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Sample records for leo materials selection

  1. Materials selection for long life in LEO: a critical evaluation of atomic oxygen testing with thermal atom systems

    International Nuclear Information System (INIS)

    Koontz, S.L.; Kuminecz, J.; Leger, L.; Nordine, P.

    1988-01-01

    The use of thermal atom test methods as a materials selection and screening technique for low-Earth orbit (LEO) spacecraft is critically evaluated. The chemistry and physics of thermal atom environments are compared with the LEO environment. The relative reactivities of a number of materials determined to be in thermal atom environments are compared to those observed in LEO and in high quality LEO simulations. Reaction efficiencies measured in a new type of thermal atom apparatus are one-hundredth to one-thousandth those observed in LEO, and many materials showing nearly identical reactivities in LEO show relative reactivities differing by as much as a factor of 8 in thermal atom systems. A simple phenomenological kinetic model for the reaction of oxygen atoms with organic materials can be used to explain the differences in reactivity in different environments. Certain specific thermal test environments can be used as reliable materials screening tools. Using thermal atom methods to predict material lifetime in LEO requires direct calibration of the method against LEO data or high quality simulation data for each material

  2. Leo

    Science.gov (United States)

    Murdin, P.

    2000-11-01

    (the Lion; abbrev. Leo, gen. Leonis; area 947 sq. deg.) A northern zodiacal constellation which lies between Cancer and Virgo, and culminates at midnight in early March. It represents the Nemean lion that, in Greek mythology, Hercules killed as the first of his 12 labors. Its brightest stars were cataloged by Ptolemy (c. AD 100-175) in the Almagest....

  3. Microencapsulação de óleo essencial de laranja: seleção de material de parede Microencapsulation of orange essential oil: wall material selection

    Directory of Open Access Journals (Sweden)

    Diego P. R. Ascheri

    2003-12-01

    Full Text Available No presente trabalho se procedeu à comparação de agentes microencapsulantes, material de parede (mp, na microencapsulação de óleo essencial de laranja (material ativo através da secagem por atomização. Foram preparadas três amostras de emulsões pela adição de óleo essencial de laranja a uma solução aquosa do mp composta de capsul (5,0, 0,0 e 10,0%, goma arábica (5,0, 10,0 e 0,0% sendo constante para as três amostras maltodextrina (36,0%, água (44,0% e óleo essencial (10,0%. Foram avaliadas as curvas de secagem das emulsões frente à retenção do óleo essencial de laranja e a tendência de formação de dobras superficiais das partículas e verificou-se a hipótese "menor a tendência de formação de dobras na superfície das microcápsulas maior a retenção de material ativo". A microencapsulação foi obtida pela secagem por atomização, com temperaturas de 220ºC e 110ºC do ar de entrada e de saída da câmara de secagem, respectivamente, e com atomizador rotativo (20.000rpm. A comparação das microcápsulas obtidas a partir das três amostras de emulsões mostrou que aquela preparada com 10,0% de capsul e 0,0% de goma arábica apresentou o maior resultado. O período de taxa constante de secagem desta mistura é curto e com maior retenção de umidade após a secagem. As microcápsulas obtidas apresentaram maior retenção de óleo essencial e dobras superficiais menos pronunciadas decorrentes do menor entumescimento das gotículas durante a secagem.The present work is an experimental development to study the performance of the encapsulation agents for orange essential oil in a spray drying process. The emulsion to be dried was prepared by adding the oil to an aqueous solution of the wall material. Three different cases were studied having respectively capsul (5.0%, 0.0% and 10.0% and arabic gum (5.0%, 10.0% and 0.0% with 36.0% maltodextrin, 44.0% water and 10.0% essential oil. Retention of active material

  4. Material interactions with the Low Earth Orbital (LEO) environment: Accurate reaction rate measurements

    Science.gov (United States)

    Visentine, James T.; Leger, Lubert J.

    1987-01-01

    To resolve uncertainties in estimated LEO atomic oxygen fluence and provide reaction product composition data for comparison to data obtained in ground-based simulation laboratories, a flight experiment has been proposed for the space shuttle which utilizes an ion-neutral mass spectrometer to obtain in-situ ambient density measurements and identify reaction products from modeled polymers exposed to the atomic oxygen environment. An overview of this experiment is presented and the methodology of calibrating the flight mass spectrometer in a neutral beam facility prior to its use on the space shuttle is established. The experiment, designated EOIM-3 (Evaluation of Oxygen Interactions with Materials, third series), will provide a reliable materials interaction data base for future spacecraft design and will furnish insight into the basic chemical mechanisms leading to atomic oxygen interactions with surfaces.

  5. Estudo das características de adsorção de água e da estabilidade das microcápsulas de óleo essencial de laranja na seleção de material de parede Water adsorption characteristics and stability of orange essential oil microcapsules in the wall material selection

    Directory of Open Access Journals (Sweden)

    D. P. R. ASCHERI

    1999-12-01

    Full Text Available Este trabalho consistiu no estudo e comparação das características de adsorção de água de três amostras de microcápsulas de óleo essencial de laranja, obtidas pela secagem por atomização de três diferentes emulsões preparadas pela adição de óleo essencial de laranja (oel, a uma solução aquosa de material de parede (mp constituída de capsul (5,0, 0,0 e 10,0%, goma arábica (5,0, 10,0 e 0,0% sendo constante para as três emulsões a maltodextrina (36,0%, água (44,0% e óleo essencial (10,0%. A microencapsulação foi realizada a 220 e 110° C de ar de entrada e saída do secador usando um atomizador rotativo a 20.000rpm. Com base à determinação das isotermas de adsorção de água a 30, 40 e 50° C e usando o modelo de GAB para ajustar os pontos experimentais foram avaliadas as características das isotermas, a estabilidade e área superficial de adsorção de água das diferentes amostras de microcápsulas obtidas. Os resultados indicaram ser importante o estudo das características de adsorção de água para estimar a estabilidade das microcápsulas de oel e a comparação destas mostrou que as microcápsulas obtidas pela secagem por atomização da emulsão preparada com 5,0% de capsul e 5,0% de goma arábica apresentaram o melhor resultado.This work consisted of the study and comparison of the water adsorption characteristics of three samples orange essential oil microcapsules obtained by spray drying of three different emulsions prepared by the addition of orange essential oil (oel to an aqueous solution of wall material (mp constituted of capsul (5.0, 0.0 and 10.0%, arabic gum (5.0, 10.0 and 0.0% being constant for the three emulsions the maltodextrin (36.0%, water (44.0% and essential oil (10.0%. The microencapsulation was accomplished to 220 and 110°C of entrance air and exit of the dryer using a wheel atomizer to 20,000rpm. With base to the determination of the water adsorption isotherms to 30, 40 and 50°C and

  6. Skateboard deck materials selection

    Science.gov (United States)

    Liu, Haoyu; Coote, Tasha; Aiolos; Charlie

    2018-03-01

    The goal of this project was to identify the ideal material for a skateboard deck under 200 in price, minimizing the weight. The material must have a fracture toughness of 5 MPa/m2, have a minimum lifetime of 10, 000 cycles and must not experience brittle fracture. Both single material and hybrid solutions were explored. When further selecting to minimize weight, woods were found to be the best material. Titanium alloy-wood composites were explored to determine the optimal percentage composition of each material.A sandwich panel hybrid of 50% titanium alloy and 50% wood (Ti-Wood) was found to be the optimum material, performing better than the currently used plywood.

  7. Prey selection of lions Panthera leo in a small, enclosed reserve

    Directory of Open Access Journals (Sweden)

    R.J. Power

    2002-12-01

    Full Text Available Annual trends in numbers of ungulate species on a 15 km² reserve from 1993 to 1998, were evaluated in the context of lion Panthera leo reintroduction during 1996, and subsequent predation by them. The ungulate prey base was enumerated annually by aerial counts and a road count that took place during 1998. The lion prey record was obtained from direct observations of a radio-located pride of eight lions and daily reserve management records. All ungulate species that underwent precipituous declines were also the most important prey to lions, comprising over 80 % of their prey, and they were preyed upon according to their availability. Lion predation was causal for the declines in wildebeest Connochaetes taurinus, Blesbok Damaliscus pygargus phillipsi and Warthog Phacochoerus africana, while the decline in Kudu Tragelaphus strepsiceros was only partly ascribed to lions, as other non-lion related mortality sources were identified. The only ungulate species to increase subsequent to lion reintroduction was the Impala Aepyceros melampus, which was furthermore under-selected by lions. The uncontrolled population growth of Impala could have elicited ecological degradation, and it was advised to either not stock Impala, or otherwise control their numbers if lions are unable to do so. Lion hunting success and kill rate, were 21 % (n = 63 and 1 kill/4.4 days, respectively. Three bushpigs Potamochoerus larvatus were killed but not utilised,and this finding is corroborated by an intensive study in Kwazulu-Natal, and this aversion is discussed. Predators can cause unprecedented declines of their prey where the prey are confined to small reserves that have no refuge from predation. On an annual basis, prey may need to be augmented to sustain predators on small reserves

  8. Materials selection in mechanical design

    International Nuclear Information System (INIS)

    Ashby, M.F.; Cebon, D.

    1993-01-01

    A novel materials-selection procedure has been developed and implemented in software. The procedure makes use of Materials Selection Charts: a new way of displaying material property data; and performance indices: combinations of material properties which govern performance. Optimisation methods are employed for simultaneous selection of both material and shape. (orig.)

  9. Materials selection in mechanical design

    OpenAIRE

    Ashby , M.; Cebon , D.

    1993-01-01

    A novel materials-selection procedure has been developed and implemented in software. The procedure makes use of Materials Selection Charts: a new way of displaying material property data; and performance indices: combinations of material properties which govern performance. Optimisation methods are employed for simultaneous selection of both material and shape.

  10. Characterization of selected LDEF polymer matrix resin composite materials

    Science.gov (United States)

    Young, Philip R.; Slemp, Wayne S.; Witte, William G., Jr.; Shen, James Y.

    1991-01-01

    The characterization of selected graphite fiber reinforced epoxy (934 and 5208) and polysulfone (P1700) matrix resin composite materials which received 5 years and 10 months of exposure to the LEO environment on the Long Duration Exposure Facility is reported. Resin loss and a decrease in mechanical performance as well as dramatic visual effects were observed. However, chemical characterization including infrared, thermal, and selected solution property measurements showed that the molecular structure of the polymeric matrix had not changed significantly in response to this exposure. The potential effect of a silicon-containing molecular contamination of these specimens is addressed.

  11. Materials selection for cutting tools

    International Nuclear Information System (INIS)

    Burkhis, Adel M.

    2008-01-01

    The selection of proper tool steel for a given application is a difficult task. So; the most important selection factors in choosing cutting tool materials are based on their tool material requirements, cutting tool design and service conditions which is mainly considered as functional requirements. The processability requirements concerns in heat treat ability of the material tool. The classification of these tool materials were discussed with their properties requirement and percent of alloying element which is added to give best properties with a little increase in cost that highly appear in comparison of the selection. The cutting tool materials were evaluated based on two cases; The first was in case of rough surface; the high speed steels is the best material and the other was the ceramic material is the highest performance in cutting of soft or high rate of metal removal. (author)

  12. Materials Selection for Aerospace Systems

    Science.gov (United States)

    Arnold, Steven M.; Cebon, David; Ashby, Mike

    2012-01-01

    A systematic design-oriented, five-step approach to material selection is described: 1) establishing design requirements, 2) material screening, 3) ranking, 4) researching specific candidates and 5) applying specific cultural constraints to the selection process. At the core of this approach is the definition performance indices (i.e., particular combinations of material properties that embody the performance of a given component) in conjunction with material property charts. These material selection charts, which plot one property against another, are introduced and shown to provide a powerful graphical environment wherein one can apply and analyze quantitative selection criteria, such as those captured in performance indices, and make trade-offs between conflicting objectives. Finding a material with a high value of these indices maximizes the performance of the component. Two specific examples pertaining to aerospace (engine blades and pressure vessels) are examined, both at room temperature and elevated temperature (where time-dependent effects are important) to demonstrate the methodology. The discussion then turns to engineered/hybrid materials and how these can be effectively tailored to fill in holes in the material property space, so as to enable innovation and increases in performance as compared to monolithic materials. Finally, a brief discussion is presented on managing the data needed for materials selection, including collection, analysis, deployment, and maintenance issues.

  13. Spectrally selective solar energy materials

    International Nuclear Information System (INIS)

    Sikkens, M.

    1981-01-01

    The performance and properties of spectrally selective materials are considered and, in particular, the selective absorption of solar radiation by free electrons is discussed, both in a homogeneous material in which these electrons are strongly scattered, and in a composite material consisting of small metal particles in a dielectric host. Such materials can be used as selective absorbers if they are deposited as a thin film onto a metal substrate, the latter providing the required low emittance. This type of selective surfaces is produced by reactive sputtering of Ni in an Ar/CH 4 gas mixture. This method can yield Ni films with a considerable carbon concentration. The carbon concentration can be varied over a wide range by adjusting the partial methane pressure. The associated experimental techniques are discussed. As the carbon concentration increases, the structure of the films changes from a Ni phase in which carbon is dissolved, via an intermediate Ni 3 C phase into an amorphous carbon phase with a high electrical resistivity in which small nickel particles are embedded. Both mechanisms of selective absorption by free electrons are observed and are found to be well described by rather simple models. The best selectivity is obtained at high carbon concentrations where the films consist of nickel particles in carbon. Depending on the film thickness and the substrate material, the solar absorptance varies between 0.78 and 0.90, while the thermal emittance varies between 0.025 and 0.04. Since the films are found to be stable at 400 0 C in vacuum, it appears that these films are good candidates for application in photothermal solar energy conversion at temperature levels around 200 0 C and higher. (Auth.)

  14. Europa Lander Material Selection Considerations

    Energy Technology Data Exchange (ETDEWEB)

    Tappan, Alexander S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Heller, Mellisa [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-01-10

    Energetic materials (EMs, explosives, pyrotechnics, propellants) provide high-power output of high temperature reaction products. These products can be solid, liquid, or gaseous during reaction or after the products have equilibrated with the surroundings. For example, high explosives typically consist of carbon, hydrogen, nitrogen, and oxygen bonded within a single molecule, and produce almost exclusively gaseous products. Conversely, intermetallics consist of physical mixtures of metals and metalloids, and produce almost exclusively condensed products. Other materials such as pyrotechnics and propellants have intermediate behavior. All energetic materials react in a self-propagating manner that after ignition, does not necessarily require energy input from the surroundings. The range of reaction velocities can range from mm/s for intermetallics, to km/s for high explosives. Energetic material selection depends on numerous requirements specific to the needs of a system. High explosives are used for applications where high pressure gases are necessary for pushing or fracturing materials (e.g., rock, metal) or creating shock waves or air blast. Propellants are used to produce moderate-pressure, high-temperature products without a shock wave. Pyrotechnics are used to produce numerous effects including: high-temperature products, gases, light, smoke, sound, and others. Thermites are used to produce heat, high-temperature products, materials, and other effects that require condensed products. Intermetallics are used to produce high-temperature condensed products and materials, with very little gas production. Numerous categories of energetic materials exist with overlapping definitions, effects, and properties.

  15. Waste package materials selection process

    International Nuclear Information System (INIS)

    Roy, A.K.; Fish, R.L.; McCright, R.D.

    1994-01-01

    The office of Civilian Radioactive Waste Management (OCRWM) of the United States Department of Energy (USDOE) is evaluating a site at Yucca Mountain in Southern Nevada to determine its suitability as a mined geologic disposal system (MGDS) for the disposal of high-level nuclear waste (HLW). The B ampersand W Fuel Company (BWFC), as a part of the Management and Operating (M ampersand O) team in support of the Yucca Mountain Site Characterization Project (YMP), is responsible for designing and developing the waste package for this potential repository. As part of this effort, Lawrence Livermore National Laboratory (LLNL) is responsible for testing materials and developing models for the materials to be used in the waste package. This paper is aimed at presenting the selection process for materials needed in fabricating the different components of the waste package

  16. Cristallini Material Review and Selection

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Nicholas [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Savina, Joseph [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Hebden, Andrew [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division

    2016-09-30

    The creation of a handheld unit to utilize the Cristallini method of uranium hexafluoride sampling requires the identification and qualification of suitable substrate materials. These materials will need to quickly and completely react with the process gas, resist vapor locking under vacuum, while being relatively inexpensive and homogeneous. Two forms of powdered alumina have been chosen for a head-to-head comparison during upcoming uranium hexafluoride tests. Both materials have shown ideal uptake characteristics during tungsten hexafluoride tests with a high loading capacity and no measureable breakthrough. They have also been shown to work well at vacuums below 10 Torr, are commercially available and inexpensive. In addition, two possible hydrogen fluoride trapping materials, sodium fluoride and saturated calcium carbonate, have been identified for further testing.

  17. Selection of materials for ETF

    International Nuclear Information System (INIS)

    Nygren, R.E.

    1980-01-01

    Repeated operation of a long burning, ignited plasma in ETF implies high exposure to an intense source of energetic particles and high energy (14.1 MeV) neutrons and presents a unique environment for materials in ETF compared with earlier tokamaks. Designing ETF (and FED) will provide many insights into reactor relevant design issues related to materials performance, particularly in components outside the first wall. This paper focuses primarily on how exposure to the plasma and radiation damage to materials infuence the design lifetime of particular components, including the first wall, armor, and TF coils. Also discussed are radiaton exposure limits for repair welding of the torus and for electrical materials used in RF and diagnostics

  18. Material selection for TFTR limiters

    International Nuclear Information System (INIS)

    Ulrickson, M.

    1980-10-01

    The requirements for the material to be used as the first surface of limiters in TFTR are that it: (1) withstand a heat flux of 1 kw/cm 2 for a pulse length of 1.5s and a duty cycle of 1/200 for 10 5 cycles, (2) withstand the thermal and electro-magnetic loads from 10 4 plasma current disruptions lasting about 200 μs, (3) generate impurities at a rate low enough to meet impurity control requirements (which depend on the atomic number of the material) for TFTR, and (4) have tritium retention characteristics consistent with tritium inventory requirements for TFTR. An extensive set of material tests using electron beams, neutral beams, and plasma bombardment have been carried out to identify materials which can meet the thermal requirements of the above

  19. Material selection and embodied energy

    CSIR Research Space (South Africa)

    Ampofo-Anti, N

    2010-11-01

    Full Text Available mix concrete apron Non reinforced, ready mix concrete strip foundation Non reinforced, ready mix ground floor slab Concrete block Modular, hollow concrete block Solid concrete block Finishes Floor screed Insulated ceiling panel Perlite... Predicting the embodied energy contribution of a single material is however not as easy as green building practices assume. As illustrated by the example in Box 1, the choice of a material implies the choice of integral constituents such as insulation...

  20. Selected advances in materials research

    International Nuclear Information System (INIS)

    Cunningham, J.E.

    1979-01-01

    Several findings emanating from materials research that should have a beneficial impact on technological advancement in the future are described. The report deals with the GRAPHNOL, a new class of high-temperature brazing alloy for joining refractory components, gel-sphere-pac process for manufacture of nuclear fuel, and noble-metal fuel cladding for service in radioisotope thermoelectric generators designed to provide auxiliary power aboard spacecraft for planetary exploration

  1. Material selection for an aerospace component

    OpenAIRE

    Jönsson, Gustav

    2015-01-01

    In the world of today there is a drive for lighter and more effective products for various reasons e.g. reduced environmental impact, higher payload, fuel efficiency etc. There is also an expanding development of new materials for a large number of different applications. This makes it more and more difficult for engineers to make good material selections. This has led to the development of a large amount of material selection methods that require more or less effort to select material. An ef...

  2. Eco-Material Selection for Auto Bodies

    Energy Technology Data Exchange (ETDEWEB)

    Mayyas, Ahmad T [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Omar, Mohammed [Masdar Institute of Science & Technology; Hayajneh, Mohammed T. [Jordan University of Science and Technology

    2017-09-25

    In the last decades, majority of automakers started to include lightweight materials in their vehicles to meet hard environmental regulations and to improve fuel efficiency of their vehicles. As a result, eco-material selection for vehicles emerged as a new discipline under design for environment. This chapter will summarize methods of eco-material selections for automotive applications with more emphasis into auto-bodies. A set of metrics for eco-material selection that takes into account all economic, environmental and social factors will be developed using numerical and qualitative methods. These metrics cover products' environmental impact, functionality and manufacturability, in addition to the economic and societal factors.

  3. Selective nanoscale growth of lattice mismatched materials

    Science.gov (United States)

    Lee, Seung-Chang; Brueck, Steven R. J.

    2017-06-20

    Exemplary embodiments provide materials and methods of forming high-quality semiconductor devices using lattice-mismatched materials. In one embodiment, a composite film including one or more substantially-single-particle-thick nanoparticle layers can be deposited over a substrate as a nanoscale selective growth mask for epitaxially growing lattice-mismatched materials over the substrate.

  4. The materials selection in ITER and the first materials workshop

    International Nuclear Information System (INIS)

    Matera, R.; Barabash, V.; Kalinin, G.; Tanaka, S.

    1998-01-01

    The selection of materials and joining technologies to be used in ITER is a trade-off between multiple and often conflicting requirements derived from the unique features of the fusion environment. Materials selection must encompass a total engineering approach, by considering not only physical and mechanical properties, but also the components' manufacturing, their maintainability and reliability, and, finally, how they can be recycled or disposed of at the end of machine operation

  5. Material and process selection using product examples

    DEFF Research Database (Denmark)

    Lenau, Torben Anker

    2001-01-01

    The objective of the paper is to suggest a different procedure for selecting materials and processes within the product development work. The procedure includes using product examples in order to increase the number of alternative materials and processes that is considered. Product examples can c...... a search engine, and through hyperlinks can relevant materials and processes be explored. Realising that designers are very sensitive to user interfaces do all descriptions of materials, processes and products include graphical descriptions, i.e. pictures or computer graphics....

  6. Material and process selection using product examples

    DEFF Research Database (Denmark)

    Lenau, Torben Anker

    2002-01-01

    The objective of the paper is to suggest a different procedure for selecting materials and processes within the product development work. The procedure includes using product examples in order to increase the number of alternative materials and processes that is considered. Product examples can c...... a search engine, and through hyperlinks can relevant materials and processes be explored. Realising that designers are very sensitive to user interfaces do all descriptions of materials, processes and products include graphical descriptions, i.e. pictures or computer graphics....

  7. Quality criteria for phase change materials selection

    International Nuclear Information System (INIS)

    Vitorino, Nuno; Abrantes, João C.C.; Frade, Jorge R.

    2016-01-01

    Highlights: • Selection criteria of phase change materials for representative applications. • Selection criteria based on reliable solutions for latent heat transfer. • Guidelines for the role of geometry and heat transfer mechanisms. • Performance maps based on PCM properties, operating conditions, size and time scales. - Abstract: Selection guidelines are primary criterion for optimization of materials for specific applications in order to meet simultaneous and often conflicting requirements. This is mostly true for technologies and products required to meet the main societal needs, such as energy. In this case, gaps between supply and demand require strategies for energy conversion and storage, including thermal storage mostly based on phase change materials. Latent heat storage is also very versatile for thermal management and thermal control by allowing high storage density within narrow temperature ranges without strict dependence between stored thermal energy and temperature. Thus, this work addressed the main issues of latent heat storage from a materials selection perspective, based on expected requirements of applications in thermal energy storage or thermal regulation. Representative solutions for the kinetics of latent heat charge/discharge were used to derive optimization guidelines for high energy density, high power, response time (from fast response to thermal inertia), etc. The corresponding property relations were presented in graphical forms for a wide variety of prospective phase change materials, and for wide ranges of operating conditions, and accounting for changes in geometry and mechanisms.

  8. Optimal materials selection for bimaterial piezoelectric microactuators

    OpenAIRE

    Srinivasan, P.; Spearing, S.M.

    2008-01-01

    Piezoelectric actuation is one of the commonly employed actuation schemes in microsystems. This paper focuses on identifying and ranking promising active material/substrate combinations for bimaterial piezoelectric (BPE) microactuators based on their performance. The mechanics of BPE structures following simple beam theory assumptions available in the literature are applied to evolve critical performance metrics which govern the materials selection process. Contours of equal performance are p...

  9. Selection of refractory materials for pyrochemical processing

    International Nuclear Information System (INIS)

    Axler, K.M.; DePoorter, G.L.; Bagaasen, L.M.

    1991-01-01

    Several pyrochemical processing operations require containment materials that exhibit minimal chemical interactions with the system, good thermal shock resistance, and reusability. One example is Direct Oxide Reduction (DOR). DOR involves the conversion of PuO 2 to metal by an oxidation/reduction reaction with Ca metal. The reaction proceeds within a molten salt flux at temperatures above 800C. A combination of thermodynamics, system thermodynamic modeling, and experimental investigations are in use to select and evaluate potential containment materials

  10. Effects of LDEF flight exposure on selected polymer matrix resin composite materials

    Science.gov (United States)

    Slemp, Wayne S.; Young, Philip R.; Witte, William G., Jr.; Shen, James Y.

    1992-01-01

    The characterization of selected graphite fiber reinforced epoxy (934 and 5208) and polysulfone (P1700) matrix resin composites materials which received over five years and nine months of exposure to the low earth orbit (LEO) environment in experiment AO134 on the Long Duration Exposure Facility is reported. The changes in mechanical properties of ultimate tensile strength and tensile modulus for exposed flight specimens are compared to the three sets of control specimens. Marked changes in surface appearance are discussed, and resin loss is reported. The chemical characterization including infrared, thermal, and selected solution property measurements showed that the molecular structure of the polymetric matrix had not changed significantly in response to this exposure.

  11. Petróleo

    OpenAIRE

    Celso Fernando Lucchesi

    1998-01-01

    COM MENOS DE 50 anos de atividade empresarialmente organizada a exploração de petróleo no Brasil encontra-se em fase de mudança com a aprovação, em 1997, da nova legislação do setor de petróleo. Descreve-se neste trabalho o período pré-Petrobras (1858 a 1953) e a exclusividade da Petrobras (1954 a 1997) que resultou no expressivo volume de reservas de petróleo no país, da ordem de 17 bilhões de barris de óleo equivalente no final de 1997. Projetos de produção já iniciados elevarão a produção ...

  12. Leo II PC

    Data.gov (United States)

    Kansas Data Access and Support Center — LEO II is a second-generation software system developed for use on the PC, which is designed to convert location references accurately between legal descriptions and...

  13. Selecting materialized views in a data warehouse

    Science.gov (United States)

    Zhou, Lijuan; Liu, Chi; Liu, Daxin

    2003-01-01

    A Data Warehouse contains lots of materialized views over the data provided by the distributed heterogeneous databases for the purpose of efficiently implementing decision-support or OLAP queries. It is important to select the right view to materialize that answer a given set of queries. In this paper, we have addressed and designed algorithm to select a set of views to materialize in order to answer the most queries under the constraint of a given space. The algorithm presented in this paper aim at making out a minimum set of views, by which we can directly respond to as many as possible user"s query requests. We use experiments to demonstrate our approach. The results show that our algorithm works better. We implemented our algorithms and a performance study of the algorithm shows that the proposed algorithm gives a less complexity and higher speeds and feasible expandability.

  14. Selection and challenges for LFR reactor materials

    Energy Technology Data Exchange (ETDEWEB)

    Weisenburger, A.; Jianu, A.; Del Giacco, M.; Fetzer, R.; Heinzel, A.; Mueller, G. [Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen (Germany). Inst. for Pulsed Power and Microwave Technology

    2013-07-01

    Nuclear energy using Fast GenIV reactors can fulfil future demands concerning CO2 free, base load capability and sustainability. One of the most promising coolants especially due to its high thermal inertia is liquid lead (Pb). Since several years researches all over the world investigate this coolant and its impact on the reactor design and by that on the materials to be selected. The LEADER project, a follow up of ELSY, aims to design a prototypical demonstrator ALFRED and to continue with several design related aspects of the ELFR reactor. For a demonstrator the criteria of material selection are somewhat different to a commercial type like the ELFR. Material selection for ELFR of course considers all the aspects relevant for ALFRED plus the targeted burn up and the expected total dpa related damage especially of the fuel pins. In the past compatibility of structural material (steels like 316L, T91 and 15-15Ti (1.4970)) that can be employed for Pb cooled fast nuclear reactors were investigated in several EU projects like EUROTRANS and worldwide. Solubility of steel alloying elements like Ni, Fe, Cr is the driving force for the reduced corrosion resistance in contact with Pb. In-situ oxidation is the acknowledged measure to protect steels in Pb up to certain temperatures that are material dependent. Based on experiments and the derived temperature limits the average core outlet temperatures of ALFRED and the ELFR are set to 480 C. The most challenging conditions with respect to temperature are at the fuel assembly and the heat exchangers. For both, thin stable oxide scales with negligible reduction in heat transfer are the requested protection method. This presentation will give an overview on the selected materials for ALFRED and ELFR considering, beside pure compatibility, the influence of mechanical interaction like creep and fretting. (orig.)

  15. Selection of plasma facing materials for ITER

    International Nuclear Information System (INIS)

    Ulrickson, M.; Barabash, V.; Chiocchio, S.

    1996-01-01

    ITER will be the first tokamak having long pulse operation using deuterium-tritium fuel. The problem of designing heat removal structures for steady state in a neutron environment is a major technical goal for the ITER Engineering Design Activity (EDA). The steady state heat flux specified for divertor components is 5 MW/m 2 for normal operation with transients to 15 MW/m 2 for up to 10 s. The selection of materials for plasma facing components is one of the major research activities. Three materials are being considered for the divertor; carbon fiber composites, beryllium, and tungsten. This paper discusses the relative advantages and disadvantages of these materials. The final section of plasma facing materials for the ITER divertor will not be made until the end of the EDA

  16. Material selection for design, manufacturing and application

    International Nuclear Information System (INIS)

    Zaid, A.I.O.

    2011-01-01

    Developing a new engineering material product or changing an existing one requires new design selecting material and choosing appropriate and economical manufacturing processes. These three main factors play a great role on the performance of the product in service. These items are independent and should not be performed in isolation from each other. With the great advancement of technology in the last decade and with the greater number of engineering materials which are now available, together with the increasing pressure to produce more economic and get reliable products an integrated approach which considers design, material selection and the appropriate manufacturing process makes it easier to achieve the optimum product that combines the functional requirements with the reliability at competitive cost. These diverse activities or items are interdependent; therefore should not be considered in isolation from each other, for example, it is not sufficient that design of the product should satisfy the technical, safety and legal requirements, it must also be possible to be manufactured economically and to be sold at a competitive price and easily disposed at the end of its working life cycle. In this paper, the interaction of these items together in order to arrive to the optimum solution for a particular application are given and discussed. (author)

  17. Portfolio theory in the selection of oil investment projects Teoria de carteiras na seleção de projetos de investimento em petróleo

    Directory of Open Access Journals (Sweden)

    Jalimar Guimarães Simplício

    2012-01-01

    Full Text Available The objective of this article is to compare investment project selection using the efficient frontier in the mean-variance space based on optimization models introduced by Markowitz (1952 with the project ranking method according to the profitability index (PI. The selection of real assets by companies did not incorporate the mean-variance optimization procedure in the same way the selection of financial assets in investment portfolios did. The process of selection and formation of portfolios of investment projects for the oil area of a company in the energy industry was analyzed. Project portfolios formed according to the usual company practice of ranking by their PI were compared with those that result from applying mean-variance optimization through Monte Carlo simulation, which allows the computation of mean returns, variances, and covariances for the set of projects considered. The inefficiency of project portfolios obtained by ranking according to the PI compared to those obtained by the method of Markowitz suggests that there are opportunities to improve the process of selecting the set of projects to be implemented by companies.O objetivo deste artigo é comparar a seleção de projetos de investimento segundo a fronteira eficiente no espaço média-variância com base em modelos de otimização introduzidos por Markowitz (1952 com o método do ordenamento de projetos segundo o índice de lucratividade (IL. A seleção de ativos reais pelas empresas não incorporou o procedimento de otimização de média-variância da mesma forma que na seleção de ativos financeiros para carteiras de investimento. O processo de seleção e formação de carteiras de projetos de investimento pela área de petróleo de uma empresa do setor de energia foi analisado. Carteiras de projetos constituídas de acordo com a prática usual da empresa de ordenamento pelo IL foram comparadas com as que resultariam da aplicação da otimização de m

  18. Degradation of Silicon Carbide Reflective Surfaces in the LEO Environment

    Science.gov (United States)

    Mileti, Sandro; Coluzzi, Plinio; Marchetti, Mario

    2009-01-01

    Space mirrors in Low Earth Orbit (LEO) encounter a degradation problem caused by the impact of atomic oxygen (ATOX) in the space environment. This paper presents an experiment of the atomic oxygen impact degradation and UV synergic effects on ground simulation. The experiment was carried out in a dedicated ATOX simulation vacuum chamber. As target materials, a polished CVD Beta-silicon carbide (SiC) coating was investigated. The selection of silicon carbide is due to its high potential candidate as a mirror layer substrate material for its good reflectance at UV wavelengths and excellent thermal diffusivity. It has highly desirable mechanical and thermal properties and can achieve an excellent surface finish. The deposition of the coatings were on carbon-based material substrate; i.e., silicon impregnated carbon fiber composite (C/SiC). Mechanical and thermal properties of the coatings such as hardness and Coefficient of Thermal Expansion (CTE) were achieved. Several atomic oxygen impact angles were studied tilting the target samples respect to the flux direction. The various impact angles permitted to analyze the different erosion rates and typologies which the mirrors would encounter in LEO environment. The degradation was analyzed in various aspects. Macroscopic mass loss per unit area, surface roughness and morphology change were basically analyzed. The exposed surfaces of the materials were observed through a Scanning Electron Microscope (SEM). Secondly, optical diagnostic of the surfaces were performed in order to investigate their variation in optical properties as the evaluation of reflectance degradation. The presence of micro-cracks caused by shrinkage, grinding, polishing or thermal cycling and the porosity in the coatings, could have led to the undercutting phenomenon. Observation of uprising of undercutting was also conducted. Remarks are given regarding capabilities in short-term mission exposures to the LEO environment of this coating.

  19. Emission of particulate matter from ternary blends consisting of biodiesel, ethanol and vegetable oil: a comparison with conventional dieselEmissão de material particulado por misturas ternárias compostas de biodiesel, etanol e óleo vegetal: uma comparação com o óleo diesel convencional

    Directory of Open Access Journals (Sweden)

    Murilo Daniel de Melo Innocentini

    2011-12-01

    Full Text Available The purpose of this study was to quantify the particulate matter emission from ternary blends comprehending biodiesel, ethanol and vegetable oil in a Diesel cycle engine, and an identical engine working with petrol diesel as control. To compare the fuels’ emissions, the particulate matter from the engine’s exhaust was collected, using a fiberglass circular filter paper, which was coupled by means of a steel flange at the end of the exhaust pipe. The results with ternary blends showed expressive reduction of particulate matter level exhausted by the engine, in its maximum load. We can conclude that the utilization of ternary blends, with the methods and conditions of this experiment, was efficient to reduce the emission of particulate matter contained in the exhaust gases of Diesel cycle engine.O objetivo deste trabalho foi quantificar a emissão de material particulado de misturas ternárias compostas de biodiesel, etanol e óleo vegetal em um motor de ciclo Diesel, tendo como testemunha um motor idêntico funcionando com óleo diesel de petróleo. Para a comparação da emissão dos dois combustíveis, foi realizada a coleta de material particulado proveniente dos escapamentos dos motores com um filtro circular confeccionado de fibra de vidro, que foi acoplado com um flange de aço, no final da tubulação de escape. Os resultados obtidos com a utilização das misturas ternárias de biocombustíveis indicaram uma redução expressiva no nível de material particulado emitido pelo motor em sua carga máxima. Pode-se concluir que a utilização das misturas ternárias, nas condições e métodos de realização do experimento, foi eficiente na redução de emissão de material particulado presente nos gases de exaustão do motor de ciclo Diesel.

  20. O óleo de abacate (Persea americana Mill como matéria-prima para a indústria alimentícia The avocado oil (Persea americana Mill as a raw material for the food industry

    Directory of Open Access Journals (Sweden)

    Jocelem Mastrodi Salgado

    2008-12-01

    Full Text Available Hábitos de vida saudáveis e uma dieta balanceada aliados ao alto consumo de frutas e vegetais estão associados à redução do risco de doenças e à manutenção da saúde. O óleo de abacate possui em sua composição substâncias bioativas capazes de prevenir e controlar as dislipidemias. Como existem poucas pesquisas científicas avaliando o potencial deste óleo para o consumo humano, o presente trabalho estudou os processos de extração e refino do óleo de abacate. Para tanto, procedeu-se à separação da polpa das outras partes da fruta. A polpa fresca foi seca em estufa, e posteriormente moída para a obtenção de um farelo. O óleo obtido do farelo foi extraído e caracterizado. Os resultados mostraram que os processos de extração e refino do óleo a partir da variedade Margarida são tecnicamente viáveis, o que o torna excelente matéria-prima para a indústria alimentícia. Além disso, possui um perfil de ácidos graxos e esteróis muito semelhante ao perfil do azeite de oliva, podendo desta forma, substituir o óleo de soja e ser utilizado juntamente com o azeite de oliva nos óleos mistos, oferecendo ao consumidor brasileiro um produto de qualidade superior e com menor custo.Healthy life habits and an adequate diet, together with a high intake of fruits and vegetables, are associated with reducing the risk of diseases and maintaining health. The avocado oil has bioactive substances that can prevent and control the hyperlipidemia. Since there is little scientific research evaluating the oil potential for human consumption, the present work studied the extraction and refining process of the avocado oil. Firstly, the pulp was extracted from the fruit. The fresh pulp was dried in a stove and then grounded for obtaining the bran. The oil obtained from de bran was extracted and characterized. The results showed that the extraction and refining process of the Margarida avocado variety is technically feasible, and it is an

  1. Selection, development and characterisation of plasma facing materials for ITER

    International Nuclear Information System (INIS)

    Barabash, V.; Akiba, M.; Ulrickson, M.; Vieider, G.

    1996-01-01

    The current status of the selection of the armour materials for first wall, limiters and divertor are presented. The candidate armour materials are beryllium, tungsten and carbon base materials (mainly carbon fiber composites). The selection of the references grades from these material classes is discussed and the candidate grades are described. The main reasons for the selection of the reference grades are also discussed. The urgent materials R and D needs for the development of the design are described briefly. (orig.)

  2. Tools for Material Design and Selection

    Science.gov (United States)

    Wehage, Kristopher

    The present thesis focuses on applications of numerical methods to create tools for material characterization, design and selection. The tools generated in this work incorporate a variety of programming concepts, from digital image analysis, geometry, optimization, and parallel programming to data-mining, databases and web design. The first portion of the thesis focuses on methods for characterizing clustering in bimodal 5083 Aluminum alloys created by cryomilling and powder metallurgy. The bimodal samples analyzed in the present work contain a mixture of a coarse grain phase, with a grain size on the order of several microns, and an ultra-fine grain phase, with a grain size on the order of 200 nm. The mixing of the two phases is not homogeneous and clustering is observed. To investigate clustering in these bimodal materials, various microstructures were created experimentally by conventional cryomilling, Hot Isostatic Pressing (HIP), Extrusion, Dual-Mode Dynamic Forging (DMDF) and a new 'Gradient' cryomilling process. Two techniques for quantitative clustering analysis are presented, formulated and implemented. The first technique, the Area Disorder function, provides a metric of the quality of coarse grain dispersion in an ultra-fine grain matrix and the second technique, the Two-Point Correlation function, provides a metric of long and short range spatial arrangements of the two phases, as well as an indication of the mean feature size in any direction. The two techniques are implemented on digital images created by Scanning Electron Microscopy (SEM) and Electron Backscatter Detection (EBSD) of the microstructures. To investigate structure--property relationships through modeling and simulation, strategies for generating synthetic microstructures are discussed and a computer program that generates randomized microstructures with desired configurations of clustering described by the Area Disorder Function is formulated and presented. In the computer program, two

  3. Seleção de concretos refratários densos antierosivos para unidades de craqueamento catalítico fluidizado de petróleo Selection of dense antierosive refractory castables for fluid catalytic cracking units

    Directory of Open Access Journals (Sweden)

    F. A. S. Serra

    2012-03-01

    Full Text Available Na indústria petroquímica a unidade de craqueamento catalítico fluidizado de petróleo é um importante equipamento para aplicação de concretos refratários devido à necessidade de se obter produtos especializados. Normalmente, a seleção destes materiais é baseada na análise química e em medidas de densidade aparente, resistência mecânica por compressão uniaxial e erosimetria a frio. Para avaliação dos requisitos de seleção usuais, cinco concretos de alta alumina, sendo três de baixo teor de cimento e dois convencionais de uso comercial, foram avaliados por resistência à compressão e erosimetria a frio. Testes complementares que atualmente não são utilizados no processo de seleção também foram realizados, tais como: resistência ao choque térmico, módulo de ruptura a quente e exposição em atmosfera de CO. A análise mostrou que as especificações vigentes são baseadas principalmente na experiência com a utilização de produtos não originalmente projetados para esta aplicação e que o desenvolvimento de produtos mais adequados é inibido pelas restrições das especificações atuais. Também se verificou que a seleção é limitada pela falta de ensaios que avaliem o desempenho em condições mais próximas das de uso. Neste sentido, o teste de resistência à deposição de carbono pela exposição em atmosfera de CO mostrou-se interessante por contribuir para uma melhor seleção dos concretos refratários densos antierosivos.In the petrochemical industry the fluidized catalytic cracking unit is an important vessel for refractory castables application due the necessity of obtaining specialized products. Usually, the selection of these materials is based on the chemical analysis, apparent density, cold crushing strength and cold erosion test. For the evaluation of the present selection requirements, five high-alumina castables, being three of low cement and two conventional of commercial use, were

  4. Petróleo

    Directory of Open Access Journals (Sweden)

    Celso Fernando Lucchesi

    1998-08-01

    Full Text Available COM MENOS DE 50 anos de atividade empresarialmente organizada a exploração de petróleo no Brasil encontra-se em fase de mudança com a aprovação, em 1997, da nova legislação do setor de petróleo. Descreve-se neste trabalho o período pré-Petrobras (1858 a 1953 e a exclusividade da Petrobras (1954 a 1997 que resultou no expressivo volume de reservas de petróleo no país, da ordem de 17 bilhões de barris de óleo equivalente no final de 1997. Projetos de produção já iniciados elevarão a produção a mais de 1,5 milhão de barris de óleo por dia no início do novo século. O gás natural crescerá rapidamente sua participação na matriz energética a partir de 1999. Com a instalação da Agência Nacional de Petróleo (ANP inicia-se uma nova fase, sendo esta responsável pela atração de novos investimentos na busca de novas reservas nas bacias sedimentares brasileiras, cujo potencial é ainda significativo. Diversas empresas internacionais deverão estar operando no país no curto prazo, inicialmente associadas à Petrobras. O modelo adotado para as atividades de exploração e produção no país é o de concessão. A atividade no Brasil nesta área dependerá do regime fiscal que vier a ser implantado.THE APPROVAL OF the new Petroleum Law in 1997 proposed a dramatic change in the activities of petroleum exploration in Brazil after almost fifty years of its initial entrepreneurual organization, represented by the creation of Petrobras, in 1953. In this work two important periods are described: the pre-Petrobras period (1858 to 1953 and the period when Petrobras acted alone in the oil business (1954 to 1997. During the last one, significant results were achieved. The amount of reserves reached 17 billion barrels of oil equivalent and were made available to the country at the end of 1997. Production projects already in place or under development will raise Brazilian daily production to levels of 1.5 million barrels of oil per day

  5. ARTIFICIAL NEURAL NETWORKS BASED GEARS MATERIAL SELECTION HYBRID INTELLIGENT SYSTEM

    Institute of Scientific and Technical Information of China (English)

    X.C. Li; W.X. Zhu; G. Chen; D.S. Mei; J. Zhang; K.M. Chen

    2003-01-01

    An artificial neural networks(ANNs) based gear material selection hybrid intelligent system is established by analyzing the individual advantages and weakness of expert system (ES) and ANNs and the applications in material select of them. The system mainly consists of tow parts: ES and ANNs. By being trained with much data samples,the back propagation (BP) ANN gets the knowledge of gear materials selection, and is able to inference according to user input. The system realizes the complementing of ANNs and ES. Using this system, engineers without materials selection experience can conveniently deal with gear materials selection.

  6. Otimização de alternativas para o desenvolvimento de campos de petróleo Selection of alternatives for the development of oil fields

    Directory of Open Access Journals (Sweden)

    Luciana Faletti Almeida

    2007-12-01

    Full Text Available Este artigo apresenta um sistema de suporte à decisão para a otimização de alternativas de desenvolvimento de campos de petróleo. O desenvolvimento de um campo de petróleo consiste na escolha de uma alternativa para a explotação de um reservatório petrolífero, conhecido e delimitado, que permita produzir a maior quantidade de hidrocarboneto possível, dentro dos limites físicos e econômicos existentes, isto é, maximizar o valor presente líquido (VPL. O VPL é calculado a partir da produção de óleo, a qual é obtida com o uso de um simulador de reservatório. Cada execução do simulador pode demorar desde alguns segundos até várias horas, dependendo da complexidade do reservatório modelado. Isto reduz o número de alternativas que podem ser geradas e avaliadas pelo especialista na busca da melhor solução. Deste modo, o objetivo deste trabalho é propor e avaliar um sistema inteligente de otimização que emprega: algoritmos genéticos (AGs, algoritmos culturais (ACs e coevolução para a busca de uma alternativa de desenvolvimento ótima; e um ambiente de computação paralela para a simulação de reservatório e cálculo do VPL das alternativas. O sistema resultante permite que o especialista obtenha, em tempo hábil, a alternativa ótima (ou quase-ótima para o desenvolvimento de um campo de petróleo conhecido. Os resultados obtidos nos estudos de casos apresentados demonstram que o sistema proposto, baseado em técnicas inteligentes, obtém boas alternativas de desenvolvimento de campos petrolíferos com uma grande redução do tempo computacional, redução esta obtida a partir do aproveitamento do poder computacional de um ambiente de computação paralela e do aproveitamento de conhecimento do especialista, por meio das sementes iniciais.This paper presents an optimization system for the development of petroleum fields. Developing a petroleum field consists of choosing an alternative exploitation of an already known

  7. Selection of nuclear reactor coolant materials

    International Nuclear Information System (INIS)

    Shi Lisheng; Wang Bairong

    2012-01-01

    Nuclear material is nuclear material or materials used in nuclear industry, the general term, it is the material basis for the construction of nuclear power, but also a leader in nuclear energy development, the two interdependent and mutually reinforcing. At the same time, nuclear materials research, development and application of the depth and breadth of science and technology reflects a nation and the level of the nuclear power industry. Coolant also known as heat-carrier agent, is an important part of the heart nuclear reactor, its role is to secure as much as possible to the economic output in the form fission energy to heat the reactor to be used: the same time cooling the core, is controlled by the various structural components allowable temperature. This paper described the definition of nuclear reactor coolant and characteristics, and then addressed the requirements of the coolant material, and finally were introduced several useful properties of the coolant and chemical control. (authors)

  8. First-wall/blanket materials selection for STARFIRE tokamak reactor

    International Nuclear Information System (INIS)

    Smith, D.L.; Mattas, R.F.; Clemmer, R.G.; Davis, J.W.

    1980-01-01

    The development of the reference STARFIRE first-wall/blanket design involved numerous trade-offs in the materials selection process for the breeding material, coolant structure, neutron multiplier, and reflector. The major parameters and properties that impact materials selection and design criteria are reviewed

  9. Radioactive waste - a select list of material

    International Nuclear Information System (INIS)

    Lambert, C.M.

    1982-01-01

    A chronological bibliography is presented of literature relating to radioactive waste management in the United Kingdom concentrating on material published since 1978. The main sections include Dept. of Environ. and Official publications, administrative and environmental concerns, technological and scientific considerations, including publications on geological aspects, deep-sea bed and ocean-dumping and salt domes, with general background material and further sources of information listed at the end. (U.K.)

  10. Material Selection for a Manual Winch Rope Drum

    OpenAIRE

    Moses F. Oduori; Enoch K. Musyoka; Thomas O. Mbuya

    2016-01-01

    The selection of materials is an essential task in mechanical design processes. This paper sets out to demonstrate the application of analytical decision making during mechanical design and, particularly, in selecting a suitable material for a given application. Equations for the mechanical design of a manual winch rope drum are used to derive quantitative material performance indicators, which are then used in a multiple attribute decision making (MADM) model to rank the candidate materials....

  11. Selecting suitable enclosures for digitally printed materials

    International Nuclear Information System (INIS)

    Burge, D; Rima, L

    2010-01-01

    It cannot be assumed that storage enclosures considered safe for traditionally printed images and documents are suitable for modern, digitally printed materials. In this project, a large variety of digital print types were tested using a modified version of the ISO 18916 Imaging materials-Processed imaging materials-Photographic activity test for enclosure materials standard to assess the risk to digital prints by paper enclosures known to be inert or reactive with traditional photographic prints. The types of enclosures tested included buffered and non-buffered cotton papers, and groundwood paper. In addition, qualitative filter paper that had been wetted and dried with either an acidic or basic solution was also tested to determine the effects of enclosure pH on digitally printed materials. It was determined that, in general, digital prints tended to be less reactive with various enclosure types than traditional prints. Digital prints were most sensitive to paper that contained groundwood. The enclosure reactivity test results were then integrated with previous published work on the tendencies of various enclosure types to abrade, ferrotype, or block to digital prints in order to create a comprehensive set of recommendations for digital print storage enclosures.

  12. Do lions Panthera leo actively select prey or do prey preferences simply reflect chance responses via evolutionary adaptations to optimal foraging?

    Directory of Open Access Journals (Sweden)

    Matt W Hayward

    Full Text Available Research on coursing predators has revealed that actions throughout the predatory behavioral sequence (using encounter rate, hunting rate, and kill rate as proxy measures of decisions drive observed prey preferences. We tested whether similar actions drive the observed prey preferences of a stalking predator, the African lion Panthera leo. We conducted two 96 hour, continuous follows of lions in Addo Elephant National Park seasonally from December 2003 until November 2005 (16 follows, and compared prey encounter rate with prey abundance, hunt rate with prey encounter rate, and kill rate with prey hunt rate for the major prey species in Addo using Jacobs' electivity index. We found that lions encountered preferred prey species far more frequently than expected based on their abundance, and they hunted these species more frequently than expected based on this higher encounter rate. Lions responded variably to non-preferred and avoided prey species throughout the predatory sequence, although they hunted avoided prey far less frequently than expected based on the number of encounters of them. We conclude that actions of lions throughout the predatory behavioural sequence, but particularly early on, drive the prey preferences that have been documented for this species. Once a hunt is initiated, evolutionary adaptations to the predator-prey interactions drive hunting success.

  13. Do lions Panthera leo actively select prey or do prey preferences simply reflect chance responses via evolutionary adaptations to optimal foraging?

    Science.gov (United States)

    Hayward, Matt W; Hayward, Gina J; Tambling, Craig J; Kerley, Graham I H

    2011-01-01

    Research on coursing predators has revealed that actions throughout the predatory behavioral sequence (using encounter rate, hunting rate, and kill rate as proxy measures of decisions) drive observed prey preferences. We tested whether similar actions drive the observed prey preferences of a stalking predator, the African lion Panthera leo. We conducted two 96 hour, continuous follows of lions in Addo Elephant National Park seasonally from December 2003 until November 2005 (16 follows), and compared prey encounter rate with prey abundance, hunt rate with prey encounter rate, and kill rate with prey hunt rate for the major prey species in Addo using Jacobs' electivity index. We found that lions encountered preferred prey species far more frequently than expected based on their abundance, and they hunted these species more frequently than expected based on this higher encounter rate. Lions responded variably to non-preferred and avoided prey species throughout the predatory sequence, although they hunted avoided prey far less frequently than expected based on the number of encounters of them. We conclude that actions of lions throughout the predatory behavioural sequence, but particularly early on, drive the prey preferences that have been documented for this species. Once a hunt is initiated, evolutionary adaptations to the predator-prey interactions drive hunting success.

  14. SELECTED INSTRUCTIONAL MATERIALS FOR DISTRIBUTIVE EDUCATION.

    Science.gov (United States)

    LEVENDOWSKI, J.C.

    CITATIONS SUPPLEMENTING BULLETIN NO. 5, "DISTRIBUTIVE EDUCATION LIBRARY LIST," (ED 012 778) WERE SELECTED FOR DISTRIBUTIVE TEACHER EDUCATORS, ADULT INSTRUCTORS AND TEACHER COORDINATORS. THE PUBLICATIONS ARE FREE OR INEXPENSIVE BROCHURES, BULLETINS, PAMPHLETS AND PAPERBACK BOOKS, LISTED BY TOPICS--(1) "ADVERTISING AND DISPLAY," (2) "DISTRIBUTIVE…

  15. Sustainable material selection for construction industry

    DEFF Research Database (Denmark)

    Govindan, Kannan; Shankar, Madan; Kannan, Devika

    2016-01-01

    a hybrid multi criteria decision making (MCDM) methodology with a specific examination of the UAE. The indicators collected from existing literatures were used in evaluation of sustainable construction materials with the assistance of construction sector-based respondents. The proposed framework...

  16. Skin Cancer Education Materials: Selected Annotations.

    Science.gov (United States)

    National Cancer Inst. (NIH), Bethesda, MD.

    This annotated bibliography presents 85 entries on a variety of approaches to cancer education. The entries are grouped under three broad headings, two of which contain smaller sub-divisions. The first heading, Public Education, contains prevention and general information, and non-print materials. The second heading, Professional Education,…

  17. Implications of material selection on the design of packaging machinery.

    Science.gov (United States)

    Merritt, J P

    2009-01-01

    Material selection has significant implications on the design and cost of horizontal-form-fill-seal packaging machinery. To avoid excessive costs, machine redesigns and project delays, material selection must be reconciled early in the project and revisited throughout the construction of the machine.

  18. ABOUT INDEX EVALUATION OF MATERIAL RESOURCE SUPPLIER SELECTION

    OpenAIRE

    V. A. Skochinskaya

    2008-01-01

    The paper analyzes existing methods for evaluation of material resource supplier selection. It shows advantages and shortcomings of the present evaluation systems. The necessity for application of an index evaluation is justified in the paper. The paper contains rating (index) evaluation for material resource supplier selection which is based on the application of quantitative (index) tool instead of an expert (numerical) evaluation. 

  19. Raw material selection for object construction

    CSIR Research Space (South Africa)

    Perlow, J

    2017-11-01

    Full Text Available on their visual appearance. In particular, we present a method for an agent to recognise the required unseen raw material images and link them to corresponding novel object images. This capability provides an agent with an increased degree of resourcefulness... construction from component parts, and in doing so we provide a benchmark for future work to compare against within Minecraft and ShapeNet domains. II. BACKGROUND Our model is inspired by Siamese neural networks, a class of neural network that includes multiple...

  20. Basic Thermal Parameters of Selected Foods and Food Raw Materials

    OpenAIRE

    Monika Božiková; Ľubomír Híreš; Michal Valach; Martin Malínek; Jan Mareček

    2017-01-01

    In general, processing and manipulation with foods and food raw materials have significant influence on their physical properties. The article is focused on thermophysical parameters measurement of selected foods and food raw materials. There were examined thermal conductivity and thermal diffusivity of selected materials. For detection of thermal parameters was used instrument Isomet 2104, which principle of measurement is based on transient methods. In text are presented summary results of ...

  1. The Selection of Bridge Materials Utilizing the Analytical Hierarchy Process

    Science.gov (United States)

    Robert L. Smith; Robert J. Bush; Daniel L. Schmoldt

    1997-01-01

    Effective decisions on the use of natural resources often require the input of many individuals. Determining how specific criteria affect the selection of materials can lead to better utilization of raw materials. Concrete, steel, and timber represent over 98% of the materials used for bridge construction in the United States. Highway officials must often consider...

  2. Criteria for the selection of PEC primary circuit structural material

    International Nuclear Information System (INIS)

    Antoni, R.; Brunori, G.; Maesa, S.; Scibona, G.; Tomassetti, G.

    1977-01-01

    The choice of the structural materials is generally a compromise between the project requirements, the characteristics (mechanical and environmental) of the materials and the available technology to construct the various parts of the components. The criteria of selection of structural materials for the primary circuit of fast reactor are reported. The criteria concern both general and utilization aspects

  3. Surface analysis of selected hydrophobic materials

    Science.gov (United States)

    Wisniewska, Sylwia Katarzyna

    This dissertation contains a series of studies on hydrophobic surfaces by various surface sensitive techniques such as contact angle measurements, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and atomic force microscopy (AFM). Hydrophobic surfaces have been classified as mineral surfaces, organic synthetic surfaces, or natural biological surfaces. As a model hydrophobic mineral surface, elemental sulfur has been selected. The sulfur surface has been characterized for selected allotropic forms of sulfur such as rhombic, monoclinic, plastic, and cyclohexasulfur. Additionally, dextrin adsorption at the sulfur surface was measured. The structure of a dextrin molecule showing hydrophobic sites has been presented to support the proposed hydrophobic bonding nature of dextrin adsorption at the sulfur surface. As a model organic hydrophobic surface, primary fatty amines such as dodecylamine, hexadecylamine, and octadecylamine were chosen. An increase of hydrophobicity, significant changes of infrared bands, and surface topographical changes with time were observed for each amine. Based on the results it was concluded that hydrocarbon chain rearrangement associated with recrystallization took place at the surface during contact with air. A barley straw surface was selected as a model of biological hydrophobic surfaces. The differences in the contact angles for various straw surfaces were explained by the presence of a wax layer. SEM images confirmed the heterogeneity and complexity of the wax crystal structure. AFM measurements provided additional structural details including a measure of surface roughness. Additionally, straw degradation as a result of conditioning in an aqueous environment was studied. Significant contact angle changes were observed as soon as one day after conditioning. FTIR studies showed a gradual wax layer removal due to straw surface decomposition. SEM and AFM images revealed topographical changes and biological

  4. Chemical composition and antimicrobial activity of essential oils from selected herbs cultivated in the South of Brazil against food spoilage and foodborne pathogens Composição química e atividade antimicrobiana de óleos essenciais de plantas selecionadas cultivadas no Sul do Brasil contra micro-organismos patogênicos e deteriorantes de alimentos

    Directory of Open Access Journals (Sweden)

    Sheila Mello da Silveira

    2012-07-01

    Full Text Available The chemical composition of 10 selected plant essential oils obtained by steam distillation was determined by GC and GC/MS. The antimicrobial activity of the essential oils was screened against 12 important food-related bacterial strains by agar disc-diffusion assay. MIC and MBC were determined for the essential oils that presented the highest activity in the agar disc-diffusion test. The most active essential oils against the tested bacteria were, in descending order, lemongrass (Cymbopogon flexuosus, basil (Ocimum basilicum, oregano (Origanum vulgare, cinnamon leaf (Cinnamomum zeylanicum, and laurel (Laurus nobilis. Except for S. Typhimurium, the tested bateria were inhibited at MIC values lower or equal to 0.62mg mL-1 by lemongrass (Cymbopogon flexuosus essential oil. Yersinia enterocolitica presented the highest sensitivity to all essential oils tested (CMI≤0.62mg mL-1. There was a significant correlation (PA composição química de 10 óleos essenciais obtidos por destilação a vapor foi determinada por CG/DIC e CG/EM. A atividade antimicrobiana dos óleos essenciais foi detectada através do método de difusão em ágar frente a 12 espécies de bactérias de importância em alimentos. As CMI e CMB foram determinadas para os óleos essenciais que na difusão em ágar evidenciaram maior atividade. Os óleos essenciais que apresentaram maior atividade contra as bactérias testadas foram, em ordem decrescente, os de capim-limão (Cymbopogon flexuosus, manjericão (Ocimum basilicum, orégano (Origanum vulgare, folha de canela (Cinnamomum zeylanicum e louro (Laurus nobilis. Com exceção de S. Typhimurium, o óleo essencial de capim limão (Cymbopogon flexuosus apresentou valores de CMI e CMB iguais ou inferiores a 0,62mg mL-1 contra os micro-organismos testados. Yersinia enterocolitica foi o patógeno mais sensível frente a todos os óleos essenciais avaliados (CMI≤0,62mg mL-1. Foi detectada correlação significativa (P<0,05 entre os n

  5. Sorption analyses in materials science: selected oxides

    International Nuclear Information System (INIS)

    Fuller, E.L. Jr.; Condon, J.B.; Eager, M.H.; Jones, L.L.

    1981-01-01

    Physical adsorption studies have been shown to be extremely valuable in studying the chemistry and structure of dispersed materials. Many processes rely on the access to the large amount of surface made available by the high degree of dispersion. Conversely, there are many applications where consolidation of the dispersed solids is required. Several systems (silica gel, alumina catalysts, mineralogic alumino-silicates, and yttrium oxide plasters) have been studied to show the type and amount of chemical and structural information that can be obtained. Some review of current theories is given and additional concepts are developed based on statistical and thermodynamic arguments. The results are applied to sorption data to show that detailed sorption analyses are extremely useful and can provide valuable information that is difficult to obtain by any other means. Considerable emphasis has been placed on data analyses and interpretation of a nonclassical nature to show the potential of such studies that is often not recognized nor utilized

  6. Subsurface material identification and sensor selection

    Science.gov (United States)

    T, H.; Reghunadh, R.; Ramesh, M. V.

    2017-12-01

    In India, most of the landslides occur during monsoon season and causes huge loss of life and property. Design of an early warning system for highly landslide prone area will reduce losses to a great extent. The in-situ monitoring systems needs deployment of several sensors inside a borehole for monitoring a particular slope. Amrita Center for Wireless Networks and Applications (AmritaWNA), Amrita University has designed, developed and deployed a Wireless Sensor Network (WSN) for real time landslide monitoring using geotechnical instruments and sensors like rain gauge, moisture sensor, piezometer, strain gauge, tilt meter and geophone inside a Deep Earth Probe (DEP) at different locations. These sensors provide point measurements of the subsurface at a higher accuracy. Every landslide prone terrain is unique with respect to its geology, hydrological conditions, meteorological conditions, velocity of movement etc. The decision of installing different geotechnical instruments in a landslide prone terrain is a crucial step to be considered. Rain gauge, moisture sensor, and piezometer are usually used in clay rich areas to sense the moisture and pore pressure values. Geophone and Crack meter are instruments used in rocky areas to monitor cracks and vibrations associated with a movement. Inclinometer and Strain gauge are usually placed inside a casing and can be used in both rocky and soil areas. In order to place geotechnical instruments and sensors at appropriate places Electrical Resistivity Tomography (ERT) method can be used. Variation in electrical resistivity values indicate the changes in composition, layer thickness, or contaminant levels. The derived true resistivity image can be used for identifying the type of materials present in the subsurface at different depths. We have used this method for identifying the type of materials present in our site at Chandmari (Sikkim). Fig 1 shows the typical resistivity values of a particular area in Chandmari site. The

  7. Material Selection for Accident Tolerant Fuel Cladding

    International Nuclear Information System (INIS)

    Pint, Bruce A.; Terrani, Kurt A.; Yamamoto, Yukinori; Snead, Lance Lewis

    2015-01-01

    Alternative cladding materials to Zr-based alloys are being investigated for accident tolerance, which can be defined as > 100X improvement (compared to Zr-based alloys) in oxidation resistance to steam or steam-H 2 environments at ≥1473 K (1200°C) for short times. After reviewing a wide range of candidates, current steam oxidation testing is being conducted on Mo, MAX phases and FeCrAl alloys. Recently reported low mass losses for Mo in steam at 800°C could not be reproduced. Both FeCrAl and MAX phase Ti 2 AlC form a protective alumina scale in steam. However, commercial Ti 2 AlC that was not single phase, formed a much thicker oxide at 1200°C in steam and significant TiO 2 , and therefore Ti 2 AlC may be challenging to form as a cladding or a coating. Alloy development for FeCrAl is seeking to maintain its steam oxidation resistance to 1475°C, while reducing its Cr content to minimize susceptibility to irradiation-assisted α' formation. The composition effects and critical limits to retaining protective scale formation at > 1400°C are still being evaluated.

