheng

2013-01-01

Development of high-capacity anode materials equipped with strong cyclestability is a great challenge for use as practical electrode for high-performance lithium-ion rechargeable battery. In this study, we synthesized a carbon coated Zn–Sn metal nanocomposite oxide and carbon spheres (ZTO@C/CSs) via a simple glucose hydrothermal reaction and subsequent carbonization approach. The carbon coated ZTO/carbon microspheres composite maintained a reversible capacity of 680 mAh g −1 after 345 cycles at a current density of 100 mA g −1 , and furthermore the cell based on the composite exhibited an excellent rate capability of 470 mAh g −1 even when the cell was cycled at 2000 mA g –1 . The thick carbon layer formed on the ZTO nanoparticles and carbon spheres effectively buffered the volumetric change of the particles, which thus prolonged the cycling performance of the electrodes

Manganese pyridinedicarboxylates: New anode materials for lithium-ion batteries with good cycling performance

International Nuclear Information System (INIS)

Fei, Hailong; Li, Zhiwei; Liu, Xin

2015-01-01

Highlights: • Manganese 2,3-pyridinedicarboxylate and 2,5-pyridinedicarboxylate. • Firstly tested as anode materials. • High capacity and good cycle stability. - Abstract: It is significant to discover new environmental friendly, sustainable and renewable electrode materials for lithium-ion batteries. Manganese dicarboxylate [Mn 2 (pdc) 2 (H 2 O) 3 ] n ⋅2nH 2 O (pdc = pyridine-2,3-dicarboxylate) is firstly found to be a high-energy anode material for lithium-ion batteries. It shows a high discharge capacity of 573.7 mA h g −1 for the second cycle between a 0.05 and 3.0 V voltage limit at a discharge current density of 500 mA g −1 . The reversible capacity of 457.2 mA h g −1 is remained after 100 cycles with a capacity retention being 79.6%. In addition, it is found that Mn 2,5-pyridinedicarboxyle was also stable anode materials with high capacity

Processing and properties of silver-metal oxide electrical contact materials

Directory of Open Access Journals (Sweden)

Nadežda M. Talijan

2012-12-01

Full Text Available The presented study gives a brief overview of the experimental results of investigations of different production technologies of silver-metal oxide electrical contact materials in relation: processing method - properties. The two most common routes of production, i.e. internal oxidation/ingot metallurgy and powder metallurgy are demonstrated on the example of Ag-CdO and Ag-ZnO materials. For illustration of alternative processing routes that provide higher dispersion of metal-oxide particles in silver matrix more environmentally friendly Ag-SnO2 contact materials are used. Processing of electrical contact materials by mechanical mixing of starting powders in high energy ball mill is presented. The obtained experimental results of application of different methods of introduction of SnO2 nanoparticles in the silver matrix such as conventional powder metallurgy mixing and template method are given and discussed in terms of their influence on microstructure and physical properties (density, hardness and electrical conductivity of the prepared Ag-SnO2 electrical contact materials.

Fluorine uptake into human enamel around fluoride-containing dental materials during cariogenic pH cycling

Energy Technology Data Exchange (ETDEWEB)

Komatsu, H. [Graduate School of Dental Medicine, Hokkaido University, Kita-13, Nishi-7, Kita-ku, Sapporo 060-8586 (Japan)], E-mail: kom@den.hokudai.ac.jp; Yamamoto, H. [Graduate School of Dentistry, Osaka University, 1-8 Yamada-Oka, Suita 565-0871 (Japan); Nomachi, M. [Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka 560-0043 (Japan); Yasuda, K. [The Wakasa wan Energy Research Center, 64-52-1 Hase, Tsuruga 914-0192 (Japan); Matsuda, Y.; Kinugawa, M.; Kijimura, T.; Sano, H. [Graduate School of Dental Medicine, Hokkaido University, Kita-13, Nishi-7, Kita-ku, Sapporo 060-8586 (Japan); Satou, T.; Oikawa, S.; Kamiya, T. [Advanced Radiation Technology, TARRI, JAEA, 1233 Watanuki-machi, Takasaki 370-1292 (Japan)

2009-06-15

Using PIGE (Proton Induced Gamma Emission) technique at TARRI (Takasaki Advanced Radiation Research Institute), Japan, we measured fluorine (F) uptake into the tooth enamel around two fluoride-containing materials during caries progression using pH cycling. Class V cavities in extracted human teeth were drilled and filled with fluoride-containing materials (i.e. 'Fuji IX' (FN) and 'UniFil flow with MEGA bond' (UF)) and a non-fluoride-containing material (i.e. 'SOLARE with MEGA bond' (SO)). Three 120 {mu}m longitudinal sections including the filling material were obtained from each tooth. In order to simulate daily acid attack occurring in the oral cavity, the pH cycling (pH 6.8-4.5) was carried out for 1, 3 and 5 weeks, separately. After pH cycling, the caries progression in all specimens was observed using transverse microradiography (TMR). The F and calcium distributions of the specimens were evaluated using PIGE and PIXE techniques. The F distribution of the specimens clearly showed the F uptake from FN into enamel adjacent to the filling material, while the F uptakes from UF and SO were not detected. For UF, the MEGA bond (non-fluoride-containing) between the tooth and UniFil flow interfered with the F absorption into the tooth. For FN, the amount of F uptake into the subsurface enamel increased during pH cycling. The amount of F uptake in 5-week pH cycling had significantly higher value compared to those in 1- and 3-week pH cycling. For UF and SO, there were no significant differences between the different durations of pH cycling. Among fluoride-containing materials, there were some differences in the F uptake with increased pH cycling, which could possibly lead to obtaining difference in clinical performance. The data obtained using PIGE and PIXE techniques were useful in understanding the benefit of fluorine by means of fluoride-containing material for preventing caries.

Fluorine uptake into human enamel around fluoride-containing dental materials during cariogenic pH cycling

International Nuclear Information System (INIS)

Komatsu, H.; Yamamoto, H.; Nomachi, M.; Yasuda, K.; Matsuda, Y.; Kinugawa, M.; Kijimura, T.; Sano, H.; Satou, T.; Oikawa, S.; Kamiya, T.

2009-01-01

Using PIGE (Proton Induced Gamma Emission) technique at TARRI (Takasaki Advanced Radiation Research Institute), Japan, we measured fluorine (F) uptake into the tooth enamel around two fluoride-containing materials during caries progression using pH cycling. Class V cavities in extracted human teeth were drilled and filled with fluoride-containing materials (i.e. 'Fuji IX' (FN) and 'UniFil flow with MEGA bond' (UF)) and a non-fluoride-containing material (i.e. 'SOLARE with MEGA bond' (SO)). Three 120 μm longitudinal sections including the filling material were obtained from each tooth. In order to simulate daily acid attack occurring in the oral cavity, the pH cycling (pH 6.8-4.5) was carried out for 1, 3 and 5 weeks, separately. After pH cycling, the caries progression in all specimens was observed using transverse microradiography (TMR). The F and calcium distributions of the specimens were evaluated using PIGE and PIXE techniques. The F distribution of the specimens clearly showed the F uptake from FN into enamel adjacent to the filling material, while the F uptakes from UF and SO were not detected. For UF, the MEGA bond (non-fluoride-containing) between the tooth and UniFil flow interfered with the F absorption into the tooth. For FN, the amount of F uptake into the subsurface enamel increased during pH cycling. The amount of F uptake in 5-week pH cycling had significantly higher value compared to those in 1- and 3-week pH cycling. For UF and SO, there were no significant differences between the different durations of pH cycling. Among fluoride-containing materials, there were some differences in the F uptake with increased pH cycling, which could possibly lead to obtaining difference in clinical performance. The data obtained using PIGE and PIXE techniques were useful in understanding the benefit of fluorine by means of fluoride-containing material for preventing caries.

Life cycle assessment of sustainable raw material acquisition for functional magnetite bionanoparticle production.

Science.gov (United States)

Sadhukhan, Jhuma; Joshi, Nimisha; Shemfe, Mobolaji; Lloyd, Jonathan R

2017-09-01

Magnetite nanoparticles (MNPs) have several applications, including use in medical diagnostics, renewable energy production and waste remediation. However, the processes for MNP production from analytical-grade materials are resource intensive and can be environmentally damaging. This work for the first time examines the life cycle assessment (LCA) of four MNP production cases: (i) industrial MNP production system; (ii) a state-of-the-art MNP biosynthesis system; (iii) an optimal MNP biosynthesis system and (iv) an MNP biosynthesis system using raw materials sourced from wastewaters, in order to recommend a sustainable raw material acquisition pathway for MNP synthesis. The industrial production system was used as a benchmark to compare the LCA performances of the bio-based systems (cases ii-iv). A combination of appropriate life cycle impact assessment methods was employed to analyse environmental costs and benefits of the systems comprehensively. The LCA results revealed that the state-of-the-art MNP biosynthesis system, which utilises analytical grade ferric chloride and sodium hydroxide as raw materials, generated environmental costs rather than benefits compared to the industrial MNP production system. Nevertheless, decreases in environmental impacts by six-fold were achieved by reducing sodium hydroxide input from 11.28 to 1.55 in a mass ratio to MNPs and replacing ferric chloride with ferric sulphate (3.02 and 2.59, respectively, in a mass ratio to MNPs) in the optimal biosynthesis system. Thus, the potential adverse environmental impacts of MNP production via the biosynthesis system can be reduced by minimising sodium hydroxide and substituting ferric sulphate for ferric chloride. Moreover, considerable environmental benefits were exhibited in case (iv), where Fe(III) ions were sourced from metal-containing wastewaters and reduced to MNPs by electrons harvested from organic substrates. It was revealed that 14.4 kJ and 3.9 kJ of primary fossil resource

Investigation of Lithium Metal Hydride Materials for Mitigation of Deep Space Radiation

Science.gov (United States)

Rojdev, Kristina; Atwell, William

2016-01-01

Radiation exposure to crew, electronics, and non-metallic materials is one of many concerns with long-term, deep space travel. Mitigating this exposure is approached via a multi-faceted methodology focusing on multi-functional materials, vehicle configuration, and operational or mission constraints. In this set of research, we are focusing on new multi-functional materials that may have advantages over traditional shielding materials, such as polyethylene. Metal hydride materials are of particular interest for deep space radiation shielding due to their ability to store hydrogen, a low-Z material known to be an excellent radiation mitigator and a potential fuel source. We have previously investigated 41 different metal hydrides for their radiation mitigation potential. Of these metal hydrides, we found a set of lithium hydrides to be of particular interest due to their excellent shielding of galactic cosmic radiation. Given these results, we will continue our investigation of lithium hydrides by expanding our data set to include dose equivalent and to further understand why these materials outperformed polyethylene in a heavy ion environment. For this study, we used HZETRN 2010, a one-dimensional transport code developed by NASA Langley Research Center, to simulate radiation transport through the lithium hydrides. We focused on the 1977 solar minimum Galactic Cosmic Radiation environment and thicknesses of 1, 5, 10, 20, 30, 50, and 100 g/cm2 to stay consistent with our previous studies. The details of this work and the subsequent results will be discussed in this paper.

Material control and accountability in nuclear fuel cycle

International Nuclear Information System (INIS)

Rumyantsev, A.N.

2006-01-01

It is proposed to unify the complexes, used in the systems for control and accountability of nuclear materials, and to use the successful experience of developing these complexes. It is shown that the problem of control, accountability and physical protection may by achieved by using the developed complex Probabilistic expert-advising system, permitting to analyse the safety in nuclear fuel cycles [ru

Metal nanoparticles in DBS card materials modification

Science.gov (United States)

Metelkin, A.; Frolov, G.; Kuznetsov, D.; Kolesnikov, E.; Chuprunov, K.; Kondakov, S.; Osipov, A.; Samsonova, J.

2015-11-01

In the recent years the method of collecting and storing Dried Blood Spots (DBS) on special cellulose membrane (paper) has gained wide popularity. But possible damage of biosamples caused by microorganisms in case of their incomplete drying is a disadvantage of the method. It can be overcome by treating sample-collection membranes with colloidal solutions of metal nanoparticles, having antibacterial effect. The team studied antibacterial properties of nonwoven material samples with various coatings (alcohol sols of copper, aluminium, iron, titanium, silver and vanadium nanoparticles). Colloidal solutions of nanoparticles were obtained by means of electroerosion method with further low-temperature plasma condensation. Antibacterial activity of fiberglass and cellulose membrane samples with nanoparticle coatings was studied using B. cereus and plaque bacteria cultures. It was revealed that nanostructured coatings can suppress bacterial activity; in addition they can diffuse from the membrane surface into medium which leads to widening the areas of inhibiting testing cultures’ growth. Thus, membrane materials treatment with alcohol-sols of metal nanoparticles can be seen as promising for conferring antibacterial properties to DBS carriers.

Metal nanoparticles in DBS card materials modification

International Nuclear Information System (INIS)

Metelkin, A; Frolov, G; Kuznetsov, D; Kolesnikov, E; Chuprunov, K; Kondakov, S; Osipov, A; Samsonova, J

2015-01-01

In the recent years the method of collecting and storing Dried Blood Spots (DBS) on special cellulose membrane (paper) has gained wide popularity. But possible damage of biosamples caused by microorganisms in case of their incomplete drying is a disadvantage of the method. It can be overcome by treating sample-collection membranes with colloidal solutions of metal nanoparticles, having antibacterial effect. The team studied antibacterial properties of nonwoven material samples with various coatings (alcohol sols of copper, aluminium, iron, titanium, silver and vanadium nanoparticles). Colloidal solutions of nanoparticles were obtained by means of electroerosion method with further low-temperature plasma condensation. Antibacterial activity of fiberglass and cellulose membrane samples with nanoparticle coatings was studied using B. cereus and plaque bacteria cultures. It was revealed that nanostructured coatings can suppress bacterial activity; in addition they can diffuse from the membrane surface into medium which leads to widening the areas of inhibiting testing cultures’ growth. Thus, membrane materials treatment with alcohol-sols of metal nanoparticles can be seen as promising for conferring antibacterial properties to DBS carriers. (paper)

Mesomorphic glass nanocomposites made of metal alkanoates and nanoparticles as emerging nonlinear-optical materials

Science.gov (United States)

Garbovskiy, Y.; Klimusheva, G.; Mirnaya, T.

2016-09-01

Mesomorphic metal alkanoates is very promising yet overlooked class of nonlinear-optical materials. Metal alkanoates can exhibit a broad variety of condensed states of matter including solid crystals, plastic crystals, lyotropic and thermotropic ionic liquid crystals, liquids, mesomorphic glasses, and Langmuir-Blodgett films. Glass-forming properties of metal alkanoates combined with their use as nano-reactors and anisotropic host open up simple and efficient way to design various photonic nanomaterials. Despite very interesting physics, the experimental data on optical and nonlinearoptical properties of such materials are scarce. The goal of the present paper is to fill the gap by discussing recent advances in the field of photonic materials made of metal alkanoates, organic dyes, and nanoparticles. Optical and nonlinear-optical properties of the following materials are reviewed: (i) mesomorphic glass doped with organic dyes; (ii) smectic glass composed of cobalt alkanoates; (iii) semiconductor nanoparticles embedded in a glassy host; (iv) metal nanoparticles - glass (the cobalt octanoate) nanocomposites.

Measurement of fracture toughness of metallic materials produced by additive manufacturing

Science.gov (United States)

Quénard, O.; Dorival, O.; Guy, Ph.; Votié, A.; Brethome, K.

2018-04-01

This study focuses on the microstructure and mechanical properties of metallic materials produced by additive layer manufacturing (ALM), especially the laser beam melting process. The influence of the specimen orientation during the ALM process and that of two post-build thermal treatments were investigated. The identified metal powder is Ti-6Al-4V (titanium base). Metallographic analysis shows their effects on the microstructure of the metals. Mechanical experiments involving tensile tests as well as toughness tests were performed according to ASTM (American Society for Testing and Materials) norms. The results show that the main influence is that of the thermal treatments; however the manufacturing stacking direction may lead to some anisotropy in the mechanical properties.

Materials damaging and rupture - Volumes 1-2. General remarks, metallic materials. Non-metallic materials and biomaterials, assemblies and industrial problems

International Nuclear Information System (INIS)

Clavel, M.; Bompard, P.

2009-01-01

The rupture and damaging of materials and structures is almost always and unwanted events which may have catastrophic consequences. Even if the mechanical failure causes can often be analyzed using a thorough knowledge of materials behaviour, the forecasting and prevention of failures remain difficult. While the macroscopic mechanical behaviour is often the result of average effects at the structure or microstructure scale, the damage is very often the result of the combination of load peaks, of localization effects and of microstructure defects. This book, presented in two volumes, takes stock of the state-of-the-art of the knowledge gained in the understanding and modelling of rupture and damaging phenomena of materials and structure, mostly of metallic type. It gives an outline of the available knowledge for other classes of materials (ceramics, biomaterials, geo-materials..) and for different types of applications (aeronautics, nuclear industry). Finally, it examines the delicate problem, but very important in practice, of the behaviour of assemblies. Content: Vol.1 - physical mechanisms of materials damaging and rupture; rupture mechanics; cyclic plasticity and fatigue crack growth; fatigue crack propagation; environment-induced cracking; contacts and surfaces. Vol.2 - glasses and ceramics; natural environments: soils and rocks; mechanical behaviour of biological solid materials: the human bone; contribution of simulation to the understanding of rupture mechanisms; assemblies damaging and rupture; industrial cases (behaviour of PWR pressure vessel steels, and thermal and mechanical stresses in turbojet engines). (J.S.)

Damage and failure modeling of lotus-type porous material subjected to low-cycle fatigue

Directory of Open Access Journals (Sweden)

J. Kramberger

2016-01-01

Full Text Available The investigation of low-cycle fatigue behaviour of lotus-type porous material is presented in this paper. Porous materials exhibit some unique features which are useful for a number of various applications. This paper evaluates a numerical approach for determining of damage initiation and evolution of lotus-type porous material with computational simulations, where the considered computational models have different pore topology patterns. The low-cycle fatigue analysis was performed by using a damage evolution law. The damage state was calculated and updated based on the inelastic hysteresis energy for stabilized cycle. Degradation of the elastic stifness was modeled using scalar damage variable. In order to examine crack propagation path finite elements with severe damage were deleted and removed from the mesh during simulation. The direct cyclic analysis capability in Abaqus/Standard was used for low-cycle fatigue analysis to obtain the stabilized response of a model subjected to the periodic loading. The computational results show a qualitative understanding of pores topology influence on low-cycle fatigue under transversal loading conditions in relation to pore orientation.

A Difference in Using Atomic Layer Deposition or Physical Vapour Deposition TiN as Electrode Material in Metal-Insulator-Metal and Metal-Insulator-Silicon Capacitors

NARCIS (Netherlands)

Groenland, A.W.; Wolters, Robertus A.M.; Kovalgin, Alexeij Y.; Schmitz, Jurriaan

2011-01-01

In this work, metal-insulator-metal (MIM) and metal-insulator-silicon (MIS) capacitors are studied using titanium nitride (TiN) as the electrode material. The effect of structural defects on the electrical properties on MIS and MIM capacitors is studied for various electrode configurations. In the

Results from low cycle fatigue testing of 316L plate and weld material

International Nuclear Information System (INIS)

Kaellstroem, R.; Josefsson, B.; Haag, Y.

1993-01-01

Specimens for low cycle fatigue testing from the second heat of the CEC reference 316L plate and from Tungsten Inert Gas (TIG) weld material have been neutron irradiated near room temperature to a displacement dose of approximately 0.3 dpa. The low cycle fatigue testing of both irradiated and unirradiated specimens was performed at 75, 250 and 450 degrees C, and with strain ranges of 0.75, 1.0 and 1.5%. There is no clear effect of the irradiation on low cycle fatigue properties. For the weld material the endurance is shorter than for plate, and the dependences on temperature and strain range are not clear

Materials considerations for the coupling of thermochemical hydrogen cycles to tandem mirror reactors

International Nuclear Information System (INIS)

Krikorian, O.H.

1980-01-01

Candidate materials are discussed and initial choices made for the critical elements in a liquid Li-Na Cauldron Tandem Mirror blanket and the General Atomic Sulfur-Iodine Cycle for thermochemical hydrogen production. V and Ti alloys provide low neutron activation, good radiation damage resistance, and good chemical compatibility for the Cauldron design. Aluminide coated In-800H and siliconized SiC are materials choices for heat exchanger components in the thermochemical cycle interface

Liquid metal batteries - materials selection and fluid dynamics

Science.gov (United States)

Weier, T.; Bund, A.; El-Mofid, W.; Horstmann, G. M.; Lalau, C.-C.; Landgraf, S.; Nimtz, M.; Starace, M.; Stefani, F.; Weber, N.

2017-07-01

Liquid metal batteries are possible candidates for massive and economically feasible large-scale stationary storage and as such could be key components of future energy systems based mainly or exclusively on intermittent renewable electricity sources. The completely liquid interior of liquid metal batteries and the high current densities give rise to a multitude of fluid flow phenomena that will primarily influence the operation of future large cells, but might be important for today’s smaller cells as well. The paper at hand starts with a discussion of the relative merits of using molten salts or ionic liquids as electrolytes for liquid metal cells and touches the choice of electrode materials. This excursus into electrochemistry is followed by an overview of investigations on magnetohydrodynamic instabilities in liquid metal batteries, namely the Tayler instability and electromagnetically excited gravity waves. A section on electro-vortex flows complements the discussion of flow phenomena. Focus of the flow related investigations lies on the integrity of the electrolyte layer and related critical parameters.

Risk associated with the transport of radioactive materials in the fuel cycle

International Nuclear Information System (INIS)

Lange, F.; Mairs, J.; Niel, C.

