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Sample records for refractory alloys final

  1. Pack cementation diffusion coatings for Fe-base and refractory alloys. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Rapp, R.A. [Ohio State Univ., Columbus, OH (United States). Dept. of Materials Science and Engineering

    1998-03-10

    With the aid of computer-assisted calculations of the equilibrium vapor pressures in halide-activated cementation packs, processing conditions have been identified and experimentally verified for the codeposition of two or more alloying elements in a diffusion coating on a variety of steels and refractory metal alloys. A new comprehensive theory to treat the multi-component thermodynamic equilibria in the gas phase for several coexisting solid phases was developed and used. Many different processes to deposit various types of coatings on several types of steels were developed: Cr-Si codeposition for low- or medium-carbon steels, Cr-Al codeposition on low-carbon steels to yield either a Kanthal-type composition (Fe-25Cr-4Al in wt.%) or else a (Fe, Cr){sub 3}Al surface composition. An Fe{sub 3}Al substrate was aluminized to achieve an FeAl surface composition, and boron was also added to ductilize the coating. The developmental Cr-lean ORNL alloys with exceptional creep resistance were Cr-Al coated to achieve excellent oxidation resistance. Alloy wires of Ni-base were aluminized to provide an average composition of Ni{sub 3}Al for use as welding rods. Several different refractory metal alloys based on Cr-Cr{sub 2}Nb have been silicided, also with germanium additions, to provide excellent oxidation resistance. A couple of developmental Cr-Zr alloys were similarly coated and tested.

  2. Radiation Effects in Refractory Alloys

    Science.gov (United States)

    Zinkle, Steven J.; Wiffen, F. W.

    2004-02-01

    In order to achieve the required low reactor mass per unit electrical power for space reactors, refractory alloys are essential due to their high operating temperature capability that in turn enables high thermal conversion efficiencies. One of the key issues associated with refractory alloys is their performance in a neutron irradiation environment. The available radiation effects data are reviewed for alloys based on Mo, W, Re, Nb and Ta. The largest database is associated with Mo alloys, whereas Re, W and Ta alloys have the least available information. Particular attention is focused on Nb-1Zr, which is a proposed cladding and structural material for the reactor in the Jupiter Icy Moons Orbiter (JIMO) project. All of the refractory alloys exhibit qualitatively similar temperature-dependent behavior. At low temperatures up to ~0.3TM, where TM is the melting temperature, the dominant effect of radiation is to produce pronounced radiation hardening and concomitant loss of ductility. The radiation hardening also causes a dramatic decrease in the fracture toughness of the refractory alloys. These low temperature radiation effects occur at relatively low damage levels of ~0.1 displacement per atom, dpa (~2×1024 n/m2, E>0.1 MeV). As a consequence, operation at low temperatures in the presence of neutron irradiation must be avoided for all refractory alloys. At intermediate temperatures (0.3 to 0.6 TM), void swelling and irradiation creep are the dominant effects of irradiation. The amount of volumetric swelling associated with void formation in refractory alloys is generally within engineering design limits (>10 dpa). Very little experimental data exist on irradiation creep of refractory alloys, but data for other body centered cubic alloys suggest that the irradiation creep will produce negligible deformation for near-term space reactor applications.

  3. SINTERED REFRACTORY TUNGSTEN ALLOYS. Gesinterte hochschmelzende wolframlegierungen

    Energy Technology Data Exchange (ETDEWEB)

    Kieffer, R.; Sedlatschek, K.; Braun, H.

    1971-12-15

    Dependence of the melting point of the refractory metals on their positions in the periodic system - alloys of tungsten with other refractory metals - sintering of the alloys - processing of the alloys - technological properties.

  4. Alloy design for intrinsically ductile refractory high-entropy alloys

    Science.gov (United States)

    Sheikh, Saad; Shafeie, Samrand; Hu, Qiang; Ahlström, Johan; Persson, Christer; Veselý, Jaroslav; Zýka, Jiří; Klement, Uta; Guo, Sheng

    2016-10-01

    Refractory high-entropy alloys (RHEAs), comprising group IV (Ti, Zr, Hf), V (V, Nb, Ta), and VI (Cr, Mo, W) refractory elements, can be potentially new generation high-temperature materials. However, most existing RHEAs lack room-temperature ductility, similar to conventional refractory metals and alloys. Here, we propose an alloy design strategy to intrinsically ductilize RHEAs based on the electron theory and more specifically to decrease the number of valence electrons through controlled alloying. A new ductile RHEA, Hf0.5Nb0.5Ta0.5Ti1.5Zr, was developed as a proof of concept, with a fracture stress of close to 1 GPa and an elongation of near 20%. The findings here will shed light on the development of ductile RHEAs for ultrahigh-temperature applications in aerospace and power-generation industries.

  5. Kinetics and Structure of Refractory Compounds and AlloysObtained by Mechanical Alloying

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Refractory compounds are material with interesting properties for structural applications. However, the processing of such material is a great challenge because of their high melting temperature and limited ductility. Mechanical alloying is a novel technique of producing refractory compounds with specific properties. Kinetical and structural peculiarities of refractory compounds and alloys obtained by mechanical alloying are discussed.

  6. Refractory alloy technology for space nuclear power applications

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, R.H. Jr.; Hoffman, E.E. (eds.)

    1984-01-01

    Purpose of this symposium is twofold: (1) to review and document the status of refractory alloy technology for structural and fuel-cladding applications in space nuclear power systems, and (2) to identify and document the refractory alloy research and development needs for the SP-100 Program in both the short and the long term. In this symposium, an effort was made to recapture the space reactor refractory alloy technology that was cut off in midstream around 1973 when the national space nuclear reactor program began in the early 1960s, was terminated. The six technical areas covered in the program are compatibility, processing and production, welding and component fabrication, mechanical and physical properties, effects of irradiation, and machinability. The refractory alloys considered are niobium, molybdenum, tantalum, and tungsten. Thirteen of the 14 pages have been abstracted separately. The remaining paper summarizes key needs for further R and D on refractory alloys. (DLC)

  7. Thermal aging effects in refractory metal alloys

    Science.gov (United States)

    Stephens, Joseph R.

    1987-01-01

    The alloys of niobium and tantalum are attractive from a strength and compatibility viewpoint for high operating temperatures required in materials for fuel cladding, liquid metal transfer, and heat pipe applications in space power systems that will supply from 100 kWe to multi-megawatts for advanced space systems. To meet the system requirements, operating temperatures ranging from 1100 to 1600 K have been proposed. Expected lives of these space power systems are from 7 to 10 yr. A program is conducted at NASA Lewis to determine the effects of long-term, high-temperature exposure on the microstructural stability of several commercial tantalum and niobium alloys. Variables studied in the investigation include alloy composition, pre-age annealing temperature, aging time, temperature, and environment (lithium or vacuum), welding, and hydrogen doping. Alloys are investigated by means of cryogenic bend tests and tensile tests. Results show that the combination of tungsten and hafnium or zirconium found in commercial alloys such as T-111 and Cb-752 can lead to aging embrittlement and increased susceptibility to hydrogen embrittlement of ternary and more complex alloys. Modification of alloy composition helps to eliminate the embrittlement problem.

  8. Processing of Refractory Metal Alloys for JOYO Irradiations

    Energy Technology Data Exchange (ETDEWEB)

    RF Luther; ME Petrichek

    2006-02-21

    This is a summary of the refractory metal processing experienced by candidate Prometheus materiats as they were fabricated into specimens destined for testing within the JOYO test reactor, ex-reactor testing at Oak Ridge National Laboratory (ORNL), or testing within the NRPCT. The processing is described for each alloy from the point of inception to the point where processing was terminated due to the cancellation of Naval Reactor's involvement in the Prometheus Project. The alloys included three tantalum-base alloys (T-111, Ta-10W, and ASTAR-811C), a niobium-base alloy, (FS-85), and two molybdenum-rhenium alloys, one containing 44.5 w/o rhenium, and the other 47.5 w/o rhenium. Each of these alloys was either a primary candidate or back-up candidate for cladding and structural applications within the space reactor. Their production was intended to serve as a forerunner for large scale production ingots that were to be procured from commercial refractory metal vendors such as Wah Chang.

  9. Directed Light Fabrication of Refractory Metals and Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Fonseca, J.C.; Lewis, G.K.; Dickerson, P.G.; Nemec, R.B.

    1999-05-14

    This report covers work performed under Order No. FA0000020 AN Contract DE-AC12-76SN00052 for deposition of refractory pure metals and alloys using the Directed Light Fabrication (DLF) process and represents the progress in depositing these materials through September 1998. In extending the DLF process technology to refractory metals for producing fully dense, structurally sound deposits, several problems have become evident. 1. Control of porosity in DLF-deposited refractory metal is difficult because of gases, apparently present in commercially purchased refractory metal powder starting materials. 2. The radiant heat from the molten pool during deposition melts the DLF powder feed nozzle. 3. The high reflectivity of molten refractory metals, at the Nd-YAG laser wavelength (1.06{micro}m), produces damaging back reflections to the optical train and fiber optic delivery system that can terminate DLF processing. 4. The current limits on the maximum available laser power to prevent back reflection damage limit the parameter range available for densification of refractory metals. The work to date concentrated on niobium, W-25Re, and spherodized tungsten. Niobium samples, made from hydride-dehydride powder, had minimal gas porosity and the deposition parameters were optimized; however, test plates were not made at this time. W-25Re samples, containing sodium and potassium from a precipitation process, were made and porosity was a problem for all samples although minimized with some process parameters. Deposits made from potassium reduced tungsten that was plasma spherodized were made with minimized porosity. Results of this work indicate that further gas analysis of starting powders and de-gassing of starting powders and/or gas removal during deposition of refractory metals is required.

  10. Directed light fabrication of refractory metals and alloys

    Energy Technology Data Exchange (ETDEWEB)

    Fonseca, J.C.; Lewis, G.K.; Dickerson, P.G.; Nemec, R.B.

    1999-05-30

    This report covers deposition of refractory pure metals and alloys using the Directed Light Fabrication (DLF) process and represents progress in depositing these materials through September 1998. In extending the DLF process technology to refractory metals for producing fully dense, structurally sound deposits, several problems have become evident. (1) Control of porosity in DLF-deposited refractory metal is difficult because of gases, apparently present in commercially purchased refractory metal powder starting materials. (2) The radiant heat from the molten pool during deposition melts the DLF powder feed nozzle. (3) The high reflectivity of molten refractory metals, at the Nd-YAG laser wavelength (1.06{micro}m), produces damaging back reflections to the optical train and fiber optic delivery system that can terminate DLF processing. (4) The current limits on the maximum available laser power to prevent back reflection damage limit the parameter range available for densification of refractory metals. The work to date concentrated on niobium, W-25Re, and spherodized tungsten. Niobium samples, made from hydride-dehydride powder, had minimal gas porosity and the deposition parameters were optimized; however, test plates were not made at this time. W-25Re samples, containing sodium and potassium from a precipitation process, were made and porosity was a problem for all samples although minimized with some process parameters. Deposits made from potassium reduced tungsten that was plasma spherodized were made with minimized porosity. Results of this work indicate that further gas analysis of starting powders and de-gassing of starting powders and/or gas removal during deposition of refractory metals is required.

  11. Modeling of high entropy alloys of refractory elements

    Energy Technology Data Exchange (ETDEWEB)

    Grosso, M.F. del, E-mail: delgrosso@tandar.cnea.gov.ar [Gcia. Investigacion y Aplicaciones, CNEA, Av. Gral Paz 1499, (B1650KNA), San Martin (Argentina); GCMM, UTN, FRG Pacheco, Av. H. Yrigoyen 288, Gral. Pacheco (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas, CONICET (Argentina); Bozzolo, G. [Loyola University Maryland, 4501 N. Charles St., Baltimore, MD 21210 (United States); Mosca, H.O. [Gcia. Investigacion y Aplicaciones, CNEA, Av. Gral Paz 1499, (B1650KNA), San Martin (Argentina); GCMM, UTN, FRG Pacheco, Av. H. Yrigoyen 288, Gral. Pacheco (Argentina)

    2012-08-15

    Reverting the traditional process of developing new alloys based on one or two single elements with minority additions, the study of high entropy alloys (HEA) (equimolar combinations of many elements) has become a relevant and interesting new field of research due to their tendency to form solid solutions with particular properties in the absence of intermetallic phases. Theoretical or modeling studies at the atomic level on specific HEA, describing the formation, structure, and properties of these alloys are limited due to the large number of constituents involved. In this work we focus on HEA with refractory elements showing atomistic modeling results for W-Nb-Mo-Ta and W-Nb-Mo-Ta-V HEA, for which experimental background exists. An atomistic modeling approach is applied for the determination of the role of each element and identification of the interactions and features responsible for the transition to the high entropy regime. Results for equimolar alloys of 4 and 5 refractory elements, for which experimental results exist, are shown. A straightforward algorithm is introduced to interpret the transition to the high entropy regime.

  12. Microstructure and nano-mechanical property of cold spray Co-base refractory alloy coating

    Institute of Scientific and Technical Information of China (English)

    Yongli LIANG; Bi SHI; Xiaoping YANG; Junbao ZHANG; Xianming MENG

    2011-01-01

    Co-base refractory alloy coating was prepared on carbon steel substrate by cold spray technology; microstructure and nano-mechenical property were examined by scanning electron microscope (SEM) and nano indenter individually. The results showed that about 250 μm Co-base refractory alloy coating could be deposited on steel substrate by cold spray technique, interface between coating and substrate was combined well, and the refractory alloy particle had a significant plastic deformation during deposition process; mixing Ni powders into Co-base refractory alloy powders could increase the density and decrease the nano-hardness of coating, the nano-hardness and elastic modulus of refractory alloy coating was higher than 6 GPa and 160 GPa, respectively.

  13. Microstructure and Elevated Temperature Properties of a Refractory TaNbHfZrTi Alloy

    Science.gov (United States)

    2012-01-24

    alloy was prepared by vacuum arc melting of the equimolar mixtures of the corresponding elements. Titanium, zirconium, and hafnium were in the form of...AND ELEVATED TEMPERATURE PROPERTIES OF A REFRACTORY TaNbHfZrTi ALLOY (POSTPRINT) 5a. CONTRACT NUMBER In-house 5b. GRANT NUMBER 5c. PROGRAM...6260-2. 14. ABSTRACT Compression properties of a refractory multicomponent alloy , Ta20Nb20Hf20Zr20Ti20, were determined in the temperature range

  14. Cost Estimate for Molybdenum and Tantalum Refractory Metal Alloy Flow Circuit Concepts

    Science.gov (United States)

    Hickman, Robert R.; Martin, James J.; Schmidt, George R.; Godfroy, Thomas J.; Bryhan, A.J.

    2010-01-01

    The Early Flight Fission-Test Facilities (EFF-TF) team at NASA Marshall Space Flight Center (MSFC) has been tasked by the Naval Reactors Prime Contract Team (NRPCT) to provide a cost and delivery rough order of magnitude estimate for a refractory metal-based lithium (Li) flow circuit. The design is based on the stainless steel Li flow circuit that is currently being assembled for an NRPCT task underway at the EFF-TF. While geometrically the flow circuit is not representative of a final flight prototype, knowledge has been gained to quantify (time and cost) the materials, manufacturing, fabrication, assembly, and operations to produce a testable configuration. This Technical Memorandum (TM) also identifies the following key issues that need to be addressed by the fabrication process: Alloy selection and forming, cost and availability, welding, bending, machining, assembly, and instrumentation. Several candidate materials were identified by NRPCT including molybdenum (Mo) alloy (Mo-47.5 %Re), tantalum (Ta) alloys (T-111, ASTAR-811C), and niobium (Nb) alloy (Nb-1 %Zr). This TM is focused only on the Mo and Ta alloys, since they are of higher concern to the ongoing effort. The initial estimate to complete a Mo-47%Re system ready for testing is =$9,000k over a period of 30 mo. The initial estimate to complete a T-111 or ASTAR-811C system ready for testing is =$12,000k over a period of 36 mo.

  15. Pumped lithium loop test to evaluate advanced refractory metal alloys and simulated nuclear fuel elements

    Science.gov (United States)

    Brandenburf, G. P.; Hoffman, E. E.; Smith, J. P.

    1974-01-01

    The performance was determined of refractory metal alloys and uranium nitride fuel element specimens in flowing 1900F (1083C) lithium. The results demonstrate the suitability of the selected materials to perform satisfactorily from a chemical compatibility standpoint.

  16. Direct Metal Deposition of Refractory High Entropy Alloy MoNbTaW

    Science.gov (United States)

    Dobbelstein, Henrik; Thiele, Magnus; Gurevich, Evgeny L.; George, Easo P.; Ostendorf, Andreas

    Alloying of refractory high entropy alloys (HEAs) such as MoNbTaW is usually done by vacuum arc melting (VAM) or powder metallurgy (PM) due to the high melting points of the elements. Machining to produce the final shape of parts is often needed after the PM process. Casting processes, which are often used for aerospace components (turbine blades, vanes), are not possible. Direct metal deposition (DMD) is an additive manufacturing technique used for the refurbishment of superalloy components, but generating these components from the bottom up is also of current research interest. MoNbTaW possesses high yield strength at high temperatures and could be an alternative to state-of-the-art materials. In this study, DMD of an equimolar mixture of elemental powders was performed with a pulsed Nd:YAG laser. Single wall structures were built, deposition strategies developed and the microstructure of MoNbTaW was analyzed by back scattered electrons (BSE) and energy dispersive X-ray (EDX) spectroscopy in a scanning electron microscope. DMD enables the generation of composition gradients by using dynamic powder mixing instead of pre-alloyed powders. However, the simultaneous handling of several elemental or pre-alloyed powders brings new challenges to the deposition process. The influence of thermal properties, melting point and vapor pressure on the deposition process and chemical composition will be discussed.

  17. Approaches to oxidation-resistant refractory metal alloys

    OpenAIRE

    Wright, I; Nagarajan, V.

    1993-01-01

    The focus of the research reported here was on the design of high-temperature alloys which would form protective SiO2 and Al2O3 scales on exposure to high-temperature, oxidizing environments. One way to promote the growth of such scales is to incorporate sufficient amounts of Si or Al in the alloy substrate ; typically, additions of approximately 35 to 45 weight percent (all alloy compositions are given in weight percent unless explicitly stated otherwise) of Si or Al would be required to for...

  18. Effect of CaF2 on Interfacial Phenomena of High Alumina Refractories with Al Alloy

    Science.gov (United States)

    Koshy, Pramod; Gupta, Sushil; Sahajwalla, Veena; Edwards, Phil

    2008-08-01

    An experimental study was conducted to investigate the interfacial phenomena between Al-alloy and industrial grade high alumina refractories containing varying contents of CaF2 at 1250 °C. Interfacial reaction products and phases formed in the heat-treated refractory samples were characterized using electron probe microanalysis (EPMA) and X-ray diffraction (XRD), respectively, while interfacial phenomena including dynamic wetting behavior were analyzed using the sessile drop technique. Refractories containing less than 5 wt pct CaF2 showed good resistance to reactions with the molten alloy, due to the dominance of corundum, and the presence of anorthite at the interface. However, with a further increase in the additive content, a glassy matrix of anorthite with CaF2 was formed. Formation of this phase significantly increased the intensity of reactions resulting in the buildup of an interfacial layer. The study thus revealed the strong catalytic effect of CaF2 on reactions of high alumina refractories with Al-alloy.

  19. Dendritic solidification and thermal expansion of refractory Nb-Zr alloys investigated by electrostatic levitation

    Science.gov (United States)

    Yang, S. J.; Hu, L.; Wang, L.; Wei, B.

    2017-05-01

    The dendritic growth and thermal expansion of isomorphous refractory Nb-5%Zr, Nb-10%Zr, and Nb-15%Zr alloys were studied by electrostatic levitation technique. The obtained maximum undercoolings for the three alloys were 534 (0.2 T L), 498 (0.19 T L), and 483 K (0.18 T L), respectively. Within these undercooling ranges, the dendritic growth velocities of the three alloys all exhibited power laws, and achieved 38.5, 34.0, and 27.1 m s-1 at each maximum undercooling. The microstructures were characterized by coarse dendrites at small undercooling, while they transformed into refined dendrites under large undercooling condition. In addition, the measured thermal expansion coefficients of solid Nb-Zr alloys increased linearly with temperature. The values at liquid state were more than double of those at solid state, which also displayed linear dependence on temperature.