  8. Material Selection for Accident Tolerant Fuel Cladding

    Energy Technology Data Exchange (ETDEWEB)

    Pint, Bruce A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Terrani, Kurt A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Yamamoto, Yukinori [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Snead, Lance Lewis [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-01-01

    Alternative cladding materials to Zr-based alloys are being investigated for accident tolerance, which can be defined as > 100X improvement (compared to Zr-based alloys) in oxidation resistance to steam or steam-H2 environments at ≥ 1200°C for short times. After reviewing a wide range of candidates, current steam oxidation testing is being conducted on Mo, MAX phases and FeCrAl alloys. Recently reported low mass losses for Mo in steam at 800°C could not be reproduced. Both FeCrAl and MAX phase Ti2AlC form a protective alumina scale in steam. However, commercial Ti2AlC that was not single phase, formed a much thicker oxide at 1200°C in steam and significant TiO2, and therefore Ti2AlC may be challenging to form as a cladding or a coating. Alloy development for FeCrAl is seeking to maintain its steam oxidation resistance to 1475°C, while reducing its Cr content to minimize susceptibility to irradiation-assisted α´ formation. The composition effects and critical limits to retaining protective scale formation at > 1400°C are still being evaluated.

  9. Selective Integration in the Material-Point Method

    DEFF Research Database (Denmark)

    Andersen, Lars; Andersen, Søren; Damkilde, Lars

    2009-01-01

    The paper deals with stress integration in the material-point method. In order to avoid parasitic shear in bending, a formulation is proposed, based on selective integration in the background grid that is used to solve the governing equations. The suggested integration scheme is compared...... to a traditional material-point-method computation in which the stresses are evaluated at the material points. The deformation of a cantilever beam is analysed, assuming elastic or elastoplastic material behaviour....

  10. Selection of materials in nuclear fuel: present and future

    International Nuclear Information System (INIS)

    Munoz-Reja, C.; Fuentes, L.; Garcia de la Infanta, J. M.; Munoz Sicilia, A.

    2013-01-01

    One of the main aspects of the nuclear fuel is the selection of materials for the components. The operating conditions of the fuel elements impose a major challenge to materials: high temperature, corrosive aqueous environment, high mechanical properties, long periods of time under these extreme conditions and what is the differentiating factor; the effect of irradiation. The materials are selected to fulfill these severe requirements and also to be able to control and to predict its behavior in the working conditions. Their development, in terms of composition and processing, is based on the continuous follow-up of the operation behavior. Many of these materials are specific of the nuclear industry, such as the uranium dioxide and the zirconium alloys. This article presents the selection and development of the nuclear fuel materials as a function of the services requirements. It also includes a view of the new nuclear fuels materials that are being raised after Fukushima accident. (Author)

  11. Photovoltaic module encapsulation design and materials selection, volume 1

    Science.gov (United States)

    Cuddihy, E.; Carroll, W.; Coulbert, C.; Gupta, A.; Liang, R. H.

    1982-01-01

    Encapsulation material system requirements, material selection criteria, and the status and properties of encapsulation materials and processes available are presented. Technical and economic goals established for photovoltaic modules and encapsulation systems and their status are described. Available encapsulation technology and data are presented to facilitate design and material selection for silicon flat plate photovoltaic modules, using the best materials available and processes optimized for specific power applications and geographic sites. The operational and environmental loads that encapsulation system functional requirements and candidate design concepts and materials that are identified to have the best potential to meet the cost and performance goals for the flat plate solar array project are described. Available data on encapsulant material properties, fabrication processing, and module life and durability characteristics are presented.

  12. Selection of views to materialize using simulated annealing algorithms

    Science.gov (United States)

    Zhou, Lijuan; Liu, Chi; Wang, Hongfeng; Liu, Daixin

    2002-03-01

    A data warehouse contains lots of materialized views over the data provided by the distributed heterogeneous databases for the purpose of efficiently implementing decision-support or OLAP queries. It is important to select the right view to materialize that answer a given set of queries. The goal is the minimization of the combination of the query evaluation and view maintenance costs. In this paper, we have addressed and designed algorithms for selecting a set of views to be materialized so that the sum of processing a set of queries and maintaining the materialized views is minimized. We develop an approach using simulated annealing algorithms to solve it. First, we explore simulated annealing algorithms to optimize the selection of materialized views. Then we use experiments to demonstrate our approach. The results show that our algorithm works better. We implemented our algorithms and a performance study of the algorithms shows that the proposed algorithm gives an optimal solution.

  13. ABOUT INDEX EVALUATION OF MATERIAL RESOURCE SUPPLIER SELECTION

    Directory of Open Access Journals (Sweden)

    V. A. Skochinskaya

    2008-01-01

    Full Text Available The paper analyzes existing methods for evaluation of material resource supplier selection. It shows advantages and shortcomings of the present evaluation systems. The necessity for application of an index evaluation is justified in the paper. The paper contains rating (index evaluation for material resource supplier selection which is based on the application of quantitative (index tool instead of an expert (numerical evaluation. 

  14. Wholesale debris removal from LEO

    Science.gov (United States)

    Levin, Eugene; Pearson, Jerome; Carroll, Joseph

    2012-04-01

    Recent advances in electrodynamic propulsion make it possible to seriously consider wholesale removal of large debris from LEO for the first time since the beginning of the space era. Cumulative ranking of large groups of the LEO debris population and general limitations of passive drag devices and rocket-based removal systems are analyzed. A candidate electrodynamic debris removal system is discussed that can affordably remove all debris objects over 2 kg from LEO in 7 years. That means removing more than 99% of the collision-generated debris potential in LEO. Removal is performed by a dozen 100-kg propellantless vehicles that react against the Earth's magnetic field. The debris objects are dragged down and released into short-lived orbits below ISS. As an alternative to deorbit, some of them can be collected for storage and possible in-orbit recycling. The estimated cost per kilogram of debris removed is a small fraction of typical launch costs per kilogram. These rates are low enough to open commercial opportunities and create a governing framework for wholesale removal of large debris objects from LEO.

  15. Selective Postevent Review and Children's Memory for Nonreviewed Materials

    Science.gov (United States)

    Conroy, R.; Salmon, K.

    2005-01-01

    Two experiments investigated the impact of selective postevent questioning on children's memory for nonreviewed materials. In both experiments, children participated in a series of novel activities. Children in the selective-review condition were subsequently questioned about half of these and comparisons were made to memory in a no-review…

  16. Mitochondrial genome of the African lion Panthera leo leo.

    Science.gov (United States)

    Ma, Yue-ping; Wang, Shuo

    2015-01-01

    In this study, the complete mitochondrial genome sequence of the African lion P. leo leo was reported. The total length of the mitogenome was 17,054 bp. It contained the typical mitochondrial structure, including 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes and 1 control region; 21 of the tRNA genes folded into typical cloverleaf secondary structure except for tRNASe. The overall composition of the mitogenome was A (32.0%), G (14.5%), C (26.5%) and T (27.0%). The new sequence will provide molecular genetic information for conservation genetics study of this important large carnivore.

  17. Considerations in selecting tubing materials for CANDU steam generators

    International Nuclear Information System (INIS)

    Hemmings, R.L.

    1978-01-01

    Corrosion resistance is the major consideration in selecting tubing material for CANDU steam generators. Corrosion, and additional considerations, lead to the following steam generator tubing material recommendations: for CANDU-BPHWR's (boiling pressurized heavy water reactors) low-cobalt Incoloy-800; for CANDU-PHWR's (pressurized, non-boiling, heavy water reactors), low-cobalt Monel-400

  18. Passivation Strategies on Board Airbus ds Leo Pcdus

    Directory of Open Access Journals (Sweden)

    Lapeña Emilio

    2017-01-01

    This paper deals with the different strategies followed in the Airbus DS LEO PCDUs regarding the implementation of the passivation function in several LEO missions with different architectures (DET and MPPT solar array power conditioning. In the selection of the solution implemented in the frame of every mission, a key driver is the degree of advance in the test performed over flight representative battery modules regarding their safe behavior when deeply depleted after a long period in orbit with the passivation applied over the spacecraft.

  19. Basic Thermal Parameters of Selected Foods and Food Raw Materials

    Directory of Open Access Journals (Sweden)

    Monika Božiková

    2017-01-01

    Full Text Available In general, processing and manipulation with foods and food raw materials have significant influence on their physical properties. The article is focused on thermophysical parameters measurement of selected foods and food raw materials. There were examined thermal conductivity and thermal diffusivity of selected materials. For detection of thermal parameters was used instrument Isomet 2104, which principle of measurement is based on transient methods. In text are presented summary results of thermal parameters measurement for various foods and food raw materials as: granular materials – corn flour and wheat flour; fruits, vegetables and fruit products – grated apple, dried apple and apple juice; liquid materials – milk, beer etc. Measurements were performed in two temperature ranges according to the character of examined material. From graphical relations of thermophysical parameter is evident, that thermal conductivity and diffusivity increases with temperature and moisture content linearly, only for granular materials were obtained non‑linear dependencies. Results shows, that foods and food raw materials have different thermal properties, which are influenced by their type, structure, chemical and physical properties. From presented results is evident, that basic thermal parameters are important for material quality detection in food industry.

  20. Properties of selected superconductive materials, 1978 supplement. Technical note

    International Nuclear Information System (INIS)

    Roberts, B.W.

    1978-10-01

    This report includes data on additional superconductive materials extracted from the world literature up to fall 1977 and is an addendum to the data set published in J. Phys. Chem. Ref. Data 5, no. 3, 581-821 (1976) (Reprint no. 84). The data presented are new values and have not been selected or compared to values (except for selected values of the elements) previously assembled by the Superconductive Materials Data Center. The properties included are composition, critical temperature, critical magnetic field, crystal structure and the results of negative experiments. Special tabulations of high magnetic field materials with Type II behavior and materials with organic components are included. All entries are keyed to the literature. A list of recent reviews centered on superconductive materials is included

  1. Leo Tolstoy the Spiritual Educator

    Science.gov (United States)

    Moulin, Dan

    2008-01-01

    This paper considers the often overlooked religious and educational works of the Russian novelist Leo Tolstoy (1828-1910). After outlining Tolstoy's life, religious and educational views, it is argued that Tolstoy has much to offer spiritual educators today. In particular, it suggests Tolstoy's insistence on the absolute and eternal nature of…

  2. An annotated history of container candidate material selection

    International Nuclear Information System (INIS)

    McCright, R.D.

    1988-07-01

    This paper documents events in the Nevada Nuclear Waste Storage Investigations (NNWSI) Project that have influenced the selection of metals and alloys proposed for fabrication of waste package containers for permanent disposal of high-level nuclear waste in a repository at Yucca Mountain, Nevada. The time period from 1981 to 1988 is covered in this annotated history. The history traces the candidate materials that have been considered at different stages of site characterization planning activities. At present, six candidate materials are considered and described in the 1988 Consultation Draft of the NNWSI Site Characterization Plan (SCP). The six materials are grouped into two alloy families, copper-base materials and iron to nickel-base materials with an austenitic structure. The three austenitic candidates resulted from a 1983 survey of a longer list of candidate materials; the other three candidates resulted from a special request from DOE in 1984 to evaluate copper and copper-base alloys. 24 refs., 2 tabs

  3. A fuzzy logic based PROMETHEE method for material selection problems

    Directory of Open Access Journals (Sweden)

    Muhammet Gul

    2018-03-01

    Full Text Available Material selection is a complex problem in the design and development of products for diverse engineering applications. This paper presents a fuzzy PROMETHEE (Preference Ranking Organization Method for Enrichment Evaluation method based on trapezoidal fuzzy interval numbers that can be applied to the selection of materials for an automotive instrument panel. Also, it presents uniqueness in making a significant contribution to the literature in terms of the application of fuzzy decision-making approach to material selection problems. The method is illustrated, validated, and compared against three different fuzzy MCDM methods (fuzzy VIKOR, fuzzy TOPSIS, and fuzzy ELECTRE in terms of its ranking performance. Also, the relationships between the compared methods and the proposed scenarios for fuzzy PROMETHEE are evaluated via the Spearman’s correlation coefficient. Styrene Maleic Anhydride and Polypropylene are determined optionally as suitable materials for the automotive instrument panel case. We propose a generic fuzzy MCDM methodology that can be practically implemented to material selection problem. The main advantages of the methodology are consideration of the vagueness, uncertainty, and fuzziness to decision making environment.

  4. Selection of material balance areas and item control areas

    International Nuclear Information System (INIS)

    1975-04-01

    Section 70.58, ''Fundamental Nuclear Material Controls,'' of 10 CFR Part 70, ''Special Nuclear Material,'' requires certain licensees authorized to possess more than one effective kilogram of special nuclear material to establish Material Balance Areas (MBAs) or Item Control Areas (ICAs) for the physical and administrative control of nuclear materials. This section requires that: (1) each MBA be an identifiable physical area such that the quantity of nuclear material being moved into or out of the MBA is represented by a measured value; (2) the number of MBAs be sufficient to localize nuclear material losses or thefts and identify the mechanisms; (3) the custody of all nuclear material within an MBA or ICA be the responsibility of a single designated individual; and (4) ICAs be established according to the same criteria as MBAs except that control into and out of such areas would be by item identity and count for previously determined special nuclear material quantities, the validity of which must be ensured by tamper-safing unless the items are sealed sources. This guide describes bases acceptable to the NRC staff for the selection of material balance areas and item control areas. (U.S.)

  5. New ion selective materials. Application to the selective extraction of caesium

    International Nuclear Information System (INIS)

    Favre-Reguillon, Alain

    1996-01-01

    This research thesis addresses the synthesis and assessment of ion selective materials. The first part reports the development of a general method of assessment of ion selective materials. In the second part, the author describes different methods used to insolubilize macro-cycles on hydrophilic polymers. The obtained polyurethanes are synthesised. These hydrophilic polymers display interesting complexing properties and selectivities with respect to cations of alkali metals. Then the author addresses the improvement of selectivity with respect to caesium of ion exchange resorcinol-formaldehyde resins. Different factors affecting selectivity are identified, and the concept of molecular print is used to study the improvement of selectivity. The effect of macro-cyclic structures on phenolic resins with respect to caesium is highlighted [fr

  6. Quality indexes for selecting control materials of the nuclear reactors

    International Nuclear Information System (INIS)

    Martinez-Val, J.M.; Pena, J.; Esteban Naudin, A.

    1981-01-01

    Quality indexes are established and valued for selecting control materials, The requirements for accomplishing such purposes are explained with detailed analysis: absortion cross section must be as high as possible, adequate reactivity evolution versus depletion, good resistance to radiation, appropiate thermal stability, mechanical resistance and ductility, chemical compatibility with the environment, good heat transfer properties, abundant in the nature and low costs. At present Westinghouse desire to commercialize hafnium as control material shows the exciting task of looking for new materials controlling nuclear reactors. (auth.)

  7. Corrosion behaviour of materials selected for FMIT lithium system

    Energy Technology Data Exchange (ETDEWEB)

    Bazinet, G.D.; Brehm, W.F.

    1983-09-01

    The corrosion behavior of selected materials in a liquid lithium environment was studied in support of system and component designs for the Fusion Materials Irradiation Test (FMIT) Facility. Testing conditions ranged from about 3700 to about6500 hours of exposure to flowing lithium at temperatures from 230/sup 0/ to 270/sup 0/C and static lithium at temperatures from 200/sup 0/ to 500/sup 0/C. Principal areas of investigation included lithium corrosion/erosion effects on FMIT lithium system baseline and candidate materials. Material coupons and full-size prototypic components were evaluated to determine corrosion rates, fatigue crack growth rates, structural compatibility, and component acceptability for the lithium system. Based on the results of these studies, concerns regarding system materials and component designs were satisfactorily resolved to support a 20-year design life requirement for the FMIT lithium system.

  8. Corrosion behaviour of materials selected for FMIT lithium system

    International Nuclear Information System (INIS)

    Bazinet, G.D.; Brehm, W.F.

    1983-01-01

    The corrosion behavior of selected materials in a liquid lithium environment was studied in support of system and component designs for the Fusion Materials Irradiation Test (FMIT) Facility. Testing conditions ranged from about 3700 to about6500 hours of exposure to flowing lithium at temperatures from 230 0 to 270 0 C and static lithium at temperatures from 200 0 to 500 0 C. Principal areas of investigation included lithium corrosion/erosion effects on FMIT lithium system baseline and candidate materials. Material coupons and full-size prototypic components were evaluated to determine corrosion rates, fatigue crack growth rates, structural compatibility, and component acceptability for the lithium system. Based on the results of these studies, concerns regarding system materials and component designs were satisfactorily resolved to support a 20-year design life requirement for the FMIT lithium system

  9. Selected Audio-Visual Materials for Consumer Education. [New Version.

    Science.gov (United States)

    Johnston, William L.

    Ninety-two films, filmstrips, multi-media kits, slides, and audio cassettes, produced between 1964 and 1974, are listed in this selective annotated bibliography on consumer education. The major portion of the bibliography is devoted to films and filmstrips. The main topics of the audio-visual materials include purchasing, advertising, money…

  10. Materials selection for a transport packaging of Mo-99

    International Nuclear Information System (INIS)

    Hara, Debora H.S.; Lucchesi, Raquel F.; Mancini, Victor A.; Rossi, Jesualdo L.; Fiore, Marina

    2015-01-01

    The radiopharmaceuticals are radioactive isotopes used in nuclear medicine for more accurate diagnosis and treatment of diseases or dysfunctions. Currently, the most important radionuclide for the preparation of radiopharmaceuticals for diagnostic purposes is technetium-99m ( 99m Tc), a product of the radioactive decay of molybdenum-99 (Mo-99). The aim of this work was the materials selection that can enable the manufacture of a package for Mo-99 transport with the aid of CES EduPack program and the methodology developed by Ashby. The ESTAR program was used to check the occurrence of Bremsstrahlung and the XCOM program was used to calculate the attenuation coefficient of gamma radiation from some of the selected materials for the shield; after, the thickness required for radiation shielding was calculated. From the results, the materials selected as potential candidates for the manufacture of the shielding were the tungsten alloys. Related to the thermal insulation and the impact protection, woods, plywoods and particle boards stand out. With regard to internal and external coatings, the selected materials focus on groups of steels and nickel alloys. (author)

  11. 1997 IEEE/LEOS Summer Topical Meeting on Gallium Nitride Materials, Processing and Devices Held in Montreal, Quebec, Canada on 11-15 August 1997

    Science.gov (United States)

    1998-01-01

    refractive index differences in the two branches, their respective dispersion curves will intersect at a certain wavelength, according to our design...wavelengths, DBRs are usually grown lattice- matched to InP using quaternary and ternary phosphide alloys in spite of the low refractive in- dex...validating the refractive index model. In a third step, mirrors based on arsenide-antimonide materials were designed to operate at 1.3 ^.m

  12. An integrated approach towards future ballistic neck protection materials selection.

    Science.gov (United States)

    Breeze, John; Helliker, Mark; Carr, Debra J

    2013-05-01

    Ballistic protection for the neck has historically taken the form of collars attached to the ballistic vest (removable or fixed), but other approaches, including the development of prototypes incorporating ballistic material into the collar of an under body armour shirt, are now being investigated. Current neck collars incorporate the same ballistic protective fabrics as the soft armour of the remaining vest, reflecting how ballistic protective performance alone has historically been perceived as the most important property for neck protection. However, the neck has fundamental differences from the thorax in terms of anatomical vulnerability, flexibility and equipment integration, necessitating a separate solution from the thorax in terms of optimal materials selection. An integrated approach towards the selection of the most appropriate combination of materials to be used for each of the two potential designs of future neck protection has been developed. This approach requires evaluation of the properties of each potential material in addition to ballistic performance alone, including flexibility, mass, wear resistance and thermal burden. The aim of this article is to provide readers with an overview of this integrated approach towards ballistic materials selection and an update of its current progress in the development of future ballistic neck protection.

  13. Supercritical boiler material selection using fuzzy analytic network process

    Directory of Open Access Journals (Sweden)

    Saikat Ranjan Maity

    2012-08-01

    Full Text Available The recent development of world is being adversely affected by the scarcity of power and energy. To survive in the next generation, it is thus necessary to explore the non-conventional energy sources and efficiently consume the available sources. For efficient exploitation of the existing energy sources, a great scope lies in the use of Rankin cycle-based thermal power plants. Today, the gross efficiency of Rankin cycle-based thermal power plants is less than 28% which has been increased up to 40% with reheating and regenerative cycles. But, it can be further improved up to 47% by using supercritical power plant technology. Supercritical power plants use supercritical boilers which are able to withstand a very high temperature (650-720˚C and pressure (22.1 MPa while producing superheated steam. The thermal efficiency of a supercritical boiler greatly depends on the material of its different components. The supercritical boiler material should possess high creep rupture strength, high thermal conductivity, low thermal expansion, high specific heat and very high temperature withstandability. This paper considers a list of seven supercritical boiler materials whose performance is evaluated based on seven pivotal criteria. Given the intricacy and difficulty of this supercritical boiler material selection problem having interactions and interdependencies between different criteria, this paper applies fuzzy analytic network process to select the most appropriate material for a supercritical boiler. Rene 41 is the best supercritical boiler material, whereas, Haynes 230 is the worst preferred choice.

  14. Materials selection guidelines for geothermal energy utilization systems

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, P.F. II; Conover, M.F.

    1981-01-01

    This manual includes geothermal fluid chemistry, corrosion test data, and materials operating experience. Systems using geothermal energy in El Salvador, Iceland, Italy, Japan, Mexico, New Zealand, and the United States are described. The manual provides materials selection guidelines for surface equipment of future geothermal energy systems. The key chemical species that are significant in determining corrosiveness of geothermal fluids are identified. The utilization modes of geothermal energy are defined as well as the various physical fluid parameters that affect corrosiveness. Both detailed and summarized results of materials performance tests and applicable operating experiences from forty sites throughout the world are presented. The application of various non-metal materials in geothermal environments are discussed. Included in appendices are: corrosion behavior of specific alloy classes in geothermal fluids, corrosion in seawater desalination plants, worldwide geothermal power production, DOE-sponsored utilization projects, plant availability, relative costs of alloys, and composition of alloys. (MHR)

  15. Material selection for Multi-Function Waste Tank Facility tanks

    International Nuclear Information System (INIS)

    Carlos, W.C.

    1994-01-01

    This report briefly summarizes the history of the materials selection for the US Department of Energy's high-level waste carbon steel storage tanks. It also provide an evaluation of the materials for the construction of new tanks at the Multi-Function Waste Tank Facility. The evaluation included a materials matrix that summarized the critical design, fabrication, construction, and corrosion resistance requirements; assessed each requirement; and cataloged the advantages and disadvantages of each material. This evaluation is based on the mission of the Multi-Function Waste Tank Facility. On the basis of the compositions of the wastes stored in Hanford waste tanks, it is recommended that tanks for the Multi-Function Waste Tank Facility be constructed of normalized ASME SA 516, Grade 70, carbon steel

  16. Review of selective laser melting: Materials and applications

    Energy Technology Data Exchange (ETDEWEB)

    Yap, C. Y., E-mail: cyap001@e.ntu.edu.sg [Singapore Centre for 3D Printing, School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Block N3.1 - B2c - 01, Singapore 639798 (Singapore); Energy Research Institute @ NTU, Interdisciplinary Graduate School, Nanyang Technological University, 50 Nanyang Avenue, Block S2 - B3a - 01, Singapore 639798 (Singapore); Chua, C. K., E-mail: mckchua@ntu.edu.sg; Liu, Z. H., E-mail: azhliu@ntu.edu.sg; Zhang, D. Q., E-mail: zhangdq@ntu.edu.sg; Loh, L. E., E-mail: leloh1@e.ntu.edu.sg; Sing, S. L., E-mail: sing0011@e.ntu.edu.sg [Singapore Centre for 3D Printing, School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Block N3.1 - B2c - 01, Singapore 639798 (Singapore); Dong, Z. L., E-mail: zldong@ntu.edu.sg [School of Materials Science & Engineering, Nanyang Technological University, 50 Nanyang Avenue, Block N4.1, Singapore 639798 (Singapore)

    2015-12-15

    Selective Laser Melting (SLM) is a particular rapid prototyping, 3D printing, or Additive Manufacturing (AM) technique designed to use high power-density laser to melt and fuse metallic powders. A component is built by selectively melting and fusing powders within and between layers. The SLM technique is also commonly known as direct selective laser sintering, LaserCusing, and direct metal laser sintering, and this technique has been proven to produce near net-shape parts up to 99.9% relative density. This enables the process to build near full density functional parts and has viable economic benefits. Recent developments of fibre optics and high-power laser have also enabled SLM to process different metallic materials, such as copper, aluminium, and tungsten. Similarly, this has also opened up research opportunities in SLM of ceramic and composite materials. The review presents the SLM process and some of the common physical phenomena associated with this AM technology. It then focuses on the following areas: (a) applications of SLM materials and (b) mechanical properties of SLM parts achieved in research publications. The review is not meant to put a ceiling on the capabilities of the SLM process but to enable readers to have an overview on the material properties achieved by the SLM process so far. Trends in research of SLM are also elaborated in the last section.

  17. Review of selective laser melting: Materials and applications

    Science.gov (United States)

    Yap, C. Y.; Chua, C. K.; Dong, Z. L.; Liu, Z. H.; Zhang, D. Q.; Loh, L. E.; Sing, S. L.

    2015-12-01

    Selective Laser Melting (SLM) is a particular rapid prototyping, 3D printing, or Additive Manufacturing (AM) technique designed to use high power-density laser to melt and fuse metallic powders. A component is built by selectively melting and fusing powders within and between layers. The SLM technique is also commonly known as direct selective laser sintering, LaserCusing, and direct metal laser sintering, and this technique has been proven to produce near net-shape parts up to 99.9% relative density. This enables the process to build near full density functional parts and has viable economic benefits. Recent developments of fibre optics and high-power laser have also enabled SLM to process different metallic materials, such as copper, aluminium, and tungsten. Similarly, this has also opened up research opportunities in SLM of ceramic and composite materials. The review presents the SLM process and some of the common physical phenomena associated with this AM technology. It then focuses on the following areas: (a) applications of SLM materials and (b) mechanical properties of SLM parts achieved in research publications. The review is not meant to put a ceiling on the capabilities of the SLM process but to enable readers to have an overview on the material properties achieved by the SLM process so far. Trends in research of SLM are also elaborated in the last section.

  18. Review of selective laser melting: Materials and applications

    International Nuclear Information System (INIS)

    Yap, C. Y.; Chua, C. K.; Liu, Z. H.; Zhang, D. Q.; Loh, L. E.; Sing, S. L.; Dong, Z. L.

    2015-01-01

    Selective Laser Melting (SLM) is a particular rapid prototyping, 3D printing, or Additive Manufacturing (AM) technique designed to use high power-density laser to melt and fuse metallic powders. A component is built by selectively melting and fusing powders within and between layers. The SLM technique is also commonly known as direct selective laser sintering, LaserCusing, and direct metal laser sintering, and this technique has been proven to produce near net-shape parts up to 99.9% relative density. This enables the process to build near full density functional parts and has viable economic benefits. Recent developments of fibre optics and high-power laser have also enabled SLM to process different metallic materials, such as copper, aluminium, and tungsten. Similarly, this has also opened up research opportunities in SLM of ceramic and composite materials. The review presents the SLM process and some of the common physical phenomena associated with this AM technology. It then focuses on the following areas: (a) applications of SLM materials and (b) mechanical properties of SLM parts achieved in research publications. The review is not meant to put a ceiling on the capabilities of the SLM process but to enable readers to have an overview on the material properties achieved by the SLM process so far. Trends in research of SLM are also elaborated in the last section

  19. Durability of Selected Membrane Materials when Exposed to Chlorine Gas

    Energy Technology Data Exchange (ETDEWEB)

    Eikeland, Marianne Soerflaten

    2001-03-01

    This thesis is focusing on the durability of selected membrane materials when exposed to chlorine gas in the temperature range 30-100{sup o}C. Studies of the changes of membrane separation properties and the mechanisms promoting these changes have been studied. The selected membrane materials were poly(dimethylsioxane) (PDMS), Fluorel, fluorosilicone, and blends of PDMS and Fluorel. The thesis is organised in seven chapters. The first chapter gives an introduction to the background of the work. The second chapter presents the theory for gas separation using dense rubbery membranes. The properties of the selected membrane materials are presented in chapter three. The fourth chapter describes degradation mechanisms for polymeric materials in general and for the selected membrane materials in particular. Presentation of the experimental work is given in chapter five, while the results with discussions are presented in chapter six. The conclusions and recommendations for further studies are given in chapter seven. Five appendixes are attached: Appendix A describes the calculations of permeability and solubility coefficients and the accuracy of the experimental measurements. Appendix B summarises the measured values in tables and Appendix C describes the analytical methods. Appendix D gives the properties of the gases used in the experiments. Appendix E is the article ''Durability of Poly(dimethylsiloxane) when Exposed to Chlorine Gas'', submitted to the Journal of Applied Polymer Science. Highly crosslinked PDMS was found to have an initial high permeability for chlorine gas and a high Cl{sub 2}/O{sub 2} selectivity. However when exposed to chlorine gas the permeability decreased significantly. Crosslinking of the PDMS polymer chain and chlorination of the polymer gave a denser polymer structure and thus lower permeability. Fluorel showed very low permeabilities and selectivities for the gases in question and was thus not interesting for this

  20. Merit exponents and control area diagrams in materials selection

    International Nuclear Information System (INIS)

    Zander, Johan; Sandstroem, Rolf

    2011-01-01

    Highlights: → Merit exponents are introduced to generalise the merit indices commonly used in materials selection. → The merit exponents can rank materials in general design situations. → To allow identification of the active merit exponent(s), control area diagrams are used. → Principles for generating the control area diagrams are presented. -- Abstract: Merit indices play a fundamental role in materials selection, since they enable ranking of materials. However, the conventional formulation of merit indices is associated with severe limitations. They are dependent on the explicit solution of the variables in the equations for the constraints from the design criteria. Furthermore, it is not always easy to determine which the controlling merit index is. To enable the ranking of materials in more general design cases, merit exponents are introduced as generalisations of the merit indices. Procedures are presented for how to compute the merit exponents numerically without having to solve equations algebraically. Merit exponents (and indices) are only valid in a certain range of property values. To simplify the identification of the controlling merit exponent, it is suggested that so called control area diagrams are used. These diagrams consist of a number of domains, each showing the active constraints and the controlling merit exponent. It is shown that the merit exponents play a crucial role when the control area diagram (CAD) is set up. The principles in the paper are developed for mechanically loaded components and are illustrated for engineering beams with two or three geometric variables.

  1. Development of Knitted Materials Selection for Compression Underwear

    Directory of Open Access Journals (Sweden)

    Cheng Zhe

    2017-06-01

    Full Text Available The presented research deals with the development of comfortable male underwear taking into account the development of pattern block methods and the analysis of the relationships existing between the compression pressure, the knitted materials properties, and some push-up effects. The main aim of this study is to achieve the technical selection of the materials based on KES-FB evaluations.The ease value has been used as the main index to connect the structural design of underwear, on one hand, and the body sizes, on other hand. A “bodyshell” system for testing the soft tissue of male bodies by FlexiForce sensor has been implemented. The pressures under the shells at six different places on the male body with ease changing have been tested.The collected results including maximum-possible pressure and material tensile indexes measured thanks to KES-FB have been analyzed in order to find the most relevant indexes of the material properties. A mathematical equations based on relationships combining theoretical model with practical application have been established. These equations will be helpful for the consumers and designers to select “the suitable knitting materials for male underwear” and they can be used too in the perspective of parameterization in CAD, in order to improve product developments efficiency.

  2. Significance of ITER IWS Material Selection and Qualification

    Science.gov (United States)

    Mehta, Bhoomi K.; Raval, Jigar; Maheshwari, Abha; Laad, Rahul; Singh, Gurlovleen; Pathak, Haresh

    2017-04-01

    In-Wall Shielding (IWS) is one of the important components of ITER Vacuum Vessel (VV) which fills the space between double walls of VV with cooling water. Procurement Arrangement (PA) for IWS has been signed with Indian Domestic Agency (INDA). Procurement of IWS materials, fabrication of IWS blocks and its delivery to respective Domestic Agency (DA) and ITER Organization (IO) are the main scope of this PA. Hence, INDIA is the only country which is contributing to VV IWS among all seven ITER partners. The main functions of the IWS are to provide Neutron Shielding with blanket, VV shells and water during plasma operations and to reduce ripple of the Toroidal Magnetic Field. To meet these functional requirements IWS blocks are made up of special materials (Borated Steels SS304 B4 & SS304 B7, Ferritic Steels SS 430, Austenitic Steel SS 316 L (N)-IG, XM-19 and Inconel-625) which are qualified, reliable and traceable for the design assessment. The choice of these materials has a significant influence on performance, maintainability, licensing, detailed design parameters and waste disposal. The main reasons for the materials selected for IWS are its high mechanical strength at operating temperatures, water chemistry properties, excellent fabrication characteristics and low cost relative to other similar materials. All the materials are qualified with respect to their respective codes (ASTM/EN standards with additional requirements as described in RCC-MR code 2007) and ITER requirements. Agreed Notified Body (ANB) has control conformity of materials certificates with approved material specification and traceability procedure for Safety Important Component (SIC). The procurement strategy for all the IWS materials has been developed in close collaboration with IO, ANB and Industries as per Product Procurement Specification (PPS). The R&D for sample, bulk material production, testing, inspection and handling as required are carried out by IN DA and IO. At present almost all

  3. Route selection for the transport of hazardous materials

    Energy Technology Data Exchange (ETDEWEB)

    Seiler, F A

    1988-12-01

    The factors governing the risk-weighted selection of routes for transport of hazardous materials are analyzed. Starting from a formulation for the total risk of these transports that assumes complete information, approximations for the more realistic case of partial and uncertain information are discussed. These approximations involve well-known risk assessment techniques and mathematical methods; among the latter, Monte Carlo calculations hold the most promise. The actual route selection is based on an index of total societal cost, evaluated for a set of potential routes. (author)

  4. Selection of materials with potential in sensible thermal energy storage

    International Nuclear Information System (INIS)

    Fernandez, A.I.; Martinez, M.; Segarra, M.; Martorell, I.; Cabeza, L.F.

    2010-01-01

    Thermal energy storage is a technology under investigation since the early 1970s. Since then, numerous new applications have been found and much work has been done to bring this technology to the market. Nevertheless, the materials used either for latent or for sensible storage were mostly investigated 30 years ago, and the research has lead to improvement in their performance under different conditions of applications. In those years a significant number of new materials were developed in many fields other than storage and energy, but a great effort to characterize and classify these materials was done. Taking into account the fact that thousands of materials are known and a large number of new materials are developed every year, the authors use the methodology for materials selection developed by Prof. Ashby to give an overview of other materials suitable to be used in thermal energy storage. Sensible heat storage at temperatures between 150 and 200 C is defined as a case study and two different scenarios were considered: long term sensible heat storage and short term sensible heat storage. (author)

  5. Selecting a radiation tolerant piezoelectric material for nuclear reactor applications

    Energy Technology Data Exchange (ETDEWEB)

    Parks, D. A.; Reinhardt, B. T.; Tittmann, B. R. [Department of Engineering Science and Mechanics, Penn State, University Park, PA 16803 (United States)

    2013-01-25

    Bringing systems for online monitoring of nuclear reactors to fruition has been delayed by the lack of suitable ultrasonic sensors. Recent work has demonstrated the capability of an AlN sensor to perform ultrasonic evaluation in an actual nuclear reactor. Although the AlN demonstrated sustainability, no loss in signal amplitude and d{sub 33} up to a fast and thermal neutron fluence of 1.85 Multiplication-Sign 1018 n/cm{sup 2} and 5.8 Multiplication-Sign 1018 n/cm{sup 2} respectively, no formal process to selecting a suitable sensor material was made. It would be ideal to use first principles approaches to somehow reduce each candidate piezoelectric material to a simple ranking showing directly which materials one should expect to be most radiation tolerant. However, the complexity of the problem makes such a ranking impractical and one must appeal to experimental observations. This should not be of any surprise to one whom is familiar with material science as most material properties are obtained in this manner. Therefore, this work adopts a similar approach, the mechanisms affecting radiation tolerance are discussed and a good engineering sense is used for material qualification of the candidate piezoelectric materials.

  6. ERG review of waste package container materials selection and corrosion

    International Nuclear Information System (INIS)

    Moak, D.P.; Perrin, J.S.

    1986-07-01

    The Engineering Review Group (ERG) was established by the Office of Nuclear Waste Isolation (ONWI) to help evaluate engineering-related issues in the US Department of Energy's nuclear waste repository program. The October 1984 meeting of the ERG reviewed the waste package container materials selection and corrosion. This report documents the ERG's comments and recommendations on these subjects and the ONWI response to the specific points raised by the ERG

  7. Selection and evaluation of materials for thermoelectric applications II

    Energy Technology Data Exchange (ETDEWEB)

    Sharp, J W

    1997-07-01

    In good thermoelectrics phonons have short mean free paths, and charge carriers have long ones. The other requirements are a multivalley band structure and a band gap greater than 0.1 eV for the 200 to 300 K temperature range. The author discusses the use of solid state physics and chemistry concepts, along with atomic and crystal structure data, to select the new materials most likely to meet these criteria.

  8. Material Selection for Microchannel Heatsink: Conjugate Heat Transfer Simulation

    Science.gov (United States)

    Uday Kumar, A.; Javed, Arshad; Dubey, Satish K.

    2018-04-01

    Heat dissipation during the operation of electronic devices causes rise in temperature, which demands an effective thermal management for their performance, life and reliability. Single phase liquid cooling in microchannels is an effective and proven technology for electronics cooling. However, due to the ongoing trends of miniaturization and developments in the microelectronics technology, the future needs of heat flux dissipation rate are expected to rise to 1 kW/cm2. Air cooled systems are unable to meet this demand. Hence, liquid cooled heatsinks are preferred. This paper presents conjugate heat transfer simulation of single phase flow in microchannels with application to electronic cooling. The numerical model is simulated for different materials: copper, aluminium and silicon as solid and water as liquid coolant. The performances of microchannel heatsink are analysed for mass flow rate range of 20-40 ml/min. The investigation has been carried out on same size of electronic chip and heat flux in order to have comparative study of different materials. This paper is divided into two sections: fabrication techniques and numerical simulation for different materials. In the first part, a brief discussion of fabrication techniques of microchannel heatsink have been presented. The second section presents conjugate heat transfer simulation and parametric investigation for different material microchannel heatsink. The presented study and findings are useful for selection of materials for microchannel heatsink.

  9. Stochastic isotropic hyperelastic materials: constitutive calibration and model selection

    Science.gov (United States)

    Mihai, L. Angela; Woolley, Thomas E.; Goriely, Alain

    2018-03-01

    Biological and synthetic materials often exhibit intrinsic variability in their elastic responses under large strains, owing to microstructural inhomogeneity or when elastic data are extracted from viscoelastic mechanical tests. For these materials, although hyperelastic models calibrated to mean data are useful, stochastic representations accounting also for data dispersion carry extra information about the variability of material properties found in practical applications. We combine finite elasticity and information theories to construct homogeneous isotropic hyperelastic models with random field parameters calibrated to discrete mean values and standard deviations of either the stress-strain function or the nonlinear shear modulus, which is a function of the deformation, estimated from experimental tests. These quantities can take on different values, corresponding to possible outcomes of the experiments. As multiple models can be derived that adequately represent the observed phenomena, we apply Occam's razor by providing an explicit criterion for model selection based on Bayesian statistics. We then employ this criterion to select a model among competing models calibrated to experimental data for rubber and brain tissue under single or multiaxial loads.

  10. Seletividade e eficácia de controle de plantas daninhas pela associação entre óleo fúsel e herbicidas em cana-de-açúcar Selectivity and weed control efficacy of fusel oil and herbicide association in sugarcane

    Directory of Open Access Journals (Sweden)

    I.V. Pizzo

    2010-06-01

    . Entretanto, diuron+hexazinone e amicarbazone em dose completa associados com óleo fúsel não foram seletivos à concentração de sólidos solúveis no caldo e na produção de colmos, respectivamente.This work aimed to study the selectivity of fusel oil and herbicide association in the sugarcane cultivar IAC93-3046, and the efficacy of controlling the species Panicum maximum, Amaranthus deflexus, Ipomoea quamoclit, Brachiaria decumbens and Euphorbia heterophylla. The experiment was set up at the Instituto Agronômico/Centro de Cana in Ribeirão Preto, Brazil, in a randomized block design with 10 treatments and 4 replicates. The plots were composed of six 4 m sugarcane lines, 1.50 m (36 m² spaced, with half being sown with weeds for control evaluation, and the other half without weeds for selectivity evaluation. The treatments were diuron+hexazinone (1,170+330 g ha ¹; diuron+hexazinone (1,170+330 g ha-1 + fusel oil (25.0 L ha-1; diuron+hexazinone (819+231 g ha-1 + fusel oil (25.0 L ha-1; metribuzin (1,920 g ha-1; metribuzin (1,920 g ha-1 + fusel oil (25.0 L ha-1; metribuzin (1,344 g ha-1 + fusel oil (25.0 L ha-1; amicarbazone (1,400 g ha-1; amicarbazone (1,400 g ha-1 + fusel oil (25.0 L ha-1 and amicarbazone (980 g ha-1 + fusel oil (25.0 L ha-1 and no herbicides. The application was performed with pressurized sprayer and 250 L ha-1 volume under post-emergence of the culture (30 cm and weeds (10-2 cm. The herbicides diuron+hexazinone, metribuzin and amicarbazone were effective in controlling all the species alone, but only I. quamoclit and E. heterophylla did not present a satisfactory control at full dose and 70% of the dose combined with fusel oil. The same treatments were also selective for sugarcane cultivar IACSP 93-3046, when the variables height, stand, diameter and stalk yield, as well as the qualitative attributes were compared to the control. However, diuron + hexazinone and amicarbazone at a full dose associated with fusel oil were not selective for Brix% juice

  11. SELECTION OF MICROORGANISMS FOR FERMENTATION OF MEAT MATERIALS

    Directory of Open Access Journals (Sweden)

    Danylenko S. G.

    2014-08-01

    Full Text Available Principal criteria for the selection of microorganisms with a wide range of biological and technological properties for fermentation of raw meats are considered. Attention is paid to the main groups of microorganisms such as Micrococсus, Staphylococcus, Lactobacillus, Bifidobacterium and Propionibacterium which are promising for creation of bacterial preparations. To create bacterial preparations, the basic criteria of selection for microorganisms were determined as follows: the ability of microorganisms to be developed within the specific ecological niche (raw meat materials and their influence on flavor characteristics of the final product under the conditions of intensification of production technologies of meat products. Methods used for search and retrieval of technologically promising strains from different natural sources (fresh meats, minced meats, meat, dairy and sour-milk products, vegetables, fruit, brines and mixtures for salting are considered.

  12. Material Selection and Characterization for High Gradient RF Applications

    CERN Document Server

    Arnau-Izquierdo, G; Heikkinen, S; Ramsvik, T; Sgobba, Stefano; Taborelli, M; Wuensch, W

    2007-01-01

    The selection of candidate materials for the accelerating cavities of the Compact Linear Collider (CLIC) is carried out in parallel with high power RF testing. The maximum DC breakdown field of copper, copper alloys, refractory metals, aluminium and titanium have been measured with a dedicated setup. Higher maximum fields are obtained for refractory metals and for titanium, which exhibits, however, important damages after conditioning. Fatigue behaviour of copper alloys has been studied for surface and bulk by pulsed laser irradiation and ultrasonic excitation, respectively. The selected copper alloys show consistently higher fatigue resistance than copper in both experiments. In order to obtain the best local properties in the device a possible solution is a bi-metallic assembly. Junctions of molybdenum and copper-zirconium UNS C15000 alloy, achieved by HIP (Hot Isostatic Pressing) diffusion bonding or explosion bonding were evaluated for their mechanical strength. The reliability of the results obtained wit...

  13. Selective Recovery of Critical Materials from Geothermal Fluid

    Energy Technology Data Exchange (ETDEWEB)

    Mayes, Richard T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Halstenberg, Phillip W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Moyer, Bruce A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Karamalidis, Athanasios [Anactisis, LLC, Pittsburgh, PA (United States); Noack, Clint [Anactisis, LLC, Pittsburgh, PA (United States)

    2018-03-08

    This project, funded by the DOE Small Business Voucher program, assisted the partner with the development of ion-imprinted adsorbents for the selective extraction of rare earth elements (REE) from geothermal brines. This effort seeks to utilize a currently untapped resource thus diversifying the U. S. REE market. The initial stage of the program focused on the adsorbent developed by partner and optimization of the adsorbent. The adsorbent was based upon an ion imprinted ligand that was copolymerized with a crosslinker to generate the REE selectivity. During this task, the adsorbents were irradiated via electron beam at the NEO Beam Electron Beam Crosslinking Facility (Mercury Plastics, Middlefield, OH) to induce further crosslinking. The irradiation crosslinked adsorbents exhibited no difference in the Fourier transform infrared spectroscopic (FTIR) analysis suggesting inefficiency in the crosslinking. In the later stage of the effort, a new method was proposed and studied at ORNL involving a new partnership between the partner and a commercial polymer vender. This resulted in a new material being developed which allows the partner to utilize a commercial support and integrate the synthesis into a production-ready product stream. This will enhance the route to commercialization for the partner resulting in a quicker market penetration for the product. The new adsorbent exhibits selectivity for REE over transition metals commonly found within geothermal brines. Further optimization is required for enhanced selectivity, capacity, and intra-lanthanide separations.

  14. Materials Compatibility Testing in RSRM ODC: Free Cleaner Selection

    Science.gov (United States)

    Keen, Jill M.; Sagers, Neil W.; McCool, Alex (Technical Monitor)

    2001-01-01

    Government regulations have mandated production phase-outs of a number of solvents, including 1,1,1-trichloroethane, an ozone-depleting chemical (ODC). This solvent was used extensively in the production of the Reusable Solid Rocket Motors (RSRMs) for the Space Shuttle. Many tests have been performed to identify replacement cleaners. One major area of concern in the selection of a new cleaner has been compatibility. Some specific areas considered included cleaner compatibility with non-metallic surfaces, painted surfaces, support materials such as gloves and wipers as well as corrosive properties of the cleaners on the alloys used on these motors. The intent of this paper is to summarize the test logic, methodology, and results acquired from testing the many cleaner and material combinations.

  15. PLASTICITY OF SELECTED METALLIC MATERIALS IN DYNAMIC DEFORMATION CONDITIONS

    Directory of Open Access Journals (Sweden)

    Jacek PAWLICKI

    2014-06-01

    Full Text Available Characteristics of a modernized flywheel machine has been presented in the paper. The laboratory stand enables to perform dynamic tensile tests and impact bending with a linear velocity of the enforcing element in the range of 5÷40 m/s. A new data acquisition system, based on the tensometric sensors, allows for significant qualitative improvement of registered signals. Some preliminary dynamic forming tests were performed for the selected group of metallic materials. Subsequent microstructural examinations and identification of the fracture type enabled to describe a correlation between strain rate, strain and microstructure.

  16. VOCs and odors: key factors in selecting `green` building materials?

    Energy Technology Data Exchange (ETDEWEB)

    Coombs, C. [Steven Winter Associates Inc., Norwalk, CT and Washington DC (United States)

    1998-12-01

    The current state of knowledge available for selecting building materials on the basis of emissions of volatile organic compounds (VOCs) and odors is reviewed. The significance of VOCs and odors in building materials is related to their role in influencing indoor air quality. As far as toxicity is concerned, many of the VOCs detected in indoor air are relatively inert when considered singly. They are not however, unimportant because in actual fact they are invariably found in mixtures some of which can be toxic. Although knowledge of VOCs is incomplete, it is important to specify ozone-resistant polymeric building products, i.e. those that are chemically stable and inert to oxidation. In addition to VOCs, attention should also be focused on semi-volatile organic compounds (SVOCs) since they are even more persistent than VOCs and tend to offgas for prolonged periods of time. Similarly, it is reasonable to specify low-odor materials. Inclusion of issues related to complex indoor chemistry, less volatile emissions, in addition to VOCs and odor, should in time result in expanded choices of building materials that promote indoor air quality. 16 refs.,2 tabs.

  17. Selected topics in special nuclear materials safeguard system design

    International Nuclear Information System (INIS)

    King, L.L.; Thatcher, C.D.; Clarke, J.D.; Rodriguez, M.P.

    1991-01-01

    During the past two decades the improvements in circuit integration have given rise to many new applications in digital processing technology by continuously reducing the unit cost of processing power. Along with this increase in processing power a corresponding decrease in circuit volume has been achieved. Progress has been so swift that new classes of applications become feasible every 2 or 3 years. This is especially true in the application of proven new technology to special nuclear materials (SNM) safeguard systems. Several areas of application were investigated in establishing the performance requirements for the SNM safeguard system. These included the improvements in material control and accountability and surveillance by using multiple sensors to continuously monitor SNM inventory within the selected value(s); establishing a system architecture to provide capabilities needed for present and future performance requirements; and limiting operating manpower exposure to radiation. This paper describes two selected topics in the application of state-of-the-art, well-proven technology to SNM safeguard system design

  18. Design and selection of materials for sodium cooled fast reactors

    International Nuclear Information System (INIS)

    Chetal, S.C.

    2011-01-01

    Sodium cooled fast reactors are currently in operation, under construction or under design by a number of countries. The design of sodium cooled fast reactor is covered by French RCC - MR code and ASME code NH. The codes cover rules as regards to materials, design and construction. These codes do not cover the effect of irradiation and environment. Elevated temperature design criteria in nuclear codes are much stringent in comparison to non nuclear codes. Sodium corrosion is not an issue in selection of materials provided oxygen impurity in sodium is controlled for which excellent reactor operating experience is available. Austenitic stainless steels have remained the choice for the permanent structures of primary sodium system. Stabilized austenitic stainless steel are rejected because of poor operating experience and non inclusion in the design codes. Route for improved creep behaviour lies in compositional modifications in 316 class steel. However, the weldability needs to be ensured. For cold leg component is non creep regime, SS 304 class steel is favoured from overall economics. Enhanced fuel burn up can be realized by the use of 9-12%Cr 1%Mo class steel for the wrapper of MOX fuel design, and cladding and wrapper for metal fuel reactors. Minor compositional modifications of 20% cold worked 15Cr-15Ni class austenitic stainless steel will be a strong candidate for the cladding of MOX fuel design in the short term. Long term objective for the cladding will be to develop oxide dispersion strengthened steel. 9%Cr 1%Mo class steel (Gr 91) is an ideal choice for integrated once through sodium heated steam generators. One needs to incorporate operating experience from reactors and thermal power stations, industrial capability and R and D feedback in preparing the technical specifications for procurement of wrought products and welding consumables to ensure reliable operation of the components and systems over the design life. The paper highlights the design approach

  19. Development of the material selection practice - a study exploring articulation of material requirements

    DEFF Research Database (Denmark)

    Lenau, Torben Anker; Hasling, Karen Marie

    2014-01-01

    indicates that students focus on technical requirements when using the matrix and justifying their selection of materials. This is surprising since the students attend an arts and crafts oriented design school and are encouraged and guided to consider non-technical requirements, as part of the course where...... the matrix is introduced. A possible reason for the undesired behavior could be that students are allowed very freely to define their own matrices, having only little guidance to which requirements to use. A more formal procedure for making the material matrices is therefore proposed. The procedure requires...

  20. Strategies for selecting effective patient nutrition education materials.

    Science.gov (United States)

    Clayton, Laura H

    2010-10-01

    Nutrition and diet therapy are at the center of health promotion activities and self-management of chronic diseases. To assist an individual in making informed decisions regarding his or her diet and increase adherence to dietary recommendations or treatments, healthcare professionals must select health information that is appropriate to the client's level of understanding. A systematic approach in the evaluation of patient education material, whether in print or on the World Wide Web, must focus on the information's content, literacy level, graphical displays, layout and typography, motivating principles, cultural relevance, and feasibility. Additional criteria should be evaluated when accessing Web sites and include source, site credibility, conflict of interest, disclaimer, disclosure, navigation, and interactivity information.

  1. Materials selection for oxide-based resistive random access memories

    International Nuclear Information System (INIS)

    Guo, Yuzheng; Robertson, John

    2014-01-01

    The energies of atomic processes in resistive random access memories (RRAMs) are calculated for four typical oxides, HfO 2 , TiO 2 , Ta 2 O 5 , and Al 2 O 3 , to define a materials selection process. O vacancies have the lowest defect formation energy in the O-poor limit and dominate the processes. A band diagram defines the operating Fermi energy and O chemical potential range. It is shown how the scavenger metal can be used to vary the O vacancy formation energy, via controlling the O chemical potential, and the mean Fermi energy. The high endurance of Ta 2 O 5 RRAM is related to its more stable amorphous phase and the adaptive lattice rearrangements of its O vacancy

  2. Material selection and corrosion control practices in petroleum production

    International Nuclear Information System (INIS)

    Tuttle, R.N.

    1980-01-01

    The intent of this paper is to review briefly the current state of the art and to discuss some of the anticipated future oil and gas drilling and production activities which may challenge the materials selection and corrosion technologies. The current state of art discussions in this paper have been augmented by providing a list of references so that interested engineers may delve into each subject in more detail as desired. The technological areas which appear to require additional input to meet future needs include high strength tubular goods for sour gas service, corrosion resistant high strength alloys, definition of the effects of pressure, temperature, and fluid composition on corrosion behavior, and fatigue properties of various steels in seawater

  3. Materials selection for oxide-based resistive random access memories

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Yuzheng; Robertson, John [Engineering Department, Cambridge University, Cambridge CB2 1PZ (United Kingdom)

    2014-12-01

    The energies of atomic processes in resistive random access memories (RRAMs) are calculated for four typical oxides, HfO{sub 2}, TiO{sub 2}, Ta{sub 2}O{sub 5}, and Al{sub 2}O{sub 3}, to define a materials selection process. O vacancies have the lowest defect formation energy in the O-poor limit and dominate the processes. A band diagram defines the operating Fermi energy and O chemical potential range. It is shown how the scavenger metal can be used to vary the O vacancy formation energy, via controlling the O chemical potential, and the mean Fermi energy. The high endurance of Ta{sub 2}O{sub 5} RRAM is related to its more stable amorphous phase and the adaptive lattice rearrangements of its O vacancy.

  4. Leo Tolstoy's theory of sleep.

    Science.gov (United States)

    Vein, Alla A

    2008-03-01

    Throughout his life, Leo Tolstoy was fascinated by the phenomena of sleep and dreams. He composed a series of observations and judgements that were brought together under "my theory of sleep". Tolstoy was constantly preoccupied with the basic principles of "the theory". It is hard to name a work by him where a description of sleep and/or a dream does not play a vital role in the unfolding of the plot. They testify to Tolstoy's interest in the mechanism of sleep and in the processes of falling asleep and waking up. Tolstoy viewed sleep as a specific state of consciousness, and he subsequently linked the concept of sleep with the concept of death. For him sleep and awakening were experiences emblematic of life and death.

  5. ICP MS selection of radiopure materials for the GERDA experiment

    Science.gov (United States)

    di Vacri, M. L.; Nisi, S.; Cattadori, C.; Janicsko, J.; Lubashevskiy, A.; Smolnikov, A.; Walter, M.

    2015-08-01

    The GERDA (GERmanium Detector Array) experiment, located in the Gran Sasso Underground Laboratory (LNGS, Italy) aims to search for neutrinoless double beta (0νββ) decay of the 76Ge isotope. Both an ultra-low radioactivity background environment and active techniques to abate the residual background are required to reach the background index (of 10-3 counts/keV kg y) at the Qββ. In order to veto and suppress those events that partially deposit energy in Ge detectors, the readout of liquid argon (LAr) scintillation light (SL) has been implemented for the second GERDA experimental Phase. A double veto system has been designed and constructed using highly radiopure materials (scintillating fibers, wavelength shifters, polymeric foils, reflective foils). This work describes the study of lead, thorium and uranium ultra-trace content, performed at the LNGS Chemistry Laboratory by High Resolution Mass Spectrometry (HR ICP MS), for the selection of all materials involved in the construction of the veto system

  6. ICP MS selection of radiopure materials for the GERDA experiment

    Energy Technology Data Exchange (ETDEWEB)

    Di Vacri, M. L., E-mail: divacrim@lngs.infn.it [INFN, Laboratori Nazionali del Gran Sasso, via G.Acitelli 22, 67100 Assergi (Italy); Dipartimento di Scienze Fisiche e Chimiche, University of L’Aquila, via Vetoio, 67100 L’Aquila (Italy); Nisi, S., E-mail: nisi@lngs.infn.it [INFN, Laboratori Nazionali del Gran Sasso, via G.Acitelli 22, 67100 Assergi (AQ) (Italy); Cattadori, C., E-mail: cattadori@lngs.infn.it [INFN Sezione di Milano Bicocca, Milano (Italy); Janicsko, J. [TUM Munich (Germany); Lubashevskiy, A. [MPIK, Heidelberg (Germany); JINR, Dubna (Russian Federation); Smolnikov, A. [MPIK, Heidelberg (Germany); Walter, M. [Physik-Institut, Universitat Zurich, 8057 Zurich (Switzerland)

    2015-08-17

    The GERDA (GERmanium Detector Array) experiment, located in the Gran Sasso Underground Laboratory (LNGS, Italy) aims to search for neutrinoless double beta (0νββ) decay of the {sup 76}Ge isotope. Both an ultra-low radioactivity background environment and active techniques to abate the residual background are required to reach the background index (of 10{sup −3} counts/keV kg y) at the Q{sub ββ}. In order to veto and suppress those events that partially deposit energy in Ge detectors, the readout of liquid argon (LAr) scintillation light (SL) has been implemented for the second GERDA experimental Phase. A double veto system has been designed and constructed using highly radiopure materials (scintillating fibers, wavelength shifters, polymeric foils, reflective foils). This work describes the study of lead, thorium and uranium ultra-trace content, performed at the LNGS Chemistry Laboratory by High Resolution Mass Spectrometry (HR ICP MS), for the selection of all materials involved in the construction of the veto system.

  7. Selection of steam generator materials for sodium cooled fast breeders

    International Nuclear Information System (INIS)

    Berge, P.

    1977-01-01

    The sodium water heat exchangers are now considered as the stumbling block in the development of liquid metal cooled fast breeders, due to the risk of sodium-water reactions. The selection of the materials for these tube-bundles has been very broad, for the different existing, or in-project, reactors in the world: low alloy 2 1/4 Cr - 1 Mo steels (unstabilized or stabilized); 9 Cr - 1 Mo ferritic steel; 18 Cr - 10 Ni austenitic stainless steels; alloy 800. On can also add other ferritic steels, as 9 Cr - 2 Mo stabilized, which are studied for this application. In the framework of the E.D.F.-C.E.A. working group a major effort was undertaken to study the characteristics of these various materials with respect to the main criteria governing construction of the tube bundles and their performance in service: mechanical characteristics at high temperature; fabrication and welding; behavior with respect to mass transfer in sodium; carburization and decarburization; corrosion resistance. The main lines and results of this program are described [fr

  8. Selective laser sintering of calcium phosphate materials for orthopedic implants

    Science.gov (United States)

    Lee, Goonhee

    Two technologies, Solid Freeform Fabrication (SFF) and bioceramics are combined in this work to prepare bone replacement implants with complex geometry. SFF has emerged as a crucial technique for rapid prototyping in the last decade. Selective Laser Sintering (SLS) is one of the established SFF manufacturing processes that can build three-dimensional objects directly from computer models without part-specific tooling or human intervention. Meanwhile, there have been great efforts to develop implantable materials that can assist in regeneration of bone defects and injuries. However, little attention has been focused in shaping bones from these materials. The main thrust of this research was to develop a process that can combine those two separate efforts. The specific objective of this research is to develop a process that can construct bone replacement material of complex geometry from synthetic calcium phosphate materials by using the SLS process. The achievement of this goal can have a significant impact on the quality of health care in the sense that complete custom-fit bone and tooth structures suitable for implantation can be prepared within 24--48 hours of receipt of geometric information obtained either from patient Computed Tomographic (CT) data, from Computer Aided Design (CAD) software or from other imaging systems such as Magnetic Resonance Imaging (MRI) and Holographic Laser Range Imaging (HLRI). In this research, two different processes have been developed. First is the SLS fabrication of porous bone implants. In this effort, systematic procedures have been established and calcium phosphate implants were successfully fabricated from various sources of geometric information. These efforts include material selection and preparation, SLS process parameter optimization, and development of post-processing techniques within the 48-hour time frame. Post-processing allows accurate control of geometry and of the chemistry of calcium phosphate, as well as

  9. Eestikeelseid filosoofiaraamatuid oodates / Leo Luks, Margus Ott

    Index Scriptorium Estoniae

    Luks, Leo, 1976-

    2016-01-01

    Möödunud aastal ilmus kaks algupärast eestikeelset filosoofiamonograafiat - Margus Oti "Vägi" ja Leo Luksi "Nihilism ja kirjandus". Nende autorid arutlevad vestluses, miks on filosoofiaraamatuid nii vähe

  10. Guidelines for the Development of Instructional Materials Selection Policies. Handbook I.

    Science.gov (United States)

    Motomatsu, Nancy, Ed.

    This manual was developed to assist school district personnel in the development of policies and procedures for selecting instructional materials. The manual describes State of Washington laws and regulations that govern the selection, use, and disposal of instructional materials and presents criteria and guidelines for selecting materials. Also…

  11. Composite materials pipings: selection of basic materials and manufacturing process, quality control during manufacture

    International Nuclear Information System (INIS)

    Pays, M.F.

    1997-01-01

    The purpose of the paper is to present a summary of the knowledge acquired at the R and D on resins used as composite matrix, the resistance to hydrolysis and mechanical strength of pipings made from these materials, and on quality control during manufacture. The initial targets concerning the material selection, industrial manufacturing and quality control procedures are presented. The paper describes the results obtained concerning the investigation of the damage produced by hydrolysis in polyesters, vinyl esters and epoxides, the influence of temperature, reinforcement and the mechanical characterization of the tubing manufacturing. The performances of the nondestructive testings (radiography, ultrasonic controls, differential interferometry and infrared thermography) used are also reported. The paper ends with a further research and testings programme. (author)

  12. The Resolved Stellar Population of Leo A

    Science.gov (United States)

    Tolstoy, Eline

    1996-05-01

    New observations of the resolved stellar population of the extremely metal-poor Magellanic dwarf irregular galaxy Leo A in Thuan-Gunn r, g, i, and narrowband Hα filters are presented. Using the recent Cepheid variable star distance determination to Leo A by Hoessel et al., we are able to create an accurate color-magnitude diagram (CMD). We have used the Bavesian inference method described by Tolstoy & Saha to calculate the likelihood of a Monte Carlo simulation of the stellar population of Leo A being a good match to the data within the well understood errors in the data. The magnitude limits on our data are sensitive enough to look back at ~1 Gyr of star formation history at the distance of Leo A. To explain the observed ratio of red to blue stars in the observed CMD, it is necessary to invoke either a steadily decreasing star formation rate toward the present time or gaps in the star formation history. We also compare the properties of the observed stellar population with the known spatial distribution of the H I gas and H II regions to support the conclusions from CMD modeling. We consider the possibility that currently there is a period of diminished star formation in Leo A, as evidenced by the lack of very young stars in the CMD and the faint H II regions. How the chaotic H I distribution, with no observable rotation, fits into our picture of the evolution of Leo A is as yet unclear.