1997-01-01

This paper sets out the regulatory framework within which nuclear fuel cycle materials are transported. It establishes the basic principles of those safety regulations and explains the graded approach to satisfying those requirements depending on the hazard of the radioactive contents. The paper outlines the minimum performance standards required by the Regulations. It covers the performance standards for Type C packages in a little more detail because these are new to the 1996 Edition of the IAEA's Regulations for the Safe Transport of Radioactive Material and are less well reported elsewhere at present. The paper then gives approximate data on the number of shipments of radioactive materials that service the nuclear fuel cycles in France, Germany and the UK. The quantities are expressed as average annual quantities per GW el installed capacity. There is also a short discussion of the general performance standards required of Type B packages in comparison with tests that have simulated specific accident conditions involving particular packages. There follows a discussion on the probability of packages experiencing accident conditions that are comparable with the tests that Type B packages are required to withstand. Finally there is a summary of the implementation of the Regulations for sea and air transport and a description of ongoing work that may have a bearing on the future development of mode related Regulations. Nuclear fuel cycle materials are transported in accordance with strict and internationally agreed safety regulations which are the result of a permanent and progressive process based on social concern and on the advancement of knowledge provided by research and development. Transport operations take place in the public domain and some become high profile events in the management of these materials, attracting a lot of public, political and media attention. The risks associated with the transport of radioactive materials are low and it is important

Proposed fuel cycle for the Integral Fast Reactor

International Nuclear Information System (INIS)

Burris, L.; Walters, L.C.

1985-01-01

One of the key features of ANL's Integral Fast Reactor (IFR) concept is a close-coupled fuel cycle. The proposed fuel cycle is similar to that demonstrated over the first five to six years of operation of EBR-II, when a fuel cycle facility adjacent to EBR-II was operated to reprocess and refabricate rapidly fuel discharged from the EBR-II. Locating the IFR and its fuel cycle facility on the same site makes the IFR a self-contained system. Because the reactor fuel and the uranium blanket are metals, pyrometallurgical processes (shortned to ''pyroprocesses'') have been chosen. The objectives of the IFR processes for the reactor fuel and blanket materials are to (1) recover fissionable materials in high yield; (2) remove fission products adequately from the reactor fuel, e.g., a decontamination factor of 10 to 100; and (3) upgrade the concentration of plutonium in uranium sufficiently to replenish the fissile-material content of the reactor fuel. After the fuel has been reconstituted, new fuel elements will be fabricated for recycle to the reactor

Sensitization behaviour of modified 316N and 316L stainless steel weld metals after complex annealing and stress relieving cycles

International Nuclear Information System (INIS)

Parvathavarthini, N.; Dayal, R.K.; Khatak, H.S.; Shankar, V.; Shanmugam, V.

2006-01-01

Sensitization behaviour of austenitic stainless steel weld metals prepared using indigenously developed modified 316N (C = 0.05%; N = 0.12%) and 316L (C = 0.02%; N = 0.07%) electrodes was studied. Detailed optical and scanning electron microscopic examination was carried out to understand the microstructural changes occurring in the weld metal during isothermal exposure at various temperatures ranging from 500 deg. C to 850 deg. C (773-1123 K). Based on these studies the mechanism of sensitization in the austenite-ferrite weld metal has been explained. Time-temperature-sensitization (TTS) diagrams were established using ASTM A262 Practice E test. From the TTS diagrams, critical cooling rate (CCR) above which there is no risk of sensitization was calculated for both materials. The heating/cooling rates to be followed for avoiding sensitization during heat treatment cycles consisting of solution-annealing and stress-relieving in fabrication of welded components of AISI 316LN stainless steel (SS) were estimated taking into account the soaking time and the number of times the component undergoes thermal excursions in the sensitization regime. The results were validated by performing controlled heating and cooling heat treatment trials on welded specimens

A life cycle framework to support materials selection for Ecodesign: A case study on biodegradable polymers

International Nuclear Information System (INIS)

Ribeiro, I.; Peças, P.; Henriques, E.

2013-01-01

Highlights: • Life cycle framework to support material selection in Ecodesign. • Early design stage estimates and sensitivity analyses based on process-based models. • Sensitivity analysis to product geometry, industrial context and EoL scenarios. • Cost and environmental performance comparison – BDP vs. fossil based polymers. • Best alternatives mapping integrating cost and environmental performances. - Abstract: Nowadays society compels designers to develop more sustainable products. Ecodesign directs product design towards the goal of reducing environmental impacts. Within Ecodesign, materials selection plays a major role on product cost and environmental performance throughout its life cycle. This paper proposes a comprehensive life cycle framework to support Ecodesign in material selection. Dealing with new materials and technologies in early design stages, process-based models are used to represent the whole life cycle and supply integrated data to assess material alternatives, considering cost and environmental dimensions. An integrated analysis is then proposed to support decision making by mapping the best alternative materials according to the importance given to upstream and downstream life phases and to the environmental impacts. The proposed framework is applied to compare the life cycle performance of injection moulded samples made of four commercial biodegradable polymers with different contents of Thermo Plasticized Starch and PolyLactic Acid and a common fossil based polymer, Polypropylene. Instead of labelling materials just as “green”, the need to fully capture all impacts in the whole life cycle was shown. The fossil based polymer is the best economic alternative, but polymers with higher content of Thermo Plasticized Starch have a better environmental performance. However, parts geometry and EoL scenarios play a major role on the life cycle performance of candidate materials. The selection decision is then supported by mapping

New Nuclear Materials Including Non Metallic Fuel Elements. Vol. I. Proceedings of the Conference on New Nuclear Materials Technology, Including Non Metallic Fuel Elements

International Nuclear Information System (INIS)

1963-01-01

One of the major aims of the International Atomic Energy Agency in furthering the peaceful uses of atomic energy is to encourage the development of economical nuclear power. Certainly, one of the more obvious methods of producing economical nuclear power is the development of economical fuels that can be used at high temperatures for long periods of time, and which have sufficient strength and integrity to operate under these conditions without permitting the release of fission products. In addition it is desirable that after irradiation these new fuels be economically reprocessed to reduce further the cost of the fuel cycle. As nuclear power becomes more and more competitive with conventional power the interest in new and more efficient higher-temperature fuels naturally increases rapidly. For these reasons, the Agency organized a Conference on New Nuclear Materials Technology, Including Non-Metallic Fuel Elements, which was held from 1 to 5 July 1963 at the International Hotel, Prague, with the assistance and co-operation of the Government of the Czechoslovak Socialist Republic. A total of 151 scientists attended, from 23 countries and 4 international organizations. The participants heard and discussed more than 60 scientific papers

Closed-cycle gas turbine working fluids

International Nuclear Information System (INIS)

Lee, J.C.; Campbell, J. Jr.; Wright, D.E.

1981-01-01

Characteristic requirements of a closed-cycle gas turbine (CCGT) working fluid were identified and the effects of their thermodynamic and transport properties on the CCGT cycle performance, required heat exchanger surface area and metal operating temperature, cycle operating pressure levels, and the turbomachinery design were investigated. Material compatibility, thermal and chemical stability, safety, cost, and availability of the working fluid were also considered in the study. This paper also discusses CCGT working fluids utilizing mixtures of two or more pure gases. Some mixtures of gases exhibit pronounced synergetic effects on their characteristic properties including viscosity, thermal conductivity and Prandtl number, resulting in desirable heat transfer properties and high molecular weights. 21 refs

Internal Morphologies of Cycled Li-Metal Electrodes Investigated by Nano-Scale Resolution X-ray Computed Tomography.

Science.gov (United States)

Frisco, Sarah; Liu, Danny X; Kumar, Arjun; Whitacre, Jay F; Love, Corey T; Swider-Lyons, Karen E; Litster, Shawn

2017-06-07

While some commercially available primary batteries have lithium metal anodes, there has yet to be a commercially viable secondary battery with this type of electrode. Research prototypes of these cells typically exhibit a limited cycle life before dendrites form and cause internal cell shorting, an occurrence that is more pronounced during high-rate cycling. To better understand the effects of high-rate cycling that can lead to cell failure, we use ex situ nanoscale-resolution X-ray computed tomography (nano-CT) with the aid of Zernike phase contrast to image the internal morphologies of lithium metal electrodes on copper wire current collectors that have been cycled at low and high current densities. The Li that is deposited on a Cu wire and then stripped and deposited at low current density appears uniform in morphology. Those cycled at high current density undergo short voltage transients to >3 V during Li-stripping from the electrode, during which electrolyte oxidation and Cu dissolution from the current collector may occur. The effect of temperature is also explored with separate cycling experiments performed at 5 and 33 °C. The resulting morphologies are nonuniform films filled with voids that are semispherical in shape with diameters ranging from hundreds of nanometers to tens of micrometers, where the void size distributions are temperature-dependent. Low-temperature cycling elicits a high proportion of submicrometer voids, while the higher-temperature sample morphology is dominated by voids larger than 2 μm. In evaluating these morphologies, we consider the importance of nonidealities during extreme charging, such as electrolyte decomposition. We conclude that nano-CT is an effective tool for resolving features and aggressive cycling-induced anomalies in Li films in the range of 100 nm to 100 μm.

Manganese pyridinedicarboxylates: New anode materials for lithium-ion batteries with good cycling performance

Energy Technology Data Exchange (ETDEWEB)

Fei, Hailong, E-mail: feilin09053@gmail.com [College of Chemistry, Fuzhou University, 2 Xueyuan Road, University Town Fuzhou, Fujian 350116 (China); Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Nankai University, Tianjin 300071 (China); Li, Zhiwei; Liu, Xin [College of Chemistry, Fuzhou University, 2 Xueyuan Road, University Town Fuzhou, Fujian 350116 (China)

2015-08-15

Highlights: • Manganese 2,3-pyridinedicarboxylate and 2,5-pyridinedicarboxylate. • Firstly tested as anode materials. • High capacity and good cycle stability. - Abstract: It is significant to discover new environmental friendly, sustainable and renewable electrode materials for lithium-ion batteries. Manganese dicarboxylate [Mn{sub 2}(pdc){sub 2}(H{sub 2}O){sub 3}]{sub n}⋅2nH{sub 2}O (pdc = pyridine-2,3-dicarboxylate) is firstly found to be a high-energy anode material for lithium-ion batteries. It shows a high discharge capacity of 573.7 mA h g{sup −1} for the second cycle between a 0.05 and 3.0 V voltage limit at a discharge current density of 500 mA g{sup −1}. The reversible capacity of 457.2 mA h g{sup −1} is remained after 100 cycles with a capacity retention being 79.6%. In addition, it is found that Mn 2,5-pyridinedicarboxyle was also stable anode materials with high capacity.

Heavy metal oxide glasses as gamma rays shielding material

International Nuclear Information System (INIS)

Kaur, Preet; Singh, Devinder; Singh, Tejbir

2016-01-01

The gamma rays shielding parameters for heavy metal oxide glasses and concrete samples are comparable. However, the transparent nature of glasses provides additional feature to visualize inside the shielding material. Hence, different researchers had contributed in computing/measuring different shielding parameters for different configurations of heavy metal oxide glass systems. In the present work, a detailed study on different heavy metal (_5_6Ba, _6_4Gd, _8_2Pb, _8_3Bi) oxide glasses has been presented on the basis of different gamma rays shielding parameters as reported by different researchers in the recent years. It has been observed that among the selected heavy metal oxide glass systems, Bismuth based glasses provide better gamma rays shielding. Hence, Bismuth based glasses can be better substitute to concrete walls at nuclear reactor sites and nuclear labs.

Heavy metal oxide glasses as gamma rays shielding material

Energy Technology Data Exchange (ETDEWEB)

Kaur, Preet; Singh, Devinder; Singh, Tejbir, E-mail: dr.tejbir@gmail.com

2016-10-15

The gamma rays shielding parameters for heavy metal oxide glasses and concrete samples are comparable. However, the transparent nature of glasses provides additional feature to visualize inside the shielding material. Hence, different researchers had contributed in computing/measuring different shielding parameters for different configurations of heavy metal oxide glass systems. In the present work, a detailed study on different heavy metal ({sub 56}Ba, {sub 64}Gd, {sub 82}Pb, {sub 83}Bi) oxide glasses has been presented on the basis of different gamma rays shielding parameters as reported by different researchers in the recent years. It has been observed that among the selected heavy metal oxide glass systems, Bismuth based glasses provide better gamma rays shielding. Hence, Bismuth based glasses can be better substitute to concrete walls at nuclear reactor sites and nuclear labs.

Rational Design of Two-Dimensional Metallic and Semiconducting Spintronic Materials Based on Ordered Double-Transition-Metal MXenes

KAUST Repository

Dong, Liang

2016-12-30

Two-dimensional (2D) materials that display robust ferromagnetism have been pursued intensively for nanoscale spintronic applications, but suitable candidates have not been identified. Here we present theoretical predictions on the design of ordered double-transition-metal MXene structures to achieve such a goal. On the basis of the analysis of electron filling in transition-metal cations and first-principles simulations, we demonstrate robust ferromagnetism in Ti2MnC2Tx monolayers regardless of the surface terminations (T = O, OH, and F), as well as in Hf2MnC2O2 and Hf2VC2O2 monolayers. The high magnetic moments (3–4 μB/unit cell) and high Curie temperatures (495–1133 K) of these MXenes are superior to those of existing 2D ferromagnetic materials. Furthermore, semimetal-to-semiconductor and ferromagnetic-to-antiferromagnetic phase transitions are predicted to occur in these materials in the presence of small or moderate tensile in-plane strains (0–3%), which can be externally applied mechanically or internally induced by the choice of transition metals.

On Subsurface Crack Growth in Fibre Metal Laminate Materials

National Research Council Canada - National Science Library

Randall, Christian

2003-01-01

Fatigue crack growth in fibre metal laminates (FMLs) is significantly more complex than in monolithic materials due to the interaction of various physical mechanisms that govern the growth of cracks in laminates...

Recent Progress in Some Amorphous Materials for Supercapacitors.

Science.gov (United States)

Li, Qing; Xu, Yuxia; Zheng, Shasha; Guo, Xiaotian; Xue, Huaiguo; Pang, Huan

2018-05-14

A breakthrough in technologies having "green" and sustainable energy storage conversion is urgent, and supercapacitors play a crucial role in this area of research. Owing to their unique porous structure, amorphous materials are considered one of the best active materials for high-performance supercapacitors due to their high specific capacity, excellent cycling stability, and fast charging rate. This Review summarizes the synthesis of amorphous materials (transition metal oxides, carbon-based materials, transition metal sulfides, phosphates, hydroxides, and their complexes) to highlight their electrochemical performance in supercapacitors. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

In silico optimization of phase-change materials for digital memories: a survey of first-row transition-metal dopants for Ge₂Sb₂Te₅.

Science.gov (United States)

Skelton, J M; Elliott, S R

2013-05-22

Phase-change materials are the alloys at the heart of an emerging class of next-generation, non-volatile digital memory technologies. However, the widely studied Ge-Sb-Te system possesses several undesirable properties, and enhancing its properties, e.g. by doping, is an area of active research. Various first-row transition-metal dopants have been shown to impart useful property enhancements, but a systematic study of the entire period has yet to be undertaken, and little has been done to investigate their interaction with the host material at the atomic level. We have carried out first-principles computer simulations of the complete phase-change cycle in Ge2Sb2Te5 doped with each of the ten first-row transition metals. In this article, we present a comprehensive survey of the electronic, magnetic and optical properties of these doped materials. We discuss in detail their atomic-level structure, and relate the microscopic behaviours of the dopant atoms to their influence on the Ge2Sb2Te5 host. By considering an entire family of similar materials, we identify trends and patterns which might be used to predict suitable dopants for optimizing materials for specific phase-change applications. The computational method employed here is general, and this materials-discovery approach could be applied in the future to study other families of potential dopants for such materials.

Electric Resistance Tests on Compacted Clay Material under Dynamic Load Coupled with Dry-Wet Cycling

Directory of Open Access Journals (Sweden)

Zheng Lu

2018-01-01

Full Text Available The study of compacted clay material under dynamic load coupled with dry-wet cycling is one of the most important areas in the field of transportation. In this paper, experiments in terms of compacted clay under dynamic load coupled with dry-wet cycling are performed, and synchronous resistivity tests are also conducted. According to the test results, the influences of cumulative plastic strain, dry-wet cycles, and amplitudes on the soil resistivity are analyzed. Then a new damage factor based on resistivity is proposed to evaluate the long-term performance of compacted clay material. The result of research shows that the evolution of the soil resistivity can be divided into two stages, which has a contrary tendency with that of cumulative plastic strain. The dry-wet cycles and amplitudes have a significant effect on the damage of the compacted soil, which indicates that the dry-wet cycling of compacted soil materials should not be ignored in road engineering, especially in rainy and humid areas.

The effect of environmental conditions on the stability of heavy metal-filter material complex as assessed by the leaching of adsorbed metal ions

Energy Technology Data Exchange (ETDEWEB)

Khokhotva, Oleksandr, E-mail: khokhotva@bigmir.net [School of Sustainable Development of Society and Technology, Maelardalen University, Box 883, SE-721 23, Vaesteras (Sweden); Waara, Sylvia, E-mail: sylvia.waara@hh.se [School of Sustainable Development of Society and Technology, Maelardalen University, Box 883, SE-721 23, Vaesteras (Sweden)

2011-06-15

In this study the influence of environmental conditions, most likely prevailing in filter beds used for intermittently discharged pollutant streams such as landfill leachate and storm water, on the stability of the heavy metal-filter complex was investigated for 2 filter materials; non-treated and urea treated pine bark, using leaching experiments. The metal-filter complex stability was higher for urea treated than for non-treated pine bark and dependent on the metal adsorbed. The type of environmental condition applied was of less importance for the extent of leaching. - Highlights: > Metal-pine bark complex stability under changing environmental conditions is studied. > Metal leaching from non-treated bark is much higher than from urea-treated bark. > No significant influence of changing environmental conditions on the leaching extent. > Metal leaching from wet bark samples exposed to freezing is somewhat higher.> Zn leaching is the highest and Cu leaching is the lowest for both bark samples. - The study assess the metal-filter material complex stability when metal removal using filter material is used in locations with fluctuating environmental conditions.

The effect of environmental conditions on the stability of heavy metal-filter material complex as assessed by the leaching of adsorbed metal ions

International Nuclear Information System (INIS)

Khokhotva, Oleksandr; Waara, Sylvia

2011-01-01

In this study the influence of environmental conditions, most likely prevailing in filter beds used for intermittently discharged pollutant streams such as landfill leachate and storm water, on the stability of the heavy metal-filter complex was investigated for 2 filter materials; non-treated and urea treated pine bark, using leaching experiments. The metal-filter complex stability was higher for urea treated than for non-treated pine bark and dependent on the metal adsorbed. The type of environmental condition applied was of less importance for the extent of leaching. - Highlights: → Metal-pine bark complex stability under changing environmental conditions is studied. → Metal leaching from non-treated bark is much higher than from urea-treated bark. → No significant influence of changing environmental conditions on the leaching extent. → Metal leaching from wet bark samples exposed to freezing is somewhat higher.→ Zn leaching is the highest and Cu leaching is the lowest for both bark samples. - The study assess the metal-filter material complex stability when metal removal using filter material is used in locations with fluctuating environmental conditions.

Macro and Microscopic Investigation on Fracture Specimen of Alloy 617 Base Metal and Weldment in Low Cycle Fatigue Regime

International Nuclear Information System (INIS)

Kim, Seon Jin; Dewa, Rando Tungga; Kim, Won Gon

2016-01-01

This paper investigates macro- and microscopic fractography performed on fracture specimens from low cycle fatigue (LCF) testings through an Alloy 617 base metal and weldments. The weldment specimens were taken from gas tungsten arc welding (GTAW) pad of Alloy 617. The aim of the present study is to investigate the macro- and microscopic aspects of the low cycle fatigue fracture mode and mechanism of Alloy 617 base metal and GTAWed weldment specimens. Fully axial total strain controlled fatigue tests were conducted at room temperature with total strain ranges of 0.6, 0.9, 1.2 and 1.5%. Macroscopic fracture surfaces of Alloy 617 base metal specimens showed a flat type normal to the fatigue loading direction, whereas the GTAWed weldment specimens were of a shear/star type. The fracture surfaces of both the base metal and weldment specimens revealed obvious fatigue striations at the crack propagation regime. In addition, the fatigue crack mechanism of the base metal showed a transgranular normal to fatigue loading direction; however, the GTAWed weldment specimens showed a transgranular at approximately 45° to the fatigue loading direction

Macro and Microscopic Investigation on Fracture Specimen of Alloy 617 Base Metal and Weldment in Low Cycle Fatigue Regime

Energy Technology Data Exchange (ETDEWEB)

Kim, Seon Jin; Dewa, Rando Tungga [Pukyung National Univ., Busan (Korea, Republic of); Kim, Won Gon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2016-06-15

This paper investigates macro- and microscopic fractography performed on fracture specimens from low cycle fatigue (LCF) testings through an Alloy 617 base metal and weldments. The weldment specimens were taken from gas tungsten arc welding (GTAW) pad of Alloy 617. The aim of the present study is to investigate the macro- and microscopic aspects of the low cycle fatigue fracture mode and mechanism of Alloy 617 base metal and GTAWed weldment specimens. Fully axial total strain controlled fatigue tests were conducted at room temperature with total strain ranges of 0.6, 0.9, 1.2 and 1.5%. Macroscopic fracture surfaces of Alloy 617 base metal specimens showed a flat type normal to the fatigue loading direction, whereas the GTAWed weldment specimens were of a shear/star type. The fracture surfaces of both the base metal and weldment specimens revealed obvious fatigue striations at the crack propagation regime. In addition, the fatigue crack mechanism of the base metal showed a transgranular normal to fatigue loading direction; however, the GTAWed weldment specimens showed a transgranular at approximately 45° to the fatigue loading direction.