  20. Integrated Design and Rapid Development of Refractory Metal Based Alloys for Fossil Energy Applications

    Energy Technology Data Exchange (ETDEWEB)

    Dogan, O.N.; King, P.E.; Gao, M.C.

    2008-07-01

    One common barrier in the development of new technologies for future energy generating systems is insufficiency of existing materials at high temperatures (>1150oC) and aggressive atmospheres (e.g., steam, oxygen, CO2). To overcome this barrier, integrated design methodology will be applied to the development of refractory metal based alloys. The integrated design utilizes the multi-scale computational methods to design materials for requirements of processing and performance. This report summarizes the integrated design approach to the alloy development and project accomplishments in FY 2008.

  1. Effect of Silica on High-Temperature Interfacial Phenomena of Monolithic Refractories with Al Alloy

    Science.gov (United States)

    Koshy, Pramod; Gupta, Sushil; Sahajwalla, Veena; Edwards, Phil

    2008-04-01

    An experimental study was conducted to study the interfacial phenomena between monolithic refractories and Al alloy at 1250 °C. Dynamic contact angles of monolithic substrates with varying silica levels were measured using the sessile drop technique, while phases present in the preheated monolithic samples and interfacial reaction products were characterized using X-ray diffraction (XRD) and an electron probe microanalyzer (EPMA). The contact angles in the Al alloy/silica system were found to change much more rapidly as compared to that of the alloy/alumina system, clearly demonstrating the high wetting tendency of silica. Under the tested conditions, the corundum phase forms at the interface while Mg was found to vaporize from the alloy and accumulate at the bottom of the monolithic substrate. Both these phenomena are shown to influence the intensity of contact angle variations with time and, thereby, the wetting behavior of monolithic substrates. Based on dynamic contact angles and equilibrium calculations, monolithic refractories are further classified into three groups, such that the wetting characteristics of those with compositions in the ranges of 0 to 25 pct, 25 to 45 pct, and >45 pct silica were shown to be dictated by the presence of corundum, mullite, and free silica, respectively, as the predominant phase.

  2. Determination of the transition to the high entropy regime for alloys of refractory elements

    Energy Technology Data Exchange (ETDEWEB)

    Grosso, Mariela F. del [Gerencia de Investigacion y Aplicaciones, Comision Nacional de Energia Atomica, Av. Gral. Paz 1499 (B1650KNA), San Martin (Argentina); CONICET, Buenos Aires (Argentina); Grupo de Caracterizacion y Modelizacion de Materiales, UTN, FRGP, H. Yrigoyen 288, (B1617FRG) Gral. Pacheco (Argentina); Bozzolo, Guillermo, E-mail: guille_bozzolo@yahoo.com [Loyola University Maryland, 4501 N. Charles St., Baltimore, MD 21210 (United States); Mosca, Hugo O. [Gerencia de Investigacion y Aplicaciones, Comision Nacional de Energia Atomica, Av. Gral. Paz 1499 (B1650KNA), San Martin (Argentina); Grupo de Caracterizacion y Modelizacion de Materiales, UTN, FRGP, H. Yrigoyen 288, (B1617FRG) Gral. Pacheco (Argentina)

    2012-09-05

    Highlights: Black-Right-Pointing-Pointer Atomistic modeling using a quantum approximate method for the energetics. Black-Right-Pointing-Pointer Modeling of the phase structure of high entropy alloys of refractory elements. Black-Right-Pointing-Pointer Comparison of modeled structure with experimental results for five-element alloys. Black-Right-Pointing-Pointer Determination of bulk properties of transitional chains from 4 to 5 element alloys. Black-Right-Pointing-Pointer Introduction of an algorithm to aid in the design of high entropy alloys. - Abstract: The development of high entropy alloys is currently limited to experimental work aimed at the determination of specific compositions that exhibit particular properties. The main feature of these alloys is their particular phase structure, which tends to be a continuous solid solution in spite of the large number of constituents which would otherwise form a large number of intermetallic phases. While it is known that equimolar concentrations and large number of elements are two necessary conditions for achieving high entropy behavior, not much is known regarding the transition to this regime in the presence of specific elements. Such knowledge would be useful when determining alloy compositions, as it would set boundaries for the necessary concentrations of each element in experimental situations. In this work, results of a computational modeling effort are presented, where a recently developed 5-element high entropy alloy of refractory elements is used as the foundation needed to examine such transition and determine the necessary lower bounds for the concentration of each element. Details of the phase structure of the quaternary combinations of W, Nb, Mo, Ta and V as they evolve upon the addition of a fifth element are discussed. The results are compared to the experimental case for the case of V added to W-Nb-Mo-Ta. Using these examples as a reference, the concept of critical concentrations for each element

  3. Alloying effects of refractory elements in the dislocation of Ni-based single crystal superalloys

    Directory of Open Access Journals (Sweden)

    Shiyu Ma

    2016-12-01

    Full Text Available The alloying effects of W, Cr and Re in the [100] (010 edge dislocation cores (EDC of Ni-based single crystal superalloys are investigated using first-principles based on the density functional theory (DFT. The binding energy, Mulliken orbital population, density of states, charge density and radial distribution functions are discussed, respectively. It is clearly demonstrated that the addition of refractory elements improves the stability of the EDC systems. In addition, they can form tougher bonds with their nearest neighbour (NN Ni atoms, which enhance the mechanical properties of the Ni-based single crystal superalloys. Through comparative analysis, Cr-doped system has lower binding energy, and Cr atom has evident effect to improve the systemic stability. However, Re atom has the stronger alloying effect in Ni-based single crystal superalloys, much more effectively hindering dislocation motion than W and Cr atoms.

  4. Supporting data for senary refractory high-entropy alloy CrxMoNbTaVW

    Directory of Open Access Journals (Sweden)

    B. Zhang

    2015-12-01

    Full Text Available This data article is related to the research paper entitled “senary refractory high-entropy alloy CrxMoNbTaVW [1]”. In this data article, the pseudo-binary Cr-MoNbTaVW phase diagram is presented to show the impact of Cr content to the senary Cr-MoNbTaVW alloy system; the sub-lattice site fractions are presented to show the disordered property of the Cr-MoNbTaVW BCC structures; the equilibrium and Scheil solidification results with the actual sample elemental compositions are presented to show the thermodynamic information of the melted/solidified CrxMoNbTaVW samples; and the raw EDS scan data of the arc-melted CrxMoNbTaVW samples are also provided.

  5. Liquid Supercoolability and Synthesis Kinetics of Quinary Refractory High-entropy Alloy

    Science.gov (United States)

    Wang, W. L.; Hu, L.; Yang, S. J.; Wang, A.; Wang, L.; Wei, B.

    2016-11-01

    The high-entropy configuration of equiatomic multicomponent alloys opens an effective access to the development of advanced materials. Here we report the synthesis of a new quinary refractory WMoTaNbZr high-entropy alloy under electrostatic levitation condition. It showed a high liquidus temperature of 2686 K and achieved a maximum supercooling of 640 K (0.24 TL) at molten state. The containerless measurements revealed a linear increasing tendency for both its liquid state density and the specific heat to emissivity ratio versus alloy supercooling. A high-entropy body-centered cubic (HEB) phase dominated its phase constitution despite the formation of a negligible amount of solid solution (Zr) phase. The dendritic growth of HEB phase always governed the crystallization process, attained a fastest growth velocity of 13.5 m/s and displayed a power function relation to alloy supercooling. The high speed videographic research of recalescence phenomenon indicated Johnson-Mehl-Avrami type transition kinetics for its rapid solidification process. As supercooling increases, the microstructures of primary HEB phase were refined conspicuously and exhibited an obvious solute trapping effect of the segregative Zr component. Meanwhile, the Vickers hardness of HEB phase displayed the rising tendency with supercooling.

  6. Computational Capabilities for Predictions of Interactions at the Grain Boundary of Refractory Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Sengupta, Debasis; Kwak, Shaun; Vasenkov, Alex; Shin, Yun Kyung; Duin, Adri van

    2014-09-30

    New high performance refractory alloys are critically required for improving efficiency and decreasing CO2 emissions of fossil energy systems. The development of these materials remains slow because it is driven by a trial-and-error experimental approach and lacks a rational design approach. Atomistic Molecular Dynamic (MD) design has the potential to accelerate this development through the prediction of mechanical properties and corrosion resistance of new materials. The success of MD simulations depends critically on the fidelity of interatomic potentials. This project, in collaboration with Penn State, has focused on developing and validating high quality quantum mechanics based reactive potentials, ReaxFF, for Ni-Fe-Al-Cr-O-S system. A larger number of accurate density functional theory (DFT) calculations were performed to generate data for parameterizing the ReaxFF potentials. These potentials were then used in molecular dynamics (MD) and molecular dynamics-Monte Carlo (MD-MC) for much larger system to study for which DFT calculation would be prohibitively expensive, and to understand a number of chemical phenomena Ni-Fe-Al-Cr-O-S based alloy systems . These include catalytic oxidation of butane on clean Cr2O3 and pyrite/Cr2O3, interfacial reaction between Cr2O3 (refractory material) and Al2O3 (slag), cohesive strength of at the grain boundary of S-enriched Cr compared to bulk Cr and Ssegregation study in Al, Al2O3, Cr and Cr2O3 with a grain structure. The developed quantum based ReaxFF potential are available from the authors upon request. During this project, a number of papers were published in peer-reviewed journals. In addition, several conference presentations were made.

  7. Computational Capabilities for Predictions of Interactions at the Grain Boundary of Refractory Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Sengupta, Debasis; Kwak, Shaun; Vasenkov, Alex; Shin, Yun Kyung; Duin, Adri van

    2014-09-30

    New high performance refractory alloys are critically required for improving efficiency and decreasing CO2 emissions of fossil energy systems. The development of these materials remains slow because it is driven by a trial-and-error experimental approach and lacks a rational design approach. Atomistic Molecular Dynamic (MD) design has the potential to accelerate this development through the prediction of mechanical properties and corrosion resistance of new materials. The success of MD simulations depends critically on the fidelity of interatomic potentials. This project, in collaboration with Penn State, has focused on developing and validating high quality quantum mechanics based reactive potentials, ReaxFF, for Ni-Fe-Al-Cr-O-S system. A larger number of accurate density functional theory (DFT) calculations were performed to generate data for parameterizing the ReaxFF potentials. These potentials were then used in molecular dynamics (MD) and molecular dynamics-Monte Carlo (MD-MC) for much larger system to study for which DFT calculation would be prohibitively expensive, and to understand a number of chemical phenomena Ni-Fe-Al-Cr-O-S based alloy systems . These include catalytic oxidation of butane on clean Cr2O3 and pyrite/Cr2O3, interfacial reaction between Cr2O3 (refractory material) and Al2O3 (slag), cohesive strength of at the grain boundary of S-enriched Cr compared to bulk Cr and Ssegregation study in Al, Al2O3, Cr and Cr2O3 with a grain structure. The developed quantum based ReaxFF potential are available from the authors upon request. During this project, a number of papers were published in peer-reviewed journals. In addition, several conference presentations were made.

  8. Computational Capabilities for Predictions of Interactions at the Grain Boundary of Refractory Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Sengupta, Debasis [CFD Research Corporation, Huntsville, AL (United States); Kwak, Shaun [CFD Research Corporation, Huntsville, AL (United States); Vasenkov, Alex [CFD Research Corporation, Huntsville, AL (United States); Shin, Yun Kyung [Pennsylvania State Univ., University Park, PA (United States); Duin, Adri van [Pennsylvania State Univ., University Park, PA (United States)

    2014-12-01

    New high performance refractory alloys are critically required for improving efficiency and decreasing CO2 emissions of fossil energy systems. The development of these materials remains slow because it is driven by a trial-and-error experimental approach and lacks a rational design approach. Atomistic Molecular Dynamic (MD) design has the potential to accelerate this development through the prediction of mechanical properties and corrosion resistance of new materials. The success of MD simulations depends critically on the fidelity of interatomic potentials. This project, in collaboration with Penn State, has focused on developing and validating high quality quantum mechanics based reactive potentials, ReaxFF, for Ni-Fe-Al-Cr-O-S system. A larger number of accurate density functional theory (DFT) calculations were performed to generate data for parameterizing the ReaxFF potentials. These potentials were then used in molecular dynamics (MD) and molecular dynamics-Monte Carlo (MD-MC) for much larger system to study for which DFT calculation would be prohibitively expensive, and to understand a number of chemical phenomena Ni-Fe-Al-Cr-O-S based alloy systems . These include catalytic oxidation of butane on clean Cr2O3 and pyrite/Cr2O3, interfacial reaction between Cr2O3 (refractory material) and Al2O3 (slag), cohesive strength of at the grain boundary of S-enriched Cr compared to bulk Cr and Ssegregation study in Al, Al2O3, Cr and Cr2O3 with a grain structure. The developed quantum based ReaxFF potential are available from the authors upon request. During this project, a number of papers were published in peer-reviewed journals. In addition, several conference presentations were made.

  9. High Temperature Silicides and Refractory Alloys Symposium Held in Boston, Massachusetts on November 29 -December 2, 1993. Volume 322

    Science.gov (United States)

    1993-12-02

    Kinetics, M. Atzmon, J.M.E. Harper, A.L. Greer, M.R. Libera, 1993, ISBN: 1-55899-207-3 Volume 312- Common Themes and Mechanisms of Epitaxial Growth, P...characteristics. Table TH1. Commercial Refractory Metals and Alloys and Associated Melting Processes Base Metal Alloy Additions, wt. % How Made Nb EBM Nb 171... EBM ; EBM +VAM; PHM Nb 7.5Ta EBM +VAM Nb 45-48Ti EBM +VAM; PHM. Nb 44TI-25Ta PHM Nb 55Tt PEIM Ta ERM Ta 2.5W EBM +VAM Ta low EBM +VAM Ta 4ONb EBM + YAM Mo(Low

  10. Synthesis of nanometric refractory alloys powders in the Mo−Nb−W system

    Energy Technology Data Exchange (ETDEWEB)

    Kentheswaran, Vasuki; Dine, Sarah [Université Paris 13, Sorbonne Paris Cité, LSPM, CNRS UPR 3407, 99 avenue Jean-Baptiste Clément, 93430 Villetaneuse (France); Vrel, Dominique, E-mail: dominique.vrel@lspm.cnrs.fr [Université Paris 13, Sorbonne Paris Cité, LSPM, CNRS UPR 3407, 99 avenue Jean-Baptiste Clément, 93430 Villetaneuse (France); Couzinié, Jean-Philippe [ICMPE, Université Paris Est, UMR 7182, CNRS, UPEC, 94320 Thiais (France); Dirras, Guy [Université Paris 13, Sorbonne Paris Cité, LSPM, CNRS UPR 3407, 99 avenue Jean-Baptiste Clément, 93430 Villetaneuse (France)

    2016-09-15

    Nanometric powders of stoichiometric compositions in the Mo−Nb, Mo−W, Nb−W binary systems and in the Mo−Nb−W ternary system were produced by highly exothermic reactions using Mechanically Induced Chemical Reaction (MICR), Self-propagating High-temperature Synthesis (SHS) and Mechanically Activated Self-propagating High-temperature Synthesis (MASHS), through the reduction of their oxides by magnesium, with sodium chloride used as a reaction moderator. Results demonstrate the possibility to obtain high purity nanostructured products in the 20–150 nm range, with an average equivalent diameter, from specific surface measurements, of 44 nm. However, in Nb containing samples, the main BCC phase always comes with one or more secondary phases, for which further developments are necessary in order either to avoid its formation or to find a way to eliminate it. - Highlights: • Nanometric refractory powders in the Mo−Nb−W system have been synthesized. • Three high-energy processes (SHS, MASHS, milling) have been compared. • Process parameters can be adjusted to yield homogeneous alloys in the nanoscale.

  11. Microstructure and Mechanical Properties of a Refractory CoCrMoNbTi High-Entropy Alloy

    Science.gov (United States)

    Zhang, Mina; Zhou, Xianglin; Li, Jinghao

    2017-08-01

    In this work, a new refractory high-entropy alloy, the Co-Cr-Mo-Nb-Ti system, was proposed as a family of candidate materials for high-temperature structural applications. CoCrMoNbTi x ( x values in terms of molar ratios, x = 0, 0.2, 0.4, 0.5 and 1.0) alloys were prepared by vacuum arc melting. The effects of variations in the Ti content on the phase constituents, microstructure and mechanical properties of the alloys were investigated using x-ray diffractometry, scanning electron microscopy equipped with energy-dispersive x-ray spectroscopy and compressive testing. The results showed that the CoCrMoNbTi0.4 alloy possessed a typical cast dendritic microstructure consisting of a single body-centered cubic (BCC) solid solution. Laves phases (Cr2Nb and Co2Ti) were formed in other alloys with different Ti contents. The results were discussed in terms of the mixing enthalpy, atomic size difference, electronegativity difference and valance electron concentrations among the elements within alloys. The alloy hardness exhibited a slightly decreasing trend as the Ti content increased, resulting from the coarser microstructure and reduced amount of Laves phases. Augmented Ti content increased the compressive strength, but decreased the ductility. Particularly, for the CoCrMoNbTi0.2 alloy, the hardness, compressive strength and fracture strain were as high as 916.46 HV0.5, 1906 MPa and 5.07%, respectively. The solid solution strengthening of the BCC matrix and the formation of hard Laves phases were two main factors contributing to alloy strengthening.

  12. Corrosion of refractory alloys induced by sodium sulphate in simulated low oxygen potential atmospheres of the BTL plants

    Energy Technology Data Exchange (ETDEWEB)

    Couture, Ludovic [Grenoble Univ., Saint Martin d' Heres (France). SIMaP; IFP, Solaize (France). Materials Dept.; Galerie, Alain; Wouters, Yves [Grenoble Univ., Saint Martin d' Heres (France). SIMaP; Grosjean, Francois; Kittel, Jean; Ropital, Francois [IFP, Solaize (France). Materials Dept.

    2010-07-01

    BTL (biomass to liquid) is an innovative process to synthesize second generation bio-gasoline from wood and farm residues. In the present work, the effect of sodium sulphate on the high-temperature corrosion at 900 C of two refractory alloys, the chromia-forming Haynes {sup registered} HR-120 and the alumina-forming Haynes {sup registered} 214 in a simulated process atmosphere CO/H{sub 2}/CO{sub 2} (45/45/10% vol.), was investigated for durations up to 96 h. (orig.)

  13. Microstructure and properties of novel quinary multi-principal element alloys with refractory elements

    Directory of Open Access Journals (Sweden)

    Na-na Guo

    2015-09-01

    Full Text Available Five equiatomic alloys (TiZrHfVNb, TiZrHfVTa, TiZrNbMoV, TiZrHfMoV and ZrNbMoHfV composed of five elements with high melting temperature, respectively were prepared by arc-melting to develop a novel high temperature alloy. The five alloys exhibit different dendritic and interdendritic morphologies. The TiZrHfVNb, TiZrHfVTa and TiZrNbMoV alloys formed disordered solid solution phases with body-centered cubic structure, and exhibited high compressive strength and good plasticity. The TiZrHfMoV and ZrNbMoHfV alloys are composed with Laves phase (HfMo2 and disordered solid solution phases with body-centered cubic structure. The TiZrHfMoV and ZrNbMoHfV alloys are harder and more brittle than the other three alloys due to the existence of hard and brittle Laves phases. At high temperatures, the strength decreases to below 300 MPa for the TiZrHfVNb and TiZrHfMoV alloys. Solution strengthening is the primary strengthening mechanism of the TiZrHfVNb, TiZrHfVTa and TiZrNbMoV alloys, and brittle Laves phase is the main cause for the low ductility of the TiZrHfMoV and ZrNbMoHfV alloys.