  13. Studies on selected polymeric materials using the photoacoustic spectroscopic technique

    International Nuclear Information System (INIS)

    Singh, Hukum

    2011-01-01

    Polymethylmethacrylate—graft—polybisphenol—A-carbonate (PMMA-G-PC) with 50% grafting is synthesized. The graft co-polymerization of methylmethacrylate (0.036 mol · lit −1 ) onto polybisphenol—A-carbonate (0.5 g) in the presence of a redox couple formed from potassium persulphate (40 mol · lit −1 ) and thio-urea (30 mmol · lit −1 ) in aqueous nitric acid (0.18 M, 100 ml) in air at (45±2) °C for 3.0 h. Condensation of (PMMA-G-PC) with N- [p-(carboxyl phenyl amino acetic acid)] hydrazide (PCPH) affords polybisphenol-A-carbonate-graft-polymethylmethacrylate hydrazide (PCGH). The photoacoustic (PA) spectra of (PCGH) are recorded in a wavelength range from 200 nm to 800 nm at a modulation frequency of 22 Hz, and compared with those of pure polybisphenol-A-carbonate (PC), (PMMA-G-PC) and (PCPH). In the present work, a non-destructive and non-contact analytical method, namely the photoacoustic technique, is successfully implemented for optical and thermal characterization of selected polymeric materials. The indigenous PA spectrometer used in the present study consists of a 300-W xenon arc lamp, a lock-in amplifier, a chopper, a (1/8)-m monochromator controlled by computer and a home-made PA cell. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  14. Selective observation of charge storing ions in supercapacitor electrode materials.

    Science.gov (United States)

    Forse, Alexander C; Griffin, John M; Grey, Clare P

    2018-02-01

    Nuclear magnetic resonance (NMR) spectroscopy has emerged as a useful technique for probing the structure and dynamics of the electrode-electrolyte interface in supercapacitors, as ions inside the pores of the carbon electrodes can be studied separately from bulk electrolyte. However, in some cases spectral resolution can limit the information that can be obtained. In this study we address this issue by showing how cross polarisation (CP) NMR experiments can be used to selectively observe the in-pore ions in supercapacitor electrode materials. We do this by transferring magnetisation from 13 C nuclei in porous carbons to nearby nuclei in the cations ( 1 H) or anions ( 19 F) of an ionic liquid. Two-dimensional NMR experiments and CP kinetics measurements confirm that in-pore ions are located within Ångströms of sp 2 -hybridised carbon surfaces. Multinuclear NMR experiments hold promise for future NMR studies of supercapacitor systems where spectral resolution is limited. Copyright © 2017 University of Cambridge. Published by Elsevier Inc. All rights reserved.

  15. Surface Characteristics and Biofilm Development on Selected Dental Ceramic Materials

    Directory of Open Access Journals (Sweden)

    Kyoung H. Kim

    2017-01-01

    Full Text Available Background. Intraoral adjustment and polishing of dental ceramics often affect their surface characteristics, promoting increased roughness and consequent biofilm growth. This study correlated surface roughness to biofilm development with four commercially available ceramic materials. Methods. Four ceramic materials (Vita Enamic®, Lava™ Ultimate, Vitablocs Mark II, and Wieland Reflex® were prepared as per manufacturer instructions. Seventeen specimens of each material were adjusted and polished to simulate clinical intraoral procedures and another seventeen remained unaltered. Specimens were analysed by SEM imaging, confocal microscopy, and crystal violet assay. Results. SEM images showed more irregular surface topography in adjusted specimens than their respective controls. Surface roughness (Ra values were greater in all materials following adjustments. All adjusted materials with the exception of Vitablocs Mark II promoted significantly greater biofilm growth relative to controls. Conclusion. Simulated intraoral polishing methods resulted in greater surface roughness and increased biofilm accumulation.

  16. Key issues of multiple access technique for LEO satellite communication systems

    Institute of Scientific and Technical Information of China (English)

    温萍萍; 顾学迈

    2004-01-01

    The large carrier frequency shift caused by the high-speed movement of satellite (Doppler effects) and the propagation delay on the up-down link are very critical issues in an LEO satellite communication system, which affects both the selection and the implementation of a suitable access method. A Doppler based multiple access technique is used here to control the flow and an MPRMA-HS protocol is proposed for the application in LEO satellite communication systems. The extended simulation trials prove that the proposed scheme seems to be a very promising access method.

  17. Design of lightweight multi-material automotive bodies using new material performance indices of thin-walled beams for the material selection with crashworthiness consideration

    International Nuclear Information System (INIS)

    Cui, Xintao; Zhang, Hongwei; Wang, Shuxin; Zhang, Lianhong; Ko, Jeonghan

    2011-01-01

    Currently, automotive bodies are constructed usually using a single material, e.g. steel or aluminum. Compared to single-material automotive bodies, multi-material automotive bodies allow optimal material selection in each structural component for higher product performance and lower cost. This paper presents novel material performance indices and procedures developed to guide systematic material selection for multi-material automotive bodies. These new indices enable to characterize the crashworthiness performance of complex-shaped thin-walled beams in multi-material automotive bodies according to material types. This paper also illustrates the application of these performance indices and procedures by designing a lightweight multi-material automotive body. These procedures will help to design a lightweight and affordable body favored by the automotive industry, thus to reduce fuel consumption and greenhouse gas emissions.

  18. Assessment of the radiological impact of selected building materials

    International Nuclear Information System (INIS)

    Gwiazdowski, B.

    1983-02-01

    Naturally occurring radionuclides in building materials are a source of external and internal radiation exposure to essentially the entire Polish population. The programme of our studies met two main aspects on radioactivity of building materials: Gamma dose rate and radon or alpha potential energy concentration measurements in dwellings of various kinds of structure and materials in both industrial and rural districts of Poland. Gamma dose rate measurements were made in about 2200 dwellings and radon or alpha potential energy concentration measurements - in 750 dwellings. On the basis of these studies the annual effective dose equivalent to the Polish population due to gamma and alpha radiation indoors was estimated to be 0.39 mSv/a and 0.99 mSv/a, respectively. The contribution of external (from gamma) and internal (from alpha) radiation exposure due to naturally occurring radionuclides in building materials to the total radiation exposure of Polish population was assessed to be 3.6 per cent and 34.2 per cent, respectively. Measurements of about 1500 samples of various kinds of building materials and raw materials were made to determine radionuclide concentrations in them. The highest values were obtained in samples of phosphogypsum, fly ash and slag: potassium concentration ranges up to 36 pCi g -1 (a slag sample), radium - up to 17 pCi g -1 (a phosphogypsum sample) and thorium - up to 4 pCi g -1 (a phosphogypsum). On the basis of the results of our studies we came to the conclusion that it was necessary to work out a control system which could protect habitants against enhancement of indoor exposure to ionizing radiation

  19. Towards 'selection rules' in the radiation chemistry of molecular materials

    International Nuclear Information System (INIS)

    Feldman, V.I.; Inst. of Synthetic Polymetric Materials, Moscow; Moscow State Univ.

    2002-01-01

    Complete text of publication follows. There are a lot of experimental evidences suggesting that the primary radiation-induced events in organic solids and polymers are highly selective and sensitive to conformation, molecular packing, matrix environment, etc. Nevertheless, specific 'selection rules' in the radiation chemistry of molecules in solids are still not established. This contribution presents a review of our recent studies of the radiation damage in organic molecules in low-temperature matrices and polymers aimed at elucidation of basic physical factors controlling selectivity of the primary chemical events. The following aspects will be analyzed: 1. 'Fine tuning' effects in positive hole trapping in rigid systems containing molecular 'traps' with close ionization energy. 2. Selective chemical bond weakening in ionized molecules: experimental and theoretical results. 3. Matrix-assisted and matrix-controlled chemical reactions of ionized molecules in solid media (including the effect of 'matrix-catalysis'). 4. Effect of excess energy on the fate of ionized molecules in solid matrices: the role of intramolecular and intermolecular relaxation. Finally, the problem of experimental and theoretical simulation of the distribution of the radiation-induced events in complex molecular systems and polymers will be addressed

  20. Use of selected waste materials in concrete mixes.

    Science.gov (United States)

    Batayneh, Malek; Marie, Iqbal; Asi, Ibrahim

    2007-01-01

    A modern lifestyle, alongside the advancement of technology has led to an increase in the amount and type of waste being generated, leading to a waste disposal crisis. This study tackles the problem of the waste that is generated from construction fields, such as demolished concrete, glass, and plastic. In order to dispose of or at least reduce the accumulation of certain kinds of waste, it has been suggested to reuse some of these waste materials to substitute a percentage of the primary materials used in the ordinary portland cement concrete (OPC). The waste materials considered to be recycled in this study consist of glass, plastics, and demolished concrete. Such recycling not only helps conserve natural resources, but also helps solve a growing waste disposal crisis. Ground plastics and glass were used to replace up to 20% of fine aggregates in concrete mixes, while crushed concrete was used to replace up to 20% of coarse aggregates. To evaluate these replacements on the properties of the OPC mixes, a number of laboratory tests were carried out. These tests included workability, unit weight, compressive strength, flexural strength, and indirect tensile strength (splitting). The main findings of this investigation revealed that the three types of waste materials could be reused successfully as partial substitutes for sand or coarse aggregates in concrete mixtures.

  1. Use of selected waste materials in concrete mixes

    International Nuclear Information System (INIS)

    Batayneh, Malek; Marie, Iqbal; Asi, Ibrahim

    2007-01-01

    A modern lifestyle, alongside the advancement of technology has led to an increase in the amount and type of waste being generated, leading to a waste disposal crisis. This study tackles the problem of the waste that is generated from construction fields, such as demolished concrete, glass, and plastic. In order to dispose of or at least reduce the accumulation of certain kinds of waste, it has been suggested to reuse some of these waste materials to substitute a percentage of the primary materials used in the ordinary portland cement concrete (OPC). The waste materials considered to be recycled in this study consist of glass, plastics, and demolished concrete. Such recycling not only helps conserve natural resources, but also helps solve a growing waste disposal crisis. Ground plastics and glass were used to replace up to 20% of fine aggregates in concrete mixes, while crushed concrete was used to replace up to 20% of coarse aggregates. To evaluate these replacements on the properties of the OPC mixes, a number of laboratory tests were carried out. These tests included workability, unit weight, compressive strength, flexural strength, and indirect tensile strength (splitting). The main findings of this investigation revealed that the three types of waste materials could be reused successfully as partial substitutes for sand or coarse aggregates in concrete mixtures

  2. Inkjet Printing of Functional Materials on Selectively Plasma Treated Surfaces

    NARCIS (Netherlands)

    ir Martijn van Dongen; ir Renee Verkuijlen; Dr Jan Bernards

    2011-01-01

    In manufacturing of organic electronics, inkjet printing as an alternative technique for depositing materials is becoming increasingly important. Aside to the ink formulations challenges, improving the resolution of the printed patterns is a major goal. In this study we will discuss a newly

  3. 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…

  4. Challenging Christianity: Leo Tolstoy and Religious Education

    Science.gov (United States)

    Moulin, Dan

    2009-01-01

    The religious thought of Russian novelist Leo Tolstoy is a well documented but often overlooked example of unorthodox Christianity. This paper uses the example of Tolstoy's religious thinking to question the integrity of the current representation of Christianity in UK schools. It also uses Tolstoy's criticism of orthodox Christianity to suggest a…

  5. Nanostructured materials for selective recognition and targeted drug delivery

    International Nuclear Information System (INIS)

    Kotrotsiou, O; Kotti, K; Dini, E; Kammona, O; Kiparissides, C

    2005-01-01

    Selective recognition requires the introduction of a molecular memory into a polymer matrix in order to make it capable of rebinding an analyte with a very high specificity. In addition, targeted drug delivery requires drug-loaded vesicles which preferentially localize to the sites of injury and avoid uptake into uninvolved tissues. The rapid evolution of nanotechnology is aiming to fulfill the goal of selective recognition and optimal drug delivery through the development of molecularly imprinted polymeric (MIP) nanoparticles, tailor-made for a diverse range of analytes (e.g., pharmaceuticals, pesticides, amino acids, etc.) and of nanostructured targeted drug carriers (e.g., liposomes and micelles) with increased circulation lifetimes. In the present study, PLGA microparticles containing multilamellar vesicles (MLVs), and MIP nanoparticles were synthesized to be employed as drug carriers and synthetic receptors respectively

  6. Experimental Observations on Dynamic Response of Selected Transparent Armor Materials

    Science.gov (United States)

    2014-07-01

    Monolithic single crystal sapphire plates (100×100× 10 mm), from GT Crystal Systems, Inc., Salem , MA, in crystallographically controlled directions...Future Army Applications (2011) The National Academies Press , Washington, D.C. 5. Graff KF (1991) Wave motion in elastic solids, Dover Publications 6...2004) Visualization of impact damage in ceramics using the edge-on impact technique. Int J Appl Ceram Technol 1 (3):235–242 Fig. 38 Selection of a

  7. Improving the sun drying of apricots (Prunus armeniaca) with photo-selective dryer cabinet materials

    Science.gov (United States)

    Photo-selective materials have been studied for their effects on the pre-harvest quality of horticultural crops, but little work has been done on potential post-harvest effects. The aim of this work was to characterize the effects of 5 different photo-selective acrylic materials (used as the lid to...

  8. Optimal selection for shielding materials by fuzzy linear programming

    International Nuclear Information System (INIS)

    Kanai, Y.; Miura, N.; Sugasawa, S.

    1996-01-01

    An application of fuzzy linear programming methods to optimization of a radiation shield is presented. The main purpose of the present study is the choice of materials and the search of the ratio of mixture-component as the first stage of the methodology on optimum shielding design according to individual requirements of nuclear reactor, reprocessing facility, shipping cask installing spent fuel, ect. The characteristic values for the shield optimization may be considered their cost, spatial space, weight and some shielding qualities such as activation rate and total dose rate for neutron and gamma ray (includes secondary gamma ray). This new approach can reduce huge combination calculations for conventional two-valued logic approaches to representative single shielding calculation by group-wised optimization parameters determined in advance. Using the fuzzy linear programming method, possibilities for reducing radiation effects attainable in optimal compositions hydrated, lead- and boron-contained materials are investigated

  9. Pelamis WEC - main body structural design and materials selection

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, C.

    2003-07-01

    This report summarises the results of a study evaluating the potential use of rolled steel, glass reinforced plastic, wood-epoxy laminate, and different forms of concrete as primary structural materials for the Pelamis Wave Energy Converter (WEC) as part of a strategy to refine the design by highlighting cost savings for long-term manufacture. Details are given of the drawing up of a load spectrum in order to assess the candidate structures, the choice of glass reinforced plastic, concrete, and steel for further evaluation based on preliminary screening, the assessment of the material requirements for each candidate structure, and cost estimates. The advantages of the use of concrete are discussed and recommendations are presented.

  10. Corrosion behavior of materials selected for FMIT lithium system

    International Nuclear Information System (INIS)

    Bazinet, G.D.; Down, M.G.; Matlock, D.K.

    1983-01-01

    The corrosion program consisted of a multi-disciplinary approach utilizing the liquid lithium test resources and capabilities of several laboratories. Specific concerns associated with the overall objective of materials corrosion behavior were evaluated at each laboratory. Testing conditions included: approx. 3700 hours of exposure to flowing lithium at temperatures from 230 0 C to 270 0 C and approx. 6500 hours of exposure to flowing lithium at an isothermal temperature of 270 0 C. Principal areas of investigation, to be discussed here briefly, included lithium corrosion effects on the following: (1) types 304 and 304L austenitic stainless steels, which are specified as reference materials for the FMIT lithium system; (2) type 304 stainless steel weldments (w/type 308 stainless steel filler) typical of specified tube and butt welds in the lithium system design; (3) titanium, zirconium and yttrium, which represent potential hot trap getter materials; (4) BNi4 braze alloy, used as a potential attachement method in the plug/seat fabrication of liquid lithium valves; and (5) type 321 stainless steel bellows, typical of bellows used in potential liquid lithium valve designs

  11. Corrosion behavior of materials selected for FMIT lithium system

    Energy Technology Data Exchange (ETDEWEB)

    Bazinet, G.D.; Down, M.G.; Matlock, D.K.

    1983-01-01

    The corrosion program consisted of a multi-disciplinary approach utilizing the liquid lithium test resources and capabilities of several laboratories. Specific concerns associated with the overall objective of materials corrosion behavior were evaluated at each laboratory. Testing conditions included: approx. 3700 hours of exposure to flowing lithium at temperatures from 230/sup 0/C to 270/sup 0/C and approx. 6500 hours of exposure to flowing lithium at an isothermal temperature of 270/sup 0/C. Principal areas of investigation, to be discussed here briefly, included lithium corrosion effects on the following: (1) types 304 and 304L austenitic stainless steels, which are specified as reference materials for the FMIT lithium system; (2) type 304 stainless steel weldments (w/type 308 stainless steel filler) typical of specified tube and butt welds in the lithium system design; (3) titanium, zirconium and yttrium, which represent potential hot trap getter materials; (4) BNi4 braze alloy, used as a potential attachement method in the plug/seat fabrication of liquid lithium valves; and (5) type 321 stainless steel bellows, typical of bellows used in potential liquid lithium valve designs.

  12. Study on Material Selection of Reactor Pressure Vessel of SCWR

    Science.gov (United States)

    Ma, Shuli; Luo, Ying; Yin, Qinwei; Li, Changxiang; Xie, Guofu

    This paper first analyzes the feasibility of SA-508 Grade 3 Class 1 Steel as an alternative material for Supercritical Water-Cooled Reactor (SCWR) Reactor Pressure Vessel (RPV). This kind of steel is limited to be applied in SCWR RPV due to its quenching property, though large forging could be accomplished by domestic manufacturers in forging aspect. Therefore, steels with higher strength and better quenching property are needed for SWCR RPV. The chemical component of SA-508 Gr.3 Cl.2 steel is similar to that of SA-508 Gr.3 Cl.1 steel, and more appropriate matching of strength and toughness could be achieved by the adjusting the elements contents, as well as proper control of tempering temperature and time. In light of the fact that Cl.2 steel has been successfully applied to steam generator, it could be an alternative material for SWCR RPV. SA-508 Gr.4N steel with high strength and good toughness is another alternative material for SCWR RPV. But large amount of research work before application is still needed for the lack of data on welding and irradiation etc.

  13. Preliminary selection criteria for the Yucca Mountain Project waste package container material

    International Nuclear Information System (INIS)

    Halsey, W.G.

    1991-01-01

    The Department of Energy's Yucca Mountain Project (YMP) is evaluating a site at Yucca Mountain in Nevada for construction of a geologic repository for the storage of high-level nuclear waste. Lawrence Livermore National Laboratory's (LLNL) Nuclear Waste Management Project (NWMP) has the responsibility for design, testing, and performance analysis of the waste packages. The design is performed in an iterative manner in three sequential phases (conceptual design, advanced conceptual design, and license application design). An important input to the start of the advanced conceptual design is the selection of the material for the waste containers. The container material is referred to as the 'metal barrier' portion of the waste package, and is the responsibility of the Metal Barrier Selection and Testing task at LLNL. The selection will consist of several steps. First, preliminary, material-independent selection criteria will be established based on the performance goals for the container. Second, a variety of engineering materials will be evaluated against these criteria in a screening process to identify candidate materials. Third, information will be obtained on the performance of the candidate materials, and final selection criteria and quantitative weighting factors will be established based on the waste package design requirements. Finally, the candidate materials will be ranked against these criteria to determine whether they meet the mandated performance requirements, and to provide a comparative score to choose the material for advanced conceptual design activities. This document sets forth the preliminary container material selection criteria to be used in screening candidate materials. 5 refs

  14. Next Generation Nuclear Plant Materials Selection and Qualification Program Plan

    Energy Technology Data Exchange (ETDEWEB)

    R. Doug Hamelin; G. O. Hayner

    2004-11-01

    The U.S. Department of Energy (DOE) has selected the Very High Temperature Reactor (VHTR) design for the Next Generation Nuclear Plant (NGNP) Project. The NGNP will demonstrate the use of nuclear power for electricity and hydrogen production without greenhouse gas emissions. The reactor design is a graphite-moderated, helium-cooled, prismatic or pebble bed thermal neutron spectrum reactor with an average reactor outlet temperature of at least 1000 C. The NGNP will use very high burn up, lowenriched uranium, TRISO-Coated fuel in a once-through fuel cycle. The design service life of the NGNP is 60 years.

  15. Materials Selection and Their Characteristics as Used in Rapid Prototyping

    Science.gov (United States)

    Cooper, K.; Salvail, P.; Vesely, E.; Wells, D.

    1999-01-01

    NASA's Marshall Space Flight Center (MSFC) conducted a program to evaluate six technologies used in Rapid Prototyping (RP) to produce investment casting patterns. In this paper, RP refers to the collective additive fabrication technologies known as Solid Free-Form Fabrication. Such technologies are being used with increasing frequency in manufacturing applications, due in part to their rapidly expanding capabilities to fabricate models from many types of materials. This study used ABS plastic, polycarbonate, TrueForm PM6, epoxy resin, paper, starch, and wax. The baseline model was a semi-complex prototype fuel pump housing, intended for use in the X-33 reusable launch vehicle. All models were shelled in a production- grade colloidal silica ceramic. Primary coats were zircon-base flour with zircon backup, while secondary coats were silica grains with a tabular alumina backup. Each model was shelled in an identical manner, using the same atmospheric conditions and drying times, as well as the same number of layers. Bake-outs and firing cycles were consistent with the leach ability of each material. Preheat and bath temperatures were also kept consistent. All molds were cast in vacuum using a hydrogen-resistant superalloy (NASA- 23) that was developed in-house. The final technical evaluation included detailed measurements of the model and the final casting, in order to determine any dimensional changes caused by different pattern materials, as well as documentation of all defects and any obvious refractory/model reactions. Prototype production costs were estimated for each method and taken into consideration during trade-off analysis.

  16. Materials selection in micromechanical design: an application of the Ashby approach

    OpenAIRE

    Srikar, V.T.; Spearing, S.M.

    2003-01-01

    The set of materials available to microsystems designers is rapidly expanding. Techniques now exist to introduce and integrate a large number of metals, alloys, ceramics, glasses, polymers, and elastomers into microsystems, motivating the need for a rational approach for materials selection in microsystems design. As a step toward such an approach, we focus on the initial stages of materials selection for micromechanical structures with minimum feature sizes greater than 1 /spl mu/m. The vari...

  17. An overview of safety and environmental considerations in the selection of materials for fusion facilities

    International Nuclear Information System (INIS)

    Petti, D.A.; Piet, S.J.; Seki, Y.

    1996-01-01

    Safety and environmental considerations can play a large role in the selection of fusion materials. In this paper, we review the attributes of different structural, plasma facing, and breeding materials from a safety perspective and discuss some generic waste management issues as they relate to fusion materials in general. Specific safety concerns exist for each material that must be dealt with in fusion facility design. Low activation materials offer inherent safety benefits compared with conventional materials, but more work is needed before these materials have the requisite certified databases. In the interim, the international thermonuclear experimental reactor (ITER) has selected more conventional materials and is showing that the safety concerns with these materials can be addressed by proper attention to design. In the area of waste management disposal criteria differ by country. However, the criteria are all very strict making disposal of fusion components difficult. As a result, recycling has gained increasing attention. (orig.)

  18. New membrane materials for potassium-selective ion-sensitive field-effect transistors

    NARCIS (Netherlands)

    van der Wal, P.D.; van der Wal, Peter D.; Skowronska-Ptasinska, Maria; van den Berg, Albert; Bergveld, Piet; Sudholter, Ernst; Sudholter, Ernst J.R.; Reinhoudt, David

    1990-01-01

    Several polymeric materials were studied as membrane materials for potassium-selective ion-sensitive field-effect transistors (ISFETs) to overcome the problems related with the use of conventional plasticized poly(vinyl chloride) membranes casted on ISFET gate surfaces. Several acrylate materials,

  19. Status of international collaborative efforts on selected ITER materials

    International Nuclear Information System (INIS)

    Belyakov, V.A.; Fabritsiev, S.A.; Mazul, I.V.; Rowcliffe, A.F.

    2000-01-01

    The paper presents an overview of the performance of refractory metals, beryllium, and copper alloys, for the international thermonuclear experimental reactor (ITER) high heat flux structures. High temperature brazing, hot isostatic pressing (HIP), friction welding, explosive bonding, and other methods were explored to join copper alloys to 316 stainless steel for first wall and limiter applications. It is concluded that the main material problems for the ITER high heat flux components are: (a) degradation of properties after the manufacturing cycle (especially for Be/Cu and Cu/stainless steel (SS) joints); (b) helium embrittlement of Be, and Cu, and; (c) radiation-induced loss of fracture toughness for Be, W, and Cu alloys

  20. Decommissioning Strategies Selection for Facilities Using Radioactive Material

    International Nuclear Information System (INIS)

    Husen Zamroni; Jaka Rachmadetin

    2008-01-01

    The facilities using radioactive material that have been stopped operation will require some form of the decommissioning for public and environment safety. The approaches are identified by three decommissioning strategies: immediate dismantling, deferred dismantling and entombment. If a facility undergoes immediate dismantling, most radio nuclides will have no such sufficient time to decay and therefore this strategy may not provide reduction in the worker exposure. A facility that undergoes deferred dismantling may advantage from the radioactive decay of residual radio nuclides during the long term storage period and entombment could be a viable option for other nuclear facilities containing only short lived or limited concentrations of long lived radionuclides. Mostly, only two types of the decommissioning used to be done in the world, immediate and deferred dismantling. (author)

  1. Selection of Corrosion Resistant Materials for Nuclear Waste Repositories

    International Nuclear Information System (INIS)

    R.B. Rebak

    2006-01-01

    Several countries are considering geological repositories to dispose of nuclear waste. The environment of most of the currently considered repositories will be reducing in nature, except for the repository in the US, which is going to be oxidizing. For the reducing repositories, alloys such as carbon steel, stainless steels and titanium are being evaluated. For the repository in the US, some of the most corrosion resistant commercially available alloys are being investigated. This paper presents a summary of the behavior of the different materials under consideration for the repositories and the current understanding of the degradation modes of the proposed alloys in ground water environments from the point of view of general corrosion, localized corrosion and environmentally assisted cracking

  2. Updating Classifications of Ceramic Dental Materials: A Guide to Material Selection.

    Science.gov (United States)

    McLaren, Edward A; Figueira, Johan

    2015-06-01

    The indications for and composition of today's dental ceramic materials serve as the basis for determining the appropriate class of ceramics to use for a given case. By understanding the classifications, composition, and characteristics of the latest all-ceramic materials, which are presented in this article in order of most to least conservative, dentists and laboratory technicians can best determine the ideal material for a particular treatment.

  3. Wave Optics Based LEO-LEO Radio Occultation Retrieval

    DEFF Research Database (Denmark)

    von Benzon, Hans-Henrik; Høeg, Per

    2016-01-01

    of the atmospheric products such as the correct water vapor content in the atmosphere. These limitations can be overcome when a proper selected range of high frequency waves are used to probe the atmosphere. Probing frequencies close to the absorption line of water vapor have been included, thus allowing...... the retrieval of the water vapor content. Selecting the correct probing frequencies would make it possible to retrieve other information such as the content of ozone. The retrieval is performed through a number of processing steps which are based on the Full Spectrum Inversion (FSI) technique. The retrieval...... optics based retrieval chain is used on a number of examples and the retrieved atmospheric parameters are compared to the parameters from a global ECMWF analysis model. This model is used in a forward propagator that simulates the electromagnetic field amplitudes and phases at the receiver on board...

  4. Application of GRA for Sustainable Material Selection and Evaluation Using LCA

    Science.gov (United States)

    Jayakrishna, Kandasamy; Vinodh, Sekar; Sakthi Sanghvi, Vijayaselvan; Deepika, Chinadurai

    2016-07-01

    Material selection is identified as a successful key parameter in establishing any product to be sustainable, considering its end of life (EoL) characteristics. An accurate understanding of expected service conditions and environmental considerations are crucial in the selection of material plays a vital role with overwhelming customer expectations and stringent laws. Therefore, this article presents an integrated approach for sustainable material selection using grey relational analysis (GRA) considering the EoL disposal strategies with respect to an automotive product. GRA, an impact evaluation model measures the degree of similarity between the comparability (choice of material) sequence and reference (EoL strategies) sequence based on the relational grade. The ranking result shows that the outranking relationships in the order, ABS-REC > PP-INC > AL-REM > PP-LND > ABS-LND > ABS-INC > PU-LND > AL-REC > AL-LND > PU-INC > AL-INC. The best sustainable material selected was ABS and recycling was selected as the best EoL strategy with the grey relational value of 2.43856. The best material selected by this approach, ABS was evaluated for its viability using life cycle assessment and the estimated impacts also proved the practicability of the selected material highlighting the focus on dehumidification step in the manufacturing of the case product using this developed multi-criteria approach.

  5. Tunable Impedance Spectroscopy Sensors via Selective Nanoporous Materials.

    Energy Technology Data Exchange (ETDEWEB)

    Nenoff, Tina M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Small, Leo J [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-09-01

    Impedance spectroscopy was leveraged to directly detect the sorption of I 2 by selective adsorption into nanoporous metal organic frameworks (MOF). Films of three different types of MOF frameworks, respectively, were drop cast onto platinum interdigitated electrodes, dried, and exposed to gaseous I 2 at 25, 40, or 70 C. The MOF frameworks varied in topology from small pores (equivalent to I 2 diameter) to large pore frameworks. The combination of the chemistry of the framework and pore size dictated quantity and kinetics of I 2 adsorption. Air, argon, methanol, and water were found to produce minimal changes in ZIF-8 impedance. Independent of MOF framework characteristics, all resultant sensors showed high response to I 2 in air. As an example of sensor output, I 2 was readily detected at 25 C in air within 720 s of exposure, using an un-optimized sensor geometry with a small pored MOF. Further optimization of sensor geometry, decreasing MOF film thicknesses and maximizing sensor capacitance, will enable faster detection of trace I 2 .

  6. Production of Biofuels from Selected Cellulosic Waste materials

    Directory of Open Access Journals (Sweden)

    Jathwa Abdul Kareem Ibrahim

    2017-08-01

    Full Text Available In this study four types of cellulose-rich municipal solid wastes (residuals of orange, banana peel, corn residues, and saw dust were used as raw materials. These cellulosic substrates usually have a lot of lignin content which prevents the process of saccharification by microorganisms. Thus pretreatment methods of enzymatic, acid or base with enzymatic treatment and dilute acid followed by autoclaving were necessary to dignify these wastes and to obtain higher reducing sugar yields and hence higher ethanol production. Dilute HCl acid of 1% followed by autoclaving at 121℃ for 30 min proved to give good result where significant amounts of reducing sugars were obtained at the end of the saccharification process. Orange peel proved to give the highest glucose concentration of an average of 6000 mg/l on day 4 of the saccharification process. Fermentation was carried out for the hydrolyzed samples using Saccharomyces cerevisiae yeast. The amount of ethanol produced after fermentation was found to be the highest for orange peel having a value of 1300 mg/l after 96h of incubation. As science is proceeding, engineered microorganisms could help to produce sustainable fuels from cellulose-rich municipal solid wastes in the future.

  7. Characterization of hydrotalcite materials for CO2 selective membranes

    Energy Technology Data Exchange (ETDEWEB)

    Feuillade, V.C.; Haije, W.G. [ECN Hydrogen and Clean Fossil Fuels, Petten (Netherlands)

    2006-07-15

    The present concern about climate change has urged researchers and engineers all over the world to go and look for ways of reducing greenhouse gas emissions. Largescale CO2 emissions occur at power plants burning fossil fuels or e.g. the production of hydrogen from carbonaceous feed. In these cases pre- or post-combustion CO2 capture techniques followed by CO2 storage seems a promising route for reducing emissions. Prerequisite in these processes is the effective separation of CO2 from mixed gaseous process streams. The purpose of this work is to develop CO2 membranes to allow for the combination of natural gas reforming with separation of H2 and CO2 in separation enhanced reactors, i.e. membrane reactors, for carbon-free hydrogen production or electricity generation. This paper describes the materials' properties of hydrotalcites, a promising class of compounds for CO2 membranes. They have already proven their applicability as CO2 sorbent in sorption enhanced reaction processes. It is of fundamental importance to know the structural stability of this compound in the operational window of a chosen membrane reactor prior to any membrane fabrication. To this end, in-situ XRPD and DRIFTS as well as TGA-MS and SEM-EDX measurements have been performed on commercial (Pural) and hydrothermally synthesized homemade samples.

  8. 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.

  9. Charged particle and laser irradiation of selected materials

    International Nuclear Information System (INIS)

    Svendsen, W.E.

    1996-11-01

    The main topics of the present thesis are the processes governing electronic sputtering of insulators and laser ablation of metals and insulators. The sputtering yield for electron bombardment of solid deuterium was investigated using quartz crystal microbalances as the measuring technique. The sputtering yield was measured with varying electron energy and deuterium film thickness. Laser ablation measurements of silver and nickel were carried out using a Nd:YAG laser. The effect of various experimental parameters such as background gas pressure (Ar, N 2 ), position of quartz crystals with respect to target position and the optimal number of laser shots for carrying out the experiments were investigated. The deposition rate was measured with varying laser wavelength and laser fluence. The angular distribution of the ablated material was measured for silver as well. A theoretical model based on the thermal properties of laser interaction with metals was applied in the initial phase of ablation. For the non-thermal processes governing laser interaction with the ablated plasma plume, a model developed by Phipps and Dreyfus was used to interpret the results. Laser ablation measurements of water-ice were carried using a Nitrogen laser. Attempts were made to measure the deposition rate for various the laser wavelengths and energies. (au) 8 tabs., 49 ills., 77 refs

  10. Review of selected dynamic material control functions for international safeguards

    International Nuclear Information System (INIS)

    Lowry, L.L.

    1980-09-01

    With the development of Dynamic Special Nuclear Material Accounting and Control systems used in nuclear manufacturing and reprocessing plants, there arises the question as to how these systems affect the IAEA inspection capabilities. The systems in being and under development provide information and control for a variety of purposes important to the plant operator, the safeguards purpose being one of them. This report attempts to judge the usefulness of these dynamic systems to the IAEA and have defined 12 functions that provide essential information to it. If the information acquired by these dynamic systems is to be useful to the IAEA, the inspectors must be able to independently verify it. Some suggestions are made as to how this might be done. But, even if it should not be possible to verify all the data, the availability to the IAEA of detailed, simultaneous, and plant-wide information would tend to inhibit a plant operator from attempting to generate a floating or fictitious inventory. Suggestions are made that might be helpful in the design of future software systems, an area which has proved to be fatally deficient in some systems and difficult in all

  11. Charged particle and laser irradiation of selected materials

    Energy Technology Data Exchange (ETDEWEB)

    Svendsen, W E

    1996-11-01

    The main topics of the present thesis are the processes governing electronic sputtering of insulators and laser ablation of metals and insulators. The sputtering yield for electron bombardment of solid deuterium was investigated using quartz crystal microbalances as the measuring technique. The sputtering yield was measured with varying electron energy and deuterium film thickness. Laser ablation measurements of silver and nickel were carried out using a Nd:YAG laser. The effect of various experimental parameters such as background gas pressure (Ar, N{sub 2}), position of quartz crystals with respect to target position and the optimal number of laser shots for carrying out the experiments were investigated. The deposition rate was measured with varying laser wavelength and laser fluence. The angular distribution of the ablated material was measured for silver as well. A theoretical model based on the thermal properties of laser interaction with metals was applied in the initial phase of ablation. For the non-thermal processes governing laser interaction with the ablated plasma plume, a model developed by Phipps and Dreyfus was used to interpret the results. Laser ablation measurements of water-ice were carried using a Nitrogen laser. Attempts were made to measure the deposition rate for various the laser wavelengths and energies. (au) 8 tabs., 49 ills., 77 refs.

  12. Leo satellite-based telecommunication network concepts

    Science.gov (United States)

    Aiken, John G.; Swan, Peter A.; Leopold, Ray J.

    1991-01-01

    Design considerations are discussed for Low Earth Orbit (LEO) satellite based telecommunications networks. The satellites are assumed to be connected to each other via intersatellite links. They are connected to the end user either directly or through gateways to other networks. Frequency reuse, circuit switching, packet switching, call handoff, and routing for these systems are discussed by analogy with terrestrial cellular (mobile radio) telecommunication systems.

  13. Method for selecting raw materials to preparing ceramic masses: application to raw material for red ceramic

    International Nuclear Information System (INIS)

    Moreno, Maria Margarita Torres; Rocha, Rogers Raphael da; Zanard, Antenor

    2012-01-01

    We studied the raw materials used in a factory building blocks, located in Cesario Lange city (SP). It extracts raw materials from various sources in the region to make the dough. The mixtures were prepared from dry milled powders based on data related to the plasticity of the raw materials. It was obtained with the apparatus Vicat-cone in order to obtain similar levels of water absorption of the samples burned at 900 deg C for all compositions. To quantify the proportion of each clay was used the Lever Rule. In this firing temperature, where sintering is mainly by diffusion from a solid state, different compositions of the same set of four raw materials resulted in similar values. (author)

  14. An Augmented Common Weight Data Envelopment Analysis for Material Selection in High-tech Industries

    Directory of Open Access Journals (Sweden)

    Iman Shokr

    2016-08-01

    Full Text Available Material selection is a challenging issue in manufacturing processes while the inappropriate selected material may lead to fail the manufacturing process or end user experience especially in high-tech industries such as aircraft and shipping. Every material has different quantitative and qualitative criteria which should be considered simultaneously when assessing and selecting the right material. A weighted linear optimization method (WLOM in the class of data envelopment analysis which exists in literature is adopted to address material selection problem while accounting for both qualitative and quantitative criteria. However, it is demonstrated the adopted WLOM method is not able to produce a full ranking vector for the material selection problems borrowed from the literature. Thus, an augmented common weight data envelopment analysis model (ACWDEA is developed in this paper with the aim of eliminating deficiencies of WLOM model. The proposed ACWDEA is able to produce full ranking vector in decision making problems with less computational complexities in superior to the WLOM. Two material selection problems are solved and results are compared with WLOM and previous methods. Finally, the robustness and effectiveness of the proposed ACWDEA method are evaluated through Spearman’s correlation tests.

  15. The Selection of Materials for Roller Chains From The Perspective Of Manufacturing Process

    Directory of Open Access Journals (Sweden)

    Rahmat Saptono

    2010-10-01

    Full Text Available The selection of materials for an engineering component is not only requested by its design function and shape, but also the sequence through which it is manufactured. The manufacturing operation of roller chains involves drawing and trimming processes aimed at producing semi-finished chain drives component with a well-standardized dimension. In addition to final combination of properties required by design constraints, the ability of materials to be formed into a desired shape and geometry without failure is also critical. The objective of materials selection should therefore involve additional attributes that are not typically  accommodated by the standard procedure of materials selection. The present paper deals with the selection of materials for roller chains from the perspective of manufacturing process. Ears and un-uniform wall thickness have been identified as a key problem in the mass production of component. Provided all process parameters were established, the  anisotropy factor of materials is critical. Simulative test can be reasonably used to obtain material performance indices that can be added up to the standard procedure of material selection. Of three commercially available steel grades evaluated with regard to the criteria defined, one grade is more suitable for the present objective.

  16. Materials selection as an interdisciplinary technical activity: basic methodology and case studies

    Directory of Open Access Journals (Sweden)

    M. Ferrante

    2000-04-01

    Full Text Available The technical activity known as Materials Selection is reviewed in its concepts and methodologies. Objectives and strategies are briefly presented and two important features are introduced and discussed; (i Merit Indices: a combination of materials properties, which maximises the objectives chosen by the designer and (ii Materials Properties Maps: a bi-dimensional space whose coordinates are pairs of properties in which materials can be plotted and compared directly in terms of their merit indices. A general strategy for the deduction of these indices is explained and a formal methodology to establish a ranking of candidate materials when multiple constraints intervene is presented. Finally, two case studies are discussed in depth, one related to materials substitution in the context of mechanical design and a less conventional case linking material selection to physical comfort in the home furniture industry.

  17. Seletividade de cultivares de soja RR® submetidos a misturas em tanque de glyphosate + chlorimuron-ethyl associadas a óleo mineral e inseticidas selectivity of soybean RR® genotypes submitted to glyphosate + chlorimuron-ethyl tank mixtures associated to mineral oil and insecticides

    Directory of Open Access Journals (Sweden)

    C.D.G. Maciel

    2009-01-01

    Full Text Available O uso de glyphosate para o controle de plantas daninhas em soja RR® apresenta características essenciais no conceito de praticabilidade. Entretanto, apesar de não permitido na legislação brasileira, tem-se aumentado a associação com outros herbicidas para manejo de espécies de difícil controle, assim como a sua mistura em tanque em combinação com inseticidas e adjuvantes. Com o objetivo de avaliar a seletividade de cultivares de soja RR® submetidos a misturas em tanque de formulações de glyphosate (Polaris®, Roundup Ready® e Roundup WG® com chlorimuron-ethyl (Classic®, e suas associações com óleo mineral (Joint Oil® e inseticidas novaluron (Gallaxy 100 EC®, permethrin (Piredan® e methomyl (Lannate BR®, um experimento foi conduzido a campo na cidade de Maracaí-SP, na safra 2006/2007. O delineamento experimental utilizado foi o de blocos ao acaso, com quatro repetições, em esquema fatorial 16 x 4, sendo 16 as associações das misturas em tanque entre as formulações de glyphosate, óleo mineral e inseticidas e quatro cultivares: Monsoy 7210RR®, Monsoy 7979RR®, BRS 245RR® e CD 214RR®. Sintomas visuais de intoxicação inicial dos cultivares estudados foram caracterizados por clorose e encarquilhamento nas folhas para todas as misturas em tanque das formulações de glyphosate + chlorimuron-ethyl, associadas ou não ao óleo mineral e inseticidas novaluron, permethrin e methomyl. Todas as misturas em tanque não promoveram reduções significativas de produtividade para os cultivares Monsoy 7210RR®, Monsoy 7979RR® e BRS 245RR® e controlaram Ipomoea spp. com eficácia apenas satisfatória a partir dos 21 DAA (dias após aplicação.The use of glyphosate for weed control in soybean RR® presents essential practical characteristics. However, although not allowed by the current Brazilian legislation, the association with other herbicides has been increasing for species of difficult control, as well as the use of tank

  18. Application of multi-criteria material selection techniques to constituent refinement in biobased composites

    International Nuclear Information System (INIS)

    Miller, Sabbie A.; Lepech, Michael D.; Billington, Sarah L.

    2013-01-01

    Highlights: • Biobased composites have the potential to replace certain engineered materials. • Woven reinforcement can provide better material properties in biobased composites. • Short fiber filler can provide lower environmental impact in biobased composites. • Per function, different fibers are desired to lower composite environmental impact. - Abstract: Biobased composites offer a potentially low environmental impact material option for the construction industries. Designing these materials to meet both performance requirements for an application and minimize environmental impacts requires the ability to refine composite constituents based on environmental impact and mechanical properties. In this research, biobased composites with varying natural fiber reinforcement in a poly(β-hydroxybutyrate)-co-(β-hydroxyvalerate) matrix were characterized based on material properties through experiments and environmental impact through life cycle assessments. Using experimental results, these biobased composites were found to have competitive flexural properties and thermal conductivity with certain short-chopped glass fiber reinforced plastics. Multi-criteria material selection techniques were applied to weigh desired material properties with greenhouse gas emissions, fossil fuel demand, and Eco-Indicator ’99 score. The effects of using different reinforcing fibers in biobased composites were analyzed using the developed selection scheme as a tool for choosing constituents. The use of multi-criteria material selection provided the ability to select fiber reinforcement for biobased composites and showed when it would be more appropriate to use a novel biobased composite or a currently available engineered material

  19. Sizing of "Mother Ship and Catcher" Concepts for LEO Small Debris Capture

    Science.gov (United States)

    Bacon, John B.

    2009-01-01

    Most Low Earth Orbit (LEO) debris lies in a limited number of inclination "bands" associated with launch latitudes, or with specific useful orbit inclinations (such as polar orbits). Such narrow inclination bands generally have a uniform spread over all possible Right Ascensions of Ascending Node (RAANs), creating a different orbit plane for nearly every piece of debris. This complicates concept of rendezvous and capture for debris removal. However, a low-orbiting satellite will always phase in RAAN faster than debris objects in higher orbits at the same inclination, potentially solving the problem. Such a base can serve as a single space-based launch facility (a "mother ship") that can tend and then send tiny individual catcher devices for each debris object, as the facility drifts into the same RAAN as the higher object. This presentation will highlight characteristic system requirements of such an architecture, including structural and navigation requirements, power, mass and dV budgets for both the mother ship and the mass-produced common catcher devices that would clean out selected inclination bands. The altitude and inclination regime over which a band is to be cleared, the size distribution of the debris, and the inclusion of additional mission priorities all affect the sizing of the system. It is demonstrated that major LEO hazardous debris reductions can be realized in each band with a single LEO launch of a single mother ship, with simple attached catchers of total mass less than typical commercial LEO launch capability.

  20. Analysis of the effects of simulated synergistic LEO environment on solar panels

    Science.gov (United States)

    Allegri, G.; Corradi, S.; Marchetti, M.; Scaglione, S.

    2007-02-01

    The effects due to the LEO environment exposure of a solar array primary structure are here presented and discussed in detail. The synergistic damaging components featuring LEO environment are high vacuum, thermal cycling, neutral gas, ultraviolet (UV) radiation and cold plasma. The synergistic effects due to these environmental elements are simulated by "on ground" tests, performed in the Space Environment Simulator (SAS) at the University of Rome "La Sapienza"; numerical simulations are performed by the Space Environment Information System (SPENVIS), developed by the European Space Agency (ESA). A "safe life" design for a solar array primary structure is developed, taking into consideration the combined damaging action of the LEO environment components; therefore results from both numerical and experimental simulations are coupled within the framework of a standard finite element method (FEM) based design. The expected durability of the solar array primary structure, made of laminated sandwich composite, is evaluated assuming that the loads exerted on the structure itself are essentially dependent on thermo-elastic stresses. The optical degradation of surface materials and the stiffness and strength degradation of structural elements are taken into account to assess the global structural durability of the solar array under characteristic operative conditions in LEO environment.

  1. Readability in reading materials selection and coursebook design for college English in China

    OpenAIRE

    Lu, Zhongshe

    2002-01-01

    This thesis studies the application of readability in reading materials selection and coursebook design for college English in an EFL context in China. Its aim is to develop rationales which coursebook writers can utilise in selecting materials as texts and as a basis for designing tasks. This study, through a combination of quantitative and qualitative research methods, argues that readability is applicable in the EFL Chinese context, and readability plays a important role in determining...

  2. Leo Satellite Communication through a LEO Constellation using TCP/IP Over ATM

    Science.gov (United States)

    Foore, Lawrence R.; Konangi, Vijay K.; Wallett, Thomas M.

    1999-01-01

    The simulated performance characteristics for communication between a terrestrial client and a Low Earth Orbit (LEO) satellite server are presented. The client and server nodes consist of a Transmission Control Protocol /Internet Protocol (TCP/IP) over ATM configuration. The ATM cells from the client or the server are transmitted to a gateway, packaged with some header information and transferred to a commercial LEO satellite constellation. These cells are then routed through the constellation to a gateway on the globe that allows the client/server communication to take place. Unspecified Bit Rate (UBR) is specified as the quality of service (QoS). Various data rates are considered.

  3. Integrated shape and material selection for single and multi-performance criteria

    International Nuclear Information System (INIS)

    Singh, Jasveer; Mirjalili, Vahid; Pasini, Damiano

    2011-01-01

    Research highlights: → The method of shape transformers is extended to torsional stiffness and combined load design. → The method is generalized for multi-criteria selection of shape and material. → Performance charts are presented for single and multi-objective selection of cross-section shape and material. → A four quadrant performance chart is presented to visualize the relation between objective function space and design variable space. -- Abstract: A shape and material selection method, based on the concept of shape transformers, has been recently introduced to characterize the mass efficiency of lightweight beams under bending and shear. This paper extends this method to deal with the case of torsional stiffness design, and generalize it to single and multi-crieria selection of lightweight shafts subjected to a combination of bending, shear, and torsional load. The novel feature of the paper is the useful integration of shape and material to model and visualize multi-objective selection problems. The scheme is centered on concept selection in structural design, and hinges on measures that govern the shape properties of a cross-section regardless of its size. These measures, referred as shape transformers, can classify shapes in a way similar to material classification. The procedure is exemplified by considering torsional stiffness as a constraint. The performance charts are developed for single and multi-criteria to visualize in a glance the whole range of cross-sectional shapes for each material. Each design chart is explained with a brief example.

  4. Leo Spacecraft Charging Design Guidelines: A Proposed NASA Standard

    Science.gov (United States)

    Hillard, G. B.; Ferguson, D. C.

    2004-01-01

    Over the past decade, Low Earth Orbiting (LEO) spacecraft have gradually required ever-increasing power levels. As a rule, this has been accomplished through the use of high voltage systems. Recent failures and anomalies on such spacecraft have been traced to various design practices and materials choices related to the high voltage solar arrays. NASA Glenn has studied these anomalies including plasma chamber testing on arrays similar to those that experienced difficulties on orbit. Many others in the community have been involved in a comprehensive effort to understand the problems and to develop practices to avoid them. The NASA Space Environments and Effects program, recognizing the timeliness of this effort, commissioned and funded a design guidelines document intended to capture the current state of understanding. This document, which was completed in the spring of 2003, has been submitted as a proposed NASA standard. We present here an overview of this document and discuss the effort to develop it as a NASA standard.

  5. Selecting Materials on the Iranian Revolution: A Short Bibliography of Materials Now in Print.

    Science.gov (United States)

    Sanchez, James Joseph

    Appropriate for adult reading, 27 books published between 1969 and 1982 are listed in this annotated bibliography for those studying the Iranian Revolution. Works are arranged into two categories: (1) "Background Materials: Islam and Petroleum," which lists basic works that make it easier to place events in Iran within an intelligible…

  6. Design and material selection for ITER first wall/blanket, divertor and vacuum vessel

    Energy Technology Data Exchange (ETDEWEB)

    Ioki, K.; Barabash, V.; Cardella, A.; Elio, F.; Gohar, Y.; Janeschitz, G.; Johnson, G.; Kalinin, G.; Lousteau, D.; Onozuka, M.; Parker, R.; Sannazzaro, G.; Tivey, R. [ITER JCT, Garching (Germany)

    1998-10-01

    Design and R and D have progressed on the ITER vacuum vessel, shielding and breeding blankets, and the divertor. The principal materials have been selected and the fabrication methods selected for most of the components based on design and R and D results. The resulting design changes are discussed for each system. (orig.) 11 refs.

  7. Design and material selection for ITER first wall/blanket, divertor and vacuum vessel

    Science.gov (United States)

    Ioki, K.; Barabash, V.; Cardella, A.; Elio, F.; Gohar, Y.; Janeschitz, G.; Johnson, G.; Kalinin, G.; Lousteau, D.; Onozuka, M.; Parker, R.; Sannazzaro, G.; Tivey, R.

    1998-10-01

    Design and R&D have progressed on the ITER vacuum vessel, shielding and breeding blankets, and the divertor. The principal materials have been selected and the fabrication methods selected for most of the components based on design and R&D results. The resulting design changes are discussed for each system.

  8. Zirconium-modified materials for selective adsorption and removal of aqueous arsenic

    Science.gov (United States)

    Zhao, Hongting; Moore, Robert C.

    2004-11-30

    A method, composition, and apparatus for removing contaminant species from an aqueous medium comprising: providing a material to which zirconium has been added, the material selected from one or more of zeolites, cation-exchangeable clay minerals, fly ash, mesostructured materials, activated carbons, cellulose acetate, and like porous and/or fibrous materials; and contacting the aqueous medium with the material to which zirconium has been added. The invention operates on all arsenic species in the form of arsenate, arsenite and organometallic arsenic, with no pretreatment necessary (e.g., oxidative conversion of arsenite to arsenate).

  9. Selected Bibliography of Egyptian Educational Materials, Vol. 1, No. 3, 1975.

    Science.gov (United States)

    Al-Ahram Center for Scientific Translations, Cairo (Egypt).

    There are 101 selected entries in this annotated bibliography of Egyptian materials on education published in 1975. Materials include journal articles, books, and government documents. The bibliography covers the following topics: academic certificates and dissertations, art education, audiovisual aids, camps, civics curricula, conferences and…

  10. Selected Bibliography of Egyptian Educational Materials, Vol. 3, No. 1, 1977.

    Science.gov (United States)

    Al-Ahram Center for Scientific Translations, Cairo (Egypt).

    This annotated bibliography lists 135 selected educational materials from Egypt covering the period 1976-1977. The materials are drawn from a variety of Egyptian newspapers, journals, government publications, and university research reports. The entries are organized into 55 categories, including Adolescence; Adult Education; Art Education; Basic…

  11. Selected Bibliography of Egyptian Educational Materials, Vol. 1, No. 2, 1975.

    Science.gov (United States)

    Al-Ahram Center for Scientific Translations, Cairo (Egypt).

    There are 108 selected entries in this annotated bibliography of Egyptian materials on education published in 1975. Materials include journal articles, books, and government documents. The bibliography covers the following topics: adolescence, art education, child upbringing, comprehensive schools, curricula, educational change, educational aids,…

  12. Selected Bibliography of Egyptian Educational Materials, Vol. 3, No. 2, 1977.

    Science.gov (United States)

    Al-Ahram Center for Scientific Translations, Cairo (Egypt).

    The annotated bibliography identifies 134 selected educational materials from Egypt published during 1977. The materials are drawn from Egyptian newspapers, journals, government publications, and university research reports. The entries are organized into 54 categories, including Art Education, Arabic Language, Commercial Schools, Curricula,…

  13. Materials Down Select Decisions Made Within the Department of Energy Hydrogen Sorption Center of Excellence

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, Lin [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2009-11-30

    Technical report describing DOE's Hydrogen Sorption Center of Excellence investigation into various adsorbent and chemisorption materials and progress towards meeting DOE's hydrogen storage targets. The report presents a review of the material status as related to DOE hydrogen storage targets and explains the basis for the down select decisions.

  14. Assessment of Heat Hazard during the Polymerization of Selected Light-Sensitive Dental Materials

    OpenAIRE

    Janeczek, Maciej; Herman, Katarzyna; Fita, Katarzyna; Dudek, Krzysztof; Kowalczyk-Zaj?c, Ma?gorzata; Czajczy?ska-Waszkiewicz, Agnieszka; Piesiak-Pa?czyszyn, Dagmara; Kosior, Piotr; Dobrzy?ski, Maciej

    2016-01-01

    Introduction. Polymerization of light-cured dental materials used for restoration of hard tooth tissue may lead to an increase in temperature that may have negative consequence for pulp vitality. Aim. The aim of this study was to determine maximum temperatures reached during the polymerization of selected dental materials, as well as the time that is needed for samples of sizes similar to those used in clinical practice to reach these temperatures. Materials and Methods. The study involved fo...

  15. Materials design considerations and selection for a large rad waste incinerator

    International Nuclear Information System (INIS)

    Vormelker, P.R.; Jenkins, C.F.; Burns, H.H.

    1997-01-01

    A new incinerator has been built to process self-generated, low level radioactive wastes at the Department of Energy's Savannah River Site. Wastes include protective clothing and other solid materials used during the handling of radioactive materials, and liquid chemical wastes resulting from chemical and waste management operations. The basic design and materials of construction selected to solve the anticipated corrosion problems from hot acidic gases are reviewed. Problems surfacing during trial runs prior to radioactive operations are discussed

  16. Assessment and selection of materials for ITER in-vessel components

    Science.gov (United States)

    Kalinin, G.; Barabash, V.; Cardella, A.; Dietz, J.; Ioki, K.; Matera, R.; Santoro, R. T.; Tivey, R.; ITER Home Teams

    2000-12-01

    During the international thermonuclear experimental reactor (ITER) engineering design activities (EDA) significant progress has been made in the selection of materials for the in-vessel components of the reactor. This progress is a result of the worldwide collaboration of material scientists and industries which focused their effort on the optimisation of material and component manufacturing and on the investigation of the most critical material properties. Austenitic stainless steels 316L(N)-IG and 316L, nickel-based alloys Inconel 718 and Inconel 625, Ti-6Al-4V alloy and two copper alloys, CuCrZr-IG and CuAl25-IG, have been proposed as reference structural materials, and ferritic steel 430, and austenitic steel 304B7 with the addition of boron have been selected for some specific parts of the ITER in-vessel components. Beryllium, tungsten and carbon fibre composites are considered as plasma facing armour materials. The data base on the properties of all these materials is critically assessed and briefly reviewed in this paper together with the justification of the material selection (e.g., effect of neutron irradiation on the mechanical properties of materials, effect of manufacturing cycle, etc.).

  17. Controlling the Growth of Future LEO Debris Populations with Active Debris Removal

    Science.gov (United States)

    Liou, J.-C.; Johnson, N. L.; Hill, N. M.

    2008-01-01

    Active debris removal (ADR) was suggested as a potential means to remediate the low Earth orbit (LEO) debris environment as early as the 1980s. The reasons ADR has not become practical are due to its technical difficulties and the high cost associated with the approach. However, as the LEO debris populations continue to increase, ADR may be the only option to preserve the near-Earth environment for future generations. An initial study was completed in 2007 to demonstrate that a simple ADR target selection criterion could be developed to reduce the future debris population growth. The present paper summarizes a comprehensive study based on more realistic simulation scenarios, including fragments generated from the 2007 Fengyun-1C event, mitigation measures, and other target selection options. The simulations were based on the NASA long-term orbital debris projection model, LEGEND. A scenario, where at the end of mission lifetimes, spacecraft and upper stages were moved to 25-year decay orbits, was adopted as the baseline environment for comparison. Different annual removal rates and different ADR target selection criteria were tested, and the resulting 200-year future environment projections were compared with the baseline scenario. Results of this parametric study indicate that (1) an effective removal strategy can be developed based on the mass and collision probability of each object as the selection criterion, and (2) the LEO environment can be stabilized in the next 200 years with an ADR removal rate of five objects per year.

  18. Assessment and Selection of Materials for Melbourne City Council House 2

    Directory of Open Access Journals (Sweden)

    Dominique Hes

    2012-11-01

    Full Text Available This paper highlights the role of material selection in the development and contribution toward environmental excellence in the building project Council House 2 (CH2. The paper focuses on the assessment of material and the strategies used by the design team in CH2to ensure the best environmental result. The paper then goes on to explore in a case study the application of these strategies in the selection and specification of concrete on CH2. The purpose of the paper is to explore the difficulties and rewards of careful research of manufacturers' claims and the relative benefits of different materials. The paper concludes that the process of material selection adopted on this project has increased the education of architects and manufacturers alike as well as being environmentally beneficial.

  19. Multicriteria Decision Analysis of Material Selection of High Energy Performance Residential Building

    Science.gov (United States)

    Čuláková, Monika; Vilčeková, Silvia; Katunská, Jana; Krídlová Burdová, Eva

    2013-11-01

    In world with limited amount of energy sources and with serious environmental pollution, interest in comparing the environmental embodied impacts of buildings using different structure systems and alternative building materials will be increased. This paper shows the significance of life cycle energy and carbon perspective and the material selection in reducing energy consumption and emissions production in the built environment. The study evaluates embodied environmental impacts of nearly zero energy residential structures. The environmental assessment uses framework of LCA within boundary: cradle to gate. Designed alternative scenarios of material compositions are also assessed in terms of energy effectiveness through selected thermal-physical parameters. This study uses multi-criteria decision analysis for making clearer selection between alternative scenarios. The results of MCDA show that alternative E from materials on nature plant base (wood, straw bales, massive wood panel) present possible way to sustainable perspective of nearly zero energy houses in Slovak republic

  20. Decision method for optimal selection of warehouse material handling strategies by production companies

    Science.gov (United States)

    Dobos, P.; Tamás, P.; Illés, B.

    2016-11-01

    Adequate establishment and operation of warehouse logistics determines the companies’ competitiveness significantly because it effects greatly the quality and the selling price of the goods that the production companies produce. In order to implement and manage an adequate warehouse system, adequate warehouse position, stock management model, warehouse technology, motivated work force committed to process improvement and material handling strategy are necessary. In practical life, companies have paid small attantion to select the warehouse strategy properly. Although it has a major influence on the production in the case of material warehouse and on smooth costumer service in the case of finished goods warehouse because this can happen with a huge loss in material handling. Due to the dynamically changing production structure, frequent reorganization of warehouse activities is needed, on what the majority of the companies react basically with no reactions. This work presents a simulation test system frames for eligible warehouse material handling strategy selection and also the decision method for selection.

  1. Facile Selective and Diverse Fabrication of Superhydrophobic, Superoleophobic-Superhydrophilic and Superamphiphobic Materials from Kaolin.

    Science.gov (United States)

    Qu, Mengnan; Ma, Xuerui; He, Jinmei; Feng, Juan; Liu, Shanshan; Yao, Yali; Hou, Lingang; Liu, Xiangrong

    2017-01-11

    As the starting material, kaolin is selectively and diversely fabricated to the superhydrophobic, superoleophobic-superhydrophilic, and superamphiphobic materials, respectively. The wettability of the kaolin surface can be selectively controlled and regulated to different superwetting states by choosing the corresponding modification reagent. The procedure is facile to operate, and no special technique or equipment is required. In addition, the procedure is cost-effective and time-saving and the obtained super-repellent properties are very stable. The X-ray photoelectron spectroscopy analysis demonstrates different changes of kaolin particles surfaces which are responsible for the different super-repellency. The scanning electron microscopy displays geometric micro- and nanometer structures of the obtained three kinds of super-repellent materials. The results show that kaolin has good applications in many kinds of superwetting materials. The method demonstrated in this paper provides a new strategy for regulating and controlling the wettability of solid surfaces selectively, diversely, and comprehensively.

  2. Leo Kunnas : triibuline särk kuuli ei peata / Leo Kunnas ; interv. Jaanus Piirsalu

    Index Scriptorium Estoniae

    Kunnas, Leo, 1967-

    2006-01-01

    2005. aastal koalitsioonijõudude koosseisus Iraagis teeninud Leo Kunnas selgitab intervjuus, mida on Eesti kaitsevägi Iraagi missioonist õppinud, millist mõju on Eesti sõdurite osalemine välismissioonides avaldanud ühiskonnale, lisaks võrdleb Iraagi ja Afganistani missioone ning põhjendab, miks on palgaarmee loomise idee Eestis sõjaliselt mitterelevantne

  3. Selection of IFE target materials from a safety and environmental perspective

    Energy Technology Data Exchange (ETDEWEB)

    Latkowski, J.F. E-mail: latkowski1@llnl.gov; Sanz, J.; Reyes, S.; Gomez del Rio, J

    2001-05-21

    Target materials for inertial fusion energy (IFE) power plant designs might be selected for a wide variety of reasons including wall absorption of driver energy, material opacity, cost and ease of fabrication. While each of these issues are of great importance, target materials should also be selected based upon their safety and environmental (S and E) characteristics. The present work focuses on the recycling, waste management and accident dose characteristics of potential target materials. If target materials are recycled so that the quantity is small, isotopic separation may be economically viable. Therefore, calculations have been completed for all stable isotopes for all elements from lithium to polonium. The results of these calculations are used to identify specific isotopes and elements that are most likely to be offensive as well as those most likely to be acceptable in terms of their S and E characteristics.

  4. Selection of IFE target materials from a safety and environmental perspective

    Science.gov (United States)

    Latkowski, J. F.; Sanz, J.; Reyes, S.; Gomez del Rio, J.

    2001-05-01

    Target materials for inertial fusion energy (IFE) power plant designs might be selected for a wide variety of reasons including wall absorption of driver energy, material opacity, cost and ease of fabrication. While each of these issues are of great importance, target materials should also be selected based upon their safety and environmental (S&E) characteristics. The present work focuses on the recycling, waste management and accident dose characteristics of potential target materials. If target materials are recycled so that the quantity is small, isotopic separation may be economically viable. Therefore, calculations have been completed for all stable isotopes for all elements from lithium to polonium. The results of these calculations are used to identify specific isotopes and elements that are most likely to be offensive as well as those most likely to be acceptable in terms of their S&E characteristics.

  5. Materials selection for process equipment in the Hanford waste vitrification plant

    Energy Technology Data Exchange (ETDEWEB)

    Elmore, M R; Jensen, G A

    1991-07-01

    The Hanford Waste Vitrification Plant (HWVP) is being designed to vitrify defense liquid high-level wastes and transuranic wastes stored at Hanford. The HWVP Functional Design Criteria (FDC) requires that materials used for fabrication of remote process equipment and piping in the facility be compatible with the expected waste stream compositions and process conditions. To satisfy FDC requirements, corrosion-resistant materials have been evaluated under simulated HWVP-specific conditions and recommendations have been made for HWVP applications. The materials recommendations provide to the project architect/engineer the best available corrosion rate information for the materials under the expected HWVP process conditions. Existing data and sound engineering judgement must be used and a solid technical basis must be developed to define an approach to selecting suitable construction materials for the HWVP. This report contains the strategy, approach, criteria, and technical basis developed for selecting materials of construction. Based on materials testing specific to HWVP and on related outside testing, this report recommends for constructing specific process equipment and identifies future testing needs to complete verification of the performance of the selected materials. 30 refs., 7 figs., 11 tabs.