Liquid Metals as Plasma-facing Materials for Fusion Energy Systems: From Atoms to Tokamaks

Energy Technology Data Exchange (ETDEWEB)

Stone, Howard A. [Princeton Univ., NJ (United States); Koel, Bruce E. [Princeton Univ., NJ (United States); Bernasek, Steven L. [Princeton Univ., NJ (United States); Carter, Emily A. [Princeton Univ., NJ (United States); Debenedetti, Pablo G. [Princeton Univ., NJ (United States); Panagiotopoulos, Athanassios Z. [Princeton Univ., NJ (United States)

2017-06-23

The objective of our studies was to advance our fundamental understanding of liquid metals as plasma-facing materials for fusion energy systems, with a broad scope: from atoms to tokamaks. The flow of liquid metals offers solutions to significant problems of the plasma-facing materials for fusion energy systems. Candidate metals include lithium, tin, gallium, and their eutectic combinations. However, such liquid metal solutions can only be designed efficiently if a range of scientific and engineering issues are resolved that require advances in fundamental fluid dynamics, materials science and surface science. In our research we investigated a range of significant and timely problems relevant to current and proposed engineering designs for fusion reactors, including high-heat flux configurations that are being considered by leading fusion energy groups world-wide. Using experimental and theoretical tools spanning atomistic to continuum descriptions of liquid metals, and bridging surface chemistry, wetting/dewetting and flow, our research has advanced the science and engineering of fusion energy materials and systems. Specifically, we developed a combined experimental and theoretical program to investigate flows of liquid metals in fusion-relevant geometries, including equilibrium and stability of thin-film flows, e.g. wetting and dewetting, effects of electromagnetic and thermocapillary fields on liquid metal thin-film flows, and how chemical interactions and the properties of the surface are influenced by impurities and in turn affect the surface wetting characteristics, the surface tension, and its gradients. Because high-heat flux configurations produce evaporation and sputtering, which forces rearrangement of the liquid, and any dewetting exposes the substrate to damage from the plasma, our studies addressed such evaporatively driven liquid flows and measured and simulated properties of the different bulk phases and material interfaces. The range of our studies

Recycling cycle of materials applied to acrylonitrile-butadiene-styrene/policarbonate blends with styrene-butadiene-styrene copolymer addition

Science.gov (United States)

Cândido, L. H. A.; Ferreira, D. B.; Júnior, W. Kindlein; Demori, R.; Mauler, R. S.

2014-05-01

The scope of this research is the recycling of polymers from mobile phones hulls discarded and the performance evaluation when they are submitted to the Recycling Cycle of Materials (RCM). The studied material was the ABS/PC blend in a 70/30 proportion. Different compositions were evaluated adding virgin material, recycled material and using the copolymer SBS as impact modifier. In order to evaluate the properties of material's composition, the samples were characterized by TGA, FTIR, SEM, IZOD impact strength and tensile strength tests. At the first stage, the presented results suggest the composition containing 25% of recycled material and 5% of SBS combines good mechanical performance to the higher content of recycled material and lower content of impact modifier providing major benefits to recycling plans. Five cycles (RCM) were applied in the second stage; they evidenced a decrease trend considering the impact strength. At first and second cycle the impact strength was higher than reference material (ABS/PC blend) and from the fourth cycle it was lower. The superiority impact strength in the first and second cycles can be attributed to impact modifier effect. The thermal tests and the spectrometry didn't show the presence of degradation process in the material and the TGA curves demonstrated the process stability. The impact surface of each sample was observed at SEM. The microstructures are not homogeneous presenting voids and lamellar appearance, although the outer surface presents no defects, demonstrating good moldability. The present work aims to assess the life cycle of the material from the successive recycling processes.

Corrosion behaviour of metallic and non-metallic materials in various media in the Anhydrite and Gypsum Mine Felsenau/AG

International Nuclear Information System (INIS)

Laske, D.; Wiedemann, K.H.

1983-10-01

The final underground disposal of radioactive wastes necessitates container materials with a good long-term resistance against corrosion from both external agents and the solidification matrix inside. For low- and medium-level active waste, repositories in anhydrite sites, among others, are under consideration. Sheet and plate samples from 14 metallic and 8 non-metallic materials have been tested for 5 years in a tunnel in the Anhydrite and Gypsum Mine Felsenau/AG for their corrosion resistance in the tunnel atmosphere, anhydrite powder, gypsum powder, gypsum, and cement. From the metallic materials tested, only chromium-nickel steel is corrosion resistant to all the media present. Zinc plated and tin plated iron sheet as well as aluminium and aluminium alloys are corrosion resistant only in the atmosphere of the tunnel, and lead plated iron sheet is resistant also in cement. Aluminium is dissolved in cement. Uncovered iron sheet undergoes severe corrosion. The non-metallic coatings tested (lacquer, stove lacquer, or synthetic resins) partially flake off already after one year's testing and are therefore not appropriate for iron sheet corrosion protection. No influence of the different media has been observed after 5 years on the 8 plastic materials tested (6 without, and 2 with glass fiber reinforcement). (author)

Fungal nanoscale metal carbonates and production of electrochemical materials.

Science.gov (United States)

Li, Qianwei; Gadd, Geoffrey Michael

2017-09-01

Fungal biomineralization of carbonates results in metal removal from solution or immobilization within a solid matrix. Such a system provides a promising method for removal of toxic or valuable metals from solution, such as Co, Ni, and La, with some carbonates being of nanoscale dimensions. A fungal Mn carbonate biomineralization process can be applied for the synthesis of novel electrochemical materials. © 2017 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

Metal corrosion in a supercritical carbon dioxide - liquid sodium power cycle.

Energy Technology Data Exchange (ETDEWEB)

Moore, Robert Charles; Conboy, Thomas M.

2012-02-01

A liquid sodium cooled fast reactor coupled to a supercritical carbon dioxide Brayton power cycle is a promising combination for the next generation nuclear power production process. For optimum efficiency, a microchannel heat exchanger, constructed by diffusion bonding, can be used for heat transfer from the liquid sodium reactor coolant to the supercritical carbon dioxide. In this work, we have reviewed the literature on corrosion of metals in liquid sodium and carbon dioxide. The main conclusions are (1) pure, dry CO{sub 2} is virtually inert but can be highly corrosive in the presence of even ppm concentrations of water, (2) carburization and decarburization are very significant mechanism for corrosion in liquid sodium especially at high temperature and the mechanism is not well understood, and (3) very little information could be located on corrosion of diffusion bonded metals. Significantly more research is needed in all of these areas.

Nuclear fuel cycle: research and development and push technologies

International Nuclear Information System (INIS)

Oliveira, Wagner dos Santos

2002-01-01

The scope of this work is to show the importance of 'push technologies in the development of the Nuclear Fuel Cycle more specifically the so called 'Projeto Conversao' PROCON. This R and D activities lead to the design of special equipment, new metallic and polymer materials. (author)

Practicalization strategic research of FBR cycle

International Nuclear Information System (INIS)

2000-01-01

Practicalization strategic research of FBR cycle consists of two phases such as phase I (FY 1999-2000) and phase II (to FY 2005). In every phase, research and development plants and results are checked and reviewed. The assessment indexes are five development objects such as safety, economical efficiency, resource effective utilization, environmental load decrease and nuclear non-proliferation and technical realization, too. Reactor core, FBR plant system and fuel cycle system are investigated. We selected the research subjects of cooling materials as sodium, heavy metals (lead and lead bismuth alloy), gas (carbon dioxide and helium) and water (boiling water, power water and supercritical pressure water) and fuel types as cladding tube fuel (oxide, nitride and metal) and coated fuel particle (oxide and nitride) for helium gas cooling reactor. In FY1999, the good reactor core and FBR plant system for every cooling materials are studied. Two reprocessing (a wet reprocessing using aqueous solution and a dry method) were selected. In FY 2000, we will investigate effects of throughput, plant concept and cost and evaluate achievement of development objects and then decide the development plan. (S.Y.)

Accounting of media conditions in the Life Cycle Impact Assessment of Metals on Aquatic Ecosystems

DEFF Research Database (Denmark)

Birkved, Morten; Payet, Jerome

2003-01-01

Impact from metals play a major role in all Life Cycle Impact Assessment (LCIA) studies. Nevertheless, LCIA methods are typically not adapted for such compounds ignoring problems of speciation and bioavailability. Current uncertainty on metal toxicity estimates are on average twice as high...... of the influence of media condition on the toxicity : Partial Least Square projection to latent Structure Regression (PLSR) was carried out to estimate the relative variable importance and linear regression was used to, identify the relation between media parameters the response of Daphnia magna....

Porous carbon-coated ZnO nanoparticles derived from low carbon content formic acid-based Zn(II) metal-organic frameworks towards long cycle lithium-ion anode material

International Nuclear Information System (INIS)

Gao, Song; Fan, Ruiqing; Li, Bingjiang; Qiang, Liangsheng; Yang, Yulin

2016-01-01

Graphical abstract: The nanocomposites constructed from Zn-based MOFs exhibit low carbon content with super-high rate capability and long cycling life. - Highlights: • Novel ZnO@porous carbon matrix nanocomposites are constructed by pyrolysis of Zn-based MOFs. • The nanocomposites constructed with Zn-based MOFs show low carbon content. • The constructed nanocomposites exhibit high energy density, super-high rate capability and long cycling life. - Abstract: Single-C formic acid-based metal-organic frameworks (MOFs) are used to construct novel ZnO@porous carbon matrix nanocomposites by controlled pyrolysis. In the constructed nanocomposites, the porous carbon matrices act as a confined support to prevent agglomeration of the ZnO nanoparticles and create a rapid electron conductive network. Meanwhile, the well-defined, continuous porous structured MOFs provide a large specific surface area, which increases the contact of electrolyte-electrode and improves the penetration of electrolyte. Especially, the reasonable choice of formic acid-based MOFs construct the low carbon content composite, which contribute to the high energy density and long cycle life. The constructed nanocomposites show stable, ultrahigh rate lithium ion storage properties of 650 mAh g −1 at charge/discharge rate of 1 C even after 200 cycles.

New half-metallic materials with an alkaline earth element

International Nuclear Information System (INIS)

Kusakabe, Koichi; Geshi, Masaaki; Tsukamoto, Hidekazu; Suzuki, Naoshi

2004-01-01

New candidates for half-metallic materials were theoretically designed recently by Geshi et al. The materials are calcium pnictides, i.e. CaP, CaAs and CaSb. When the zinc-blende structure was assumed, these compounds showed half-metallic electronic band-structure, in which a curious flat band was found. To explain this magnetism, we investigated characters of orbitals on this flat band of CaAs. The hybridization of p states of As with d states of Ca is shown to be essential for formation of a flat band made of localized orbitals. The appearance of complete spin polarization in the flat band suggests that the flat-band mechanism is relevant for the ferromagnetism. A connection from the first-principles result to a solvable Hubbard model with a flat band is discussed

Recycle and reuse of materials and components from waste streams of nuclear fuel cycle facilities

International Nuclear Information System (INIS)

2000-01-01

All nuclear fuel cycle processes utilize a wide range of equipment and materials to produce the final products they are designed for. However, as at any other industrial facility, during operation of the nuclear fuel cycle facilities, apart from the main products some byproducts, spent materials and waste are generated. A lot of these materials, byproducts or some components of waste have a potential value and may be recycled within the original process or reused outside either directly or after appropriate treatment. The issue of recycle and reuse of valuable material is important for all industries including the nuclear fuel cycle. The level of different materials involvement and opportunities for their recycle and reuse in nuclear industry are different at different stages of nuclear fuel cycle activity, generally increasing from the front end to the back end processes and decommissioning. Minimization of waste arisings and the practice of recycle and reuse can improve process economics and can minimize the potential environmental impact. Recognizing the importance of this subject, the International Atomic Energy Agency initiated the preparation of this report aiming to review and summarize the information on the existing recycling and reuse practice for both radioactive and non-radioactive components of waste streams at nuclear fuel cycle facilities. This report analyses the existing options, approaches and developments in recycle and reuse in nuclear industry

Solvent properties of hydrazine in the preparation of metal chalcogenide bulk materials and films.

Science.gov (United States)

Yuan, Min; Mitzi, David B

2009-08-21

A combination of unique solvent properties of hydrazine enables the direct dissolution of a range of metal chalcogenides at ambient temperature, rendering this an extraordinarily simple and soft synthetic approach to prepare new metal chalcogenide-based materials. The extended metal chalcogenide parent framework is broken up during this process, and the resulting metal chalcogenide building units are re-organized into network structures (from 0D to 3D) based upon their interactions with the hydrazine/hydrazinium moieties. This Perspective will review recent crystal and materials chemistry developments within this family of compounds and will briefly discuss the utility of this approach in metal chalcogenide thin-film deposition.

Fluorine uptake into human enamel around a fluoride-containing dental material during cariogenic pH cycling

International Nuclear Information System (INIS)

Komatsu, H.; Yamamoto, H.; Nomachi, M.; Yasuda, K.; Matsuda, Y.; Murata, Y.; Kijimura, T.; Sano, H.; Sakai, T.; Kamiya, T.

2007-01-01

Using PIGE (TIARA, JAPAN) technique, we measured fluorine (F) uptake into the tooth enamel around a fluoride-containing material during caries progression using pH cycling. Class I cavities in the buccal surfaces of 6 extracted human teeth were drilled and filled with fluoride-containing material; a glass ionomer cement (Fuji IX(GC)). Three 300 μm sections through the material were obtained from each tooth. Two of these specimens were utilized to measure the F distribution in enamel adjacent to the material. A 1.7 MeV proton beam accelerated by the TIARA single-ended accelerator was delivered to a micro-beam apparatus. The beam spot size was about 1 μm with a beam current of about 100 pA. A nuclear reaction, 19 F(p, αγ) 16 0, was used to measure the F concentration and the gamma-rays from this reaction were detected with a 4' NaI detector. X-rays induced by proton were detected with a Si(Li) detector to measure calcium concentration and the beam intensity was monitored with the X-ray yield from a copper foil for quantitative analysis. After measurement of F uptake, all specimens were polished to a thickness of 120 μm. In order to simulate daily acid challenges occurring in the oral cavity, the pH cycling (pH6.8-pH4.5) was carried out for 1, 3 and 5 weeks, separately. The duration that the solution remained below pH 5.5 was 37 min per cycle. The cycles were repeated 6 times per day with 2 h interval between cycles, and the specimens were kept in remineralizing solution for the rest of pH cycle. After pH cycling, F and calcium distribution of each specimen was evaluated using PIGE technique. The F distribution of the specimens before pH cycling clearly showed the F uptake from fluoride-containing material into enamel adjacent to the material. After pH cycling, the caries progression in all specimens was observed by the image of transverse microradiography (TMR). The depth of caries and mineral loss progressed with increasing the duration of pH cycling, although

Fluorine uptake into human enamel around a fluoride-containing dental material during cariogenic pH cycling

Energy Technology Data Exchange (ETDEWEB)

Komatsu, H. [Graduate School of Dental Medicine, Hokkaido University, Kita-13, Nishi-7, Kita-ku, Sapporo 060-8586 (Japan)]. E-mail: kom@den.hokudai.ac.jp; Yamamoto, H. [Graduate School of Dentistry, Osaka University, 1-8 Yamada-Oka, Suita 565-0871 (Japan); Nomachi, M. [Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka 560-0043 (Japan); Yasuda, K. [Wakasa wan Energy Research Center, 64-52-1 Hase, Tsuruga 914-0192 (Japan); Matsuda, Y. [Graduate School of Dental Medicine, Hokkaido University, Kita-13, Nishi-7, Kita-ku, Sapporo 060-8586 (Japan); Murata, Y. [Graduate School of Dental Medicine, Hokkaido University, Kita-13, Nishi-7, Kita-ku, Sapporo 060-8586 (Japan); Kijimura, T. [Graduate School of Dental Medicine, Hokkaido University, Kita-13, Nishi-7, Kita-ku, Sapporo 060-8586 (Japan); Sano, H. [Graduate School of Dental Medicine, Hokkaido University, Kita-13, Nishi-7, Kita-ku, Sapporo 060-8586 (Japan); Sakai, T. [Takasaki Advanced Radiation Research Institute, JAEA, 1233 Watanuki-machi, Takasaki 370-1292 (Japan); Kamiya, T. [Takasaki Advanced Radiation Research Institute, JAEA, 1233 Watanuki-machi, Takasaki 370-1292 (Japan)

2007-07-15

Using PIGE (TIARA, JAPAN) technique, we measured fluorine (F) uptake into the tooth enamel around a fluoride-containing material during caries progression using pH cycling. Class I cavities in the buccal surfaces of 6 extracted human teeth were drilled and filled with fluoride-containing material; a glass ionomer cement (Fuji IX(GC)). Three 300 {mu}m sections through the material were obtained from each tooth. Two of these specimens were utilized to measure the F distribution in enamel adjacent to the material. A 1.7 MeV proton beam accelerated by the TIARA single-ended accelerator was delivered to a micro-beam apparatus. The beam spot size was about 1 {mu}m with a beam current of about 100 pA. A nuclear reaction, {sup 19}F(p, {alpha}{gamma}){sup 16}0, was used to measure the F concentration and the gamma-rays from this reaction were detected with a 4' NaI detector. X-rays induced by proton were detected with a Si(Li) detector to measure calcium concentration and the beam intensity was monitored with the X-ray yield from a copper foil for quantitative analysis. After measurement of F uptake, all specimens were polished to a thickness of 120 {mu}m. In order to simulate daily acid challenges occurring in the oral cavity, the pH cycling (pH6.8-pH4.5) was carried out for 1, 3 and 5 weeks, separately. The duration that the solution remained below pH 5.5 was 37 min per cycle. The cycles were repeated 6 times per day with 2 h interval between cycles, and the specimens were kept in remineralizing solution for the rest of pH cycle. After pH cycling, F and calcium distribution of each specimen was evaluated using PIGE technique. The F distribution of the specimens before pH cycling clearly showed the F uptake from fluoride-containing material into enamel adjacent to the material. After pH cycling, the caries progression in all specimens was observed by the image of transverse microradiography (TMR). The depth of caries and mineral loss progressed with increasing the

Microstructure and mechanical properties of metallic high-temperature materials. Research report

International Nuclear Information System (INIS)

Mughrabi, H.; Gottstein, G.; Mecking, H.; Riedel, H.; Toboloski, J.

1999-01-01

This volume contains 38 lectures of research studies performed in the course of the Priority Programme 'Microstructure and Mechanical Properties of Metallic High-Temperature Materials' supported by the Deutsche Forschungsgemeinschaft (DFG) over a period of six years from 1991 to 1997. The four materials selected were: 1. light metal PM-aluminium and titanium base alloys; 2. ferritic chromium and austenitic alloy 800 steels; 3. (monocrystalline) nickel-base superalloys; and 4. nickel- and iron-base oxide-dispersion-strengthened superalloys. All papers have been abstracted separately for the ENERGY database

Efficient waveguide coupler based on metal materials

Science.gov (United States)

Wu, Wenjun; Yang, Junbo; Chang, Shengli; Zhang, Jingjing; Lu, Huanyu

2015-10-01

Because of the diffraction limit of light, the scale of optical element stays in the order of wavelength, which makes the interface optics and nano-electronic components cannot be directly matched, thus the development of photonics technology encounters a bottleneck. In order to solve the problem that coupling of light into the subwavelength waveguide, this paper proposes a model of coupler based on metal materials. By using Surface Plasmon Polaritons (SPPs) wave, incident light can be efficiently coupled into waveguide of diameter less than 100 nm. This paper mainly aims at near infrared wave band, and tests a variety of the combination of metal materials, and by changing the structural parameters to get the maximum coupling efficiency. This structure splits the plane incident light with wavelength of 864 nm, the width of 600 nm into two uniform beams, and separately coupled into the waveguide layer whose width is only about 80 nm, and the highest coupling efficiency can reach above 95%. Using SPPs structure will be an effective method to break through the diffraction limit and implement photonics device high-performance miniaturization. We can further compress the light into small scale fiber or waveguide by using the metal coupler, and to save the space to hold more fiber or waveguide layer, so that we can greatly improve the capacity of optical communication. In addition, high-performance miniaturization of the optical transmission medium can improve the integration of optical devices, also provide a feasible solution for the photon computer research and development in the future.

Method and apparatus for fabricating a composite structure consisting of a filamentary material in a metal matrix

Science.gov (United States)

Banker, J.G.; Anderson, R.C.

1975-10-21

A method and apparatus are provided for preparing a composite structure consisting of filamentary material within a metal matrix. The method is practiced by the steps of confining the metal for forming the matrix in a first chamber, heating the confined metal to a temperature adequate to effect melting thereof, introducing a stream of inert gas into the chamber for pressurizing the atmosphere in the chamber to a pressure greater than atmospheric pressure, confining the filamentary material in a second chamber, heating the confined filamentary material to a temperature less than the melting temperature of the metal, evacuating the second chamber to provide an atmosphere therein at a pressure, placing the second chamber in registry with the first chamber to provide for the forced flow of the molten metal into the second chamber to effect infiltration of the filamentary material with the molten metal, and thereafter cooling the metal infiltrated-filamentary material to form said composite structure.

Method and apparatus for fabricating a composite structure consisting of a filamentary material in a metal matrix

International Nuclear Information System (INIS)

Banker, J.G.; Anderson, R.C.