  14. Mechanical Properties of Refractory High Entropy Alloys Fabricated by Powder Processing

    Energy Technology Data Exchange (ETDEWEB)

    Kuk, Seoung Woo; Kim, Ki Hwan [Korea Atomic Energy Research Institute, Yuseong, Daejeon (Korea, Republic of); Lim, Woo Jin; Kang, Byung Chul; Hong, Soon Hyung; Ryu, Ho Jin [KAIST, Daejeon (Korea, Republic of)

    2015-10-15

    The effects of high configurational entropy, lattice distortion and sluggish diffusion are attributed to the distinguishable behavior of high entropy alloys. The structural applications of high entropy alloys are also promising in advanced nuclear energy systems for nuclear fission and fusion applications. Because of the randomly occupied lattice points by atoms with different atomic radius, lattice distortions and local atomic level strain were developed. The local lattice distortions influence the mechanical properties of high entropy alloys. The strengthening of high entropy alloys is attributed to the lattice distortions and local atomic level strain that increase the resistance to the dislocation motion. Some high entropy alloys exhibit remarkable irradiation resistance. Nagase et al. reported that the Conference alloy was irradiation resistant up to 40 dpa. Ega mi proposed that the irradiation defects can be self-healed because the recrystallization happens more easily in high entropy alloys. The mechanically alloyed and sintered samples have a much smaller grain size than that in cast high entropy alloys.

  15. Low-Density, Refractory Multi-Principal Element Alloys of the Cr-Nb-Ti-V-Zr System: Microstructure and Phase Analysis (Postprint)

    Science.gov (United States)

    2012-12-19

    three disordered bcc phases . The CrNbTiZr and CrNbTiVZr alloys contain a disordered bcc phase and an ordered Laves phase . The lattice parameters and...trends, but are unable to accurately predict vol- ume fractions and compositions of the Laves phases in the CrNbTiZr and CrNbTiVZr alloys. 5. Although the...REFRACTORY MULTI-PRINCIPAL ELEMENT ALLOYS OF THE Cr–Nb–Ti–V–Zr SYSTEM: MICROSTRUCTURE AND PHASE ANALYSIS (POSTPRINT) 5a. CONTRACT NUMBER In-house

  16. 77 FR 59892 - Carbon and Certain Alloy Steel Wire Rod From Mexico: Affirmative Final Determination of...

    Science.gov (United States)

    2012-10-01

    ... International Trade Administration Carbon and Certain Alloy Steel Wire Rod From Mexico: Affirmative Final... mm to 5.0 mm. \\1\\ See Carbon and Certain Alloy Steel Wire Rod from Mexico: Affirmative Preliminary... on said entries.\\4\\ \\2\\ See Carbon and Certain Alloy Steel Wire Rod from Mexico: Initiation of...

  17. Cladding Alloys for Fluoride Salt Compatibility Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Muralidharan, Govindarajan [ORNL; Wilson, Dane F [ORNL; Santella, Michael L [ORNL; Holcomb, David Eugene [ORNL

    2011-05-01

    This interim report provides an overview of several candidate technologies for cladding nickel-based corrosion protection layers onto high-temperature structural alloys. The report also provides a brief overview of the welding and weld performance issues associated with joining nickel-clad nickel-based alloys. From the available techniques, two cladding technologies were selected for initial evaluation. The first technique is a line-of-sight method that would be useful for coating large structures such as vessel interiors or large piping. The line-of-sight method is a laser-based surface cladding technique in which a high-purity nickel powder mixed into a polymer binder is first sprayed onto the surface, baked, and then rapidly melted using a high power laser. The second technique is a vapor phase technique based on the nickel-carbonyl process that is suitable for coating inaccessible surfaces such as the interior surfaces of heat exchangers. The final project report will feature an experimental evaluation of the performance of the two selected cladding techniques.

  18. Effect of Al addition on mechanical properties and microstructure of refractory Al{sub x}HfNbTaTiZr alloys

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Chun-Ming, E-mail: clin112@asu.edu; Juan, Chien-Chang; Chang, Chia-Hsiu; Tsai, Che-Wei; Yeh, Jien-Wei, E-mail: jwyeh@mx.nthu.edu.tw

    2015-03-05

    Highlights: • The study developed a series of refractory Al{sub x}HfNbTaTiZr HEAs. • The aim to improve strength, and reduce density of the very ductile base alloy. • These HEAs mainly consist of a simple BCC solid solution. • The addition of Al significantly improved the strength characteristics. • Solution hardening led to a decrease in ductility. - Abstract: This study developed a series of refractory Al{sub x}HfNbTaTiZr high-entropy alloys (HEAs) with an aim to improve strength, and reduce density of the very ductile base alloy HfNbTaTiZr. Despite the diversity of crystal structures among the constituent elements, all the HEAs are single solid solution phase with body-centered cubic (BCC) structure. The addition of Al significantly improves the strength but reduces the ductility due to large solution hardening. The linear relation between yield strength and atomic percentage of Al suggests that the strengthening effect of a certain element in a single-phase HEA alloy can be explained based on quasi-binary alloy concept. Crack formations in deformed AlHfNbTaTiZr alloy with the lowest fracture strain are mainly along the boundaries between dendrite and interdendrite. This agrees with its large deviation of Al content and thus strength between dendrite and interdendrite.

  19. Refractory experience in circulating fluidized bed combustors, Task 7. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Vincent, R.Q.

    1989-11-01

    This report describes the results of an investigation into the status of the design and selection of refractory materials for coal-fueled circulating fluidized-bed combustors. The survey concentrated on operating units in the United States manufactured by six different boiler vendors: Babcock and Wilcox, Combustion Engineering, Foster Wheeler, Keeler Dorr-Oliver, Pyropower, and Riley Stoker. Information was obtained from the boiler vendors, refractory suppliers and installers, and the owners/operators of over forty units. This work is in support of DOE`s Clean Coal Technology program, which includes circulating fluidized-bed technology as one of the selected concepts being evaluated.

  20. Mechanical Properties of Nb25Mo25Ta25W25 and V20Nb20Mo20Ta20W20 Refractory High Entropy Alloys (Postprint)

    Science.gov (United States)

    2011-05-01

    temper ature from 548 MPa at 1000 C to 405 MPa at 1600 C (Table 2).ublic release; distribution unlimited. Table 4 Composition (in wt.%) of Inconel 718 ...values of the refractory HEAs are much higher than those of Haynes 230 at all studied temperatures and higher than those of Inconel 718 at...than twice (for the Nb25Mo25 Ta25W25 alloy) or four times (for the V20Nb20Mo20Ta20W20 alloy) higher than for Inconel 718 or Haynes 230 at 1000 C. The

  1. Microstructure Evolution in a New Refractory High-Entropy Alloy W-Mo-Cr-Ti-Al

    Science.gov (United States)

    Gorr, Bronislava; Azim, Maria; Christ, Hans-Juergen; Chen, Hans; Szabo, Dorothee Vinga; Kauffmann, Alexander; Heilmaier, Martin

    2016-02-01

    The microstructure of a body-centered cubic 20W-20Mo-20Cr-20Ti-20Al alloy in the as-cast condition as well as its microstructural evolution during heat treatment was investigated. Different characterization techniques, such as focused ion beam-scanning electron microscope, X-ray diffraction, and transmission electron microscope, were applied. Experimental observations were supported by thermodynamic calculations. The alloy exhibits a pronounced dendritic microstructure in the as-cast condition with the respective dendritic and interdendritic regions showing significant fluctuations of the element concentrations. Using thermodynamic calculations, it was possible to rationalize the measured element distribution in the dendritic and the interdendritic regions. Observations of the microstructure evolution reveal that during heat treatment, substantial homogenization takes place leading to the formation of a single-phase microstructure. Driving forces for the microstructural evolution were discussed from a thermodynamic point of view.

  2. Senary Refractory High-Entropy Alloy HfNbTaTiVZr

    Science.gov (United States)

    Gao, M. C.; Zhang, B.; Yang, S.; Guo, S. M.

    2016-07-01

    Discovery of new single-phase high-entropy alloys (HEAs) is important to understand HEA formation mechanisms. The present study reports computational design and experimental validation of a senary HEA, HfNbTaTiVZr, in a body-centered cubic structure. The phase diagrams and thermodynamic properties of this senary system were modeled using the CALPHAD method. Its atomic structure and diffusion constants were studied using ab initio molecular dynamics simulations. The microstructure of the as-cast HfNbTaTiVZr alloy was studied using X-ray diffraction and scanning electron microscopy, and the microsegregation in the as-cast state was found to qualitatively agree with the solidification predictions from CALPHAD. Supported by both simulation and experimental results, the HEA formation rules are discussed.

  3. 76 FR 45509 - Final Results of Antidumping Duty Changed Circumstances Review: Carbon and Certain Alloy Steel...

    Science.gov (United States)

    2011-07-29

    ... Circumstances Review: Carbon and Certain Alloy Steel Wire Rod from Mexico, 75 FR 67685 (November 3, 2010...: Carbon and Certain Alloy Steel Wire Rod From Mexico, 71 FR 27989 (May 15, 2006). Notification This notice... International Trade Administration Final Results of Antidumping Duty Changed Circumstances Review: Carbon...

  4. De-alloying and stress-corrosion cracking. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Sieradzki, K.

    1998-09-01

    This research program has had two major areas of focus that are related: (1) alloy corrosion and (2) the role of selective dissolution in the stress corrosion cracking of alloy systems. These interrelated issues were examined using model systems such as Ag-Au and Cu-Au by conventional electrochemical techniques, in situ scanning tunneling microscopy (STM), in situ small angle neutron scattering (SANS), ultrahigh speed digital photography of fracture events, and computer simulations. The STM and SANS work were specifically aimed at addressing a roughening transition known to occur in alloy systems undergoing corrosion at electrochemical potentials greater than the so-called critical potential. Analytical models of de-alloying processes including the roughening transition were developed that specifically include curvature effects that are important in alloy corrosion processes. Stress-corrosion experiments were performed on the same model systems using rapid optical and electrochemical techniques on 50 {micro}m--250 {micro}m thick sheets and small diameter wires. The primary goal of this work was to develop a fundamental understanding of the corrosion and electrochemistry of alloys and the stress-corrosion cracking processes these alloys undergo. Computer simulations and analytical work identified surface stress and an important parameter in environmentally assisted fracture. The major results of the research on this program since the summer of 1993 are briefly summarized.

  5. COST 507: Thermophysical properties of light metal alloys. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Jaroma-Weiland, G.; Brandt, R.; Neuer, G.

    1994-02-15

    The thermophysical properties of Al-, Mg- and Ti-based light metal alloys have been studied by reviewing the literature published so far, evaluating the empirical results and by empirical investigations. The properties to the covered in the literature research are: thermal conductivity, thermal diffusivity, specific heat capacity, thermal expansion and electrical resistivity. The data have been stored in the factual data base THERSYST together with the results of experimental measurements supplied from participants of the COST 507-action (Group D). Altogether 1325 data-sets referring to 146 alloys have been stored. They have been uniformly represented and critically analyzed by means of the THERSYST program moduli. These numerical data cover a number of systems with variing chemical composition and thermal treatment. Partly large discrepancies especially of the thermal conductivity have been found for similar alloys. The problem of experimental uncertainities has been studied in detail by investigation of AA-8090 alloy (Al-2.5Li-1.1Cu). The thermophysical properties of monolithic alloy KS1275 (AlSi12CuNi) and metal matrix composite (KS1275 reinforced with Al2O3 short fibre) have been determined experimentally. (orig.)

  6. Intermetallic alloys: patterns and complexity. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborty, Bulbul

    2001-11-07

    This report summarizes the research accomplishment of the P.I. and her collaborators. The major findings are (a) in the area of ordering in metallic alloys, the interplay between chemical and structural short-range order and (b) in the area of glassy dynamics in frustrated spin models. In the context of alloys, the development of a theoretical framework for incorporating the correlation between chemical and structural degrees of freedom has been a major accomplishment. The work on frustrated spin models has had a major impact on the understanding of the glass transition.

  7. Design, engineering and evaluation of refractory liners for slagging gasifiers. Final report

    Energy Technology Data Exchange (ETDEWEB)

    deTineo, B J; Booth, G; Firestone, R F; Greaves, M J; Hales, C; Lamoureux, J P; Ledford, R R

    1982-08-01

    The contract for this program was awarded at the end of September 1978. Work was started on 1 October 1978, on Tasks A, B, and E. Task A, Conceptual Liner Designs, and Task B, Test System Design and Construction, were completed. Task C, Liner Tests, and Task D, Liner Design Evaluation, were to begin upon completion of Task B. Task E, Liner Model Development, is inactive after an initial data compilation and theoretical model development effort. It was to be activated as soon as data were available from Task D. Task F, Liner Design Handbook, was active along with Task A since the reports of both tasks were to use the same format. At this time, Tasks C, D, and F are not to be completed since funding of this project was phased out by DOE directive. The refractory text facility, which was constructed, was tested and found to perform satisfactorily. It is described in detail, including a hazard analysis which was performed. (LTN)

  8. Design, engineering and evaluation of refractory liners for slagging gasifiers. Final report

    Energy Technology Data Exchange (ETDEWEB)

    deTineo, B J; Booth, G; Firestone, R F; Greaves, M J; Hales, C; Lamoureux, J P; Ledford, R R

    1982-08-01

    The contract for this program was awarded at the end of September 1978. Work was started on 1 October 1978, on Tasks A, B, and E. Task A, Conceptual Liner Designs, and Task B, Test System Design and Construction, were completed. Task C, Liner Tests, and Task D, Liner Design Evaluation, were to begin upon completion of Task B. Task E, Liner Model Development, is inactive after an initial data compilation and theoretical model development effort. It was to be activated as soon as data were available from Task D. Task F, Liner Design Handbook, was active along with Task A since the reports of both tasks were to use the same format. At this time, Tasks C, D, and F are not to be completed since funding of this project was phased out by DOE directive. The refractory text facility, which was constructed, was tested and found to perform satisfactorily. It is described in detail, including a hazard analysis which was performed. (LTN)

  9. Development of Ion-Plasma Coatings for Protecting Intermetallic Refractory Alloys VKNA-1V and VKNA-25 in the Temperature Range of 1200 - 1250°C

    Science.gov (United States)

    Budinovskii, S. A.; Matveev, P. V.; Smirnov, A. A.

    2017-05-01

    Multilayer heat-resistant ion-plasma coatings for protecting the parts of the hot duct of gas-turbine engines produced from refractory nickel alloys based on VKNA intermetallics from high-temperature oxidation are considered. Coatings of the Ni - Cr - Al (Ta, Re, Hf, Y) + Al - Ni - Y systems are tested for high-temperature strength at 1200 and 1250°C. Metallographic and microscopic x-ray spectrum analyses of the structure and composition of the coatings in the initial condition and after the testing are performed. The effect of protective coatings of the Ni - Cr - Al - Hf + Al - Ni - Y systems on the long-term strength of alloys VKNA-1V and VKNA-25 at 1200°C is studied.

  10. Material development for waste-to-energy plants. Refractory linings. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hede Larsen, O.

    2010-10-15

    stress levels between steel and refractory with the higher stress level at the top of the panel wall tube. As, however, no intimate and solid bond exists in the finite border layer between the two, the expected cracking may not occur. At least it has not been observed in reality. Experiments with forced, vigorous heating of dried and wet castable blocks, respectively, confirm that spalling and cracking at initial lining heat-up are caused by reversible thermal expansion below boiling point of free, unbonded water left in the micro and capillary porosity, and not by decomposition of hydrates. (Author)

  11. Impact of the De-Alloying Kinetics and Alloy Microstructure on the Final Morphology of De-Alloyed Meso-Porous Metal Films

    Directory of Open Access Journals (Sweden)

    Bao Lin

    2014-10-01

    Full Text Available Nano-textured porous metal materials present unique surface properties due to their enhanced surface energy with potential applications in sensing, molecular separation and catalysis. In this paper, commercial alloy foils, including brass (Cu85Zn15 and Cu70Zn30 and white gold (Au50Ag50 foils have been chemically de-alloyed to form nano-porous thin films. The impact of the initial alloy micro-structure and number of phases, as well as chemical de-alloying (DA parameters, including etchant concentration, time and solution temperature on the final nano-porous thin film morphology and properties were investigated by electron microscopy (EM. Furthermore, the penetration depth of the pores across the alloys were evaluated through the preparation of cross sections by focus ion beam (FIB milling. It is demonstrated that ordered pores ranging between 100 nm and 600 nm in diameter and 2–5 μm in depth can be successfully formed for the range of materials tested. The microstructure of the foils were obtained by electron back-scattered diffraction (EBSD and linked to development of pits across the material thickness and surface during DA. The role of selective etching of both noble and sacrificial metal phases of the alloy were discussed in light of the competitive surface etching across the range of microstructures and materials tested.

  12. Development of high performance refractory fibers with enhanced insulating properties and longer service lifetimes: Phase 2, Improved refractory fiber and industrial benefit development. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Yifang; Curtis, J.M.; DePoorter, G.L.; Martin, P.C.; Munoz, D.R. [Colorado School of Mines, Golden, CO (United States). Dept. of Metallurgical and Materials Engineering

    1995-05-01

    This is Phase II of a three-phase study for the development of high performance refractory fibers with enhanced insulating properties and longer service lifetimes, for use in the aluminum, glass, cement, and iron and steel industries. Fiberization of 24 out of 25 compositions in the Al{sub 2}O{sub 3}-Si0{sub 2}-Zr0{sub 2} system were achieved. These 24 and three existing fiber compositions were evaluated: The shrinkage and the crystalline and vitreous phases were determined vs heat treatment time and temperature. Four theoretical models were developed: Shrinkage, devitrification kinetics, density change, and fiberization. Although some of the fibers formed during Phase II had properties as good as the reference ASZ fiber, no fiber had a significantly improved performance. This work, although not entirely successful, did produce significant benefits to refractory insulating fiber manufacturers and users: Mechanisms of both linear and thickness shrinkage for vitreous refractory fibers were determined, devitrification kinetics were quantified and used in models to predict shrinkage during service, and the mechanism of fiber formation in the melt spinning process was studied.

  13. 78 FR 60850 - Carbon and Certain Alloy Steel Wire Rod From Brazil: Final Results of the Expedited Second Sunset...

    Science.gov (United States)

    2013-10-02

    ... International Trade Administration Carbon and Certain Alloy Steel Wire Rod From Brazil: Final Results of the... certain alloy steel wire rod (wire rod) from Brazil would be likely to lead to continuation or recurrence... Alloy Steel Wire Rod from Brazil, 67 FR 55805 (August 30, 2002). \\2\\ See Initiation of...

  14. 76 FR 36089 - Circular Welded Non-Alloy Steel Pipe From the Republic of Korea: Final Results of the Antidumping...

    Science.gov (United States)

    2011-06-21

    ... International Trade Administration Circular Welded Non-Alloy Steel Pipe From the Republic of Korea: Final... circular welded non-alloy steel pipe (``CWP'') from the Republic of Korea (``Korea''), covering the period.... SUPPLEMENTARY INFORMATION: Background Following publication of Circular Welded Non-Alloy Steel Pipe From...

  15. 77 FR 34344 - Circular Welded Non-Alloy Steel Pipe From the Republic of Korea: Final Results of the Antidumping...

    Science.gov (United States)

    2012-06-11

    ... International Trade Administration Circular Welded Non-Alloy Steel Pipe From the Republic of Korea: Final... circular welded non-alloy steel pipe (``CWP'') from the Republic of Korea (``Korea''). The review covers...: Background Following Circular Welded Non-Alloy Steel Pipe From the Republic of Korea: Preliminary Results...

  16. 78 FR 35248 - Circular Welded Non-Alloy Steel Pipe From the Republic of Korea: Final Results of Antidumping...

    Science.gov (United States)

    2013-06-12

    ... International Trade Administration Circular Welded Non-Alloy Steel Pipe From the Republic of Korea: Final... order on circular welded non-alloy steel pipe (CWP) from the Republic of Korea (Korea) for the period... has been sold at less than normal value. \\1\\ See Circular Welded Non-Alloy Steel Pipe From...

  17. 78 FR 34342 - Certain Circular Welded Non-Alloy Steel Pipe From Mexico: Final Results and Partial Rescission of...

    Science.gov (United States)

    2013-06-07

    ... International Trade Administration Certain Circular Welded Non-Alloy Steel Pipe From Mexico: Final Results and... duty order on certain circular welded non- alloy steel pipe from Mexico.\\1\\ This administrative review.... \\1\\ See Certain Circular Welded Non-Alloy Steel Pipe From Mexico: Preliminary Results and...

  18. 78 FR 28190 - Carbon and Certain Alloy Steel Wire Rod From Mexico: Final Results of Antidumping Duty...

    Science.gov (United States)

    2013-05-14

    ... International Trade Administration Carbon and Certain Alloy Steel Wire Rod From Mexico: Final Results of... carbon and certain alloy steel wire rod (wire rod) from Mexico. The period of review (POR) is October 1... (the Act). \\1\\ See Carbon and Certain Alloy Steel Wire Rod From Mexico: Preliminary Results...