  6. Tokamak Physics EXperiment (TPX): Toroidal field magnet design, development and manufacture. SDRL 21, Materials and processes selection. Volume 2

    International Nuclear Information System (INIS)

    Smith, B.R.

    1995-01-01

    This document identifies the candidate materials and manufacturing processes selected for development of the TPX Toroidal Field (TF) Magnet. Supporting rationale and selection criteria are provided for justification and the materials properties database report is included for completeness. Specific properties for each material selection are included in this document

  7. Tempo de destilação e perfil volátil do óleo essencial de aroeira da praia (Schinus terebinthifolius em Sergipe

    Directory of Open Access Journals (Sweden)

    L.F.M. Oliveira

    2014-06-01

    Full Text Available Aos frutos e óleos essenciais da aroeira da praia (Schinus terebinthifolius atribui-se atividade antimicrobiana sobre bactérias gram positivas além de ação anti-inflamatória. O óleo essencial da aroeira é utilizado no tratamento de micoses, sendo a sua atividade antifúngica atribuída à alta concentração de monoterpenos. Este estudo teve como objetivo determinar o melhor rendimento de destilação de óleo essencial de sementes e folhas da aroeira e os componentes químicos do óleo essencial nos diversos períodos de destilação. Cem gramas de cada material foram destilados em aparato de Clevenger durante 2,5h, 4,0h, 5,5h e 7,0h. O material destilado foi analisado por cromatografia a gás acoplada a espectrofotômetro de massas, onde foi obtido o perfil cromatográfico do material. As sementes de aroeira apresentaram maiores quantidades de óleo essencial, quando comparadas com as folhas em todos os períodos de destilação. O óleo essencial de aroeira mostrou perfil volátil formado principalmente por mono e sesquiterpenos.

  8. The Leo I color-magnitude diagram

    International Nuclear Information System (INIS)

    Reid, N.; Mould, J.

    1991-01-01

    The R-and I-band photometry of the Leo I dwarf galaxy is presented. A relatively narrow giant branch is found, Implying an abundance range of no more than Fe/H/= - 0.7 to - 1.3. This is in contrast to the results is found by Fox and Pritchet (1987) from BV CCD photometry. The distance modulus is estimated as (m - M) = 21.85 + or - 0.15, based on the luminosity of the tip of the red giant branch. 15 refs

  9. El fin del petróleo

    OpenAIRE

    Fontaine, Guillaume

    2007-01-01

    En el momento en que los demócratas de los Estados Unidos han encabezado, al parecer, la cruzada mundial contra el cambio climático, quizá no es inútil leer (o releer) el ensayo del periodista Paul Roberts, publicado a finales del 2004 bajo el título llamativo de "El fin del petróleo". En efecto, cuando se reactivan las recetas del "charity business" (como eran los megaconciertos contra la hambruna y la sequía en Somalia, o para la liberación de Mandela) para salvar nuestro planeta, y m...

  10. Louis Althusser, Leo Strauss, and Democratic Leadership

    OpenAIRE

    Tamulis, Bron Cohen

    2014-01-01

    In taking up the topic of political leadership, I seek to analyze the legacy of social science in light of the sobering political events of the twentieth century. This dissertation is a composite study of the work of two philosophers, and, specifically, what they endeavored to accomplish by thinking and writing on the subject of politics. I concentrated on the post-War landscape, and the philosophers Louis Althusser and Leo Strauss, in order to analyze the way in which the figure of Machiav...

  11. Bioactive treatment promotes osteoblast differentiation on titanium materials fabricated by selective laser melting technology.

    Science.gov (United States)

    Tsukanaka, Masako; Fujibayashi, Shunsuke; Takemoto, Mitsuru; Matsushita, Tomiharu; Kokubo, Tadashi; Nakamura, Takashi; Sasaki, Kiyoyuki; Matsuda, Shuichi

    2016-01-01

    Selective laser melting (SLM) technology is useful for the fabrication of porous titanium implants with complex shapes and structures. The materials fabricated by SLM characteristically have a very rough surface (average surface roughness, Ra=24.58 µm). In this study, we evaluated morphologically and biochemically the specific effects of this very rough surface and the additional effects of a bioactive treatment on osteoblast proliferation and differentiation. Flat-rolled titanium materials (Ra=1.02 µm) were used as the controls. On the treated materials fabricated by SLM, we observed enhanced osteoblast differentiation compared with the flat-rolled materials and the untreated materials fabricated by SLM. No significant differences were observed between the flat-rolled materials and the untreated materials fabricated by SLM in their effects on osteoblast differentiation. We concluded that the very rough surface fabricated by SLM had to undergo a bioactive treatment to obtain a positive effect on osteoblast differentiation.

  12. Development of a material property database on selected ceramic matrix composite materials

    Science.gov (United States)

    Mahanta, Kamala

    1996-01-01

    Ceramic Matrix Composites, with fiber/whisker/particulate reinforcement, possess the attractive properties of ceramics such as high melting temperature, high strength and stiffness at high temperature, low density, excellent environmental resistance, combined with improved toughness and mechanical reliability. These unique properties have made these composites an enabling technology for thermomechanically demanding applications in high temperature, high stress and aggressive environments. On a broader scale, CMC's are anticipated to be applicable in aircraft propulsion, space propulsion, power and structures, in addition to ground based applications. However, it is also true that for any serious commitment of the material toward any of the intended critical thermo-mechanical applications to materialize, vigorous research has to be conducted for a thorough understanding of the mechanical and thermal behavior of CMC's. The high technology of CMC'S is far from being mature. In view of this growing need for CMC data, researchers all over the world have found themselves drawn into the characterization of CMC's such as C/SiC, SiC/SiC, SiC/Al203, SiC/Glass, SiC/C, SiC/Blackglas. A significant amount of data has been generated by the industries, national laboratories and educational institutions in the United States of America. NASA/Marshall Space Flight Center intends to collect the 'pedigreed' CMC data and store those in a CMC database within MAPTIS (Materials and Processes Technical Information System). The task of compilation of the CMC database is a monumental one and requires efforts in various directions. The project started in the form of a summer faculty fellowship in 1994 and has spilled into the months that followed and into the summer faculty fellowship of 1995 and has the prospect of continuing into the future for a healthy growth, which of course depends to a large extent on how fast CMC data are generated. The 10-week long summer fellowship has concentrated

  13. Selection of construction materials for equipment in an experimental reprocessing plant

    International Nuclear Information System (INIS)

    Mizrahi, R.; Cragnolino, G.A.

    1994-01-01

    A review is made of the most significant corrosion problems that may be present in different stages of the process in a spent fuel reprocessing plant. The influence of different variables is analyzed: concentration of nitric acid and other oxidizing species, temperature, etc., in corrosion of materials of most frequent use in pipings and equipment. The materials are austenitic stainless steels and refractory metals, especially zirconium and its alloys. Both general and localized corrosion phenomena are analyzed for these materials. Selection criteria for the use of adequate material in different components of the plant are also discussed. (author). 32 refs., 20 figs., 3 tabs

  14. Viiv enne kojuminekut / Leo Kunnas ; interv. Helen Arak

    Index Scriptorium Estoniae

    Kunnas, Leo, 1967-

    2006-01-01

    Kaitsejõudude Peastaabi operatiivosakonna ülem kolonelleitnant Leo Kunnas oma perekonnast, lapsepõlvekodust Põlvamaal ja praegusest elamisest Tallinnas, missioonil viibivate sõjaväelaste probleemidest ning eluolust Iraagis. Lisa: Katkend Leo Kunnase raamatust "Viiv pikas sõjas"

  15. Introducing Leo LT - the "three-headed lion"

    Index Scriptorium Estoniae

    2008-01-01

    Leedu valitsus kiitis heaks seaduseparandused, mille tulemusena saab võtta tuumajaama ehitaja, investeerimis- ja energiafirma Leo LT strateegilise tähtsusega firmade hulka. Kui parlament valitsuse ettepanekud heaks kiidab, saab riik 61,7% Leo LT ja 38,3% NDX Energija aktsiatest

  16. Possibilidade de seleção recorrente para aumento do teor de óleo em soja com a utilização da macho-esterilidade genética e da espectroscopia de ressonância nuclear magnética The possibility of recurrent selection to increase the oil content in soybeans using genetic male sterility and NMR spectroscopy

    Directory of Open Access Journals (Sweden)

    Manoel Albino Coelho de Miranda

    1989-01-01

    Full Text Available Com a finalidade de estudar a possibilidade de realizar seleção recorrente, analisaram-se sementes de soja de plantas macho-estéreis e de sua progênies quanto ao teor de óleo no espectroscópio de ressonância nuclear magnética (NMR, no Instituto de Física da Universidade de Campinas de 1984 a 1988. Tais sementes provinham do composto IAC-1, com macho-esterilidade genética e ampla variabilidade quanto à percentagem de óleo (13,5-22,5%. Determinaram-se os coeficientes de repetibilidade, tomando-se o teor de óleo de cada semente da planta macho-estéril como uma medida fenotípica, obtendo-se o valor médio de r = 0,65. Concluiu-se que com a análise de quatro a cinco sementes, é possível representar a planta-mãe, passo importante para viabilizar a seleção recorrente nessa população, visto o pequeno número de sementes produzidas por planta macho-estéril. Utilizando-se a covariância entre a média das sementes da planta macho-estéril e a média de suas progênies, obteve-se h² = 0,73. Essa herdabilidade é alta, e como o caráter teor de óleo tem como principal componente de sua variância genética a variância aditiva, pode-se recomendar a seleção fenotípica. Calculou-se também o coeficiente de herdabilidade no nível da média de progênies, obtendo-se valores desde 0,66, para a média de duas plantas por progênie, até 0,85, para a de sete plantas por progênie. Esses resultados demonstram a possibilidade de seleção recorrente no composto IAC-1, tanto no campo, ao nível de planta macho-estéril, como em casa de vegetação, em seleção baseada na média da progênie.The seed oil content of male sterile plants and their progenies was analised by a NMR spectroscope to study the possibility of recurrent selection to improve the oil content. The seeds derived from a composite named "IAC-1" with genetic male sterility and large variability with respect to oil content. The repeatability coefficient (r for oil content

  17. Selection of engineering materials for heat exchangers (An expert system approach)

    International Nuclear Information System (INIS)

    Ahmed, K.; Abou-Ali, M.; Bassuni, M.

    1997-01-01

    The materials selection as a part of the design process of the heat exchangers is one of the most important steps in the whole industry. The clear recognition of the service requirements of the different types of the heat exchangers is very important to select the adequate and economic materials to meet such requirements. of course the manufacturer should ensure that failure does not occur in service specially it is one of the main and fetal component of the nuclear reactor, pressurized water type (PWR). It is necessary to know the possible mechanisms of failure. Also the achievement of the materials selection using the expert system approach in the process sequence of heat exchanger manufacturing is introduced. Different parameters and requirements controlling each process and the linkage between these parameters and the final product will be shown. 2 figs., 3 tabs

  18. Selection of replacement material for the failed surface level gauge wire in Hanford waste tanks

    International Nuclear Information System (INIS)

    Anantatmula, R.P.; Pitman, S.G.; Lund, A.L.

    1995-10-01

    Surface level gauges fabricated from AISI Type 316 stainless steel (316) wire failed after only a few weeks of operation in underground storage tanks at the Hanford Site. The wire failure was determined to be due to chloride ion assisted corrosion of the 316 wire. Radiation-induced breakdown of the polyvinyl chloride (PVC) riser liners is suspected to be the primary source of the chloride ions. An extensive literature search followed by expert concurrence was undertaken to select a replacement material for the wire. Platinum (Pt)-20 % Iridium (Ir) alloy was selected as the replacement material from tile candidate materials, P-20% Ir, Pt-1O% Rhodium (Rh), Pt-20%Rh and Hastelloy C-22. The selection was made on the basis of the alloy's immunity towards acidic and basic environments as well as its adequate tensile properties in the fully annealed state

  19. Selection criteria for container materials at the proposed Yucca Mountain high level nuclear waste repository

    International Nuclear Information System (INIS)

    Halsey, W.G.

    1989-11-01

    A geological repository has been proposed for the permanent disposal of the nation's high level nuclear waste at Yucca Mountain in the Nevada desert. The containers for this waste must remain intact for the unprecedented service lifetime of 1000 years. A combination of engineering, regulatory, and licensing requirements complicate the container material selection. In parallel to gathering information regarding the Yucca Mountain service environment and material performance data, a set of selection criteria have been established which compare candidate materials to the performance requirements, and allow a quantitative comparison of candidates. These criteria assign relative weighting to varied topic areas such as mechanical properties, corrosion resistance, fabricability, and cost. Considering the long service life of the waste containers, it is not surprising that the corrosion behavior of the material is a dominant factor. 7 refs

  20. Selection of emitter material for application on a radioisotope thermophotovoltaic (RTPV) power system

    Energy Technology Data Exchange (ETDEWEB)

    Kramer, D.P.; Frohlich, N.D.; Koehler, F.A.; Ruhkamp, J.D.; Miller, R.G.; McDougal, J.R.; Pugh, B.K.; Barklay, C.D.; Howell, E.I. [EGG Mound Applied Technologies Building 88, P.O. Box 3000 Miamisburg, Ohio45343 (United States)

    1997-01-01

    Radioisotope Thermophotovoltaic (RTPV) power systems are being considered for long duration space missions due to their predicted high thermal to electrical conversion efficiencies. One critical aspect of these power systems is the selection of an appropriate emitter material which will efficiently radiate the thermal energy generated by the heat source to the photovoltaics. The photovoltaics are {open_quotes}tuned{close_quotes} to convert the infrared wavelengths radiated by the emitter into electrical energy. The emphasis of this paper is on the selection and optimization of an appropriate emitter material which would meet all of the mission requirements. A Kepner Tregoe analysis was performed in order to rank the various candidate refractory materials in relationship to their physical and chemical properties. The results of the analysis and material recommendations are discussed. {copyright} {ital 1997 American Institute of Physics.}

  1. Material Selection for Dye Sensitized Solar Cells Using Multiple Attribute Decision Making Approach

    Directory of Open Access Journals (Sweden)

    Sarita Baghel

    2014-01-01

    Full Text Available Dye sensitized solar cells (DSCs provide a potential alternative to conventional p-n junction photovoltaic devices. The semiconductor thin film plays a crucial role in the working of DSC. This paper aims at formulating a process for the selection of optimum semiconductor material for nanostructured thin film using multiple attribute decision making (MADM approach. Various possible available semiconducting materials and their properties like band gap, cost, mobility, rate of electron injection, and static dielectric constant are considered and MADM technique is applied to select the best suited material. It was found that, out of all possible candidates, titanium dioxide (TiO2 is the best semiconductor material for application in DSC. It was observed that the proposed results are in good agreement with the experimental findings.

  2. Omni-directional selective shielding material based on amorphous glass coated microwires.

    Science.gov (United States)

    Ababei, G; Chiriac, H; David, V; Dafinescu, V; Nica, I

    2012-01-01

    The shielding effectiveness of the omni-directional selective shielding material based on CoFe-glass coated amorphous wires in 0.8 GHz-3 GHz microwave frequency range is investigated. The measurements were done in a controlled medium using a TEM cell and in the free space using horn antennas, respectively. Experimental results indicate that the composite shielding material can be developed with desired shielding effectiveness and selective absorption of the microwave frequency range by controlling the number of the layers and the length of microwires.

  3. Materials Selection And Fabrication Practices For Food Processing Equipment Manufacturers In Uganda

    Directory of Open Access Journals (Sweden)

    John Baptist Kirabira

    2017-08-01

    Full Text Available The food processing industry is one of the fast-growing sub-sectors in Uganda. The industry which is majorly composed of medium and small scale firms depends on the locally developed food processing equipment. Due to lack of effective materials selection practices employed by the equipment manufacturers the materials normally selected for most designs are not the most appropriate ones hence compromising the quality of the equipment produced. This has not only led to poor quality food products due to contamination but could also turn out health hazardous to the consumers of the food products. This study involved the assessment of the current materials selection and fabrication procedures used by the food processing equipment manufacturers with a view of devising best practices that can be used to improve the quality of the food products processed by the locally fabricated equipment. Results of the study show that designers experience biasness and desire to minimize cost compromise the materials selection procedure. In addition to failing to choose the best material for a given application most equipment manufacturers are commonly fabricating equipment with inadequate surface finish and improper weldments. This hinders the equipments ability to meet food hygiene standards.

  4. Material Selection for Competition–A Case Study for Air Coolers

    Directory of Open Access Journals (Sweden)

    Luma A. H. Al Kindi

    2018-02-01

    Full Text Available Competition is one of the most important challenges that is facing the marketing of industrial products in today's markets. In this research study of the impact of material selection factor for air coolers of different materials is applied. Investigation on the air cooler windows which are part of the body of air coolers is conducted. Corrosion resistance, thermal conductivity, strength of material, weight, shape, cost and manufacturing process are the factors that are applied and calculated on three types of materials Aluminum, Galvanized steel and polypropylene. The physical properties of the three mentioned materials are used to calculate Merit Index .The corrosion average, according to Tafel Method depending the corrosion current and adopting contactors for the anodic and cathodic metals behaviors is performed. ANSYS is adopted using the three samples for the selected materials Aluminum, Galvanized steel and polypropylene to measure maximum stress and deflection are measured. Accordingly, the results are compared to choose the best alternative. It is observed that the polypropylene is the best choice depending three factors while the aluminum material is better depending two factors and the galvanized steel is regarded as the best in only one factor, the rest factors are identical when choosing  an alternative material for manufacturing the air cooler windows.

  5. AN ASSESSMENT OF FACTORS AFFECTING MATERIAL STOCK CONTROL PRACTICE ON SELECTED CONSTRUCTION SITES IN NIGERIA

    OpenAIRE

    Adafin, Johnson Kayode; Ayodele, Elijah Olusegun; Daramola, Olufemi

    2011-01-01

    This research examines the stock control methods utilized by construction firms on construction sites with a view to assessing the factors affecting material stock control practice by construction firms as well as determining the impact of factors affecting material stock control on building project performance. Data were collected with the aid of well-structured questionnaire administered on a number of construction professionals and technicians in some randomly selected building constructio...

  6. Aspects for selection of materials and fabrication processes for nuclear component manufacturing

    International Nuclear Information System (INIS)

    Pernstich, K.

    1980-01-01

    For components of the Nuclear steam supply System of Light Water Reactors an extremely high safety standard is required. These requirements only can be met by adequate selection of materials and fabrication processes and their proper application in combination with strict quality assurance and control measurements. A general overview of the basic aspects to be considered in this connection is presented together with an indication of the present state of art for the main materials and fabrication processes. (author) [pt

  7. 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

  8. The use of selective electrodes for the control of nuclear materials

    International Nuclear Information System (INIS)

    Pires, M.A.F.; Abrao, A.

    1984-01-01

    The use of ion selective electrodes is discussed for the determination of nitrate, chloride and fluoride in several materials used in the fuel cycle. The determination of nitrate and chloride in thorium compounds, the analysis of fluoride and chloride in uranium compounds and the determination of fluoride in crude phosphoric acid are described. The control of fluoride in urine of individuals that handle materials containing fluor and its compounds is also described. (C.L.B.) [pt

  9. Multiple criteria decision making with life cycle assessment for material selection of composites

    Directory of Open Access Journals (Sweden)

    A. S. Milani

    2011-12-01

    Full Text Available With the advancement of interdisciplinary approaches in today’s modern engineering, current efforts in optimal design of composites include seeking material selection protocols that can (1 simultaneously consider a series of mechanical/electrical/chemical cost criteria over a set of alternative material options, and (2 closely take into account environmental aspects of final products including recycling and end-of-life disposal options. In this paper, in addition to a review of some recent experimental and methodological advances in the above areas, a new application of multiple criteria decision making (MCDM is presented to deal with decision conflicts often seen among design criteria in composite material selection with the help of life cycle assessment (LCA. To show the application, an illustrative case study on a plastic gear material selection is conducted where the cost, mechanical and thermal properties along with environmental impact criteria are to be satisfied simultaneously. A pure plastic gear is compared to a Polyethylene terephthalate (PET/aluminum-powder composite alternative. Results suggest that simple MCDM models, including a signal-to-noise measure adapted to MCDM in the same case study, can be used to explore both trade-offs and design break-even points in large decision spaces as the decision maker’s perspective over environmental, material performance and cost attributes change during the design process. More advanced topics including the account of material data uncertainties are addressed.

  10. Doublet III limiter performance and implications for mechanical design and material selection for future limiters

    International Nuclear Information System (INIS)

    Sabado, M.M.; Marcus, F.B.; Trester, P.W.; Wesley, J.C.

    1979-10-01

    The plasma limiter system for Doublet III is described. Initially, high-Z materials, Ta-10W for the primary limiter and Mo for the backup limiters, were selected as the most attractive metallic candidates from the standpoint of thermal and structural properties. For the purpose of evaluating the effect of material Z on plasma performance, the nonmagnetic, Ni-base alloy Inconel X-750 was selected for a medium-Z limiter material. Graphite, a low-Z material, will likely be the next limiter material for evaluation. Design and material selection criteria for the different Z ranges are presented. The performance of the high-Z limiters in Doublet III is reviewed for an operation period that included approximately 5000 plasma shots. Changes in surface appearance and metallurgical changes are characterized. Discussion is presented on how and to what extent the high-Z elements affected the performance of the plasma based on theory and measurements in Doublet III. The fabrication processes for the Inconel X-750 limiters are summarized, and, last, observations on early performance of the Inconel limiters are described

  11. Doublet III limiter performance and implications for mechanical design and material selection for future limiters

    Energy Technology Data Exchange (ETDEWEB)

    Sabado, M.M.; Marcus, F.B.; Trester, P.W.; Wesley, J.C.

    1979-10-01

    The plasma limiter system for Doublet III is described. Initially, high-Z materials, Ta-10W for the primary limiter and Mo for the backup limiters, were selected as the most attractive metallic candidates from the standpoint of thermal and structural properties. For the purpose of evaluating the effect of material Z on plasma performance, the nonmagnetic, Ni-base alloy Inconel X-750 was selected for a medium-Z limiter material. Graphite, a low-Z material, will likely be the next limiter material for evaluation. Design and material selection criteria for the different Z ranges are presented. The performance of the high-Z limiters in Doublet III is reviewed for an operation period that included approximately 5000 plasma shots. Changes in surface appearance and metallurgical changes are characterized. Discussion is presented on how and to what extent the high-Z elements affected the performance of the plasma based on theory and measurements in Doublet III. The fabrication processes for the Inconel X-750 limiters are summarized, and, last, observations on early performance of the Inconel limiters are described. (MOW)

  12. An integrated approach to selecting materials for fuel cladding in advanced high-temperature reactors

    Energy Technology Data Exchange (ETDEWEB)

    Rangacharyulu, C., E-mail: chary.r@usask.ca [Univ. of Saskatchewan, Saskatoon, SK (Canada); Guzonas, D.A.; Pencer, J.; Nava-Dominguez, A.; Leung, L.K.H. [Atomic Energy of Canada Limited, Chalk River, ON (Canada)

    2014-07-01

    An integrated approach has been developed for selection of fuel cladding materials for advanced high-temperature reactors. Reactor physics, thermalhydraulic and material analyses are being integrated in a systematic study comparing various candidate fuel-cladding alloys. The analyses established the axial and radial neutron fluxes, power distributions, axial and radial temperature distributions, rates of defect formation and helium production using AECL analytical toolsets and experimentally measured corrosion rates to optimize the material composition for fuel cladding. The project has just been initiated at University of Saskatchewan. Some preliminary results of the analyses are presented together with the path forward for the project. (author)

  13. LEO 1.0. An assistant software for maintenance of corroded reinforced concrete structures

    International Nuclear Information System (INIS)

    Gerard, B.; Petre-Lazar, I.

    1998-04-01

    The reinforced concrete structures capacity to fulfill the users requirements decreases in time and a constant preoccupation for the maintenance is required at EDF. In order to ease up the site investigations, a computer program - LEO - is developed. Its general layout is proposed in this document. LEO 1.0 is developed to be applied to corroded reinforced concrete structures. A simplified model based on the main mechanisms of the steel corrosion in concrete has been developed. It can quantify the influence of the reinforcement corrosion on the structure performances. A probabilistic calculus which takes into account the variability of the input data (material properties, environment, etc.) was also performed using PROBAN computer code. This type of analysis quantifies the time evolution of the structure (incubation, initiation, propagation, collapse). (author)

  14. What's Your Money Worth? Materials Budgets and the Selection and Evaluation of Book and Serial Vendors.

    Science.gov (United States)

    Barker, Joseph W.

    1992-01-01

    Discusses budgets for library materials and how to select and evaluate book and serial vendors. Trends in automation, publishing, and economics that affect both libraries and vendors are discussed; and examples from the University of California at Berkeley that include serials service charges and approval plan discounts are presented. (six…

  15. Listening Diary in the Digital Age: Students' Material Selection, Listening Problems, and Perceived Usefulness

    Science.gov (United States)

    Chen, Cheryl Wei-yu

    2016-01-01

    The current study reports on a group of Taiwanese college students' first-person diary accounts of their private, transactional listening activities outside the classroom. Issues related to students' material selection, listening problems, and perceived usefulness of keeping a listening diary were explored. It was found that most students chose…

  16. Information resources and material selection in bonded restorations among Korean dentists.

    Science.gov (United States)

    Chang, Juhea; Kim, Hae-Young; Cho, Byeong Hoon; Lee, In Bog; Son, Ho Hyun

    2009-12-01

    To elucidate how dentists access knowledge sources when choosing adhesive agents for bonded restoration and whether these resources influenced the selection of materials. A national survey was carried out involving dentists in South Korea. The questionnaire included the status of the operator, clinical techniques, and materials. A total of 12,193 e-mails were distributed, 2632 were opened by recipients, and 840 responses were collected. For primary information resources in material selection, 55.8% (n = 469) of the responders mentioned continuing education. This selection criteria varied according to the working status of the clinician (p choice of bonding system was influenced by of the length of the career (p < 0.0001), and the preferred bonding systems differed according to the source of the information (p = 0.035). The popular bonding systems were not ranked according to the bonding strategy, but a preference was found for specific brands or manufacturers. To decrease the confusion of clinicians related to the selection of bonding materials, evidence-based guidelines need to be comprehensibly organized and efficiently approached in clinics.

  17. Leo Kunnas, sõdurjumala teener / Leo Kunnas ; interv. Eve Jaakson

    Index Scriptorium Estoniae

    Kunnas, Leo, 1967-

    2006-01-01

    Kaitsejõudude peastaabi operatiivosakonna ülem kolonelleitnant Leo Kunnas räägib Iraagi sõja kogemustest ja oma raamatust "Viiv pikas sõjas. Märkmeid Iraagi sõjast", riigikaitsest, kaitseväeteenistusest, kaitseminister Jürgen Ligist, kaitsepoliitikast, NATO-st, sõjalisest koostööst, perekonnast. Kommenteerivad Sten Reimann ja Venno Loosaar

  18. Assessment of materials selection and performance for direct-coal- liquefaction plants in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, A.R.; Judkins, R.R.; Keiser, J.R.

    1996-09-01

    Several direct coal liquefaction processes have been demonstrated at the pilot plant level in the United States. Presently only one plant remains operational, namely, the Hydrocarbon Technologies, Inc., 4.0- ton-per-day process development unit in Lawrenceville, New Jersey. The period from 1974 to 1982 saw the greatest amount of development of direct coal liquefaction in the United States with four major pilot plants being devoted to variants of this technology. The plants included the SRC-I plant at Wilsonville, Alabama, which operated from 1974 to 1992; the SRC-I/II plant at Fort Lewis, Washington, which operated from 1974 to 1981; the H-Coal plant at Catlettsburg, Kentucky, which operated from 1980 to 1982; and the Exxon Coal Liquefaction Pilot Plant at Baytown, Texas, which operated from 1980 to 1982. Oak Ridge National Laboratory scientists and engineers were actively involved in many phases and technical disciplines at all four of these plants, especially in materials testing, evaluation, and failure analyses. In addition, ORNL materials scientists and engineers conducted reviews of the demonstration and commercial plant designs for materials selections. The ORNL staff members worked closely with materials engineers at the pilot plants in identifying causes of materials degradation and failures, and in identifying solutions to these problems. This report provides a comprehensive summary of those materials activities. Materials performance data from laboratory and coal liquefaction pilot plant tests, failure analyses, and analyses of components after use in pilot plants were reviewed and assessed to determine the extent and causes of materials degradation in direct coal liquefaction process environments. Reviews of demonstration and commercial plant design documents for materials selections were conducted. These reviews and assessments are presented to capture the knowledge base on the most likely materials of construction for direct coal liquefaction plants.

  19. Test methods for selection of materials of construction for high-level radioactive waste vitrification. Revision

    International Nuclear Information System (INIS)

    Bickford, D.F.; Corbett, R.A.; Morrison, W.S.

    1986-01-01

    Candidate materials of construction were evaluated for a facility at the Department of Energy's Savannah River Plant to vitrify high-level radioactive waste. Limited operating experience was available under the corrosive conditions of the complex vitrification process. The objective of the testing program was to provide a high degree of assurance that equipment will meet or exceed design lifetimes. To meet this objective in reasonable time and minimum cost, a program was designed consisting of a combination of coupon immersion and electrochemical laboratory tests and pilot-scale tests. Stainless steels and nickel-based alloys were tested. Alloys that were most resistant to general and local attack contained nickel, molybdenum (>9%), and chromium (where Cr + Mo > 30%). Alloy C-276 was selected as the reference material for process equipment. Stellite 6 was selected for abrasive service in the presence of formic acid. Alloy 690 and ALLCORR were selected for specific applications

  20. Selection of sorption material for tests of pesticide permeation through protective clothing fabrics.

    Science.gov (United States)

    Krzemińska, Sylwia; Nazimek, Teresa

    2004-01-01

    The paper presents the results of studies on selecting a solid sorption material for absorbing liquid crop protection agents which permeate samples of protective clothing fabrics. The sorption materials were investigated and selected with an assumption that they should have a high recovery coefficient for biologically active substances, used as active ingredients in crop protection agents, at a presumed, acceptably high level. The selected substances were determined with a gas chromatograph equipped with an electron capture detector (dichlorvos, cypermethrin and 2,4-D) and a nitrogen-phosphorus detector (carbofuran). The tests demonstrated that polypropylene melt-blown type unwoven cloth had high recovery coefficients for all 4 active ingredients proposed for the study. The highest recovery coefficient, -.97, was obtained for carbofuran. The recovery coefficients obtained for the 3 remaining substances were lower: .89 for cypermethrin and 2,4-D, and .84 for dichlorvos.

  1. Selective Preparation of trans-Carveol over Ceria Supported Mesoporous Materials MCM-41 and SBA-15

    Directory of Open Access Journals (Sweden)

    Nariman F. Salakhutdinov

    2013-05-01

    Full Text Available Ce-modified mesoporous silica materials MCM-41 and SBA-15, namely 32 wt % Ce–Si–MCM-41, 16 wt % Ce–H–MCM-41 and 20 wt % Ce–Si–SBA-15, were prepared, characterized and studied in the selective preparation of trans-carveol by α-pinene oxide isomerization. The characterizations of these catalysts were performed using scanning electron microscopy, X-ray photoelectron spectroscopy, nitrogen adsorption and FTIR pyridine adsorption. Selective preparation of trans-carveol was carried out in the liquid phase in a batch reactor. The activity and the selectivity of catalyst were observed to be influenced by their acidity, basicity and morphology of the mesoporous materials. The formation of trans-carveol is moreover strongly influenced by the basicity of the used solvent and in order to achieve high yields of this desired alcohol it is necessary to use polar basic solvent.

  2. BIM-Based Decision Support System for Material Selection Based on Supplier Rating

    Directory of Open Access Journals (Sweden)

    Abiola Akanmu

    2015-12-01

    Full Text Available Material selection is a delicate process, typically hinged on a number of factors which can be either cost or environmental related. This process becomes more complicated when designers are faced with several material options of building elements and each option can be supplied by different suppliers whose selection criteria may affect the budgetary and environmental requirements of the project. This paper presents the development of a decision support system based on the integration of building information models, a modified harmony search algorithm and supplier performance rating. The system is capable of producing the cost and environmental implications of different material combinations or building designs. A case study is presented to illustrate the functionality of the developed system.

  3. The Choice Method of Selected Material has influence single evaporation flash method

    International Nuclear Information System (INIS)

    Sunaryo, Geni Rina; Sumijanto; Nurul L, Siti

    2000-01-01

    The final objective of this research is to design the mini scale of desalination installation. It has been started from 1997/1998 and has been doing for this 3 years. Where the study on the assessment of various desalination system has been done in the first year and thermodynamic in the second year. In this third year, literatully study on material resistance from outside pressure has been done. The number of pressure for single evaporator flashing method is mainly depend on the temperature that applied in that system. In this paper, the configuration stage, the choice method of selecting material for main evaporator vessel, tube, tube plates, water boxes, pipework, and valves for multistage flash distillation will be described. The choice of selecting material for MSF is base on economical consideration, cheap, high resistance and easy to be maintained

  4. Petróleo, Royalties e Pobreza

    Directory of Open Access Journals (Sweden)

    Gicélia Mendes da Silva

    2009-08-01

    Full Text Available A exploração do petróleo se constitui num elemento significativo para a economia sergipana. A contradição existente entre o subsolo rico e a população pobre levanta indagações a respeito da gestão destes recursos e as condições de vida da população. Tais condições, aliadas à entrada de novos atores na exploração do petróleo em Sergipe e à gestão dos recursos advindos da exploração, vêm incutindo relações peculiares à política neoliberal na região e em Sergipe. O estudo foi desenvolvido a partir da análise e cruzamento de informações disponíveis na Agência Nacional do Petróleo (ANP, Instituto Brasileiro de Geografia e Estatística (IBGE, Tribunal de Contas da União (TCU e PETROBRAS, dentre outros setores. A carência de políticas sociais que ofereçam às populações condições de inserção nas questões política, econômica e social da região produtora de petróleo tem impedido o desenvolvimento efetivo e mudança no padrão de vida das populações, evidenciando a incoerência entre os altos valores depositados nos cofres públicos municipais decorrentes dos royalties e os elevados índices de pobreza apresentados na região. Tal constatação reforça a ideia de que as políticas públicas devem primar pela redução da desigualdade a partir da gestão responsável dos recursos públicos. Abstract OIL, ROYALTIES AND POVERTY The exploitation of oil has significant element for the Sergipe´s economy. However, the contradiction between the subsoils rich and poor people raises key questions about the management of these resources and the living conditions of the population. Such conditions, the entry of new actors in the scenery for the exploration of oil in Sergipe and the management of resources of exploration, instilling relations peculiar to neo-liberal policy in the region and in Sergipe. The study was developed from the analysis and crossing of information available in the national agency oil (ANP

  5. «Somos petróleo»

    OpenAIRE

    Drum, Duskin

    2017-01-01

    Resumen «Somos petróleo» es un experimento de práctica-como-investigación creado para indagar sobre la manera como los norteamericanos conceptualizan sus relaciones con el petróleo. Durante el performance los participantes leyeron en voz alta emulaciones del testimonio diplomático Gwich'in sobre ser pueblo caribú. En las emulaciones, el texto es el mismo salvo que se reemplaza la palabra «caribú» por «petróleo». Los Gwich'in son un pueblo indígena cuyas tierras de origen se sitúan en el nores...

  6. Corrosion of Selected Materials in Boiling Sulfuric Acid for the Nuclear Power Industries

    International Nuclear Information System (INIS)

    Kim, Dong Jin; Lee, Han Hee; Kwon, Hyuk Chul; Kim, Hong Pyo; Hwang, Seong Sik

    2007-01-01

    Iodine sulfur (IS) process is one of the promising processes for a hydrogen production by using a high temperature heat generated by a very high temperature gas cooled reactor(VHTR) in the nuclear power industries. Even though the IS process is very efficient for a hydrogen production and it is not accompanied by a carbon dioxide evolution, the highly corrosive environment of the process limits its application in the industry. Corrosion tests of selected materials were performed in sulfuric acid to select appropriate materials compatible with the IS process. The materials used in this work were Fe-Cr alloys, Fe-Ni-Cr alloys, Fe-Si alloys, Ni base alloys, Ta, Ti, Zr, SiC, Fe-Si, etc. The test environments were 50 wt% sulfuric acid at 120 .deg. C and 98 wt% at 320 .deg. C. Corrosion rates were measured by using a weight change after an immersion. The surface morphologies and cross sectional areas of the corroded materials were examined by using SEM equipped with EDS. Corrosion behaviors of the materials were discussed in terms of the chemical composition of the materials, a weight loss, the corrosion morphology, the precipitates in the microstructure and the surface layer composition

  7. Assessment of Heat Hazard during the Polymerization of Selected Light-Sensitive Dental Materials.

    Science.gov (United States)

    Janeczek, Maciej; Herman, Katarzyna; Fita, Katarzyna; Dudek, Krzysztof; Kowalczyk-Zając, Małgorzata; Czajczyńska-Waszkiewicz, Agnieszka; Piesiak-Pańczyszyn, Dagmara; Kosior, Piotr; Dobrzyński, Maciej

    2016-01-01

    Introduction. Polymerization of light-cured dental materials used for restoration of hard tooth tissue may lead to an increase in temperature that may have negative consequence for pulp vitality. Aim. The aim of this study was to determine maximum temperatures reached during the polymerization of selected dental materials, as well as the time that is needed for samples of sizes similar to those used in clinical practice to reach these temperatures. Materials and Methods. The study involved four composite restorative materials, one lining material and a dentine bonding agent. The polymerization was conducted with the use of a diode light-curing unit. The measurements of the external surface temperature of the samples were carried out using the Thermovision®550 thermal camera. Results. The examined materials significantly differed in terms of the maximum temperatures values they reached, as well as the time required for reaching the temperatures. A statistically significant positive correlation of the maximum temperature and the sample weight was observed. Conclusions. In clinical practice, it is crucial to bear in mind the risk of thermal damage involved in the application of light-cured materials. It can be reduced by using thin increments of composite materials.

  8. Assessment of Heat Hazard during the Polymerization of Selected Light-Sensitive Dental Materials

    Directory of Open Access Journals (Sweden)

    Maciej Janeczek

    2016-01-01

    Full Text Available Introduction. Polymerization of light-cured dental materials used for restoration of hard tooth tissue may lead to an increase in temperature that may have negative consequence for pulp vitality. Aim. The aim of this study was to determine maximum temperatures reached during the polymerization of selected dental materials, as well as the time that is needed for samples of sizes similar to those used in clinical practice to reach these temperatures. Materials and Methods. The study involved four composite restorative materials, one lining material and a dentine bonding agent. The polymerization was conducted with the use of a diode light-curing unit. The measurements of the external surface temperature of the samples were carried out using the Thermovision®550 thermal camera. Results. The examined materials significantly differed in terms of the maximum temperatures values they reached, as well as the time required for reaching the temperatures. A statistically significant positive correlation of the maximum temperature and the sample weight was observed. Conclusions. In clinical practice, it is crucial to bear in mind the risk of thermal damage involved in the application of light-cured materials. It can be reduced by using thin increments of composite materials.

  9. Characterization of rich in calcium materials using X-ray selective absorbers

    International Nuclear Information System (INIS)

    Guereca, G.; Ruvalcaba, J.L.

    2004-01-01

    For Particle Induced X-ray Emission Spectroscopy (PIXE) and X-ray Fluorescence Technique (FRX), the analysis of materials rich in one or two elements may present some difficulties due to high counting rates and saturation effects in X-ray detectors. In this case, it is possible to use selective absorbers in order to reduce the intensity of the major elements with low attenuation for the X-rays of other elements of the material. Using selective absorbers, the detection limits and the sensitivity are increased. For rich Ca materials (shells, bone, teeth and stucco, for instance), the high intensity of Ca X-rays interferes with the detection of lighter and heavier elements. Cl, Ar and Ag compounds are good candidates for Ca selective absorbers, but only Ag and Ar may have a practical absorber thickness. A selective absorber for Ca X-rays using a combination of thin Ag films and a flux of Ar and He was tested at the external beam setup of the Tandem Pelletron Accelerator for PIXE measurements. The improvement on elements detection on bone and colored stucco is shown. (Author) 8 refs., 2 tabs., 8 figs

  10. Normalization Methods and Selection Strategies for Reference Materials in Stable Isotope Analyes. Review

    Energy Technology Data Exchange (ETDEWEB)

    Skrzypek, G. [West Australian Biogeochemistry Centre, John de Laeter Centre of Mass Spectrometry, School of Plant Biology, University of Western Australia, Crawley (Australia); Sadler, R. [School of Agricultural and Resource Economics, University of Western Australia, Crawley (Australia); Paul, D. [Department of Civil Engineering (Geosciences), Indian Institute of Technology Kanpur, Kanpur (India); Forizs, I. [Institute for Geochemical Research, Hungarian Academy of Sciences, Budapest (Hungary)

    2013-07-15

    Stable isotope ratio mass spectrometers are highly precise, but not accurate instruments. Therefore, results have to be normalized to one of the isotope scales (e.g., VSMOW, VPDB) based on well calibrated reference materials. The selection of reference materials, numbers of replicates, {delta}-values of these reference materials and normalization technique have been identified as crucial in determining the uncertainty associated with the final results. The most common normalization techniques and reference materials have been tested using both Monte Carlo simulations and laboratory experiments to investigate aspects of error propagation during the normalization of isotope data. The range of observed differences justifies the need to employ the same sets of standards worldwide for each element and each stable isotope analytical technique. (author)

  11. Material radioassay and selection for the XENON1T dark matter experiment

    Energy Technology Data Exchange (ETDEWEB)

    Aprile, E.; Anthony, M.; De Perio, P.; Gao, F.; Goetzke, L.W.; Greene, Z.; Lin, Q.; Messina, M.; Plante, G.; Rizzo, A.; Zhang, Y. [Columbia University, Physics Department, New York, NY (United States); Aalbers, J.; Breur, P.A.; Brown, A.; Colijn, A.P.; Decowski, M.P.; Hogenbirk, E.; Tiseni, A. [Nikhef and the University of Amsterdam, Amsterdam (Netherlands); Agostini, F. [INFN-Laboratori Nazionali del Gran Sasso, L' Aquila (Italy); Gran Sasso Science Institute, L' Aquila (Italy); University of Bologna, Department of Physics and Astrophysics, Bologna (Italy); INFN-Bologna (Italy); Alfonsi, M.; Geis, C.; Grignon, C.; Oberlack, U.; Scheibelhut, M.; Schindler, S. [Johannes Gutenberg-Universitaet Mainz, Institut fuer Physik and Exzellenzcluster PRISMA, Mainz (Germany); Amaro, F.D.; Cardoso, J.M.R.; Lopes, J.A.M.; Santos, J.M.F. dos; Silva, M. [University of Coimbra, LIBPhys, Department of Physics, Coimbra (Portugal); Arneodo, F.; Benabderrahmane, M.L.; Maris, I. [New York University Abu Dhabi, Abu Dhabi (United Arab Emirates); Barrow, P.; Baudis, L.; Di Giovanni, A.; Franco, D.; Galloway, M.; Kessler, G.; Kish, A.; Mayani, D.; Pakarha, P.; Piastra, F.; Wei, Y.; Wulf, J. [University of Zurich, Physik Institut, Zurich (Switzerland); Bauermeister, B. [Johannes Gutenberg-Universitaet Mainz, Institut fuer Physik and Exzellenzcluster PRISMA, Mainz (Germany); Stockholm University, AlbaNova, Oskar Klein Centre, Department of Physics, Stockholm (Sweden); Berger, T.; Brown, E.; Piro, M.C. [Rensselaer Polytechnic Institute, Department of Physics, Applied Physics and Astronomy, Troy, NY (United States); Sivers, M. von [Rensselaer Polytechnic Institute, Troy, NY (United States). Dept. of Physics, Applied Physics and Astronomy; Bern Univ. (Switzerland). Albert Einstein Center for Fundamental Physics; Bruenner, S.; Cichon, D.; Eurin, G.; Hasterok, C.; Lindemann, S.; Lindner, M.; Marrodan Undagoitia, T.; Pizzella, V.; Rauch, L.; Rupp, N.; Schreiner, J.; Simgen, H. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Bruno, G.; Gallo Rosso, A.; Molinario, A.; Laubenstein, M.; Nisi, S. [INFN-Laboratori Nazionali del Gran Sasso, L' Aquila (Italy); Gran Sasso Science Institute, L' Aquila (Italy); Budnik, R.; Itay, R.; Landsman, H.; Lellouch, D.; Levinson, L.; Manfredini, A.; Priel, N. [Weizmann Institute of Science, Department of Particle Physics and Astrophysics, Rehovot (Israel); Buetikofer, L.; Coderre, D.; Kaminsky, B.; Schumann, M. [Universitaet Freiburg, Physikalisches Institut, Freiburg (Germany); Calven, J.; Conrad, J.; Ferella, A.D.; Pelssers, B. [Stockholm University, AlbaNova, Oskar Klein Centre, Department of Physics, Stockholm (Sweden); Cervantes, M.; Lang, R.F.; Masson, D.; Pienaar, J.; Reichard, S.; Reuter, C. [Purdue University, Department of Physics and Astronomy, West Lafayette, IN (United States); Cussonneau, J.P.; Diglio, S.; Le Calloch, M.; Masbou, J.; Micheneau, K.; Persiani, R.; Thers, D. [Universite de Nantes, SUBATECH, Ecole des Mines de Nantes, CNRS/IN2P3, Nantes (France); Di Gangi, P.; Garbini, M.; Massoli, F.V.; Sartorelli, G.; Selvi, M. [University of Bologna, Department of Physics and Astrophysics, Bologna (Italy); INFN-Bologna (Italy); Fei, J.; Ni, K.; Ye, J. [University of California, Department of Physics, San Diego, CA (United States); Fieguth, A.; Murra, M.; Rosendahl, S.; Weinheimer, C. [Westfaelische Wilhelms-Universitaet Muenster, Institut fuer Kernphysik, Muenster (Germany); Fulgione, W. [INFN-Laboratori Nazionali del Gran Sasso, L' Aquila (Italy); Gran Sasso Science Institute, L' Aquila (Italy); INFN-Torino (Italy); Osservatorio Astrofisico di Torino, Torino (Italy); Grandi, L.; Saldanha, R.; Shockley, E.; Upole, N. [University of Chicago, Department of Physics and Kavli Institute of Cosmological Physics, Chicago, IL (United States); Miguez, B.; Trinchero, G. [INFN-Torino (Italy); Osservatorio Astrofisico di Torino, Torino (Italy); Naganoma, J.; Shagin, P. [Rice University, Department of Physics and Astronomy, Houston, TX (United States); Scotto Lavina, L. [Universite Pierre et Marie Curie, Universite Paris Diderot, CNRS/IN2P3, LPNHE, Paris (France); Stein, A.; Wang, H. [University of California, Physics and Astronomy Department, Los Angeles, CA (United States); Tunnell, C. [Nikhef and the University of Amsterdam, Amsterdam (Netherlands); University of Chicago, Department of Physics and Kavli Institute of Cosmological Physics, Chicago, IL (United States); Collaboration: XENON Collaboration

    2017-12-15

    The XENON1T dark matter experiment aims to detect weakly interacting massive particles (WIMPs) through low-energy interactions with xenon atoms. To detect such a rare event necessitates the use of radiopure materials to minimize the number of background events within the expected WIMP signal region. In this paper we report the results of an extensive material radioassay campaign for the XENON1T experiment. Using gamma-ray spectroscopy and mass spectrometry techniques, systematic measurements of trace radioactive impurities in over one hundred samples within a wide range of materials were performed. The measured activities allowed for stringent selection and placement of materials during the detector construction phase and provided the input for XENON1T detection sensitivity estimates through Monte Carlo simulations. (orig.)

  12. Radiation tests at cryogenic temperature on selected organic materials for LHC

    International Nuclear Information System (INIS)

    Humer, K.; Weber, H.W.; Szeless, B.; Tavlet, M.

    1997-01-01

    Future multi-TeV particle accelerators like the CERN Large Hadron Collider (LHC) will use superconducting magnets in which organic materials will be exposed to high radiation levels at temperatures as low as 2 K. A representative selection of organic materials comprising insulating films, cable insulations, epoxy resins and composites were exposed to neutron and gamma radiation of a nuclear reactor. Depending on the type of materials, the integrated radiation doses varied between 180 kGy and 155 MGy. During irradiation, the samples were kept close to the boiling temperature of liquid nitrogen, i.e. at 80 K, and thereafter stored in liquid nitrogen and transferred at the same temperature into the testing device for measurement of tensile and flexural strength. Tests were carried out on the same materials at similar dose rates at room temperature, and the results are compared with the ones obtained at cryogenic temperature. They show that within the selected dose range, a number of organic materials are suitable for use in radiation fields of the LHC at cryogenic temperature

  13. Selection of contact bearing couple materials for hip prosthesis using finite element analysis under static conditions

    Science.gov (United States)

    Arirajan, K. A.; Chockalingam, K.; Vignesh, C.

    2018-04-01

    Implants are the artificial parts to replace the missing bones or joints in human anatomy to give mechanical support. Hip joint replacement is an important issue in orthopaedic surgery. The main concern limiting the long-run success of the total hip replacement is the limited service life. Hip replacement technique is widely used in replacing the femur head and acetabular cup by materials that are highly biocompatible. The success of the artificial hip replacement depends upon proper material selection, structure, and shape of the hip prosthesis. Many orthopaedic analyses have been tried with different materials, but ended with partial success on the application side. It is a critical task for selecting the best material pair in the hip prosthesis design. This work develops the finite element analysis of an artificial hip implant to study highest von Mises stress, contact pressure and elastic strain occurs for the dissimilar material combination. The different bearing couple considered for the analysis are Metal on Metal, Metal on Plastic, Metal on Ceramic, Ceramic on Plastic, Ceramic on Ceramic combinations. The analysis is carried out at different static positions of a human (i.e) standing, sitting. The results reveals that the combination with metal in contact with plastic (i.e) Titanium femoral head paired with Ultra High Molecular Weight Poly Ethylene acetabular cup reduces maximum von Mises stress and also it gives lowest contact pressure than other combination of bearing couples.

  14. Selection and evaluation of inner material candidates for Spanish high level radioactive waste canisters

    International Nuclear Information System (INIS)

    Puig, Francesc; Dies, Javier; Sevilla, Manuel; Pablo, Joan de; Pueyo, Juan Jose; Miralles, Lourdes; Martinez-Esparza, Aurora

    2007-01-01

    This paper summarizes the work carried out to analyse different alternatives related to the inner material selection of the Spanish high level waste canister for long term storage. The preliminary repository design considers granitic or clay formations, compacted bentonite sealing, corrosion allowing steel canisters and glass bead filling between the fuel assemblies and canister walls. This filling material will have the primary role of avoiding the possibility of a criticality event, which becomes an issue of major importance once the container is finally breached by corrosion and flooded by groundwater. In the first place, a complete set of requirements have been devised as evaluation criteria for candidate materials examination and selection; resulting in a compilation of demands significantly deeper and more exhaustive than any other similar work found in literature, including over 20 requirements and some other general aspects that could involve improvements in repository performance. Secondly, eight materials or material families (cast iron or steel, borosilicate glass, spinel, depleted uranium, dehydrated zeolites, hematite, phosphates and olivine) have been chosen and examined in detail, extracting some relevant conclusions. Either cast iron, borosilicate glass, spinel or depleted uranium are considered to look quite promising for the mentioned purpose. (authors)

  15. Selection of materials using multi-criteria decision-making methods with minimum data

    Directory of Open Access Journals (Sweden)

    Shankar Chakraborty

    2013-07-01

    Full Text Available Selection of material for a specific engineering component, which plays a significant role in its design and proper functioning, is often treated as a multi-criteria decision-making (MCDM problem where the most suitable material is to be chosen based on a given set of conflicting criteria. For solving these MCDM problems, the designers do not generally know what should be the optimal number of criteria required for arriving at the best decisive action. Those criteria should be independent to each other and their number should usually limit to seven plus or minus two. In this paper, five material selection problems are solved using three common MCDM techniques to demonstrate the effect of number of criteria on the final rankings of the material alternatives. It is interesting to observe that the choices of the best suited materials solely depend on the criterion having the maximum priority value. It is also found that among the three MCDM methods, the ranking performance of VIKOR (Vlse Kriterijumska Optimizacija Kompromisno Resenje method is the best.

  16. A matrix in life cycle perspective for selecting sustainable materials for buildings in Sri Lanka

    Energy Technology Data Exchange (ETDEWEB)

    Abeysundara, U.G. Yasantha [Ministry of Education, Isurupaya, Battaramulla (Sri Lanka); Babel, Sandhya [Environmental Technology Program, School of Biochemical Engineering and Technology, Sirindhorn International Institute of Technology, Thammasat University, P.O. Box 22, Pathumthani 12121 (Thailand); Gheewala, Shabbir [The Joint Graduate School of Energy and Environment, King Mongkut' s University of Technology Thonburi, Bangkok 10140 (Thailand)

    2009-05-15

    This paper presents a matrix to select sustainable materials for buildings in Sri Lanka, taking into consideration environmental, economic and social assessments of materials in a life cycle perspective. Five building elements, viz., foundations, roofs, ceilings, doors and windows, and floors are analyzed based on materials used for these elements. Environmental burdens associated with these elements are analyzed in terms of embodied energy and environmental impacts such as global warming, acidification and nutrient enrichment. Economic analysis is based on market prices and affordability of materials. Social factors that are taken into account are thermal comfort, interior (aesthetics), ability to construct quickly, strength and durability. By compiling the results of analyses, two building types with minimum and maximum impacts are identified. These two cases along with existing buildings are compared in a matrix of environmental, economic and social scores. Analysis of the results also indicates need for higher consideration of environmental parameters in decision-making over social and economic factors, as social and economic scores do not vary much between cases. Hence, this matrix helps decision-makers to select sustainable materials for buildings, meaningfully, and thus helps to move towards a more sustainable buildings and construction sector. (author)

  17. Results of radiation tests at cryogenic temperature on some selected organic materials for the LHC

    International Nuclear Information System (INIS)

    Schoenbacher, H.; Szeless, B.; Tavlet, M.; Humer, K.; Weber, H.W.

    1996-01-01

    Future multi-TeV particle accelerators like the CERN Large Hadron Collider (LHC) will use superconducting magnets where organic materials will be exposed to high radiation levels at temperatures as low as 2 K. A representative selection of organic materials comprising insulating films, cable insulations, and epoxy-type impregnated resins were exposed to neutron and gamma radiation of a nuclear reactor. Depending on the type of materials, the integrated radiation doses varied between 180 kGy and 155 MGy. During irradiation, the samples were kept close to the boiling temperature of liquid nitrogen i.e. ∼ 80 K and thereafter stored in liquid nitrogen and transferred at the same temperature into the testing device for measurement of tensile and flexural strength. Tests were carried out on the same materials at similar dose rates at room temperature, and the results were compared with those obtained at cryogenic temperature. They show that, within the selected dose range, a number of organic materials are suitable for use in the radiation field of the LHC at cryogenic temperature. (orig.)

  18. Performances of Saft Lithium-Ion Cells in LEO Cycling

    Directory of Open Access Journals (Sweden)

    Prevot D.

    2017-01-01

    The article will thus present the whole LEO cycling results available for the two cells, and will provide afterwards the correlation status of Saft Li-ion Model (SLIM with all the experimental data acquired.

  19. Windscale inquiry. A selected list of material based on the DOE/DTp library

    Energy Technology Data Exchange (ETDEWEB)

    Lambert, C M [comp.

    1981-01-01

    The nuclear debate, far from being concluded by the Windscale decision, was in fact opened up and its scope widened to take into account the political, international, environmental and social issues involved. This debate continues and the selection of literature presented here aims to illustrate all aspects of the Inquiry and its implications. The material is presented in two main sections. Section A is concerned with the Inquiry itself: the proceedings, the report and the government's decision. Section B presents a selection of the literature and debate that resulted.

  20. Porous glasses as a host of luminescent materials, their applications and site selective determination

    Energy Technology Data Exchange (ETDEWEB)

    Reisfeld, Renata, E-mail: renata.reisfeld@mail.huji.ac.il [Institute of Chemistry, Hebrew University of Jerusalem, Givat-Ram, Jerusalem 91904 (Israel); Jasinska, Bozena [Institute of Physics, Maria Curie-Sklodowska University, Pl. M. Curie-Skłodowsskiej 1, 20-031 Lublin (Poland); Levchenko, Viktoria [Institute of Chemistry, Hebrew University of Jerusalem, Givat-Ram, Jerusalem 91904 (Israel); Gorgol, Marek [Institute of Physics, Maria Curie-Sklodowska University, Pl. M. Curie-Skłodowsskiej 1, 20-031 Lublin (Poland); Saraidarov, Tsiala; Popov, Inna [Institute of Chemistry, Hebrew University of Jerusalem, Givat-Ram, Jerusalem 91904 (Israel); Antropova, Tatiana [I. V. Grebenshchikov Institute of the Chemistry of Silicates, Russian Academy of Sciences, Nab. Makarova, 2, Liter B, Saint-Petersburg 199034 (Russian Federation); Rysiakiewicz-Pasek, Ewa [Institute of Physics, Wroclaw University of Technology, W. Wyspianskiego 27, 50-370 Wroclaw (Poland)

    2016-01-15

    The site selective distribution of pore sizes in pure porous glasses and glasses doped by a luminescent colorant is determined by luminescent spectroscopy, SEM, SAXS and PALS. The potential applications of the studied materials as environmental and biological sensors are outlined. We suggest how luminescent porous glasses doped by complexes of Gd can act as solid scintillators in tracing elementary particles like neutrino. - Highlights: • Porous glasses are a medium for large number of luminescent materials. • Size distribution of empty and filled pores is studied. • The validity of data obtained by different methods is analyzed.

  1. Factors in the selection of broiler tube materials for a civil fast reactor

    Energy Technology Data Exchange (ETDEWEB)

    Tyzack, C; Chitty, A

    1975-07-01

    This paper briefly considers some of the factors which must be balanced in the selection of a boiler tube material for a Civil Fast Reactor. The merits and possible demerits of low alloy ferritic steels and the austenitic Alloy 800 are compared with respect to waterside corrosion resistance, mechanical properties, fabrication and weldability and possible effects of exposure to the sodium environment under normal and fault conditions. It is pointed out that although there is operational experience of most of the materials in boiler superheater applications there is little or none in evaporative regimes. (author)

  2. Results of radiation tests at cryogenic temperature on some selected organic materials for the LHC

    International Nuclear Information System (INIS)

    Tavlet, M.; Schoenbacher, H.

    1999-01-01

    In the near future, particle accelerators and detectors as well as fusion reactors will operate at cryogenic temperatures. At temperatures as low as 2 K, the organic materials used for the insulation of the superconducting magnets and cables will be exposed to high radiation levels. In this work, a representative selection of organic materials comprising insulating films, cable insulations and epoxy-type-impregnated resins were exposed to neutron and gamma radiation of nuclear reactors, both at ambient and cryogenic temperatures, and were subsequently mechanically tested. The results show that the radiation degradation is never worse in a cryogenic fluid than it is in usual ambient conditions. (author)

  3. Safety Standard for Oxygen and Oxygen Systems: Guidelines for Oxygen System Design, Materials Selection, Operations, Storage, and Transportation

    Science.gov (United States)

    1996-01-01

    NASA's standard for oxygen system design, materials selection, operation, and transportation is presented. Minimum guidelines applicable to NASA Headquarters and all NASA Field Installations are contained.

  4. The Influence of Free Space Environment in the Mission Life Cycle: Material Selection

    Science.gov (United States)

    Edwards, David L.; Burns, Howard D.; de Groh, Kim K.

    2014-01-01

    The natural space environment has a great influence on the ability of space systems to perform according to mission design specification. Understanding the natural space environment and its influence on space system performance is critical to the concept formulation, design, development, and operation of space systems. Compatibility with the natural space environment is a primary factor in determining the functional lifetime of the space system. Space systems being designed and developed today are growing in complexity. In many instances, the increased complexity also increases its sensitivity to space environmental effects. Sensitivities to the natural space environment can be tempered through appropriate design measures, material selection, ground processing, mitigation strategies, and/or the acceptance of known risks. The design engineer must understand the effects of the natural space environment on the space system and its components. This paper will discuss the influence of the natural space environment in the mission life cycle with a specific focus on the role of material selection.

  5. Effect of material selection and background impurity on interface property and resulted CIP-GMR performance

    International Nuclear Information System (INIS)

    Peng Xilin; Morrone, Augusto; Nikolaev, Konstantin; Kief, Mark; Ostrowski, Mark

    2009-01-01

    In this paper, we investigated the effect of background base pressure, wafer-transferring time between process modules, and stack layer material selection on the current-in-plane giant magneto-resistive (CIP-GMR) interface properties and the resulted CIP-GMR performance. Experimental results showed that seed layer/AFM interface, AFM/pinned layer (PL) interface, pinned layer/Ru interface, and reference layer (RL)/Cu spacer interface are among the most critical ones for a CIP-GMR device. By reducing the background impurity level (water moisture and oxygen), optimizing the wafer process flow sequence, and careful stack-layer material selection, such critical interfaces in a CIP-GMR device can be preserved. Consequently, a much robust GMR performance control can be achieved.

  6. Corrosion test plan to guide canister material selection and design for a tuff repository

    International Nuclear Information System (INIS)

    McCright, R.D.; van Konynenburg, R.A.; Ballou, L.B.

    1983-11-01

    Corrosion rates and the mode of corrosion attack form a most important basis for selection of canister materials and design of a nuclear waste package. Type 304L stainless steel was selected as the reference material for canister fabrication because of its generally excellent corrosion resistance in water, steam and air. However, 304L may be susceptible to localized and stress-assisted forms of corrosion under certain conditions. Alternative alloys are also investigated; these alloys were chosen because of their improved resistance to these forms of corrosion. The fabrication and welding processes, as well as the glass pouring operation for defense and commercial high-level wastes, may influence the susceptibility of the canister to localized and stress forms of corrosion. 12 references, 2 figures, 4 tables

  7. Material Selection for Cable Gland to Improved Reliability of the High-hazard Industries

    Science.gov (United States)

    Vashchuk, S. P.; Slobodyan, S. M.; Deeva, V. S.; Vashchuk, D. S.

    2018-01-01

    The sealed cable glands (SCG) are available to ensure safest connection sheathed single wire for the hazard production facility (nuclear power plant and others) the same as pilot cable, control cables, radio-frequency cables et al. In this paper, we investigate the specifics of the material selection of SCG with the express aim of hazardous man-made facility. We discuss the safe working conditions for cable glands. The research indicates the sintering powdered metals cables provide the reliability growth due to their properties. A number of studies have demonstrated the verification of material selection. On the face of it, we make findings indicating that double glazed sealed units could enhance reliability. We had evaluated sample reliability under fire conditions, seismic load, and pressure containment failure. We used the samples mineral insulated thermocouple cable.

  8. Betsy Pugel, Tiny houses: Planetary protection-focused materials selection for spaceflight hardware surfaces

    OpenAIRE

    Schriml, Lynn

    2017-01-01

    Betsy Pugel, National Aeronautics and Space Administration Tiny houses: Planetary protection-focused materials selection for spaceflight hardware surfacesOn October 10-12th, 2017 the Alfred P. Sloan Foundation and The National Academies of Sciences, Engineering and Medicine co-hosting MoBE 2017 (Microbiology of the Built Environment Research and Applications Symposium) at the National Academy of Sciences Building to present the current state-of-the-science in understanding the formation and ...