1975-01-01

A method and apparatus are provided for preparing a composite structure consisting of filamentary material within a metal matrix. The method is practiced by the steps of confining the metal for forming the matrix in a first chamber, heating the confined metal to a temperature adequate to effect melting thereof, introducing a stream of inert gas into the chamber for pressurizing the atmosphere in the chamber to a pressure greater than atmospheric pressure, confining the filamentary material in a second chamber, heating the confined filamentary material to a temperature less than the melting temperature of the metal, evacuating the second chamber to provide an atmosphere therein at a pressure, placing the second chamber in registry with the first chamber to provide for the forced flow of the molten metal into the second chamber to effect infiltration of the filamentary material with the molten metal, and thereafter cooling the metal infiltrated-filamentary material to form said composite structure

Technical Meeting on Liquid Metal Reactor Concepts: Core Design and Structural Materials. Working Material

International Nuclear Information System (INIS)

2013-01-01

The objective of the TM on “Liquid metal reactor concept: core design and structural materials” was to present and discuss innovative liquid metal fast reactor (LMFR) core designs with special focus on the choice, development, testing and qualification of advanced reactor core structural materials. Main results arising from national and international R&D programmes and projects in the field were reviewed, and new activities to be carried out under the IAEA aegis were identified on the basis of the analysis of current research and technology gaps

Analysis of the fractures of metallic materials using optical coherence tomography

Science.gov (United States)

Hutiu, Gh.; Duma, V.-F.; Demian, D.; Bradu, A.; Podoleanu, A. Gh.

2017-06-01

Forensic in situ investigations, for example for aviation, maritime, road, or rail accidents would benefit from a method that may allow to distinguish ductile from brittle fractures of metals - as material defects are one of the potential causes of such accidents. Currently, the gold standard in material studies is represented by scanning electron microscopy (SEM). However, SEM are large, lab-based systems, therefore in situ measurements are excluded. In addition, they are expensive and time-consuming. We have approached this problem and propose the use of Optical Coherence Tomography (OCT) in such investigations in order to overcome these disadvantages of SEM. In this respect, we demonstrate the capability to perform such fracture analysis by obtaining the topography of metallic surfaces using OCT. Different materials have been analyzed; in this presentation a sample of low soft carbon steel with the chemical composition of C 0.2%, Mn 1.15%, S 0.04%, P 0.05 % and Fe for the rest has been considered. An in-house developed Swept Source (SS) OCT system has been used, and height profiles have been generated for the sample surface. This profile allowed for concluding that the carbon steel sample was subjected to a ductile fracture. A validation of the OCT images obtained with a 10 microns resolution has been made with SEM images obtained with a 4 nm resolution. Although the OCT resolution is much lower than the one of SEM, we thus demonstrate that it is sufficient in order to obtain clear images of the grains of the metallic materials and thus to distinguish between ductile and brittle fractures. This study analysis opens avenues for a range of applications, including: (i) to determine the causes that have generated pipe ruptures, or structural failures of metallic bridges and buildings, as well as damages of machinery parts; (ii) to optimize the design of various machinery; (iii) to obtain data regarding the structure of metallic alloys); (iv) to improve the

Effect of metals on the lytic cycle of the coccolithovirus, EhV86.

Directory of Open Access Journals (Sweden)

Martha eGledhill

2012-04-01

Full Text Available In this study we show that metals, and in particular copper (Cu, can disrupt the lytic cycle in the Emiliania huxleyi - EhV86 host-virus system. Numbers of virus particles produced per E. huxleyi cell and E. huxleyi lysis rates were reduced by Cu at total metal concentrations over 500 nM in the presence of EDTA (ethylenediaminetetraacetic acid, and 250 nM in the absence of EDTA in acute short term exposure experiments. Zinc (Zn, cadmium (Cd and cobalt (Co were not observed to affect the lysis rate of EhV86 in these experiments. The cellular glutathione (GSH content increased in virus infected cells, but not as a result of metal exposure. In contrast, the cellular content of phytochelatins (PCs increased only in response to metal exposure. The increase in gluthatione content is consistent with increases in the production of reactive oxygen species (ROS on viral infection, while increases in PC content are likely linked to metal homeostasis and indicate that metal toxicity to the host was not affected by viral infection. We propose that Cu prevents lytic production of EhV86 by interfering with virus DNA (deoxyribonucleic acid synthesis through a transcriptional block, which ultimately suppresses the formation of ROS, a biochemical response required for successful virus infection.

Alkali metal protective garment and composite material

Science.gov (United States)

Ballif, III, John L.; Yuan, Wei W.

1980-01-01

A protective garment and composite material providing satisfactory heat resistance and physical protection for articles and personnel exposed to hot molten alkali metals, such as sodium. Physical protection is provided by a continuous layer of nickel foil. Heat resistance is provided by an underlying backing layer of thermal insulation. Overlying outer layers of fireproof woven ceramic fibers are used to protect the foil during storage and handling.

Method of quantitative analysis of superconducting metal-conducting composite materials

International Nuclear Information System (INIS)

Bogomolov, V.N.; Zhuravlev, V.V.; Petranovskij, V.P.; Pimenov, V.A.

1990-01-01

Technique for quantitative analysis of superconducting metal-containing composite materials, SnO 2 -InSn, WO 3 -InW, Zn)-InZn in particular, has been developed. The method of determining metal content in a composite is based on the dependence of superconducting transition temperature on alloy composition. Sensitivity of temperature determination - 0.02K, error of analysis for InSn system - 0.5%

Dilute NiO/carbon nanofiber composites derived from metal organic framework fibers as electrode materials for supercapacitors

Energy Technology Data Exchange (ETDEWEB)

Yang, Ying; Yang, Feng; Hu, Hongru; Lee, Sungsik; Wang, Yue; Zhao, Hairui; Zeng, Dehong; Zhou, Biao; Hao, Shijie

2017-01-01

A new type of carbon nanofiber (CNF) dominated electrode materials decorated with dilute NiO particles (NiO/CNF) has been in situ fabricated by direct pyrolysis of Ni, Zn-containing metal organic framework fibers, which are skillfully constructed by assembling different proportional NiCl2·6H2O and Zn(Ac)2·2H2O with trimesic acid in the presence of N,N-dimethylformamide. With elegant combination of advantages of CNF and evenly dispersed NiO particles, as well as successful modulation of conductivity and porosity of final composites, our NiO/CNF composites display well-defined capacitive features. A high capacitance of 14926 F g–1 was obtained in 6 M KOH electrolyte when the contribution from 0.43 wt% NiO was considered alone, contributing to over 35% of the total capacitance (234 F g–1 ). This significantly exceeds its theoretical specific capacitance of 2584 F g–1. It has been established from the Ragone plot that a largest energy density of 33.4 Wh kg–1 was obtained at the current density of 0.25 A g–1. Furthermore, such composite electrode materials show good rate capability and outstanding cycling stability up to 5000 times (only 10% loss). The present study provides a brand-new approach to design a high capacitance and stable supercapacitor electrode and the concept is extendable to other composite materials. Keywords: Metal organic framework; Nickel oxide; Carbon nanofiber; In situ synthesis; Capacitance

Degradation of materials under conditions of thermochemical cycles for hydrogen production - part III

International Nuclear Information System (INIS)

Klimas, S.J.; Searle, H.; Guerout, F.

2011-01-01

A capsule method was employed to screen a number of materials for degradation under selected conditions of the sulphur-iodine (SI) and the copper-chlorine (Cu-Cl) thermochemical cycles. A summary of the results of an experimental investigation is given. The recommendations for the selection of the materials required for the construction of the electrolyser subsystem of the copper chlorine hybrid cycle are presented and discussed with the associated rationale. Some remaining uncertainties are illustrated on the basis of the experimental evidence gathered. (author)

Crosslinked Carbon Nanotubes/Polyaniline Composites as a Pseudocapacitive Material with High Cycling Stability

Directory of Open Access Journals (Sweden)

Dong Liu

2015-06-01

Full Text Available The poor cycling stability of polyaniline (PANI limits its practical application as a pseudocapacitive material due to the volume change during the charge-discharge procedure. Herein, crosslinked carbon nanotubes/polyaniline (C-CNTs/PANI composites had been designed by the in situ chemical oxidative polymerization of aniline in the presence of crosslinked carbon nanotubes (C-CNTs, which were obtained by coupling of the functionalized carbon nanotubes with 1,4-benzoquinone. The composite showed a specific capacitance of 294 F/g at the scan rate of 10 mV/s, and could retain 95% of its initial specific capacitance after 1000 CV cycles. Such high electrochemical cycling stability resulting from the crosslinked skeleton of the C-CNTs makes them potential electrode materials for a supercapacitor.

Effects of different drying processes on the concentrations of metals and metalloids in plant materials

International Nuclear Information System (INIS)

Anawar, H.M.; Canha, N.; Freitas, M.C; Santa Regina, I.; Garcia-Sanchez, A.

2011-01-01

The drying process of fresh plant materials may affect the porous structure, dehydration and a number of quality characteristics of these materials. Therefore, this study has investigated the effect of different drying processes on the variation of metal and metalloid concentrations in the dried plant materials. Seven varieties of native plant species collected from Sao Domingos mine were analyzed by instrumental neutron activation analysis (INAA) to investigate the effects of freeze-drying (FD), ambient air-drying (AAD) and oven-drying (OD) process on the concentrations of metals and metalloids in the plant biomass. Comparison of ambient air-dried, oven-dried and freeze-dried preparations allows a phenomenological description of the dehydration artefacts. In the quantitative analysis of metals and metalloids, FD and OD plant samples show the higher concentrations of metals and metalloids when compared to those in the AAD plant biomass. The freeze-drying process is comparatively reliable for determination of metals and metalloids concentrations in plant materials. (author)

Influence of freeze-thaw cycling on the resilient modulues of PFBC materials

Energy Technology Data Exchange (ETDEWEB)

Wolfe, W.E.; Butalia, T.S.; Meek, B.L. [Ohio State University, Columbus, OH (United States). Dept. of Civil and Environmental Engineering and Geodetic Science

1999-01-01

The dynamic stress-strain characteristics of a Pressurized Fluidized Bed Combustion (PFBC) material, before and after freeze and thaw cycling, were studied to evaluate its suitability as a substitute for conventional road construction materials in the design of flexible pavement systems. Samples compacted in the laboratory at two different moisture contents (optimum and 8% above optimum) were cyclically load tested after being allowed to cure for various duration. The results of the cyclic tests are presented in terms of the Resilient Modulus, which is a measure of the elastic property of the soil supporting the roadway. The modulus of the samples compacted near the optimum moisture content compared satisfactorily with data available for conventional materials. Samples compacted at moisture contents higher than the optimum exhibited a significant reduction in a resilient modulus values after freeze-thaw cycling. This comparing indicates that properly compacted PFBC holds good promise as a subgrade material in the construction of low traffic volume roads. 13 refs., 5 figs., 1 tab.

Heavy metals adsorption by novel EDTA-modified chitosan-silica hybrid materials.

Science.gov (United States)

Repo, Eveliina; Warchoł, Jolanta K; Bhatnagar, Amit; Sillanpää, Mika

2011-06-01

Novel adsorbents were synthesized by functionalizing chitosan-silica hybrid materials with (ethylenediaminetetraacetic acid) EDTA ligands. The synthesized adsorbents were found to combine the advantages of both silica gel (high surface area, porosity, rigid structure) and chitosan (surface functionality). The Adsorption potential of hybrid materials was investigated using Co(II), Ni(II), Cd(II), and Pb(II) as target metals by varying experimental conditions such as pH, contact time, and initial metal concentration. The kinetic results revealed that the pore diffusion process played a key role in adsorption kinetics, which might be attributed to the porous structure of synthesized adsorbents. The obtained maximum adsorption capacities of the hybrid materials for the metal ions ranged from 0.25 to 0.63 mmol/g under the studied experimental conditions. The adsorbent with the highest chitosan content showed the best adsorption efficiency. Bi-Langmuir and Sips isotherm model fitting to experimental data suggested the surface heterogeneity of the prepared adsorbents. In multimetal solutions, the hybrid adsorbents showed the highest affinity toward Pb(II). Copyright © 2011 Elsevier Inc. All rights reserved.

Methodologies for evaluating the proliferation resistance of nuclear fuel cycles

International Nuclear Information System (INIS)

Shiotani, Hiroki; Hori, Kei-ichiro; Takeda, Hiroshi

2001-01-01

The Japan Nuclear Cycle Development Institute (JNC) believes that the development of future nuclear fuel cycle technology should be conducted with careful consideration given to non-proliferation. JNC is studying methodologies for evaluating proliferation resistance of nuclear fuel cycle technologies. However, it is difficult to establish the methodology for evaluating proliferation resistance since the results greatly depend on the assumption for the evaluation and the surrounding conditions. This study grouped factors of proliferation resistance into categories through reviewing past studies and studied the relationships between the factors. Then, this study tried to find vulnerable nuclear material (plutonium) in some FBR fuel cycles from the proliferation perspective, and calculated the time it takes to convert the materials from various nuclear fuel cycles into pure plutonium metal under some assumptions. The result showed that it would take a long time to convert the nuclear materials from the FBR fuel cycles without plutonium separation. While it is a preliminary attempt to evaluate a technical factor of proliferation resistance as the basis of the institutional proliferation resistance, the JNC hopes that it will contribute to future discussions in this area. (author)

Material accountancy for metallic fuel pin casting

International Nuclear Information System (INIS)

Bucher, R.G.; Orechwa, Y.; Beitel, J.C.

1995-01-01

The operation of the Fuel Conditioning Facility (FCF) is based on the electrometallurgical processing of spent metallic reactor fuel. The pin casting operation, although only one of several operations in FCF, was the first to be on-line. As such, it has served to demonstrate the material accountancy system in many of its facets. This paper details, for the operation of the pin casting process with depleted uranium, the interaction between the mass tracking system (MTG) and some of the ancillary computer codes which generate pertinent information for operations and material accountancy. It is necessary to distinguish between two types of material balance calculations -- closeout for operations and material accountancy for safeguards. The two have much in common, for example, the mass tracking system database and the calculation of an inventory difference, but, in general, are not congruent with regard to balance period and balance spatial domain. Moreover, the objective, assessment, and reporting requirements of the calculated inventory difference are very different in the two cases

Analysis of material flow in metal forming processes by using computer simulation and experiment with model material

International Nuclear Information System (INIS)

Kim, Heon Young; Kim, Dong Won

1993-01-01

The objective of the present study is to analyze material flow in the metal forming processes by using computer simulation and experiment with model material, plasticine. A UBET program is developed to analyze the bulk flow behaviour of various metal forming problems. The elemental strain-hardening effect is considered in an incremental manner and the element system is automatically regenerated at every deforming step in the program. The material flow behaviour in closed-die forging process with rib-web type cavity are analyzed by UBET and elastic-plastic finite element method, and verified by experiments with plasticine. There were good agreements between simulation and experiment. The effect of corner rounding on material flow behavior is investigated in the analysis of backward extrusion with square die. Flat punch indentation process is simulated by UBET, and the results are compared with that of elastic-plastic finite element method. (Author)

Strain Rate Dependant Material Model for Orthotropic Metals

International Nuclear Information System (INIS)

Vignjevic, Rade

2016-01-01

In manufacturing processes anisotropic metals are often exposed to the loading with high strain rates in the range from 10"2 s"-"1 to 10"6 s"-"1 (e.g. stamping, cold spraying and explosive forming). These types of loading often involve generation and propagation of shock waves within the material. The material behaviour under such a complex loading needs to be accurately modelled, in order to optimise the manufacturing process and achieve appropriate properties of the manufactured component. The presented research is related to development and validation of a thermodynamically consistent physically based constitutive model for metals under high rate loading. The model is capable of modelling damage, failure and formation and propagation of shock waves in anisotropic metals. The model has two main parts: the strength part which defines the material response to shear deformation and an equation of state (EOS) which defines the material response to isotropic volumetric deformation [1]. The constitutive model was implemented into the transient nonlinear finite element code DYNA3D [2] and our in house SPH code. Limited model validation was performed by simulating a number of high velocity material characterisation and validation impact tests. The new damage model was developed in the framework of configurational continuum mechanics and irreversible thermodynamics with internal state variables. The use of the multiplicative decomposition of deformation gradient makes the model applicable to arbitrary plastic and damage deformations. To account for the physical mechanisms of failure, the concept of thermally activated damage initially proposed by Tuller and Bucher [3], Klepaczko [4] was adopted as the basis for the new damage evolution model. This makes the proposed damage/failure model compatible with the Mechanical Threshold Strength (MTS) model Follansbee and Kocks [5], 1988; Chen and Gray [6] which was used to control evolution of flow stress during plastic

Probing the Complexities of Structural Changes in Layered Oxide Cathode Materials for Li-Ion Batteries during Fast Charge-Discharge Cycling and Heating.

Science.gov (United States)

Hu, Enyuan; Wang, Xuelong; Yu, Xiqian; Yang, Xiao-Qing

2018-02-20

this Account, we focus on the recent works studying kinetic and thermal properties of layer-structured cathode materials, especially the structural changes during high rate cycling and the thermal stability during heating. Advanced characterization techniques relating to the rate capability and thermal stability will be introduced. The different structure evolution behavior of cathode materials cycled at high rate will be compared with that cycled at low rate. Different response of individual transition metals and the inhomogeneity in chemical distribution will be discussed. For the thermal stability, the relationship between structural changes and oxygen release will be emphatically pointed out. In all these studies being reviewed, advanced characterization techniques are critically applied to reveal complexities at multiscale in layer-structured cathode materials.

Preparation of Carbon-Encapsulated ZnO Tetrahedron as an Anode Material for Ultralong Cycle Life Performance Lithium-ion Batteries

International Nuclear Information System (INIS)

Ren, Zhimin; Wang, Zhiyu; Chen, Chao; Wang, Jia; Fu, Xinxin; Fan, Chenyao; Qian, Guodong

2014-01-01

Highlights: • A novel architecture of 3D carbon framework to encapsulate ZnO nanocrystals was prepared. • The ZnO@C exhibits ultralong cycle life and high specific capacity when was used as anode. • The in situ carbonization leads to a strong connection between the carbon and ZnO. - ABSTRACT: In this paper we report a novel architecture of three-dimension (3D) carbon framework to encapsulate tetrahedron ZnO nanocrystals that serves as an anode material for lithium-ion batteries (LIBs). The ZnO@C composites are prepared via a simple internal-reflux method combined with subsequent calcination in argon. The amorphous carbon is formed on the surface of the ZnO crystals by in situ carbonization of the surfactant, which leads to a strong connection between the carbon framework and the active materials and guarantees faster charge transfer on the electrode. The ZnO crystal calcined at 500°C (ZnO@C-5) possesses regular tetrahedron shape with a side length of 150-200 nm and all of them are uniformly anchored among the network of amorphous carbon. The developed ZnO@C structures not only improve the electronic conductivity of the electrode, but they also offer a larger volume expansion of ZnO during cycling. As a result, the ZnO@C-5 demonstrates a higher reversible capacity, ultralong cycle life and better rate capability than that of the ZnO@C-7 and pure ZnO crystals. After 300 cycles, the ZnO@C-5 demonstrates a high capacity of 518 mAhg −1 at a current density of 110.7 mAg −1 . Moreover, this simple approach prepared the 3D composites architecture could shed light on the design and synthesis of other transition metal oxides for energy storage

Modelling of the high temperature behaviour of metallic materials

International Nuclear Information System (INIS)

Mohr, R.

1999-01-01

The design of components of metallic high-temperature materials by the finite element method requires the application of phenomenological viscoplastic material models. The route from the choice of a convenient model, the numerical integration of the equations and the parameter identification to the design of components is described. The Chaboche-model is used whose evolution equations are explicitly integrated. The parameters are determined by graphical and numerical methods in order to use the material model for describing the deformation behaviour of a chromium steel and an intermetallic titanium aluminide alloy. (orig.)

Fundamentals of radiation materials science metals and alloys

CERN Document Server

Was, Gary S

2017-01-01

The revised second edition of this established text offers readers a significantly expanded introduction to the effects of radiation on metals and alloys. It describes the various processes that occur when energetic particles strike a solid, inducing changes to the physical and mechanical properties of the material. Specifically it covers particle interaction with the metals and alloys used in nuclear reactor cores and hence subject to intense radiation fields. It describes the basics of particle-atom interaction for a range of particle types, the amount and spatial extent of the resulting radiation damage, the physical effects of irradiation and the changes in mechanical behavior of irradiated metals and alloys. Updated throughout, some major enhancements for the new edition include improved treatment of low- and intermediate-energy elastic collisions and stopping power, expanded sections on molecular dynamics and kinetic Monte Carlo methodologies describing collision cascade evolution, new treatment of t...

On metallic gratings coated conformally with isotropic negative-phase-velocity materials

International Nuclear Information System (INIS)

Inchaussandague, Marina E.; Lakhtakia, Akhlesh; Depine, Ricardo A.

2008-01-01

Application of the differential method (also called the C method) to plane-wave diffraction by a perfectly conducting, sinusoidally corrugated metallic grating coated with a linear, homogeneous, isotropic, lossless dielectric-magnetic material shows that coating materials with negative index of refraction may deliver enhanced maximum nonspecular reflection efficiencies in comparison to coating materials with positive index of refraction

On metallic gratings coated conformally with isotropic negative-phase-velocity materials

Energy Technology Data Exchange (ETDEWEB)

Inchaussandague, Marina E. [GEA-Grupo de Electromagnetismo Aplicado, Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellon I, 1428 Buenos Aires (Argentina); CONICET-Consejo Nacional de Investigaciones Cientificas y Tecnicas, Rivadavia 1917, Buenos Aires (Argentina)], E-mail: mei@df.uba.ar; Lakhtakia, Akhlesh [CATMAS-Computational and Theoretical Materials Sciences Group, Department of Engineering Science and Mechanics, Pennsylvania State University, University Park, PA 16802-6812 (United States)], E-mail: akhlesh@psu.edu; Depine, Ricardo A. [GEA-Grupo de Electromagnetismo Aplicado, Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellon I, 1428 Buenos Aires (Argentina); CONICET-Consejo Nacional de Investigaciones Cientificas y Tecnicas, Rivadavia 1917, Buenos Aires (Argentina)], E-mail: rdep@df.uba.ar

2008-03-31

Application of the differential method (also called the C method) to plane-wave diffraction by a perfectly conducting, sinusoidally corrugated metallic grating coated with a linear, homogeneous, isotropic, lossless dielectric-magnetic material shows that coating materials with negative index of refraction may deliver enhanced maximum nonspecular reflection efficiencies in comparison to coating materials with positive index of refraction.