  19. 77 FR 13545 - Carbon and Certain Alloy Steel Wire Rod From Mexico: Notice of Final Results of Antidumping Duty...

    Science.gov (United States)

    2012-03-07

    ... International Trade Administration Carbon and Certain Alloy Steel Wire Rod From Mexico: Notice of Final Results... duty order on carbon and certain alloy steel wire rod (wire rod) from Mexico.\\1\\ This review covers.... \\1\\ See Carbon and Certain Alloy Steel Wire Rod from Mexico: Notice of Preliminary Results...

  20. Interaction mechanism between niobium-silicide-based alloy melt and Y2O3 refractory crucible in vacuum induction melting process

    Directory of Open Access Journals (Sweden)

    Gao Ming

    2011-05-01

    Full Text Available The Y2O3 crucibles were introduced in the study as an alternative to the traditional ceramic ones in vacuum induction melting of multi-component Nb-16Si-22Ti-2Al-2Hf-17Cr (at.% alloys, to reveal the possible interactions between the alloy melt and the refractory crucible. Multiple melting time lengths and two cooling schemes were designed and used for the experiments. The chemical composition and microstructure of the tested alloy and the melt-crucible interaction were investigated and evaluated. In the experiments, Y2O3 crucible displays good physical-chemical compatibility. The results indicate that the increment of O element in the as-cast ingot is 0.03at.%-0.04at.% (72-97 ppm and the increment of Y element is very insignificant. The key features of the alloy melt interacting with Y2O3 ceramics are analyzed and concluded in the paper. As a result of the dissolution reaction xY2O3 (in molten alloy + (1-xHfO2 (impurity →Hf1-xY2xO2-x, a continuous double-layer solid film consisted of HfO2 solid solution (~2 μm and pure HfO2 (~5 μm is formed on the surface of the test ingot after cooled down in the crucible. The experimental results show that the Y2O3 crucible is applicable to the vacuum induction melting of Nb-Si based alloys.

  1. Theoretical Model for Volume Fraction of UC, 235U Enrichment, and Effective Density of Final U 10Mo Alloy

    Energy Technology Data Exchange (ETDEWEB)

    Devaraj, Arun [Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Environmental Molecular Sciences Lab. (EMSL); Prabhakaran, Ramprashad [Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Environmental Molecular Sciences Lab. (EMSL); Joshi, Vineet V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Environmental Molecular Sciences Lab. (EMSL); Hu, Shenyang Y. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Environmental Molecular Sciences Lab. (EMSL); McGarrah, Eric J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Environmental Molecular Sciences Lab. (EMSL); Lavender, Curt A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Environmental Molecular Sciences Lab. (EMSL)

    2016-04-12

    The purpose of this document is to provide a theoretical framework for (1) estimating uranium carbide (UC) volume fraction in a final alloy of uranium with 10 weight percent molybdenum (U 10Mo) as a function of final alloy carbon concentration, and (2) estimating effective 235U enrichment in the U 10Mo matrix after accounting for loss of 235U in forming UC. This report will also serve as a theoretical baseline for effective density of as-cast low-enriched U 10Mo alloy. Therefore, this report will serve as the baseline for quality control of final alloy carbon content

  2. Chemical Frustration. A Design Principle for the Discovery of New Complex Alloy and Intermetallic Phases, Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Fredrickson, Daniel C [Univ. of Wisconsin, Madison, WI (United States)

    2015-06-23

    Final technical report for "Chemical Frustration: A Design Principle for the Discovery of New Complex Alloy and Intermetallic Phases" funded by the Office of Science through the Materials Chemistry Program of the Office of Basic Energy Sciences.

  3. Special Features of Creep and Long-Term Strength of Single-Crystal Refractory Nickel-Base Alloys

    Science.gov (United States)

    Semenov, S. G.; Getsov, L. B.; Tikhomirova, E. A.; Semenov, A. S.

    2016-03-01

    Results of experimental studies of creep in a wide range of temperatures and stresses are presented for three modern single-crystal nickel-base alloys. A method for determining the creep characteristics by tests including step increase of the tension is suggested and tested. The effect of transition into plastic condition on the creep parameters, the influence of the chemical composition and loading conditions on the duration of creep stages I, II and III, and the conditions of appearance of crystallographic and not crystallographic modes of fracture are analyzed. Possible simple approximations of the creep curves are considered with allowance for the accumulation of damage and occurrence of unsteady creep stages.

  4. 高纯难熔金属及其合金单晶的发展%Development of Single Crystals of High-Purity Refractory Metals and Alloys

    Institute of Scientific and Technical Information of China (English)

    李来平; 胡忠武; 殷涛; 张文; 高选乔; 郭林江; 任广鹏; 张平祥; 李中奎

    2014-01-01

    In this paper,we report the processing technology of single crystals of high-purity refractory metals and alloys, and compare the electron-beam floating zone melting(EBFZM)with the plasma arc melting(PAM).By EBFZM,the tem-perature gradient could be controlled easily and the contamination by crucible materials is avoided,whereas the surface tension of melt is sensitive to the active impurity content and the temperature gradient.Furthermore,the dimensions of high-purity refractory metals and the monocrystalline materials are severely limited and the dislocation density in the mate-rials is relatively high.PAM has the advantages such as high energy density of heating and various specifications of raw materials,by which the single crystal castings could be processed in the shape of rod,plate,tube and other specific shapes.Meanwhile,the impurity elements (especially carbon)are maximally removed.However,the equipment is com-plex and the dislocation density is high.We also discuss the status of development for single crystal materials,such as im-proving the resistance to high temperature and stablilty by solid-solution strengthening.The processing of single crystal tubes is also an interesting topic.We make some suggestions on the processing technology and developing prospect for sin-gle crystals of refractory metals and alloys.%介绍了难熔金属及其合金单晶的制备技术,对电子束悬浮区域熔炼技术和等离子弧熔炼技术进行了比较。电子束悬浮区域熔炼法温度梯度易于控制、材料不受坩埚材料污染,但熔体表面张力对活性杂质和温度梯度敏感性高,所能制备的高纯难熔金属及其单晶材料尺寸规格受到很大限制,且材料内部位错密度较高。等离子弧熔炼法加热源能量密度高,原料规格形式多样,可制备单晶棒材、板材、管材及其他特定形状的单晶铸件,可最大程度地去除杂质元素(尤其是C元素),但设备系统复杂,

  5. Obinutuzumab (GA101) in relapsed/refractory chronic lymphocytic leukemia: final data from the phase 1/2 GAUGUIN study.

    Science.gov (United States)

    Cartron, Guillaume; de Guibert, Sophie; Dilhuydy, Marie-Sarah; Morschhauser, Franck; Leblond, Veronique; Dupuis, Jehan; Mahe, Beatrice; Bouabdallah, Reda; Lei, Guiyuan; Wenger, Michael; Wassner-Fritsch, Elisabeth; Hallek, Michael

    2014-10-02

    GAUGUIN evaluated the safety and efficacy of obinutuzumab (GA101) monotherapy in patients with relapsed/refractory chronic lymphocytic leukemia (CLL). In phase 1 (dose escalation), 13 patients received obinutuzumab 400 to 1200 mg (days 1 and 8 of cycle 1; day 1 of cycles 2-8). In phase 2, 20 patients received a fixed dose of 1000 mg (days 1, 8, and 15 of cycle 1; day 1 of cycles 2-8). Infusion-related reactions occurred in nearly all patients, but few were grade 3/4. Grade 3/4 neutropenia occurred in 7 patients in phase 1 (but was not dose-related) and in 4 patients in phase 2. Overall end-of-treatment response (all partial responses) was 62% (phase 1) and 15% (phase 2); best overall response was 62% and 30%, respectively. Phase 2 median progression-free survival was 10.7 months and median duration of response was 8.9 months. In summary, obinutuzumab monotherapy is active in patients with heavily pretreated relapsed/refractory CLL.

  6. Development of models and online diagnostic monitors of the high-temperature corrosion of refractories in oxy/fuel glass furnaces : final project report.

    Energy Technology Data Exchange (ETDEWEB)

    Griffiths, Stewart K.; Gupta, Amul (Monofrax Inc., Falconer, NY); Walsh, Peter M.; Rice, Steven F.; Velez, Mariano (University of Missouri, Rolla, MO); Allendorf, Mark D.; Pecoraro, George A. (PPG Industries, Inc., Pittsburgh, PA); Nilson, Robert H.; Wolfe, H. Edward (ANH Refractories, Pittsburgh, PA); Yang, Nancy Y. C.; Bugeat, Benjamin () American Air Liquide, Countryside, IL); Spear, Karl E. (Pennsylvania State University, University Park, PA); Marin, Ovidiu () American Air Liquide, Countryside, IL); Ghani, M. Usman (American Air Liquide, Countryside, IL)

    2005-02-01

    This report summarizes the results of a five-year effort to understand the mechanisms and develop models that predict the corrosion of refractories in oxygen-fuel glass-melting furnaces. Thermodynamic data for the Si-O-(Na or K) and Al-O-(Na or K) systems are reported, allowing equilibrium calculations to be performed to evaluate corrosion of silica- and alumina-based refractories under typical furnace operating conditions. A detailed analysis of processes contributing to corrosion is also presented. Using this analysis, a model of the corrosion process was developed and used to predict corrosion rates in an actual industrial glass furnace. The rate-limiting process is most likely the transport of NaOH(gas) through the mass-transport boundary layer from the furnace atmosphere to the crown surface. Corrosion rates predicted on this basis are in better agreement with observation than those produced by any other mechanism, although the absolute values are highly sensitive to the crown temperature and the NaOH(gas) concentration at equilibrium and at the edge of the boundary layer. Finally, the project explored the development of excimer laser induced fragmentation (ELIF) fluorescence spectroscopy for the detection of gas-phase alkali hydroxides (e.g., NaOH) that are predicted to be the key species causing accelerated corrosion in these furnaces. The development of ELIF and the construction of field-portable instrumentation for glass furnace applications are reported and the method is shown to be effective in industrial settings.

  7. Powder Metallurgy of Uranium Alloy Fuels for TRU-Burning Reactors Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    McDeavitt, Sean M

    2011-04-29

    Overview Fast reactors were evaluated to enable the transmutation of transuranic isotopes generated by nuclear energy systems. The motivation for this was that TRU isotopes have high radiotoxicity and relatively long half-lives, making them unattractive for disposal in a long-term geologic repository. Fast reactors provide an efficient means to utilize the energy content of the TRUs while destroying them. An enabling technology that requires research and development is the fabrication metallic fuel containing TRU isotopes using powder metallurgy methods. This project focused upon developing a powder metallurgical fabrication method to produce U-Zr-transuranic (TRU) alloys at relatively low processing temperatures (500ºC to 600ºC) using either hot extrusion or alpha-phase sintering for charecterization. Researchers quantified the fundamental aspects of both processing methods using surrogate metals to simulate the TRU elements. The process produced novel solutions to some of the issues relating to metallic fuels, such as fuel-cladding chemical interactions, fuel swelling, volatility losses during casting, and casting mold material losses. Workscope There were two primary tasks associated with this project: 1. Hot working fabrication using mechanical alloying and extrusion • Design, fabricate, and assemble extrusion equipment • Extrusion database on DU metal • Extrusion database on U-10Zr alloys • Extrusion database on U-20xx-10Zr alloys • Evaluation and testing of tube sheath metals 2. Low-temperature sintering of U alloys • Design, fabricate, and assemble equipment • Sintering database on DU metal • Sintering database on U-10Zr alloys • Liquid assisted phase sintering on U-20xx-10Zr alloys Appendices Outline Appendix A contains a Fuel Cycle Research & Development (FCR&D) poster and contact presentation where TAMU made primary contributions. Appendix B contains MSNE theses and final defense presentations by David Garnetti and Grant Helmreich

  8. Powder Metallurgy of Uranium Alloy Fuels for TRU-Burning Reactors Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    McDeavitt, Sean M

    2011-04-29

    Overview Fast reactors were evaluated to enable the transmutation of transuranic isotopes generated by nuclear energy systems. The motivation for this was that TRU isotopes have high radiotoxicity and relatively long half-lives, making them unattractive for disposal in a long-term geologic repository. Fast reactors provide an efficient means to utilize the energy content of the TRUs while destroying them. An enabling technology that requires research and development is the fabrication metallic fuel containing TRU isotopes using powder metallurgy methods. This project focused upon developing a powder metallurgical fabrication method to produce U-Zr-transuranic (TRU) alloys at relatively low processing temperatures (500ºC to 600ºC) using either hot extrusion or alpha-phase sintering for charecterization. Researchers quantified the fundamental aspects of both processing methods using surrogate metals to simulate the TRU elements. The process produced novel solutions to some of the issues relating to metallic fuels, such as fuel-cladding chemical interactions, fuel swelling, volatility losses during casting, and casting mold material losses. Workscope There were two primary tasks associated with this project: 1. Hot working fabrication using mechanical alloying and extrusion • Design, fabricate, and assemble extrusion equipment • Extrusion database on DU metal • Extrusion database on U-10Zr alloys • Extrusion database on U-20xx-10Zr alloys • Evaluation and testing of tube sheath metals 2. Low-temperature sintering of U alloys • Design, fabricate, and assemble equipment • Sintering database on DU metal • Sintering database on U-10Zr alloys • Liquid assisted phase sintering on U-20xx-10Zr alloys Appendices Outline Appendix A contains a Fuel Cycle Research & Development (FCR&D) poster and contact presentation where TAMU made primary contributions. Appendix B contains MSNE theses and final defense presentations by David Garnetti and Grant Helmreich

  9. Refractory vasculitis

    NARCIS (Netherlands)

    Rutgers, Bram; Kallenberg, Cees G. M.

    2011-01-01

    Refractory vasculitis occurs in 4-5% of patients with anti-neutrophil cytoplasmic antibody associated vasculitis (AAV). Differences between therapies used for refractory disease are mostly reflected in the percentages of complete and partial remissions, but also in the number of serious side effects

  10. Refractory vasculitis

    NARCIS (Netherlands)

    Rutgers, Bram; Kallenberg, Cees G. M.

    Refractory vasculitis occurs in 4-5% of patients with anti-neutrophil cytoplasmic antibody associated vasculitis (AAV). Differences between therapies used for refractory disease are mostly reflected in the percentages of complete and partial remissions, but also in the number of serious side

  11. Influence of thermal debinding on the final properties of Fe–Si soft magnetic alloys for metal injection molding (MIM)

    Energy Technology Data Exchange (ETDEWEB)

    Páez-Pavón, A.; Jiménez-Morales, A. [Dpto. Ciencia e Ing. de materiales e Ing. Química, Universidad Carlos III de Madrid, 28911 Leganés, Madrid (Spain); Santos, T.G. [UNIDEMI, Departamento de Engenharia Mecânica e Industrial, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Quintino, L. [Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa (Portugal); Torralba, J.M. [Dpto. Ciencia e Ing. de materiales e Ing. Química, Universidad Carlos III de Madrid, 28911 Leganés, Madrid (Spain)

    2016-10-15

    Metal injection molding (MIM) may be used to produce soft magnetic materials with optimal mechanical and magnetic properties. Unlike other techniques, MIM enables the production of complex and small Fe–Si alloy parts with silicon contents greater than 3% by weight. In MIM process development, it is critical to design a proper debinding cycle not only to ensure complete removal of the binder system but also to obtain improved properties in the final part. This work is a preliminary study on the production of Fe-3.8Si soft magnetic parts by MIM using pre-alloyed powders and a non-industrialized binder. Two different heating rates during thermal debinding were used to study their effect on the final properties of the part. The final properties of the sintered parts are related to thermal debinding. It has been demonstrated that the heating rate during thermal debinding has a strong influence on the final properties of Fe–Si soft magnetic alloys. - Highlights: • The properties of MIM Fe-Si alloy are influenced by the debinding heating rate. • The slow debinding led to a lower porosity, lower oxygen content and grain growth. • The magnetization of the sintered samples improved after a slow thermal debinding.

  12. Influence of Nickel Particle Reinforcement on Cyclic Fatigue and Final Fracture Behavior of a Magnesium Alloy Composite

    Directory of Open Access Journals (Sweden)

    Manoj Gupta

    2012-06-01

    Full Text Available The microstructure, tensile properties, cyclic stress amplitude fatigue response and final fracture behavior of a magnesium alloy, denoted as AZ31, discontinuously reinforced with nano-particulates of aluminum oxide and micron size nickel particles is presented and discussed. The tensile properties, high cycle fatigue and final fracture behavior of the discontinuously reinforced magnesium alloy are compared with the unreinforced counterpart (AZ31. The elastic modulus and yield strength of the dual particle reinforced magnesium alloy is marginally higher than of the unreinforced counterpart. However, the tensile strength of the composite is lower than the monolithic counterpart. The ductility quantified by elongation to failure over 0.5 inch (12.7 mm gage length of the test specimen showed minimal difference while the reduction in specimen cross-section area of the composite is higher than that of the monolithic counterpart. At the microscopic level, cyclic fatigue fractures of both the composite and the monolithic alloy clearly revealed features indicative of the occurrence of locally ductile and brittle mechanisms. Over the range of maximum stress and at two different load ratios the cyclic fatigue resistance of the magnesium alloy composite is superior to the monolithic counterpart. The mechanisms responsible for improved cyclic fatigue life and resultant fracture behavior of the composite microstructure are highlighted.

  13. Process simulation and modeling for advanced intermetallic alloys. Final report, 1 September 1989-31 August 1993

    Energy Technology Data Exchange (ETDEWEB)

    Rack, H.J.

    1994-06-01

    This Final Report summarizes the technical effort for contract 'Process Simulation and Modeling for Advanced Intermetallic Alloys' undertaken under N0001489-J-3166 (RT Project Number: DU 89005) at Clemson University with H. J. Rack, Professor of Mechanical Engineering and Metallurgy acting as Principal Investigator. The report contains two major parts, Phase Stability (Part 1) and High Temperature Deformation Processing (Part 2). Part 1 contains nine (9) papers describing the high temperature phase stability of Ti-Al-Nb and Ti-Al-V intermetallic alloys, primary attention being focused on the temperature regimes normally associated with deformation processing. Part 2 contains three (3) papers which demonstrate the utility of combining phase equilibria studies with Dynamic Material Modeling to simulate and model the high temperature deformation processing response of alpha + beta and alpha 2 + beta titanium alloys.

  14. Influence of thermal debinding on the final properties of Fe-Si soft magnetic alloys for metal injection molding (MIM)

    Science.gov (United States)

    Páez-Pavón, A.; Jiménez-Morales, A.; Santos, T. G.; Quintino, L.; Torralba, J. M.

    2016-10-01

    Metal injection molding (MIM) may be used to produce soft magnetic materials with optimal mechanical and magnetic properties. Unlike other techniques, MIM enables the production of complex and small Fe-Si alloy parts with silicon contents greater than 3% by weight. In MIM process development, it is critical to design a proper debinding cycle not only to ensure complete removal of the binder system but also to obtain improved properties in the final part. This work is a preliminary study on the production of Fe-3.8Si soft magnetic parts by MIM using pre-alloyed powders and a non-industrialized binder. Two different heating rates during thermal debinding were used to study their effect on the final properties of the part. The final properties of the sintered parts are related to thermal debinding. It has been demonstrated that the heating rate during thermal debinding has a strong influence on the final properties of Fe-Si soft magnetic alloys.

  15. The evaluation of the use of metal alloy fuels in pressurized water reactors. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Lancaster, D.

    1992-10-26

    The use of metal alloy fuels in a PWR was investigated. It was found that it would be feasible and competitive to design PWRs with metal alloy fuels but that there seemed to be no significant benefits. The new technology would carry with it added economic uncertainty and since no large benefits were found it was determined that metal alloy fuels are not recommended. Initially, a benefit was found for metal alloy fuels but when the oxide core was equally optimized the benefit faded. On review of the optimization of the current generation of ``advanced reactors,`` it became clear that reactor design optimization has been under emphasized. Current ``advanced reactors`` are severely constrained. The AP-600 required the use of a fuel design from the 1970`s. In order to find the best metal alloy fuel design, core optimization became a central effort. This work is ongoing.