  9. Iodine-labelling of albumin and fibrinogen and application in selecting implantable material-titanium oxide

    International Nuclear Information System (INIS)

    Liu Fangyan; Zhou Meiying; Zhang Feng

    1998-01-01

    Human serum albumin and fibrinogen were successfully labelled with 125 I. The labelled proteins were further applied to carry out a background study on the selection of the blood-compatible materials. The protein adsorption of four kinds of titanium oxide film was determined and compared. It was found that Sample B can adsorb more albumin and less fibrinogen than other three samples and hold the adsorbed albumin most stably

  10. Automating Risk Assessments of Hazardous Material Shipments for Transportation Routes and Mode Selection

    International Nuclear Information System (INIS)

    Dolphin, Barbara H.; Richins, William D.; Novascone, Stephen R.

    2010-01-01

    The METEOR project at Idaho National Laboratory (INL) successfully addresses the difficult problem in risk assessment analyses of combining the results from bounding deterministic simulation results with probabilistic (Monte Carlo) risk assessment techniques. This paper describes a software suite designed to perform sensitivity and cost/benefit analyses on selected transportation routes and vehicles to minimize risk associated with the shipment of hazardous materials. METEOR uses Monte Carlo techniques to estimate the probability of an accidental release of a hazardous substance along a proposed transportation route. A METEOR user selects the mode of transportation, origin and destination points, and charts the route using interactive graphics. Inputs to METEOR (many selections built in) include crash rates for the specific aircraft, soil/rock type and population densities over the proposed route, and bounding limits for potential accident types (velocity, temperature, etc.). New vehicle, materials, and location data are added when available. If the risk estimates are unacceptable, the risks associated with alternate transportation modes or routes can be quickly evaluated and compared. Systematic optimizing methods will provide the user with the route and vehicle selection identified with the lowest risk of hazardous material release. The effects of a selected range of potential accidents such as vehicle impact, fire, fuel explosions, excessive containment pressure, flooding, etc. are evaluated primarily using hydrocodes capable of accurately simulating the material response of critical containment components. Bounding conditions that represent credible accidents (i.e; for an impact event, velocity, orientations, and soil conditions) are used as input parameters to the hydrocode models yielding correlation functions relating accident parameters to component damage. The Monte Carlo algorithms use random number generators to make selections at the various decision

  11. An Elementary Overview of the Selection of Materials for Service in Oxygen-Enriched Environments

    Science.gov (United States)

    Davis, Samuel Eddie

    2012-01-01

    The process for selecting materials for use in oxygen or oxygen-enriched environments is one that continues to be investigated by many industries due to the importance to those industries of oxygen systems. There are several excellent resources available to assist oxygen systems design engineers and end-users, with the most comprehensive being ASTM MNL-36, Safe Use of Oxygen and Oxygen Systems: Handbook for Design, Operation and Maintenance, 2nd Edition. ASTM also makes available several standards for oxygen systems. However, the ASTM publications are extremely detailed, and typically designed for professionals who already possess a working knowledge of oxygen systems. No notable resource exists, whether an ASTM or other organizational publication, which can be used to educate engineers or technicians who have no prior knowledge of the nuances of oxygen system design and safety. This paper will fill the void for information needed by organizations that design or operate oxygen systems. The information in this paper is not new information, but is a concise and easily understood summary of selecting materials for oxygen systems. This paper will serve well as an employee s first introduction to oxygen system materials selection, and probably the employee s first introduction to ASTM.

  12. Generation IV and transmutation materials (GETMAT) project: First assessment of selected results

    International Nuclear Information System (INIS)

    Fazio, Concetta; Serrano, Marta; Gessi, Alessandro; Henry, Jean; Malerba, Lorenzo

    2015-01-01

    The Generation IV and Transmutation Material (GETMAT) project has been initiated within the 7. EURATOM framework programme with the objective to support the development of innovative reactor designs. Emphasis has been put on the investigation, both in the theoretical and experimental domains, of selected material properties that are cross-cutting among the various Generation IV and Transmutation systems. The selection of the properties to be investigated has been performed by identifying relevant conditions of key components as cores and primary systems. Moreover, taking into account the envisaged conditions of these components it turned out that innovative materials might be a better choice with respect to conventional nuclear grade steels. Therefore, ODS alloys and 9-12 Cr Ferritic/Martensitic (F/M) steels have been selected as reference for the GETMAT project. The R and D activities have been focused on basic characterisation of ODS alloys produced ad hoc for the project and on an extensive PIE programme of F/M steels irradiated in previous programmes. Finally, first principle modelling studies to explain irradiation hardening and embrittlement of F/M alloys were an additional important task. The objective of this manuscript is to make a first assessment of the results obtained within GETMAT. (authors)

  13. Novel porous carbon materials with ultrahigh nitrogen contents for selective CO 2 capture

    KAUST Repository

    Zhao, Yunfeng; Zhao, Lan; Yao, Kexin; Yang, Yang; Zhang, Qiang; Han, Yu

    2012-01-01

    Nitrogen-doped carbon materials were prepared by a nanocasting route using tri-continuous mesoporous silica IBN-9 as a hard template. Rationally choosing carbon precursors and carefully controlling activation conditions result in an optimized material denoted as IBN9-NC1-A, which possesses a very high nitrogen doping concentration (∼13 wt%) and a large surface area of 890 m 2 g -1 arising from micropores (<1 nm). It exhibits an excellent performance for CO 2 adsorption over a wide range of CO 2 pressures. Specifically, its equilibrium CO 2 adsorption capacity at 25 °C reaches up to 4.50 mmol g -1 at 1 bar and 10.53 mmol g -1 at 8 bar. In particular, it shows a much higher CO 2 uptake at low pressure (e.g. 1.75 mmol g -1 at 25 °C and 0.2 bar) than any reported carbon-based materials, owing to its unprecedented nitrogen doping level. The high nitrogen contents also give rise to significantly enhanced CO 2/N 2 selectivities (up to 42), which combined with the high adsorption capacities, make these new carbon materials promising sorbents for selective CO 2 capture from power plant flue gas and other relevant applications. © 2012 The Royal Society of Chemistry.

  14. Material selection for elastic energy absorption in origami-inspired compliant corrugations

    International Nuclear Information System (INIS)

    Tolman, Sean S; Delimont, Isaac L; Howell, Larry L; Fullwood, David T

    2014-01-01

    Elastic absorption of kinetic energy and distribution of impact forces are required in many applications. Recent attention to the potential for using origami in engineering may provide new methods for energy absorption and force distribution. A three-stage strategy is presented for selecting materials for such origami-inspired designs that can deform to achieve a desired motion without yielding, absorb elastic strain energy, and be lightweight or cost effective. Two material indices are derived to meet these requirements based on compliant mechanism theory. Finite element analysis is used to investigate the effects of the material stiffness in the Miura-ori tessellation on its energy absorption and force distribution characteristics compared with a triangular wave corrugation. An example is presented of how the method can be used to select a material for a general energy absorption application of the Miura-ori. Whereas the focus of this study is the Miura-ori tessellation, the methods developed can be applied to other tessellated patterns used in energy absorbing or force distribution applications. (paper)

  15. Guidelines for selecting preferred highway routes for highway-route-controlled quantity shipments of radioactive materials

    International Nuclear Information System (INIS)

    1989-01-01

    The document presents guidelines for use by State officials in selecting preferred routes for highway route controlled quantity shipments of radioactive materials. A methodology for analyzing and comparing safety factors of alternative routes is described. Technical information on the impacts of radioactive material transportation needed to apply the methodology is also presented. Application of the methodology will identify the route (or set of routes) that minimizes the radiological impacts from shipments of these radioactive materials within a given State. Emphasis in the document is on practical application of the methodology. Some details of the derivation of the methods and data are presented in the appendices. All references in the body of the report can be found listed in the Bibliography (Appendix F)

  16. Evaluation of functional substances in the selected food materials for space agriculture

    Science.gov (United States)

    Tomita-Yokotani, Kaori; Kimura, Yasuko; Yamashita, Masamichi; Kimura, Shunta; Sato, Seigo; Katoh, Hiroshi; Abe, Yusuke; Ajioka, Reiko

    We have been studying the useful life-support system in closed bio-ecosystem for space agriculture. We have already proposed the several species as food material, such as Nostoc sp. HK-01 and Prunnus sp., cyanobacterium and Japanese cherry tree, respectively. The cyanobacterium, Nostoc sp Hk-01, has high tolerances to several space environment. Furthermore, the woody plant materials have useful utilization elements in our habitation environment. The studies of woody plants under a space-environment in the vegetable kingdom have a high contribution to the study of various and exotic environmental responses, too. We have already found that they can produce the important functional substances for human. Here, we will show the evaluation of functional substances in the selected food materials under the possible conditions for space agriculture after cooking.

  17. Selection and durability of seal materials for a bedded salt repository: preliminary studies

    International Nuclear Information System (INIS)

    Roy, D.M.; Grutzeck, M.W.; Wakeley, L.D.

    1983-11-01

    This report details preliminary results of both experimental and theoretical studies of cementitious seal materials for use in a proposed nuclear waste repository in bedded salt. Effects of changes in bulk composition and environment upon phase stability and physical/mechanical properties have been evaluated for more than 25 formulations. Bonding and interfacial characteristics of the region between host rock and seal material or concrete aggregate and cementitious matrix for selected formulations have been studied. Compatibilities of clays and zeolites in brines typical of the SE New Mexico region have been investigated, and their stabilities reviewed. Results of these studies have led to the conclusion that cementitious materials can be formulated which are compatible with the major rock types in a bedded salt repository environment. Strengths are more than adequate, permeabilities are consistently very low, and elastic moduli generally increase only very slightly with time. Seal formulation guidelines and recommendations for present and future work are presented. 73 references, 25 figures, 61 tables

  18. Survey and analysis of materials research and development at selected federal laboratories

    Energy Technology Data Exchange (ETDEWEB)

    Reed, J.E.; Fink, C.R.

    1984-04-01

    This document presents the results of an effort to transfer existing, but relatively unknown, materials R and D from selected federal laboratories to industry. More specifically, recent materials-related work at seven federal laboratories potentially applicable to improving process energy efficiency and overall productiviy in six energy-intensive manufacturing industries was evaluated, catalogued, and distributed to industry representatives to gauge their reaction. Laboratories surveyed include: Air Force Wright Aeronautical Laboratories Material Laboratory (AFWAL). Pacific Northwest Laboratory (PNL), National Aeronautics and Space Administration Marshall Flight Center (NASA Marshall), Oak Ridge National Laboratory (ORNL), Brookhaven National Laboratory (BNL), Idaho National Engineering Laboratory (INEL), and Jet Propulsion Laboratory (JPL). Industries included in the effort are: aluminum, cement, paper and allied products, petroleum, steel and textiles.

  19. Caracterización de propóleos provenientes del municipio de Caldas obtenido por dos métodos de recolección

    Directory of Open Access Journals (Sweden)

    Julián Martínez G.

    2012-04-01

    Full Text Available Objetivo. Determinar las características fisicoquímicas y la actividad antimicrobiana de propóleos de Apis mellifera, provenientes del municipio de Caldas, obtenidos por dos métodos de recolección. Materiales y métodos. Se utilizaron dos métodos de recolección: de raspado y trampa plastica. Se estableció el contenido de cera, ceniza, material insoluble y resina de los propóleos crudos. Al extracto etanólico de los propóleos se les determinó el perfil cromatográfico (GC-MS y el espectro UV; además, se evaluó la actividad antimicrobiana in vitro frente a hongos (Aspergillus sp., Penicillium sp., Colletotrichum acutatum y C. gloesporioides, y bacterias (Salmonella tiphy, Bacillus subtilis, Staphylococcus aureus y Escherichia coli. Resultados. El material obtenido mediante malla matrizada presentó un perfil químico amplio, buena actividad antimicrobiana y mejores parámetros de calidad, de acuerdo con estándares establecidos por normas internacionales que los propóleos obtenidos por el método de raspado. Además, pudo observarse que la acción antimicrobiana de los propóleos fue dependiente de la concentración del extracto y del hongo o bacteria evaluada. Conclusiones. La composición química y la actividad antibacteriana y antifúngica de los propóleos están relacionadas con el método de recolección. El presente estudio aporta información para la selección de la técnica de cosecha del propóleo de acuerdo con la aplicación que se desee dar.

  20. LEARNING MATERIALS SELECTION FOR DIFFERENTIATED INSTRUCTION OF ENGLISH FOR SPECIFIC PURPOSES OF FUTURE PROFESSIONALS IN THE FIELD OF INFORMATION TECHNOLOGY

    Directory of Open Access Journals (Sweden)

    Oksana Synekop

    2017-09-01

    Full Text Available In conditions of differentiation the learning materials selection will optimize the training English for Specific Purposes of the future professionals in the field of information technology at university level. The purpose of the article is to define the basic unit of learning material, the factors of influence on the learning material selection, principles, criteria and the procedure of learning material selection in this paper. Reviewing the scientific achievements in the learning material selection in teaching English has become a basis for defining the factors of influence, principles and criteria in the research. The basic unit of learning material (learning English text for professional purposes is outlined. The factors of influence and principles (correspondence of learning materials to professional interests and needs of information technology students; necessary ability and accessibility; regarding the linguistic and stylistic necessity and sufficiency; availability of Internet sources information of the learning material selection are defined. Also, the qualitative criteria (authenticity; professional significance, relevance and informativeness; conformity of foreign language level and intellectual development of students; variety of genres and forms of speech, their sufficient filling by linguistic material; coherence, integrity, consistency, semantic completeness; topic conformity; situation conformity; unlimited access, reliability and exemplarity of Internet sources and the quantitative criteria (the amount of material of the learning material selection are highlighted. The process of English for Specific Purposes material selection (defining the disciplines of different cycles; defining spheres and related topics; outlining situations, communicative roles and intentions of professional communication; specifying the sources of selection; evaluating the texts; analysis of the knowledge, skills and sub-skills required for the

  1. Reexamination of the source material of acid igneous rocks, based on the selected Sr isotopic data

    International Nuclear Information System (INIS)

    Kagami, Hiroo; Shuto, Kenji; Gorai, Masao

    1975-01-01

    The relation between the ages and the initial strontium isotopic compositions obtained from acid igneous rocks by the whole-rock isochron method is re-examined, on the basis of the selected data. The points based on the data having high values of standard deviation (on the isochrons) show considerable scattering. This is probably ascribed to admixture of sialic materials, or secondary alteration and other geologic causes. The points based on the data having lower values of standard deviation (sigma value: 0.0001 - 0.0019), on the other hand, are evidently plotted within a narrow region just above the presumed Sr evolutional region of the source material of oceanic tholeiites. It is noteworthy that the former region meets the latter region at an earlier stage of the evolutional history of the earth (about 40 x 10 8 yrs. ago or older). It may be conceivable that the former region is the Sr evolutional region of the source material of acid igneous rocks. Considering from the inclination of the above Sr evolutional region, the source material of most of acid igneous rocks may possibly be a certain basic material, chemically similar to the continental tholeiitic basalts or basaltic andesites. On the other hand, the source material of a few acid igneous rocks with low initial strontium isotopic ratios may be a certain basic material resembling the oceanic tholeiites. Another possibility is that these acid igneous rocks and oceanic tholeiites may have been formed, under different physical conditions, directly from a certain common source material presumably of peridotitic composition. (auth.)

  2. LEO P: AN UNQUENCHED VERY LOW-MASS GALAXY

    International Nuclear Information System (INIS)

    McQuinn, Kristen B. W.; Skillman, Evan D.; Berg, Danielle; Dolphin, Andrew; Cannon, John M.; Salzer, John J.; Rhode, Katherine L.; Adams, Elizabeth A. K.; Giovanelli, Riccardo; Haynes, Martha P.; Girardi, Léo

    2015-01-01

    Leo P is a low-luminosity dwarf galaxy discovered through the blind H i Arecibo Legacy Fast ALFA survey. The H i and follow-up optical observations have shown that Leo P is a gas-rich dwarf galaxy with active star formation, an underlying older population, and an extremely low oxygen abundance. We have obtained optical imaging with the Hubble Space Telescope to two magnitudes below the red clump in order to study the evolution of Leo P. We refine the distance measurement to Leo P to be 1.62 ± 0.15 Mpc, based on the luminosity of the horizontal branch stars and 10 newly identified RR Lyrae candidates. This places the galaxy at the edge of the Local Group, ∼0.4 Mpc from Sextans B, the nearest galaxy in the NGC 3109 association of dwarf galaxies of which Leo P is clearly a member. The star responsible for ionizing the H ii region is most likely an O7V or O8V spectral type, with a stellar mass ≳25 M ⊙ . The presence of this star provides observational evidence that massive stars at the upper end of the initial mass function are capable of being formed at star formation rates as low as ∼10 −5 M ⊙ yr −1 . The best-fitting star formation history (SFH) derived from the resolved stellar populations of Leo P using the latest PARSEC models shows a relatively constant star formation rate over the lifetime of the galaxy. The modeled luminosity characteristics of Leo P at early times are consistent with low-luminosity dSph Milky Way satellites, suggesting that Leo P is what a low-mass dSph would look like if it evolved in isolation and retained its gas. Despite the very low mass of Leo P, the imprint of reionization on its SFH is subtle at best, and consistent with being totally negligible. The isolation of Leo P, and the total quenching of star formation of Milky Way satellites of similar mass, implies that the local environment dominates the quenching of the Milky Way satellites

  3. LEO P: AN UNQUENCHED VERY LOW-MASS GALAXY

    Energy Technology Data Exchange (ETDEWEB)

    McQuinn, Kristen B. W.; Skillman, Evan D.; Berg, Danielle [Minnesota Institute for Astrophysics, School of Physics and Astronomy, 116 Church Street, S.E., University of Minnesota, Minneapolis, MN 55455 (United States); Dolphin, Andrew [Raytheon Company, 1151 E. Hermans Road, Tucson, AZ 85756 (United States); Cannon, John M. [Department of Physics and Astronomy, Macalester College, 1600 Grand Avenue, Saint Paul, MN 55105 (United States); Salzer, John J.; Rhode, Katherine L. [Department of Astronomy, Indiana University, 727 East 3rd Street, Bloomington, IN 47405 (United States); Adams, Elizabeth A. K. [ASTRON, the Netherlands Institute for Radio Astronomy, Postbus 2, 7990 AA, Dwingeloo (Netherlands); Giovanelli, Riccardo; Haynes, Martha P. [Center for Radiophysics and Space Research, Space Sciences Building, Cornell University, Ithaca, NY 14853 (United States); Girardi, Léo, E-mail: kmcquinn@astro.umn.edu [Osservatorio Astronomico di Padova, INAF, Vicolo dell’Osservatorio 5, I-35122 Padova (Italy)

    2015-10-20

    Leo P is a low-luminosity dwarf galaxy discovered through the blind H i Arecibo Legacy Fast ALFA survey. The H i and follow-up optical observations have shown that Leo P is a gas-rich dwarf galaxy with active star formation, an underlying older population, and an extremely low oxygen abundance. We have obtained optical imaging with the Hubble Space Telescope to two magnitudes below the red clump in order to study the evolution of Leo P. We refine the distance measurement to Leo P to be 1.62 ± 0.15 Mpc, based on the luminosity of the horizontal branch stars and 10 newly identified RR Lyrae candidates. This places the galaxy at the edge of the Local Group, ∼0.4 Mpc from Sextans B, the nearest galaxy in the NGC 3109 association of dwarf galaxies of which Leo P is clearly a member. The star responsible for ionizing the H ii region is most likely an O7V or O8V spectral type, with a stellar mass ≳25 M{sub ⊙}. The presence of this star provides observational evidence that massive stars at the upper end of the initial mass function are capable of being formed at star formation rates as low as ∼10{sup −5} M{sub ⊙} yr{sup −1}. The best-fitting star formation history (SFH) derived from the resolved stellar populations of Leo P using the latest PARSEC models shows a relatively constant star formation rate over the lifetime of the galaxy. The modeled luminosity characteristics of Leo P at early times are consistent with low-luminosity dSph Milky Way satellites, suggesting that Leo P is what a low-mass dSph would look like if it evolved in isolation and retained its gas. Despite the very low mass of Leo P, the imprint of reionization on its SFH is subtle at best, and consistent with being totally negligible. The isolation of Leo P, and the total quenching of star formation of Milky Way satellites of similar mass, implies that the local environment dominates the quenching of the Milky Way satellites.

  4. Bowtie filters for dedicated breast CT: Analysis of bowtie filter material selection

    Energy Technology Data Exchange (ETDEWEB)

    Kontson, Kimberly, E-mail: Kimberly.Kontson@fda.hhs.gov; Jennings, Robert J. [Department of Bioengineering, University of Maryland, College Park, Maryland 20742 and Division of Imaging and Applied Mathematics, Office of Science and Engineering Laboratories, Center for Devices and Radiological Health, U.S. Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, Maryland 20993 (United States)

    2015-09-15

    Purpose: For a given bowtie filter design, both the selection of material and the physical design control the energy fluence, and consequently the dose distribution, in the object. Using three previously described bowtie filter designs, the goal of this work is to demonstrate the effect that different materials have on the bowtie filter performance measures. Methods: Three bowtie filter designs that compensate for one or more aspects of the beam-modifying effects due to the differences in path length in a projection have been designed. The nature of the designs allows for their realization using a variety of materials. The designs were based on a phantom, 14 cm in diameter, composed of 40% fibroglandular and 60% adipose tissue. Bowtie design #1 is based on single material spectral matching and produces nearly uniform spectral shape for radiation incident upon the detector. Bowtie design #2 uses the idea of basis-material decomposition to produce the same spectral shape and intensity at the detector, using two different materials. With bowtie design #3, it is possible to eliminate the beam hardening effect in the reconstructed image by adjusting the bowtie filter thickness so that the effective attenuation coefficient for every ray is the same. Seven different materials were chosen to represent a range of chemical compositions and densities. After calculation of construction parameters for each bowtie filter design, a bowtie filter was created using each of these materials (assuming reasonable construction parameters were obtained), resulting in a total of 26 bowtie filters modeled analytically and in the PENELOPE Monte Carlo simulation environment. Using the analytical model of each bowtie filter, design profiles were obtained and energy fluence as a function of fan-angle was calculated. Projection images with and without each bowtie filter design were also generated using PENELOPE and reconstructed using FBP. Parameters such as dose distribution, noise uniformity

  5. Bowtie filters for dedicated breast CT: Analysis of bowtie filter material selection

    International Nuclear Information System (INIS)

    Kontson, Kimberly; Jennings, Robert J.

    2015-01-01

    Purpose: For a given bowtie filter design, both the selection of material and the physical design control the energy fluence, and consequently the dose distribution, in the object. Using three previously described bowtie filter designs, the goal of this work is to demonstrate the effect that different materials have on the bowtie filter performance measures. Methods: Three bowtie filter designs that compensate for one or more aspects of the beam-modifying effects due to the differences in path length in a projection have been designed. The nature of the designs allows for their realization using a variety of materials. The designs were based on a phantom, 14 cm in diameter, composed of 40% fibroglandular and 60% adipose tissue. Bowtie design #1 is based on single material spectral matching and produces nearly uniform spectral shape for radiation incident upon the detector. Bowtie design #2 uses the idea of basis-material decomposition to produce the same spectral shape and intensity at the detector, using two different materials. With bowtie design #3, it is possible to eliminate the beam hardening effect in the reconstructed image by adjusting the bowtie filter thickness so that the effective attenuation coefficient for every ray is the same. Seven different materials were chosen to represent a range of chemical compositions and densities. After calculation of construction parameters for each bowtie filter design, a bowtie filter was created using each of these materials (assuming reasonable construction parameters were obtained), resulting in a total of 26 bowtie filters modeled analytically and in the PENELOPE Monte Carlo simulation environment. Using the analytical model of each bowtie filter, design profiles were obtained and energy fluence as a function of fan-angle was calculated. Projection images with and without each bowtie filter design were also generated using PENELOPE and reconstructed using FBP. Parameters such as dose distribution, noise uniformity

  6. Ultrahigh and Selective SO2 Uptake in Inorganic Anion-Pillared Hybrid Porous Materials.

    Science.gov (United States)

    Cui, Xili; Yang, Qiwei; Yang, Lifeng; Krishna, Rajamani; Zhang, Zhiguo; Bao, Zongbi; Wu, Hui; Ren, Qilong; Zhou, Wei; Chen, Banglin; Xing, Huabin

    2017-07-01

    The efficient capture of SO 2 is of great significance in gas-purification processes including flue-gas desulfurization and natural-gas purification, but the design of porous materials with high adsorption capacity and selectivity of SO 2 remains very challenging. Herein, the selective recognition and dense packing of SO 2 clusters through multiple synergistic host-guest and guest-guest interactions by controlling the pore chemistry and size in inorganic anion (SiF 6 2- , SIFSIX) pillared metal-organic frameworks is reported. The binding sites of anions and aromatic rings in SIFSIX materials grasp every atom of SO 2 firmly via S δ+ ···F δ- electrostatic interactions and O δ- ···H δ+ dipole-dipole interactions, while the guest-guest interactions between SO 2 molecules further promote gas trapping within the pore space, which is elucidated by first-principles density functional theory calculations and powder X-ray diffraction experiments. These interactions afford new benchmarks for the highly efficient removal of SO 2 from other gases, even if at a very low SO 2 concentration. Exceptionally high SO 2 capacity of 11.01 mmol g -1 is achieved at atmosphere pressure by SIFSIX-1-Cu, and unprecedented low-pressure SO 2 capacity is obtained in SIFSIX-2-Cu-i (4.16 mmol g -1 SO 2 at 0.01 bar and 2.31 mmol g -1 at 0.002 bar). More importantly, record SO 2 /CO 2 selectivity (86-89) and excellent SO 2 /N 2 selectivity (1285-3145) are also achieved. Experimental breakthrough curves further demonstrate the excellent performance of these hybrid porous materials in removing low-concentration SO 2 . © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Concept selection of car bumper beam with developed hybrid bio-composite material

    International Nuclear Information System (INIS)

    Davoodi, M.M.; Sapuan, S.M.; Ahmad, D.; Aidy, A.; Khalina, A.; Jonoobi, Mehdi

    2011-01-01

    Highlights: → We simulate the low impact test by Abaqus Ver16R9 using the same material model. → Six different weighted criteria were discussed to nominate the best concept. → Double Hat Profile showed the best concept to fulfil the defined PDS. → Geometric parameters may overcome the weak inherent properties of bio composite. → Toughened bio-composite material may employ in structural automotive components. -- Abstract: Application of natural fibre composites is going to increase in different areas caused by environmental, technical and economic advantages. However, their low mechanical properties have limited their particular application in automotive structural components. Hybridizations with other reinforcements or matrices can improve mechanical properties of natural fibre composite. Moreover, geometric optimizations have a significant role in structural strength improvement. This study focused on selecting the best geometrical bumper beam concept to fulfill the safety parameters of the defined product design specification (PDS). The mechanical properties of developed hybrid composite material were considered in different bumper beam concepts with the same frontal curvature, thickness, and overall dimensions. The low-speed impact test was simulated under the same conditions in Abaqus V16R9 software. Six weighted criteria, which were deflection, strain energy, mass, cost, easy manufacturing, and the rib possibility were analyzed to form an evaluation matrix. Topsis method was employed to select the best concept. It is concluded that double hat profile (DHP) with defined material model can be used for bumper beam of a small car. In addition, selected concept can be strengthened by adding reinforced ribs or increasing the thickness of the bumper beam to comply with the defined PDS.

  8. Standard Guide for Selection of Test Methods for Interlayer Materials for Aerospace Transparent Enclosures

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2002-01-01

    1.1 This guide summarizes the standard test methods available for determining physical and mechanical characteristics of interlayer materials used in multi-ply aerospace transparent enclosures. 1.2 Interlayer materials are used to laminate glass-to-glass, glass-to-plastic, and plastic-to-plastic. Interlayer materials are basically transparent adhesives with high-quality optical properties. They can also serve as an energy absorbing medium, a fail-safe membrane to contain cockpit pressure and to prevent entry of impact debris; a strain insulator to accommodate different thermal expansion rates of members being laminated and as an adherent to prevent spalling of inner surface ply material fragments. The relative importance of an interlayer characteristic will be a function of the prime use it serves in its particular application. 1.3 This guide, as a summary of various methods in Section 2, is intended to facilitate the selection of tests that can be applied to interlayer materials. 1.4 The test methods list...

  9. Reduced Graphene Oxide-Gold Nanoparticle Nanoframework as a Highly Selective Separation Material for Aflatoxins.

    Science.gov (United States)

    Guo, Wenbo; Wu, Lidong; Fan, Kai; Nie, Dongxia; He, Weijing; Yang, Junhua; Zhao, Zhihui; Han, Zheng

    2017-11-03

    Graphene-based materials have been studied in many applications, owing to the excellent electrical, mechanical, and thermal properties of graphene. In the current study, an environmentally friendly approach to the preparation of a reduced graphene oxide-gold nanoparticle (rGO-AuNP) nanocomposite was developed by using L-cysteine and vitamin C as reductants under mild reaction conditions. The rGO-AuNP material showed a highly selective separation ability for 6 naturally occurring aflatoxins, which are easily adsorbed onto traditional graphene materials but are difficult to be desorbed. The specificity of the nanocomposite was evaluated in the separation of 6 aflatoxin congeners (aflatoxin B1, aflatoxin B2, aflatoxin G1, aflatoxin G2, aflatoxin M1 and aflatoxin M2) from 23 other biotoxins (including, ochratoxin A, citrinin, and deoxynivalenol). The results indicated that this material was specific for separating aflatoxin congeners. The synthesized material was further validated by determining the recovery (77.6-105.0%), sensitivity (limit of detection in the range of 0.05-0.21 μg kg -1 ), and precision (1.5-11.8%), and was then successfully applied to the separation of aflatoxins from real-world maize, wheat and rice samples.

  10. Sustainable manufacturing: Effect of material selection and design on the environmental impact in the manufacturing process

    International Nuclear Information System (INIS)

    Harun, Mohd Hazwan Syafiq; Salaam, Hadi Abdul; Taha, Zahari

    2013-01-01

    The environmental impact of a manufacturing process is also dependent on the selection of the material and design of a product. This is because the manufacturing of a product is directly connected to the amount of carbon emitted in consuming the electrical energy for that manufacturing process. The difference in the general properties of materials such as strength, hardness and impact will have significant effect on the power consumption of the machine used to complete the product. In addition the environmental impact can also be reduced if the proposed designs use less material. In this study, an LCA tool called Eco-It is used. Evaluate the environmental impact caused by manufacturing simple jig. A simple jig with 4 parts was used as a case study. Two experiments were carried out. The first experiment was to study the environmental effects of different material, and the second experiment was to study the environmental impact of different design. The materials used for the jig are Aluminium and mild steel. The results showed a decrease in the rate of carbon emissions by 60% when Aluminium is use instead from mild steel, and a decrease of 26% when the-design is modified

  11. Dual-Material Electron Beam Selective Melting: Hardware Development and Validation Studies

    Directory of Open Access Journals (Sweden)

    Chao Guo

    2015-03-01

    Full Text Available Electron beam selective melting (EBSM is an additive manufacturing technique that directly fabricates three-dimensional parts in a layerwise fashion by using an electron beam to scan and melt metal powder. In recent years, EBSM has been successfully used in the additive manufacturing of a variety of materials. Previous research focused on the EBSM process of a single material. In this study, a novel EBSM process capable of building a gradient structure with dual metal materials was developed, and a powder-supplying method based on vibration was put forward. Two different powders can be supplied individually and then mixed. Two materials were used in this study: Ti6Al4V powder and Ti47Al2Cr2Nb powder. Ti6Al4V has excellent strength and plasticity at room temperature, while Ti47Al2Cr2Nb has excellent performance at high temperature, but is very brittle. A Ti6Al4V/Ti47Al2Cr2Nb gradient material was successfully fabricated by the developed system. The microstructures and chemical compositions were characterized by optical microscopy, scanning microscopy, and electron microprobe analysis. Results showed that the interface thickness was about 300 μm. The interface was free of cracks, and the chemical compositions exhibited a staircase-like change within the interface.

  12. Selection Criteria and Methods for Testing Different Surface Materials for Contact Frying Processes

    DEFF Research Database (Denmark)

    Ashokkumar, Saranya

    Inner surfaces of industrial process equipment for food are often coated to give the surfaces particular properties with respect to adhesion and cleanability. Existing coating materials (PTFE (Teflon®) or silicone based polymers) suffer from drawbacks when used in contact frying, because these co...... surface materials for contact frying processes. The surfaces selected for this purpose cover a wide spectrum of materials that range from hydrophobic to hydrophilic materials. The different surface materials investigated include stainless steel (reference), aluminium (Al Mg 5754), PTFE......, an experimental rig has been constructed which enabled a controlled fouling of different coatings on steel and aluminium substrates under realistic frying conditions. A subjective rating procedure was employed for screening different surfaces according to their non-stick properties when used for frying of a model...... defects and surface roughness play a significant role. The wear resistance of the coatings was tested by performing abrasive wear experiments. The ceramic coatings: TiAlN and ZrN were found to show the best wear resistance properties. The experiments also revealed the poor wear resistance of stainless...

  13. Piezoelectric materials selection for sensor applications using finite element and multiple attribute decision-making approaches

    Directory of Open Access Journals (Sweden)

    Anuruddh Kumar

    2015-03-01

    Full Text Available This paper examines the selection and performance evaluation of a variety of piezoelectric materials for cantilever-based sensor applications. The finite element analysis method is implemented to evaluate the relative importance of materials properties such as Young's Modulus (E, piezoelectric stress constants (e31, dielectric constant (ε and Poisson's ratio (υ for cantilever-based sensor applications. An analytic hierarchy process (AHP is used to assign weights to the properties that are studied for the sensor structure under study. A technique for order preference by similarity to ideal solution (TOPSIS is used to rank the performance of the piezoelectric materials in the context of sensor voltage outputs. The ranking achieved by the TOPSIS analysis is in good agreement with the results obtained from finite element method simulation. The numerical simulations show that K0.5Na0.5NbO3–LiSbO3 (KNN–LS materials family is important for sensor application. Young's modulus (E is most influencing material's property followed by piezoelectric constant (e31, dielectric constant (ε and Poisson's ratio (υ for cantilever-based piezoelectric sensor applications.

  14. Cost-driven materials selection criteria for redox flow battery electrolytes

    Science.gov (United States)

    Dmello, Rylan; Milshtein, Jarrod D.; Brushett, Fikile R.; Smith, Kyle C.

    2016-10-01

    Redox flow batteries show promise for grid-scale energy storage applications but are presently too expensive for widespread adoption. Electrolyte material costs constitute a sizeable fraction of the redox flow battery price. As such, this work develops a techno-economic model for redox flow batteries that accounts for redox-active material, salt, and solvent contributions to the electrolyte cost. Benchmark values for electrolyte constituent costs guide identification of design constraints. Nonaqueous battery design is sensitive to all electrolyte component costs, cell voltage, and area-specific resistance. Design challenges for nonaqueous batteries include minimizing salt content and dropping redox-active species concentration requirements. Aqueous battery design is sensitive to only redox-active material cost and cell voltage, due to low area-specific resistance and supporting electrolyte costs. Increasing cell voltage and decreasing redox-active material cost present major materials selection challenges for aqueous batteries. This work minimizes cost-constraining variables by mapping the battery design space with the techno-economic model, through which we highlight pathways towards low price and moderate concentration. Furthermore, the techno-economic model calculates quantitative iterations of battery designs to achieve the Department of Energy battery price target of 100 per kWh and highlights cost cutting strategies to drive battery prices down further.

  15. Stock selection of high-dose-irradiation-resistant materials for filter press under high-dose irradiation operation

    International Nuclear Information System (INIS)

    Ishiyama, Shintaro; Minami, Mamoru; Hara, Kouji; Yamashita, Manabu

    2015-01-01

    In a volume reduction process for the decontamination of contained soil, the performance degradation of a filter press is expected owing to material deterioration under high-dose irradiation. Eleven-stock selection of candidate materials including polymers, fibers and rubbers for the filter press was conducted to achieve a high performance of volume reduction of contaminated soil and the following results were derived. Crude rubber and nylon were selected as prime candidates for packing, diaphragm and filter plate materials. Polyethylene was also selected as a prime candidate for the filter cloth material. (author)

  16. Screening tests for hazard classification of complex waste materialsSelection of methods

    International Nuclear Information System (INIS)

    Weltens, R.; Vanermen, G.; Tirez, K.; Robbens, J.; Deprez, K.; Michiels, L.

    2012-01-01

    In this study we describe the development of an alternative methodology for hazard characterization of waste materials. Such an alternative methodology for hazard assessment of complex waste materials is urgently needed, because the lack of a validated instrument leads to arbitrary hazard classification of such complex waste materials. False classification can lead to human and environmental health risks and also has important financial consequences for the waste owner. The Hazardous Waste Directive (HWD) describes the methodology for hazard classification of waste materials. For mirror entries the HWD classification is based upon the hazardous properties (H1–15) of the waste which can be assessed from the hazardous properties of individual identified waste compounds or – if not all compounds are identified – from test results of hazard assessment tests performed on the waste material itself. For the latter the HWD recommends toxicity tests that were initially designed for risk assessment of chemicals in consumer products (pharmaceuticals, cosmetics, biocides, food, etc.). These tests (often using mammals) are not designed nor suitable for the hazard characterization of waste materials. With the present study we want to contribute to the development of an alternative and transparent test strategy for hazard assessment of complex wastes that is in line with the HWD principles for waste classification. It is necessary to cope with this important shortcoming in hazardous waste classification and to demonstrate that alternative methods are available that can be used for hazard assessment of waste materials. Next, by describing the pros and cons of the available methods, and by identifying the needs for additional or further development of test methods, we hope to stimulate research efforts and development in this direction. In this paper we describe promising techniques and argument on the test selection for the pilot study that we have performed on different

  17. New sorbent materials for selective extraction of cocaine and benzoylecgonine from human urine samples.

    Science.gov (United States)

    Bujak, Renata; Gadzała-Kopciuch, Renata; Nowaczyk, Alicja; Raczak-Gutknecht, Joanna; Kordalewska, Marta; Struck-Lewicka, Wiktoria; Waszczuk-Jankowska, Małgorzata; Tomczak, Ewa; Kaliszan, Michał; Buszewski, Bogusław; Markuszewski, Michał J

    2016-02-20

    An increase in cocaine consumption has been observed in Europe during the last decade. Benzoylecgonine, as a main urinary metabolite of cocaine in human, is so far the most reliable marker of cocaine consumption. Determination of cocaine and its metabolite in complex biological samples as urine or blood, requires efficient and selective sample pretreatment. In this preliminary study, the newly synthesized sorbent materials were proposed for selective extraction of cocaine and benzoylecgonine from urine samples. Application of these sorbent media allowed to determine cocaine and benzoylecgonine in urine samples at the concentration level of 100ng/ml with good recovery values as 81.7%±6.6 and 73.8%±4.2, respectively. The newly synthesized materials provided efficient, inexpensive and selective extraction of both cocaine and benzoylecgonine from urine samples, which can consequently lead to an increase of the sensitivity of the current available screening diagnostic tests. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Scarab/Saffron Development Project Case study: Material Selection Criteria for the Monoethylene Glycol Recovery Package

    International Nuclear Information System (INIS)

    Moussa, A.M.; Habib, S.; Shinaishin, A.

    2004-01-01

    MEG Recovery Unit for Scarab/Saffron development project is the first application in gas production. The Mono Ethylene Glycol Recovery Unit (MEG) recovers MEG from Water/MEG stream and removes salts and other contaminants. MEG Recovery Unit Equipment Design Criteria were designed for two parallel trains A and B, each train is capable to treat 500 bbl MEG, 1500 bbl water and 9 ton salt. The MEG unit is a combination of two unit operations; MEG Recovery unit is normally applicable in the oil and gas industries that is applying distillation technique, while the new technology is salt treatment and handling. The MEG Unit material selection is made to be suitable for the entire design life which is 25 years, the materials for MEG Recovery Unit have been selected among the available corrosion resistance alloys, where requested by the service and ambient conditions. Therefore all. the parts of the MEG unit that are in saline service are in either (2205 duplex, AISI 316L) and in Inconel alloy 625 related to operating temperature. This case study focused at Inconel alloy 625, which is selected for salt service and their operation problem occurred during the construction and operating conditions

  19. Effect of the selected seismic energy dissipation capacity on the materials quantity for reinforced concrete walls

    Directory of Open Access Journals (Sweden)

    José Miguel Benjumea Royero

    2017-02-01

    Full Text Available Context: Regarding their design of reinforced concrete structural walls, the Colombian seismic design building code allows the engineer to select one of the three seismic energy dissipation capacity (ordinary, moderate, and special depending on the seismic hazard of the site. Despite this, it is a common practice to choose the minor requirement for the site because it is thought that selecting a higher requirement will lead to larger structural materials amounts and, therefore, cost increments.  Method: In this work, an analytical study was performed in order to determine the effect of the selected energy dissipation capacity on the quantity of materials and ductility displacement capacity of R/C walls. The study was done for a region with low seismic hazard, mainly because this permitted to explore and compare the use of the three seismic energy dissipations capacities. The effect of different parameters such as the wall total height and thickness, the tributary loaded area, and the minimum volumetric steel ratio were studied. Results: The total amount of steel required for the walls with moderate and special energy dissipation capacity corresponds, on average, to 77% and 89%, respectively, of the quantity required for walls with minimum capacity. Conclusions: it is possible to achieve reductions in the total steel required weight when adopting either moderated or special seismic energy dissipation instead of the minimum capacity.  Additionally, a significant increment in the seismic ductility displacements capacity of the wall was obtained.

  20. Phase analysis of nano-phase materials using selected area electron diffraction in the TEM

    International Nuclear Information System (INIS)

    Labar, J. L.

    2002-01-01

    In analogy to X-ray power diffraction (XRD), we are developing a method to help phase identification when examining a large number of grains simultaneously by electron diffraction. Although XRD is well established, it can not be used for small quantities of materials (volumes below 1 mm 3 ). Examining a usual TEM sample with thickness of 100 nm and using a selected area of 1 mm in diameter, the selected area electron diffraction pattern (SAED) carries information about several thousands of grains from a material with an average grain size of about 10 nm. The accuracy of XRD can not be attained by electron diffraction (ED). However, simultaneous visual observation of the nanostructure is an additional benefit of TEM (beside the small amount of needed material). The first step of the development project was the development of a computer program ('ProcessDiffraction') that processes digital versions of SAED patterns and presents them in an XRD-like form (intensity vs. scattering vector). In the present version (V2.0.3) phase identification is carried out by comparing the measured distribution to 'Markers', i.e. data of known phases. XRD data cards are used if the detailed structure of a phase is not known. Kinematic electron diffraction intensities are calculated for phases with known atomic positions (Author)

  1. A materials selection procedure for sandwiched beams via parametric optimization with applications in automotive industry

    International Nuclear Information System (INIS)

    Aly, Mohamed F.; Hamza, Karim T.; Farag, Mahmoud M.

    2014-01-01

    Highlights: • Sandwich panels optimization model. • Sandwich panels design procedure. • Study of sandwich panels for automotive vehicle flooring. • Study of sandwich panels for truck cabin exterior. - Abstract: The future of automotive industry faces many challenges in meeting increasingly strict restrictions on emissions, energy usage and recyclability of components alongside the need to maintain cost competiveness. Weight reduction through innovative design of components and proper material selection can have profound impact towards attaining such goals since most of the lifecycle energy usage occurs during the operation phase of a vehicle. In electric and hybrid vehicles, weight reduction has another important effect of extending the electric mode driving range between stops or gasoline mode. This paper adopts parametric models for design optimization and material selection of sandwich panels with the objective of weight and cost minimization subject to structural integrity constraints such as strength, stiffness and buckling resistance. The proposed design procedure employs a pre-compiled library of candidate sandwich panel material combinations, for which optimization of the layered thicknesses is conducted and the best one is reported. Example demonstration studies from the automotive industry are presented for the replacement of Aluminum and Steel panels with polypropylene-filled sandwich panel alternatives

  2. Exponential growth and selection in self-replicating materials from DNA origami rafts

    Science.gov (United States)

    He, Xiaojin; Sha, Ruojie; Zhuo, Rebecca; Mi, Yongli; Chaikin, Paul M.; Seeman, Nadrian C.

    2017-10-01

    Self-replication and evolution under selective pressure are inherent phenomena in life, and but few artificial systems exhibit these phenomena. We have designed a system of DNA origami rafts that exponentially replicates a seed pattern, doubling the copies in each diurnal-like cycle of temperature and ultraviolet illumination, producing more than 7 million copies in 24 cycles. We demonstrate environmental selection in growing populations by incorporating pH-sensitive binding in two subpopulations. In one species, pH-sensitive triplex DNA bonds enable parent-daughter templating, while in the second species, triplex binding inhibits the formation of duplex DNA templating. At pH 5.3, the replication rate of species I is ~1.3-1.4 times faster than that of species II. At pH 7.8, the replication rates are reversed. When mixed together in the same vial, the progeny of species I replicate preferentially at pH 7.8 similarly at pH 5.3, the progeny of species II take over the system. This addressable selectivity should be adaptable to the selection and evolution of multi-component self-replicating materials in the nanoscopic-to-microscopic size range.

  3. Gadolinium(III) ion selective sensor using a new synthesized Schiff's base as a sensing material

    International Nuclear Information System (INIS)

    Zamani, Hassan Ali; Mohammadhosseini, Majid; Haji-Mohammadrezazadeh, Saeed; Faridbod, Farnoush; Ganjali, Mohammad Reza; Meghdadi, Soraia; Davoodnia, Abolghasem

    2012-01-01

    According to a solution study which showed a selective complexation between N,N′-bis(methylsalicylidene)-2-aminobenzylamine (MSAB) and gadolinium ions, MSAB was used as a sensing element in construction of a gadolinium(III) ion selective electrode. Acetophenon (AP) was used as solvent mediator and sodium tetraphenyl borate (NaTPB) as an anion excluder. The electrode showed a good selectivity towards Gd(III) ions over a wide variety of cations tested. The constructed sensor displayed a Nernstian behavior (19.7 ± 0.3 mV/decade) in the concentration range of 1.0 × 10 −6 to 1.0 × 10 −2 mol L −1 with detection limit of 5.0 × 10 −7 mol L −1 and a short response time ( 3+ –PVC membrane sensor based on an ion carrier as sensing material is introduced. ► This technique is very simple and it's not necessary to use sophisticated equipment. ► This sensor shows good selectivity against other metal ions.

  4. Global blending optimization of laminated composites with discrete material candidate selection and thickness variation

    DEFF Research Database (Denmark)

    Sørensen, Søren N.; Stolpe, Mathias

    2015-01-01

    rate. The capabilities of the method and the effect of active versus inactive manufacturing constraints are demonstrated on several numerical examples of limited size, involving at most 320 binary variables. Most examples are solved to guaranteed global optimality and may constitute benchmark examples...... but is, however, convex in the original mixed binary nested form. Convexity is the foremost important property of optimization problems, and the proposed method can guarantee the global or near-global optimal solution; unlike most topology optimization methods. The material selection is limited...... for popular topology optimization methods and heuristics based on solving sequences of non-convex problems. The results will among others demonstrate that the difficulty of the posed problem is highly dependent upon the composition of the constitutive properties of the material candidates....

  5. Selective retention of oils in aqueous mixtures using palygorskite treated with waterproof materials

    International Nuclear Information System (INIS)

    Matesanz, J.M.; Aisa, C.; Aragues, J.L.; Ovelleiro, J.L.

    1994-01-01

    An oil-selective absorbent has been developed from clay materials that is easy to manufacture and use, and provides good results in different working conditions, compared to conventional water treatment methods. The absorbent can be used in fixed beds in a column or spread directly onto an oil spill. The absorbent is a palygorskite (attapulgite) coated with a silicone. The silicone coating reduces the water absorption capacity of the palygorskite to near zero, but affects oil absorption capacity very little. The Westinghouse method was used to evaluate the absorption capacity of the silicone-coated palygorskite. The results indicate that the material could be a good choice for reducing the organic matter content of drinking water. 4 refs., 2 figs., 2 tabs

  6. Mechanical characterization of selected adhesives and bulk materials at liquid nitrogen and room temperatures

    International Nuclear Information System (INIS)

    Fitzpatrick, C.M.; Stoddart, W.C.T.

    1977-01-01

    This paper presents the results of a series of mechanical tests on selected adhesives and bulk materials. The materials tested are of general interest to designers of magnets for cryogenic service and include several epoxies, a varnish, a B-stage glass cloth, insulation papers, and commercially available fiber-reinforced composites. These tests were performed at room temperature (293 K) and at liquid nitrogen temperature (77 K). The tests include both simple tension tests and lap shear tests with various adherends. The parameters critical to tensile or bond strength were varied as part of the test program. The procedures used to manufacture and test these specimens and the results of the tests are reported in this paper

  7. Mimicking heme enzymes in the solid state: metal-organic materials with selectively encapsulated heme.

    Science.gov (United States)

    Larsen, Randy W; Wojtas, Lukasz; Perman, Jason; Musselman, Ronald L; Zaworotko, Michael J; Vetromile, Carissa M

    2011-07-13

    To carry out essential life processes, nature has had to evolve heme enzymes capable of synthesizing and manipulating complex molecules. These proteins perform a plethora of chemical reactions utilizing a single iron porphyrin active site embedded within an evolutionarily designed protein pocket. We herein report the first class of metal-organic materials (MOMs) that mimic heme enzymes in terms of both structure and reactivity. The MOMzyme-1 class is based upon a prototypal MOM, HKUST-1, into which catalytically active metalloporphyrins are selectively encapsulated in a "ship-in-a-bottle" fashion within one of the three nanoscale cages that exist in HKUST-1. MOMs offer unparalleled levels of permanent porosity and their modular nature affords enormous diversity of structures and properties. The MOMzyme-1 class could therefore represent a new paradigm for heme biomimetic catalysis since it combines the activity of a homogeneous catalyst with the stability and recyclability of heterogeneous catalytic systems within a single material.

  8. Selecting the minimum risk route in the transportation of hazardous materials

    Directory of Open Access Journals (Sweden)

    Marijan Žura

    1992-12-01

    Full Text Available The transportation of hazardous materials is a broad and complex topic. Percent and iveight of accidents of vehicles carrying dangerous goods are growing fast. Modern computer based information system for dangerous materials management is becoming more and more important. In this paper I present an interactive software system for minimum risk route selection based on the PC ARC/INFO. The model computes optimal path based on accident probability is computed from traffic accident rates, highway operational speed, traffic volume and technical characteristic of the roadwidth, radius and slope. Dangerous goods are classified into nine classes according to their impact to different sensible environment elements. Those sensible elements are drinking water resourses, natural heritage, forestry, agricultural areas, cultural heritage, urban areas and tourist resorts. Some results of system implementation on Slovenia road network are be presented.

  9. Diffusion, Thermal Properties and Chemical Compatibilities of Select MAX Phases with Materials For Advanced Nuclear Systems

    Energy Technology Data Exchange (ETDEWEB)

    Barsoum, Michel [Drexel Univ., Philadelphia, PA (United States); Bentzel, Grady [Drexel Univ., Philadelphia, PA (United States); Tallman, Darin J. [Drexel Univ., Philadelphia, PA (United States); Sindelar, Robert [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Garcia-Diaz, Brenda [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Hoffman, Elizabeth [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-04-04

    The demands of Gen IV nuclear power plants for long service life under neutron irradiation at high temperature are severe. Advanced materials that would withstand high temperatures (up to 1000+ ºC) to high doses in a neutron field would be ideal for reactor internal structures and would add to the long service life and reliability of the reactors. The objective of this work is to investigate the chemical compatibility of select MAX with potential materials that are important for nuclear energy, as well as to measure the thermal transport properties as a function of neutron irradiation. The chemical counterparts chosen for this work are: pyrolytic carbon, SiC, U, Pd, FLiBe, Pb-Bi and Na, the latter 3 in the molten state. The thermal conductivities and heat capacities of non-irradiated MAX phases will be measured.

  10. Malignant lymphoma in african lions (panthera leo).

    Science.gov (United States)

    Harrison, T M; McKnight, C A; Sikarskie, J G; Kitchell, B E; Garner, M M; Raymond, J T; Fitzgerald, S D; Valli, V E; Agnew, D; Kiupel, M

    2010-09-01

    Malignant lymphoma has become an increasingly recognized problem in African lions (Panthera leo). Eleven African lions (9 male and 2 female) with clinical signs and gross and microscopic lesions of malignant lymphoma were evaluated in this study. All animals were older adults, ranging in age from 14 to 19 years. Immunohistochemically, 10 of the 11 lions had T-cell lymphomas (CD3(+), CD79a(-)), and 1 lion was diagnosed with a B-cell lymphoma (CD3(-), CD79a(+)). The spleen appeared to be the primary site of neoplastic growth in all T-cell lymphomas, with involvement of the liver (6/11) and regional lymph nodes (5/11) also commonly observed. The B-cell lymphoma affected the peripheral lymph nodes, liver, and spleen. According to the current veterinary and human World Health Organization classification of hematopoietic neoplasms, T-cell lymphoma subtypes included peripheral T-cell lymphoma (4/11), precursor (acute) T-cell lymphoblastic lymphoma/leukemia (2/11), chronic T-cell lymphocytic lymphoma/leukemia (3/11), and T-zone lymphoma (1/11). The single B-cell lymphoma subtype was consistent with diffuse large B-cell lymphoma. Feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) testing by immunohistochemistry on sections of malignant lymphoma was negative for all 11 lions. One lion was seropositive for FeLV. In contrast to domestic and exotic cats, in which B-cell lymphomas are more common than T-cell lymphomas, African lions in this study had malignant lymphomas that were primarily of T-cell origin. Neither FeLV nor FIV, important causes of malignant lymphoma in domestic cats, seems to be significant in the pathogenesis of malignant lymphoma in African lions.

  11. Highly selective and stable carbon dioxide uptake in polyindole-derived microporous carbon materials.

    Science.gov (United States)

    Saleh, Muhammad; Tiwari, Jitendra N; Kemp, K Christain; Yousuf, Muhammad; Kim, Kwang S

    2013-05-21

    Adsorption with solid sorbents is considered to be one of the most promising methods for the capture of carbon dioxide (CO₂) from power plant flue gases. In this study, microporous carbon materials used for CO₂ capture were synthesized by the chemical activation of polyindole nanofibers (PIF) at temperatures from 500 to 800 °C using KOH, which resulted in nitrogen (N)-doped carbon materials. The N-doped carbon materials were found to be microporous with an optimal adsorption pore size for CO₂ of 0.6 nm and a maximum (Brunauer-Emmett-Teller) BET surface area of 1185 m(2) g(-1). The PIF activated at 600 °C (PIF6) has a surface area of 527 m(2) g(-1) and a maximum CO₂ storage capacity of 3.2 mmol g(-1) at 25 °C and 1 bar. This high CO₂ uptake is attributed to its highly microporous character and optimum N content. Additionally, PIF6 material displays a high CO₂ uptake at low pressure (1.81 mmol g(-1) at 0.2 bar and 25 °C), which is the best low pressure CO₂ uptake reported for carbon-based materials. The adsorption capacity of this material remained remarkably stable even after 10 cycles. The isosteric heat of adsorption was calculated to be in the range of 42.7-24.1 kJ mol(-1). Besides the excellent CO₂ uptake and stability, PIF6 also exhibits high selectivity values for CO₂ over N₂, CH₄, and H₂ of 58.9, 12.3, and 101.1 at 25 °C, respectively, and these values are significantly higher than reported values.

  12. Biomimicry in Product Design through Materials Selection and Computer Aided Engineering

    Science.gov (United States)

    Alexandridis, G.; Tzetzis, D.; Kyratsis, P.

    2016-11-01

    The aim of this study is to demonstrate a 7-step methodology that describes the way nature can act as a source of inspiration for the design and the development of a product. Furthermore, it suggests special computerized tools and methods for the product optimization regarding its environmental impact i.e. material selection, production methods. For validation purposes, a garden chaise lounge that imitates the form of a scorpion was developed as a result for the case study and the presentation of the current methodology.

  13. Material Deprivation in Selected EU Countries According to EU-SILC Income Statistics

    Directory of Open Access Journals (Sweden)

    Stávková Jana

    2012-06-01

    Full Text Available The article deals with issues of households at risk of poverty in relative conception. Income poverty means a situation when the threshold of 0.6 of median income is not achieved. The analysis of a broader definition of poverty is based on identification and assessment of material deprivation factors, including: financial stress, housing conditions, availability of consumer durables and basic needs. Data sources are based EU-SILC dataset. Presented analysis is focused on selected EU countries, namely Czech Republic, Finland, France, Spain and United Kingdom. The result identifies the problem areas that cause deprivation symptoms.

  14. Mould Design and Material selection for Film Insert Moulding of Direct Methanol Fuel Cell Packaging

    DEFF Research Database (Denmark)

    Wöhner, Timo; Senkbeil, S.; Olesen, T. L.

    2015-01-01

    This paper presents the mould design for an injection moulding (IM) process for the production of a methanol container for the use in small, passive Direct Methanol Fuel Cell (DMFC) systems, which are intended to be used in behind-the-ear hearing aid systems. One of the crucial properties...... for the production of containers with different venting area and location of the venting holes and the use of different membrane thicknesses by using the same mould. Mould design and material selection are presented....

  15. Selection of flowing liquid lead target structural materials for accelerator driven transmutation applications

    International Nuclear Information System (INIS)

    Park, J.J.; Buksa, J.J.

    1994-01-01

    The beam entry window and container for a liquid lead spallation target will be exposed to high fluxes of protons and neutrons that are both higher in magnitude and energy than have been experienced in proton accelerators and fission reactors, as well as in a corrosive environment. The structural material of the target should have a good compatibility with liquid lead, a sufficient mechanical strength at elevated temperatures, a good performance under an intense irradiation environment, and a low neutron absorption cross section; these factors have been used to rank the applicability of a wide range of materials for structural containment Nb-1Zr has been selected for use as the structural container for the LANL ABC/ATW molten lead target. Corrosion and mass transfer behavior for various candidate structural materials in liquid lead are reviewed, together with the beneficial effects of inhibitors and various coatings to protect substrate against liquid lead corrosion. Mechanical properties of some candidate materials at elevated temperatures and the property changes resulting from 800 MeV proton irradiation are also reviewed

  16. Development of the Indigenous Child-Initiated Pretend Play Assessment: Selection of play materials and administration.

    Science.gov (United States)

    Dender, Alma; Stagnitti, Karen

    2011-02-01

    There is a need for culturally appropriate assessments for Australian Indigenous children. This article reports the selection of culturally appropriate and gender-neutral play materials, and changes in administration identified to develop further the Indigenous Child-Initiated Pretend Play Assessment (I-ChIPPA). Twenty-three typically developing children aged four to six years from the Pilbara region in Western Australia participated in the study. Children were presented with four sets of play materials and frequency counts were recorded for each time the child used one of the play materials in a pretend play action. Twelve of the 23 children came to play in pairs. Both boys and girls used the Pilbara toy set including the dark coloured dolls and Pilbara region animals, more frequently than the standardised play materials from the Child-Initiated Pretend Play Assessment (ChIPPA). This study reports the first steps in the development of the I-ChIPPA. Future development will include the refinement of the administration and scoring with pairs of children, and then validity testing the assessment. © 2010 The Authors. Australian Occupational Therapy Journal © 2010 Australian Association of Occupational Therapists.

  17. The diffusion properties of ion implanted species in selected target materials

    International Nuclear Information System (INIS)

    Alton, G.D.; Dellwo, J.; Carter, H.K.; Kormicki, J.; Bartolo, G. di; Batchelder, J.C.; Breitenbach, J.; Chediak, J.A.; Jentoff-Nilsen, K.; Ichikawa, S.

    1995-01-01

    Experiments important to the future success of the Holifield Radioactive Ion Beam Facility (HRIBF) are in progress at the Oak Ridge National Laboratory which are designed to select the most appropriate target material for generating a particular radioactive ion beam (RIB). The 25-MV HHIRF tandem accelerator is used to implant stable complements of interesting radioactive elements into refractory targets mounted in a high-temperature FEBIAD ion source which is open-quotes on-lineclose quotes at the UNISOR facility. The intensity versus time of implanted species, which diffuse from the high-temperature target material (∼1700 degrees C) and are ionized in the FEBIAD ion source, is used to determine release times for a particular projectile/target material combination. From such release data, diffusion coefficients can be derived by fitting the theoretical results obtained by computational solution of Fick's second equation to experimental data. The diffusion coefficient can be used subsequently to predict the release properties of the particular element from the same material in other target geometries and at other temperatures, provided that the activation energy is also known. Diffusion coefficients for Cl implanted into and diffused from CeS and Zr 5 Si 3 and As, Br, and Se implanted into and diffused from Zr 5 Ge 3 have been derived from the resulting intensity versus time profiles. Brief descriptions of the experimental apparatus and procedures utilized in the present experiments and plans for future related experiments are presented

  18. Selective chelation-supercritical fluid extraction of metal ions from waste materials

    International Nuclear Information System (INIS)

    Wai, C.N.; Laintz, K.E.; Yonker, C.R.

    1993-01-01

    The removal of toxic organics, metals, and radioisotopes from solids or liquids is a major concern in the treatment of industrial and nuclear wastes. For this reason, developing methods for selective separation of toxic metals and radioactive materials from solutions of complex matrix is an important problem in environmental research. Recent developments indicate supercritical fluids are good solvents for organic compounds. Many gases become supercritical fluids under moderate temperatures and pressures. For example, the critical temperature and pressure of carbon dioxide are 31 degrees C and 73 atm, respectively. The high diffusivity, low viscosity, and T-P dependence of solvent strength are some attractive properties of supercritical fluid extraction (SFE). Since CO 2 offers the additional benefits of stability and non-toxicity, the SFE technique avoids generation of organic liquid waste and exposure of personnel to toxic solvents. While direct extraction of metal ions by supercritical fluids is highly inefficient, these ions when complexed with organic ligands become quite soluble in supercritical fluids. Specific ligands can be used to achieve selective extraction of metal ions in this process. After SFE, the fluid phase can be depressurized for precipitation of the metal chelates and recycled. The ligand can also be regenerated for repeated use. The success of this selective chelation-supercritical fluid extraction (SC-SFE) process depends on a number of factors including the efficiencies of the selective chelating agents, solubilities of metal chelates in supercritical fluids, rate of extraction, ease of regeneration of the ligands, etc. In this report, the authors present recent results on the studies of the solubilities of metal chelates in supercritical CO 2 , experimental ions from aqueous solution, and the development of selective chelating agents (ionizable crown ethers) for the extraction of lanthanides and actinides

  19. Evolutionary selection growth of two-dimensional materials on polycrystalline substrates

    Science.gov (United States)

    Vlassiouk, Ivan V.; Stehle, Yijing; Pudasaini, Pushpa Raj; Unocic, Raymond R.; Rack, Philip D.; Baddorf, Arthur P.; Ivanov, Ilia N.; Lavrik, Nickolay V.; List, Frederick; Gupta, Nitant; Bets, Ksenia V.; Yakobson, Boris I.; Smirnov, Sergei N.

    2018-03-01

    There is a demand for the manufacture of two-dimensional (2D) materials with high-quality single crystals of large size. Usually, epitaxial growth is considered the method of choice1 in preparing single-crystalline thin films, but it requires single-crystal substrates for deposition. Here we present a different approach and report the synthesis of single-crystal-like monolayer graphene films on polycrystalline substrates. The technological realization of the proposed method resembles the Czochralski process and is based on the evolutionary selection2 approach, which is now realized in 2D geometry. The method relies on `self-selection' of the fastest-growing domain orientation, which eventually overwhelms the slower-growing domains and yields a single-crystal continuous 2D film. Here we have used it to synthesize foot-long graphene films at rates up to 2.5 cm h-1 that possess the quality of a single crystal. We anticipate that the proposed approach could be readily adopted for the synthesis of other 2D materials and heterostructures.