Semiconductor Metal-Organic Frameworks: Future Low-Bandgap Materials.

Science.gov (United States)

Usman, Muhammad; Mendiratta, Shruti; Lu, Kuang-Lieh

2017-02-01

Metal-organic frameworks (MOFs) with low density, high porosity, and easy tunability of functionality and structural properties, represent potential candidates for use as semiconductor materials. The rapid development of the semiconductor industry and the continuous miniaturization of feature sizes of integrated circuits toward the nanometer (nm) scale require novel semiconductor materials instead of traditional materials like silicon, germanium, and gallium arsenide etc. MOFs with advantageous properties of both the inorganic and the organic components promise to serve as the next generation of semiconductor materials for the microelectronics industry with the potential to be extremely stable, cheap, and mechanically flexible. Here, a perspective of recent research is provided, regarding the semiconducting properties of MOFs, bandgap studies, and their potential in microelectronic devices. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Systems and Methods for Fabricating Structures Including Metallic Glass-Based Materials Using Low Pressure Casting

Science.gov (United States)

Hofmann, Douglas C. (Inventor); Kennett, Andrew (Inventor)

2018-01-01

Systems and methods to fabricate objects including metallic glass-based materials using low-pressure casting techniques are described. In one embodiment, a method of fabricating an object that includes a metallic glass-based material includes: introducing molten alloy into a mold cavity defined by a mold using a low enough pressure such that the molten alloy does not conform to features of the mold cavity that are smaller than 100 microns; and cooling the molten alloy such that it solidifies, the solid including a metallic glass-based material.

Biomolecules for Removal of Heavy Metal.

Science.gov (United States)

Singh, Namita Ashish

2017-01-01

Patents reveal that heavy metals are natural constituents of the earth's crust, but some heavy metals like cadmium, lead, mercury, arsenic etc. are injurious to living organisms at higher concentration. Nowadays, anthropogenic activities have altered geochemical cycles and biochemical balance of heavy metals. Biomolecules are used nowadays for removal of heavy metals compared to other synthetic biosorbents due to their environmental friendly nature and cost effectiveness. The goal of this work is to identify the role of biomolecules like polysaccharides, polypeptides, natural compounds containing aromatic acid etc. for heavy metal removal by bio sorption. It has been observed that efficiency of biomolecules can be increased by functionalization e.g. cellulose functionalization with EDTA, chitosan with sulphur groups, alginate with carboxyl/ hydroxyl group etc. It was found that the porous structure of aerogel beads improves both sorption and kinetic properties of the material. Out of polypeptides metallothionein has been widely used for removal of heavy metal up to 88% from seawater after a single centrifugation. These cost effective functionalized biomolecules are significantly used for remediation of heavy metals by immobilizing these biomolecules onto materials. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Compositions of graphene materials with metal nanostructures and microstructures and methods of making and using including pressure sensors

KAUST Repository

Chen, Ye

2017-01-26

Composition comprising at least one graphene material and at least one metal. The metal can be in the form of nanoparticles as well as microflakes, including single crystal microflakes. The metal can be intercalated in the graphene sheets. The composition has high conductivity and flexibility. The composition can be made by a one-pot synthesis in which a graphene material precursor is converted to the graphene material, and the metal precursor is converted to the metal. A reducing solvent or dispersant such as NMP can be used. Devices made from the composition include a pressure sensor which has high sensitivity. Two two- dimension materials can be combined to form a hybrid material.

Development of materials resistant to metal dusting degradation.

Energy Technology Data Exchange (ETDEWEB)

Natesan, K.; Zeng, Z.

2006-04-24

Metal dusting corrosion has been a serious problem in the petroleum and petrochemical industries, such as reforming and syngas production systems. This form of deterioration has led to worldwide material loss for 50 years. For the past three years, we have studied the mechanism of metal dusting for Fe- and Ni-base alloys. In this report, we present a correlation between the weight loss and depth of pits that form in Ni-base alloys. Nickel-base alloys were also tested at 1 and 14.8 atm (210 psi), in a high carbon activity environment. Higher system pressure was found to accelerate corrosion in most Ni-base alloys. To reduce testing time, a pre-pitting method was developed. Mechanical scratches on the alloy surface led to fast metal dusting corrosion. We have also developed preliminary data on the performance of weldments of several Ni-base alloys in a metal dusting environment. Finally, Alloy 800 tubes and plates used in a reformer plant were examined by scanning electron microscopy, energy dispersive X-ray, and Raman spectroscopy. The oxide scale on the surface of the Alloy 800 primarily consists of Fe{sub 1+x}Cr{sub 2-X}O{sub 4} spinel phase with high Fe content. Carbon can diffuse through this oxide scale. It was discovered that the growth of metal dusting pits could be stopped by means of a slightly oxidized alloy surface. This leads to a new way to solve metal dusting problem.

Contribution of nuclear analysis methods to the certification of BCR reference materials for non-metals in non-ferrous metals

International Nuclear Information System (INIS)

Pauwels, J.

1979-01-01

A number of reference materials for oxygen in different non-ferrous metals have been certified by BCR in the frame of a multidisciplinary Community project. The contribution of nuclear analysis methods is illustrated by several examples concerning the optimization of sample preparation techniques, the analysis of low and high oxygen non-ferrous metals and the extension of the program to other non-metals, especially nitrogen and carbon. (author)

Status quo of ceramic material for metal halide discharge lamps

International Nuclear Information System (INIS)

Kappen, Theo G M M

2005-01-01

Polycrystalline alumina is an excellent ceramic material for use as the envelope for metal halide discharge lamps. Although this material was introduced in the mid-1960s, and is thus already known for several decades, recent years have seen considerable effort aimed at further development of these ceramic envelope materials. Developments are not only in the field of ceramic shaping technologies, but are also concentrated on the material properties of the ceramic material itself. Optical, mechanical as well as the chemical properties of the ceramic envelope are strongly controlled by the shape as well as the microstructure of the ceramics used

Critical factors affecting life cycle assessments of material choice for vehicle mass reduction

Science.gov (United States)

This review examines the use of life-cycle assessments (LCAs) to compare different lightweight materials being developed to improve light-duty vehicle fuel economy. Vehicle manufacturers are designing passenger cars and light-duty trucks using lighter weight materials and design ...

Utilising the emergency planning cycle for the transport of radioactive material

International Nuclear Information System (INIS)

Fox, M.

2004-01-01

As a world leader in the transport of radioactive material (RAM) British Nuclear Fuels plc (BNFL) and its subsidiary Pacific Nuclear Transport Limited (PNTL) recognise the importance of adopting the emergency planning cycle. The emergency response arrangements prepared and maintained in support of the International Transport business have been developed through this cycle to ensure that their emergency response section may achieve its aim and that the business unit is able to respond to any International Transport related incident in a swift, combined and co-ordinated manner. This paper outlines the eight key stages of the planning cycle and the experience that BNFL has gained in respect of its emergency response activities

The Spanish Protocol for Collaboration on the Radiological Surveillance of Metallic Materials

Energy Technology Data Exchange (ETDEWEB)

Redondo, J.M., E-mail: jmredondo@mityc.es [Ministry of Industry, Tourism and Trade (Spain)

2011-07-15

In recent years the presence of radioactive material in scrap metal has been detected relatively often. This can cause the contamination of people or of the environment, as well as of the industrial facilities and of the product. The Spanish iron and steel industry is one of the most important industrial sectors in the country, and depends to a large extent on the importation of a significant proportion of the scrap used as raw material. Experience has shown that countries that import large quantities of scrap for their industries are more exposed to the existence of orphan radioactive sources and therefore, they have to adopt measures to reduce the risks arising from their presence. In 1999, the Spanish authorities, along with the business associations involved in the metal recovery and smelting industry, and the radioactive waste management agency, established a national system for the radiological surveillance and control of scrap metal and the products resulting from its processing. Since then, the most relevant trade unions and others in the industrial sector have also joined the system. It is based on the existence of a legal framework and on a set of voluntary commitments taken on by the involved parties. It is known as the Protocol for Collaboration for the Radiological Surveillance of Metallic Materials and is implemented by the installation of specific radiological surveillance equipment, the development of radiological training and information plans for the staff involved in the metal recovery and smelting sectors, the definition of a fully operational system to safely manage the materials detected, and a general improvement of the national radiological emergency system. (author)

The Process of Nanostructuring of Metal (Iron Matrix in Composite Materials for Directional Control of the Mechanical Properties

Directory of Open Access Journals (Sweden)

Elena Zemtsova

2014-01-01

Full Text Available We justified theoretical and experimental bases of synthesis of new class of highly nanostructured composite nanomaterials based on metal matrix with titanium carbide nanowires as dispersed phase. A new combined method for obtaining of metal iron-based composite materials comprising the powder metallurgy processes and the surface design of the dispersed phase is considered. The following stages of material synthesis are investigated: (1 preparation of porous metal matrix; (2 surface structuring of the porous metal matrix by TiC nanowires; (3 pressing and sintering to give solid metal composite nanostructured materials based on iron with TiC nanostructures with size 1–50 nm. This material can be represented as the material type “frame in the frame” that represents iron metal frame reinforcing the frame of different chemical compositions based on TiC. Study of material functional properties showed that the mechanical properties of composite materials based on iron with TiC dispersed phase despite the presence of residual porosity are comparable to the properties of the best grades of steel containing expensive dopants and obtained by molding. This will solve the problem of developing a new generation of nanostructured metal (iron-based materials with improved mechanical properties for the different areas of technology.

Analytical methods for fissionable materials in the nuclear fuel cycle. Covering June 1974--June 1975

International Nuclear Information System (INIS)

Waterbury, G.R.

1975-10-01

Research progress is reported on method development for the dissolution of difficult-to-dissolve materials, the automated analysis of plutonium and uranium, the preparation of plutonium materials for the Safeguard Analytical Laboratory Evaluation (SALE) Program, and the analysis of HTGR fuel and SALE uranium materials. The previously developed Teflon-container, metal-shell apparatus was applied to the dissolution of various nuclear materials. Gas--solid reactions, mainly using chlorine at elevated temperatures, are promising for separating uranium from refractory compounds. An automated spectrophotometer designed for determining plutonium and uranium was tested successfully. Procedures were developed for this instrument to analyze uranium--plutonium mixtures and the effects of diverse ions upon the analysis of plutonium and uranium were further established. A versatile apparatus was assembled to develop electrotitrimetric methods that will serve as the basis for precise automated determinations of plutonium. Plutonium materials prepared for the Safeguard Analytical Laboratory Evaluation (SALE) Program were plutonium oxide, uranium--plutonium mixed oxide, and plutonium metal. Improvements were made in the methods used for determining uranium in HTGR fuel materials and SALE uranium materials. Plutonium metal samples were prepared, characterized, and distributed, and half-life measurements were in progress as part of an inter-ERDA-laboratory program to measure accurately the half-lives of long-lived plutonium isotopes

Recycling of Metals and Materials: A Selected Bibliography.

Science.gov (United States)

Seidman, Ruth K., Comp.; Castrow, Lee, Comp.

Recycling of metals and materials has as its purpose the easing of two major environmental crises. First, we re-utilize scarce and non-renewable resources. Second, solid waste disposal problems can be alleviated. Industry has long been concerned with reclaiming its own waste products, and is now beginning to respond to the need for dealing with…

Isotopic evidence for primordial molecular cloud material in metal-rich carbonaceous chondrites

DEFF Research Database (Denmark)

van Kooten, Elishevah M. M. E.; Wielandt, Daniel Kim Peel; Schiller, Martin

2016-01-01

product of (26)Al. This correlation is interpreted as reflecting progressive thermal processing of in-falling (26)Al-rich molecular cloud material in the inner Solar System. The thermally unprocessed molecular cloud matter reflecting the nucleosynthetic makeup of the molecular cloud before the last......)Mg*-depleted and (54)Cr-enriched component. This composition is consistent with that expected for thermally unprocessed primordial molecular cloud material before its pollution by stellar-derived (26)Al. The (26)Mg* and (54)Cr compositions of bulk metal-rich chondrites require significant amounts (25......-50%) of primordial molecular cloud matter in their precursor material. Given that such high fractions of primordial molecular cloud material are expected to survive only in the outer Solar System, we infer that, similarly to cometary bodies, metal-rich carbonaceous chondrites are samples of planetesimals...

Laser-shocked energetic materials with metal additives: evaluation of detonation performance

Science.gov (United States)

Gottfried, Jennifer; Bukowski, Eric

A focused, nanosecond-pulsed laser with sufficient energy to exceed the breakdown threshold of a material generates a laser-induced plasma with high peak temperatures, pressures, and shock velocities. Depending on the laser parameters and material properties, nanograms to micrograms of material is ablated, atomized, ionized and excited in the laser-induced plasma. The subsequent shock wave expansion into the air above the sample has been monitored using high-speed schlieren imaging in a recently developed technique, laser-induced air shock from energetic materials (LASEM). The estimated detonation velocities using LASEM agree well with published experimental values. A comparison of the measured shock velocities for various energetic materials including RDX, DNTF, and LLM-172 doped with Al or B to the detonation velocities predicted by CHEETAH for inert or active metal participation demonstrates that LASEM has potential for predicting the early time participation of metal additives in detonation events. The LASEM results show that reducing the amount of hydrogen present in B formulations increases the resulting detonation velocities

ANDRA - Referential Materials. Volume 1: Context and scope; Volume 2: Argillaceous materials; Volume 3: Cementitious materials; Volume 4: The corrosion of metallic materials

International Nuclear Information System (INIS)

2001-01-01

This huge document gathers four volumes. The first volume presents some generalities about materials used in the storage of radioactive materials (definition, design principle, current choices and corresponding storage components, general properties of materials and functions of the corresponding storage components, physical and chemical solicitations experienced by materials in a storage), and the structure and content of the other documents. The second volume addresses argillaceous materials. It presents some generalities about these materials in the context of a deep geological storage, and about their design. It presents and comments the crystalline and chemical, and physical and chemical characteristics of swelling argillaceous materials and minerals, describes how these swelling argillaceous materials are shaped and set up, presents and comments physical properties (hydraulic, mechanical and thermal properties) of these materials, comments and discusses the modelling of the geo-chemical behaviour, and their behaviour in terms of containment and transport of radionuclides. The third volume addresses cementitious materials. It presents some generalities about these materials in the context of a deep geological storage, and about their definition and specifications. It presents some more detailed generalities (cement definition and composition, hydration, microstructure of hydrated cements, adjuvants), presents and comments their physical properties (fresh concrete structure and influence of composition, main aimed properties in the hardened status, transfer, mechanical, and thermal properties, shaping and setting up of these materials, technical solutions for hydraulic works). The fourth volume addresses the corrosion of metallic materials. It presents some generalities about these materials in the context of a deep geological storage of radioactive materials. It presents metallic materials and discusses their corrosion behaviour. It describes the peculiarities

Metal phosphonate hybrid mesostructures: environmentally friendly multifunctional materials for clean energy and other applications.

Science.gov (United States)

Ma, Tian-Yi; Yuan, Zhong-Yong

2011-10-17

The synthesis of porous hybrid materials has been extended to mesoporous non-silica-based organic-inorganic hybrid materials, in which mesoporous metal phosphonates represent an important family. By using organically bridged polyphosphonic acids as coupling molecules, the homogeneous incorporation of a considerable number of organic functional groups into the metal phosphonate hybrid framework has been realized. Small amounts of organic additives and the pH value of the reaction solution have a large impact on the morphology and textural properties of the resultant hybrid mesoporous metal phosphonate solids. Cationic and nonionic surfactants can be used as templates for the synthesis of ordered mesoporous metal phosphonates. The materials are used as efficient adsorbents for heavy metal ions, CO₂, and aldehydes, as well as in the separation of polycyclic aromatic hydrocarbons. They are also useful photocatalysts under UV and simulated solar light irradiation for organic dye degradation. Further functionalization of the synthesized mesoporous hybrids makes them oxidation and acid catalysts, both with impressive performances in the fields of sustainable energy and environment. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

STATISTICAL DISTRIBUTION PATTERNS IN MECHANICAL AND FATIGUE PROPERTIES OF METALLIC MATERIALS

OpenAIRE

Tatsuo, SAKAI; Masaki, NAKAJIMA; Keiro, TOKAJI; Norihiko, HASEGAWA; Department of Mechanical Engineering, Ritsumeikan University; Department of Mechanical Engineering, Toyota College of Technology; Department of Mechanical Engineering, Gifu University; Department of Mechanical Engineering, Gifu University

1997-01-01

Many papers on the statistical aspect of materials strength have been collected and reviewed by The Research Group for Statistical Aspects of Materials Strength.A book of "Statistical Aspects of Materials Strength" was written by this group, and published in 1992.Based on the experimental data compiled in this book, distribution patterns of mechanical properties are systematically surveyed paying an attention to metallic materials.Thus one can obtain the fundamental knowledge for a reliabilit...

A metallization and bonding approach for high performance carbon nanotube thermal interface materials

International Nuclear Information System (INIS)

Cross, Robert; Graham, Samuel; Cola, Baratunde A; Fisher, Timothy; Xu Xianfan; Gall, Ken

2010-01-01

A method has been developed to create vertically aligned carbon nanotube (VACNT) thermal interface materials that can be attached to a variety of metallized surfaces. VACNT films were grown on Si substrates using standard CVD processing followed by metallization using Ti/Au. The coated CNTs were then bonded to metallized substrates at 220 deg. C. By reducing the adhesion of the VACNTs to the growth substrate during synthesis, the CNTs can be completely transferred from the Si growth substrate and used as a die attachment material for electronic components. Thermal resistance measurements using a photoacoustic technique showed thermal resistances as low as 1.7 mm 2 K W -1 for bonded VACNT films 25-30 μm in length and 10 mm 2 K W -1 for CNTs up to 130 μm in length. Tensile testing demonstrated a die attachment strength of 40 N cm -2 at room temperature. Overall, these metallized and bonded VACNT films demonstrate properties which are promising for next-generation thermal interface material applications.

Real-time materials evolution visualized within intact cycling alkaline batteries

Energy Technology Data Exchange (ETDEWEB)

Gallaway, JW; Erdonmez, CK; Zhong, Z; Croft, M; Sviridov, LA; Sholklapper, TZ; Turney, DE; Banerjee, S; Steingart, DA

2014-01-01

The scientific community has focused on the problem of inexpensive, safe, and sustainable large-scale electrical energy storage, which is needed for a number of emerging societal reasons such as stabilizing intermittent renewables-based generation like solar and wind power. The materials used for large-scale storage will need to be low cost, earth-abundant, and safe at the desired scale. The Zn-MnO2 "alkaline" battery chemistry is associated with one-time use, despite being rechargeable. This is due to material irreversibilities that can be triggered in either the anode or cathode. However, as Zn and MnO2 have high energy density and low cost, they are economically attractive even at limited depth of discharge. As received, a standard bobbin-type alkaline cell costs roughly $20 per kW h. The U. S. Department of Energy ARPA-E $100 per kW h cost target for grid storage is thus close to the cost of alkaline consumer primary cells if re-engineered and/or cycled at 5-20% nominal capacity. Herein we use a deeply-penetrating in situ technique to observe ZnO precipitation near the separator in an alkaline cell anode cycled at 5% DOD, which is consistent with cell failures observed at high cycle life. Alkaline cells designed to avoid such causes of cell failure could serve as a low-cost baseload for large-scale storage.

Enhancement of the lithium cycling capability using Li–Zn alloy substrate for lithium metal batteries

International Nuclear Information System (INIS)

Chen, Chen; Yang, Yifu; Shao, Huixia

2014-01-01

Graphical abstract: - Highlights: • Li-Zn alloy substrate is novelly formed by Li electrodeposition on the Zn substrate precursor. • The coulombic efficiency of Li deposition/stripping on the Li-Zn alloy substrate remains high at 96.7% after 400 cycles. • The SEI film formed during the formation of Li-Zn alloy is stable during Li deposition/stripping cycling on the Li-Zn substrate. • The exchange current density of Li deposition on the Li-Zn substrate is 9.21 × 10 −4 A cm −2 which is nearly eight times larger than that on the Cu substrate. - Abstract: The cycling performance of a Li metal electrode in rechargeable Li batteries is studied using a novelly formed Li–Zn alloy as a substrate. A Zn layer electrodeposited on a Cu disk with ultrasonic assistance is used as a substrate precursor. Li electrodeposition followed to form the Li–Zn alloy. The morphologies of the substrate before and after Li deposition and stripping are investigated by scanning electron microscopy (SEM), and the electrochemical properties of the substrate are investigated by galvanostatic charge-discharge and cyclic voltammetry (CV). The growth states of solid electrolyte interface (SEI) films of Li deposits on the Li–Zn alloy and Cu surfaces are compared by electrochemical impedance spectroscopy (EIS); exchange current densities of Li electrodeposition on Cu, Zn, and Li–Zn alloy substrates are also compared based on tests of constant current pulse deposition. The efficiency of Li deposition/stripping on the Li–Zn alloy substrate remains high at 96.7% after 400 cycles at a current density of 0.1 mA cm −2 and 250 cycles at the current density of 0.2 mA cm −2 . These results can be attributed to the formation of a stable SEI film on the Li–Zn substrate and the high exchange current density of Li deposition and stripping on this substrate. The Li–Zn alloy proposed in this work may be a perfect substrate for enhancing the cycling capability of Li metal electrode

Comparison of filter media materials for heavy metal removal from urban stormwater runoff using biofiltration systems.