  16. Alloy

    Science.gov (United States)

    Cabeza, Sandra; Garcés, Gerardo; Pérez, Pablo; Adeva, Paloma

    2014-07-01

    The Mg98.5Gd1Zn0.5 alloy produced by a powder metallurgy route was studied and compared with the same alloy produced by extrusion of ingots. Atomized powders were cold compacted and extruded at 623 K and 673 K (350 °C and 400 °C). The microstructure of extruded materials was characterized by α-Mg grains, and Mg3Gd and 14H-LPSO particles located at grain boundaries. Grain size decreased from 6.8 μm in the extruded ingot, down to 1.6 μm for powders extruded at 623 K (350 °C). Grain refinement resulted in an increase in mechanical properties at room and high temperatures. Moreover, at high temperatures the PM alloy showed superplasticity at high strain rates, with elongations to failure up to 700 pct.

  17. Shape memory alloy seals for geothermal applications. Final report. Report ESG-82-14

    Energy Technology Data Exchange (ETDEWEB)

    Friske, Warren H.; Schwartzbart, Harry

    1982-07-30

    A novel temperature-actuated seal for geothermal applications is under development. This program uses the shape memory property of nickel-titanium (Nitinol) alloys to achieve an improved seal in geothermal downhole pumps. Nitinol flange face seals and pump shaft seals have been designed, fabricated, and tested. It has been demonstrated that the shape memory effect of Nitinol alloys can be utilized to activate and maintain a leaktight seal in geothermal environments.

  18. Grain refinement of permanent mold cast copper base alloys. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Sadayappan, M.; Thomson, J. P.; Elboujdaini, M.; Gu, G. Ping; Sahoo, M.

    2004-04-29

    Grain refinement behavior of copper alloys cast in permanent molds was investigated. This is one of the least studied subjects in copper alloy castings. Grain refinement is not widely practiced for leaded copper alloys cast in sand molds. Aluminum bronzes and high strength yellow brasses, cast in sand and permanent molds, were usually fine grained due to the presence of more than 2% iron. Grain refinement of the most common permanent mold casting alloys, leaded yellow brass and its lead-free replacement EnviroBrass III, is not universally accepted due to the perceived problem of hard spots in finished castings and for the same reason these alloys contain very low amounts of iron. The yellow brasses and Cu-Si alloys are gaining popularity in North America due to their low lead content and amenability for permanent mold casting. These alloys are prone to hot tearing in permanent mold casting. Grain refinement is one of the solutions for reducing this problem. However, to use this technique it is necessary to understand the mechanism of grain refinement and other issues involved in the process. The following issues were studied during this three year project funded by the US Department of Energy and the copper casting industry: (1) Effect of alloying additions on the grain size of Cu-Zn alloys and their interaction with grain refiners; (2) Effect of two grain refining elements, boron and zirconium, on the grain size of four copper alloys, yellow brass, EnviroBrass II, silicon brass and silicon bronze and the duration of their effect (fading); (3) Prediction of grain refinement using cooling curve analysis and use of this method as an on-line quality control tool; (4) Hard spot formation in yellow brass and EnviroBrass due to grain refinement; (5) Corrosion resistance of the grain refined alloys; (6) Transfer the technology to permanent mold casting foundries; It was found that alloying elements such as tin and zinc do not change the grain size of Cu-Zn alloys

  19. Molecular engineering of polymer alloys: A final report of results obtained on CRADA No. 1078

    Energy Technology Data Exchange (ETDEWEB)

    Curro, J.G. [Sandia National Labs., Albuquerque, NM (United States); Schweizer, K.S. [Univ. of Illinois, Urbana, IL (United States). Dept. of Materials Science and Engineering; Honeycutt, J.D. [BIOSYM Technologies, San Diego, CA (United States)

    1995-12-01

    This report summarizes the technical progress made in the past three years on CRADA No. 1078, Molecular Engineering of Polymer Alloys. The thrust of this CRADA was to start with the basic ideas of PRISM theory and develop it to the point where it could be applied to modeling of polymer alloys. In this program, BIOSYM, Sandia and the University of Illinois worked jointly to develop the theoretical techniques and numerical formalisms necessary to implement the theoretical ideas into commercial software aimed at molecular engineering of polymer alloys. This CRADA focused on developing the techniques required to make the transition from theory to practice. These techniques were then used by BIOSYM to incorporate PRISM theory and other new developments into their commercial software.

  20. Atomistic studies of grain boundaries and heterophase interfaces in alloys and compounds. Final report, July 1987-August 1998

    Energy Technology Data Exchange (ETDEWEB)

    Vitek, Vaclav

    1998-08-01

    The overarching goal of the research supported by this grant was investigation of the structure and properties of interfaces in multicomponent systems by atomistic modeling. Initially, the research was devoted to studies of segregation to grain boundaries in binary disordered alloys. The next step was then studies of the structure and properties of grain boundaries in ordered compounds, specifically Ni3Al and NiAl, and grain boundary segregation in these compounds in the case of off-stoichiometry. Finally, the structure of Nb/sapphire interfaces, in particular the core configurations of the misfit dislocations, was studied.

  1. Oxidation Behavior of a Refractory NbCrMo0.5Ta0.5TiZr Alloy (Preprint)

    Science.gov (United States)

    2012-03-01

    smaller than the atomic radii of other elements in the fourth alloy, causes additional formation of a minor FCC Laves phase [10]. Due to strongly...pattern of the HIPd NbCrMo0.5Ta0.5TiZr alloy. A major BCC1 phase and two minor phases , BCC2 and FCC ( Laves ), were identified [10]. The lattice parameters...parallel to the sample surface develop in the regions of former BCC2 and Laves phases (between former BCC1 particles). The cracks are also extended

  2. Alloy Thin-films and Surfaces for New Materials. Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Sprunger, P.T.

    2003-08-10

    Within the framework of a DOE National Laboratory/EPSCoR state partnership, investigations by researchers at Louisiana State University and Oak Ridge National Laboratory were focused on revealing the unique nanophase properties of alloy thin-films and bimetallic surfaces. Employing a number of experimental preparation techniques and characterization probes (synchrotron-based angle-resolved and valence/core-level PES and variable-temperature STM/STS), the goal of this program was to elucidate of the interconnecting physical and chemical properties of a variety of alloy surfaces and thin-films, specifically, determining the correlation between atomic structure/composition, electronic structure, and catalytic/chemisorption properties of these nanoscale.

  3. Aging and Phase Stability Studies of Alloy 22 FY08 Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Torres, S G

    2008-04-03

    This report is a compilation of work done over the past ten years in support of phase stability studies of Alloy 22 for the Yucca Mountain Project and contains information previously published, reported, and referenced. Most sections are paraphrased here for the convenience of readers. Evaluation of the fabrication processes involved in the manufacture of waste containers is important as these processes can have an effect on the metallurgical structure of an alloy. Because material properties such as strength, toughness, aging kinetics and corrosion resistance are all dependent on the microstructure, it is important that prototypes be built and evaluated for processing effects on the performance of the material. Of particular importance are welds, which have an as-cast microstructure with chemical segregation and precipitation of complex phases resulting from the welding process. The work summarized in this report contains information on the effects of fabrication processes such as solution annealing, stress mitigation, heat-to-heat variability, and welding on the kinetics of precipitation, mechanical, and corrosion properties. For a waste package lifetime of thousands of years, it is impossible to test directly in the laboratory the behavior of Alloy 22 under expected repository conditions. The changes that may occur in these materials must be accelerated. For phase stability studies, this is achieved by accelerating the phase transformations by increasing test temperatures above those anticipated in the proposed repository. For these reasons, Alloy 22 characterization specimens were aged at Lawrence Livermore National Laboratory (LLNL) Aging Facilities for times from 1 hour up to 8 years at temperatures ranging from 200-750 C. These data as well as the data from specimens aged at 260 C, 343 C, and 427 C for 100,028 hours at Haynes International will be used for performance confirmation and model validation.

  4. Production of small diameter high-temperature-strength refractory metal wires

    Science.gov (United States)

    Petrasek, D. W.; Signorelli, R. A.; King, G. W.

    1973-01-01

    Special thermomechanical techniques (schedules) have been developed to produce small diameter wire from three refractory metal alloys: colombian base alloy, tantalum base alloy, and tungsten base alloy. High strengths of these wires indicate their potential for contributing increased strength to metallic composites.

  5. Mechanical Properties of Low-Density, Refractory Multi-Principal Element Alloys of the Cr-Nb-Ti-V-Zr System (Postprint)

    Science.gov (United States)

    2014-04-01

    these faces were lubricated with boron nitride. The specimen’s dimensions were 4.7 mm4.7 mm7.7 mm. Com pression tests were conducted at 298 K, 873 K...characteristic vein patterns and spherical particles in these regions. Melting of this type has been observed during fracture of amorphous and nano ...of nano or submicron size particles. This work thus suggests a reasoned approach for developing high entropy alloys with both solid solution and

  6. Refractory chronic cluster headache

    DEFF Research Database (Denmark)

    Mitsikostas, Dimos D; Edvinsson, Lars; Jensen, Rigmor H

    2014-01-01

    Chronic cluster headache (CCH) often resists to prophylactic pharmaceutical treatments resulting in patients' life damage. In this rare but pragmatic situation escalation to invasive management is needed but framing criteria are lacking. We aimed to reach a consensus for refractory CCH definition...... for clinical and research use. The preparation of the final consensus followed three stages. Internal between authors, a larger between all European Headache Federation members and finally an international one among all investigators that have published clinical studies on cluster headache the last five years....... Eighty-five investigators reached by email. Proposed criteria were in the format of the International Classification of Headache Disorders III-beta (description, criteria, notes, comments and references). Following this evaluation eight drafts were prepared before the final. Twenty-four (28...

  7. Machine casting of ferrous alloys. Final report, 30 June 1976--30 June 1977

    Energy Technology Data Exchange (ETDEWEB)

    Flemings, M.C.; Young, K.P.; Boylan, J.F.; Bye, R.L.; Santor, M.L.

    1977-06-01

    During this year the basic Rheocasting system, which was fully operational at the beginning of the year, was improved in various ways to increase reliability and productivity. Specific improvements were the addition of a reducing gas in the melting chamber, a shield gas extension nozzle and graphite inserts at the bottom of the Rheocaster to eliminate 'hot spots'. Large quantities of 304 and 440C stainless steel alloys were cast during this period (approximately 800 pounds of 304 and 2000 pounds of 440C) and smaller quantities of other materials were also Rheocast including M2 tool steel, and HS 31 Cobalt base superalloy. Improvements in details and automation of the Thixocasting process were also made during this period. Work subsequently concentrated on casting large quantities of stainless steel into various die materials in order to determine die life and to optimize that die life.

  8. Radiation behavior of high-entropy alloys for advanced reactors. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Liaw, Peter K. [Univ. of Tennessee, Knoxville, TN (United States); Egami, Takeshi [Univ. of Tennessee, Knoxville, TN (United States); Zhang, Chuan [CompuTherm, LLC, Madison, WI (United States); Zhang, Fan [CompuTherm, LLC, Madison, WI (United States); Zhang, Yanwen [Univ. of Tennessee, Knoxville, TN (United States)

    2015-04-30

    In the first task, we have demonstrated the radiation damage and the recrystallization behaviors in multicomponent alloys through molecular-dynamics simulations. It is found that by alloying with atoms of different sizes, the atomic-level strain increases, and the propensity of the radiation-induced crystalline to amorphous transition increases as the defects cluster in the cascade body. Recrystallization of the radiation induced supercooled or glass regions show that by tuning the composition and the equilibrium temperature, the multicomponent alloys can be healed. The crystalline-amorphous-crystalline transitions predict the potential high radiation resistance in multicomponent alloys. In the second task, three types of high-entropy alloys (HEAs) were fabricated from AlCoCrFeNi and AlCuCrFeNi quinary alloys. Hardness and reduced contact modulus were measured using nanoindentation tests. Heavy ion irradiation were performed using 10 MeV gold and 5 MeV nickel to study radiation effects. Al0.5CrCuFeNi2 shows phase separation upon the presence of copper. Both hardness and contact modulus exhibit the same trend as increasing the applied load, and it indicates that excessive free volume may alter the growth rate of the plastic zone. The as-cast Al0.1CoCrFeNi specimen undergone the hot isostatic pressing (HIP) process and steady cooling rate which mitigate the quenching effect. The swelling behavior was characterized by the atomic force microscopy (AFM), and the swelling rate is approximately 0.02% dpa. Selected area diffraction (SAD) patters show irradiation-induced amorphization throughout the ion projected range. Within the peak damage region, an amorpous ring is observed, and a mixture of amorphous/ crystalline structure at deeper depth is found. The Al0.3CoCrFeNi HEAs shows good radiation resistance up to 60 peak dpa. No voids or dislocations are observed. The crystal structures remain face-centered-cubic (FCC) before and

  9. APPRAISAL OF FINAL TAILINGS APPLICABILITY FOR PROCESSING AND PRODUCTION OF MODIFIERS OF IRON-CARBON ALLOYS

    Directory of Open Access Journals (Sweden)

    A. S. Panasugin

    2011-01-01

    Full Text Available The methodology of rating of the galvanic final tailings applicability for further processing in the interests of needs of metallurgical production of the Republic Belarus is offered.

  10. 77 FR 8808 - Circular Welded Non-Alloy Steel Pipe From the Republic of Korea: Extension of the Final Results...

    Science.gov (United States)

    2012-02-15

    ... International Trade Administration Circular Welded Non-Alloy Steel Pipe From the Republic of Korea: Extension of... antidumping duty administrative review of circular welded non-alloy steel pipe from the Republic of Korea, covering the period November 1, 2009, through October 31, 2010. See Circular Welded Non-Alloy Steel...

  11. 76 FR 15941 - Circular Welded Non-Alloy Steel Pipe From the Republic of Korea: Extension of the Final Results...

    Science.gov (United States)

    2011-03-22

    ... International Trade Administration Circular Welded Non-Alloy Steel Pipe From the Republic of Korea: Extension of... antidumping duty administrative review of circular welded non-alloy steel pipe from the Republic of Korea, covering the period November 1, 2008, through October 31, 2009. See Circular Welded Non-Alloy Steel...

  12. Development and Application of Refractory Materials for Molten Aluminum Applications

    Energy Technology Data Exchange (ETDEWEB)

    Hemrick, James Gordon [ORNL; Headrick, William [University of Missouri, Rolla; Peters, Klaus-Markus [ORNL

    2008-01-01

    Two new refractory materials have been developed for use in molten aluminum contact applications which exhibit improved corrosion and wear resistance, along with improved thermal management through reduced heat losses. The development of these materials was based on understanding of the corrosion and wear mechanisms associated with currently used aluminum contact refractories through physical, chemical, and mechanical characterization and analysis performed by Oak Ridge National Laboratory (ORNL) and the University of Missouri, Rolla (UMR) along with their industrial partners, under the ITP Materials project "Multifunctional Metallic and Refractory Materials for Energy Efficient Handling of Molten Metals". Spent castable refractories obtained from a natural gas fired reverberatory aluminum alloy melting furnace were analyzed leading to identification of several refractory degradation mechanisms and strategies to produce improved materials. The newly developed materials have been validated through both R&D industrial trials and independent commercial trials by the refractory manufacturers.

  13. NASA-UVA Light Aerospace Alloy and Structure Technology Program Supplement: Aluminum-Based Materials for High Speed Aircraft. Final report, 1 December 1991-31 March 1996

    Energy Technology Data Exchange (ETDEWEB)

    Starke, E.A. Jr.

    1996-05-01

    This is the final report of the study `Aluminum-Based Materials for high Speed Aircraft` which had the objectives (1) to identify the most promising aluminum-based materials with respect to major structural use on the HSCT and to further develop those materials and (2) to assess the materials through detailed trade and evaluation studies with respect to their structural efficiency on the HSCT. The research team consisted of ALCOA, Allied-Signal, Boeing, McDonnell Douglas, Reynolds Metals and the University of Virginia. Four classes of aluminum alloys were investigated: (1) I/M 2XXX containing Li and I/M 2XXX with Li, (2) I/M 6XXX, (3) two P/M 2XXX alloys and (4) two different aluminum-based metal matrix composites (MMC). The I/M alloys were targeted for a Mach 2.0 aircraft and the P/M and MMC alloys were targeted for a Mach 2.4 aircraft. Design studies were conducted using several different concepts including skin/stiffener (baseline), honeycomb sandwich, integrally stiffened and hybrid adaptations (conventionally stiffened thin-sandwich skins). Alloy development included fundamental studies of coarsening behavior, the effect of stress on nucleation and growth of precipitates, and fracture toughness as a function of temperature were an integral part of this program. The details of all phases of the research are described in this final report.

  14. Characterization of hydrogen ingress in high-strength alloys. Final report, 15 September 1993-14 September 1995

    Energy Technology Data Exchange (ETDEWEB)

    Pound, B.G.

    1995-11-01

    The ingress of hydrogen (H) in various high-strength alloys was investigated with a view to characterizing their susceptibility to hydrogen embrittlement (HE). A potentiostatic pulse technique was applied to three Fe-base alloys (AerMet 100, H11, and A-286), two Cu-containing alloys (Be-Cu and alloy K-500), a superferritic stainless steel (Sea-Cure), and three Beta-Ti alloys (Ti-15V-3Cr-3Al-3Sn, Beta-21S, and Beta-C) in 1 mol/L acetic acid-1 mol/L sodium acetate. The data were analyzed using a diffusion/trapping model to obtain the irreversible trapping constant (k) and H entry flux for each alloy. The order of the k values for AerMet 100, H11, and two high-strength steels previously studied (4340 and 18Ni) inversely parallels their threshold stress intensities for stress corrosion cracking. Likewise, the k values for the other alloys can be correlated with their observed resistances to HE according to the following groups: (1) alloy A-286,18Ni steel, H11, Be-Cu, and also alloy 718 from earlier work; (2) annealed/aged and direct aged alloy K-500; and (3) Ti alloys. The trapping characteristics of Sea-Cure could not be determined. However, the propensity of the S44660 alloy to undergo HE at cathodic protection potentials can be attributed to changes in the oxide that lead to a less restricted entry of H.

  15. Experimental investigation on effective thermal conductivities of refractory alloy honeycomb cores%耐热合金蜂窝等效热导率的实验研究

    Institute of Scientific and Technical Information of China (English)

    赵剑; 谢宗蕻; 李玮; 田江

    2011-01-01

    耐热合金蜂窝夹芯结构是高超音速飞行器热防护系统外面板的理想候选方案.针对Hastelloy X耐热合金蜂窝夹芯结构开展了稳态传热实验,通过控制加热板温度,获得了一组热平衡时蜂窝夹芯结构的热、冷面温度,结合Stefan-Boltzmann定律和大空间自然对流实验关联式,采用热阻分析方法得到了Hastelloy X耐热合金蜂窝随温度变化的宏观等效热导率,并采用Swan-Pittman半经验模型预测了该蜂窝的等效热导率,与实验结果对比一致性较好.%The honeycomb sandwich structures made of heat resistant alloy are suitable for the outer panels of thermal protection system used in hypersonic applications. Static heat transfer experiment was conducted on the Hastelloy X honeycomb sandwich structure, and both the upper and lower face sheet temperatures at steady state were obtained. The macroscopic effective thermal conductivities varying with different temperatures were acquired based on the thermal resistance analytical method, in combination with Stefan-Boltzmanns law and experimental correlation formula for natural convection in infinite space. Swan-Pittman semi-empirical model was adopted to predict the effective thermal conductivities of the Hastelloy X honeycomb sandwich structure, and the comparison between experimental results and predicted results shows good conformity.

  16. RESEARCH ON REFRACTORY SUPERALLOYS IN THE HTM 21 PROJECT

    Institute of Scientific and Technical Information of China (English)

    Y.F.Gu; Y.Yamabe-Mitarai; C.Huang; H.Harada

    2005-01-01

    It was proposed that a new class of alloys based on platinum group metals (PGMs) were called refractory superalloys.These refractory superalloys have an fcc and LI2 coherent two-phase structure (similar to that of Ni-based superalloys), high melting temperatures and good potential as structural materials used at temperatures up to 1800℃.Our recent results on the microstructure evolution, deformation and fracture behavior of some of these refracotry superalloys, especial Ir- and Rh-base refractory superalloys were reported.

  17. Dental devices: classification of dental amalgam, reclassification of dental mercury, designation of special controls for dental amalgam, mercury, and amalgam alloy; technical amendment. Final rule; technical amendment.