  20. Selected mechanical properties of aluminum composite materials reinforced with SiC particles

    Directory of Open Access Journals (Sweden)

    A. Kurzawa

    2008-07-01

    Full Text Available This work presents the results of research concerning influence of ceramic particles’ content of silicon carbide on selected mechanical properties of type AW-AlCu4Mg2Mn - SiC composite materials. Composites produced of SiC particles with pressure infiltration method of porous preform and subject to hot plastic forming in the form of open die forging were investigated. The experimental samples contained from 5% up to 45% of reinforcing SiC particles of 8÷10μm diameter. Studies of strength properties demonstrated that the best results, in case of tensile strength as well as offset yield strength, might be obtained while applying reinforcement in the amount of 20-25% vol. of SiC. Application of higher than 25% vol. contents of reinforcing particles leads to gradual strength loss. The investigated composites were characterized by very high functional properties, such as hardness and abrasive wear resistance, whose values increase strongly with the increase of reinforcement amount. The presented results of the experiments shall allow for a more precise component selection of composite materials at the stage of planning and design of their properties.

  1. Ethnography of Cool Roof Retrofits: The Role of Rebates in the Materials Selection Process

    Energy Technology Data Exchange (ETDEWEB)

    Mazur-Stommen, Susan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2011-02-01

    In the summer of 2010, ethnographic research was conducted with nine households in the Bay Area and Sacramento region. The purpose of this task was to collect methodologically grounded insights into how and why consumers chose the cool roofing material they selected. These nine households comprised fifteen respondents, and their dependents. They were selected from among a pool of respondents to a mail solicitation of all Sacramento Municipal Utility District and Pacific Gas and Electric customers who had received a rebate for their cool roof retrofit. Consumers are uniformly happy with their cool roof retrofits. Consumers typically stayed very close to the aesthetic of the original roof style. Price was not a primary concern, while longevity was paramount. Consumers did not use roofing price, nor energy savings (with one exception), in tracking return on investment through energy savings. The utility rebate had little role to play in terms of incentivizing customers to choose cool materials. Contractors were critical partners in the decision-­making process.

  2. Óleo funcional na dieta de vacas leiteiras

    OpenAIRE

    Jesus, Elmeson Ferreira de [UNESP

    2015-01-01

    O presente estudo teve como objetivo avaliar os efeitos da inclusão de óleo funcional composto de ácido anacárdico, cardol e cardanol (óleo da castanha de cajú) e ácido ricinoleico (óleo de mamona) na dieta de vacas em lactação sobre consumo, digestibilidade aparente total da matéria seca e nutrientes, fermentação ruminal, produção e composição do leite, síntese de proteína microbiana, perfil metabólico, balanço de nitrogênio e energia. Foram utilizadas vinte e quatro vacas pluriparas da raça...

  3. Influence of material selection on the structural behavior of a wave energy converter

    Directory of Open Access Journals (Sweden)

    Cândida M. S. P. Malça

    2014-09-01

    Full Text Available In the last decades, the world energy demand has raised significantly. Concerning this fact, wave energy should be considered as a valid alternative for electricity production. Devices suitable to harness this kind of renewable energy source and convert it into electricity are not yet commercially competitive. This paper is focused on the selection and analysis of different types of elastic materials and their influence on the structural behavior of a wave energy converter (WEC. After a brief characterization of the device, a tridimensional computer aided design (3D CAD numerical model was built and several finite element analyses (FEA were performed through a commercial finite element code. The main components of the WEC, namely the buoy, supporting cables and hydraulic cylinder were simulated assuming different materials. The software used needs, among other parameters, the magnitude of the resultant hydrodynamic forces acting upon the floating buoy obtained from a WEC time domain simulator (TDS which was built based on the WEC dynamic model previously developed. The Von Mises stress gradients and displacement fields determined by the FEA demonstrated that, regardless of the WEC component, the materials with low Young's modulus seems to be unsuitable for this kind of application. The same is valid for the material yield strength since materials with a higher yield strength lead to a better structural behavior of WEC components because lower stress and displacement values were obtained. The developed 3D CAD numerical model showed to be suitable to analyze different combinations of structural conditions. They could depend of different combinations of buoy position and resultant hydrodynamic forces acting upon the buoy, function of the specific sea wave parameters found on the deployment site.

  4. The Komplast Experiment: Space Environmental Effects after 12 Years in LEO (and Counting)

    Science.gov (United States)

    Golden, J. L.; Shaevich, S.; Aleksandrov, N. G.; Shumov, A. E.; Novikov, L. S.; Alred, J. A.; Shindo, D. J.; Kravchenko, M.

    2014-01-01

    The Komplast materials experiment was designed by the Khrunichev Space Center, together with other Russian scientific institutes, and has been carried out by Mission Control Moscow since 1998. The purpose is to study the effect of the low earth orbit (LEO) environment on exposed samples of various spacecraft materials. The Komplast experiment began with the launch of the first International Space Station (ISS) module on November 20, 1998. Two of eight experiment panels were retrieved during Russian extravehicular activity in February 2011 after 12 years of LEO exposure, and were subsequently returned to Earth by Space Shuttle "Discovery" on the STS-133/ULF-5 mission. The retrieved panels contained an experiment to detect micrometeoroid and orbital debris (MMOD) impacts, radiation sensors, a temperature sensor, several pieces of electrical cable, both carbon composite and adhesive-bonded samples, and many samples made from elastomeric and fluoroplastic materials. Our investigation is complete and a summary of the results obtained from this uniquely long-duration exposure experiment will be presented.

  5. Microstructure and Magnetic Properties of Magnetic Material Fabricated by Selective Laser Melting

    Science.gov (United States)

    Jhong, Kai Jyun; Huang, Wei-Chin; Lee, Wen Hsi

    Selective Laser Melting (SLM) is a powder-based additive manufacturing which is capable of producing parts layer-by-layer from a 3D CAD model. The aim of this study is to adopt the selective laser melting technique to magnetic material fabrication. [1]For the SLM process to be practical in industrial use, highly specific mechanical properties of the final product must be achieved. The integrity of the manufactured components depend strongly on each single laser-melted track and every single layer, as well as the strength of the connections between them. In this study, effects of the processing parameters, such as the space distance of surface morphology is analyzed. Our hypothesis is that when a magnetic product is made by the selective laser melting techniques instead of traditional techniques, the finished component will have more precise and effective properties. This study analyzed the magnitudes of magnetic properties in comparison with different parameters in the SLM process and compiled a completed product to investigate the efficiency in contrast with products made with existing manufacturing processes.

  6. Deuterium pumping and erosion behavior of selected graphite materials under high flux plasma bombardment in PISCES

    International Nuclear Information System (INIS)

    Hirooka, Y.; Conn, R.W.; Goebel, D.M.; LaBombard, B.; Lehmer, R.; Leung, W.K.; Nygren, R.E.; Ra, Y.

    1988-06-01

    Deuterium plasma recycling and chemical erosion behavior of selected graphite materials have been investigated using the PISCES-A facility. These materials include: Pyro-graphite; 2D-graphite weave; 4D-graphite weave; and POCO-graphite. Deuterium plasma bombardment conditions are: fluxes around 7 /times/ 10 17 ions s/sup /minus/1/cm/sup /minus/2/; exposure time in the range from 10 to 100 s; bombarding energy of 300 eV; and graphite temperatures between 20 and 120/degree/C. To reduce deuterium plasma recycling, several approaches have been investigated. Erosion due to high-fluence helium plasma conditioning significantly increases the surface porosity of POCO-graphite and 4D-graphite weave whereas little change for 2D-graphite weave and Pyro-graphite. The increased pore openings and refreshed in-pore surface sites are found to reduce the deuterium plasma recycling and chemical erosion rates at transient stages. The steady state recycling rates for these graphite materials can be also correlated to the surface porosity. Surface topographical modification by machined-grooves noticeably reduces the steady state deuterium recycling rate and the impurity emission from the surface. These surface topography effects are attributed to co-deposition of remitted deuterium, chemically sputtered hydrocarbon and physically sputtered carbon under deuterium plasma bombardment. The co-deposited film is found to have a characteristic surface morphology with dendritic microstructures. 18 ref., 4 figs., 1 tab

  7. Material selection and assembly method of battery pack for compact electric vehicle

    Science.gov (United States)

    Lewchalermwong, N.; Masomtob, M.; Lailuck, V.; Charoenphonphanich, C.

    2018-01-01

    Battery packs become the key component in electric vehicles (EVs). The main costs of which are battery cells and assembling processes. The battery cell is indeed priced from battery manufacturers while the assembling cost is dependent on battery pack designs. Battery pack designers need overall cost as cheap as possible, but it still requires high performance and more safety. Material selection and assembly method as well as component design are very important to determine the cost-effectiveness of battery modules and battery packs. Therefore, this work presents Decision Matrix, which can aid in the decision-making process of component materials and assembly methods for a battery module design and a battery pack design. The aim of this study is to take the advantage of incorporating Architecture Analysis method into decision matrix methods by capturing best practices for conducting design architecture analysis in full account of key design components critical to ensure efficient and effective development of the designs. The methodology also considers the impacts of choice-alternatives along multiple dimensions. Various alternatives for materials and assembly techniques of battery pack are evaluated, and some sample costs are presented. Due to many components in the battery pack, only seven components which are positive busbar and Z busbar are represented in this paper for using decision matrix methods.

  8. Materials selection, qualification and manufacturing of the in-vessel divertor cryopump for JET

    International Nuclear Information System (INIS)

    Papastergiou, S.; Obert, W.; Thompson, E.

    1994-01-01

    The introduction of a cryopump into the interior of a large tokamak raises several technical problems related to the thermal stresses, eddy current forces and choice of materials. The JET divertor cryopump has been optimized in terms of stresses, flow stability and operation - the liquid nitrogen cooled chevron structure in particular having to fulfill conflicting requirements at cryogenic temperatures. These requirements include good thermal conductivity in order to minimize thermal gradients (to reduce the radiative heat load onto the liquid helium circuit), high electrical resistivity (to minimize eddy current stresses), high mechanical strength and good mechanical formability. This paper reports on the materials selection based on measurements of properties at cryogenic and elevated temperatures and the development of an optimized thermal treatment combining solution heat treatment, brazing and precipitation hardening. It also reports on the successful development of various manufacturing technologies which have been employed including (a) techniques for brazing of the chosen copper alloy onto inconel and stainless steel, (b) surface blackening of the copper alloy with plasma sprayed ceramic coatings that are vacuum compatible and able to withstand temperatures between 70 K and 1135 K and (c) plasma spray deposition of copper onto stainless steel in order to produce an anisotropic composite material with improved thermal conductivity, high strength and high electrical resistivity for use at temperatures between 70 K and 650 K

  9. Variable stars in the Leo A dwarf galaxy (DDO 69)

    Science.gov (United States)

    Hoessel, John G.; Saha, A.; Krist, John; Danielson, G. Edward

    1994-01-01

    Observations of the Leo A dwarf galaxy, obtained over the period from 1980 to 1991 are reported. Forty two separate Charge Coupled Devices (CCD) frames were searched for variable stars. A total of 14 suspected variables were found, 9 had sufficient coverage for period determination, and 5 had Cepheid light curves. Four of these stars fit well on a P-L relation and yield a distance modulus, after correction for Galactic foreground extinction, of m-M = 26.74. This corresponds to a distance of 2.2 Mpc, placing Leo A near the Local Group zero-velocity surface.

  10. El petróleo como repelente de Phlebotomus

    Directory of Open Access Journals (Sweden)

    Marshall Hertig

    1943-09-01

    Full Text Available Se ha probado el repelente del petróleo contra el Phlebotomus verrucarum. Se echó varias veces petróleo en las paredes exteriores y en el suelo alrededor de casas en la zona verrucógena del Rímac, donde son abundantes las titiras. Inmediatamente después de cada petrolización se redujeron a números insignificantes las titiras dentro de las casas, efecto que duró aproximadamente una semana.

  11. Determinações preliminares do teor de óleo essencial em camomila cultivada no Brasil Preliminary determination of essential oil content in camomile growing in Brasil

    OpenAIRE

    Mario Guilherme Roberto Donalisio

    1985-01-01

    Amostras de capítulos florais, pedúnculos florais e caules de camomila cultivada no Brasil foram destiladas em aparelho destilador de Clevenger para avaliação dos respectivos teores de óleo essencial, sendo encontrados os seguintes valores médios por material destilado: capítulos florais: 0,421%; pedúnculos florais: 0,132% e caules:0,0251 %. Os valores percentuais de óleo essencial relativos a capítulos florais são comparáveis aos encontrados em camomila produzida em diversos países produtore...

  12. Preliminary materials selection issues for the next generation nuclear plant reactor pressure vessel.

    Energy Technology Data Exchange (ETDEWEB)

    Natesan, K.; Majumdar, S.; Shankar, P. S.; Shah, V. N.; Nuclear Engineering Division

    2007-03-21

    In the coming decades, the United States and the entire world will need energy supplies to meet the growing demands due to population increase and increase in consumption due to global industrialization. One of the reactor system concepts, the Very High Temperature Reactor (VHTR), with helium as the coolant, has been identified as uniquely suited for producing hydrogen without consumption of fossil fuels or the emission of greenhouse gases [Generation IV 2002]. The U.S. Department of Energy (DOE) has selected this system for the Next Generation Nuclear Plant (NGNP) Project, to demonstrate emissions-free nuclear-assisted electricity and hydrogen production within the next 15 years. The NGNP reference concepts are helium-cooled, graphite-moderated, thermal neutron spectrum reactors with a design goal outlet helium temperature of {approx}1000 C [MacDonald et al. 2004]. The reactor core could be either a prismatic graphite block type core or a pebble bed core. The use of molten salt coolant, especially for the transfer of heat to hydrogen production, is also being considered. The NGNP is expected to produce both electricity and hydrogen. The process heat for hydrogen production will be transferred to the hydrogen plant through an intermediate heat exchanger (IHX). The basic technology for the NGNP has been established in the former high temperature gas reactor (HTGR) and demonstration plants (DRAGON, Peach Bottom, AVR, Fort St. Vrain, and THTR). In addition, the technologies for the NGNP are being advanced in the Gas Turbine-Modular Helium Reactor (GT-MHR) project, and the South African state utility ESKOM-sponsored project to develop the Pebble Bed Modular Reactor (PBMR). Furthermore, the Japanese HTTR and Chinese HTR-10 test reactors are demonstrating the feasibility of some of the planned components and materials. The proposed high operating temperatures in the VHTR place significant constraints on the choice of material selected for the reactor pressure vessel for

  13. Study of Material Consolidation at Higher Throughput Parameters in Selective Laser Melting of Inconel 718

    Science.gov (United States)

    Prater, Tracie

    2016-01-01

    Selective Laser Melting (SLM) is a powder bed fusion additive manufacturing process used increasingly in the aerospace industry to reduce the cost, weight, and fabrication time for complex propulsion components. SLM stands poised to revolutionize propulsion manufacturing, but there are a number of technical questions that must be addressed in order to achieve rapid, efficient fabrication and ensure adequate performance of parts manufactured using this process in safety-critical flight applications. Previous optimization studies for SLM using the Concept Laser M1 and M2 machines at NASA Marshall Space Flight Center have centered on machine default parameters. The objective of this work is to characterize the impact of higher throughput parameters (a previously unexplored region of the manufacturing operating envelope for this application) on material consolidation. In phase I of this work, density blocks were analyzed to explore the relationship between build parameters (laser power, scan speed, hatch spacing, and layer thickness) and material consolidation (assessed in terms of as-built density and porosity). Phase II additionally considers the impact of post-processing, specifically hot isostatic pressing and heat treatment, as well as deposition pattern on material consolidation in the same higher energy parameter regime considered in the phase I work. Density and microstructure represent the "first-gate" metrics for determining the adequacy of the SLM process in this parameter range and, as a critical initial indicator of material quality, will factor into a follow-on DOE that assesses the impact of these parameters on mechanical properties. This work will contribute to creating a knowledge base (understanding material behavior in all ranges of the AM equipment operating envelope) that is critical to transitioning AM from the custom low rate production sphere it currently occupies to the world of mass high rate production, where parts are fabricated at a rapid

  14. A prototype knowledge-based system for material selection of ceramic matrix composites of automotive engine components

    Energy Technology Data Exchange (ETDEWEB)

    Sapuan, S.M.; Jacob, M.S.D.; Mustapha, F.; Ismail, N

    2002-12-15

    A prototype knowledge based system (KBS) for material selection of ceramic matrix composites (CMC) for engine components such as piston, connecting rod and piston ring is proposed in this paper. The main aim of this research work is to select the most suitable material for the automotive engine components. The selection criteria are based upon the pre-defined constraint value. The constraint values are mechanical, physical properties and manufacturing techniques. The constraint values are the safety values for the product design. The constraint values are selected from the product design specification. The product design specification values are selected from the past design calculation and some values are calculated by the help of past design data. The knowledge-based system consists of several modules such as knowledge acquisition module, inference module and user interface module. The domains of the knowledge-based system are defined as objects and linked together by hierarchical graph. The system is capable of selecting the most suitable materials and ranks the materials with respect to their properties. The design engineers can choose the required materials related to the materials property.

  15. Selective Preparation of Furfural from Xylose over Sulfonic Acid Functionalized Mesoporous Sba-15 Materials

    Directory of Open Access Journals (Sweden)

    Panpan Li

    2011-04-01

    Full Text Available Sulfonic acid functionalized mesoporous SBA-15 materials were prepared using the co-condensation and grafting methods, respectively, and their catalytic performance in the dehydration of xylose to furfural was examined. SBA-15-SO3H(C prepared by the co-condensation method showed 92–95% xylose conversion and 74% furfural selectivity, and 68–70% furfural yield under the given reaction conditions. The deactivation and regeneration of the SBA-15-SO3H(C catalyst for the dehydration of xylose was also investigated. The results indicate that the used and regeneration catalysts retained the SBA-15 mesoporous structure, and the S content of SBA-15-SO3H(C almost did not change. The deactivation of the catalysts is proposed to be associated with the accumulation of byproducts, which is caused by the loss reaction of furfural. After regeneration by H2O2, the catalytic activity of the catalyst almost recovered.

  16. Selection of refractory materials for acid tanks at the CSN continuous pickling line

    International Nuclear Information System (INIS)

    Silva, Sidiney Nascimento; Marques, Oscar Rosa; Bueno, Mauricio Chaves; Longo, Elson; Silva Pinheiro, Adriano da

    1997-01-01

    Aiming at the revamping of the CSN continuous pickling line 4 acid tanks, a Post Mortem study of the refractory lining was carried out. The collected samples were characterized through techniques such as chemical analysis, mercury porosimetry, X-ray diffraction and scanning electronic microscopy. Trying to reproduce the operational conditions closely, laboratorial simulations were carried out. Such simulations lead to the addition of some alterations on the test method proposed by ABNT. Primarily, the sulfuric acid was substituted by hydrochloric acid (30%), containing iron in solution (130g/l). As result, it was concluded that acid resistant refractories containing a smaller alumina and /or corundum and mullite concentrations, presenting a smaller open porosity and average pore diameter, have a better performance face to corrosion due to hydrochloric acid solution. In addition, abrasion wear resistance tests, according to the ASTM-G65-85 standard were carried out in order to select different materials to the acid tanks cells. (author)

  17. Selective Laser Melting of Hot Gas Turbine Components: Materials, Design and Manufacturing Aspects

    DEFF Research Database (Denmark)

    Goutianos, Stergios

    2017-01-01

    are built additively to nearly net shape. This allows the fabrication of arbitrary complex geometries that cannot be made by conventional manufacturing techniques. However, despite the powerful capabilities of SLM, a number of issues (e.g. part orientation, support structures, internal stresses), have......Selective Laser Melting (SLM) allows the design and manufacturing of novel parts and structures with improved performance e.g. by incorporating complex and more efficient cooling schemes in hot gas turbine parts. In contrast to conventional manufacturing of removing material, with SLM parts...... to be considered in order to manufacture cost-effective and high quality parts at an industrial scale. These issues are discussed in the present work from an engineering point of view with the aim to provide simple quidelines to produce high quality SLM parts....

  18. Selection of Liner Materials and Design of Hazardous Water Facilities in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Sahel N. Abduljauwad

    2001-12-01

    Full Text Available Rapid development in Saudi Arabia has produced a broad spectrum of wastes.  In the last two decades, several refineries and petrochemical industries have been established. These industries have produced sludges and other toxic wastes which need proper planning for their handling and disposal. This paper covers design and selection of liner materials for two hazardous waste disposal sites. One of them is located in the Eastern Province of Saudi Arabia, while the second one is located in the Western part. The paper will present complete design details of the natural compacted and geosynthetic soil liners and the leachate collection and removal system for primary liners and leak detection/leachate collection and removal system for secondary liners.

  19. Materials selection of surface coatings in an advanced size reduction facility

    International Nuclear Information System (INIS)

    Briggs, J.L.; Younger, A.F.

    1980-01-01

    A materials selection test program was conducted to characterize optimum interior surface coatings for an advanced size reduction facility. The equipment to be processed by this facility consists of stainless steel apparatus (e.g., glove boxes, piping, and tanks) used for the chemical recovery of plutonium. Test results showed that a primary requirement for a satisfactory coating is ease of decontamination. A closely related concern is the resistance of paint films to nitric acid - plutonium environments. A vinyl copolymer base paint was the only coating, of eight paints tested, with properties that permitted satisfactory decontamination of plutonium and also performed equal to or better than the other paints in the chemical resistance, radiation stability, and impact tests

  20. Core–shell-typed Ag-SiO2 nanoparticles as solar selective coating materials

    International Nuclear Information System (INIS)

    Gao, Tao; Jelle, Bjørn Petter; Gustavsen, Arild

    2013-01-01

    Silver (Ag) nanoparticles with typical diameter of about 50 nm have been prepared via a polyol process. The as-prepared Ag nanoparticles are well crystallized and exhibit a characteristic surface plasmon resonance (SPR) band centered at ∼423 nm. The SPR band shows a strong dependence on the sizes of Ag nanoparticles and the types of the dielectric medium. Core–shell-typed Ag-SiO 2 nanoparticles have also been prepared by depositing a thin layer (∼25 nm) of silica on Ag nanoparticles. The core–shell-typed Ag-SiO 2 nanoparticles show similar optical behaviors (absorption, transmission, and reflection) but enhanced stability compared to those of the Ag nanoparticles, indicating that the core–shell-typed Ag-SiO 2 nanoparticles may be used as solar selective coating materials for architectural window applications.

  1. A Study of the Influence of Advertising Techniques on Selection of Instructional Reading Materials by Prospective Teachers.

    Science.gov (United States)

    Greenlaw, M. Jean; And Others

    This study examined the effect of three different modes of presentation on elementary education majors' selection and rating of materials for reading instruction. Materials were chosen to represent each of the following propaganda techniques: glittering generalities, name calling, transfer, testimonial, bandwagon, and card stacking. Students in…

  2. A Guide to Selected Curriculum Materials on Interdependence, Conflict, and Change: Teacher Comments on Classroom Use and Implementation.

    Science.gov (United States)

    New York Friends Group, Inc., New York. Center for War/Peace Studies.

    The purpose of this compilation of teacher-developed descriptive evaluations of curriculum materials is to provide practical guidance to available materials dealing with the selected themes of interdependence, conflict, and change. Each of six conceptual units presented on change, conflict, identity, interdependence, power and authority, and…

  3. Cell Adhesion Selectivity of Stent Material to improve Bio-functionality by Ion Beam Modification

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jaesang; Park, JUngchan; Jung, Myunghwan; Kim, Yongki [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Park, Junkyu [Bio alpha., Co. Ltd., Gimhae (Korea, Republic of)

    2014-05-15

    In this study, ion implantation into collagen coated Co-Cr alloy, which is a cheaper material of the artificial stent product comparing with Ti alloy, has been studied to develop small diameter artificial stent by the cell adhesion control. The size of stent was 1.6mm of the diameter and 18mm of the length. The life-time of artificial stent depends on adhesion property of endothelial-cells. We successfully controlled cell adhesion selectivity between endothelial cell and muscle cell by using collagen coated and He{sup +} ion beam irradiated Co-Cr-alloy to apply to artificial stent. But, we did not achieve the inhibition of platelet adhesion, yet by using collagen coating and He{sup +} ion beam irradiation. Based on this study, we have plan to research about separation between collagen coating effect and ion beam effect. Also, we will have more detail analysis of the mechanism of cell attachment. In recent years, ion implantation has been applied to the surface modification of prosthesis to improve blood compatibility and tissue compatibility in field of biomedical application. As well known, bio compatibility was concerned with the cell adhesion selectivity for bio-functionality. The biomedical application of ion beam technology would be used more widely in the future such as catheter and artificial graft.

  4. Cell Adhesion Selectivity of Stent Material to improve Bio-functionality by Ion Beam Modification

    International Nuclear Information System (INIS)

    Lee, Jaesang; Park, JUngchan; Jung, Myunghwan; Kim, Yongki; Park, Junkyu

    2014-01-01

    In this study, ion implantation into collagen coated Co-Cr alloy, which is a cheaper material of the artificial stent product comparing with Ti alloy, has been studied to develop small diameter artificial stent by the cell adhesion control. The size of stent was 1.6mm of the diameter and 18mm of the length. The life-time of artificial stent depends on adhesion property of endothelial-cells. We successfully controlled cell adhesion selectivity between endothelial cell and muscle cell by using collagen coated and He + ion beam irradiated Co-Cr-alloy to apply to artificial stent. But, we did not achieve the inhibition of platelet adhesion, yet by using collagen coating and He + ion beam irradiation. Based on this study, we have plan to research about separation between collagen coating effect and ion beam effect. Also, we will have more detail analysis of the mechanism of cell attachment. In recent years, ion implantation has been applied to the surface modification of prosthesis to improve blood compatibility and tissue compatibility in field of biomedical application. As well known, bio compatibility was concerned with the cell adhesion selectivity for bio-functionality. The biomedical application of ion beam technology would be used more widely in the future such as catheter and artificial graft

  5. Review of Mid- to High-Temperature Solar Selective Absorber Materials

    Energy Technology Data Exchange (ETDEWEB)

    Kennedy, C. E.

    2002-07-01

    This report describes the concentrating solar power (CSP) systems using solar absorbers to convert concentrated sunlight to thermal electric power. It is possible to achieve solar absorber surfaces for efficient photothermal conversion having high solar absorptance (a) for solar radiation and a low thermal emittance (e) at the operational temperature. A low reflectance (?'' 0) at wavelengths (?) 3 mm and a high reflectance (?'' 1) at l 3 mm characterize spectrally selective surfaces. The operational temperature ranges of these materials for solar applications can be categorized as low temperature (T< 100 C), mid-temperature (100 C< T< 400 C), and high-temperature (T> 400 C). High- and mid-temperature applications are needed for CSP applications. For CSP applications, the ideal spectrally selective surface would be low-cost and easy to manufacture, chemically and thermally stable in air at elevated operating temperatures (T= 500 C), and have a solar absorptance= 0.98 and a thermal emittance= 0.05 at 500 C.

  6. Investigation of Methods for Selectively Reinforcing Aluminum and Aluminum-Lithium Materials

    Science.gov (United States)

    Bird, R. Keith; Alexa, Joel A.; Messick, Peter L.; Domack, Marcia S.; Wagner, John A.

    2013-01-01

    Several studies have indicated that selective reinforcement offers the potential to significantly improve the performance of metallic structures for aerospace applications. Applying high-strength, high-stiffness fibers to the high-stress regions of aluminum-based structures can increase the structural load-carrying capability and inhibit fatigue crack initiation and growth. This paper discusses an investigation into potential methods for applying reinforcing fibers onto the surface of aluminum and aluminum-lithium plate. Commercially-available alumina-fiber reinforced aluminum alloy tapes were used as the reinforcing material. Vacuum hot pressing was used to bond the reinforcing tape to aluminum alloy 2219 and aluminum-lithium alloy 2195 base plates. Static and cyclic three-point bend testing and metallurgical analysis were used to evaluate the enhancement of mechanical performance and the integrity of the bond between the tape and the base plate. The tests demonstrated an increase in specific bending stiffness. In addition, no issues with debonding of the reinforcing tape from the base plate during bend testing were observed. The increase in specific stiffness indicates that selectively-reinforced structures could be designed with the same performance capabilities as a conventional unreinforced structure but with lower mass.

  7. In memoriam Prof. Dr. Leo Daniel Brongersma (1907-1994)

    NARCIS (Netherlands)

    Hoogmoed, M.S.

    1995-01-01

    A biography of Leo Daniel Brongersma is given, highlighting his significance for herpetology worldwide, and especially for snake anatomy, sea turtle distribution, faunistics of New Guinea and IndoAustralia. Lists of patronyms, of species named by Brongersma and of his publications are given. Also

  8. Satellite Telemetry and Command using Big LEO Mobile Telecommunications Systems

    Science.gov (United States)

    Huegel, Fred

    1998-01-01

    Various issues associated with satellite telemetry and command using Big LEO mobile telecommunications systems are presented in viewgraph form. Specific topics include: 1) Commercial Satellite system overviews: Globalstar, ICO, and Iridium; 2) System capabilities and cost reduction; 3) Satellite constellations and contact limitations; 4) Capabilities of Globalstar, ICO and Iridium with emphasis on Globalstar; and 5) Flight transceiver issues and security.

  9. Complete mitochondrial genome of a Asian lion (Panthera leo goojratensis).

    Science.gov (United States)

    Li, Yu-Fei; Wang, Qiang; Zhao, Jian-ning

    2016-01-01

    The entire mitochondrial genome of this Asian lion (Panthera leo goojratensis) was 17,183 bp in length, gene composition and arrangement conformed to other lions, which contained the typical structure of 22 tRNAs, 2 rRNAs, 13 protein-coding genes and a non-coding region. The characteristic of the mitochondrial genome was analyzed in detail.

  10. Moore'i seadus ja meie tulevik / Leo Võhandu

    Index Scriptorium Estoniae

    Võhandu, Leo, 1929-

    2006-01-01

    Kiibifirma Intel üks asutajaid Gordon Moore väitis 1965. aastal, et transistorite arv kiibil topeldub iga kahe aastaga ehk loomulik areng ei ole lineaarne, vaid eksponentsiaalne (astmeline). TTÜ emeriitprofessor Moore'i seaduse mõjust ühiskonna arengule. Vt. samas: Leo Võhandu

  11. Haemangiosarcoma in a captive Asiatic lion ( Panthera leo persica ...

    African Journals Online (AJOL)

    A 2.7-year-old male captive Asiatic lion (Panthera leo persica) died unexpectedly without preceding symptoms. Gross necropsy revealed liver and lung tumours, which proved to be haemangiosarcomas by histopathology. Some of the liver tumours were ruptured, leading to massive intra-abdominal haemorrhage and death.

  12. Estimation of the lion ( Panthera leo ) population in the southwestern ...

    African Journals Online (AJOL)

    A previous estimate of the lion (Panthera leo) population in the southwestern Kgalagadi Transfrontier Park (KTP) was made over 20 years ago. This together with increased fears regarding the viability of the population as a result of recent killings of roaming animals, an observed increase in non-violent mortalities during ...

  13. Normalization Methods and Selection Strategies for Reference Materials in Stable Isotope Analyses - Review

    International Nuclear Information System (INIS)

    Skrzypek, G.; Sadler, R.; Paul, D.; Forizs, I.

    2011-01-01

    A stable isotope analyst has to make a number of important decisions regarding how to best determine the 'true' stable isotope composition of analysed samples in reference to an international scale. It has to be decided which reference materials should be used, the number of reference materials and how many repetitions of each standard is most appropriate for a desired level of precision, and what normalization procedure should be selected. In this paper we summarise what is known about propagation of uncertainties associated with normalization procedures and propagation of uncertainties associated with reference materials used as anchors for the determination of 'true' values for δ''1''3C and δ''1''8O. Normalization methods Several normalization methods transforming the 'raw' value obtained from mass spectrometers to one of the internationally recognized scales has been developed. However, as summarised by Paul et al. different normalization transforms alone may lead to inconsistencies between laboratories. The most common normalization procedures are: single-point anchoring (versus working gas and certified reference standard), modified single-point normalization, linear shift between the measured and the true isotopic composition of two certified reference standards, two-point and multipoint linear normalization methods. The accuracy of these various normalization methods has been compared by using analytical laboratory data by Paul et al., with the single-point and normalization versus tank calibrations resulting in the largest normalization errors, and that also exceed the analytical uncertainty recommended for δ 13 C. The normalization error depends greatly on the relative differences between the stable isotope composition of the reference material and the sample. On the other hand, the normalization methods using two or more certified reference standards produces a smaller normalization error, if the reference materials are bracketing the whole range of

  14. Ceramic Materials Selection of Fuel Crucibles based on Plasma Spray Coating for SFR

    Energy Technology Data Exchange (ETDEWEB)

    Song, Hoon; Kim, Jonghwan; Kim, Hyungtae; Ko, Youngmo; Woo, Yoonmyung; Oh, Seokjin; Kim, Kihwan; Lee, Chanbock [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-07-01

    The plasma-sprayed coating can provide the crucible with a denser, more friable coating layer, compared with the more friable coating layer formed by slurry-coating, which was used to prevent the interaction between melt and crucibles. Plasma-sprayed coatings are consolidated by mechanical interlocking of the molten particles impacting on the substrate and are dense by the heat applied by the plasma. The increased coating density is advantageous because it should not require frequent re coating and U-Zr melt penetration through the protective layer is more difficult in a dense coating than in a porous coating. In this study, we used Vacuum Plasma Spray method to investigate permanent coatings for re-usable crucibles for melting and casting of metallic fuel onto niobium substrates. Niobium was selected as a substrate because of its refractory nature and the coefficient of thermal expansion is similar to that of many of the candidate materials. After the HfC, ZrC, TiC, TaC, Y{sub 2}O{sub 3}, and 8% YSZ coatings were applied the resulting microstructure and chemical compositions was characterized to find the optimum process conditions for coating. Thermal plasma-sprayed coatings of refractory materials can be applied to develop a re-usable crucible coating for metallic fuel, such as the U-Zr alloy proposed for sodium cooled fast reactors.

  15. Gamma activity as a guide for the building raw materials selection and controlling the environmental hazards

    Directory of Open Access Journals (Sweden)

    T. Ibrahim

    2012-06-01

    Full Text Available The spectrometric measurements can provide an alarm for the radiation activity and radioelement concentra-tions. The activity increase over the ambient background can be achieved by well calibrated gamma-spectrometers. In comparison between Wadi El-Dahl and Abu Zawal quarries for building raw materials (feld-spar, the activity concentration of El-Dahl stream sediments are 54.5 and 44.5 Bq/kg for uranium and thorium respectively. While the activity concentration of Abu Zawal rock quarry are 167.03 and 79.77 Bq/kg for uranium and thorium respectively. These activities yielding effective dose rates of 0.63 mSv/y for Wadi El-Dahl stream sediments and 1.48 mSv/y for Abu Zawal rock quarry. In summary, the spectrometric measurements are excellent selective tool to monitoring the environment against the radiation risk. In this aspect, Wadi El-Dahl stream sedi-ment quarry considered as the more suitable for producing feldspar as a raw materials to building industry. In comparison, Abu Zawal rock quarry has a higher effective dose rate exceeds the international permissible limits which is 1 mSv/y. A total of 19 feldspar samples were completely described regarding their general chemical fea-tures by using x-ray fluorescence. From the study all the samples contain high concentration of barium and ru-bidium which can separate using different methods in order to use in different important industry.

  16. An integrated approach of topology optimized design and selective laser melting process for titanium implants materials.

    Science.gov (United States)

    Xiao, Dongming; Yang, Yongqiang; Su, Xubin; Wang, Di; Sun, Jianfeng

    2013-01-01

    The load-bearing bone implants materials should have sufficient stiffness and large porosity, which are interacted since larger porosity causes lower mechanical properties. This paper is to seek the maximum stiffness architecture with the constraint of specific volume fraction by topology optimization approach, that is, maximum porosity can be achieved with predefine stiffness properties. The effective elastic modulus of conventional cubic and topology optimized scaffolds were calculated using finite element analysis (FEA) method; also, some specimens with different porosities of 41.1%, 50.3%, 60.2% and 70.7% respectively were fabricated by Selective Laser Melting (SLM) process and were tested by compression test. Results showed that the computational effective elastic modulus of optimized scaffolds was approximately 13% higher than cubic scaffolds, the experimental stiffness values were reduced by 76% than the computational ones. The combination of topology optimization approach and SLM process would be available for development of titanium implants materials in consideration of both porosity and mechanical stiffness.

  17. "Winterização" de óleo de pescado via solvente Winterization of fish oil with solvent

    Directory of Open Access Journals (Sweden)

    Daniele Colembergue Cunha

    2009-03-01

    Full Text Available O fracionamento de óleos via "winterização" consiste numa cristalização fracionada, na qual os triacilgliceróis de óleos e gorduras são separados pela cristalização parcial na fase líquida. O objetivo deste trabalho consistiu na determinação das variáveis significativas e das condições operacionais do processo de "winterização" via solvente do óleo de pescado. Como matéria-prima empregou-se o óleo de pescado bruto de indústrias pesqueiras, o qual foi branqueado. Na etapa de "winterização", o óleo branqueado foi resfriado progressivamente em três estágios, de 30 ºC até -5 ºC. Foram estudados os seguintes fatores: tipo de solvente, proporção de solvente e agitação no segundo estágio do resfriamento. As composições de ácidos graxos dos óleos de pescado foram determinadas através de cromatografia gasosa. Foram analisadas as variações percentuais dos ácidos graxos insaturados e dos ácidos graxos saturados. As condições recomendadas para o processo foram o emprego de hexano como solvente, na proporção de 40% em relação à massa de óleo, e sem o emprego de agitação no segundo estágio do resfriamento. Sob tais condições, obteve-se um óleo com teor de ácidos graxos poli-insaturados (PUFA de 64,3%, sendo observado um aumento no percentual dos ácidos graxos insaturados de aproximadamente 9,2% e uma redução de 13,4% dos saturados, em relação ao óleo branqueado de pescado.The process of winterization consists of fractional crystallization, in which the triglycerides of oils and fats are separate by the partial crystallization in the liquid phase. The objective of this work was to evaluate significant variables and the operational conditions in the solvent winterization process of the fish oil. The crude fish oil from fishery industries was bleached and used as raw material. During the winterization step, the bleached oil was cooled progressively from 30 ºC to 5 ºC in three phases. The solvent

  18. Telelegend Leo Karpin : ETV uus juhtkond teeb vaid lammutustööd / Leo Karpin ; interv. Verni Leivak

    Index Scriptorium Estoniae

    Karpin, Leo, 1946-2014

    2004-01-01

    Pea 40 aastat Eesti Televisioonis töötanud telerežissöör oma teletöölt lahkumise põhjustest. Lisaks kommentaar "ETV juhatuse esimees Ilmar Raag, miks tunnustatud telemees Leo Karpin ametist vabastati?"

  19. The LEO PCDU EVO - A Modular and Flexible Concept for Low to Medium Power LEO & Scientific Missions

    Directory of Open Access Journals (Sweden)

    Lapeña Emilio

    2017-01-01

    Market trend towards volume & mass reduction, plus new required capabilities (in particular End of Life Passivation and Launch Off to support multiple launch justify the need for a new LEO PCDU EVO generation. This paper will deal with a simple question with no immediate answer: how to save 20% PCDU mass and volume while keeping or improving existing performances.

  20. Design and Fabrication of DebriSat - A Representative LEO Satellite for Improvements to Standard Satellite Breakup Models

    Science.gov (United States)

    Clark, S.; Dietrich, A.; Fitz-Coy, N.; Weremeyer, M.; Liou, J.-C.

    2012-01-01

    This paper discusses the design and fabrication of DebriSat, a 50 kg satellite developed to be representative of a modern low Earth orbit satellite in terms of its components, materials used, and fabrication procedures. DebriSat will be the target of a future hypervelocity impact experiment to determine the physical characteristics of debris generated after an on-orbit collision of a modern LEO satellite. The major ground-based satellite impact experiment used by DoD and NASA in their development of satellite breakup models was SOCIT, conducted in 1992. The target used for that experiment was a Navy transit satellite (40 cm, 35 kg) fabricated in the 1960's. Modern satellites are very different in materials and construction techniques than those built 40 years ago. Therefore, there is a need to conduct a similar experiment using a modern target satellite to improve the fidelity of the satellite breakup models. To ensure that DebriSat is truly representative of typical LEO missions, a comprehensive study of historical LEO satellite designs and missions within the past 15 years for satellites ranging from 1 kg to 5000 kg was conducted. This study identified modern trends in hardware, material, and construction practices utilized in recent LEO missions. Although DebriSat is an engineering model, specific attention is placed on the quality, type, and quantity of the materials used in its fabrication to ensure the integrity of the outcome. With the exception of software, all other aspects of the satellite s design, fabrication, and assembly integration and testing will be as rigorous as that of an actual flight vehicle. For example, to simulate survivability of launch loads, DebriSat will be subjected to a vibration test. As well, the satellite will undergo thermal vacuum tests to verify that the components and overall systems meet typical environmental standards. Proper assembly and integration techniques will involve comprehensive joint analysis, including the precise

  1. Manual work in cold environments and its impact on selection of materials for protective gloves based on workplace observations.

    Science.gov (United States)

    Irzmańska, Emilia; Wójcik, Paulina; Adamus-Włodarczyk, Agnieszka

    2018-04-01

    This article presents a workplace observations on manual work in cold environments and its impact on the selection of materials for protective gloves. The workplace observations was conducted on 107 workers in 7 companies and involved measurements of the temperature of air and objects in the workplaces; in addition the type of surface and shape of the objects was determined. Laboratory tests were also carried out on 11 materials for protective gloves to be used in cold environments. Protective characteristics, including mechanical properties (wear, cut, tear, and puncture resistance), insulation properties (thermal resistance), functional parameters, and hygienic properties (resistance to surface wetting, material stiffness) were evaluated. Appropriate levels of performance and quality, corresponding to the protective and functional properties of the materials, were determined. Based on the results of manual work and laboratory tests, directions for the selection of materials for the construction of protective gloves were formulated with a view to improving work ergonomics. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. FRACIONAMENTO DE ÓLEOS DE CITROS UTILIZANDO FLUIDOS SUPERCRÍTICOS

    Directory of Open Access Journals (Sweden)

    Marisa MENDES

    1997-12-01

    Full Text Available O objetivo deste trabalho é o estudo sobre o fracionamento do óleo de laranja. Neste sentido, o limoneno e o linalol foram considerados os componentes-chaves do óleo de laranja, representando os terpenos e compostos oxigenados, respectivamente. Para modelar os dados de equilíbrio de fases foi usada a equação de estado de Peng-Robinson, juntamente com as regras de mistura de van der Waals, uni e biparamétrica, e de Panagiotopoulos e Reid. O uso desses modelos termodinâmicos permitiu determinar as condições de temperatura e pressão que levaram aos melhores valores do par seletividade-capacidade.The objective of this work is to study the fractionation of the citrus oils, especially orange oil. The orange oil is considered to be a mixture of two main components, limonene and linalool, which represent the terpenes and oxygenated group fractions, respectively. The Peng-Robinson equation of state using the van der Waals, with one or two parameters, and Panagiotopoulos and Reid mixing rules, were used to correlate and predict the binary and ternary high pressure phase equilibria of CO2 containing systems . The use of thermodynamic models to predict the phase equilibria allowed to establish the conditions of temperature and pressure, which led to the best results of selectivities and capacities of the extraction.

  3. A Parametric Study on Using Active Debris Removal for LEO Environment Remediation

    Science.gov (United States)

    2010-01-01

    Recent analyses on the instability of the orbital debris population in the low Earth orbit (LEO) region and the collision between Iridium 33 and Cosmos 2251 have reignited the interest in using active debris removal (ADR) to remediate the environment. There are; however, monumental technical, resource, operational, legal, and political challenges in making economically viable ADR a reality. Before a consensus on the need for ADR can be reached, a careful analysis of its effectiveness must be conducted. The goal is to demonstrate the need and feasibility of using ADR to better preserve the future environment and to guide its implementation to maximize the benefit-to-cost ratio. This paper describes a new sensitivity study on using ADR to stabilize the future LEO debris environment. The NASA long-term orbital debris evolutionary model, LEGEND, is used to quantify the effects of several key parameters, including target selection criteria/constraints and the starting epoch of ADR implementation. Additional analyses on potential ADR targets among the currently existing satellites and the benefits of collision avoidance maneuvers are also included.

  4. Material selection for the tool holder working under hard milling conditions using different multi criteria decision making methods

    International Nuclear Information System (INIS)

    Çalışkan, Halil; Kurşuncu, Bilal; Kurbanoğlu, Cahit; Güven, Şevki Yılmaz

    2013-01-01

    Highlights: ► The material selection problem for tool holders used in hard milling was solved. ► EXPROM2, TOPSIS and VIKOR methods were used for ranking the alternative materials. ► The weighting of criteria was performed by compromised weighting method. ► The best material for the tool holder was selected as Fe–5Cr–Mo–V aircraft steel. -- Abstract: Nowadays machining of materials in their hardened state, also called hard machining, is a challenge in production of tools and molds. It has some advantages such as lower process time and lower manufacturing cost when compared to conventional machining. In machining of hard workpiece materials, however, very high stresses act on the tool holder through the cutting tool. These stresses necessitate the tool holder to have some specific properties. Especially in hard milling, the tool holder should have high stiffness and should be able to dissipate the energy generated during interrupted cutting. Material cost of the tool holder is also important since lower costs provide a competitive advantage for manufacturers. The material selection for the tool holder should be conducted considering aforementioned requirements. To tackle the difficulty of the material selection with specific properties from a large number of alternatives, multi-criteria decision-making (MCDM) methods have been used. In this paper a decision model including extended PROMETHEE II (EXPROM2) (preference ranking organization method for enrichment evaluation), TOPSIS (technique for order performance by similarity to ideal solution) and VIKOR (VIšekriterijumsko KOmpromisno Rangiranje) methods were used for the selection of the best material for the tool holder used in hard milling. The criteria weighting was performed by compromised weighting method composed of AHP (analytic hierarchy process) and Entropy methods. The candidate materials were ranked by using these methods and the results obtained by each method were compared. It was confirmed

  5. Material selection for a constructed wetroof receiving pre-treated high strength domestic wastewater.

    Science.gov (United States)

    Zapater-Pereyra, M; van Dien, F; van Bruggen, J J A; Lens, P N L

    2013-01-01

    A constructed wetroof (CWR) is defined in this study as the combination of a green roof and a constructed wetland: a shallow wastewater treatment system placed on the roof of a building. The foremost challenge of such CWRs, and the main aim of this investigation, is the selection of an appropriate matrix capable of assuring the required hydraulic retention time, the long-term stability and the roof load-bearing capacity. Six substrata were subjected to water dynamics and destructive tests in two testing-tables. Among all the materials tested, the substratum configuration composed of sand, light expanded clay aggregates, biodegradable polylactic acid beads together with stabilization plates and a turf mat is capable of retaining the water for approximately 3.8 days and of providing stability (stabilization plates) and an immediate protection (turf mat) to the system. Based on those results, a full-scale CWR was built, which did not show any physical deterioration after 1 year of operation. Preliminary wastewater treatment results on the full-scale CWR suggest that it can highly remove main wastewater pollutants (e.g. chemical oxygen demand, PO4(3-)-P and NH4(+)-N). The results of these tests and practical design considerations of the CWR are discussed in this paper.

  6. Lesions to polar/orbital prefrontal cortex selectively impair reasoning about emotional material.

    Science.gov (United States)

    Goel, Vinod; Lam, Elaine; Smith, Kathleen W; Goel, Amit; Raymont, Vanessa; Krueger, Frank; Grafman, Jordan

    2017-05-01

    While it is widely accepted that lesions to orbital prefrontal cortex lead to emotion related disruptions and poor decision-making, there is very little patient data on this issue involving actual logical reasoning tasks. We tested patients with circumscribed, focal lesions largely confined to polar/orbital prefrontal cortex (BA 10 & 11) (N=17) on logical reasoning tasks involving neutral and emotional content, and compared their performance to that of an age and education-matched normal control group (N=22) and a posterior lesion control group (N=24). Our results revealed a significant group by content interaction driven by a selective impairment in the polar/orbital prefrontal cortex group compared to healthy normal controls and to the parietal patient group, in the emotional content reasoning trials. Subsequent analyses of congruent and incongruent reasoning trials indicated that this impairment was driven by the poor performance of patients with polar/orbital lesions in the incongruent trials. We conclude that the polar/orbital prefrontal cortex plays a critical role in filtering emotionally charged content from the material before it is passed on to the reasoning system in lateral/dorsal regions of prefrontal cortex. Where unfiltered content is passed to the reasoning engine, either as a result of pathology (as in the case of our patients) or as a result of individual differences, reasoning performance suffers. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Selective phase masking to reduce material saturation in holographic data storage systems

    Science.gov (United States)

    Phillips, Seth; Fair, Ivan

    2014-09-01

    Emerging networks and applications require enormous data storage. Holographic techniques promise high-capacity storage, given resolution of a few remaining technical issues. In this paper, we propose a technique to overcome one such issue: mitigation of large magnitude peaks in the stored image that cause material saturation resulting in readout errors. We consider the use of ternary data symbols, with modulation in amplitude and phase, and use a phase mask during the encoding stage to reduce the probability of large peaks arising in the stored Fourier domain image. An appropriate mask is selected from a predefined set of pseudo-random masks by computing the Fourier transform of the raw data array as well as the data array multiplied by each mask. The data array or masked array with the lowest Fourier domain peak values is recorded. On readout, the recorded array is multiplied by the mask used during recording to recover the original data array. Simulations are presented that demonstrate the benefit of this approach, and provide insight into the appropriate number of phase masks to use in high capacity holographic data storage systems.

  8. Why incoloy 800 was selected as tube material for the new steam generators of Doel 3

    International Nuclear Information System (INIS)

    Stubbe, J.; Wolters, F.; Somville, P.; De Ranter, K.

    1990-01-01

    Incoloy 800 or Inconel 690. This was the basic question for the SG of DOEL 3, to be replaced in 1993. A comparative evaluation was made, focused on the service behaviour, more particularly the corrosion resistance. It was concluded that both materials may be considered for SG replacement. They are indeed substantially superior to alloy 600, but none of them is really better than the other one: - they are both nearly completely immune to primary water stress corrosion cracking; - they are both susceptible to some types of attack from the secondary side. To the 690 credit are the globally better performances in the secondary side corrosion tests. However if the aggressive environments which are unlikely to occur at DOEL 3 are discarded, it appears that the margin between 690 and 800 is small. To the 800 credit is the favourable service experience except the secondary side wastage due to phosphate conditioning. 800 was finally selected not only because of favourable economic arguments, but also because of the important weight attributed to the service behaviour by the Belgian Utilities [fr

  9. Selection of nutrient used in biogenic healing agent for cementitious materials

    Science.gov (United States)

    Tziviloglou, Eirini; Wiktor, Virginie; Jonkers, Henk M.; Schlangen, Erik

    2017-06-01

    Biogenic self-healing cementitious materials target on the closure of micro-cracks with precipitated inorganic minerals originating from bacterial metabolic activity. Dormant bacterial spores and organic mineral compounds often constitute a biogenic healing agent. The current paper focuses on the investigation of the most appropriate organic carbon source to be used as component of a biogenic healing agent. It is of great importance to use an appropriate organic source, since it will firstly ensure an optimal bacterial performance in terms of metabolic activity, while it should secondly affect the least the properties of the cementitious matrix. The selection is made among three different organic compounds, namely calcium lactate, calcium acetate and sodium gluconate. The methodology that was used for the research was based on continuous and non-continuous oxygen consumption measurements of washed bacterial cultures and on compressive strength tests on mortar cubes. The oxygen consumption investigation revealed a preference for calcium lactate and acetate, but an indifferent behaviour for sodium gluconate. The compressive strength on mortar cubes with different amounts of either calcium lactate or acetate (up to 2.24% per cement weight) was not or it was positively affected when the compounds were dissolved in the mixing water. In fact, for calcium lactate the increase in compressive strength reached 8%, while for calcium acetate the maximum strength increase was 13.4%.

  10. Parallel algorithms for islanded microgrid with photovoltaic and energy storage systems planning optimization problem: Material selection and quantity demand optimization

    Science.gov (United States)

    Cao, Yang; Liu, Chun; Huang, Yuehui; Wang, Tieqiang; Sun, Chenjun; Yuan, Yue; Zhang, Xinsong; Wu, Shuyun

    2017-02-01

    With the development of roof photovoltaic power (PV) generation technology and the increasingly urgent need to improve supply reliability levels in remote areas, islanded microgrid with photovoltaic and energy storage systems (IMPE) is developing rapidly. The high costs of photovoltaic panel material and energy storage battery material have become the primary factors that hinder the development of IMPE. The advantages and disadvantages of different types of photovoltaic panel materials and energy storage battery materials are analyzed in this paper, and guidance is provided on material selection for IMPE planners. The time sequential simulation method is applied to optimize material demands of the IMPE. The model is solved by parallel algorithms that are provided by a commercial solver named CPLEX. Finally, to verify the model, an actual IMPE is selected as a case system. Simulation results on the case system indicate that the optimization model and corresponding algorithm is feasible. Guidance for material selection and quantity demand for IMPEs in remote areas is provided by this method.

  11. Group IV all-semiconductor spintronics. Materials aspects and optical spin selection rules

    Energy Technology Data Exchange (ETDEWEB)

    Sircar, Narayan

    2012-04-03

    particular, by including recent theory on spin-dependent selection rules for radiative transitions in bulk Si, we adapt an expression for the magnetic-field-induced photoluminescence polarization of direct band gap semiconductor materials of GaAs-type to Si. Measurements within an applied magnetic field of the degree of circular polarization of phononassisted photoluminescence of bulk Si for different doping are presented. Similar experiments on the photoluminescence of Ge quantum dot ensembles evidence a peculiarity for the spin-dependent selection rules for phononless radiative recombinations. We propose a connection between this finding and the confined character of electrons that are involved in the transitions. Furthermore, we try to optically inject and detect confined carrier spins in Ge quantum dot ensembles. For nonresonant excitation these efforts are unsuccessful, which we attribute to a hole spin relaxation that happens faster than the combined capture of the hole by the quantum dot and the radiative decay of the hole. Finally, we employ the p-type GeMn thin film layers presented in the first part of this work as spin-polarizing contacts for Si/SiGe-based light-emitting diodes with the aim to inject spin-polarized holes. Preliminary results of a circularly polarized electroluminescence of these devices propose the possibility of a successful hole spin injection near liquid helium temperatures.

  12. An Integrated Model of Material Supplier Selection and Order Allocation Using Fuzzy Extended AHP and Multiobjective Programming

    Directory of Open Access Journals (Sweden)

    Zhi Li

    2013-01-01

    Full Text Available This paper presents a supplier selection and order allocation (SSOA model to solve the problem of a multiperiod supplier selection and then order allocation in the environment of short product life cycle and frequent material purchasing, for example, fast fashion environment in apparel industry. At the first stage, with consideration of multiple decision criteria and the fuzziness of the data involved in deciding the preferences of multiple decision variables in supplier selection, the fuzzy extent analytic hierarchy process (FEAHP is adopted. In the second stage, supplier ranks are inputted into an order allocation model that aims at minimizing the risk of material purchasing and minimizing the total material purchasing costs using a dynamic programming approach, subject to constraints on deterministic customer demand and deterministic supplier capacity. Numerical examples are presented, and computational results are reported.

  13. POLIURETANOS BASEADOS EM ÓLEO DE MAMONA

    Directory of Open Access Journals (Sweden)

    Heliberto José Limberger

    2013-12-01

    Full Text Available Neste trabalho de revisão foram apresentadas as principais características do óleo de mamona e de poliuretanos (PUs obtidos a partir deste, descrevendo os métodos de síntese e obtenção empregados. Buscou-se reunir informações sobre novas tendências na área, bem como possíveis aplicações para este tipo de polímero considerando as diferentes propriedades que pode apresentar. PUs obtidos a partir de óleo de mamona podem ser aplicados nas áreas de construção civil, medicina, de materiais e de adesivos, apresentando a vantagem de serem oriundos de fonte renovável e muitas vezes serem biodegradáveis.

  14. Improved selectivity towards NO₂ of phthalocyanine-based chemosensors by means of original indigo/nanocarbons hybrid material.

    Science.gov (United States)

    Brunet, J; Pauly, A; Dubois, M; Rodriguez-Mendez, M L; Ndiaye, A L; Varenne, C; Guérin, K

    2014-09-01

    A new and original gas sensor-system dedicated to the selective monitoring of nitrogen dioxide in air and in the presence of ozone, has been successfully achieved. Because of its high sensitivity and its partial selectivity towards oxidizing pollutants (nitrogen dioxide and ozone), copper phthalocyanine-based chemoresistors are relevant. The selectivity towards nitrogen dioxide results from the implementation of a high efficient and selective ozone filter upstream the sensing device. Thus, a powdered indigo/nanocarbons hybrid material has been developed and investigated for such an application. If nanocarbonaceous material acts as a highly permeable matrix with a high specific surface area, immobilized indigo nanoparticles are involved into an ozonolysis reaction with ozone leading to the selective removal of this analytes from air sample. The filtering yields towards each gas have been experimentally quantified and establish the complete removal of ozone while having the concentration of nitrogen dioxide unchanged. Long-term gas exposures reveal the higher durability of hybrid material as compared to nanocarbons and indigo separately. Synthesis, characterizations by many complementary techniques and tests of hybrid filters are detailed. Results on sensor-system including CuPc-based chemoresistors and indigo/carbon nanotubes hybrid material as in-line filter are illustrated. Sensing performances will be especially discussed. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Mechanical property characterization and impact resistance of selected graphite/PEEK composite materials

    Science.gov (United States)

    Baker, Donald J.

    1994-01-01

    To use graphite polyetheretherketone (PEEK) material on highly curved surfaces requires that the material be drapable and easily conformable to the surface. This paper presents the mechanical property characterization and impact resistance results for laminates made from two types of graphite/PEEK materials that will conform to a curved surface. These laminates were made from two different material forms. These forms are: (1) a fabric where each yarn is a co-mingled Celion G30-500 3K graphite fiber and PEEK thermoplastic fiber; and (2) an interleaved material of Celion G30-500 3K graphite fabric interleaved with PEEK thermoplastic film. The experimental results from the fabric laminates are compared with results for laminates made from AS4/PEEK unidirectional tape. The results indicate that the tension and compression moduli for quasi-isotropic and orthotropic laminates made from fabric materials are at least 79 percent of the modulus of equivalent laminates made from tape material. The strength of fabric material laminates is at least 80 percent of laminates made from tape material. The evaluation of fabric material for shear stiffness indicates that a tape material laminate could be replaced by a fabric material laminate and still maintain 89 percent of the shear stiffness of the tape material laminate. The notched quasi-isotropic compression panel failure strength is 42 to 46 percent of the unnotched quasi-isotropic laminate strength. Damage area after impact with 20 ft-lbs of impact energy is larger for the co-mingled panels than for the interleaved panels. The inerleaved panels have less damage than panels made from tape material. Residual compression strength of quasi-isotropic panels after impact of 20 ft-lbs of energy varies between 33 percent of the undamaged quasi-isotropic material strength for the tape material and 38 percent of the undamaged quasi-isotropic material strength for the co-mingled fabric material.

  16. Analysis of Structural and Material Aspects of Selected Elements of a Hydropneumatic Suspension System in a Passenger Car

    Directory of Open Access Journals (Sweden)

    Konieczny Ł.

    2016-03-01

    Full Text Available The article addresses results of analyses of design solutions and materials commonly used in gas springs for hydropneumatic suspension systems. The authors have discussed main advantages resulting from application of such a design solution in passenger car suspension systems. Fundamental correlations defining the parameters characterising a gas spring with constant gas mass have been referred to. Also materials used in the manufacture of selected gas spring elements have been described

  17. A Young Star Cluster in the Leo a Galaxy

    Directory of Open Access Journals (Sweden)

    Stonkutė R.

    2015-09-01

    Full Text Available We report a serendipitous discovery of a star cluster in the dwarf irregular galaxy Leo A. Young age (~28 Myr and low mass (~510 M⊙ estimates are based on the isochrone fit assuming a metallicity derived for HII regions (Z = 0.0007. The color-magnitude diagrams of the stars, located in and around the cluster area, and the results of aperture photometry of the cluster itself are presented.

  18. Passive Optical Link Budget for LEO Space Surveillance

    Science.gov (United States)

    Wagner, P.; Hasenohr, T.; Hampf, D.; Sproll, F.; Humbert, L.; Rodmann, J.; Riede, W.

    The rising space debris population is becoming an increasing risk for space assets. Even objects with the size of 10mm can cause major damages to active spacecraft. Especially the orbits around 800km high are densely populated with space debris objects. To assess the risk of collisions with active satellites, the Earth orbits need to be surveyed permanently. Space debris laser ranging systems for example can deliver highly accurate positional data for precise orbit determination. Therefor a priori information about the objects coarse trajectory is needed. Such initial orbit information can be provided by wide angle optical sensors. The Institute of Technical Physics at the German Aerospace Center in Stuttgart runs an observatory to perform passive as well as laser optical measurements to LEO objects. In order to detect unknown objects, a wide-angle imaging system with a field of view in the range of 5° to 15° equipped with an astronomical CCD camera and a commercial off the shelf (COTS) lens was designed to continuously observe the night sky for LEO objects. This paper presents the passive optical link budget for observing LEO objects to show the benefits and limits of the physical performance of an optical surveillance system. A compact COTS system is able to detect objects with a couple of decimeters in size while a large aperture telescope can detect objects with diameters below 10cm. Additionally, data captured by a passive optical staring system with a 10 cm aperture was analyzed. It is shown that 90% of all objects with a radar cross section larger than 2m² are detected with such a system during twilight conditions. The smallest detected LEO object with this system has a size of 0.32m x 0.32m x 0.26m. These measurements are compared to the developed link budget which allows an estimation of the performance of larger systems.

  19. Can Telescopes Help Leo Satellites Dodge Most Lethal Impacts?

    Science.gov (United States)

    GUDIEL, ANDREA; Carroll, Joseph; Rowe, David

    2018-01-01

    Authors: Joseph Carroll and David RoweABSTRACT LEO objects are tracked by radar because it works day and night, in all weather. This fits military interest in potentially hostile objects. There is less interest in objects too small to be credible active threats. But accidental hypervelocity impact by even 5-10 mm objects can disable most LEO satellites. Such “cm-class” objects greatly outnumber objects of military interest, and will cause most accidental impact losses.Under good viewing conditions, a sunlit 5mm sphere with 0.15 albedo at 800 km altitude is a 19th magnitude object. A ground-based 0.5m telescope tracking it against a 20 mag/arcsec2 sky can see it in seconds, and provide 1 million such objects in LEO, nearly all debris fragments, mostly cm-class and at 600-1200 km altitude.Maintaining a ~million-item catalog requires a world-wide network of several dozen telescope sites with several telescopes at each site. Each telescope needs a mount capable of ~1,000,000 fast slews/year without wearing out.The paper discusses recent advances that make such a service far more feasible:1. Automated tasking and remote control of distributed telescope networks,2. Direct-drive mounts that can make millions of fast slews without wearing out,3. Telescope optics with low focal curvature that are in focus across large imagers,4. CMOS imagers with 95% peak QE and 1.5e- noise at 2E8 pix/sec readout rates,5. Methods for uncued detection of most lethal LEO debris (eg., >5 mm at 800 km),6. Initial orbit determination using 3 alt-az fixes made during the discovery pass,7. High-speed photometry to infer debris spin axis, to predict drag area changes,8. Better conjunction predictions using explicit modeling of drag area variations.

  20. LEOPACK The integrated services communications system based on LEO satellites

    Science.gov (United States)

    Negoda, A.; Bunin, S.; Bushuev, E.; Dranovsky, V.

    LEOPACK is yet another LEO satellite project which provides global integrated services for 'business' communications. It utilizes packet rather then circuit switching in both terrestrial and satellite chains as well as cellular approach for frequencies use. Original multiple access protocols and decentralized network control make it possible to organize regionally or logically independent and world-wide networks. Relatively small number of satellites (28) provides virtually global network coverage.