Science.gov (United States)

Lim, H S; Lim, W; Hu, J Y; Ziegler, A; Ong, S L

2015-01-01

The filter media in biofiltration systems play an important role in removing potentially harmful pollutants from urban stormwater runoff. This study compares the heavy metal removal potential (Cu, Zn, Cd, Pb) of five materials (potting soil, compost, coconut coir, sludge and a commercial mix) using laboratory columns. Total/dissolved organic carbon (TOC/DOC) was also analysed because some of the test materials had high carbon content which affects heavy metal uptake/release. Potting soil and the commercial mix offered the best metal uptake when dosed with low (Cu: 44.78 μg/L, Zn: 436.4 μg/L, Cd, 1.82 μg/L, Pb: 51.32 μg/L) and high concentrations of heavy metals (Cu: 241 μg/L, Zn: 1127 μg/L, Cd: 4.57 μg/L, Pb: 90.25 μg/L). Compost and sludge also had high removal efficiencies (>90%). Heavy metal leaching from these materials was negligible. A one-month dry period between dosing experiments did not affect metal removal efficiencies. TOC concentrations from all materials increased after the dry period. Heavy metal removal was not affected by filter media depth (600 mm vs. 300 mm). Heavy metals tended to accumulate at the upper 5 cm of the filter media although potting soil showed bottom-enriched concentrations. We recommend using potting soil as the principal media mixed with compost or sludge since these materials perform well and are readily available. The use of renewable materials commonly found in Singapore supports a sustainable approach to urban water management. Copyright © 2014 Elsevier Ltd. All rights reserved.

Control and Management of Radioactive Material Inadvertently Incorporated into Scrap Metal. Proceedings of an International Conference

International Nuclear Information System (INIS)

2011-01-01

Radioactive substances can become associated with scrap metal in various ways and if not discovered they can be incorporated into steel and non-ferrous metals through the melting process. This can cause health hazards as well as environmental concerns and there can be serious commercial implications. Numerous incidents have occurred in recent years involving the discovery of radioactive substances in scrap metal and, in some cases, in metal from the melting process. These incidents have proved to be very costly in relation to the recovery and cleanup operations required but also in terms of the potential loss of confidence of the industry in scrap metal as a resource. This has led the scrap metal industry to seek ways of managing the problem. In most countries, shipments of scrap metal are monitored but at different points in the distribution chain and to different extents and efficiencies. As yet, only limited efforts towards unifying and harmonizing monitoring strategies and methods in the context of scrap metal have been made at the international level. The Conference was organized into five sessions: the global perspective, national policies and strategies, compliance with radiological criteria, management of incidents with contaminated scrap metal, and improving confidence and protecting the interests of stakeholders. The aim of the first session was to present the views and perspectives of the different organizations concerned with radioactive material in scrap metal, scrap metal recycling, steel making, radiation source security and safety and international trade and economics. The second session covered some of the national policies and strategies being used to address the control of radioactive material that has been inadvertently incorporated into scrap metal were presented. In addition to the oral presentations, contributions describing the situation in many countries of the world in the form of posters were displayed. The many posters reporting national

Control and Management of Radioactive Material Inadvertently Incorporated into Scrap Metal. Proceedings of an International Conference

Energy Technology Data Exchange (ETDEWEB)

NONE

2011-07-15

Radioactive substances can become associated with scrap metal in various ways and if not discovered they can be incorporated into steel and non-ferrous metals through the melting process. This can cause health hazards as well as environmental concerns and there can be serious commercial implications. Numerous incidents have occurred in recent years involving the discovery of radioactive substances in scrap metal and, in some cases, in metal from the melting process. These incidents have proved to be very costly in relation to the recovery and cleanup operations required but also in terms of the potential loss of confidence of the industry in scrap metal as a resource. This has led the scrap metal industry to seek ways of managing the problem. In most countries, shipments of scrap metal are monitored but at different points in the distribution chain and to different extents and efficiencies. As yet, only limited efforts towards unifying and harmonizing monitoring strategies and methods in the context of scrap metal have been made at the international level. The Conference was organized into five sessions: the global perspective, national policies and strategies, compliance with radiological criteria, management of incidents with contaminated scrap metal, and improving confidence and protecting the interests of stakeholders. The aim of the first session was to present the views and perspectives of the different organizations concerned with radioactive material in scrap metal, scrap metal recycling, steel making, radiation source security and safety and international trade and economics. The second session covered some of the national policies and strategies being used to address the control of radioactive material that has been inadvertently incorporated into scrap metal were presented. In addition to the oral presentations, contributions describing the situation in many countries of the world in the form of posters were displayed. The many posters reporting national

Inkjet printing metals on flexible materials for plastic and paper electronics

DEFF Research Database (Denmark)

Al-Shamery, K.; Raut, N. C.

2018-01-01

Inorganic printed electronics is now recognized as an area of tremendous commercial, potential and technical progress. Many research groups are actively involved worldwide in developing metal nanoparticle inks and precursors for printing inorganic/organic materials using different printing....... Besides some examples demonstrating aspects on ink formulation via patterning solid surfaces such as glass and silicon oxide, special emphasis will be placed on compatibility for usage in plastic and paper electronics. Printing of nanoparticles of copper, silver, gold etc. will be discussed...... and will be compared to printing of a variety of metal-organic precursor inks. Finally, a brief account on exemplary applications using the printed inorganic nanoparticles/materials is provided....

Metal sulfide electrodes and energy storage devices thereof

Science.gov (United States)

Chiang, Yet-Ming; Woodford, William Henry; Li, Zheng; Carter, W. Craig

2017-02-28

The present invention generally relates to energy storage devices, and to metal sulfide energy storage devices in particular. Some aspects of the invention relate to energy storage devices comprising at least one flowable electrode, wherein the flowable electrode comprises an electroactive metal sulfide material suspended and/or dissolved in a carrier fluid. In some embodiments, the flowable electrode further comprises a plurality of electronically conductive particles suspended and/or dissolved in the carrier fluid, wherein the electronically conductive particles form a percolating conductive network. An energy storage device comprising a flowable electrode comprising a metal sulfide electroactive material and a percolating conductive network may advantageously exhibit, upon reversible cycling, higher energy densities and specific capacities than conventional energy storage devices.

Metallic materials corrosion problems in molten salt reactors

International Nuclear Information System (INIS)

Chauvin, G.; Dixmier, J.; Jarny, P.

1977-01-01

The USA forecastings concerning the molten salt reactors are reviewed (mixtures of fluorides containing the fuel, operating between 560 and 700 0 C). Corrosion problems are important in these reactors. The effects of certain characteristic factors on corrosion are analyzed: humidity and metallic impurities in the salts, temperature gradients, speed of circulation of salts, tellurium from fission products, coupling. In the molten fluorides and experimental conditions, the materials with high Ni content are particularly corrosion resistant alloys (hastelloy N). The corrosion of this material is about 2.6 mg.cm -2 at 700 0 C [fr

Life cycle assessment of the Danish electricity distribution network

DEFF Research Database (Denmark)

Turconi, Roberto; Simonsen, Christian G.; Byriel, Inger P.

2014-01-01

Purpose This article provides life cycle inventory data for electricity distribution networks and a life cycle assessment (LCA) of the Danish transmission and distribution networks. The aim of the study was to evaluate the potential importance of environmental impacts associated with distribution...... complexity and material consumption. Infrastructure provided important contributions to metal depletion and freshwater eutrophication (copper and aluminum for manufacturing of the cables and associated recycling being the most important). Underground 50-kV lines had larger impacts than overhead lines, and 0...

Multifunctional Metallic and Refractory Materials for Energy Efficient Handling of Molten Metals

Energy Technology Data Exchange (ETDEWEB)

Xingbo Liu; Ever Barbero; Bruce Kang; Bhaskaran Gopalakrishnan; James Headrick; Carl Irwin

2009-02-06

The goal of the project was to extend the lifetime of hardware submerged in molten metal by an order of magnitude and to improve energy efficiency of molten metal handling process. Assuming broad implementation of project results, energy savings in 2020 were projected to be 10 trillion BTU/year, with cost savings of approximately $100 million/year. The project team was comprised of materials research groups from West Virginia University and the Missouri University of Science and Technology formerly University of Missouri – Rolla, Oak Ridge National Laboratory, International Lead and Zinc Research Organization, Secat and Energy Industries of Ohio. Industry partners included six suppliers to the hot dip galvanizing industry, four end-user steel companies with hot-dip Galvanize and/or Galvalume lines, eight refractory suppliers, and seven refractory end-user companies. The results of the project included the development of: (1) New families of materials more resistant to degradation in hot-dip galvanizing bath conditions were developed; (2) Alloy 2020 weld overlay material and process were developed and applied to GI rolls; (3) New Alloys and dross-cleaning procedures were developed for Galvalume processes; (4) Two new refractory compositions, including new anti-wetting agents, were identified for use with liquid aluminum alloys; (5) A new thermal conductivity measurement technique was developed and validated at ORNL; (6) The Galvanizing Energy Profiler Decision Support System (GEPDSS)at WVU; Newly Developed CCW Laser Cladding Shows Better Resistance to Dross Buildup than 316L Stainless Steel; and (7) A novel method of measuring the corrosion behavior of bath hardware materials. Project in-line trials were conducted at Southwire Kentucky Rod and Cable Mill, Nucor-Crawfordsville, Nucor-Arkansas, Nucor-South Carolina, Wheeling Nisshin, California Steel, Energy Industries of Ohio, and Pennex Aluminum. Cost, energy, and environmental benefits resulting from the project

Characterization of liquid metal reactor materials

International Nuclear Information System (INIS)

Kuk, I. H.; Ryu, W. S.; Kim, H. H. and others

1999-03-01

The objectives of this report were to assess the material requirements for LMR environment, to select the optimum candidates for KALIMER components, to characterize the performance for establishing a database of the structural materials for KALIMER, and to develop the basic material technologies for the localization of the advanced materials. Stainless steel ingots were melted by VIM and hot-rolled to plate with the thickness of 15mm. The plate was solution-treated for 1 hr at 1100 deg C and then water-quenched. Specimens were taken parallel to the rolling direction of the plate. The effects of nitrogen and phosphorus were analyzed on the high temperature mechanical properties of 316MRP (Liquid Metal Reactor, Primary candidate material) stainless steels with the different nitrogen content from 0.04 to 0.15% and with the different phosphorus content from 0.002 to 0.02%. Heat treatment was performed to investigate the changes in microstructure and mechanical properties of Cr-Mo steels for LMR heat transfer tube materials and core materials. The Cr-Mo steels were normalized at the temperatures between 900 deg C and 1200 deg C for 1hrs and tempered at the temperatures between 500 deg C and 800 deg C for 2hrs. Conventional optical and electron micrographic studies were carried out to investigate the martensite lath structure, carbide indentification and carbide shape. Vickers microhardness was measured at room temperature using 10g load. Tensile properties were tested at high temperature. Charpy V-notch impact tests were also carried out at temperature between -120 deg C and +180 deg C. (author). 72 refs., 28 tabs., 244 figs

Evaluation of material integrity on electricity power steam generator cycles (turbine casing) component

International Nuclear Information System (INIS)

Histori; Benedicta; Farokhi; S A, Soedardjo; Triyadi, Ari; Natsir, M

1999-01-01

The evaluation of material integrity on power steam generator cycles component was done. The test was carried out on casing turbine which is made from Inconel 617. The tested material was taken from t anjung Priok plant . The evaluation was done by metallography analysis using microscope with magnification of 400. From the result, it is shown that the material grains are equiaxed

Novel strategy for the preparation of graphene-encapsulated mesoporous metal oxides with enhanced lithium storage

International Nuclear Information System (INIS)

Lin, Rong; Yue, Wenbo; Niu, Fangzhou; Ma, Jie

2016-01-01

As potential anode materials for lithium-ion batteries, mesoporous metal oxides show high reversible capacities but relatively poor cycle stability due to the structural collapse during cycles. Graphene-encapsulated mesoporous metal oxides may increase the electronic conductivity of the composite as well as stabilize the mesostructure of metal oxides, thereby enhancing the electrochemical performance of mesoporous metal oxides. Herein we describe a novel strategy for the preparation of graphene-encapsulated mesoporous metal oxides (SnO_2, Mn_3O_4), which exhibit superior electrochemical performance compared to pure mesoporous metal oxides. Moreover, some mesoporous metal oxides may be further reduced to low-valence metal oxides when calcined in presence of graphene. Mesoporous metal oxides with high isoelectric points are not essential for this synthesis method since metal oxides are connected with graphene through mesoporous silica template, thus expanding the types of graphene-encapsulated mesoporous metal oxides.

Research on metallic material defect detection based on bionic sensing of human visual properties

Science.gov (United States)

Zhang, Pei Jiang; Cheng, Tao

2018-05-01

Due to the fact that human visual system can quickly lock the areas of interest in complex natural environment and focus on it, this paper proposes an eye-based visual attention mechanism by simulating human visual imaging features based on human visual attention mechanism Bionic Sensing Visual Inspection Model Method to Detect Defects of Metallic Materials in the Mechanical Field. First of all, according to the biologically visually significant low-level features, the mark of defect experience marking is used as the intermediate feature of simulated visual perception. Afterwards, SVM method was used to train the advanced features of visual defects of metal material. According to the weight of each party, the biometrics detection model of metal material defect, which simulates human visual characteristics, is obtained.

Metal-Free Oxidation of Primary Amines to Nitriles through Coupled Catalytic Cycles.

Science.gov (United States)

Lambert, Kyle M; Bobbitt, James M; Eldirany, Sherif A; Kissane, Liam E; Sheridan, Rose K; Stempel, Zachary D; Sternberg, Francis H; Bailey, William F

2016-04-04

Synergism among several intertwined catalytic cycles allows for selective, room temperature oxidation of primary amines to the corresponding nitriles in 85-98% isolated yield. This metal-free, scalable, operationally simple method employs a catalytic quantity of 4-acetamido-TEMPO (ACT; TEMPO=2,2,6,6-tetramethylpiperidine N-oxide) radical and the inexpensive, environmentally benign triple salt oxone as the terminal oxidant under mild conditions. Simple filtration of the reaction mixture through silica gel affords pure nitrile products. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Hydrogen storage for fuel cell applications: Challenges, opportunities and prospects for metal-organic frameworks

CSIR Research Space (South Africa)

Langmi, Henrietta W

2013-07-01

Full Text Available and release, and cycle life of the materials. In the past decade, there has been growing interest in metal organic frameworks (MOFs) as hydrogen storage materials and significant progress has been made in this regard. The challenges, opportunities...

Composite metal-hydrogen electrodes for metal-hydrogen batteries. Final report, October 1, 1993 - April 15, 1997

International Nuclear Information System (INIS)

Ruckman, M.W.; Strongin, M.; Weismann, H.

1997-04-01

The purpose of this project is to develop and conduct a feasibility study of metallic thin films (multilayered and alloy composition) produced by advanced sputtering techniques for use as anodes in Ni-metal hydrogen batteries that would be deposited as distinct anode, electrolyte and cathode layers in thin film devices. The materials could also be incorporated in secondary consumer batteries (i.e. type AF(4/3 or 4/5)) which use electrodes in the form of tapes. The project was based on pioneering studies of hydrogen uptake by ultra-thin Pd-capped Nb films, these studies suggested that materials with metal-hydrogen ratios exceeding those of commercially available metal hydride materials and fast hydrogen charging and discharging kinetics could be produced. The project initially concentrated on gas phase and electrochemical studies of Pd-capped niobium films in laboratory-scale NiMH cells. This extended the pioneering work to the wet electrochemical environment of NiMH batteries and exploited advanced synchrotron radiation techniques not available during the earlier work to conduct in-situ studies of such materials during hydrogen charging and discharging. Although batteries with fast charging kinetics and hydrogen-metal ratios approaching unity could be fabricated, it was found that oxidation, cracking and corrosion in aqueous solutions made pure Nb films and multilayers poor candidates for battery application. The project emphasis shifted to alloy films based on known elemental materials used for NiMH batteries. Although commercial NiMH anode materials contain many metals, it was found that 0.24 μm thick sputtered Zr-Ni films cycled at least 50 times with charging efficiencies exceeding 95% and [H]/[M] ratios of 0.7-1.0. Multilayered or thicker Zr-Ni films could be candidates for a thin film NiMH battery that may have practical applications as an integrated power source for modern electronic devices

Biogeochemical Cycling of Nutrients and Trace Metals in the Sediment of Haringvliet Lake: Response to Salinization

NARCIS (Netherlands)

Canavan, R.W.

2006-01-01

This thesis examines sediment redox processes associated with organic matter degradation and their impact on the cycling of nutrients (N, P) and trace metals (Cd, Co, Ni, Pb, Zn). Our study site, Haringvliet Lake, is located in the Rhine-Meuse River Delta in the southwest of The Netherlands. This

Metal-nanotube composites as radiation resistant materials

Energy Technology Data Exchange (ETDEWEB)

González, Rafael I.; Valencia, Felipe; Mella, José; Kiwi, Miguel, E-mail: m.kiwi.t@gmail.com [Departamento de Física, Facultad de Ciencias, CEDENNA, Universidad de Chile, Casilla 653, Santiago 7800024 (Chile); Duin, Adri C. T. van [Department of Mechanical and Nuclear Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States); So, Kang Pyo; Li, Ju [Department of Nuclear Science and Engineering and Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Bringa, Eduardo M. [CONICET and Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Mendoza 5500 (Argentina)

2016-07-18

The improvement of radiation resistance in nanocomposite materials is investigated by means of classical reactive molecular dynamics simulations. In particular, we study the influence of carbon nanotubes (CNTs) in an Ni matrix on the trapping and possible outgassing of He. When CNTs are defect-free, He atoms diffuse alongside CNT walls and, although there is He accumulation at the metal-CNT interface, no He trespassing of the CNT wall is observed, which is consistent with the lack of permeability of a perfect graphene sheet. However, when vacancies are introduced to mimic radiation-induced defects, He atoms penetrate CNTs, which play the role of nano-chimneys, allowing He atoms to escape the damaged zone and reduce bubble formation in the matrix. Consequently, composites made of CNTs inside metals are likely to display improved radiation resistance, particularly when radiation damage is related to swelling and He-induced embrittlement.

Metal-nanotube composites as radiation resistant materials

International Nuclear Information System (INIS)

González, Rafael I.; Valencia, Felipe; Mella, José; Kiwi, Miguel; Duin, Adri C. T. van; So, Kang Pyo; Li, Ju; Bringa, Eduardo M.

2016-01-01

The improvement of radiation resistance in nanocomposite materials is investigated by means of classical reactive molecular dynamics simulations. In particular, we study the influence of carbon nanotubes (CNTs) in an Ni matrix on the trapping and possible outgassing of He. When CNTs are defect-free, He atoms diffuse alongside CNT walls and, although there is He accumulation at the metal-CNT interface, no He trespassing of the CNT wall is observed, which is consistent with the lack of permeability of a perfect graphene sheet. However, when vacancies are introduced to mimic radiation-induced defects, He atoms penetrate CNTs, which play the role of nano-chimneys, allowing He atoms to escape the damaged zone and reduce bubble formation in the matrix. Consequently, composites made of CNTs inside metals are likely to display improved radiation resistance, particularly when radiation damage is related to swelling and He-induced embrittlement.

Assessment of the effects of the Japanese shift to lead-free solders and its impact on material substitution and environmental emissions by a dynamic material flow analysis

International Nuclear Information System (INIS)

Fuse, Masaaki; Tsunemi, Kiyotaka

2012-01-01

Lead-free electronics has been extensively studied, whereas their adoption by society and their impact on material substitution and environmental emissions are not well understood. Through a material flow analysis (MFA), this paper explores the life cycle flows for solder-containing metals in Japan, which leads the world in the shift to lead-free solders in electronics. The results indicate that the shift has been progressing rapidly for a decade, and that substitutes for lead in solders, which include silver and copper, are still in the early life cycle stages. The results also show, however, that such substitution slows down during the late life cycle stages owing to long electronic product lifespans. This deceleration of material substitution in the solder life cycle may not only preclude a reduction in lead emissions to air but also accelerate an increase in silver emissions to air and water. As an effective measure against ongoing lead emissions, our scenario analysis suggests an aggressive recycling program for printed circuit boards that utilizes an existing recycling scheme. -- Highlights: ► We model the life cycle flows for solder-containing metals in Japan. ► The Japanese shift to lead-free solders progresses rapidly for a decade. ► Substitution for lead in solders slows down during the late life cycle stages. ► The deceleration of substitution precludes a reduction in lead emissions to air.

Aplicación de un material vitrocerámico a la biorremediación de metales pesados

Directory of Open Access Journals (Sweden)

García, A. M.

2004-02-01

Full Text Available In this study, a glassceramic material with hydroxyapatite phase was manufactured from industrial and urban wastes. On this material, biofilms from the microorganisms usually appearing in wastewater were developed. Batch assays were made using different heavy metals to analyze glassceramic material capacity to retain these elements from an aqueous medium in biofilm presence and absence. The results suggest that microorganisms are implicated in the removing of heavy metals from the aqueous medium and open the possibility to use the glassceramic material in a bioremediation process.