    Science.gov (United States)

    2010-06-11

    The Food and Drug Administration (FDA) published a final rule in the Federal Register of August 4, 2009 (74 FR 38686) which classified dental amalgam as a class II device, reclassified dental mercury from class I to class II, and designated special controls for dental amalgam, mercury, and amalgam alloy. The effective date of the rule was November 2, 2009. The final rule was published with an inadvertent error in the codified section. This document corrects that error. This action is being taken to ensure the accuracy of the agency's regulations.

  18. Reaction-Forming Method for Producing Near Net-Shape Refractory Metal Carbides

    Energy Technology Data Exchange (ETDEWEB)

    Palmisiano, Marc N.; Jakubenas, Kevin J.; Baranwal, Rita

    2004-07-20

    A method for reaction forming refractory metal carbides. The method involves the fabrication of a glassy carbon preform by casting an organic, resin-based liquid mixture into a mold and subsequently heat treating it in two steps, which cures and pyrolizes the resin resulting in a porous carbon preform. By varying the amounts of the constituents in the organic, resin-based liquid mixture, control over the density of the carbon preform is obtained. Control of the density and microstructure of the carbon preform allows for determination of the microstructure and properties of the refractory metal carbide material produced. The glassy carbon preform is placed on a bed of refractory metal or refractory metal--silicon alloy. The pieces are heated above the melting point of the metal or alloy. The molten metal wicks inside the porous carbon preform and reacts, forming the refractory metal carbide or refractory metal carbide plus a minor secondary phase.

  19. Chemical thermodynamics of metallic alloy formation. Final report. [Na-K; Mg-Cd; NaCl-NaBr

    Energy Technology Data Exchange (ETDEWEB)

    Wallace, W.E.

    1951-12-01

    Methods and apparatus required in determining the heats of formation at 25/sup 0/C of sodium-potassium alloys, magnesium-cadmium alloys and sodium chloride-sodium bromide ionic solid solutions have been developed. Method for determining free energies of formation of magnesium-cadmium alloys at elevated temperatures has been developed. Apparatus for determining the specific heats of magnesium-cadmium alloys at low temperatures has been prepared. The heat of reaction of pure potassium with water was determined. Provisional values for the heats of formation of four sodium-potassium alloys were obtained. A density-composition curve for magnesium-cadmium alloys was constructed. Heats of formation of nine NaCl-NaBr solid solutions were measured and the data used to calculate thermodynamically the phase diagram describing the mutual solid solubility of the two salts. Lattice spacings of NaCl-NaBr solid solutions were determined by x-ray diffraction techniques and the results compared with Vegnard's Rule and the additivity rule for molar volumes. A theoretical study based upon the Born-Mayer model for ionic solids was made to attempt to account for the variation with composition of the energy and lattice spacings of the alkali halide solid solutions. Comparison of results for the NaCl-NaBr system with those obtained in a similar study of Fontell indicated some discrepancies which were removed by a retreatment of Fontell's data.

  20. Developing Refractories for Exporting

    Institute of Scientific and Technical Information of China (English)

    PANShang-xin

    1996-01-01

    The total output of China refractory products and export volume of China refractory raw materials rank the first in the world,In future the task is to improve the quality of the products to enlarge the variety and to expand export.

  1. Silica Refractory Bricks

    Institute of Scientific and Technical Information of China (English)

    Yu Lingyan; Peng Xigao

    2011-01-01

    @@ 1.Scope This standard specifies the classification,technical requirements,test methods,quality appraisal procedures,packing,marking,transportation,storage,and quality certificate of silica refractory bricks.This standard is applicable to silica refractory bricks with single weight≤40 kg.

  2. Dental devices: classification of dental amalgam, reclassification of dental mercury, designation of special controls for dental amalgam, mercury, and amalgam alloy. Final rule.

    Science.gov (United States)

    2009-08-01

    The Food and Drug Administration (FDA) is issuing a final rule classifying dental amalgam into class II, reclassifying dental mercury from class I to class II, and designating a special control to support the class II classifications of these two devices, as well as the current class II classification of amalgam alloy. The three devices are now classified in a single regulation. The special control for the devices is a guidance document entitled, "Class II Special Controls Guidance Document: Dental Amalgam, Mercury, and Amalgam Alloy." This action is being taken to establish sufficient regulatory controls to provide reasonable assurance of the safety and effectiveness of these devices. Elsewhere in this issue of the Federal Register, FDA is announcing the availability of the guidance document that will serve as the special control for the devices.

  3. Development of improved refractories

    Energy Technology Data Exchange (ETDEWEB)

    Wereszczak, A.A.; Ferber, M.K.; Liu, K.C. [Oak Ridge National Lab., TN (United States); Moore, R.E. [Univ. of Missouri, Rolla, MO (United States)

    1997-04-01

    The goal of the proposed project is to provide expertise and facilities for the high temperature mechanical properties characterization of refractory materials which are of interest to the US DOE`s Office of Industrial Technologies Advanced Industrial Materials Project. Initially the project would establish dedicated refractory testing facilities which would be capable of generating representative engineering creep and high temperature modulus of elasticity (MOE) data to a temperature of 3300{degrees}F (1815{degrees}C) in ambient air. The generated engineering creep and MOE data would serve R&D requirements of refractories-manufacturers and its glass-manufacturer end-users and designers. The relevance of this effort to the refractory and glass-making industries would be ensured by coordinating the research activities through a membership with Alfred University`s Center for Glass Research (CGR) Satellite Center at the University of Missouri-Rolla (UMR), an NSF Center. Valid engineering creep and high temperature MOE data currently do not exist for almost all commercial refractories. Refractory end-users such as glass-manufacturers require such data for efficient and economical design of their various glass-melting furnace superstructures (e.g., furnace crowns). Refractories in glass production furnaces may be subjected to extreme temperatures as high as 3200{degrees}F (1760{degrees}C). With the simultaneous imposition of mechanical and thermal stresses, creep deformation of the refractory material will assuredly occur as a consequence. Designers must ensure that the structural integrity is maintained, so these high temperature deformations must be considered for successful glass furnace superstructure design. These criteria can only be satisfied with the utilization of representative engineering creep and high temperature MOE data for the refractory materials that are chosen for the design of the refractory superstructures.

  4. Refractory migraine in a headache clinic population

    Directory of Open Access Journals (Sweden)

    Fernandez-Torron Roberto

    2011-08-01

    Full Text Available Abstract Background Many migraineurs who seek care in headache clinics are refractory to treatment, despite advances in headache therapies. Epidemiology is poorly characterized, because diagnostic criteria for refractory migraine were not available until recently. We aimed to determine the frequency of refractory migraine in patients attended in the Headache Unit in a tertiary care center, according to recently proposed criteria. Methods The study population consisted of a consecutive sample of 370 patients (60.8% females with a mean age of 43 years (range 14-86 evaluated for the first time in our headache unit over a one-year period (between October 2008 and October 2009. We recorded information on clinical features, previous treatments, Migraine Disability Assessment Score (MIDAS, and final diagnosis. Results Overall migraine and tension-type headache were found in 46.4% and 20.5% of patients, respectively. Refractory migraine was found in 5.1% of patients. In refractory migraineurs, the mean MIDAS score was 96, and 36.8% were medication-overusers. Conclusions Refractory migraine is a relatively common and very disabling condition between the patients attended in a headache unit. The proposed operational criteria may be useful in identifying those patients who require care in headache units, the selection of candidates for combinations of prophylactic drugs or invasive treatments such as neurostimulation, but also to facilitate clinical studies in this patient group.

  5. Refractory metals fabrication technology as applied to fusion reactors

    Energy Technology Data Exchange (ETDEWEB)

    1976-07-01

    Activities are reported in research programs on inspection and fabricion of refractory metals and alloys including those of Mo, Nb, Ta, and V. Progress is summarized in sections on blanking, edge preparation, machining, forming, joining, cleaning, thermal processing, and coating. (JRD)

  6. Final report on in-reactor tensile tests on OFHC - Copper and CuCrZr alloy

    DEFF Research Database (Denmark)

    Singh, B.N; Edwards, D.J.; Tähtinen, S.

    2004-01-01

    of uniaxial tensile tests on pure copper and a CuCrZr alloy in a fission reactor at 363 and 393K. In the following, we first describe the experiments and then present results illustrating the build up ofstress as a function of concurrently increasing strain and displacement dose level. Results on both pre...

  7. Final report on in-reactor creep-fatigue deformation behaviour of a CuCrZr alloy: COFAT 2

    DEFF Research Database (Denmark)

    Singh, Bachu Narain; Johansen, Bjørn Sejr; Tähtinen, S.

    The main objective of the present work was to determine experimentally the mechanical response and resulting microstructural changes in CuCrZr (HT1) alloy exposed concurrently to flux of neutrons and creep-fatigue cyclic loading directly in a fission reactor. Using specially designed test...

  8. Final report on characterization of physical and mechanical properties of copper and copper alloys before and after irradiation

    DEFF Research Database (Denmark)

    Singh, B.N.; Tähtinen, S.

    2002-01-01

    The present report summarizes and highlights the main results of the work carried out during the last 5-6 years on effects of neutron irradiation on physical and mechanical properties of copper and copper alloys. The work was an European contribution toITER Research and Development programme...... amount of further effort is needed to find a realistic and optimum solution....

  9. Development of wire drawing processes for refractory metal fibers

    Science.gov (United States)

    King, G. W.

    1972-01-01

    Fabrication schedules were developed for producing wire, 0.25 mm to 0.51 mm diameter, from the refractory metal alloys ASTAR-811C, B-88 and W-Hf-C. Tensile properties were evaluated at room temperature and up to 1204 C. Also, the stress rupture properties of the alloys at 1093 C were determined. W-Hf-C and B-88 were found to have the best mechanical properties on a strength to density basis. The fabrication schedules for producing wire from these two alloys were further improved with regards to the wire quality and material yield under the optimization of fabrication schedule.

  10. Fireclay Refractory Bricks

    Institute of Scientific and Technical Information of China (English)

    Zhang Xiaohui

    2010-01-01

    @@ 1 Scope This standard specifies the classification,brand,shape,dimension,technical requirements,test methods,quality appraisal procedures,packing,marking,transportation,storage,and quality certificate of fireclay refractory bricks.

  11. Refractory duodenal ulcer

    Directory of Open Access Journals (Sweden)

    Al Freihi Hussein

    1995-01-01

    Full Text Available Refractory or intractable ulcer is defined as an ulcer that fails to heal completely after eight to twelve weeks, despite appropriate treatment with a modern antiulcer therapy in a compliant patient. Refractory ulcer should be suspected in individuals diagnosed to have peptic ulcer if their symptoms persist longer than usual: occurrence of complications or simply their ulcers fail to heal, since up to 25% of such patients remain asymptomatic. Conditions associated with refractory ulcer include noncompliance, continuous consumption of nonsteroidal anti-inflam-matory drugs, acid hypersecretion, smoking. male gender and other factors with questionable role like advanced age, large ulcer size, prolonged duration of symptoms and the presence of complication like bleeding. Nonpeptic ulcers like tuberculosis, malignancy, Crohn′s disease and primary intestinal lymphoma should always be considered in the differential diagnosis. Colonization with H. pylori which is well-known as a cause of frequent recurrences, has not been linked with refractoriness. Patients with refractory ulcers must undergo thorough re-evaluation including repeated endoscopies, obtaining biopsies for microbiology and histology and determination of serum-gastrin level. Once diseases with identifiable etiologies have been ruled out, aggressive medical management with single or multiple antiulcer drugs should be instituted. Such treatments will virtually heal all refractory ulcers. Surgery should be reserved for patients whose ulcers fail to respond to optimal medical therapy or those who develop com-plications necessitating surgical intervention.

  12. Metastability and Delta-Phase Retention in Plutonium Alloys Final Report of LDRD Project 01-ERD-029

    Energy Technology Data Exchange (ETDEWEB)

    Wong, J; Schwartz, A J; Blobaum, K M; Krenn, C R; Wall, M A; Wolfer, W G; Haslam, J J; Moore, K T

    2004-02-11

    The {delta} to {alpha}' phase transformation in Pu-Ga alloys is intriguing for both scientific and technological reasons. On cooling, the ductile fcc {delta}-phase transforms martensitically to the brittle monoclinic {alpha}'-phase at approximately -120 C (depending on composition). This exothermic transformation involves a 20% volume contraction and a significant increase in resistivity. The reversion of {alpha}' to {delta} involves a large temperature hysteresis beginning just above room temperature. In an attempt to better understand the underlying thermodynamics and kinetics responsible for these unusual features, we have investigated the {delta} {leftrightarrow} {alpha}' phase transformations in a Pu-0.6 wt% Ga alloy using a combination of experimental and modeling techniques.

  13. Textures in Strip-Cast Aluminum Alloys: Their On-Line Monitoring and Quantitative Effects on Formability. Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Man, Chi-Sing

    2003-07-27

    Aluminum sheets produced by continuous casting (CC) provide energy and economic savings of at least 25 and 14 percent, respectively, over sheets made from conventional direct chill (DC) ingot casting and rolling. As a result of the much simpler production route in continuous casting, however, the formability of CC aluminum alloys is often somewhat inferior to that of their DC counterparts. The mechanical properties of CC alloys can be improved by controlling their microstructure through optimal thermomechanical processing. Suitable annealing is an important means to improve the formability of CC aluminum alloy sheets. Recrystallization of deformed grains occurs during annealing, and it changes the crystallographic texture of the aluminum sheet. Laboratory tests in this project showed that this texture change can be detected by either laser-ultrasound resonance spectroscopy or resonance EMAT (electromagnetic acoustic transducer) spectroscopy, and that monitoring this change allows the degree of recrystallization or the ''recrystallized fraction'' in an annealed sheet to be ascertained. Through a plant trial conducted in May 2002, this project further demonstrated that it is feasible to monitor the recrystallized state of a continuous-cast aluminum sheet in-situ on the production line by using a laser-ultrasound sensor. When used in conjunction with inline annealing, inline monitoring of the recrystallized fraction by laser-ultrasound resonance spectroscopy offers the possibility of feed-back control that helps optimize processing parameters (e.g., annealing temperature), detect production anomalies, ensure product quality, and further reduce production costs of continuous-cast aluminum alloys. Crystallographic texture strongly affects the mechanical anisotropy/formability of metallic sheets. Clarification of the quantitative relationship between texture and anisotropy/formability of an aluminum alloy will render monitoring and control of its

  14. RHI Refractories Opens Dalian Plant

    Institute of Scientific and Technical Information of China (English)

    Stefan Pirker

    2004-01-01

    @@ End of November the opening ceremony of the RHI Refractories Dalian plant took place in the presence of 250 guests from China and Europe. RHI Refractories welcomed highly official guests from the Dalian City and the Dalian Development Area, the Supervisory Board of RHI, the company's biggest shareholder, the Board of Management, representatives of customers in China as well as Professors of China's refractory academic field. The ceremony' s highlight was the speech of Professor Zhong Xiangchong from Zhengzhou University, member of the China Academy of Science, who pointed out RHI Refractories' long and successful history of refractory innovations during the last decades and the future possibilities of collaboration with RHI Refractories.

  15. Refractory peptic ulcer disease.

    Science.gov (United States)

    Napolitano, Lena

    2009-06-01

    Refractory PUD is a diagnostic and therapeutic challenge. Optimal management of severe or refractory PUD requires a multidisciplinary team approach, using primary care providers, gastroenterologists, and general surgeons. Medical management has become the cornerstone of therapy. Identification and eradication of H pylori infection combined with acid reduction regimens can heal ulceration and also prevent recurrence. Severe, intractable or recurrent PUD and associated complications mandates a careful and methodical evaluation and management strategy to determine the potential etiologies and necessary treatment (medical or surgical) required.

  16. Barrier Coatings for Refractory Metals and Superalloys

    Energy Technology Data Exchange (ETDEWEB)

    SM Sabol; BT Randall; JD Edington; CJ Larkin; BJ Close

    2006-02-23

    In the closed working fluid loop of the proposed Prometheus space nuclear power plant (SNPP), there is the potential for reaction of core and plant structural materials with gas phase impurities and gas phase transport of interstitial elements between superalloy and refractory metal alloy components during service. Primary concerns are surface oxidation, interstitial embrittlement of refractory metals and decarburization of superalloys. In parallel with kinetic investigations, this letter evaluates the ability of potential coatings to prevent or impede communication between reactor and plant components. Key coating requirements are identified and current technology coating materials are reviewed relative to these requirements. Candidate coatings are identified for future evaluation based on current knowledge of design parameters and anticipated environment. Coatings were identified for superalloys and refractory metals to provide diffusion barriers to interstitial transport and act as reactive barriers to potential oxidation. Due to their high stability at low oxygen potential, alumina formers are most promising for oxidation protection given the anticipated coolant gas chemistry. A sublayer of iridium is recommended to provide inherent diffusion resistance to interstitials. Based on specific base metal selection, a thin film substrate--coating interdiffusion barrier layer may be necessary to meet mission life.

  17. ZIRCONIUM-TITANIUM-BERYLLIUM BRAZING ALLOY

    Science.gov (United States)

    Gilliland, R.G.; Patriarca, P.; Slaughter, G.M.; Williams, L.C.

    1962-06-12

    A new and improved ternary alloy is described which is of particular utility in braze-bonding parts made of a refractory metal selected from Group IV, V, and VI of the periodic table and alloys containing said metal as a predominating alloying ingredient. The brazing alloy contains, by weight, 40 to 50 per cent zirconium, 40 to 50 per cent titanium, and the balance beryllium in amounts ranging from 1 to 20 per cent, said alloy having a melting point in the range 950 to 1400 deg C. (AEC)

  18. Final report on in-reactor uniaxial tensile deformation of pure iron and Fe-Cr alloy

    DEFF Research Database (Denmark)

    Singh, Bachu Narain; Huang, X.; Tähtinen, S.

    of materials used in the structural components of a fission or fusion reactor where the materials will be exposed concurrently to displacement damage and external and/or internal stresses. In an effort to evaluate and understand the dynamic response of materials under these conditions, we have recently...... performed a series of uniaxial tensile tests on Fe-Cr and pure iron specimens in the BR-2 reactor at Mol (Belgium). The present report first provides a brief description of the test facilities and the procedure used for performing the in-reactor tests. The results on the mechanical response of materials...... and deformed, irradiated and undeformed, post-irradiation deformed and the in-reactor deformed specimens are also described. During the in-reactor tests the specimens of both Fe-Cr alloy and pure iron deform in a homogeneous manner and do not exhibit the phenomenon of yield drop. An increase in the pre...

  19. Dynamic Testing of Gasifier Refractory

    Energy Technology Data Exchange (ETDEWEB)

    Michael D. Mann; Wayne S. Seames; Devdutt Shukla; Xi Hong; John P. Hurley

    2005-12-01

    The University of North Dakota (UND) Chemical Engineering Department in conjunction with the UND Energy & Environmental Research Center (EERC) have initiated a program to examine the combined chemical (reaction and phase change) and physical (erosion) effects experienced by refractory materials under slagging coal gasification conditions. The goal of this work is to devise a mechanism of refractory loss under these conditions. The controlled-atmospheric dynamic corrodent application furnace (CADCAF) was utilized to simulate refractory/slag interactions under dynamic conditions that more realistically simulate the environment in a slagging coal gasifier than any of the static tests used previously by refractory manufacturers and researchers. High-alumina and high-chromia refractory bricks were tested using slags obtained from two solid fuel gasifiers. Testing was performed at 1475 C in a reducing atmosphere (2% H{sub 2} in N{sub 2}) The CADCAF tests show that high-chrome refractories have greater corrosion resistance than high-aluminum refractories; coal slag readily diffuses into the refractory through its grain boundaries; the refractory grains are more stable than the matrix in the tests, and the grains are the first line of defense against corrosion; calcium and alkali in the slag are more corrosive than iron; and silicon and calcium penetrate the deepest into the refractory. The results obtained from this study are preliminary and should be combined with result from other research programs. In particular, the refractory corrosion results from this study should be compared with refractories removed from commercial gasifiers.

  20. Refractory Minerals in Henan Province

    Institute of Scientific and Technical Information of China (English)

    JIN Qinguo; LI Jing; LIU Jiehua; LIU Yanjun

    2004-01-01

    Henan province is very rich in refractory minerals of many varieties including silica, dolomite, graphite,pearlite, sepiolite, olivine, and sillimanite group minerals, besides the abundant reserves of fireclay and bauxite,which lay a good foundation for the development of the refractories industry of the province. The paper introduces the reserves, distribution and character of the refractory minerals in Henan province.