  1. An objective approach for Burkholderia pseudomallei strain selection as challenge material for medical countermeasures efficacy testing

    Directory of Open Access Journals (Sweden)

    Kristopher E. Van Zandt

    2012-09-01

    Full Text Available Burkholderia pseudomallei is the causative agent of melioidosis, a rare disease of biodefense concern with high mortality and extreme difficulty in treatment. No human vaccines are available that protect against B. pseudomallei infection, and with the current limitations of antibiotic treatment, the development of new preventative and therapeutic interventions is crucial. Although clinical trials could be used to test the efficacy of new medical countermeasures (MCMs, the high mortality rates associated with melioidosis raises significant ethical issues concerning treating individuals with new compounds with unknown efficacies. The US Food and Drug Administration (FDA has formulated a set of guidelines for the licensure of new MCMs to treat diseases in which it would be unethical to test the efficacy of these drugs in humans. The FDA Animal Rule 21 CFR 314 calls for consistent, well-characterized B. pseudomallei strains to be used as challenge material in animal models. In order to facilitate the efficacy testing of new MCMs for melioidosis using animal models, we intend to develop a well-characterized panel of strains for use. This panel will comprise of strains that were isolated from human cases, have a low passage history, are virulent in animal models, and are well characterized phenotypically and genotypically. We have reviewed published and unpublished data on various B. pseudomallei strains to establish an objective method for selecting the strains to be included in the panel of B. pseudomallei strains with attention to five categories: animal infection models, genetic characterization, clinical and passage history, and availability of the strain to the research community. We identified 109 strains with data in at least one of the five categories, scored each strain based on the gathered data and identified 6 strains as candidate for a B. pseudomallei strain panel.

  2. An objective approach for Burkholderia pseudomallei strain selection as challenge material for medical countermeasures efficacy testing.

    Science.gov (United States)

    Van Zandt, Kristopher E; Tuanyok, Apichai; Keim, Paul S; Warren, Richard L; Gelhaus, H Carl

    2012-01-01

    Burkholderia pseudomallei is the causative agent of melioidosis, a rare disease of biodefense concern with high mortality and extreme difficulty in treatment. No human vaccines are available that protect against B. pseudomallei infection, and with the current limitations of antibiotic treatment, the development of new preventative and therapeutic interventions is crucial. Although clinical trials could be used to test the efficacy of new medical countermeasures (MCMs), the high mortality rates associated with melioidosis raises significant ethical issues concerning treating individuals with new compounds with unknown efficacies. The US Food and Drug Administration (FDA) has formulated a set of guidelines for the licensure of new MCMs to treat diseases in which it would be unethical to test the efficacy of these drugs in humans. The FDA "Animal Rule" 21 CFR 314 calls for consistent, well-characterized B. pseudomallei strains to be used as challenge material in animal models. In order to facilitate the efficacy testing of new MCMs for melioidosis using animal models, we intend to develop a well-characterized panel of strains for use. This panel will comprise of strains that were isolated from human cases, have a low passage history, are virulent in animal models, and are well-characterized phenotypically and genotypically. We have reviewed published and unpublished data on various B. pseudomallei strains to establish an objective method for selecting the strains to be included in the panel of B. pseudomallei strains with attention to five categories: animal infection models, genetic characterization, clinical and passage history, and availability of the strain to the research community. We identified 109 strains with data in at least one of the five categories, scored each strain based on the gathered data and identified six strains as candidate for a B. pseudomallei strain panel.

  3. Digital Materials - Evaluation of the Possibilities of using Selected Hyperelastic Models to Describe Constitutive Relations

    Science.gov (United States)

    Mańkowski, J.; Lipnicki, J.

    2017-08-01

    The authors tried to identify the parameters of numerical models of digital materials, which are a kind of composite resulting from the manufacture of the product in 3D printers. With the arrangement of several heads of the printer, the new material can result from mixing of materials with radically different properties, during the process of producing single layer of the product. The new material has properties dependent on the base materials properties and their proportions. Digital materials tensile characteristics are often non-linear and qualify to be described by hyperelastic materials models. The identification was conducted based on the results of tensile tests models, its various degrees coefficients of the polynomials to various degrees coefficients of the polynomials. The Drucker's stability criterion was also examined. Fourteen different materials were analyzed.

  4. Digital Materials – Evaluation of the Possibilities of using Selected Hyperelastic Models to Describe Constitutive Relations

    Directory of Open Access Journals (Sweden)

    Mańkowski J.

    2017-08-01

    Full Text Available The authors tried to identify the parameters of numerical models of digital materials, which are a kind of composite resulting from the manufacture of the product in 3D printers. With the arrangement of several heads of the printer, the new material can result from mixing of materials with radically different properties, during the process of producing single layer of the product. The new material has properties dependent on the base materials properties and their proportions. Digital materials tensile characteristics are often non-linear and qualify to be described by hyperelastic materials models. The identification was conducted based on the results of tensile tests models, its various degrees coefficients of the polynomials to various degrees coefficients of the polynomials. The Drucker’s stability criterion was also examined. Fourteen different materials were analyzed.

  5. Investigação da presença de óleo essencial em Eucalyptus smithii R.T. Baker por meio da anatomia de seu lenho e casca.

    Directory of Open Access Journals (Sweden)

    Fernando José Fabrowski

    2010-08-01

    Full Text Available O material utilizado no presente estudo foi proveniente de 15 árvores de Eucalyptus smithii R.T. Baker cultivadas no município de Colombo - PR, em campo experimental da Embrapa Florestas, plantadas em 1988. Caracterizou-se anatomicamente o lenho e a casca por meio de lâminas preparadas no Laboratório de Anatomia e Identificação de Madeiras do IPT e Laboratório de Anatomia da Madeira, do Centro de Ciências Florestais e da Madeira, da Universidade Federal do Paraná. Para a extração do óleo essencial, a madeira foi transformada em serragem e a casca desfibrada manualmente. Para a determinação do rendimento e análise do óleo essencial, foram efetuadas destilações conforme ABNT no Laboratório de Fitoquímica do Departamento de Farmácia da Universidade Federal do Paraná. Os rendimentos do óleo essencial foram dados em volume (ml de óleo essencial por massa (g de material. O Eucalyptus smithii apresenta estrutura anatômica homogênea do lenho e da casca. Na casca, observou-se a presença de cavidades secretoras; no entanto, no lenho, não foi encontrada nenhuma estrutura semelhante, apenas bolsas de quino, sendo desprezível a quantidade de óleo essencial presente na madeira. O óleo essencial da casca apresentou características físico-químicas fora das especificações para óleos essenciais de eucaliptos ricos em 1,8-cineol, não sendo economicamente viável para a exploração desse componente.

  6. Effect of substrate material selection on polychromatic integral diffraction efficiency for multilayer diffractive optics in oblique incident situation

    Science.gov (United States)

    Zhang, Bo; Cui, Qingfeng; Piao, Mingxu

    2018-05-01

    The effect of substrate material selection for multilayer diffractive optical elements (MLDOEs) on polychromatic integral diffraction efficiency (PIDE) is studied in the oblique incident situation. A mathematical model of substrate material selection is proposed to obtain the high PIDE with large incident angle. The extended expression of the microstructure heights with consideration of incident angle is deduced to calculate the PIDE difference Δ η bar(λ) for different substrate material combinations. The smaller value of Δ η bar(λ) indicates the more optimal substrate material combination in a wide incident angle range. Based on the deduced mathematical model, different MLDOEs are analyzed in visible and infrared wavebands. The results show that the three-layer DOEs can be applied in larger incident angle situation than the double-layer DOEs in visible waveband. When the two substrate materials are the same, polycarbonate (PC) is more reasonable than poly(methyl methacrylate) (PMMA) as the middle filling optical material for the three-layer DOEs. In the infrared waveband, the PIDE decreases in the LWIR are obviously smaller than that in the MWIR for the same substrate material combination, and the PIDE cannot be calculated when the incident angle larger than critical angle. The analysis results can be used to guide the hybrid optical system design with MLDOEs.

  7. Engaging degradation mechanisms of materials in a tourney. An investigation into the philosophy of material selection as a mitigating measure and strategy

    OpenAIRE

    Narasimhavarman, Arasilangkumari

    2014-01-01

    Master's thesis in Offshore Technology The aim of this project is to compare some important factors such as safety and environmental aspects, life cycle costing, reliability, availability and fabrication for selecting materials for flowlines for comparative study between carbon steel as a current practice with respect to various corrosion resistance alloys as an alternatives. In order to do that it is necessary to address all possible degradation mechanisms and the conditions that intensif...

  8. Evaluating the environmental criticality of massive objects in LEO for debris mitigation and remediation

    Science.gov (United States)

    Pardini, Carmen; Anselmo, Luciano

    2018-04-01

    Approximately 95% of the mass in Earth orbit is currently concentrated in about 6700 intact objects, of which nearly 80% are abandoned and more than 90% cannot be maneuvered. The intact objects abandoned in low Earth orbit (LEO) above 650 km, i.e. with an average residual lifetime of more than 25 years, represent the main potential mass reservoir for the generation of new detrimental orbital debris in case of mutual collisions with the existing debris environment, taking into account that an 800 g impactor may be sufficient, in principle, to shatter a 1000 kg spacecraft or rocket stage. Since the 1980's, several mitigation measures were promoted and agreed at the international level in order to prevent the occurrence of new breakups in space and put under control the accumulation of mass abandoned in orbit, but unfortunately the level of compliance with such guidelines, requirements or standards is still far from satisfactory. Moreover, the appearance on the scene of space activity of new private and government actors from a growing number of countries makes the proper management of the circumterrestrial space a task of increasing complexity, taking also into account the rapid emerging of new potential applications, disrupting technologies and operational approaches quite different from the past. In this rapidly evolving environment, it might be useful to have a simple and flexible instrument for evaluating the potential criticality for the environment of massive objects placed or abandoned in LEO. With this goal, in the last few years, a particular effort was devoted to the development of various "criticality indexes", then applied for evaluating many families of rocket bodies and selected spacecraft. In this paper, with the underlining ambition to be simple, intuitive and relevant, from an environmental point of view, a couple of the most complete indexes were coherently applied in order to assess the potential criticality of the most massive objects abandoned in

  9. Cholangiocarcinoma of intrahepatic bile ducts with disseminated metastases in an African lion (Panthera leo).

    Science.gov (United States)

    Lepri, Elvio; Sforna, Monica; Brachelente, Chiara; Chiara, Brachelente; Vitellozzi, Giovanni; Giovanni, Vitellozzi

    2013-06-01

    A cholangiocarcinoma is reported in an 18-yr-old, female African lion (Panthera leo). The primary tumor consisted of multifocal to coalescing, hepatic, white-yellow masses distributed throughout the liver lobes. Metastases were present in regional lymph nodes, peritoneal surface, and lungs. Histologically, the tumor was characterized by a tubular pattern with alcian- and periodic acid-Schiff-positive secretory material in cystic spaces. The neoplastic cells were positive to broad-spectrum cytokeratins. Histochemical and immunohistochemical stains were consistent with bile duct carcinoma. Biliary tumors arising from the gallbladder have been reported in lions. However, to the authors' knowledge, this is the first case of intrahepatic bile duct carcinoma reported in an African lion.

  10. Hinnangud võtmeesinejatele / Leo Voogt ; inglise keelest tõlkinud Kristina Pai

    Index Scriptorium Estoniae

    Voogt, Leo

    2012-01-01

    Euroopa teadusraamatukogude organisatsiooni LIBER-i tegevdirektori Leo Voogti seisukohad Tartus 27.-30. juunil 2012 peetud konverentsi ettekandjate kohta, lisaks konverentsi ankeetides tagasisidena kajastunu

  11. Archeointensities in Greece during the Neolithic period: New insights into material selection and secular variation curve

    Science.gov (United States)

    Fanjat, G.; Aidona, E.; Kondopoulou, D.; Camps, P.; Rathossi, C.; Poidras, T.

    2013-02-01

    Numerous archeomagnetic studies have provided high quality data for both the direction and the intensity of the geomagnetic field, essentially in Europe for the last 10 millennia. In particular, Greece supplies a lot of archeological materials due to its impressive cultural heritage and volcanic activity, so that numerous data have been obtained from burnt clays or historical lava flows. The most recent Greek secular variation curves are available for the last 8 millennia for the intensity and the last 6 millennia for the direction. Nevertheless, the coverage still presents several gaps for periods older than 2500 BC. In an effort to complete the Greek curve and extend it to older times, we present the archeointensity results from three Neolithic settlements in Northern Greece. The samples are of two different natures: burnt structures from Avgi (5250 ± 150 BC) and Vasili (4800 ± 200 BC), as well as ceramics from Dikili Tash (4830 ± 80 BC) and Vasili (4750 ± 250 BC). The samples have been subjected to standard rock magnetic analyses in order to estimate the thermal stability and the domain state of the magnetic carriers before archeointensity measurements. Surprisingly, very few ceramic samples provided reliable archeointensities whereas samples from burnt structures presented a very good success rate. Complementary studies showed that a detailed examination of the matrix color, following archeological information and classification standards can be a decisive test for pre-selection of sherds. In spite of these unsuccessful measurements from ceramics, we obtained an intensity value of 73.5 ± 1.1 μT for Dikili Tash, a higher value than the other data obtained in the same area, during the same period. However we do not have evidences for a technical artefact during the experiment. The burnt structures yielded two reliable archeointensities of 36.1 ± 1.8 μT and 46.6 ± 3.4 μT for Avgi and Vasili, respectively. Finally, we achieved a new archeomagnetic dating

  12. Chemistry {ampersand} Materials Science progress report summary of selected research and development topics, FY97

    Energy Technology Data Exchange (ETDEWEB)

    Newkirk, L.

    1997-12-01

    This report contains summaries of research performed in the Chemistry and Materials Science division. Topics include Metals and Ceramics, High Explosives, Organic Synthesis, Instrument Development, and other topics.

  13. Selective versus routine patch metal allergy testing to select bar material for the Nuss procedure in 932 patients over 10years.

    Science.gov (United States)

    Obermeyer, Robert J; Gaffar, Sheema; Kelly, Robert E; Kuhn, M Ann; Frantz, Frazier W; McGuire, Margaret M; Paulson, James F; Kelly, Cynthia S

    2018-02-01

    The aim of the study was to determine the role of patch metal allergy testing to select bar material for the Nuss procedure. An IRB-approved (11-04-WC-0098) single institution retrospective, cohort study comparing selective versus routine patch metal allergy testing to select stainless steel or titanium bars for Nuss repair was performed. In Cohort A (9/2004-1/2011), selective patch testing was performed based on clinical risk factors. In Cohort B (2/2011-9/2014), all patients were patch tested. The cohorts were compared for incidence of bar allergy and resultant premature bar loss. Risk factors for stainless steel allergy or positive patch test were evaluated. Cohort A had 628 patients with 63 (10.0%) selected for patch testing, while all 304 patients in Cohort B were tested. Over 10years, 15 (1.8%) of the 842 stainless steel Nuss repairs resulted in a bar allergy, and 5 had a negative preoperative patch test. The incidence of stainless steel bar allergy (1.8% vs 1.7%, p=0.57) and resultant bar loss (0.5% vs 1.3%, p=0.23) was not statistically different between cohorts. An allergic reaction to a stainless steel bar or a positive patch test was more common in females (OR=2.3, pbar allergies occur at a low incidence with either routine or selective patch metal allergy testing. If selective testing is performed, it is advisable in females and patients with a personal or family history of metal sensitivity. A negative preoperative patch metal allergy test does not preclude the possibility of a postoperative stainless steel bar allergy. Level III Treatment Study and Study of Diagnostic Test. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. A coordination polymer based magnetic adsorbent material for hemoglobin isolation from human whole blood, highly selective and recoverable

    Science.gov (United States)

    Zhang, Xiaoxing; Tan, Jipeng; Xu, Xinxin; Shi, Fanian; Li, Guanglu; Yang, Yiqiao

    2017-09-01

    A composite material has been obtained successfully through the loading of nanoscale coordination polymer on magnetic Fe3O4@SiO2 core-shell particle. In this composite material, coordination polymer nanoparticles distribute uniformly on Fe3O4@SiO2 and these two components are "tied" together firmly with chemical bonds. Adsorption experiments suggest this composite material exhibits very excellent selectivity to hemoglobin. But under the same condition, its adsorption to bovine serum albumin can almost be ignored. This selectivity can be attributed to the existence of hydrophobic interactions between coordination polymer nanoparticle and hemoglobin. For composite material, the hemoglobin adsorption process follows Langmuir model perfectly with high speed. The adsorbed hemoglobin can be eluted easily by sodium dodecyl sulfate stripping reagent with structure and biological activity of hemoglobin keeps well. The composite material was also employed to separate hemoglobin from human whole blood, which receives a very satisfactory result. Furthermore, magnetic measurement reveals ferromagnetic character of this composite material with magnetization saturation 3.56 emu g-1 and this guarantees its excellent magnetic separation performance from the treated solution.

  15. Structural in situ study of the thermal behavior of manganese dioxide materials: toward selected electrode materials for supercapacitors.

    Science.gov (United States)

    Ghodbane, Ouassim; Pascal, Jean-Louis; Fraisse, Bernard; Favier, Frédéric

    2010-12-01

    The thermal behavior of a series of MnO2 materials was investigated toward MnO2 microstructures under inert atmospheres. The byproduct formed during MnO2 heat treatments from the room temperature to 800 °C were characterized by in situ X-ray diffraction analyses. It was found that annealing spinel and ramsdellite phases caused the formation of MnO2 pyrolusite at 200 °C, Mn2O3, at 400 °C, and then Mn3O4 at higher temperatures. In the case of cryptomelane and birnessite phases, the heating process resulted in the formation of K0.51Mn0.93O2 at 600 °C, while Mn3O4 was also formed and still present up to 800 °C. Heat-treating Ni-todorokite and OMS-5 up to about 450 °C led to the formation of NiMn2O4 and NaxMnO2, respectively, and again Mn3O4 at higher temperatures. All of these structural transformations were correlated to resulting weight losses of MnO2 powders, measured by thermogravimetric analyses, during the heating process. Cyclic voltammetry measurements were performed in the presence of 0.5 M K2SO4 aqueous solution for annealed cryptomelane, K0.51Mn0.93O2, and Mn3O4-based electrodes. It was found that MnO2 cryptomelane is electrochemically stable upon heating. The long-term charge/discharge voltammetric cycling revealed that the specific capacitance of Mn3O4-based electrode is significantly improved from 14 F·g(-1) (after 20 cycles) to 123 F·g(-1) (after 500 cycles).

  16. Capacidade antioxidante total de óleos vegetais comestíveis: determinantes químicos e sua relação com a qualidade dos óleos Total antioxidant capacity of edible vegetable oils: chemical determinants and associations with oil quality

    Directory of Open Access Journals (Sweden)

    Vanessa Naciuk Castelo-Branco

    2011-02-01

    Full Text Available A capacidade antioxidante total de óleos vegetais comestíveis é determinada por sua composição físico-química e pode estar associada a atributos de qualidade dos óleos, especialmente a sua bioatividade e possivelmente a sua estabilidade oxidativa. Este artigo apresenta os fundamentos dos ensaios de capacidade antioxidante total e avalia criticamente os ensaios aplicáveis na análise de óleos e os pontos críticos nas aplicações dos ensaios para a análise dessas amostras. Discute-se o potencial papel dos componentes químicos dos óleos comestíveis como determinantes da capacidade antioxidante total, assim como a possível relação da capacidade antioxidante com a bioatividade e a estabilidade oxidativa dos óleos. Finalmente, discutem-se evidências de que, caso seja sistematicamente investigado em trabalhos experimentais futuros, o uso de ensaios de capacidade antioxidante total na análise de óleos vegetais pode contribuir para integrar o conhecimento da composição química com a bioatividade e possivelmente com a estabilidade de óleos vegetais específicos. Dessa forma, os ensaios de capacidade antioxidante apresentam potencial para aplicação no controle da qualidade integral de óleos comestíveis.The total antioxidant capacity of edible vegetable oils is determined by their physical-chemical composition and might be associated with their quality attributes, especially with bioactivity and possibly with oxidative stability. The current review presents the fundamentals of total antioxidant capacity assays and critically evaluates the assays applicable to the analysis of oils. The role of the chemical components of edible oils as determinants of total antioxidant capacity is discussed, as well as the potential associations between antioxidant capacity and bioactivity or oxidative stability of the selected oils. Finally, we discuss evidences that, if systematically addressed in future experimental work, the application of

  17. Selection and Basic Properties of the Buffer Material for High-Level Radioactive Waste Repository in China

    Institute of Scientific and Technical Information of China (English)

    WEN Zhijian

    2008-01-01

    Radioactive wastes arising from a wide range of human activities are in many different physical and chemical forms, contaminated with varying radioactivity. Their common features are the potential hazard associated with their radioactivity and the need to manage them in such a way as to protect the human environment. The geological disposal is regarded as the most reasonable and effective way to safely disposing high-level radioactive wastes in the world. The conceptual model of geological disposal in China is based on a multi-barrier system that combines an isolating geological environment with an engineered barrier system. The buffer is one of the main engineered barriers for HLW repository. It is expected to maintain its low water permeability, self-sealing property, radio nuclides adsorption and retardation properties, thermal conductivity, chemical buffering property,canister supporting property, and stress buffering property over a long period of time. Bentonite is selected as the main content of buffer material that can satisfy the above requirements. The Gaomiaozi deposit is selected as the candidate supplier for China's buffer material of high level radioactive waste repository. This paper presents the geological features of the GMZ deposit and basic properties of the GMZ Na-bentonite. It is a super-large deposit with a high content of montmorillonite (about 75%), and GMZ-1, which is Na-bentonite produced from GMZ deposit is selected as the reference material for China's buffer material study.

  18. Hemi-ordered nanoporous carbon electrode material for highly selective determination of nitrite in physiological and environmental systems

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Shenghai; Wu, Hongmin; Wu, Ying; Shi, Hongyan; Feng, Xun; Jiang, Shang; Chen, Jian; Song, Wenbo, E-mail: wbsong@jlu.edu.cn

    2014-08-01

    Hemi-ordered nanoporous carbon (HONC) was obtained from a mesoporous silica template through a nano-replication method using furfuryl alcohol as the carbon source. The structure and morphology of HONC were characterized and analyzed in detail by X-ray diffraction, N{sub 2}-sorption, Raman spectroscopy and transmission electron microscopy. HONC was then demonstrated as active electrode material for selective determination of nitrite in either physiological or environmental system. Well separated oxidation peaks of ascorbic acid, dopamine, uric acid and nitrite were observed in physiological system, and simultaneous discrimination of catechol, hydroquinone, resorcinol and nitrite in environmental system was also accomplished. Distinctly improved performances for selective determination of nitrite (such as significantly fast and sensitive current response with especially high selectivity) coexisted with ascorbic acid, dopamine and uric acid in the physiological system, as well as with catechol, hydroquinone and resorcinol in the environmental system were achieved at HONC electrode material. The excellent discriminating ability and high selectivity for NO{sub 2}{sup −} determination were ascribed to the good electronic conductivity, unique hemi-ordered porous structure, large surface area and large number of edge plane defect sites contained on the surface of nanopore walls of HONC. Results in this work demonstrated that HONC is one of the promising catalytic electrode materials for nitrite sensor fabrication. - Highlights: • Hemi-ordered nanoporous carbon as an active electrode material • Good discriminating ability towards NO{sub 2}{sup −} from physiological or environmental system • Highly selective determination of nitrite with fast and sensitive current response.

  19. Simulation of the space debris environment in LEO using a simplified approach

    Science.gov (United States)

    Kebschull, Christopher; Scheidemann, Philipp; Hesselbach, Sebastian; Radtke, Jonas; Braun, Vitali; Krag, H.; Stoll, Enrico

    2017-01-01

    -based simulation Long-term Utility for Collision Analysis (LUCA), which is also being developed at the IRAS. The evolution of the population in LEO for a 200 years time span is shown and compared for both approaches using step sizes of 1 year. For selected objects in LEO the collision flux values are shown. Additionally a value called environmental criticality (EC) is derived. It describes the effect an object can have on the space debris environment. In conclusion the field of application for such a fast model is shown.

  20. Applications of Piezoelectric Materials in Structural Health Monitoring and Repair: Selected Research Examples.

    Science.gov (United States)

    Duan, Wen Hui; Wang, Quan; Quek, Ser Tong

    2010-12-06

    The paper reviews the recent applications of piezoelectric materials in structural health monitoring and repair conducted by the authors. First, commonly used piezoelectric materials in structural health monitoring and structure repair are introduced. The analysis of plain piezoelectric sensors and actuators and interdigital transducer and their applications in beam, plate and pipe structures for damage detection are reviewed in detail. Second, an overview is presented on the recent advances in the applications of piezoelectric materials in structural repair. In addition, the basic principle and the current development of the technique are examined.

  1. First wall and blanket module safety enhancement by material selection and design decision

    International Nuclear Information System (INIS)

    Merrill, B.J.

    1980-01-01

    A thermal/mechanical study has been performed which illustrates the behavior of a fusion reactor first wall and blanket module during a loss of coolant flow event. The relative safety advantages of various material and design options were determined. A generalized first wall-blanket concept was developed to provide the flexibility to vary the structural material (stainless steel vs titanium), coolant (helium vs water), and breeder material (liquid lithium vs solid lithium aluminate). In addition, independent vs common first wall-blanket cooling and coupled adjacent module cooling design options were included in the study. The comparative analyses were performed using a modified thermal analysis code to handle phase change problems

  2. Applications of Piezoelectric Materials in Structural Health Monitoring and Repair: Selected Research Examples

    Directory of Open Access Journals (Sweden)

    Ser Tong Quek

    2010-12-01

    Full Text Available The paper reviews the recent applications of piezoelectric materials in structural health monitoring and repair conducted by the authors. First, commonly used piezoelectric materials in structural health monitoring and structure repair are introduced. The analysis of plain piezoelectric sensors and actuators and interdigital transducer and their applications in beam, plate and pipe structures for damage detection are reviewed in detail. Second, an overview is presented on the recent advances in the applications of piezoelectric materials in structural repair. In addition, the basic principle and the current development of the technique are examined.

  3. Amorphous infinite coordination polymer microparticles: a new class of selective hydrogen storage materials

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, You-Moon; Heo, Jungseok; Mirkin, Chad A [Department of Chemistry, International Institute for Nanotechnology, Northwestern University, 2145 Sheridan Road, Evanston, IL (United States); Armatas, Gerasimos S [Department of Chemistry, Northwestern University, Evanston, IL (United States); Kanatzidis, Mercouri G [Materials Science Division, Argonne National Laboratory, Argonne, IL (United States)

    2008-06-04

    A new class of micrometer-sized amorphous infinite coordination particles is selectively prepared from the coordination chemistry of a metallo-salen building block and Zn{sup 2+} ions. The particles show moderately high H{sub 2} uptake and almost no N{sub 2} adsorption, even though they are amorphous and do not have the well-defined channels typically used to explain such selectivity in metal-organic framework systems. (Abstract Copyright [2008], Wiley Periodicals, Inc.)

  4. Down Select Report of Chemical Hydrogen Storage Materials, Catalysts, and Spent Fuel Regeneration Processes

    Energy Technology Data Exchange (ETDEWEB)

    Ott, Kevin; Linehan, Sue; Lipiecki, Frank; Aardahl, Christopher L.

    2008-08-24

    The DOE Hydrogen Storage Program is focused on identifying and developing viable hydrogen storage systems for onboard vehicular applications. The program funds exploratory research directed at identifying new materials and concepts for storage of hydrogen having high gravimetric and volumetric capacities that have the potential to meet long term technical targets for onboard storage. Approaches currently being examined are reversible metal hydride storage materials, reversible hydrogen sorption systems, and chemical hydrogen storage systems. The latter approach concerns materials that release hydrogen in endothermic or exothermic chemical bond-breaking processes. To regenerate the spent fuels arising from hydrogen release from such materials, chemical processes must be employed. These chemical regeneration processes are envisioned to occur offboard the vehicle.

  5. the art of preview in appropriate teaching/learning material selection

    African Journals Online (AJOL)

    USER

    Abstract. This study recognised the importance of print materials and texts in effective and ... As previewers, they ought to look into the external and internal .... detailed information, the reading techniques will change to suit the purposes.

  6. Assessment of the quality of test results from selected civil engineering material testing laboratories in Tanzania

    CSIR Research Space (South Africa)

    Mbawala, SJ

    2017-12-01

    Full Text Available Civil and geotechnical engineering material testing laboratories are expected to produce accurate and reliable test results. However, the ability of laboratories to produce accurate and reliable test results depends on many factors, among others...

  7. Selection of Easily Accessible PCR- and Bio-Compatible Materials for Microfluidic Chips

    KAUST Repository

    Xiao, Kang

    2013-10-30

    Conventional fabrication of microfluidic chip is a complicated and time, effort and material consuming process. Consequently, due to high expenses, it has poor applicability for performing mass biological analysis by microfluidics. In this study, we repor

  8. Selection of Easily Accessible PCR- and Bio-Compatible Materials for Microfluidic Chips

    KAUST Repository

    Xiao, Kang; Kodzius, Rimantas; Wu, Jinbo

    2013-01-01

    Conventional fabrication of microfluidic chip is a complicated and time, effort and material consuming process. Consequently, due to high expenses, it has poor applicability for performing mass biological analysis by microfluidics. In this study, we

  9. Material and Energy Flows Associated with Select Metals in GREET 2. Molybdenum, Platinum, Zinc, Nickel, Silicon

    Energy Technology Data Exchange (ETDEWEB)

    Benavides, Pahola T. [Argonne National Lab. (ANL), Argonne, IL (United States); Dai, Qiang [Argonne National Lab. (ANL), Argonne, IL (United States); Sullivan, John L. [Argonne National Lab. (ANL), Argonne, IL (United States); Kelly, Jarod C. [Argonne National Lab. (ANL), Argonne, IL (United States); Dunn, Jennifer B. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-09-01

    In this work, we analyzed the material and energy consumption from mining to production of molybdenum, platinum, zinc, and nickel. We also analyzed the production of solar- and semiconductor-grade silicon. We described new additions to and expansions of the data in GREET 2. In some cases, we used operating permits and sustainability reports to estimate the material and energy flows for molybdenum, platinum, and nickel, while for zinc and silicon we relied on information provided in the literature.

  10. Selection and authentication of botanical materials for the development of analytical methods.

    Science.gov (United States)

    Applequist, Wendy L; Miller, James S

    2013-05-01

    Herbal products, for example botanical dietary supplements, are widely used. Analytical methods are needed to ensure that botanical ingredients used in commercial products are correctly identified and that research materials are of adequate quality and are sufficiently characterized to enable research to be interpreted and replicated. Adulteration of botanical material in commerce is common for some species. The development of analytical methods for specific botanicals, and accurate reporting of research results, depend critically on correct identification of test materials. Conscious efforts must therefore be made to ensure that the botanical identity of test materials is rigorously confirmed and documented through preservation of vouchers, and that their geographic origin and handling are appropriate. Use of material with an associated herbarium voucher that can be botanically identified is always ideal. Indirect methods of authenticating bulk material in commerce, for example use of organoleptic, anatomical, chemical, or molecular characteristics, are not always acceptable for the chemist's purposes. Familiarity with botanical and pharmacognostic literature is necessary to determine what potential adulterants exist and how they may be distinguished.

  11. [Study on material base of Carthamus tinctorius with antioxidant effect based on selective knock-out].

    Science.gov (United States)

    Wang, Lin-Yan; Tang, Yu-Ping; Liu, Xin; Ge, Ya-Hui; Li, Shu-Jiao; Shang, Er-Xin; Duan, Jin-Ao

    2014-04-01

    To establish a method for studying efficacious materials of traditional Chinese medicines from an overall perspective. Carthamus tinctorius was taken the example. Its major components were depleted by preparing liquid chromatography. Afterwards, the samples with major components depleted were evaluated for their antioxidant effect, so as to compare and analyze the major efficacious materials of C. tinctorius with antioxidant activity and the contributions. Seven major components were depleted from C. tinctorius samples, and six of them were identified with MS data and control comparison. After all of the samples including depleted materials are compared and evaluated for their antioxidant effect, the findings showed that hydroxysafflor yellow A, anhydrosafflor yellow B and 6-hydroxykaempferol-3, 6-di-O-glucoside-7-O-glucuronide were the major efficacious materials. This study explored a novel and effective method for studying efficacious materials of traditional Chinese medicines. Through this method, we could explain the direct and indirect contributions of different components to the efficacy of traditional Chinese medicines, and make the efficacious material expression of traditional Chinese medicines clearer.

  12. LEOS 2002: summer electronics and signal processing symposium

    International Nuclear Information System (INIS)

    Karadzhinov, Ljupcho; Ivanovski, Zoran

    2002-01-01

    LEOS 2002 was the first Macedonian symposium on electronics and signal processing. It was organized in recognition to a growing need to exchange the research results as well as to raise competent discussions among different research groups from both academic and industrial environment in Macedonia. The topics covered in this meeting were defined by the IEEE experts as follows: Power Electronics, Industrial Electronics, Signal Processing, Image and Video Processing, Instrumentation and Measurements, Engineering in Medicine and Biology, Electron Devices and Automatic Control. Papers were mainly from Macedonia, but there was one invited lecture

  13. The Tectonics of Love in Leo Tolstoy’s Resurrection

    Directory of Open Access Journals (Sweden)

    Głąb Anna

    2016-09-01

    Full Text Available The text analyzes Leo Tolstoy’s Resurrection focusing on the feelings expressed in the novel. It focuses on: (I the ways in which the content of the novel is expressed through artistic means; (II Tolstoy’s anthropology; (III the notion of love presented by Ronald de Sousa in his last book Love. A Very Short Introduction: the difference between love and mood or emotion; the classification of love (philia, storge, agape, eros; the distinction between love and lust; love as a reason-free desire; and the notion of the historicity of love.

  14. Theory, Practice, and Modernity: Leo Strauss on Rousseau's Epicureanism.

    Science.gov (United States)

    Holley, Jared

    2017-01-01

    This article reconstructs Leo Strauss's reading of Rousseau's Epicureanism to argue that his work is unified by an abiding concern with the problem of theory and practice. Strauss sought to clarify the distinction between theory and practice he considered a fundamental precondition of any properly philosophical reflection on political life, and he explained the pernicious obscuring of that distinction through a narrative tracing the modern modifications of classical Epicureanism. Strauss's critical history of modern political thought is thus part of his attempt to restore the classical distinction between theory and practice to the status of a philosophical problem in modernity.

  15. Los derrames de petróleo : Su impacto ambiental

    OpenAIRE

    Zlatar, Yerko

    1994-01-01

    Los yacimientos de hidrocarburos se localizan, en su mayoría, en lugares alejados de los centros de consumo o de las industrias de procesamiento (destilerías), por tanto el petróleo y sus derivados se transportan mediante embarcaciones de gran tonelaje. Casi el 50% de la flota mundial, que navega a través de las vías marítimas y fluviales, está compuesta por barcos cisternas (tanqueros) que trasladan miles de millones de metros cúbicos de hidrocarburos. Durante las operaciones de carga y desc...

  16. Effects of terrestrial UV radiation on selected outdoor materials: an interdisciplinary approach

    Science.gov (United States)

    Heikkilä, A.; Kazadzis, S.; Tolonen-Kivimäki, O.; Meinander, O.; Lindfors, A.; Lakkala, K.; Koskela, T.; Kaurola, J.; Sormanen, A.; Kärhä, P.; Naula-Iltanen, A.; Syrjälä, S.; Kaunismaa, M.; Juhola, J.; Ture, T.; Feister, U.; Kouremeti, N.; Bais, A.; Vilaplana, J. M.; Rodriguez, J. J.; Guirado, C.; Cuevas, E.; Koskinen, J.

    2009-08-01

    Modern polymeric materials possess an ever increasing potential in a large variety of outdoor objects and structures offering an alternative for many traditional materials. In outdoor applications, however, polymers are subject to a phenomenon called weathering. This is primarily observed as unwanted property changes: yellowing or fading, chalking, blistering, and even severe erosion of the material surface. One of the major weathering factors is UV radiation. In spring 2005, the Finnish Meteorological Institute with its research and industrial partners launched a five-year material research project named UVEMA (UV radiation Effects on MAterials). Within the framework of the project, a weathering network of seven European sites was established. The network extends from the Canary Islands of Spain (latitude 28.5°N) to the Lapland of Finland (latitude 67.4°N), covering a wide range of UV radiation conditions. Since autumn 2005, the sites of the network have been maintaining weathering platforms of specimens of different kinds of polymeric materials. At the same time, the sites have been maintaining their long-term monitoring programmes for spectrally resolved UV radiation. Within UVEMA, these data are used for explaining the differences between the degradation rates of the materials at each site and for correlating the UV conditions in accelerated ageing tests to those under the Sun. We will present the objectives of the UVEMA project aiming at deeper understanding of the ageing of polymers and more reliable assessments for their service life time. Methodologies adopted within the project and the first results of the project will be summarized.

  17. Effect of Selected Alternative Fuels and Raw Materials on the Cement Clinker Quality

    Directory of Open Access Journals (Sweden)

    Strigáč Július

    2015-11-01

    Full Text Available The article deals with the study of the effects of alternative fuels and raw materials on the cement clinker quality. The clinker quality was expressed by the content of two principal minerals alite C3S and belite C2S. The additions of alternative fuels ashes and raw materials, in principle, always increased the belite content and conversely reduced the amount of alite. The alternative fuels with high ash content were used such as the meat-bone meal, sewage sludge from sewage treatment plants and paper sludge and the used alternative raw materials were metallurgical slags - granulated blastfurnace slag, air cooled blastfurnace slag and demetallized steel slag, fluidized bed combustion fly ash and waste glass. Meat-bone meal, sewage sludge from sewage treatment plants and paper sludge were evaluated as moderately suitable alternative fuels which can be added in the amounts of 2.8 wt. % addition of meat-bone meals ash, 3.64 wt. % addition of sewage sludge ash and 3.8 wt. % addition of paper sludge ash to the cement raw mixture. Demetallised steel slag is suitable for production of special sulphate resistant cement clinker for CEM I –SR cement with addition up to 5 wt. %. Granulated blastfurnace slag is a suitable alternative raw material with addition 4 wt. %. Air cooled blastfurnace slag is a suitable alternative raw material with addition 4.2 wt. %. Waste glass is not very appropriate alternative raw material with addition only 1.16 wt. %. Fluidized bed combustion fly ash appears not to be equally appropriate alternative raw material for cement clinker burning with less potential utilization in the cement industry and with addition 3.41 wt. %, which forms undesired anhydrite CaSO4 in the cement clinker.

  18. Radiation tests on selected electrical insulating materials for high-power and high voltage application

    International Nuclear Information System (INIS)

    Liptak, G.; Schuler, R.; Haberthuer, B.; Mueller, H.; Zeier, W.; Maier, P.; Schoenbacher, H.

    1985-01-01

    This report presents a comprehensive set of test results on the irradiation of insulating materials and systems used for the windings of rotating machines, dry-type transformers, and magnet coils. The materials were: Novolac, bisphenol-A, and cycloaliphatic types of epoxy; saturated and unsaturated polyesterimide; silicone, phenolic, and acrylic resins. The reinforcement consisted of glass mat, glass roving, glass cloth, mica paper, polyester mat, polyester roving, polyester cloth, aromatic polyamide paper, or combinations thereof. The materials were irradiated in an 8 MW pool reactor up to integrated doses of 10 8 Gy. On most samples, flexural properties were examined as recommended by IEC Standard 544. For tapes and varnishes, the breakdown voltage was measured. The adhesion of copper bars glued together with an epoxy resin was examined by means of a lap-shear test. A cupping test by means of the Erichsen apparatus was used to measure the flexibility of varnishes. The results are presented in tables and graphs for each of the materials tested. Those from mechanical tests show that the radiation resistance of composite resin-rich insulations depends not only on the base resin combination and the reinforcement material but, to a large degree, also on the adhesion between the two. It appears that better adhesion, and consequently higher radiation resistance, is obtained by special surface treatments of glass fibres. For laminates, higher radiation resistance is obtained with glass mat and resin combinations than with glass cloth as reinforcing materials. The breakdown voltage tests show that the application of mechanical stress to most irradiated samples causes the insulation layer to crack, resulting in lower dielectric strength. For a number of materials, the critical properties of flexural strength and breakdown voltage are above 50% of the initial value at doses between 10 7 and 10 8 Gy, i.e. a radiation index of 7 to 8 at 10 5 Gy/h. (orig.)

  19. Actividad anticaries de una crema dental con propóleos

    Directory of Open Access Journals (Sweden)

    Estela Gispert Abreu

    2000-12-01

    Full Text Available Por muestreo aleatorio simple se seleccionaron 50 escolares con antecedentes de alta infección por Streptococcus mutans, para verificar la actividad anticaries de una crema dental que contiene 0,8 de extracto de propóleo blando. Se perdieron del estudio a 7 escolares por inasistencia y traslados. Se crearon 2 grupos: uno control (n=19 que se cepilló con una crema dental placebo y otro tratamiento (n=24 que se cepilló con la crema dental de propóleo. Entre ambos grupos no había diferencia significativa en el índice de caries COP-D ni en el porcentaje de afectados. Luego de los 10 ciclos de cepillado durante 18 meses, dentro del grupo tratamiento se redujo significativamente en índice de caries y el porcentaje de afectados (Q = p50 students with history of high infection caused by Streptococcus mutans were selected by simple random sampling aimed at verifying the anticaries activity of a tooth paste containing 0.8 of soft propolis extract. 7 students did not conclude the study due to absences and transfers. 2 groups were created: a control group (n = 19 that brushed its teeth with a placebo tooth paste and the other under treatment (n = 24 that used a tooth paste with propolis. There was no significant difference between both groups as regards the COP-D caries index and the percentage of affection. A significant reduction of the caries index and of the percentage of affected individuals (Q = p

  20. Phylogeographic Patterns in Africa and High Resolution Delineation of Genetic Clades in the Lion (Panthera leo)

    NARCIS (Netherlands)

    Bertola, L.D.; Jongbloed, H.; van der Gaag, K.J.; de Knijff, P.; Yamaguchi, N.; Hooghiemstra, H.; Bauer, H.; Henschel, P.; White, P.A.; Driscoll, C.A.; Tende, T.; Ottosson, U.; Saidu, Y.; Vrieling, K.; de Iongh, H.H.

    2016-01-01

    Comparative phylogeography of African savannah mammals shows a congruent pattern in which populations in West/Central Africa are distinct from populations in East/Southern Africa. However, for the lion, all African populations are currently classified as a single subspecies (Panthera leo leo), while

  1. Characterization of Emissions from Building Products: Selection Criteria, Storage and Handling of Indoor Materials for Experiments

    DEFF Research Database (Denmark)

    Kjær, Ulla Dorte; Nielsen, Peter A.; Marcussen, Lis

    1996-01-01

    In research projects it is usually impossible to study more than a very limited aount of different products. Care and consideration must therefore be taken in the selection. The following criteria were used to select five products for chemical and sensory emission testing: The products should...... be indoor climate relevant, meaning that they should be in direct contact with indoor air when used in buildings, and their emission should contribute significantly to the indoor air concentrations for instance due to a large surface area. They should be representative in terms of being widely used, now...... that the emission mechanisms do not change as a consequence of physical processes or chemical reactions. The five products selected were PVC flooring, waterborne varnish on beechwood parquet, carpet, sealant, and waterborne paint on gypsum board. The products were brought to the laboratory immediately after...

  2. Dentist Material Selection for Single-Unit Crowns: Findings from The National Dental Practice-Based Research Network

    Science.gov (United States)

    Makhija, Sonia K.; Lawson, Nathaniel C.; Gilbert, Gregg H.; Litaker, Mark S.; McClelland, Jocelyn A.; Louis, David R.; Gordan, Valeria V.; Pihlstrom, Daniel J.; Meyerowitz, Cyril; Mungia, Rahma; McCracken, Michael S.

    2016-01-01

    Objectives Dentists enrolled in the National Dental Practice-Based Research Network completed a study questionnaire about techniques and materials used for single-unit crowns and an enrollment questionnaire about dentist/practice characteristics. The objectives were to quantify dentists’ material recommendations and test the hypothesis that dentist’s and practice’s characteristics are significantly associated with these recommendations. Methods Surveyed dentists responded to a contextual scenario asking what material they would use for a single-unit crown on an anterior and posterior tooth. Material choices included: full metal, porcelain-fused-to-metal (PFM), all-zirconia, layered zirconia, lithium disilicate, leucite-reinforced ceramic, or other. Results 1,777 of 2,132 eligible dentists responded (83%). The top 3 choices for anterior crowns were lithium disilicate (54%), layered zirconia (17%), and leucite-reinforced glass ceramic (13%). There were significant differences (p<0.05) by dentist’s gender, race, years since graduation, practice type, region, practice busyness, hours worked/week, and location type. The top 3 choices for posterior crowns were all-zirconia (32%), PFM (31%), and lithium disilicate (21%). There were significant differences (p<0.05) by dentist’s gender, practice type, region, practice busyness, insurance coverage, hours worked/week, and location type. Conclusions Network dentists use a broad range of materials for single-unit crowns for anterior and posterior teeth, adopting newer materials into their practices as they become available. Material choices are significantly associated with dentist’s and practice’s characteristics. Clinical Significance Decisions for crown material may be influenced by factors unrelated to tooth and patient variables. Dentists should be cognizant of this when developing an evidence-based approach to selecting crown material. PMID:27693778

  3. Ultrastructural changes of cell walls under intense mechanical treatment of selective plant raw material

    International Nuclear Information System (INIS)

    Bychkov, Aleksey L.; Ryabchikova, E.I.; Korolev, K.G.; Lomovsky, O.I.

    2012-01-01

    Structural changes of cell walls under intense mechanical treatment of corn straw and oil-palm fibers were studied by electron and light microscopy. Differences in the character of destruction of plant biomass were revealed, and the dependence of destruction mechanisms on the structure of cell walls and lignin content was demonstrated. We suggest that the high reactivity of the particles of corn straw (about 18% of lignin) after intense mechanical treatment is related to disordering of cell walls and an increase of the surface area, while in the case of oil palm (10% of lignin) the major contribution into an increase in the reactivity is made by an increase of surface area. -- Highlights: ► Structure of cell walls determines the processes of plant materials' destruction. ► Ultrastructure of highly lignified materials strongly disordering by mechanical action. ► Ultrastructure of low-lignified materials is not disordering by mechanical action.

  4. Mesoporous material grafted with luminescent molecules for the design of selective metal ion chemosensor

    International Nuclear Information System (INIS)

    Zhang Huidong; Zhang Ping; Ye Kaiqi; Sun Yinghui; Jiang Shimei; Wang Yue; Pang Wenqin

    2006-01-01

    Luminescent Schiff-base groups have been successfully grafted on the surface of mesoporous material MCM-48. The grafted Schiff-base groups were employed to prepare luminescent Schiff-base-Zn complex that was covalently bound to the MCM-48 surface. These luminescent mesoporous materials were characterized with X-ray, UV-VIS and emission spectroscopic methods. Experimental results demonstrated that MCM-48 modified with functional groups exhibited novel luminescent property. The chemosensing property of modified MCM-48 sample was investigated. It was demonstrated that the fluorescence of MCM-48 solid with Schiff-base groups could be completely quenched by Cu 2+ cation and this mesoporous material was suitable for sensing Cu 2+ cation in aqueous media

  5. Selection of engineering materials and fabrication of liquid metal fast breeder reactors

    International Nuclear Information System (INIS)

    Patriarca, P.

    1975-01-01

    Information is presented graphically and pictorially concerning the need for nuclear power; basic nuclear concepts including BWR, PWR, HTGR, and LMFBR; the fissioning process; nuclear reactor fuel; fabrication of reactor vessels for LMFBR's; fabrication of intermediate heat exchangers for LMFBR's; piping fabrication for LMFBR's; transition welds; steam generators for LMFBR demonstration plants worldwide; stress corrosion cracking of steam generator materials and weldments; post--test examination of the Alco/BLH sodium-heated steam generator; alternate steam generator designs; and alternate structural materials. (DCC)

  6. Computational Modelling of Materials for Wind Turbine Blades: Selected DTUWind Energy Activities

    DEFF Research Database (Denmark)

    Mikkelsen, Lars Pilgaard; Mishnaevsky, Leon

    2017-01-01

    Computational and analytical studies of degradation of wind turbine blade materials at the macro-, micro-, and nanoscale carried out by the modelling team of the Section Composites and Materials Mechanics, Department of Wind Energy, DTU, are reviewed. Examples of the analysis of the microstructural...... effects on the strength and fatigue life of composites are shown. Computational studies of degradation mechanisms of wind blade composites under tensile and compressive loading are presented. The effect of hybrid and nanoengineered structures on the performance of the composite was studied...

  7. Computational Modelling of Materials for Wind Turbine Blades: Selected DTU Wind Energy Activities.

    Science.gov (United States)

    Mikkelsen, Lars Pilgaard; Mishnaevsky, Leon

    2017-11-08

    Computational and analytical studies of degradation of wind turbine blade materials at the macro-, micro-, and nanoscale carried out by the modelling team of the Section Composites and Materials Mechanics, Department of Wind Energy, DTU, are reviewed. Examples of the analysis of the microstructural effects on the strength and fatigue life of composites are shown. Computational studies of degradation mechanisms of wind blade composites under tensile and compressive loading are presented. The effect of hybrid and nanoengineered structures on the performance of the composite was studied in computational experiments as well.

  8. In situ corrosion studies on selected high level waste packaging materials under simulated disposal conditions in rock salt

    International Nuclear Information System (INIS)

    Smailos, E.; Schwarzkopf, W.; Koester, R.

    1988-01-01

    In order to qualify corrosion resistant materials for high level waste (HLW) packagings acting as a long-term barrier in a rock salt repository, the corrosion behavior of preselected materials is being investigated in laboratory-scale and in-situ experiments. This work reports about in-situ corrosion experiments on unalloyed steels, Ti 99.8-Pd, Hastelloy C4, and iron-base alloys, as nodular cast iron, Ni-Resist D4 and Si-cast iron, under simulated disposal conditions. The results of the investigations can be summarized as follows: (1) all materials investigated exhibited high resistance to corrosion under the conditions prevailing in the Brine Migration Test; (2) all materials and above all the materials with passivating oxide layers such as Ti 99.8-Pd and Hastelloy C4 which may corrode selectively already in the presence of minor amounts of brine had been resistant with respect to any type of local corrosion attack; the gamma-radiation of 3 · 10 2 Gy/h did not exert an influence on the corrosion behavior of the materials

  9. Growth and characterization of AlxGa1-xN LEO substrates

    International Nuclear Information System (INIS)

    Paek, H.S.; Sakong, T.; Lee, S.N.; Son, J.K.; Ryu, H.Y.; Nam, O.H.; Park, Y.

    2006-01-01

    We have studied the effect of Al composition on the properties of Al x Ga 1-x N LEO substrates. Al x Ga 1-x N LEO substrates were prepared on stripe-patterned 2μm-thick undoped GaN/sapphire substrates by metalorganic chemical vapor deposition. To investigate the dislocation and crack density, and the surface morphology of Al x Ga 1-x N LEO substrates with different Al compositions, photoluminescence and optical microscope were used. At a 1% of Al composition, we obtained crack-free and mirror-like substrates having a low dislocation density of ∼1E6cm -2 . We expect considerable reduction in threshold current density to be achieved from blue-violet laser diodes grown on Al x Ga 1-x N LEO substrates because of the increased optical gain, as compared to the laser diodes grown on Al-free LEO substrates

  10. Selected Bibliography of Egyptian Educational Materials, Vol. 2, No. 3, 1976.

    Science.gov (United States)

    Al-Ahram Center for Scientific Translations, Cairo (Egypt).

    The selective annotated bibliography of Egyptian educational publications contains 109 entries on 42 topics. Included are journal articles, books, and government documents published during 1976. Content includes the following topics: adult education, art education, audiovisual aids, care for distinguished students, educational planning,…

  11. Selected Bibliography of Egyptian Educational Materials, Vol. 2, No. 2, 1976.

    Science.gov (United States)

    Al-Ahram Center for Scientific Translations, Cairo (Egypt).

    One hundred fourteen entries on 58 topics are contained in the selective annotated bibliography of Egyptian publications on education. Included are journal articles, books, and government documents published during 1976. Content includes the following topics: adult education, Arabic language, audiovisual aids, child upbringing, civics, economics…

  12. Selected Bibliography of Egyptian Educational Materials, Vol. 2, No. 1, 1976.

    Science.gov (United States)

    Al-Ahram Center for Scientific Translations, Cairo (Egypt).

    This selective annotated bibliography of Egyptian publications on education contains 126 entries on 55 topics. Publications include journal articles, books, and government documents published during 1976 or late 1975. Among the 55 topics are the following: adult education, agricultural schools, art education, child upbringing, compulsory…

  13. Selected Bibliography of Egyptian Educational Materials, Vol. 2, No. 4, 1976.

    Science.gov (United States)

    Al-Ahram Center for Scientific Translations, Cairo (Egypt).

    One hundred seventy entries on 69 topics are contained in the selective annotated bibliography of Egyptian publications on education. Included are journal articles, books, and government documents published during 1976. Content includes the following topics: Arabic language, art education, civics, commercial schools, comparative education,…

  14. Avaliação da qualidade do óleo de palma e frações (Elaeis guineenses) armazenados em diferentes condições de estocagem

    OpenAIRE

    Matos, Vanessa de Souza

    2015-01-01

    O óleo de palma bruto (OPB) ou azeite de dendê (Elaeis guineenses) apresenta composição equilibrada em ácidos graxos saturados e insaturados, o que permite fracionar o óleo em dois principais componentes: fração líquida, a oleína de palma e fração sólida, a estearina. A degradação do óleo de palma durante armazenamento pode ser provocada pela ação da luz natural ou artificial, hidrólise autocatalítica, umidade, temperatura, material utilizado nas embalagens, ar e por micro-orga...

  15. Gengibre (zingiber officinale roscoe brasileiro: aspectos gerais, óleo essencial e oleoresina. parte 2 - secagem, óleo essencial e oleoresina

    Directory of Open Access Journals (Sweden)

    Mauro Taveira Magalhães

    1997-08-01

    Full Text Available A partir de amostras de gengibre (Zingiber officinale Roscoe do tipo "Gigante", oriundas das diversas localidades produtoras do Brasil, procurou-se estabelecer as melhores condições de processamento e verificar a qualidade do óleo essencial e da oleoresina obtidos. A composição do óleo essencial de gengibre gigante varia de acordo com a técnica de extração e o estado do rizoma. Os óleos essenciais de rizomas frescos e secos foram comparados através de seus índices físico-químicos e composição por CG. São apresentadas as características do óleo essencial do rizoma seco obtido por arraste direto a vapor. Nas oleoresinas obtidas com diferentes solventes determinou-se o teor de óleo essencial. O gengibre comercial brasileiro fornece óleo essencial num rendimento de 2,2% e oleoresina em rendimentos que variam de 6,91-10,90% (etanol, 2,53-5,62% (acetona e 3,35-3,91% (dicloroetano, sendo alternativas interessantes de utilização.

  16. Guidelines for Selecting Control and Treatment Options for Contaminated Dredged Material.

    Science.gov (United States)

    1986-09-01

    is being used to predict surface runoff water quality from dredged material as part of the CE/EPA FVP ( Westerdahl and Skogerboe 1981, Lee and...April 20, 1984. Water Pollution Control Federation. 1976. "Chlorination of Wastewater," Manual of Practice No. 4, Washington, D.C. Westerdahl , H. E

  17. Assessing the Impact of Removing Select Materials from Coal Mine Overburden, Central Appalachia Region, USA

    Science.gov (United States)

    The exposure of readily soluble components of overburden materials from surface coal mining to air and water results in mineral oxidation and carbonate mineral dissolution, thus increasing coal mine water conductivity. A conductivity benchmark of 300 µS/cm for mine water dischar...

  18. Challenges of selecting materials for the process of biomass gasification in supercritical water

    Energy Technology Data Exchange (ETDEWEB)

    Boukis, N.; Habicht, W.; Hauer, E.; Dinjus, E. [Karlsruher Institut fuer Technologie (KIT), Karlsruhe (Germany). Inst. fuer Technische Chemie

    2010-07-01

    A new process for the gasification of wet biomass is the reaction in supercritical water. The product is a combustible gas, rich in hydrogen with a high calorific value. The reaction is performed under high temperatures - up to 700 C - and pressures up to 30 MPa. The combination of these physical conditions and the corrosive environment is very demanding for the construction materials of the reactor. Only few alloys exhibit the required mechanical properties, especially the mechanical strength at temperatures higher than 600 C. Ni-Base alloys like alloy 625 can be applied up to a temperature of 700 C and are common materials for application under supercritical water conditions. During gasification experiments with corn silage and other biomasses, corrosion of the reactor material alloy 625 appears. The gasification of an aqueous methanol solution in supercritical water at temperatures up to 600 C and 25 - 30 MPa pressure results in an product gas rich in hydrogen, carbon dioxide and some methane. Alloy 625 shows very low corrosion rates in this environment. It is obvious that the heteroatoms and salts present in biomass cause corrosion of the reactor material. (orig.)

  19. Instrumental neutron and photon activation analyses of selected geochemical reference materials

    Czech Academy of Sciences Publication Activity Database

    Mizera, Jiří; Řanda, Zdeněk

    2010-01-01

    Roč. 284, č. 1 (2010), s. 157-163 ISSN 0236-5731 R&D Projects: GA AV ČR IAA300130706 Institutional research plan: CEZ:AV0Z10480505 Keywords : neutron activation analysis * photon activation analysis * geochemical reference materials Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 0.777, year: 2010

  20. Instrumental neutron and photon activation analyses of selected geochemical reference materials

    Czech Academy of Sciences Publication Activity Database

    Mizera, Jiří; Řanda, Z.

    2010-01-01

    Roč. 284, č. 1 (2010), s. 157-163 ISSN 0236-5731 Institutional research plan: CEZ:AV0Z30460519 Keywords : neutron activation analysis * photon activation analysis * geochemical reference materials Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders OBOR OECD: Analytical chemistry Impact factor: 0.777, year: 2010

  1. Selected Bibliography of Egyptian Educational Materials. Vol. 5, No. 2, 1979.

    Science.gov (United States)

    Al-Ahram Center for Scientific Translations, Cairo (Egypt).

    One hundred and forty two books, articles, and government publications dealing with education in Egypt are cited in this annotated bibliography. Items cited were published in 1979 and examine education for all age groups and ability levels. The material is presented under 84 headings including adult education, art education, children's books,…

  2. Selected Bibliography of Egyptian Educational Materials. Vol. 3, No. 4, 1977.

    Science.gov (United States)

    Al-Ahram Center for Scientific Translations, Cairo (Egypt).

    Over 130 citations of books, journals, government publications, and newspapers dealing with education in Egypt are included in this annotated bibliography. Materials cited were published in 1977. Sixty-two alphabetically arranged categories cover such topics as agricultural schools, Arabic language, basic education, child care, curricula,…

  3. Stress corrosion cracking susceptibility of selected materials for steam plant bolting applications

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, P.; Noga, J.O.; Ogundele, G.

    1996-12-01

    The incidence of alloy steel bolting failure in nuclear and fossil fired generating plants was discussed. The problem manifests itself in the form of intergranular stress corrosion cracking. A study was conducted to rank the susceptibility of three materials (Alloy AISI, type 4140, Alloy ASTM A564-92AXM 13 and Inconel 718) to stress corrosion cracking and to determine threshold stress intensity factors of currently used and alternate alloys in service environments typically encountered in steam generating utility plants. Although most alloy steel bolting failures have involved Cr-Mo, failures have also been reported for all the above mentioned materials. Attempts to minimize the occurrence of stress corrosion cracking have involved a ban on molybdenum disulphide, limiting bolt tightening torque and placing an upper limit on bolt hardness, and by correlation on tensile strength. Slow strain rate and wedge opening-loading specimen tests were used to evaluate commonly used and superior alternative bolting materials. Electrochemical polarization tests were also conducted. Threshold stresses in a H{sub 2}S environment were determined according to NACE standard TM-01-77. Results showed that, to a certain degree, all tested materials were susceptible to stress corrosion cracking. They ranked as follows from best to worst performance: (1) the Inconel 718, (2) alloy SM 13, and (3) alloy 4140. 9 refs., 20 tabs., 34 figs.

  4. Analytical review of minimum critical mass values for selected uranium and plutonium materials

    International Nuclear Information System (INIS)

    Morman, J.A.; Henrikson, D.J.; Garcia, A.S.

    1997-01-01

    Current subcritical limits for a number of uranium and plutonium materials (metals and compounds) as given in the ANSI/ANS standards for criticality safety are based on evaluations performed in the late 1970s and early 1980s. This paper presents the results of an analytical study of the minimum critical mass values for a set of materials using current codes and standard cross section sets. This work is meant to produce a consistent set of minimum critical mass values that can form the basis for adding new materials to the single-parameter tables in ANSI/ANS-8.1. Minimum critical mass results are presented for bare and water reflected full-density spheres and for full density moist (1.5 wt-% water) as calculated with KENO-Va, MCNP4A and ONEDANT. Calculations were also performed for both dry and moist materials at one-half density. Some KENO calculations were repeated using several cross section sets to examine potential bias differences. The results of the calculations were compared to the currently accepted subcritical limits. The calculated minimum critical mass values are reasonably consistent for the three codes, and differences most likely reflect differences in the cross section sets. The results are also consistent with values given in ANSI/ANS-8.1. 3 refs., 2 tabs

  5. Selection of environmental sustainable fiber materials for wind turbine blades - a contra intuitive process?

    Energy Technology Data Exchange (ETDEWEB)

    Birkved, M.; Corona, A. [Technical Univ. of Denmark. DTU Management Engineering, Kgs. Lyngby (Denmark); Markussen, C.M.; Madsen, Bo [Technical Univ. of Denmark. DTU Wind Energy, Risoe Campus, Roskilde (Denmark)

    2013-09-01

    Over the recent decades biomaterials have been marketed successfully supported by the common perception that biomaterials and environmental sustainability de facto represents two sides of the same coin. The development of sustainable composite materials such as blades for small-scale wind turbines have thus partially been focused on the substitution of conventional fiber materials with bio-fibers. The major question is if this material substitution actually, is environmental sustainable. In order to assess a wide pallet of environmental impacts and taking into account positive and negative environmental trade-offs over the entire life-span of composite materials, life cycle assessment (LCA) can be applied. In the present case study, four different types of fibers (carbon, glass, flax and carbon/flax mixture) are compared in terms of environmental sustainability and cost. Applying one of the most recent life cycle impact assessment methods, it is demonstrated that the environmental sustainability of the mixed carbon/flax fiber based composite material is better than that of the flax fibers alone. This observation may be contra-intuitive, but is mainly caused by the fact that the bio-material resin demand is by far exceeding the resin demand of the conventional fibers, and since the environmental burden of the resin is comparable to that of the fibers, resin demand is in terms of environmental sustainability important. On the other hand is the energy demand and associated environmental impacts in relation to the production of the carbon and glass fibers considerable compared to the impacts resulting from resin production. The ideal fiber solution, in terms of environmental sustainability, is hence the fiber composition having the lowest resin demand and lowest overall energy demand. The optimum environmental solution hence turns out to be a 70:30 flax:carbon mix, thereby minimizing the use of carbon fibers and resin. On top of the environmental sustainability

  6. Materialism.

    Science.gov (United States)

    Melnyk, Andrew

    2012-05-01

    Materialism is nearly universally assumed by cognitive scientists. Intuitively, materialism says that a person's mental states are nothing over and above his or her material states, while dualism denies this. Philosophers have introduced concepts (e.g., realization and supervenience) to assist in formulating the theses of materialism and dualism with more precision, and distinguished among importantly different versions of each view (e.g., eliminative materialism, substance dualism, and emergentism). They have also clarified the logic of arguments that use empirical findings to support materialism. Finally, they have devised various objections to materialism, objections that therefore serve also as arguments for dualism. These objections typically center around two features of mental states that materialism has had trouble in accommodating. The first feature is intentionality, the property of representing, or being about, objects, properties, and states of affairs external to the mental states. The second feature is phenomenal consciousness, the property possessed by many mental states of there being something it is like for the subject of the mental state to be in that mental state. WIREs Cogn Sci 2012, 3:281-292. doi: 10.1002/wcs.1174 For further resources related to this article, please visit the WIREs website. Copyright © 2012 John Wiley & Sons, Ltd.