En este trabajo se elaboró un material vitrocerámico conteniendo la fase de hidroxiapatita, partiendo de residuos industriales y urbanos. Sobre la superficie del material se desarrollaron biopelículas de los microorganismos que aparecen habitualmente en las aguas residuales. Se hicieron ensayos de retención usando distintos metales pesados para evaluar la capacidad del material de eliminar tales elementos de un medio acuoso en presencia y ausencia de la biopelícula. Los resultados ponen de manifiesto la participación microbiana en los procesos de eliminación de los metales pesados del medio acuoso y ofrecen la posibilidad de utilizar el material vitrocerámico en un proceso de biorremediación de aguas contaminadas por metales pesados.

Industrial recovered-materials-utilization targets for the metals and metal-products industry

Energy Technology Data Exchange (ETDEWEB)

None

1980-03-01

The National Energy Conservation Policy Act of 1978 directs DOE to set targets for increased utilization of energy-saving recovered materials for certain industries. These targets are to be established at levels representing the maximum feasible increase in utilization of recovered materials that can be achieved progressively by January 1, 1987 and is consistent with technical and economic factors. A benefit to be derived from the increased use of recoverable materials is in energy savings, as state in the Act. Therefore, emhasis on different industries in the metals sector has been related to their energy consumption. The ferrous industry (iron and steel, ferrour foundries and ferralloys), as defined here, accounts for approximately 3%, and all others for the remaining 3%. Energy consumed in the lead and zinc segments is less than 1% each. Emphasis is placed on the ferrous scrap users, followed by the aluminum and copper industries. A bibliography with 209 citations is included.

In silico optimization of phase-change materials for digital memories: a survey of first-row transition-metal dopants for Ge2Sb2Te5

International Nuclear Information System (INIS)

Skelton, J M; Elliott, S R

2013-01-01

Phase-change materials are the alloys at the heart of an emerging class of next-generation, non-volatile digital memory technologies. However, the widely studied Ge–Sb–Te system possesses several undesirable properties, and enhancing its properties, e.g. by doping, is an area of active research. Various first-row transition-metal dopants have been shown to impart useful property enhancements, but a systematic study of the entire period has yet to be undertaken, and little has been done to investigate their interaction with the host material at the atomic level. We have carried out first-principles computer simulations of the complete phase-change cycle in Ge 2 Sb 2 Te 5 doped with each of the ten first-row transition metals. In this article, we present a comprehensive survey of the electronic, magnetic and optical properties of these doped materials. We discuss in detail their atomic-level structure, and relate the microscopic behaviours of the dopant atoms to their influence on the Ge 2 Sb 2 Te 5 host. By considering an entire family of similar materials, we identify trends and patterns which might be used to predict suitable dopants for optimizing materials for specific phase-change applications. The computational method employed here is general, and this materials-discovery approach could be applied in the future to study other families of potential dopants for such materials. (paper)

NMSS handbook for decommissioning fuel cycle and materials licensees

International Nuclear Information System (INIS)

Orlando, D.A.; Hogg, R.C.; Ramsey, K.M.

1997-03-01

The US Nuclear Regulatory Commission amended its regulations to set forth the technical and financial criteria for decommissioning licensed nuclear facilities. These regulations were further amended to establish additional recordkeeping requirements for decommissioning; to establish timeframes and schedules for the decommissioning; and to clarify that financial assurance requirements must be in place during operations and updated when licensed operations cease. Reviews of the Site Decommissioning Management Plan (SDMP) program found that, while the NRC staff was overseeing the decommissioning program at nuclear facilities in a manner that was protective of public health and safety, progress in decommissioning many sites was slow. As a result NRC determined that formal written procedures should be developed to facilitate the timely decommissioning of licensed nuclear facilities. This handbook was developed to aid NRC staff in achieving this goal. It is intended to be used as a reference document to, and in conjunction with, NRC Inspection Manual Chapter (IMC) 2605, ''Decommissioning Inspection Program for Fuel Cycle and Materials Licensees.'' The policies and procedures discussed in this handbook should be used by NRC staff overseeing the decommissioning program at licensed fuel cycle and materials sites; formerly licensed sites for which the licenses were terminated; sites involving source, special nuclear, or byproduct material subject to NRC regulation for which a license was never issued; and sites in the NRC's SDMP program. NRC staff overseeing the decommissioning program at nuclear reactor facilities subject to regulation under 10 CFR Part 50 are not required to use the procedures discussed in this handbook

Lithium alloys and metal oxides as high-capacity anode materials for lithium-ion batteries

International Nuclear Information System (INIS)

Liang, Chu; Gao, Mingxia; Pan, Hongge; Liu, Yongfeng; Yan, Mi

2013-01-01

Highlights: •Progress in lithium alloys and metal oxides as anode materials for lithium-ion batteries is reviewed. •Electrochemical characteristics and lithium storage mechanisms of lithium alloys and metal oxides are summarized. •Strategies for improving electrochemical lithium storage properties of lithium alloys and metal oxides are discussed. •Challenges in developing lithium alloys and metal oxides as commercial anodes for lithium-ion batteries are pointed out. -- Abstract: Lithium alloys and metal oxides have been widely recognized as the next-generation anode materials for lithium-ion batteries with high energy density and high power density. A variety of lithium alloys and metal oxides have been explored as alternatives to the commercial carbonaceous anodes. The electrochemical characteristics of silicon, tin, tin oxide, iron oxides, cobalt oxides, copper oxides, and so on are systematically summarized. In this review, it is not the scope to retrace the overall studies, but rather to highlight the electrochemical performances, the lithium storage mechanism and the strategies in improving the electrochemical properties of lithium alloys and metal oxides. The challenges and new directions in developing lithium alloys and metal oxides as commercial anodes for the next-generation lithium-ion batteries are also discussed

MAT-FLX: a simplified code for computing material balances in fuel cycle

International Nuclear Information System (INIS)

Pierantoni, F.; Piacentini, F.

1983-01-01

This work illustrates a calculation code designed to provide a materials balance for the electro nuclear fuel cycle. The calculation method is simplified but relatively precise and employs a progressive tabulated data approach

A statistical method for predicting sound absorbing property of porous metal materials by using quartet structure generation set

International Nuclear Information System (INIS)

Guan, Dong; Wu, Jiu Hui; Jing, Li

2015-01-01

Highlights: • A random internal morphology and structure generation-growth method, termed as the quartet structure generation set (QSGS), has been utilized based on the stochastic cluster growth theory for numerical generating the various microstructures of porous metal materials. • Effects of different parameters such as thickness and porosity on sound absorption performance of the generated structures are studied by the present method, and the obtained results are validated by an empirical model as well. • This method could be utilized to guide the design and fabrication of the sound-absorption porous metal materials. - Abstract: In this paper, a statistical method for predicting sound absorption properties of porous metal materials is presented. To reflect the stochastic distribution characteristics of the porous metal materials, a random internal morphology and structure generation-growth method, termed as the quartet structure generation set (QSGS), has been utilized based on the stochastic cluster growth theory for numerical generating the various microstructures of porous metal materials. Then by using the transfer-function approach along with the QSGS tool, we investigate the sound absorbing performance of porous metal materials with complex stochastic geometries. The statistical method has been validated by the good agreement among the numerical results for metal rubber from this method and a previous empirical model and the corresponding experimental data. Furthermore, the effects of different parameters such as thickness and porosity on sound absorption performance of the generated structures are studied by the present method, and the obtained results are validated by an empirical model as well. Therefore, the present method is a reliable and robust method for predicting the sound absorption performance of porous metal materials, and could be utilized to guide the design and fabrication of the sound-absorption porous metal materials

Inorganic material candidates to replace a metallic or non-metallic concrete containment liner

Energy Technology Data Exchange (ETDEWEB)

Seni, C [Atomic Energy of Canada Ltd., Mississauga, ON (Canada); Mills, R H [Toronto Univ., ON (Canada)

1994-12-31

Internal liners for concrete containments are generally organic or metals. They have to be able to inhibit radioactive leakage into the environment, but both types have shortcomings. The results of research to develop a better liner are published in this paper. The best material found was fibre-reinforced mortar. Of the fibres considered, steel, kevlar and glass were the best, each showing advantages and disadvantages. 1 ref., 9 tabs., 12 figs.

Inorganic material candidates to replace a metallic or non-metallic concrete containment liner

International Nuclear Information System (INIS)

Seni, C.; Mills, R.H.

1994-01-01

Internal liners for concrete containments are generally organic or metals. They have to be able to inhibit radioactive leakage into the environment, but both types have shortcomings. The results of research to develop a better liner are published in this paper. The best material found was fibre-reinforced mortar. Of the fibres considered, steel, kevlar and glass were the best, each showing advantages and disadvantages. 1 ref., 9 tabs., 12 figs

Novel bioactive materials developed by simulated body fluid evaluation: Surface-modified Ti metal and its alloys.

Science.gov (United States)

Kokubo, Tadashi; Yamaguchi, Seiji

2016-10-15

Until the discovery of the bone-bonding activity of Bioglass by Hench et al. in the early 1970s, it had not been demonstrated that a synthetic material could bond to living bone without eliciting a foreign body reaction. Since then, various kinds of materials based on calcium phosphate, such as sintered hydroxyapatite and β-tricalcium phosphate have also been shown to bond to living bone. Until the discovery of the bone-bonding activity of Ti metal formed with a sodium titanate surface layer by the present authors in 1996, it had not been shown that a metallic material could bond to living bone. Since then, various kinds of surface-modified Ti metal and its alloys have been found to bond to living bone. Until the discovery of the osteoinduction of porous hydroxyapatite by Yamasaki in 1990, it was unknown whether a synthetic material could induce bone formation even in muscle tissue. Since then, various kinds of porous calcium phosphate ceramics have been shown to induce osteoinduction. Until the discovery of osteoinduction induced by a porous Ti metal formed with a titanium oxide surface layer by Fujibayashi et al. in 2004, it had been unclear whether porous metals would be able to induce osteoinduction. These novel bioactive materials have been developed by systematic research into the apatite formation that occurs on surface-modified Ti metal and its related materials in an acellular simulated body fluid (SBF) having ion concentrations almost equal to those of human blood plasma. Some of the novel bioactive materials based on Ti metal are already in clinical use or clinical trials, such as artificial hip joints and spinal fusion devices. In the present paper, we review how these novel bioactive materials based on Ti metal have been developed based on an evaluation of apatite formation in SBF. Without the SBF evaluation, these novel bioactive materials would most likely never have been developed. On the basis of systematic study of apatite formation on a material

Materials performance in prototype Thermal Cycling Absorption Process (TCAP) columns

International Nuclear Information System (INIS)

Clark, E.A.

1992-01-01

Two prototype Thermal Cycling Absorption Process (TCAP) columns have been metallurgically examined after retirement, to determine the causes of failure and to evaluate the performance of the column container materials in this application. Leaking of the fluid heating and cooling subsystems caused retirement of both TCAP columns, not leaking of the main hydrogen-containing column. The aluminum block design TCAP column (AHL block TCAP) used in the Advanced Hydride Laboratory, Building 773-A, failed in one nitrogen inlet tube that was crimped during fabrication, which lead to fatigue crack growth in the tube and subsequent leaking of nitrogen from this tube. The Third Generation stainless steel design TCAP column (Third generation TCAP), operated in 773-A room C-061, failed in a braze joint between the freon heating and cooling tubes (made of copper) and the main stainless steel column. In both cases, stresses from thermal cycling and local constraint likely caused the nucleation and growth of fatigue cracks. No materials compatibility problems between palladium coated kieselguhr (the material contained in the TCAP column) and either aluminum or stainless steel column materials were observed. The aluminum-stainless steel transition junction appeared to be unaffected by service in the AHL block TCAP. Also, no evidence of cracking was observed in the AHL block TCAP in a location expected to experience the highest thermal shock fatigue in this design. It is important to limit thermal stresses caused by constraint in hydride systems designed to work by temperature variation, such as hydride storage beds and TCAP columns

Activation of human leukocytes on tantalum trabecular metal in comparison to commonly used orthopedic metal implant materials.

Science.gov (United States)

Schildhauer, T A; Peter, E; Muhr, G; Köller, M

2009-02-01

We analyzed leukocyte functions and cytokine response of human leukocytes toward porous tantalum foam biomaterial (Trabecular Metaltrade mark, TM) in comparison to equally sized solid orthopedic metal implant materials (pure titanium, titanium alloy, stainless steel, pure tantalum, and tantalum coated stainless steel). Isolated peripheral blood mononuclear cells (PBMC) and polymorphonuclear neutrophil leukocytes (PMN) were cocultured with equally sized metallic test discs for 24 h. Supernatants were analyzed for cytokine content by enzyme-linked immunosorbent assay. Compared to the other used test materials there was a significant increase in the release of IL (interleukin)-1ra and IL-8 from PMN, and of IL-1ra, IL-6, and TNF-alpha from PBMC in response to the TM material. The cytokine release correlated with surface roughness of the materials. In contrast, the release of IL-2 was not induced showing that mainly myeloid leukocytes were activated. In addition, supernatants of these leukocyte/material interaction (conditioned media, CM) were subjected to whole blood cell function assays (phagocytosis, chemotaxis, bacterial killing). There was a significant increase in the phagocytotic capacity of leukocytes in the presence of TM-conditioned media. The chemotactic response of leukocytes toward TM-conditioned media was significantly higher compared to CM obtained from other test materials. Furthermore, the bactericidal capacity of whole blood was enhanced in the presence of TM-conditioned media. These results indicate that leukocyte activation at the surface of TM material induces a microenvironment, which may enhance local host defense mechanisms.

Three-Dimensional (3D) Printing of Polymer-Metal Hybrid Materials by Fused Deposition Modeling.

Science.gov (United States)

Fafenrot, Susanna; Grimmelsmann, Nils; Wortmann, Martin; Ehrmann, Andrea

2017-10-19

Fused deposition modeling (FDM) is a three-dimensional (3D) printing technology that is usually performed with polymers that are molten in a printer nozzle and placed line by line on the printing bed or the previous layer, respectively. Nowadays, hybrid materials combining polymers with functional materials are also commercially available. Especially combinations of polymers with metal particles result in printed objects with interesting optical and mechanical properties. The mechanical properties of objects printed with two of these metal-polymer blends were compared to common poly (lactide acid) (PLA) printed objects. Tensile tests and bending tests show that hybrid materials mostly containing bronze have significantly reduced mechanical properties. Tensile strengths of the 3D-printed objects were unexpectedly nearly identical with those of the original filaments, indicating sufficient quality of the printing process. Our investigations show that while FDM printing allows for producing objects with mechanical properties similar to the original materials, metal-polymer blends cannot be used for the rapid manufacturing of objects necessitating mechanical strength.

Activation and discharge kinetics of metal hydride electrodes

Energy Technology Data Exchange (ETDEWEB)

Johnsen, Stein Egil

2003-07-01

this activation procedure. Studies of the activity of single metal hydride particles show that each particle has different properties after activation, by hot polarisation, in a porous electrode. The differences in activation among single particles may be due to differences in contact resistance between the individual metal hydride particle and the current collector in the porous electrode, which would result in a current distribution. Annealing of the gas atomised AB{sub 5} type alloy increases the discharge capacity but does not otherwise affect the activation. The corrosion and passivation of metal hydride electrodes of AB{sub 5} type alloys was studied. A high depth of discharge (DOD) decreases the discharge rate capability of the metal hydride electrodes and this is explained by passivation. A surface passivation may enhance particle cracking, which would make the electrode more susceptible to corrosion. The passivation of metal hydride electrodes increases for increasing cut-off-potential (COP) during discharging. This can be explained by an increasing corrosion of the particle surfaces. A corrosion phenomenon was measured at high DOD and correlated to the passivation of the metal hydride particle surface. Lowering the COP can reduce the negative effect of this phenomenon. The cycle life of the gas-atomised material is slightly improved by decreasing the COP but is independent of hot-polarisation activation treatment. Annealing this material significantly improves both discharge capacity and cycle life. A change of surface morphology due to the annealing has been identified and may contribute to the decreased electrode degradation. The formation of hydroxides on the particle surfaces is in general regarded to be negative for the electrode kinetics and is probably responsible for the long time degradation of metal hydride electrodes.

Formation of nanocrystalline surface layers in various metallic materials by near surface severe plastic deformation

Directory of Open Access Journals (Sweden)

Masahide Sato, Nobuhiro Tsuji, Yoritoshi Minamino and Yuichiro Koizumi

2004-01-01

Full Text Available The surface of the various kinds of metallic materials sheets were severely deformed by wire-brushing at ambient temperature to achieve nanocrystalline surface layer. The surface layers of the metallic materials developed by the near surface severe plastic deformation (NS-SPD were characterized by means of TEM. Nearly equiaxed nanocrystals with grain sizes ranging from 30 to 200 nm were observed in the near surface regions of all the severely scratched metallic materials, which are Ti-added ultra-low carbon interstitial free steel, austenitic stainless steel (SUS304, 99.99 wt.%Al, commercial purity aluminum (A1050 and A1100, Al–Mg alloy (A5083, Al-4 wt.%Cu alloy, OFHC-Cu (C1020, Cu–Zn alloy (C2600 and Pb-1.5%Sn alloy. In case of the 1050-H24 aluminum, the depth of the surface nanocrystalline layer was about 15 μm. It was clarified that wire-brushing is an effective way of NS-SPD, and surface nanocrystallization can be easily achieved in most of metallic materials.

Liquid metal MHD studies with non-magnetic and ferro-magnetic structural material

Energy Technology Data Exchange (ETDEWEB)

Patel, A., E-mail: anipatel2009@gmail.com [Institute of Plasma Research, Gandhinagar 382428, Gujarat (India); Bhattacharyay, R. [Institute of Plasma Research, Gandhinagar 382428, Gujarat (India); Swain, P.K.; Satyamurthy, P. [Bhabha Atomic Research Center, Mumbai 400085, Maharashtra (India); Sahu, S.; Rajendrakumar, E. [Institute of Plasma Research, Gandhinagar 382428, Gujarat (India); Ivanov, S.; Shishko, A.; Platacis, E.; Ziks, A. [Institute of Physics, University of Latvia, Salaspils 2169 (Latvia)

2014-10-15

Highlights: • Effect of structural material on liquid metal MHD phenomena is studied. • Two identical test sections, one made of SS316L (non-magnetic) and other made of SS430 (ferromagnetic) structural material, are considered. • Wall electric potential and liquid metal pressure drop are compared under various experimental conditions. • Experimental results suggest screening of external magnetic field for SS430 material below the saturation magnetic field. - Abstract: In most of the liquid metal MHD experiments reported in the literature to study liquid breeder blanket performance, SS316/SS304 grade steels are used as the structural material which is non-magnetic. On the other hand, the structural material for fusion blanket systems has been proposed to be ferritic martensitic grade steel (FMS) which is ferromagnetic in nature. In the recent experimental campaign, liquid metal MHD experiments have been carried out with two identical test sections: one made of SS316L (non-magnetic) and another with SS430 (ferromagnetic), to compare the effect of structural materials on MHD phenomena for various magnetic fields (up to 4 T). The maximum Hartmann number and interaction number are 1047 and 300, respectively. Each test section consists of square channel (25 mm × 25 mm) cross-section with two U bends, with inlet and outlet at the middle portion of two horizontal legs, respectively. Pb–Li enters into the test section through a square duct and distributed into two parallel paths through a partition plate. In each parallel path, it travels ∼0.28 m length in plane perpendicular to the magnetic field and faces two 90° bends before coming out of the test section through a single square duct. The wall electrical potential and MHD pressure drop across the test sections are compared under identical experimental conditions. Similar MHD behavior is observed with both the test section at higher value of the magnetic field (>2 T)

3rd Workshop on metal ceramic materials for functional applications

International Nuclear Information System (INIS)

Korb, G.

1997-01-01

This workshop contains contributions about materials and processing, characterization and modeling of properties and applications of metallic ceramics and composite structures. It was held on behalf of the Taiwan-Austrian scientific collaboration in Vienna, June 4 th - 6 th 1997. (Suda)

Randomly grain growth in metallic materials

Energy Technology Data Exchange (ETDEWEB)

Ramirez, A. [Instituto Politecnico Nacional, (SEPI-ESIME), Unidad Profesional Ticoman, Av. Ticoman 600, Del. G.A.M., C.P. 07340 Distrito Federal, Mexico (Mexico); Instituto Politecnico Nacional, (SEPI-ESIQIE), Unidad Profesional Zacatenco, Edif. 6 y Edif. Z planta baja C.P.07300, Distrito Federal, Mexico (Mexico)], E-mail: adaramil@yahoo.com.mx; Chavez, F. [Instituto Politecnico Nacional, (SEPI-ESIQIE), Unidad Profesional Zacatenco, Edif. 6 y Edif. Z planta baja C.P.07300, Distrito Federal, Mexico (Mexico); Demedices, L. [Instituto Politecnico Nacional, (SEPI-ESIME), Unidad Profesional Ticoman, Av. Ticoman 600, Del. G.A.M., C.P. 07340 Distrito Federal, Mexico (Mexico); Instituto Politecnico Nacional, (SEPI-ESIQIE), Unidad Profesional Zacatenco, Edif. 6 y Edif. Z planta baja C.P.07300, Distrito Federal, Mexico (Mexico); Cruz, A.; Macias, M. [Instituto Politecnico Nacional, (SEPI-ESIQIE), Unidad Profesional Zacatenco, Edif. 6 y Edif. Z planta baja C.P.07300, Distrito Federal, Mexico (Mexico)

2009-10-30

Computational modeling of grain structures is a very important topic in materials science. In this work, the development of the computational algorithms for a mathematical model to predict grain nucleation and grain growth is presented. The model place a number of nucleated points randomly in a liquid pool according with the solid and liquid fractions (X{sub sol} and X{sub liq}) of metal solute and the local temperature distribution (SS{sub I,J}). Then these points grows isotropically until obtain a grain structure with straight interfaces. Different grain morphologies such as columnar and equiaxed can be obtained as a function of the temperature distributions and growth directions.