  1. Status epilepticus: Refractory and super-refractory.

    Science.gov (United States)

    Dubey, Deepanshu; Kalita, Jayantee; Misra, Usha K

    2017-01-01

    Status epilepticus (SE) is an important neurological emergency. It is defined as seizures lasting for 5 minutes or more or recurrent seizures without recovery of consciousness to baseline between the attacks. Refractory SE (RSE) is defined as SE persisting despite sufficient dose of benzodiazepines and at least one antiepileptic drug (AED), irrespective of time. Super refractory SE (SRSE) is defined as SE that continues for 24 hours or more after the use of anesthetic therapy, including cases that recur on weaning of the anesthestic agent. RSE occurs in 23%-48% of the patients and SRSE in approximately 22% of the patients with SE. In general, RSE occurs in patients with new-onset seizures rather than in patients with chronic epilepsy. The etiology of RSE in developing countries is dominated by central nervous system (CNS) infections and head injury compared to stroke and drug withdrawal in the developed countries. The treatment of RSE and SRSE is not evidence based. Following benzodiazepines, the second line antiepileptic drugs include sodium valproate, phenytoin, levetiracetam, and anesthetic drugs such as midazolam, phenobarbital, and propofol. Most intravenous anesthetic drugs produce hypotension and respiratory suppression; therefore, patients with RSE are managed in intensive care units (ICUs). In RSE patients, electroencephalogram (EEG) burst suppression with interburst interval of 2-20 s or even flat EEG has been tried. Recently, concerns have been raised on the safety of burst suppression in RSE and SRSE. The paucity of ICUs in developing countries limits the use of these management protocols. There is a need to explore intravenous AEDs with safer cardiovascular and respiratory profile for the management of SE.

  2. Refractory headache: classification and nomenclature.

    Science.gov (United States)

    Levin, Morris

    2008-06-01

    There are a number of reasons to attempt to define and classify refractory headache disorders. Particularly important are the potential benefits in the areas of research, treatment, and medical cost reimbursement. There are challenges in attempting to classify refractory forms of headaches, including the lack of biological or other objective markers and a lack of consensus among practitioners as to what qualifies as refractoriness, or even if a separate category for refractory migraine and other refractory headaches needs to be established. A definition of refractory migraine has been proposed by Schulman et al in this issue ("Defining Refractory Migraine [RM] and Refractory Chronic Migraine [RCM]: Proposed Criteria for the Refractory Headache Special Interests Section of the American Headache Society"), which should be tested for validity and usefulness. It seems reasonable to consider adding this defined syndrome to the International Classification of Headache Disorders, second edition (ICHD-II). In this article, options for adding refractory headache syndromes to the ICHD are discussed with pros and cons for each. Two "best" options for adding the disorder "refractory migraine" to the ICHD are presented along with an illustrative case example.

  3. Investigation of Appropriate Refractory Material for Laboratory Electritic Resistrance Furnance

    Directory of Open Access Journals (Sweden)

    J.B Agboola

    2009-07-01

    Full Text Available There have been numerous efforts to increase the local content of furnaces; hence the choice of appropriate refractory material for lining of locally manufactured furnaces has remained a major concern. This research work investigates the choice of appropriate local refractory material for the lining of laboratory electric resistance furnace.Electric resistance furnaces are extensively used in the laboratory for heat treatment of metals and alloys. Refractory binders such as silicon carbide were experimented upon for strength and resistance to high temperature.The results obtained showed that Kankara fireclay containing 15% SiC ( 5.70 % linear shrinkage , 46.2% apparent porosity, 1.77gkm³ Bulk density, 18 cycles of spalling tests at 1300°C, 5.253KN/m² of cold strength has appropriate properties for producing grooved bricks for lining of laboratory electric resistance Furnace.

  4. Ab initio Based Modeling of Radiation Effects in Multi-Component Alloys: Final Scientific/Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Dane Morgan

    2010-06-10

    The project began March 13, 2006, allocated for three years, and received a one year extension from March 13, 2009 to March 12, 2010. It has now completed 48 of 48 total months. The project was focused on using ab initio methods to gain insights into radiation induced segregation (RIS) in Ni-Fe-Cr alloys. The project had the following key accomplishments • Development of a large database of ab initio energetics that can be used by many researchers in the future for increased understanding of this system. For example, we have the first calculations showing a dramatic stabilization effect of Cr-Cr interstitial dumbbells in Ni. • Prediction of both vacancy and interstitial diffusion constants for Ni-Cr and Ni-Fe for dilute Cr and Fe. This work included generalization of widely used multifrequency models to make use of ab initio derived energetics and thermodynamics. • Prediction of qualitative trends of RIS from vacancy and interstitial mechanisms, suggesting the two types of defect fluxes drive Cr RIS in opposite directions. • Detailed kinetic Monte Carlo modeling of diffusion by vacancy mechanism in Ni-Cr as a function of Cr concentration. The results demonstrate that Cr content can have a significant effect on RIS. • Development of a quantitative RIS transport model, including models for thermodynamic factors and boundary conditions.

  5. 76 FR 44304 - Circular Welded Non-Alloy Steel Pipe From the Republic of Korea: Amended Final Results of the...

    Science.gov (United States)

    2011-07-25

    ... ministerial error in the cash deposit rate assigned to the company. No rebuttal comments were received. Final..., instead, assigned to Hyundai HYSCO the cash deposit rate for other companies not selected for individual..., we do not assign that company a new cash deposit rate. Additionally, when the company had no...

  6. Research on silicon-carbon alloys and interfaces. Final subcontract report, 15 February 1991--31 July 1994

    Energy Technology Data Exchange (ETDEWEB)

    Abelson, J.R. [Illinois Univ., Urbana, IL (United States)

    1995-07-01

    This report describes work performed to develop improved p-type wide-band-gap hydrogenated amorphous silicon-carbon alloy (a-Si{sub 1-x}C{sub x:}H) thin films and interfaces for the ``top junction`` in hydrogenated amorphous silicon (a-Si:H)-based p-i-n solar cells. We used direct current reactive magnetron sputtering to deposit undoped a-Si{sub 1-x}C{sub x}H films with a Tauc band gap E{sub g} of 1.90 eV, a sub-band-gap absorption of 0.4 (at 1.2 eV), an Urbach energy of 55 MeV, an ambipolar diffusion length of 100 nm, an air-mass-one photoconductivity of 10{sup {minus}6}/{Omega}-cm, and a dark conductivity of 8{times} 1O{sup {minus}11}/{Omega}-cm. p{sup +}a-Si{sub 1-x}C{sub x}:H films with a Tauc band gap of 1.85 eV have a dark conductivity of 8 {times} 10{sup {minus}6}/{Omega}-cm and thermal activation energy of 0.28 eV. We used in-situ spectroscopic ellipsometry and post-growth X-ray photoelectron spectroscopy to determine the relative roles of H and Si in the chemical reduction of SnO{sub 2} in the early stages of film growth. We used in-situ spectroscopic ellipsometry to show that a-Si:H can be transformed into {mu}c-Si:H in a subsurface region under appropriate growth conditions. We also determined substrate cleaning and ion bombardment conditions which improve the adhesion of a-Si{sub 1-x}C{sub x}:H films.

  7. Refractory gastroesophageal reflux disease

    OpenAIRE

    Joaquim Prado P. Moraes-Filho

    2012-01-01

    CONTEXT: Gastroesophageal reflux disease (GERD) is a condition which develops when the reflux of stomach contents causes troublesome symptoms and/or complications. Its pathophysiology, diagnosis and treatment have frequently been analyzed but it is interesting to review some aspects of the GERD refractory patients to the proton pump inhibitors treatment. The treatment encompasses behavioral measures and pharmacological therapy. The majority of the patients respond well to proton pump inhibito...

  8. Colectomy for refractory constipation

    DEFF Research Database (Denmark)

    Raahave, Dennis; Loud, Franck Bjørn; Christensen, Elsebeth;

    2010-01-01

    OBJECTIVE: This study evaluated the type of colectomy, postoperative complications, functional results, and satisfaction in patients with constipation refractory to conservative therapy. Further, colonic transit time (CTT), faecal load (coprostasis), and colon length (redundancies) were compared...... had at hemicolectomy, 11 patients a subtotal colectomy and 3 patients an ileostomy. Two patients had an anastomotic leak and one died. In 11 patients, further surgery was necessary, because of recurrent constipation. Abdominal pain disappeared and defecation patterns improved significantly to 1-4 per...

  9. Refractory status epilepticus

    Directory of Open Access Journals (Sweden)

    Sanjay P Singh

    2014-01-01

    Full Text Available Refractory status epilepticus is a potentially life-threatening medical emergency. It requires early diagnosis and treatment. There is a lack of consensus upon its semantic definition of whether it is status epilepticus that continues despite treatment with benzodiazepine and one antiepileptic medication (AED, i.e., Lorazepam + phenytoin. Others regard refractory status epilepticus as failure of benzodiazepine and 2 antiepileptic medications, i.e., Lorazepam + phenytoin + phenobarb. Up to 30% patients in SE fail to respond to two antiepileptic drugs (AEDs and 15% continue to have seizure activity despite use of three drugs. Mechanisms that have made the treatment even more challenging are GABA-R that is internalized during status epilepticus and upregulation of multidrug transporter proteins. All patients of refractory status epilepticus require continuous EEG monitoring. There are three main agents used in the treatment of RSE. These include pentobarbital or thiopental, midazolam and propofol. RSE was shown to result in mortality in 35% cases, 39.13% of patients were left with severe neurological deficits, while another 13% had mild neurological deficits.

  10. Wetting and Reaction Characteristics of Al2O3/SiC Composite Refractories

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Jing [ORNL; Hemrick, James Gordon [ORNL; Peters, Klaus-Markus [ORNL; Liu, Xingbo [ORNL; Barbero, Ever J [ORNL

    2007-01-01

    The reactive wetting behavior of three types of alumina-silicon carbide composite refractory materials was investigated in contact with molten aluminum (Al) and Al alloy using an optimized sessile drop method at 900oC in a purified Ar-4% H2 atmosphere. The time dependent behavior of contact angle and droplet geometry was monitored and the wetting kinetics was identified. The initial contact angle between the liquid Al/Al alloy and two of the refractory substrates was found to be an obtuse angle, which gradually changed to a 90o angle and then eventually to an acute angle with time. However, the wetting angle for the third refractory substrate was found to stay at an obtuse angle for the entire two-hour duration of the experiment. The difference in wetting properties among three types of refractories is attributed to be due to their microstructural and compositional variations. The significant effect of the alloying magnesium added to the molten Al alloy droplets in regard to the wetting kinetics and the influence on the reaction with the refractory substrates is discussed. The results obtained provide important understanding on the wetting and corrosion mechanisms of alumina and silicon carbide materials in contact with molten aluminum.

  11. Ensuring and improving corrosion resistance in high-alloy welds. Final report; Sicherung und Steigerung der Korrosionsbestaendigkeit hochlegierter Schweissverbindungen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-12-22

    The welding process of the two high-alloy austenitic steels X5CrNiMo17 12 2 (1.4404) and X1NiCrMoCuN25 20 5 (1.4539) and the subsequent maintenance of the welds were to be optimized. This comprised detailed investigations into the interdependence between welding technologies and surface treatment. Systematic investigations showed that even with optimized processes, welding involves considerable stress to the materials, leading to structural changes, higher intrinsic stress and tarnish layers. Investigations of surface finishing processes showed that the finishing process and tools have significant effect on corrosion. (orig.) [German] Das Forschungsvorhaben hatte zum Ziel, neben der Optimierung des Schweissprozesses der beiden hochlegierten austenitischen Staehle X5CrNiMo17 12 2 (1.4404) und X1NiCrMoCuN25 20 5 (1.4539), eine auf den Schweissprozess abgestimmte ''Nachsorge'' zu optimieren. Das heisst, dass die Zusammenhaenge zwischen der jeweiligen Schweisstechnologie und der Oberflaechennachbehandlung in ihrer Vielschichtigkeit grundlegend untersucht werden sollen. Es konnte anhand von systematischen schweisstechnischen und werkstofftechnischen Untersuchungen gezeigt werden, dass auch nach einer umfassenden Optimierung des Schweissprozesses das Schweissen fuer den Werkstoff eine erhebliche Beeinflussung darstellt. Es kommt zu Gefuegeveraenderungen, zur Erhoehung der Eigenspannungen und zur Ausbildung von Anlaufschichten. Diese durch das Schweissen bedingten Effekte ueben allesamt einen grossen Einfluss auf das Korrosionsverhalten aus. Weder durch die Optimierung der Schweissparameter (z. B. Streckenenergie) noch durch die Wahl der Art des zu verwendenen Schutz- bzw. Wurzelschutzgases kann die Ausbildung der Anlaufschichten und eine daraus resultierende Veraenderung der Korrosionsbestaendigkeit verhindert werden. Das Korrosionsverhalten laesst sich jedoch positiv z.B. durch die Art des Schutzgases bei Einhaltung der optimierten Schweissparameter

  12. Final Report on in-reactor creep-fatigue deformation behaviour of a CuCrZr alloy: COFAT 1

    Energy Technology Data Exchange (ETDEWEB)

    Singh, B.N. [Risoe National Lab. - DTU, Materials Research Dept., Roskilde (Denmark); Taehtinen, S.; Moilanen, P. [VTT Industrial Systems (Finland); Jacquet, P.; Dekeyser, J. [SCK-CEN, Reactor Technology Design Dept., Mol (Belgium); Edwards, D.J. [Pacific Northwest National Lab., Reactor Technology Design Dept., Richland (United States); Li, M. [Oak Ridge National Lab., Materials Science and Technology Div., Oak Ridge, Tennessee (United States); Stubbins, J.F. [Univ. of Illinois, Dept. of Nuclear, Plasma and Radiological Engineering, Urbane, Illinois (United States)

    2007-08-15

    At present, practically nothing is known about the deformation behaviour of materials subjected simultaneously to external cyclic force and neutron irradiation. The main objective of the present work is to determine experimentally the mechanical response and resulting microstructural changes in CuCrZr(HT1) alloy exposed concurrently to flux of neutrons and creep-fatigue cyclic loading directly in a fission reactor. Special experimental facilities were designed and fabricated for this purpose. A number of in-reactor creep-fatigue experiments were successfully carried out in the BR-2 reactor at Mol (Belgium). In the present report we first describe the experimental facilities and the details of the in-reactor creep-fatigue experiments carried out at 363 and 343K at a strain amplitude of 0.5% with hold-times of 10 and 100s, respectively. For comparison purposes, similar creep-fatigue tests were performed outside of the reactor. (i.e. in the absence of neutron irradiation). During in-reactor tests, the mechanical response was continuously registered throughout the whole test. The results are first presented in the form of hysteresis loops confirming that the nature of deformation during these tests was truly cyclic. The temporal evolution of the stress response in the specimens is presented in the form of the average maximum stress amplitude as a function of the number of cycles as well as a function of displacement dose accumulated during the tests. The results illustrate the nature and magnitude of cyclic hardening as well as softening as a function of the number of cycles and displacement dose. Details of the microstructure were investigated using TEM and STEM techniques. The fracture surface morphology was investigated using SEM technique. Both mechanical and microstructural results are briefly discussed. The main conclusion emerging from the limited amount of present results is that neither the irradiation nor the duration of the hold-time have any significant

  13. Development of Ion-Plasma Refractory Metallic Layers of Heat-Insulating Coatings for Cooled Turbine Rotor Blades

    Science.gov (United States)

    Budinovskii, S. A.; Muboyadzhyan, S. A.; Gayamov, A. M.; Matveev, P. V.

    2014-03-01

    Alloys ZhS32 and ZhS36 with heat-protection coatings (HPC) consisting of external ceramic layers and internal refractory metallic layers are studied. The coated alloys are tested for heat fastness and high-temperature strength at 1100 - 1150°C. The HPC with a metallic layer of the (Ni - Cr - Al - Hf) + Al system are shown to be more advantageous than similar HPC based on an SPD-2 + VSDP-16 commercial refractory coating. The effect of the HPC on the characteristics of high-temperature strength and fatigue resistance of alloys ZhS32 and ZhS36 is investigated.

  14. Fracture and fatigue properties of Mo-Mo{sub 3}Si-Mo{sub 5}SiB{sub 2} refractory intermetallic alloys at ambient to elevated temperatures (25-1300 degrees Centigrade)

    Energy Technology Data Exchange (ETDEWEB)

    Choe, Heeman; Schneibel, J.H.; Ritchie, R.O.

    2002-08-01

    The need for structural materials with high-temperature strength and oxidation resistance coupled with adequate lower-temperature toughness for potential use at temperatures above {approx} 1000 degrees C has remained a persistent challenge in materials science. In this work, one promising class of intermetallic alloys is examined, namely boron-containing molybdenum silicides, with compositions in the range Mo (bal), 12-17 at. percentSi, 8.5 at. percentB, processed using both ingot (I/M) and powder (P/M) metallurgy methods. Specifically, the oxidation (''pesting''), fracture toughness and fatigue-crack propagation resistance of four such alloys, which consisted of {approx}21 to 38 vol. percent a-Mo phase in an intermetallic matrix of Mo3Si and Mo5SiB2 (T2), were characterized at temperatures between 25 degrees and 1300 degrees C. The boron additions were found to confer superior ''pest'' resistance (at 400 degrees to 900 degrees C) as compared to unmodified molybdenum silicides, such as Mo5Si3. Moreover , although the fracture and fatigue properties of the finer-scale P/M alloys were only marginally better than those of MoSi2, for the I/M processed microstructures with coarse distributions of the a-Mo phase, fracture toughness properties were far superior, rising from values above 7 MPa sqrt m at ambient temperatures to almost 12 MPa sqrt m at 1300 degrees C.

  15. Monitoring of Refractory wall recession using radar technique

    Energy Technology Data Exchange (ETDEWEB)

    University of missouri

    2003-12-30

    Furnaces are the most crucial components in the glass and metallurgical industry. Like any other components in an industry, furnaces require periodic maintenance and repair. Today, furnaces are being operated at higher temperatures and for longer periods of time thus increasing the rate of wear and tear on the furnace refractory lining. As a result of the competitive market facing these industries, longer furnace lifetime with shorter maintenance downtime are increasingly required. Higher fuel consumption, low production and safety are issues that accompany delayed maintenance. Consequently, there is a need to know the state of a refractory wall to prevent premature or unnecessary maintenance shutdowns. For many years the observation skills of an experienced operator has been the primary source of evaluating the wear associated with a refractory wall. The rate of regression of a refractory lining depends on the type of the refractory lining, the materials Monitoring of Refractory Wall Recession Using Frequency-Modulated Continuous-Wave (FM-CW) Radar Techniques: A Proof-of-Concept Study, Final Report, Submitted to the Department of Energy (DOE), September 2003. being melted, seepage, mechanical stresses, and temperature. Moreover, the regression of a refractory lining is also not uniform throughout a furnace and it is more prominent at the metal line along the sidewalls as this region is exposed to hot gaseous byproducts and flowing molten material. Hence, more accurate measurement techniques are required to determine the local residual thickness of a refractory lining so as to utilize the refractory lining to the maximum extent possible. The use of isotope radiators, thermocouples and endoscopes has also been investigated for monitoring regression. These techniques are capable of providing scanned thermal images showing the profile of the refractory wall. However, these techniques can only provide relative profile information and cannot provide absolute thickness

  16. High-Strength Aluminum Casting Alloy for High-Temperature Applications (MSFC Center Director's Discretionary Fund Final Project No. 97-10)

    Science.gov (United States)

    Lee, J. A.

    1998-01-01

    A new aluminum-silicon alloy has been successfully developed at Marshall Space Flight Center that has a significant improvement in tensile strength at elevated temperatures (550 to 700 F). For instance, the new alloy shows in average tensile strength of at least 90 percent higher than the current 390 aluminum piston alloy tested at 500 F. Compared to conventional aluminum alloys, automotive engines using the new piston alloy will have improved gas mileage, and may produce less air pollution in order to meet the future U.S. automotive legislative requirements for low hydrocarbon emissions. The projected cost for this alloy is less than $0.95/lb, and it readily allows the automotive components to be cast at a high production volume with a low, fully accounted cost. It is economically produced by pouring molten metal directly into conventional permanent steel molds or die casting.