  7. Selective propensity of bovine jugular vein material to bacterial adhesions: An in-vitro study.

    Science.gov (United States)

    Jalal, Zakaria; Galmiche, Louise; Lebeaux, David; Villemain, Olivier; Brugada, Georgia; Patel, Mehul; Ghigo, Jean-Marc; Beloin, Christophe; Boudjemline, Younes

    2015-11-01

    Percutaneous pulmonary valve implantation (PPVI) using Melody valve made of bovine jugular vein is safe and effective. However, infective endocarditis has been reported for unclear reasons. We sought to assess the impact of valvular substrates on selective bacterial adhesion. Three valved stents (Melody valve, homemade stents with bovine and porcine pericardium) were tested in-vitro for bacterial adhesion using Staphylococcus aureus and Streptococcus sanguinis strains. Bacterial adhesion was higher on bovine jugular venous wall for S. aureus and on Melody valvular leaflets for S. sanguinis in control groups and significantly increased in traumatized Melody valvular leaflets with both bacteria (traumatized vs non traumatized: p=0.05). Bacterial adhesion was lower on bovine pericardial leaflets. Selective adhesion of S. aureus and S. sanguinis pathogenic strains to Melody valve tissue was noted on healthy tissue and increased after implantation procedural steps. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  8. Chemical-technological approach to the selection of ceramic materials with predetermined thermistor properties

    Energy Technology Data Exchange (ETDEWEB)

    Plewa, J.; Altenburg, H. [Fachhochschule Muenster, Steinfurt (Germany). SIMa and Supraleiter-Keramik-Kristalle; Brunner, M. [Fachhochschule Koeln (Germany). Elektronische Bauelemente; Shpotyuk, O.; Vakiv, M. [Scientific Research Co. ' ' Carat' ' , Lviv Scientific Research Inst. of Materials, Lviv (Ukraine)

    2002-07-01

    The selection possibilities of quaternary Cu-Ni-Co-Mn oxide system restricted by cubic spinels (CuMn{sub 2}O{sub 4}, MnCo{sub 2}O{sub 4} and NiMn{sub 2}O{sub 4}) for NTC thermistors application were discussed. Phase compositions, microstructural features and electrical properties of the investigated spinel-structured ceramics were studied in tight connection with technological regimes of their sintering. (orig.)

  9. Angular selectivity asymmetry of holograms recorded in near infrared sensitive liquid crystal photopolymerizable materials

    Science.gov (United States)

    Harbour, Steven; Galstian, Tigran; Akopyan, Rafik; Galstyan, Artur

    2004-08-01

    We have experimentally observed and theoretically explained the angular selectivity asymmetry in polymer dispersed liquid crystal holograms. Experiments are conducted in compounds with near infrared sensitivity. The coupled-wave theory is used to describe the diffraction properties of obtained anisotropic holographic gratings. Furthermore, the comparison of theory and experiments provides information about the optical axis direction that is defined by the average molecular orientation of the liquid crystal in the polymer matrix.

  10. Selection of environmental sustainable fiber materials for wind turbine blades - a contra intuitive process?

    DEFF Research Database (Denmark)

    Birkved, Morten; Corona, Andrea; Markussen, Christen Malte

    2013-01-01

    environmental trade-offs over the entire life-span of composite materials, life cycle assessment (LCA) can be applied. In the present case study, four different types of fibers (carbon, glass, flax and carbon/flax mixture) are compared in terms of environmental sustainability and cost. Applying one of the most...... recent life cycle impact assessment methods, it is demonstrated that the environmental sustainability of the mixed carbon/flax fiber based composite material is better than that of the flax fibers alone. This observation may be contra-intuitive, but is mainly caused by the fact that the bio...... impacts in relation to the production of the carbon and glass fibers considerable compared to the impacts resulting from resin production. The ideal fiber solution, in terms of environmental sustainability, is hence the fiber composition having the lowest resin demand and lowest overall energy demand...

  11. Selected scientific articles. (Investigations in the field of hydrides chemistry and mineral raw materials processing)

    International Nuclear Information System (INIS)

    Mirsaidov, U.M.

    2013-01-01

    Articles, included in the present book are covering period 1977-2013 y. The main scientific articles in the field of power-consuming substances, mineral raw-materials and wastes reprocessing, including uranium industry wastes are collected. Scientific works on hydrogen chemistry which carried out basically bu U.M. Mirsaidov without co-authors are considered. These works are on aluminium hydrides and borohydrides lanthanides. Besides, author's popular-science articles on research carried out by Academy of Sciences during the period when he was the President of Academy of Sciences of the Republic of Tajikistan (1995-2005) are included. Mineral raw materials and wastes reprocessing results are given as well. The book is intended for engineer and technical staff, those working in the field of hydrogen chemistry, hydrometallurgy workers, engineering chemists as well as for PhD, post graduate students and students of appropriate profiles.

  12. A Materials and Equipment Review of Selected U.S. Geothermal District Heating Systems

    Energy Technology Data Exchange (ETDEWEB)

    Rafferty, K D [P.E.

    0000-12-30

    Geothermal district heating systems are now quite common in the western U.S. A recent survey identified a total of 17 such systems. The performance of materials and equipment in 13 of these systems is reviewed in this paper. Specific areas covered include: production facilities, central plants, distribution, customer connection, metering and disposal. Those areas: characterized by the highest incidence of problems include: production well pumps, customer branch piping and energy metering.

  13. Choice Experiment Analysis of Outdoor Decking Material Selection in E-Commerce Market in Finland

    OpenAIRE

    Holopainen, Jani Markus; Toppinen, Anne Maarit Kristiina; Lähtinen, Katja Päivikki; Rekola, Mika Olavi

    2017-01-01

    Since the early 1990s, there has been hope that the uptake of certified forest products would ensure more sustainable forest management and also deliver business benefits along the value chain. Our study applies a Discrete Choice Experiment (DCE) to model an e-commerce purchase in the case of multiple products with various attribute and certification combinations in the Finnish retail outdoor decking material market. We received 2772 responses from 231 participants in an online survey. Applyi...

  14. Materialism, empathy and willingness to help as correlates of university and faculty selection

    Directory of Open Access Journals (Sweden)

    Sabina Kołodziej

    2016-09-01

    Full Text Available The article presents results of two studies on the issue of individual characteristics as factors related to the choice of the type of university or faculty. The study 1 is focused on the level of materialism as well as the definition of a life success formulated by private and state university students. The study 2 analyses the propensity to help other people and the level of empathy among pedagogics and business students. Studies were conducted with DSM (Górnik-Durose, 2002 scale measuring materialism and designed life- success questionnaire (study 1 or IRI scale developed by Davis (1980 measuring the level of empathy (study 2. The sample amounted to 92 respondents in both studies. Results show that private university students are characterized by a higher level of materialism than public university students. Students from private university, in comparison with state university students, also score higher success in life of a person with higher income. According to the results of study 2, students of pedagogics declare higher willingness to help than business students and are characterized as experiencing more positive feelings for other people who are in a difficult situation

  15. Selectively Modulating Triplet Exciton Formation in Host Materials for Highly Efficient Blue Electrophosphorescence.

    Science.gov (United States)

    Li, Huanhuan; Bi, Ran; Chen, Ting; Yuan, Kai; Chen, Runfeng; Tao, Ye; Zhang, Hongmei; Zheng, Chao; Huang, Wei

    2016-03-23

    The concept of limiting the triplet exciton formation to fundamentally alleviate triplet-involved quenching effects is introduced to construct host materials for highly efficient and stable blue phosphorescent organic light-emitting diodes (PhOLEDs). The low triplet exciton formation is realized by small triplet exciton formation fraction and rate with high binding energy and high reorganization energy of triplet exciton. Demonstrated in two analogue molecules in conventional donor-acceptor molecule structure for bipolar charge injection and transport with nearly the same frontier orbital energy levels and triplet excited energies, the new concept host material shows significantly suppressed triplet exciton formation in the host to avoid quenching effects, leading to much improved device efficiencies and stabilities. The low-voltage-driving blue PhOLED devices exhibit maximum efficiencies of 43.7 cd A(-1) for current efficiency, 32.7 lm W(-1) for power efficiency, and 20.7% for external quantum efficiency with low roll-off and remarkable relative quenching effect reduction ratio up to 41%. Our fundamental solution for preventing quenching effects of long-lived triplet excitons provides exciting opportunities for fabricating high-performance devices using the advanced host materials with intrinsically small triplet exciton formation cross section.

  16. First-Principles Integrated Adsorption Modeling for Selective Capture of Uranium from Seawater by Polyamidoxime Sorbent Materials.

    Science.gov (United States)

    Ladshaw, Austin P; Ivanov, Alexander S; Das, Sadananda; Bryantsev, Vyacheslav S; Tsouris, Costas; Yiacoumi, Sotira

    2018-04-18

    Nuclear power is a relatively carbon-free energy source that has the capacity to be utilized today in an effort to stem the tides of global warming. The growing demand for nuclear energy, however, could put significant strain on our uranium ore resources, and the mining activities utilized to extract that ore can leave behind long-term environmental damage. A potential solution to enhance the supply of uranium fuel is to recover uranium from seawater using amidoximated adsorbent fibers. This technology has been studied for decades but is currently plagued by the material's relatively poor selectivity of uranium over its main competitor vanadium. In this work, we investigate the binding schemes between uranium, vanadium, and the amidoxime functional groups on the adsorbent surface. Using quantum chemical methods, binding strengths are approximated for a set of complexation reactions between uranium and vanadium with amidoxime functionalities. Those approximations are then coupled with a comprehensive aqueous adsorption model developed in this work to simulate the adsorption of uranium and vanadium under laboratory conditions. Experimental adsorption studies with uranium and vanadium over a wide pH range are performed, and the data collected are compared against simulation results to validate the model. It was found that coupling ab initio calculations with process level adsorption modeling provides accurate predictions of the adsorption capacity and selectivity of the sorbent materials. Furthermore, this work demonstrates that this multiscale modeling paradigm could be utilized to aid in the selection of superior ligands or ligand compositions for the selective capture of metal ions. Therefore, this first-principles integrated modeling approach opens the door to the in silico design of next-generation adsorbents with potentially superior efficiency and selectivity for uranium over vanadium in seawater.

  17. Selective Adsorption of Nano-bio materials and nanostructure fabrication on Molecular Resists Modified by proton beam irradiation

    International Nuclear Information System (INIS)

    Lee, H. W.; Kim, H. S.; Kim, S. M.

    2008-04-01

    The purpose of this research is the fabrication of nanostructures on silicon substrate using proton beam and selectively adsorption of bio-nano materials on the patterned substrate. Recently, the miniaturization of the integrated devices with fine functional structures was intensively investigated, based on combination of nanotechnology (NT), biotechnology (BT) and information technology (IT). Because of the inherent limitation in optical lithography, large variety of novel patterning technologies were evolved to construct nano-structures onto a substrate. Atomic force microscope-based nanolithography has readily formed sub-50 nm patterns by the local modification of a substrate using a probe with a curvature of 10 nm. The surface property was regarded as one of the most important factors for AFM-based nanolithography as well as for other novel nanolithographies. The molecular thin films such as a self-assembled monolayer or a polymer resist layer have been used as an alternative to modifying the surface property. Although proton or ion beam irradiation has been used as an efficient tool to modify the physical, chemical and electrical properties of a surface, the nano-patterning on the substrate or the molecular film modified with the beam irradiation has hardly been studied at both home and abroad. The selective adsorption of nano-bio materials such as carbon nanotubes and proteins on the patterns would contribute to developing the integrated devices. The polystyrene nanoparticles (400 nm) were arrayed on al silicon surface using nanosphere lithography and the various nanopatterns were fabricated by proton beam irradiation on the polystyrene nanoparticles arrayed silicon surface. We obtained the two different nanopatterns such as polymer nanoring patterns and silicon oxide patterns on the same silicon substrate. The polymer nanoring patterns formed by the crosslinkage of polystyrene when proton beam was irradiated at the triangular void spaces that are enclosed by

  18. Synthesis of Homoveratric Acid-Imprinted Polymers and Their Evaluation as Selective Separation Materials

    Directory of Open Access Journals (Sweden)

    Mariusz Dana

    2011-05-01

    Full Text Available A bulk polymerization method was used to easily and efficiently prepare homo-veratric acid (3,4-dimethoxyphenylacetic acid-imprinted polymers from eight basic monomers: 2-vinylpyridine, 4-vinylpyridine, 1-vinylimidazole, N-allylaniline, N-allylpiperazine, allylurea, allylthiourea, and allylamine, in the presence of homoveratric acid as a template in N,N-dimethylformamide as a porogen. The imprinted polymer prepared from allylamine had the highest affinity to the template, showing an imprinting factor of 3.43, and allylamine polymers MIP8/NIP8 were selected for further studies. Their binding properties were analyzed using the Scatchard method. The results showed that the imprinted polymers have two classes of heterogeneous binding sites characterized by two pairs of Kd, Bmax values: Kd(1 = 0.060 μmol/mL, Bmax(1 = 0.093 μmol/mg for the higher affinity binding sites, and Kd(2 = 0.455 μmol/mL, Bmax(2 = 0.248 μmol/mg for the lower affinity binding sites. Non-imprinted polymer has only one class of binding site, with Kd = 0.417 μmol/mL and Bmax = 0.184 μmol/mg. A computational analysis of the energies of the prepolymerization complexes was in agreement with the experimental results. It showed that the selective binding interactions arose from cooperative three point interactions between the carboxylic acid and the two methoxy groups in the template and amino groups in the polymer cavities. Those results were confirmed by the recognition studies performed with the set of structurally related compounds. Allylamine polymer MIP8 had no affinity towards biogenic amines. The obtained imprinted polymer could be used for selective separation of homoveratric acid.

  19. Molecularly Imprinted Porous Monolithic Materials from Melamine-Formaldehyde for Selective Trapping of Phosphopeptides

    DEFF Research Database (Denmark)

    Liu, Mingquan; Tran, Tri Minh; Abbas Elhaj, Ahmed Awad

    2017-01-01

    monoliths, chosen based on the combination of meso- and macropores providing optimal percolative flow and accessible surface area, was synthesized in the presence of N-Fmoc and O-Et protected phosphoserine and phosphotyrosine to prepare molecularly imprinted monoliths with surface layers selective...... for phosphopeptides. These imprinted monoliths were characterized alongside nonimprinted monoliths by a variety of techniques and finally evaluated by liquid chromatography-mass spectrometry in the capillary format to assess their abilities to trap and release phosphorylated amino acids and peptides from partly...

  20. Fatigue Life Assessment of Selected Engineering Materials Based on Modified Low-Cycle Fatigue Test

    Directory of Open Access Journals (Sweden)

    M. Maj

    2013-01-01

    Full Text Available In this study, the mechanical tests were carried out on ductile iron of EN-GJS-600-3 grade and on grey cast iron of EN-GJL-250 grade.The fatigue life was evaluated in a modified low-cycle fatigue test (MLCF, which enables the determination of parameters resulting fromthe Manson-Coffin-Morrow relationship.The qualitative and quantitative metallographic studies conducted by light microscopy on selected samples of ductile iron with spheroidalgraphite and grey cast iron with lamellar graphite (showing only small variations in mechanical properties, confirmed also smallvariations in the geometrical parameters of graphite related with its content and morphological features.

  1. Fatigue Life Assessment of Selected Engineering Materials Based on Modified Low-Cycle Fatigue Test

    Directory of Open Access Journals (Sweden)

    Maj M.

    2013-03-01

    Full Text Available In this study, the mechanical tests were carried out on ductile iron of EN-GJS-600-3 grade and on grey cast iron of EN-GJL-250 grade. The fatigue life was evaluated in a modified low-cycle fatigue test (MLCF, which enables the determination of parameters resulting from the Manson-Coffin-Morrow relationship. The qualitative and quantitative metallographic studies conducted by light microscopy on selected samples of ductile iron with spheroidal graphite and grey cast iron with lamellar graphite (showing only small variations in mechanical properties, confirmed also small variations in the geometrical parameters of graphite related with its content and morphological features.

  2. Using the Analytic Hierarchy Process to Prioritize and Select Phase Change Materials for Comfort Application in Buildings

    Directory of Open Access Journals (Sweden)

    Socaciu Lavinia Gabriela

    2014-03-01

    Full Text Available Phase change materials (PCMs selection and prioritization for comfort application in buildings have a significant contribution to the improvement of latent heat storage systems. PCMs have a relatively large thermal energy storage capacity in a temperature range close to their switch point. PCMs absorb energy during the heating process as phase change takes place and release energy to the environment in the phase change range during a reverse cooling process. Thermal energy storage systems using PCMs as storage medium offer advantages such as: high heat storage capacity and store/release thermal energy at a nearly constant temperature, relative low weight, small unit size and isothermal behaviour during charging and discharging when compared to the sensible thermal energy storage. PCMs are valuable only in the range of temperature close to their phase change point, since their main thermal energy storage capacity depend on their mass and on their latent heat of fusion. Selection of the proper PCMs is a challenging task because there are lots of different materials with different characteristics. In this research paper the principles and techniques of the Analytic Hierarchy Process (AHP are presented, discussed and applied in order to prioritize and select the proper PCMs for comfort application in buildings. The AHP method is used for solving complex decisional problems and allows the decision maker to take the most suitable decisions for the problem studied. The results obtained reveal that the AHP method can be successfully applied when we want to choose a PCM for comfort application in buildings.

  3. Selective ablation of photovoltaic materials with UV laser sources for monolithic interconnection of devices based on a-Si:H

    Energy Technology Data Exchange (ETDEWEB)

    Molpeceres, C. [Centro Laser UPM, Univ. Politecnica de Madrid, Crta. de Valencia Km 7.3, 28031 Madrid (Spain)], E-mail: carlos.molpeceres@upm.es; Lauzurica, S.; Garcia-Ballesteros, J.J.; Morales, M.; Guadano, G.; Ocana, J.L. [Centro Laser UPM, Univ. Politecnica de Madrid, Crta. de Valencia Km 7.3, 28031 Madrid (Spain); Fernandez, S.; Gandia, J.J. [Dept. de Energias Renovables, Energia Solar Fotovoltaica, CIEMAT, Avda, Complutense 22, 28040 Madrid (Spain); Villar, F.; Nos, O.; Bertomeu, J. [CeRMAE Dept. Fisica Aplicada i Optica, Universitat de Barcelona, Av. Diagonal 647, 08028 Barcelona (Spain)

    2009-03-15

    Lasers are essential tools for cell isolation and monolithic interconnection in thin-film-silicon photovoltaic technologies. Laser ablation of transparent conductive oxides (TCOs), amorphous silicon structures and back contact removal are standard processes in industry for monolithic device interconnection. However, material ablation with minimum debris and small heat affected zone is one of the main difficulty is to achieve, to reduce costs and to improve device efficiency. In this paper we present recent results in laser ablation of photovoltaic materials using excimer and UV wavelengths of diode-pumped solid-state (DPSS) laser sources. We discuss results concerning UV ablation of different TCO and thin-film silicon (a-Si:H and nc-Si:H), focussing our study on ablation threshold measurements and process-quality assessment using advanced optical microscopy techniques. In that way we show the advantages of using UV wavelengths for minimizing the characteristic material thermal affection of laser irradiation in the ns regime at higher wavelengths. Additionally we include preliminary results of selective ablation of film on film structures irradiating from the film side (direct writing configuration) including the problem of selective ablation of ZnO films on a-Si:H layers. In that way we demonstrate the potential use of UV wavelengths of fully commercial laser sources as an alternative to standard backscribing process in device fabrication.

  4. Selective ablation of photovoltaic materials with UV laser sources for monolithic interconnection of devices based on a-Si:H

    International Nuclear Information System (INIS)

    Molpeceres, C.; Lauzurica, S.; Garcia-Ballesteros, J.J.; Morales, M.; Guadano, G.; Ocana, J.L.; Fernandez, S.; Gandia, J.J.; Villar, F.; Nos, O.; Bertomeu, J.

    2009-01-01

    Lasers are essential tools for cell isolation and monolithic interconnection in thin-film-silicon photovoltaic technologies. Laser ablation of transparent conductive oxides (TCOs), amorphous silicon structures and back contact removal are standard processes in industry for monolithic device interconnection. However, material ablation with minimum debris and small heat affected zone is one of the main difficulty is to achieve, to reduce costs and to improve device efficiency. In this paper we present recent results in laser ablation of photovoltaic materials using excimer and UV wavelengths of diode-pumped solid-state (DPSS) laser sources. We discuss results concerning UV ablation of different TCO and thin-film silicon (a-Si:H and nc-Si:H), focussing our study on ablation threshold measurements and process-quality assessment using advanced optical microscopy techniques. In that way we show the advantages of using UV wavelengths for minimizing the characteristic material thermal affection of laser irradiation in the ns regime at higher wavelengths. Additionally we include preliminary results of selective ablation of film on film structures irradiating from the film side (direct writing configuration) including the problem of selective ablation of ZnO films on a-Si:H layers. In that way we demonstrate the potential use of UV wavelengths of fully commercial laser sources as an alternative to standard backscribing process in device fabrication.

  5. Detection of heat abduction on the walls by artificial neural network and selection of materials with decision support system

    Directory of Open Access Journals (Sweden)

    Egemen Tekkanat

    2017-08-01

    Full Text Available Today energy conservation is a very important issue in the world and Turkey. The aim of this study is to minimize the heat abduction, thus to save energy by utilizing the factors to prevent the heat abduction on the walls of buildings. First of all, a back-propagation network model with artificial neural network model was used for the factors that can cause heat loss on the walls. Whether the walls have insulation were considered. After that, Decision Support Systems were used for heat insulation to select the appropriate materials. A Decision Support Model with Analytic Hierarchy Process (AHP was recommended to meet the needs of a customer best and to make better decisions for the selection of the materials. The method was used by construction firms for their decision processes for the best materials and the results were evaluated. After the evaluations were done, the factors that cause heat loss were considered and it became clear which factors were more important for the prevention of heat loss.

  6. Selective classification and quantification model of C&D waste from material resources consumed in residential building construction.

    Science.gov (United States)

    Mercader-Moyano, Pilar; Ramírez-de-Arellano-Agudo, Antonio

    2013-05-01

    The unfortunate economic situation involving Spain and the European Union is, among other factors, the result of intensive construction activity over recent years. The excessive consumption of natural resources, together with the impact caused by the uncontrolled dumping of untreated C&D waste in illegal landfills have caused environmental pollution and a deterioration of the landscape. The objective of this research was to generate a selective classification and quantification model of C&D waste based on the material resources consumed in the construction of residential buildings, either new or renovated, namely the Conventional Constructive Model (CCM). A practical example carried out on ten residential buildings in Seville, Spain, enabled the identification and quantification of the C&D waste generated in their construction and the origin of the waste, in terms of the building material from which it originated and its impact for every m(2) constructed. This model enables other researchers to establish comparisons between the various improvements proposed for the minimization of the environmental impact produced by building a CCM, new corrective measures to be proposed in future policies that regulate the production and management of C&D waste generated in construction from the design stage to the completion of the construction process, and the establishment of sustainable management for C&D waste and for the selection of materials for the construction on projected or renovated buildings.

  7. WaterTransport in PEM Fuel Cells: Advanced Modeling, Material Selection, Testing and Design Optimization

    Energy Technology Data Exchange (ETDEWEB)

    J. Vernon Cole; Abhra Roy; Ashok Damle; Hari Dahr; Sanjiv Kumar; Kunal Jain; Ned Djilai

    2012-10-02

    Water management in Proton Exchange Membrane, PEM, Fuel Cells is challenging because of the inherent conflicts between the requirements for efficient low and high power operation. Particularly at low powers, adequate water must be supplied to sufficiently humidify the membrane or protons will not move through it adequately and resistance losses will decrease the cell efficiency. At high power density operation, more water is produced at the cathode than is necessary for membrane hydration. This excess water must be removed effectively or it will accumulate in the Gas Diffusion Layers, GDLs, between the gas channels and catalysts, blocking diffusion paths for reactants to reach the catalysts and potentially flooding the electrode. As power density of the cells is increased, the challenges arising from water management are expected to become more difficult to overcome simply due to the increased rate of liquid water generation relative to fuel cell volume. Thus, effectively addressing water management based issues is a key challenge in successful application of PEMFC systems. In this project, CFDRC and our partners used a combination of experimental characterization, controlled experimental studies of important processes governing how water moves through the fuel cell materials, and detailed models and simulations to improve understanding of water management in operating hydrogen PEM fuel cells. The characterization studies provided key data that is used as inputs to all state-of-the-art models for commercially important GDL materials. Experimental studies and microscopic scale models of how water moves through the GDLs showed that the water follows preferential paths, not branching like a river, as it moves toward the surface of the material. Experimental studies and detailed models of water and airflow in fuel cells channels demonstrated that such models can be used as an effective design tool to reduce operating pressure drop in the channels and the associated

  8. The Oil Point Method - A tool for indicative environmental evaluation in material and process selection

    DEFF Research Database (Denmark)

    Bey, Niki

    2000-01-01

    to three essential assessment steps, the method enables rough environmental evaluations and supports in this way material- and process-related decision-making in the early stages of design. In its overall structure, the Oil Point Method is related to Life Cycle Assessment - except for two main differences...... of environmental evaluation and only approximate information about the product and its life cycle. This dissertation addresses this challenge in presenting a method, which is tailored to these requirements of designers - the Oil Point Method (OPM). In providing environmental key information and confining itself...

  9. Strategies for increasing the efficiency of heterojunction organic solar cells: material selection and device architecture.

    Science.gov (United States)

    Heremans, Paul; Cheyns, David; Rand, Barry P

    2009-11-17

    Thin-film blends or bilayers of donor- and acceptor-type organic semiconductors form the core of heterojunction organic photovoltaic cells. Researchers measure the quality of photovoltaic cells based on their power conversion efficiency, the ratio of the electrical power that can be generated versus the power of incident solar radiation. The efficiency of organic solar cells has increased steadily in the last decade, currently reaching up to 6%. Understanding and combating the various loss mechanisms that occur in processes from optical excitation to charge collection should lead to efficiencies on the order of 10% in the near future. In organic heterojunction solar cells, the generation of photocurrent is a cascade of four steps: generation of excitons (electrically neutral bound electron-hole pairs) by photon absorption, diffusion of excitons to the heterojunction, dissociation of the excitons into free charge carriers, and transport of these carriers to the contacts. In this Account, we review our recent contributions to the understanding of the mechanisms that govern these steps. Starting from archetype donor-acceptor systems of planar small-molecule heterojunctions and solution-processed bulk heterojunctions, we outline our search for alternative materials and device architectures. We show that non-planar phthalocynanines have appealing absorption characteristics but also have reduced charge carrier transport. As a result, the donor layer needs to be ultrathin, and all layers of the device have to be tuned to account for optical interference effects. Using these optimization techniques, we illustrate cells with 3.1% efficiency for the non-planar chloroboron subphthalocyanine donor. Molecules offering a better compromise between absorption and carrier mobility should allow for further improvements. We also propose a method for increasing the exciton diffusion length by converting singlet excitons into long-lived triplets. By doping a polymer with a

  10. Compilation of minimum and maximum isotope ratios of selected elements in naturally occurring terrestrial materials and reagents

    Science.gov (United States)

    Coplen, T.B.; Hopple, J.A.; Böhlke, J.K.; Peiser, H.S.; Rieder, S.E.; Krouse, H.R.; Rosman, K.J.R.; Ding, T.; Vocke, R.D.; Revesz, K.M.; Lamberty, A.; Taylor, P.; De Bievre, P.

    2002-01-01

    Documented variations in the isotopic compositions of some chemical elements are responsible for expanded uncertainties in the standard atomic weights published by the Commission on Atomic Weights and Isotopic Abundances of the International Union of Pure and Applied Chemistry. This report summarizes reported variations in the isotopic compositions of 20 elements that are due to physical and chemical fractionation processes (not due to radioactive decay) and their effects on the standard atomic weight uncertainties. For 11 of those elements (hydrogen, lithium, boron, carbon, nitrogen, oxygen, silicon, sulfur, chlorine, copper, and selenium), standard atomic weight uncertainties have been assigned values that are substantially larger than analytical uncertainties because of common isotope abundance variations in materials of natural terrestrial origin. For 2 elements (chromium and thallium), recently reported isotope abundance variations potentially are large enough to result in future expansion of their atomic weight uncertainties. For 7 elements (magnesium, calcium, iron, zinc, molybdenum, palladium, and tellurium), documented isotope-abundance variations in materials of natural terrestrial origin are too small to have a significant effect on their standard atomic weight uncertainties. This compilation indicates the extent to which the atomic weight of an element in a given material may differ from the standard atomic weight of the element. For most elements given above, data are graphically illustrated by a diagram in which the materials are specified in the ordinate and the compositional ranges are plotted along the abscissa in scales of (1) atomic weight, (2) mole fraction of a selected isotope, and (3) delta value of a selected isotope ratio. There are no internationally distributed isotopic reference materials for the elements zinc, selenium, molybdenum, palladium, and tellurium. Preparation of such materials will help to make isotope ratio measurements among

  11. Digital Manufacturing of Selective Porous Barriers in Microchannels Using Multi-Material Stereolithography

    Directory of Open Access Journals (Sweden)

    Yong Tae Kim

    2018-03-01

    Full Text Available We have developed a sequential stereolithographic co-printing process using two different resins for fabricating porous barriers in microfluidic devices. We 3D-printed microfluidic channels with a resin made of poly(ethylene glycol diacrylate (MW = 258 (PEG-DA-258, a UV photoinitiator, and a UV sensitizer. The porous barriers were created within the microchannels in a different resin made of either PEG-DA (MW = 575 (PEG-DA-575 or 40% (w/w in water PEG-DA (MW = 700 (40% PEG-DA-700. We showed selective hydrogen ion diffusion across a 3D-printed PEG-DA-575 porous barrier in a cross-channel diffusion chip by observing color changes in phenol red, a pH indicator. We also demonstrated the diffusion of fluorescein across a 3D-printed 40% PEG-DA-700 porous barrier in a symmetric-channel diffusion chip by measuring fluorescence intensity changes across the porous barrier. Creating microfluidic chips with integrated porous barriers using a semi-automated 3D printing process shortens the design and processing time, avoids assembly and bonding complications, and reduces manufacturing costs compared to micromolding processes. We believe that our digital manufacturing method for fabricating selective porous barriers provides an inexpensive, simple, convenient and reproducible route to molecule delivery in the fields of molecular filtration and cell-based microdevices.

  12. Design Criteria, Operating Conditions, and Nickel-Iron Hydroxide Catalyst Materials for Selective Seawater Electrolysis.

    Science.gov (United States)

    Dionigi, Fabio; Reier, Tobias; Pawolek, Zarina; Gliech, Manuel; Strasser, Peter

    2016-05-10

    Seawater is an abundant water resource on our planet and its direct electrolysis has the advantage that it would not compete with activities demanding fresh water. Oxygen selectivity is challenging when performing seawater electrolysis owing to competing chloride oxidation reactions. In this work we propose a design criterion based on thermodynamic and kinetic considerations that identifies alkaline conditions as preferable to obtain high selectivity for the oxygen evolution reaction. The criterion states that catalysts sustaining the desired operating current with an overpotential seawater-mimicking electrolyte. The catalyst was synthesized by a solvothermal method and the activity, surface redox chemistry, and stability were tested electrochemically in alkaline and near-neutral conditions (borate buffer at pH 9.2) and under both fresh seawater conditions. The Tafel slope at low current densities is not influenced by pH or presence of chloride. On the other hand, the addition of chloride ions has an influence in the temporal evolution of the nickel reduction peak and on both the activity and stability at high current densities at pH 9.2. Faradaic efficiency close to 100 % under the operating conditions predicted by our design criteria was proven using in situ electrochemical mass spectrometry. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Corrosion studies on selected metallic materials for application in nuclear waste disposal containers

    International Nuclear Information System (INIS)

    Smailos, E.; Fiehn, B.; Gago, J.A.; Azkarate, I.

    1994-03-01

    In previous corrosion studies, carbon steels and the alloy Ti 99.8-Pd were identified as promising materials for heat-generating nuclear waste containers acting as a radionuclide barrier in a rock-salt repository. To characterize the long-term corrosion behaviour of these materials in more detail, a research programme including laboratory-scale and in-situ corrosion studies has been undertaken jointly by KfK and ENRESA/INASMET. In the period under review, gamma irradiation corrosion studies of up to about 6 months at 10 Gy/h and stress corrosion cracking studies at slow strain rates (10 -4 -10 -7 s -1 ) were performed on three preselected carbon steels in disposal relevant brines (NaCl-rich, MgCl 2 -rich) at 90 C and 150 C (TStE 355, TStE 460, 15 MnNi 6.3). Moreover, results were obtained from long-term in-situ corrosion studies (maximum test duration 9 years) conducted on carbon steel, Ti 99.8-Pd, Hastelloy C4, Ni-resist D4, and Si-cast iron in boreholes in the Asse salt mine. (orig./MM) [de

  14. Surface modification of plasmonic nanostructured materials with thiolated oligonucleotides in 10 seconds using selective microwave heating

    International Nuclear Information System (INIS)

    Abel, B.; Aslan, K.

    2012-01-01

    This study demonstrates the proof-of-principle of rapid surface modification of plasmonic nanostructured materials with oligonucleotides using low power microwave heating. Due to their interesting optical and electronic properties, silver nanoparticle films (SNFs, 2 nm thick) deposited onto glass slides were used as the model plasmonic nanostructured materials. Rapid surface modification of SNFs with oligonucleotides was carried out using two strategies (1) Strategy 1: for ss-oligonucleotides, surface hybridization and (2) Strategy 2: for ds-oligonucleotides, solution hybridization, where the samples were exposed to 10, 15, 30 and 60 seconds microwave heating. To assess the efficacy of our new rapid surface modification technique, identical experiments carried out without the microwave heating (i.e., conventional method), which requires 24 hours for the completion of the identical steps. It was found that SNFs can be modified with ss- and ds-oligonucleotides in 10 seconds, which typically requires several hours of incubation time for the chemisorption of thiol groups on to the planar metal surface using conventional techniques. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  15. Selecting novel material of vegetable pea for mechanical harvesting and canning

    Directory of Open Access Journals (Sweden)

    Kaigorodova Irina M.

    2016-01-01

    Full Text Available Breeding of novel pea cultivars is of significant interest in scope of increasing food shortages. The cultivars of new generation have to be highly technological and appropriate for mechanical treatment in all stages of planting. To provide higher outcome of plant products, pea is to be harvested for prolonged seasonal period, i.e. bred for conveyor usage. In this paper we presented the results of preliminary investigation of pea germplasm collection and studies on inheritance of flowering time in a series of crosses. We evaluated all hybrid progeny for duration of vegetation, lodging resistance and seed mass. Seven maturity groups were emphasized with most of obtained lines exhibiting an average duration of vegetation period measured as number of sterile nodes (11-15 for average fraction. As a result of this survey, the prospective genotypes for breeding new forms resistant to lodging and suitable for mechanical harvest were isolated. We propose a scheme of conveyor usage of new forms for sustainable delivery of stock for conversion industry. The obtained material is recommended for further improvement as the initial material for breeding.

  16. Comparison of design, materials selection and characterization of pacifiers produced in Brazil

    Directory of Open Access Journals (Sweden)

    Aliprandini P

    2011-02-01

    Full Text Available BackgroundA pacifier is an object designed for use by children aged twoweeks to around five years old. Although a convenient andan efficient alternative to children sucking their thumb, itsuse is highly questionable. With the advancement ofmedicine and technology, harms related to its use werediscovered and were related to poor development of theteeth. Furthermore, the use of some industrial rawmaterials may cause damage to the child’s health during thegrowing process.MethodThis study evaluates different models of pacifiers availableon the market, taking into consideration the design,materials and attendance to Brazilian Standards.ResultsThe Fourier Transform Infrared Spectroscopy (FTIR analysisof the five different models of pacifiers indicates the use ofdifferent materials. For models A, B and E, the nipple isbasically composed of silicone, while the guard is made ofpolycarbonate. For model C and D, the nipple is basicallycomposed of natural rubber, while the guard and the ringare made of polycarbonate. For model D and E, however,the presence of Bisphenol A (BPA was also used incomposition. For the tensile strength tests, only model Cwas disapproved.ConclusionSilicon and natural rubber satisfy the requirements fortechnical performance. However, this does not take intoaccount hygiene and toxicity as parameters for theselection, which are also important when considering childhealth.

  17. An Efficient approach for selective collection made by scavengers for transportation logistics of recyclable materials

    Directory of Open Access Journals (Sweden)

    Adelino Carlos Maccarini

    2014-01-01

    Full Text Available The advance of technology, associated to the increase in the production of recyclable waste due to the increase of consumption and population, has been led to a search for alternatives of management and minimization of this waste. A part of this recyclable material is collected by scavengers, who do it to guarantee their livelihood. Many of them face logistical difficulties in transportation, mainly when they have to walk long distances and the streets have high slopes. Therefore, to minimize these efforts, the purpose of this paper is to settle mobile warehouses to receive recyclable items, with trucks that receive in bulk all materials collected by the collectors, who will deliver them to someone who will be in the truck for weighing and subsequent payment to the collector. With the help of the Analysis of Variance – ANOVA, studies were made so that this receipt is a quick operation, with the historical record of each sampling in a spreadsheet and value calculations based on this description, thus minimizing errors in weighing in bulk and improving, in every collection, the system reliability.

  18. Material selection for prosthetics of defects of dentitions at patients with functional and inflammatory bowel diseases

    Directory of Open Access Journals (Sweden)

    Myalina Yu.N.

    2012-06-01

    Full Text Available Objective: To study clinical-morphological characteristics of parodontal diseases, markers of density of bone tissue and to define rational approaches to prosthetics of defects of dentitions in patients with colon diseases. Materials and methods: 55 patients with ulcerative colitis, even 80 with the syndrome of the irritable bowel syndrome with defects of dentitions, have been applied metallic, cement prostheses and having prostheses on the intraosseous of implants. Markers of bone metabolism in the blood serum and in the oral liquid, the proliferating activity of the epitheliocytes of periodontium have been evaluated according to the morphometric indices of the markers of the proliferation of ki-67, cyclein D1, the inhibitor of apoptosis of bcl-2 have been inspected. Results: Connection of intensity of periodontitis with the stage of colon disease has been stated. Metallic dental prostheses have been served as additional risk factors of development of parodontal diseases in patients with ulcerative colitis. Conclusion: The diagnostic value of the markers of proliferation has been determined in diagnostics of parodontal disease during the application of prostheses from different materials.

  19. Selection of candidate canister materials for high-level nuclear waste containment in a tuff repository

    International Nuclear Information System (INIS)

    McCright, R.D.; Weiss, H.; Juhas, M.C.; Logan, R.W.

    1983-11-01

    A repository located at Yucca Mountain at the Nevada Test Site is a potential site for permanent geological disposal of high-level nuclear waste. The repository can be located in a horizon in welded tuff, a volcanic rock, which is above the static water level at this site. The environmental conditions in this unsaturated zone are expected to be air and water vapor dominated for much of the containment period. Type 304L stainless steel is the reference material for fabricating canisters to contain the solid high-level wastes. Alternative stainless alloys are considered because of possible susceptibility of 304L to localized and stress forms of corrosion. For the reprocessed glass wastes, the canisters serve as the recipient for pouring the glass with the result that a sensitized microstructure may develop because of the times at elevated temperatures. Corrosion testing of the reference and alternative materials has begun in tuff-conditioned water and steam environments. 21 references, 8 figures, 8 tables

  20. High-temperature thermal storage systems for advanced solar receivers materials selections

    Science.gov (United States)

    Wilson, D. F.; Devan, J. H.; Howell, M.

    1990-01-01

    Advanced space power systems that use solar energy and Brayton or Stirling heat engines require thermal energy storage (TES) systems to operate continuously through periods of shade. The receiver storage units, key elements in both Brayton and Stirling systems, are designed to use the latent heat of fusion of phase-change materials (PCMs). The power systems under current consideration for near-future National Aeronautics and Space Administration space missions require working fluid temperatures in the 1100 to 1400 K range. The PCMs under current investigation that gave liquid temperatures within this range are the fluoride family of salts. However, these salts have low thermal conductivity, which causes large temperature gradients in the storage systems. Improvements can be obtained, however, with the use of thermal conductivity enhancements or metallic PCMs. In fact, if suitable containment materials can be found, the use of metallic PCMs would virtually eliminate the orbit associated temperature variations in TES systems. The high thermal conductivity and generally low volume change on melting of germanium and alloys based on silicon make them attractive for storage of thermal energy in space power systems. An approach to solving the containment problem, involving both chemical and physical compatibility, preparation of NiSi/NiSi2, and initial results for containment of germanium and NiSi/NiSi2, are presented.

  1. Selection of high temperature thermal energy storage materials for advanced solar dynamic space power systems

    Science.gov (United States)

    Lacy, Dovie E.; Coles-Hamilton, Carolyn; Juhasz, Albert

    1987-01-01

    Under the direction of NASA's Office of Aeronautics and Technology (OAST), the NASA Lewis Research Center has initiated an in-house thermal energy storage program to identify combinations of phase change thermal energy storage media for use with a Brayton and Stirling Advanced Solar Dynamic (ASD) space power system operating between 1070 and 1400 K. A study has been initiated to determine suitable combinations of thermal energy storage (TES) phase change materials (PCM) that result in the smallest and lightest weight ASD power system possible. To date the heats of fusion of several fluoride salt mixtures with melting points greater than 1025 K have been verified experimentally. The study has indicated that these salt systems produce large ASD systems because of their inherent low thermal conductivity and low density. It is desirable to have PCMs with high densities and high thermal conductivities. Therefore, alternate phase change materials based on metallic alloy systems are also being considered as possible TES candidates for future ASD space power systems.

  2. Thermal coupling and damage mechanisms of laser radiation on selected materials

    International Nuclear Information System (INIS)

    Schwirzke, F.; Jenkins, W.F.; Schmidt, W.R.

    1983-01-01

    High power laser beams interact with targets by a variety of thermal, impulse, and electrical effects. Energy coupling is considerably enhanced once surface electrical breakdown occurs. The laser heated plasma then causes surface damage via thermal evaporation, ion sputtering, and unipolar arcing. While the first two are purely thermal and mechanical effects, the last one, unipolar arcing, is an electrical plasma-surface interaction process which leads to crater formation, usually called laser-pitting, a process which was often observed but not well understood. Unipolar arcing occurs when a plasma of sufficiently high electron temperature interacts with a surface. Without an external voltage applied, many electrical micro-arcs burn between the surface and the plasma, driven by local variations of the sheath potential with the surface acting as both the cathode and anode. Laser induced unipolar arcing represents the most damaging and non-uniform plasma-surface interaction process since the energy available in the plasma concentrates towards the cathode spots. This causes cratering of the materials surface. The ejection of material in the form of small jets from the craters leads to ripples in the critical plasma density contour. This in turn contributes to the onset of plasma instabilities, small scale magnetic field generation and laser beam filamentation. The ejection of a plasma jet from the unipolar arc crater also causes highly localized shock waves to propagate into the target, softening it in the process. Thus, local surface erosion by unipolar arcing is much more severe than for uniform energy deposition

  3. THE ARECIBO LEGACY FAST ALFA SURVEY. IX. THE LEO REGION H I CATALOG, GROUP MEMBERSHIP, AND THE H I MASS FUNCTION FOR THE LEO I GROUP

    International Nuclear Information System (INIS)

    Stierwalt, Sabrina; Haynes, Martha P.; Giovanelli, Riccardo; Martin, Ann M.; Kent, Brian R.; Saintonge, Amelie; Karachentsev, Igor D.; Karachentseva, Valentina E.

    2009-01-01

    We present the catalog of H I sources extracted from the ongoing Arecibo Legacy Fast ALFA (ALFALFA) extragalactic H I line survey, found within the sky region bounded by 9 h 36 m h 36 m and +08 0 0 . The H I catalog presented here for this 118 deg 2 region is combined with the ones derived from surrounding regions also covered by the ALFALFA survey to examine the large-scale structure in the complex Leo region. Because of the combination of wide sky coverage and superior sensitivity, spatial and spectral resolution, the ALFALFA H I catalog of the Leo region improves significantly on the numbers of low H I mass sources as compared with those found in previous H I surveys. The H I mass function of the Leo I group presented here is dominated by low-mass objects: 45 of the 65 Leo I members have M H I 8 M-odot, yielding tight constraints on the low-mass slope of the Leo I H I mass function. The best-fit slope is α ≅ -1.41 + 0.2 - 0.1. A direct comparison between the ALFALFA H I line detections and an optical search of the Leo I region proves the advantage of the ALFALFA strategy in finding low-mass, gas-rich dwarfs. These results suggest the existence of a significant population of low surface brightness, gas-rich, yet still very low H I mass galaxies, and may reflect the same type of morphological segregation as is seen in the Local Group. While the low-mass end slope of the Leo I H I mass function is steeper than that determined for luminosity functions of the group, the slope still falls short of the values predicted by simulations of structure formation in the lambda cold dark matter paradigm.

  4. Materials

    CSIR Research Space (South Africa)

    Van Wyk, Llewellyn V

    2009-02-01

    Full Text Available . It is generally included as part of a structurally insulated panel (SIP) where the foam is sandwiched between external skins of steel, wood or cement. Cement composites Cement bonded composites are an important class of building materials. These products... for their stone buildings, including the Egyptians, Aztecs and Inca’s. As stone is a very dense material it requires intensive heating to become warm. Rocks were generally stacked dry but mud, and later cement, can be used as a mortar to hold the rocks...

  5. Application of miniaturized disk bend test technique for selection of optimum composition of candidate materials for fusion reactors

    International Nuclear Information System (INIS)

    Tsepelev, A.B.; Poymenov, I.L.

    1992-01-01

    An analysis of the potential of a miniaturized disk bend test (MDBT) technique for estimation of irradiated steel mechanical properties behaviour indicates promise in selecting candidate materials for nuclear applications. The advantages of the method are most clearly demonstrated when a large series of tests is needed. The tiny specimen size gives an additional advantage from the point of view of radiation material science. As an example of the MDBT potential, preliminary results of electron irradiation effects on Cr-Mn-W austenitic and Cr-W ferrite carbon and nitrogen steels are presented. It is shown that electron irradiation causes changes of the loading MDBT-curve form of the steels that most probably are connected with radiation-induced structure-phase transformations in the steels. (orig.)

  6. Material Selection for an Ultra High Strength Steel Component Based on the Failure Criteria of CrachFEM

    International Nuclear Information System (INIS)

    Kessler, L.; Beier, Th.; Werner, H.; Horstkott, D.; Dell, H.; Gese, H.

    2005-01-01

    An increasing use of combining more than one process step is noticed for coupling crash simulations with the results of forming operations -- mostly by inheriting the forming history like plastic strain and material hardening. Introducing a continuous failure model allows a further benefit of these coupling processes; it sometimes can even be the most attractive result of such a work. In this paper the algorithm CrachFEM for fracture prediction has been used to generate more benefit of the successive forming and crash simulations -- especially for ultra high strength steels. The choice and selection of the material grade in combination with the component design can therefore be done far before the prototyping might show an unsuccessful crash result; and in an industrial applicable manner

  7. Safety Standard for Hydrogen and Hydrogen Systems: Guidelines for Hydrogen System Design, Materials Selection, Operations, Storage and Transportation. Revision

    Science.gov (United States)

    1997-01-01

    The NASA Safety Standard, which establishes a uniform process for hydrogen system design, materials selection, operation, storage, and transportation, is presented. The guidelines include suggestions for safely storing, handling, and using hydrogen in gaseous (GH2), liquid (LH2), or slush (SLH2) form whether used as a propellant or non-propellant. The handbook contains 9 chapters detailing properties and hazards, facility design, design of components, materials compatibility, detection, and transportation. Chapter 10 serves as a reference and the appendices contained therein include: assessment examples; scaling laws, explosions, blast effects, and fragmentation; codes, standards, and NASA directives; and relief devices along with a list of tables and figures, abbreviations, a glossary and an index for ease of use. The intent of the handbook is to provide enough information that it can be used alone, but at the same time, reference data sources that can provide much more detail if required.

  8. Selection of highway routes for the shipment of radioactive materials within the Commonwealth of Virginia

    International Nuclear Information System (INIS)

    Hobeika, A.G.; Jamei, B.; Santoso, I.B.

    1986-01-01

    In this study Virginia Electric and Power Company proposed to ship limited quantities of irradiated nuclear fuel from Surry to North Anna in Virginia. Eight routes were considered as candidate routes for shipment. The objectives of this study are: To minimize the accidental-release radiation risk to people and property; and to maximize the community preparedness in terms of emergency response and evacuation capability. To determine the ''Preferred'' route and the alternative route for highway shipments of radioactive material, a conceptual approach was developed, based on the following three principles: Feasibility; Evaluation; and Choice. The feasibility of a candidate route is first established. Then all feasible routes are evaluated under the same criteria, which would lead to the choice of the best feasible route

  9. Material Evaluation and Process Optimization of CNT-Coated Polymer Powders for Selective Laser Sintering

    Directory of Open Access Journals (Sweden)

    Shangqin Yuan

    2016-10-01

    Full Text Available Multi-walled carbon nanotubes (CNTs as nano-reinforcements were introduced to facilitate the laser sintering process and enhance the thermal and mechanical properties of polymeric composites. A dual experimental-theoretical method was proposed to evaluate the processability and predict the process parameters of newly developed CNT-coated polyamide 12 (CNTs/PA12 powders. The thermal conductivity, melt viscosity, phase transition and temperature-dependent density and heat capacity of PA12 and CNTs/PA12 powders were characterized for material evaluation. The composite powders exhibited improved heat conduction and heat absorption compared with virgin polymer powders, and the stable sintering range of composite powders was extended and found to be favourable for the sintering process. The microstructures of sintered composites revealed that the CNTs remained at the powder boundaries and formed network architectures, which instantaneously induced the significant enhancements in tensile strength, elongation at break and toughness without sacrificing tensile modulus.

  10. Immobilisation of Cu, Pb and Zn in Scrap Metal Yard Soil Using Selected Waste Materials.

    Science.gov (United States)

    Kamari, A; Putra, W P; Yusoff, S N M; Ishak, C F; Hashim, N; Mohamed, A; Isa, I M; Bakar, S A

    2015-12-01

    Immobilisation of heavy metals in a 30-year old active scrap metal yard soil using three waste materials, namely coconut tree sawdust (CTS), sugarcane bagasse (SB) and eggshell (ES) was investigated. The contaminated soil was amended with amendments at application rates of 0 %, 1 % and 3 % (w/w). The effects of amendments on metal accumulation in water spinach (Ipomoea aquatica) and soil metal bioavailability were studied in a pot experiment. All amendments increased biomass yield and reduced metal accumulation in the plant shoots. The bioconcentration factor and translocation factor values of the metals were in the order of Zn > Cu > Pb. The addition of ES, an alternative source of calcium carbonate (CaCO3), has significantly increased soil pH and resulted in marked reduction in soil metal bioavailability. Therefore, CTS, SB and ES are promising low-cost immobilising agents to restore metal contaminated land.

  11. Selection of hardfacing material for components of the Indian Prototype Fast Breeder Reactor

    International Nuclear Information System (INIS)

    Bhaduri, A.K.; Indira, R.; Albert, S.K.; Rao, B.P.S.; Jain, S.C.; Asokkumar, S.

    2004-01-01

    Nickel-base hardfacing alloys have been chosen to replace cobalt-base alloys as hardfacing material for components of the Indian Prototype Fast Breeder Reactor, for minimising the dose rate to personnel during maintenance and decommissioning, and to reduce the shielding thickness required for component handling. Induced activity, dose rate and shielding computations showed that replacing cobalt-base alloys with nickel-base alloys for hardfacing of components would result in a marked reduction in both the dose rate from the components and the thickness of lead handling flasks. Long-term ageing studies on the nickel-base hardface deposits on austenitic stainless steel showed that the hardface deposit would retain adequate hardness at the end of the components' design service-life of 40 years of exposure at 823 K

  12. Geocenter variations derived from a combined processing of LEO- and ground-based GPS observations

    Science.gov (United States)

    Männel, Benjamin; Rothacher, Markus

    2017-08-01

    GNSS observations provided by the global tracking network of the International GNSS Service (IGS, Dow et al. in J Geod 83(3):191-198, 2009) play an important role in the realization of a unique terrestrial reference frame that is accurate enough to allow a detailed monitoring of the Earth's system. Combining these ground-based data with GPS observations tracked by high-quality dual-frequency receivers on-board low earth orbiters (LEOs) is a promising way to further improve the realization of the terrestrial reference frame and the estimation of geocenter coordinates, GPS satellite orbits and Earth rotation parameters. To assess the scope of the improvement on the geocenter coordinates, we processed a network of 53 globally distributed and stable IGS stations together with four LEOs (GRACE-A, GRACE-B, OSTM/Jason-2 and GOCE) over a time interval of 3 years (2010-2012). To ensure fully consistent solutions, the zero-difference phase observations of the ground stations and LEOs were processed in a common least-squares adjustment, estimating all the relevant parameters such as GPS and LEO orbits, station coordinates, Earth rotation parameters and geocenter motion. We present the significant impact of the individual LEO and a combination of all four LEOs on the geocenter coordinates. The formal errors are reduced by around 20% due to the inclusion of one LEO into the ground-only solution, while in a solution with four LEOs LEO-specific characteristics are significantly reduced. We compare the derived geocenter coordinates w.r.t. LAGEOS results and external solutions based on GPS and SLR data. We found good agreement in the amplitudes of all components; however, the phases in x- and z-direction do not agree well.

  13. Effect of irradiation on the microbiological status and flavouring materials of selected spices

    International Nuclear Information System (INIS)

    Farag, S.E.D.A.; Aziz, N.H.; Attia, E.S.A.

    1995-01-01

    Spices from Egyptian local markets were irradiated with different recommended doses (0, 5, 10, 20 and 30 kGy). The spices tested included dried leaves of marjoram (Majorana hortensis Moench), rhizomes of ginger (Zingiber officinale Roscoe) and powdered hot pepper (Capsicum annum L.). The study included the isolation and identification of micro-organisms in spices following their irradiation, as well as gas chromatographic (GLC) chemical analysis for the presence and structure of volatile oils, pungent and pigment materials. The results showed that hot pepper was contaminated more (9.2x10 5 /g) than marjoram (4.2x10 3 /g) and ginger (14.3x10 3 /g) with respect to total aerobic bacterial content. The total contents of moulds were 4.8x10 3 /g, 5.7x10 3 /g and 19x10 3 /g in the same spices, respectively, but the pathogenic moulds and bacterial strains differed according to the type of spice. Irradiation at 10, 20 and 30 kGy caused complete elimination of mirco-organisms, whereas 5 kGy was less effective. With the GLC method chosen 18 and 50 compounds could be detected in the extracts of marjoram and ginger, respectively; γ-terpinen and zingiberen being the major compounds in marjoram and ginger, respectively. A noticeable reduction was observed in the amount of terpenes present in irradiated marjoram; they were converted to monoterpensalcohols. Ginger was more sensitive to irradiation, especially at high doses, but moderate changes were detected at low doses (5 and 10 kGy). A slight, but significant effect on the capsaicin (pungent compound) in hot pepper was observed following irradiation, whereas no changes in total pigments resulted at any dose. These results prove that 10 kGy is a sufficiently high dose to eliminate the microorganisms in spices, causing only slight changes in the flavouring materials. (orig.)

  14. Effect of irradiation on the microbiological status and flavouring materials of selected spices

    Energy Technology Data Exchange (ETDEWEB)

    Farag, S.E.D.A. [National Centre for Radiation Research and Technology, Cairo (Egypt); Aziz, N.H. [National Centre for Radiation Research and Technology, Cairo (Egypt); Attia, E.S.A. [Egyptian Starch and Glucose Manufacturing Co., Cairo (Egypt)

    1995-12-31

    Spices from Egyptian local markets were irradiated with different recommended doses (0, 5, 10, 20 and 30 kGy). The spices tested included dried leaves of marjoram (Majorana hortensis Moench), rhizomes of ginger (Zingiber officinale Roscoe) and powdered hot pepper (Capsicum annum L.). The study included the isolation and identification of micro-organisms in spices following their irradiation, as well as gas chromatographic (GLC) chemical analysis for the presence and structure of volatile oils, pungent and pigment materials. The results showed that hot pepper was contaminated more (9.2x10{sup 5}/g) than marjoram (4.2x10{sup 3}/g) and ginger (14.3x10{sup 3}/g) with respect to total aerobic bacterial content. The total contents of moulds were 4.8x10{sup 3}/g, 5.7x10{sup 3}/g and 19x10{sup 3}/g in the same spices, respectively, but the pathogenic moulds and bacterial strains differed according to the type of spice. Irradiation at 10, 20 and 30 kGy caused complete elimination of mirco-organisms, whereas 5 kGy was less effective. With the GLC method chosen 18 and 50 compounds could be detected in the extracts of marjoram and ginger, respectively; {gamma}-terpinen and zingiberen being the major compounds in marjoram and ginger, respectively. A noticeable reduction was observed in the amount of terpenes present in irradiated marjoram; they were converted to monoterpensalcohols. Ginger was more sensitive to irradiation, especially at high doses, but moderate changes were detected at low doses (5 and 10 kGy). A slight, but significant effect on the capsaicin (pungent compound) in hot pepper was observed following irradiation, whereas no changes in total pigments resulted at any dose. These results prove that 10 kGy is a sufficiently high dose to eliminate the microorganisms in spices, causing only slight changes in the flavouring materials. (orig.)

  15. Technical report on material selection and processing guidelines for BWR [boiling water reactor] coolant pressure boundary piping: Final report

    International Nuclear Information System (INIS)

    Hazelton, W.S.; Koo, W.H.

    1988-01-01

    This report provides the technical bases for the NRC staff's revised recommended methods to control the intergranular stress corrosion cracking susceptibility of BWR piping. For piping that does not fully comply with the material selection, testing, and processing guideline combinations of this document, varying degrees of augmented inservice inspection are recommended. This revision also includes guidance and NRC staff recommendations (not requirements) regarding crack evaluation and weld overlay repair methods for long-term operation or for continuing interim operation of plants until a more permanent solution is implemented

  16. Oesophageal cancer in the Transkei. Determination of trace element concentrations in selected plant material by instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Renan, M.J.; Drennan, B.D.; Keddy, R.J.; Sellschop, J.P.F.

    1979-01-01

    The results of the analysis by instrumental neutron activation for the concentration of trace elements in plant materials from certain areas in the Transkei region of southern Africa are presented. These areas are selected for their characteristic high or low incidence of carcinoma of the oesophagus. To broaden the suite of elements for which analysed and to overcome some of the limitations of neutron activation analysis, certain other nuclear analyses and methods are suggested which, if utilized, would increase the number of elements determined, and so improve the information available. (author)

  17. Gadolinium(III) ion selective sensor using a new synthesized Schiff's base as a sensing material

    Energy Technology Data Exchange (ETDEWEB)

    Zamani, Hassan Ali, E-mail: haszamani@yahoo.com [Department of Applied Chemistry, Mashhad Branch, Islamic Azad University, Mashhad (Iran, Islamic Republic of); Mohammadhosseini, Majid [Department of Chemistry, Faculty of Basic Sciences, Shahrood Branch, Islamic Azad University, Shahrood (Iran, Islamic Republic of); Haji-Mohammadrezazadeh, Saeed [Department of Chemistry, Payame Noor University, Ardakan (Iran, Islamic Republic of); Faridbod, Farnoush [Endocrinology and Metabolism Research Center, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Ganjali, Mohammad Reza [Endocrinology and Metabolism Research Center, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Center of Excellence in Electrochemistry, Faculty of Chemistry, University of Tehran, Tehran (Iran, Islamic Republic of); Meghdadi, Soraia [Department of Chemistry, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Davoodnia, Abolghasem [Department of Chemistry, Faculty of Sciences, Mashhad Branch, Islamic Azad University, Mashhad (Iran, Islamic Republic of)

    2012-05-01

    According to a solution study which showed a selective complexation between N,N Prime -bis(methylsalicylidene)-2-aminobenzylamine (MSAB) and gadolinium ions, MSAB was used as a sensing element in construction of a gadolinium(III) ion selective electrode. Acetophenon (AP) was used as solvent mediator and sodium tetraphenyl borate (NaTPB) as an anion excluder. The electrode showed a good selectivity towards Gd(III) ions over a wide variety of cations tested. The constructed sensor displayed a Nernstian behavior (19.7 {+-} 0.3 mV/decade) in the concentration range of 1.0 Multiplication-Sign 10{sup -6} to 1.0 Multiplication-Sign 10{sup -2} mol L{sup -1} with detection limit of 5.0 Multiplication-Sign 10{sup -7} mol L{sup -1} and a short response time (< 10 s). The working pH range of the electrode was 3.5-10.1 and lifetime of the sensor was at least 10 weeks. Analysis of certified reference materials confirmed the accuracy of the proposed sensor. The electrode was successfully applied as an indicator electrode in gadolinium titration with EDTA. - Highlights: Black-Right-Pointing-Pointer A Gd{sup 3+}-PVC membrane sensor based on an ion carrier as sensing material is introduced. Black-Right-Pointing-Pointer This technique is very simple and it's not necessary to use sophisticated equipment. Black-Right-Pointing-Pointer This sensor shows good selectivity against other metal ions.

  18. Glass and Glass-Ceramic Materials from Simulated Composition of Lunar and Martian Soils: Selected Properties and Potential Applications

    Science.gov (United States)

    Ray, C. S.; Sen, S.; Reis, S. T.; Kim, C. W.

    2005-01-01

    In-situ resource processing and utilization on planetary bodies is an important and integral part of NASA's space exploration program. Within this scope and context, our general effort is primarily aimed at developing glass and glass-ceramic type materials using lunar and martian soils, and exploring various applications of these materials for planetary surface operations. Our preliminary work to date have demonstrated that glasses can be successfully prepared from melts of the simulated composition of both lunar and martian soils, and the melts have a viscosity-temperature window appropriate for drawing continuous glass fibers. The glasses are shown to have the potential for immobilizing certain types of nuclear wastes without deteriorating their chemical durability and thermal stability. This has a direct impact on successfully and economically disposing nuclear waste generated from a nuclear power plant on a planetary surface. In addition, these materials display characteristics that can be manipulated using appropriate processing protocols to develop glassy or glass-ceramic magnets. Also discussed in this presentation are other potential applications along with a few selected thermal, chemical, and structural properties as evaluated up to this time for these materials.

  19. A methodology to guide the selection of composite materials in a wind turbine rotor blade design process

    Science.gov (United States)

    Bortolotti, P.; Adolphs, G.; Bottasso, C. L.

    2016-09-01

    This work is concerned with the development of an optimization methodology for the composite materials used in wind turbine blades. Goal of the approach is to guide designers in the selection of the different materials of the blade, while providing indications to composite manufacturers on optimal trade-offs between mechanical properties and material costs. The method works by using a parametric material model, and including its free parameters amongst the design variables of a multi-disciplinary wind turbine optimization procedure. The proposed method is tested on the structural redesign of a conceptual 10 MW wind turbine blade, its spar caps and shell skin laminates being subjected to optimization. The procedure identifies a blade optimum for a new spar cap laminate characterized by a higher longitudinal Young's modulus and higher cost than the initial one, which however in turn induce both cost and mass savings in the blade. In terms of shell skin, the adoption of a laminate with intermediate properties between a bi-axial one and a tri-axial one also leads to slight structural improvements.

  20. Mechanical Properties of Ti-6Al-4V Octahedral Porous Material Unit Formed by Selective Laser Melting

    Directory of Open Access Journals (Sweden)

    Jianfeng Sun

    2012-01-01

    Full Text Available The Ti-6Al-4V octahedral porous material unit is designed to calculate its load. In this paper, ANSYS is adopted for the load simulation of the unit. And a simplified model of dimensional theoretical calculation is established, by which the analytical equation of the fracture load is obtained and the calculation of the load of Ti-6Al-4V is completed. Moreover, selective laser melting is adopted in processing the Ti-6Al-4V porous material unit. The experimental value of fracture load of this material is obtained through compression experiment. The results show that the simulation curves approximate the variation tendency of the elastic deformation of the compression curves; the curves of theoretical calculation approximate the general variation tendency; and the experimental value of fracture load is very close to the theoretical value. Therefore, the theoretical prediction accuracy of fracture load is high, which lays the foundation for the mechanical properties of the octahedral porous material.