Randomly grain growth in metallic materials

International Nuclear Information System (INIS)

Ramirez, A.; Chavez, F.; Demedices, L.; Cruz, A.; Macias, M.

2009-01-01

Computational modeling of grain structures is a very important topic in materials science. In this work, the development of the computational algorithms for a mathematical model to predict grain nucleation and grain growth is presented. The model place a number of nucleated points randomly in a liquid pool according with the solid and liquid fractions (X sol and X liq ) of metal solute and the local temperature distribution (SS I,J ). Then these points grows isotropically until obtain a grain structure with straight interfaces. Different grain morphologies such as columnar and equiaxed can be obtained as a function of the temperature distributions and growth directions.

Levels of immunoreactive inhibin-like material in urine during the menstrual cycle

International Nuclear Information System (INIS)

Dandekar, S.P.; Vanage, G.R.; Arbatti, N.J.; Sheth, A.R.

1983-01-01

Using a specific and sensitive radioimmunoassay, the authors determined levels of inhibinlike material in the urine of eight healthy women with normal menstrual cycle length of 28 +- 4 days. The results revealed a cyclic variation in urinary immunoreactive inhibin levels during the menstrual cycles, with a sharp rise in levels three to four days prior to luteinizing hormone (LH) and follicle-stimulating hormone (FSH) peaks. These levels of immunoreactive inhibin may thus serve as a parameter to detect impending LH surge. (author)

Nuclear-Fuel-Cycle Research Program: availability of geotoxic material

Energy Technology Data Exchange (ETDEWEB)

Wachter, B.G.; Kresan, P.L.

1982-09-01

This report represents an analog approach to the characterization of the environmental behavior of geotoxic waste materials (toxic material emplaced in the earth's crust) as drawn from literature on the Oklo natural fission reactors and uranium ore deposits relative to radioactive wastes, and hydrothermal metal ore deposits relative to stable toxic wastes. The natural analog data were examined in terms of mobility and immobility of selected radioactive or stable waste elements and are presented in matrix relationship with their prime geochemical variables. A numerical system of ranking those relationships for purposes of hazard-indexing is proposed. Geochemical parameters (especially oxidation/reduction potential) are apparently more potent mobilizers/immobilizers than geological or hydrological conditions in many, if not most, geologic environments for most radioactive waste elements. Heavy metal wastes, by analogy to hydrothermal ore systems and geothermal systems, are less clear in their behavior but similar geochemical patterns do apply. Depth relationships between geochemical variables and waste element behavior show some surprises. It is significantly indicated that for waste isolation, deeper is not necessarily better geochemically. Relatively shallow isolation in host rocks such as shale could offer maximum immobility. This paper provides a geochemical outline for examining analog models as well as a departure point for improved quantification of geological and geochemical indexing of toxic waste hazards.

Nuclear-Fuel-Cycle Research Program: availability of geotoxic material

International Nuclear Information System (INIS)

Wachter, B.G.; Kresan, P.L.

1982-09-01

This report represents an analog approach to the characterization of the environmental behavior of geotoxic waste materials (toxic material emplaced in the earth's crust) as drawn from literature on the Oklo natural fission reactors and uranium ore deposits relative to radioactive wastes, and hydrothermal metal ore deposits relative to stable toxic wastes. The natural analog data were examined in terms of mobility and immobility of selected radioactive or stable waste elements and are presented in matrix relationship with their prime geochemical variables. A numerical system of ranking those relationships for purposes of hazard-indexing is proposed. Geochemical parameters (especially oxidation/reduction potential) are apparently more potent mobilizers/immobilizers than geological or hydrological conditions in many, if not most, geologic environments for most radioactive waste elements. Heavy metal wastes, by analogy to hydrothermal ore systems and geothermal systems, are less clear in their behavior but similar geochemical patterns do apply. Depth relationships between geochemical variables and waste element behavior show some surprises. It is significantly indicated that for waste isolation, deeper is not necessarily better geochemically. Relatively shallow isolation in host rocks such as shale could offer maximum immobility. This paper provides a geochemical outline for examining analog models as well as a departure point for improved quantification of geological and geochemical indexing of toxic waste hazards

Nanoporous Polymer-Ceramic Composite Electrolytes for Lithium Metal Batteries

KAUST Repository

Tu, Zhengyuan

2013-09-16

A nanoporous composite material that offers the unique combination of high room-temperature ionic conductivity and high mechanical modulus is reported. When used as the separator/electrolyte in lithium batteries employing metallic lithium as anode, the material displays unprecedented cycling stability and excellent ability to prevent premature cell failure by dendrite-induced short circuits © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Geochemical and hydrodynamic controls on arsenic and trace metal cycling in a seasonally stratified US sub-tropical reservoir

International Nuclear Information System (INIS)

Brandenberger, Jill M.; Louchouarn, Patrick; Herbert, Bruce; Tissot, Philippe

2004-01-01

The phase distribution of trace metals and oxyanions was investigated within a South Texas watershed hosting a high density of surface uranium mine pits and tailings. The objectives of the study were to evaluate the potential impact of these old uranium mining sites on the watershed with particular emphasis on spatial and temporal changes in water quality of a reservoir that serves as the major source of freshwater to a population of ∼ 350,000 people in the region. A livestock pond, bordered by uranium mine tailings, was used as a model case-study site to evaluate the cycling of uranium mine-derived oxyanions under changing redox conditions. Although the pond showed seasonal thermal and chemical stratification, geochemical cycling of metals was limited to Co and Pb, which seemed to be mostly associated with redox cycling of Mn mineral phases, and U, which suggested reductive precipitation in the ponds hypolimnion. Uranium levels, however, were too low to support strong inputs from th e tailings into the water column of the pond. The strong relations observed between particulate Cr, Cs, V and Fe suggest that these metals are associated with a stable particulate phase (probably allochthonous aluminosilicates) enriched in unreactive iron. This observation is supported by a parallel relationship in sediments collected across a broad range of sediment depositional processed (and histories) in the basin. Arsenic, though selectively enriched in the ponds water column, remained stable and mostly in solution throughout the depth of the profile and showed no sign of geochemical cycling or interaction with Fe-rich particles. We found no evidence of anthropogenic impacts of U mines beyond the purely local scale. Arsenic does decrease in concentration downstream of uranium mining sites but its presence within the Nueces drainage basin is related to interactions between surface and ground waters with uranium-rich geological formations rather than long-scale transport of

High-Performance Corrosion-Resistant Materials: Iron-Based Amorphous-Metal Thermal-Spray Coatings: SAM HPCRM Program ? FY04 Annual Report ? Rev. 0 - DARPA DSO & DOE OCRWM Co-Sponsored Advanced Materials Program

Energy Technology Data Exchange (ETDEWEB)

Farmer, J; Haslam, J; Wong, F; Ji, S; Day, S; Branagan, D; Marshall, M; Meacham, B; Buffa, E; Blue, C; Rivard, J; Beardsley, M; Buffa, E; Blue, C; Rivard, J; Beardsley, M; Weaver, D; Aprigliano, L; Kohler, L; Bayles, R; Lemieux, E; Wolejsza, T; Martin, F; Yang, N; Lucadamo, G; Perepezko, J; Hildal, K; Kaufman, L; Heuer, A; Ernst, F; Michal, G; Kahn, H; Lavernia, E

2007-09-19

The multi-institutional High Performance Corrosion Resistant Materials (HPCRM) Team is cosponsored by the Defense Advanced Projects Agency (DARPA) Defense Science Office (DSO) and the Department of Energy (DOE) Office of Civilian Radioactive Waste Management (OCRWM), and has developed new corrosion-resistant, iron-based amorphous metals that can be applied as coatings with advanced thermal spray technology. Two compositions have corrosion resistance superior to wrought nickel-based Alloy C-22 (UNS No. N06022) in very aggressive environments, including concentrated calcium-chloride brines at elevated temperature. Corrosion costs the Department of Defense billions of dollars every year, with an immense quantity of material in various structures undergoing corrosion. For example, in addition to fluid and seawater piping, ballast tanks, and propulsions systems, approximately 345 million square feet of structure aboard naval ships and crafts require costly corrosion control measures. The use of advanced corrosion-resistant materials to prevent the continuous degradation of this massive surface area would be extremely beneficial. The Fe-based corrosion-resistant, amorphous-metal coatings under development may prove of importance for applications on ships. Such coatings could be used as an 'integral drip shield' on spent fuel containers, as well as protective coatings that could be applied over welds, thereby preventing exposure to environments that might cause stress corrosion cracking. In the future, such new high-performance iron-based materials could be substituted for more-expensive nickel-based alloys, thereby enabling a reduction in the $58-billion life cycle cost for the long-term storage of the Nation's spent nuclear fuel by tens of percent.

Ammonium generation during SRAT cycle

International Nuclear Information System (INIS)

Hsu, C.W.

1992-01-01

During the IDMS noble-metal demonstration runs ammonium nitrate deposition was found in the vessel vent system of the feed preparation area. In the bench-scale experiments of studying the hydrogen generation during the sludge treatment cycle, ammonium ion production was also monitored. It was found that: During a simulation of the DWPF Cold Chemical Runs SRAT cycle no detectable amount of ammonium ions was generated when treating a non-noble-metal containing sludge simulant according to the nitric acid flowsheet. Ammonium ions were generated during the SRAT-SME cycle when treating the noble-metal containing sludge with either formic acid or nitric acid/late-washing PHA. This is due to the reaction between formic acid and nitrate catalyzed by the noble metals in the sludge simulant. Ammonium ion production closely followed the hydrogen evolution from the catalytic decomposition of formic acid. This report summarizes the results of the production of ammonia during the SRAT cycle

U.S. FUEL CYCLE TECHNOLOGIES R&D PROGRAM FOR NEXT GENERATION NUCLEAR MATERIALS MANAGEMENT

Directory of Open Access Journals (Sweden)

M.C. MILLER

2013-11-01

Full Text Available The U.S. Department of Energy's Fuel Cycle Technologies R&D program under the Office of Nuclear Energy is working to advance technologies to enhance both the existing and future fuel cycles. One thrust area is in developing enabling technologies for next generation nuclear materials management under the Materials Protection, Accounting and Control Technologies (MPACT Campaign where advanced instrumentation, analysis and assessment methods, and security approaches are being developed under a framework of Safeguards and Security by Design. An overview of the MPACT campaign's activities and recent accomplishments is presented along with future plans.

3rd Workshop on metal ceramic materials for functional applications

Energy Technology Data Exchange (ETDEWEB)

Korb, G [Oesterreichisches Forschungszentrum Seibersdorf, 2444 Seibersdorf (Austria)

1998-12-31

This workshop contains contributions about materials and processing, characterization and modeling of properties and applications of metallic ceramics and composite structures. It was held on behalf of the Taiwan-Austrian scientific collaboration in Vienna, June 4{sup th} - 6{sup th} 1997. (Suda)

Cyclic catalytic upgrading of chemical species using metal oxide materials

Science.gov (United States)

White, James H; Schutte, Erick J; Rolfe, Sara L

2013-05-07

Processes are disclosure which comprise alternately contacting an oxygen-carrying catalyst with a reducing substance, or a lower partial pressure of an oxidizing gas, and then with the oxidizing gas or a higher partial pressure of the oxidizing gas, whereby the catalyst is alternately reduced and then regenerated to an oxygenated state. In certain embodiments, the oxygen-carrying catalyst comprises at least one metal oxide-containing material containing a composition having the following formulas: (a) Ce.sub.xB.sub.yB'.sub.zB''O.sub..delta., wherein B=Ba, Sr, Ca, or Zr; B'=Mn, Co, and/or Fe; B''=Cu; 0.01Ba, Ca, La, or K; 0.02material itself or as a support for said unary or binary metal oxides.

Certification of a niobium metal reference material for neutron dosimetry (EC nuclear reference material 526)

International Nuclear Information System (INIS)

Ingelbrecht, C.; Pauwels, J.

1990-01-01

Niobium metal, of 99.999% nominal purity, in the form of 0.02 and 0.1 mm thick foil and of 0.5 mm diameter wire, has been certified for its tantalum mass fraction. The certified value of the tantalum mass fraction is 0.3 ± 0.09 mg. Kg -1 , and is based on 70 results obtained by six independent laboratories by neutron activation analysis or inductively coupled plasma mass spectrometry. The material is intended to be used as a reference material in neutron metrology

Blanket materials for DT fusion reactors

International Nuclear Information System (INIS)

Smith, D.L.

1981-01-01

This paper presents an overview of the critical materials issues that must be considered in the development of a tritium breeding blanket for a tokamak fusion reactor that operates on the D-T-Li fuel cycle. The primary requirements of the blanket system are identified and the important criteria that must be considered in the development of blanket technology are summarized. The candidate materials are listed for the different blanket components, e.g., breeder, coolant, structure and neutron multiplier. Three blanket concepts that appear to offer the most potential are: (1) liquid-metal breeder/coolant, (2) liquid-metal breeder/separate coolant, and (3) solid breeder/separate coolant. The major uncertainties associated with each of the design concepts are discussed and the key materials R and D requirements for each concept are identified

Electron dynamics in metals and semiconductors in strong THz fields

DEFF Research Database (Denmark)

Jepsen, Peter Uhd

2017-01-01

Semiconductors and metals respond to strong electric fields in a highly nonlinear fashion. Using single-cycle THz field transients it is possible to investigate this response in regimes not accessible by transport-based measurements. Extremely high fields can be applied without material damage...

A Linkage Between Parent Materials of Soil and Potential Risk of Heavy Metals in Yunnan province, China

Science.gov (United States)

Cheng, X.

2015-12-01

A large area exceeding soil quality standards for heavy metals in South western China has been identified previously reported on a nationwide survey of soil pollution, yet the ecological risk of heavy metal in soil is unknown or uncertainty.To assess thoroughly the ecological risk in this region, seven soil profiles with a depth of 2m on the different parent materials of soil were conducted in Yunnan province, China, and the level of total concentrations and the fraction of water soluble, ion exchangeable, carbonates, humic acid, iron and manganese oxides and organic matter of As, Cd, Hg and Pb was investigated in soil profiles. The results indicate that parent materials of soil critically influenced the ecological risk of heavy metal.The fraction of water soluble and ion exchangeable of Cd and Hg in alluvial material and in terrigenous clastic rocks showed 2-6 times higher than those in carbonate rock; As and Pb has almost same fraction of water soluble and ion exchangeable in three parent materials of soil.The findings suggest that parent materials of soil play a critical role in ecological risk of heavy metal.Thus, more studies are needed to better understand a linkage between the parent materials of soil, different soil-forming processes and the potential risk of heavy metals under various geographic conditions, which is the key for the evaluating soil quality and food safety. Those soils with high concentration of Cd and Hg originated alluvial material and terrigenous clastic rocks need to be continuously monitored before determining a cost-effective remediation technology. Keywords: Heavy metals; Ecological risk;Parent materials of soil;China

Revolutions in energy input and material cycling in Earth history and human history

Science.gov (United States)

Lenton, Timothy M.; Pichler, Peter-Paul; Weisz, Helga

2016-04-01

Major revolutions in energy capture have occurred in both Earth and human history, with each transition resulting in higher energy input, altered material cycles and major consequences for the internal organization of the respective systems. In Earth history, we identify the origin of anoxygenic photosynthesis, the origin of oxygenic photosynthesis, and land colonization by eukaryotic photosynthesizers as step changes in free energy input to the biosphere. In human history we focus on the Palaeolithic use of fire, the Neolithic revolution to farming, and the Industrial revolution as step changes in free energy input to human societies. In each case we try to quantify the resulting increase in energy input, and discuss the consequences for material cycling and for biological and social organization. For most of human history, energy use by humans was but a tiny fraction of the overall energy input to the biosphere, as would be expected for any heterotrophic species. However, the industrial revolution gave humans the capacity to push energy inputs towards planetary scales and by the end of the 20th century human energy use had reached a magnitude comparable to the biosphere. By distinguishing world regions and income brackets we show the unequal distribution in energy and material use among contemporary humans. Looking ahead, a prospective sustainability revolution will require scaling up new renewable and decarbonized energy technologies and the development of much more efficient material recycling systems - thus creating a more autotrophic social metabolism. Such a transition must also anticipate a level of social organization that can implement the changes in energy input and material cycling without losing the large achievements in standard of living and individual liberation associated with industrial societies.

Analysis of Metallized Teflon(trademark) Film Materials Performance on Satellites

Science.gov (United States)

Pippin, H. Gary; Normand, Eugene; Wolf, Suzanne L. B.; Kamenetzky, Rachel; Kauffman, William J., Jr. (Technical Monitor)

2002-01-01

Laboratory and on-orbit performance data for two common thermal control materials, silver- and aluminum-backed (metallized) fluorinated ethyl-propylene (TER) was collected from a variety of sources and analyzed. This paper demonstrates that the change in solar absorptance, alpha, is a strong function of particulate radiation for these materials. Examination of additional data shows that the atomic oxygen recession rate is a strong function of solar exposure with an induction period of between 25 to 50 equivalent solar hours. The relationships determined in this analysis were incorporated into an electronic knowledge base, the 'Spacecraft Materials Selector,' under NASA contract NAS8-98213.

Degradation of metallic materials studied by correlative tomography

Science.gov (United States)

Burnett, T. L.; Holroyd, N. J. H.; Lewandowski, J. J.; Ogurreck, M.; Rau, C.; Kelley, R.; Pickering, E. J.; Daly, M.; Sherry, A. H.; Pawar, S.; Slater, T. J. A.; Withers, P. J.

2017-07-01

There are a huge array of characterization techniques available today and increasingly powerful computing resources allowing for the effective analysis and modelling of large datasets. However, each experimental and modelling tool only spans limited time and length scales. Correlative tomography can be thought of as the extension of correlative microscopy into three dimensions connecting different techniques, each providing different types of information, or covering different time or length scales. Here the focus is on the linking of time lapse X-ray computed tomography (CT) and serial section electron tomography using the focussed ion beam (FIB)-scanning electron microscope to study the degradation of metals. Correlative tomography can provide new levels of detail by delivering a multiscale 3D picture of key regions of interest. Specifically, the Xe+ Plasma FIB is used as an enabling tool for large-volume high-resolution serial sectioning of materials, and also as a tool for preparation of microscale test samples and samples for nanoscale X-ray CT imaging. The exemplars presented illustrate general aspects relating to correlative workflows, as well as to the time-lapse characterisation of metal microstructures during various failure mechanisms, including ductile fracture of steel and the corrosion of aluminium and magnesium alloys. Correlative tomography is already providing significant insights into materials behaviour, linking together information from different instruments across different scales. Multiscale and multifaceted work flows will become increasingly routine, providing a feed into multiscale materials models as well as illuminating other areas, particularly where hierarchical structures are of interest.

Achievement report on research and development in the Sunshine Project in fiscal 1979. Research on hydrogen manufacturing technologies (Research on equipment materials for iodine system cycle); 1979 nendo netsukagakuho ni yoru suiso seizo gijutsu no kenkyu seika hokokusho. Yosokei cycle no sochi zairyo no kenkyu

Energy Technology Data Exchange (ETDEWEB)

NONE

1980-03-01

From among researches on hydrogen manufacturing technologies using thermo-chemistry in the Sunshine Project, discussions were given on equipment materials, with the second-stage reaction in the iodine system cycle as the object. This paper describes achievements in fiscal 1979. The reaction produces MgO, I{sub 2} and O{sub 2} from Mg(IO{sub 3}){sub 2}. Corrosion tests were performed by using test pieces made of Ni alloy, iron-Ni-Cr alloy, Ti alloy, Zr alloy, Nb and Ta. These materials are thought to have excellent corrosion resistance in high temperature gaseous phase composed of iodine, oxygen and water. Corrosion tests were carried out also by using sheet formed test pieces of 24 kinds of alloys and six kinds of commercially available non-ferrous metallic materials in different temperatures and atmospheres, mainly the iodine plus oxygen plus H{sub 2}O mixed gas atmosphere at 600 degrees C. The corrosion resistance of the tested materials can be divided into three ranks. Materials having relatively good resistance were Ni-50Cr alloy and Co group alloy. Materials having good corrosion resistance are very little affected by water content. The higher the temperature, the more the metal corrosivity has increased. Preliminary discussions were given on pipe formability in materials having good corrosion resistance as the equipment piping materials. Their mechanical properties were also tested. This paper also describes corrosion resistance tests under heat transferring condition by using pipe-formed test pieces. (NEDO)

Levels of immunoreactive inhibin-like material in urine during the menstrual cycle

Energy Technology Data Exchange (ETDEWEB)

Dandekar, S.P.; Vanage, G.R.; Arbatti, N.J.; Sheth, A.R. (Institute for Research in Reproduction, Parel, Bombay (India))

1983-12-01

Using a specific and sensitive radioimmunoassay, the authors determined levels of inhibin-like material in the urine of eight healthy women with normal menstrual cycle length of 28 +- 4 days. The results revealed a cyclic variation in urinary immunoreactive inhibin levels during the menstrual cycles, with a sharp rise in levels three to four days prior to luteinizing hormone (LH) and follicle-stimulating hormone (FSH) peaks. These levels of immunoreactive inhibin may thus serve as a parameter to detect impending LH surge. 23 refs.

Summary of the Effects of Two Years of Hygro-Thermal Cycling on a Carbon/Epoxy Composite Material

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