  17. Refractories Utilizability for Slagging Gasifiers

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Slagging coal gasification process became a highlight of coal chemical industry in China during the last decade. Refractory lining's life of slagging gasifiers is one of the most critical factors for a cost -effective operation. The paper introduces current status of coal gasification in China, lining structure of slagging gasifiers and performance of refractory lining. It also summarizes the major factors impacting on refractory wear in slagging coal gasifiers in four Chinese chemical plants, based on ten years of industrial experience. The utilizability is discussed in terms of cost -effectiveness of high chromia refractories and possibility of the alternatives.

  18. Creep Resistant Zinc Alloy

    Energy Technology Data Exchange (ETDEWEB)

    Frank E. Goodwin

    2002-12-31

    This report covers the development of Hot Chamber Die Castable Zinc Alloys with High Creep Strengths. This project commenced in 2000, with the primary objective of developing a hot chamber zinc die-casting alloy, capable of satisfactory service at 140 C. The core objectives of the development program were to: (1) fill in missing alloy data areas and develop a more complete empirical model of the influence of alloy composition on creep strength and other selected properties, and (2) based on the results from this model, examine promising alloy composition areas, for further development and for meeting the property combination targets, with the view to designing an optimized alloy composition. The target properties identified by ILZRO for an improved creep resistant zinc die-casting alloy were identified as follows: (1) temperature capability of 1470 C; (2) creep stress of 31 MPa (4500 psi); (3) exposure time of 1000 hours; and (4) maximum creep elongation under these conditions of 1%. The project was broadly divided into three tasks: (1) Task 1--General and Modeling, covering Experimental design of a first batch of alloys, alloy preparation and characterization. (2) Task 2--Refinement and Optimization, covering Experimental design of a second batch of alloys. (3) Task 3--Creep Testing and Technology transfer, covering the finalization of testing and the transfer of technology to the Zinc industry should have at least one improved alloy result from this work.

  19. Creep Resistant Zinc Alloy

    Energy Technology Data Exchange (ETDEWEB)

    Frank E. Goodwin

    2002-12-31

    This report covers the development of Hot Chamber Die Castable Zinc Alloys with High Creep Strengths. This project commenced in 2000, with the primary objective of developing a hot chamber zinc die-casting alloy, capable of satisfactory service at 140 C. The core objectives of the development program were to: (1) fill in missing alloy data areas and develop a more complete empirical model of the influence of alloy composition on creep strength and other selected properties, and (2) based on the results from this model, examine promising alloy composition areas, for further development and for meeting the property combination targets, with the view to designing an optimized alloy composition. The target properties identified by ILZRO for an improved creep resistant zinc die-casting alloy were identified as follows: (1) temperature capability of 1470 C; (2) creep stress of 31 MPa (4500 psi); (3) exposure time of 1000 hours; and (4) maximum creep elongation under these conditions of 1%. The project was broadly divided into three tasks: (1) Task 1--General and Modeling, covering Experimental design of a first batch of alloys, alloy preparation and characterization. (2) Task 2--Refinement and Optimization, covering Experimental design of a second batch of alloys. (3) Task 3--Creep Testing and Technology transfer, covering the finalization of testing and the transfer of technology to the Zinc industry should have at least one improved alloy result from this work.

  20. Orind Refractories Limited

    Institute of Scientific and Technical Information of China (English)

    Mr R. Mishra; Group Manging Director

    2005-01-01

    @@ "Sight can be acquired, Vision cannot". Orind Refractories Limited (ORIND), China was formed with this rare vision. At a time when the world was testing the tepid waters of China; Mr. Ravin Jhunjhunwala, Chairman of ORIND and the management of ORIND India had looked over the Great Wall to begin a journey of success. Incorported on 18th August 1994 with an initial investment of USD 5 million, ORL caters to the ever-demanding needs of the steel industry and beyond. Incidentally ORIND was the first wholly owned India company to set up base in China. Pesently, ORIND China has a 616 strong work force including 23 expatriates.

  1. Refractoriness in human atria

    DEFF Research Database (Denmark)

    Skibsbye, Lasse; Jespersen, Thomas; Christ, Torsten

    2016-01-01

    drugs. Cardiomyocyte excitability depends on availability of sodium channels, which involves both time- and voltage-dependent recovery from inactivation. This study therefore aims to characterise how sodium channel inactivation affects refractoriness in human atria. METHODS AND RESULTS: Steady......-state activation and inactivation parameters of sodium channels measured in vitro in isolated human atrial cardiomyocytes were used to parameterise a mathematical human atrial cell model. Action potential data were acquired from human atrial trabeculae of patients in either sinus rhythm or chronic atrial...... in pharmacological management of chronic atrial fibrillation....

  2. Processing, physical metallurgy and creep of NiAl + Ta and NiAl + Nb alloys. Ph.D. Thesis. Final Contractor Report

    Science.gov (United States)

    Pathare, Viren M.

    1988-01-01

    Powder processed NiAl + Ta alloys containing 1, 2, and 4.5 at percent tantalum and NiAl + Nb alloys containing 1 and 2 at percent niobium were developed for improved creep properties. In addition, a cast alloy with 5 at percent tantalum was also studied. Hot extrusion parameters for processing alloys with 1 and 2 at percent of tantalum or niobium were designed. The NiAl + 4.5 at percent Ta alloy could be vacuum hot pressed successfully, even though it could not be extruded. All the phases in the multiphase alloys were identified and the phase transformations studied. The Ni2AlTa in NiAl + 4.5 at percent Ta alloy transforms into a liquid phase above 1700 K. Solutionizing and annealing below this temperature gives rise to a uniform distribution of fine second phase precipitates. Compressive creep properties were evaluated at 1300 K using constant load and constant velocity tests. In the higher strain rate region single phase NiAl + 1 at percent Ta and NiAl + 1 at percent Nb alloys exhibit a stress exponent of 5 characteristic of climb controlled dislocation creep. In slower strain rate regime diffusional creep becomes important. The two phase alloys containing 2 to 5 at percent Ta and 2 at percent Nb show considerable improvement over binary NiAl and single phase alloys. Loose dislocation networks and tangles stabilized by the precipitates were found in the as crept microstructure. The cast alloy which has larger grains and a distribution of fine precipitates shows the maximum improvement over binary NiAl.

  3. Development of Refractories for Continuous Casting

    Institute of Scientific and Technical Information of China (English)

    TIAN Shouxin; JIN Congjin; YAO Jinfu; LI Zeya

    2004-01-01

    The paper introduces refractories for continuous casting, especially, refractories for continuous casting for clean steel in baosteel. Developing direction of refractories for continuous casting has been pointed out to satisfy the new metallurgical operating practice.

  4. Development of a Refractory High Entropy Superalloy

    Directory of Open Access Journals (Sweden)

    Oleg N. Senkov

    2016-03-01

    Full Text Available Microstructure, phase composition and mechanical properties of a refractory high entropy superalloy, AlMo0.5NbTa0.5TiZr, are reported in this work. The alloy consists of a nano-scale mixture of two phases produced by the decomposition from a high temperature body-centered cubic (BCC phase. The first phase is present in the form of cuboidal-shaped nano-precipitates aligned in rows along <100>-type directions, has a disordered BCC crystal structure with the lattice parameter a1 = 326.9 ± 0.5 pm and is rich in Mo, Nb and Ta. The second phase is present in the form of channels between the cuboidal nano-precipitates, has an ordered B2 crystal structure with the lattice parameter a2 = 330.4 ± 0.5 pm and is rich in Al, Ti and Zr. Both phases are coherent and have the same crystallographic orientation within the former grains. The formation of this modulated nano-phase structure is discussed in the framework of nucleation-and-growth and spinodal decomposition mechanisms. The yield strength of this refractory high entropy superalloy is superior to the yield strength of Ni-based superalloys in the temperature range of 20 °C to 1200 °C.

  5. Approaches to refractory epilepsy

    Directory of Open Access Journals (Sweden)

    Jerome Engel

    2014-01-01

    Full Text Available Epilepsy is one of the most common serious neurological conditions, and 30 to 40% of people with epilepsy have seizures that are not controlled by medication. Patients are considered to have refractory epilepsy if disabling seizures continue despite appropriate trials of two antiseizure drugs, either alone or in combination. At this point, patients should be referred to multidisciplinary epilepsy centers that perform specialized diagnostic testing to first determine whether they are, in fact, pharmacoresistant, and then, if so, offer alternative treatments. Apparent pharmacoresistance can result from a variety of situations, including noncompliance, seizures that are not epileptic, misdiagnosis of the seizure type or epilepsy syndrome, inappropriate use of medication, and lifestyle issues. For patients who are pharmacoresistant, surgical treatment offers the best opportunity for complete freedom from seizures. Surgically remediable epilepsy syndromes have been identified, but patients with more complicated epilepsy can also benefit from surgical treatment and require more specialized evaluation, including intracranial EEG monitoring. For patients who are not surgical candidates, or who are unwilling to consider surgery, a variety of other alternative treatments can be considered, including peripheral or central neurostimulation, ketogenic diet, and complementary and alternative approaches. When such alternative treatments are not appropriate or effective, quality of life can still be greatly improved by the psychological and social support services offered by multidisciplinary epilepsy centers. A major obstacle remains the fact that only a small proportion of patients with refractory epilepsy are referred for expert evaluation and treatment.

  6. Refractory Celiac Disease

    Directory of Open Access Journals (Sweden)

    K Khatami

    2014-04-01

    Full Text Available Refractory celiac disease (RCD is when malabsorption symptoms and villous atrophy persist despite strict adherence to a gluten free diet (GFD for more than 12 months and other causes of villous atrophy have been ruled out.  RCD is considered a rare disease and almost exclusively occurs in adults. Persistent diarrhea, abdominal pain, weight loss are the most common symptoms in RCD. Also, anemia, fatigue, malaise, thromboembolic events and coexisting autoimmune disorders are frequent. Diagnosis of RCD is based on other causes of unresponsiveness to the GFD, particularly collagenous sprue, ulcerative jejunitis, and enteropathy-associated T-cell lymphoma. Many disorders such as autoimmune enteropathy, tropical sprue, common variable immunodeficiency, and intolerance to non-gluten dietary proteins may have similar histological findings but not necessarily identical with CD and therefore should be excluded. Repeat intestinal biopsy may help to differentiate causes of non-responsive CD associated with ongoing villous atrophy (e.g., gluten contamination, small-bowel bacterial overgrowth, RCD. There are 2 subtypes of RCD according to absence (type I or presence (type II of an abnormal intraepithelial lymphocyte population. RCD type 1 usually becomes better with a combination of aggressive nutritional support, adherence to GFD, and pharmacologic therapies such as prednisone, budesonide and azathioprine. For RCD type 2, more aggressive therapeutic approach is needed since clinical response to therapies is less certain and may evolve into aggressive enteropathy associated T-cell lymphoma and the prognosis is poor.   Key words: Celiac Disease, Refractory.  

  7. IMPROVED CORROSION RESISTANCE OF ALUMINA REFRACTORIES

    Energy Technology Data Exchange (ETDEWEB)

    John P. Hurley; Patty L. Kleven

    2001-09-30

    The initial objective of this project was to do a literature search to define the problems of refractory selection in the metals and glass industries. The problems fall into three categories: Economic--What do the major problems cost the industries financially? Operational--How do the major problems affect production efficiency and impact the environment? and Scientific--What are the chemical and physical mechanisms that cause the problems to occur? This report presents a summary of these problems. It was used to determine the areas in which the EERC can provide the most assistance through bench-scale and laboratory testing. The final objective of this project was to design and build a bench-scale high-temperature controlled atmosphere dynamic corrosion application furnace (CADCAF). The furnace will be used to evaluate refractory test samples in the presence of flowing corrodents for extended periods, to temperatures of 1600 C under controlled atmospheres. Corrodents will include molten slag, steel, and glass. This test should prove useful for the glass and steel industries when faced with the decision of choosing the best refractory for flowing corrodent conditions.

  8. Microstructural evolution and final properties of a cold-swaged multifunctional Ti–Nb–Ta–Zr–O alloy produced by a powder metallurgy route

    Energy Technology Data Exchange (ETDEWEB)

    Guo, W., E-mail: wei.guo@unsw.edu.au [School of Materials Science and Engineering, University of New South Wales, Sydney, NSW 2052 (Australia); Australian Research Council Centre of Excellence for Design in Light Metals (Australia); Quadir, M.Z., E-mail: mzquadir@unsw.edu.au [School of Materials Science and Engineering, University of New South Wales, Sydney, NSW 2052 (Australia); Australian Research Council Centre of Excellence for Design in Light Metals (Australia); Electron Microscope Unit, University of New South Wales, NSW 2052 (Australia); Moricca, S., E-mail: sam.moricca@ansto.gov.au [Institute of Materials Engineering, Australian Nuclear Science and Technology Organization (ANSTO), NSW 2232 (Australia); Eddows, T., E-mail: tex@ansto.gov.au [Institute of Materials Engineering, Australian Nuclear Science and Technology Organization (ANSTO), NSW 2232 (Australia); Ferry, M., E-mail: m.ferry@unsw.edu.au [School of Materials Science and Engineering, University of New South Wales, Sydney, NSW 2052 (Australia); Australian Research Council Centre of Excellence for Design in Light Metals (Australia)

    2013-07-15

    Body centred cubic (BCC) β-phase multifunctional titanium alloys have been developed with a very unique combination of thermal and mechanical properties. In this investigation, a very low porosity Ti–36.8–Nb–2.7Zr–2.0Ta–0.44O (wt%) alloy was produced by powder sintering, hot forging, solution treatment and cold swaging. X-ray diffraction and transmission electron microscopy (TEM) of the solution treated alloy revealed the presence of a small amount of ω-phase in a predominantly BCC β-phase matrix. Electron backscatter diffraction (EBSD) of the swaged alloy revealed a highly elongated and fragmented microstructure, and a strong 〈110〉 fibre texture. TEM also revealed the existence of stress-induced twin lamella, dislocations and ω-phase. Consistent with previous studies on these types of alloys, the swaged alloy exhibited non-linear elasticity during tensile straining, low elastic modulus (45.4 GPa), high elastic limit (2.3%), high elongation to failure (8.1%), and a high yield strength (880 MPa) and tensile strength (940 MPa). The coefficient of thermal expansion was also low (∼5×10{sup −6} K{sup −1} between 50 and 300 °C) in this alloy.

  9. Aluminum-Scandium Alloys: Material Characterization, Friction Stir Welding, and Compatibility With Hydrogen Peroxide (MSFC Center Director's Discretionary Fund Final Report, Proj. No. 04-14)

    Science.gov (United States)

    Lee, J. A.; Chen, P. S.

    2004-01-01

    This Technical Memorandum describes the development of several high-strength aluminum (Al) alloys that are compatible with hydrogen peroxide (H2O2) propellant for NASA Hypersonic-X (Hyper-X) vehicles fuel tanks and structures. The yield strengths for some of these Al-magnesium-based alloys are more than 3 times stronger than the conventional 5254-H112 Al alloy, while maintaining excellent H2O2 compatibility similar to class 1 5254 alloy. The alloy development strategy is to add scandium, zirconium, and other transitional metals with unique electrochemical properties, which will not act as catalysts, to decompose the highly concentrated 90 percent H2O2. Test coupons are machined from sheet metals for H2O2 long-term exposure testing and mechanical properties testing. In addition, the ability to weld the new alloys using friction stir welding has also been explored. The new high-strength alloys could represent an enabling material technology for Hyper-X vehicles, where flight weight reduction is a critical requirement.

  10. Refractory chronic migraine

    DEFF Research Database (Denmark)

    Martelletti, Paolo; Katsarava, Zaza; Lampl, Christian

    2014-01-01

    and in the uncontrolled application of therapeutic techniques not yet validated.The European Headache Federation Expert Group on rCM presents hereby the updated definition criteria for this harmful subset of headache disorders. This attempt wants to be the first impulse towards the correct identification......The debate on the clinical definition of refractory Chronic Migraine (rCM) is still far to be concluded. The importance to create a clinical framing of these rCM patients resides in the complete disability they show, in the high risk of serious adverse events from acute and preventative drugs...... of these patients, the correct application of innovative therapeutic techniques and lastly aim to be acknowledged as clinical entity in the next definitive version of the International Classification of Headache Disorders 3 (ICHD-3 beta)....

  11. Refractory status epilepticus.

    Science.gov (United States)

    Fernandez, Andres; Claassen, Jan

    2012-04-01

    Refractory status epilepticus (RSE) has a high morbidity and mortality. There are currently no definitive data to guide both the optimal choice of therapy and treatment goals. This review focuses on RSE diagnosis and outcome and discusses both commonly used and anecdotal therapies for RSE. The challenges in performing randomized controlled trials (RCTs) in neurocritical care and more specifically for the treatment of RSE are illustrated by the early termination of the first RCT of RSE due to low recruitment that compared propofol to barbiturates. Recent case series include the successful treatment of recurrent RSE with ketamine, intravenous lacosamide as an add-on treatment, the use of combination antiepileptics (phenytoin, levetiracetam, and pregabalin), and surgical treatments (vagal nerve and deep brain stimulation) for the control of RSE. A number of different therapeutic options are available for the treatment of RSE but none have been shown to be superior to others at this point.

  12. Preparation of Permanent Mold Coating Using Magnesia Powder for Magnesium Alloys

    Science.gov (United States)

    Guo, Guangsi; Wang, Guangtai; Yu, Haifeng; Ye, Sheng

    A kind of permanent mold coating for magnesium alloy was developed using magnesia powder and diatomite as refractory aggregate. The properties of the coating were tested and analyzed by various ingredients. The final ingredient was determined through the tests which are to find out the optimal proportion of two kinds of aggregate and the influences to coating properties by changing the proportion of binder and suspending agents. The experimental results shown that the permanent mold coating performed good properties on magnesium alloys when the optimized ratio of magnesia powder and diatomite was 6: 4, and the integrated property is very excellent when the coating was prepared with 2 percent of sodium bentonite, 0.4 percent of CMC, 7 percent of sodium hexametaphosphate, and 7 percent of sodium silicate. The excellent performance has also been proved by actual casting test.

  13. Sample Preparation for Monolithic Refractories Part 1: Refractory Castables

    Institute of Scientific and Technical Information of China (English)

    Zhang Xiaohui; Peng Xigao

    2010-01-01

    @@ 1 Scope This standard specifies the definition and test methods of flowability of dense and insulating refractory castables,and moulding equipment,moulding methods,curing and drying conditions of castables samples.

  14. Evaluation of a diffusion/trapping model for hydrogen ingress in high-strength alloys. Final technical report, November 1988-November 1990

    Energy Technology Data Exchange (ETDEWEB)

    Pound, B.G.

    1990-11-14

    The objective of this research was to obtain the hydrogen ingress and trapping characteristics for a range of microstructures and so identify the dominant type of irreversible trap in different alloys. A diffusion/trapping model was used in conjunction with a potentiostatic pulse technique to study the ingress of hydrogen in three precipitation-hardened alloys (Inconel 718, Incoloy 925, and 18Ni maraging steel), two work-hardened alloys (Inconel 625 and Hastelloy C-276), titanium (pure and grade 2), and copper-enriched AISI 4340 steel in 1 mol/L acetic acid-1 mol/L sodium acetate containing 15 ppm arsenic oxide. In all cases except pure titanium, the data were shown to fit the interface-control form of the model and values were determined for the irreversible trapping constants (k) and the flux of hydrogen into the alloys. The density of irreversible trap defects were calculated from k and generally found to be in close agreement with the concentration of a specific heterogeneity in each alloy. Moreover, the trapping constants for the alloys were found to be consistent with their relative susceptibilities to hydrogen embrittlement.

  15. Present Situation of Refractories for Baosteel

    Institute of Scientific and Technical Information of China (English)

    TAI Li; SHEN Keyin

    2004-01-01

    The paper reviews the present situation of refractories for Baosteel, including refractories for iron-making system, converters, ladles and tundishes. Descriptions have been also conducted on the environment protection and reutilization of refractories in Baosteel, together with somesuggestions for refractories suppliers to meet the advancement in iron and steel making technology of Baosteel.

  16. Design, engineering, and evaluation of refractory liners for slagging gasifiers. Second annual technical progress report, 1 October 1979-30 September 1980

    Energy Technology Data Exchange (ETDEWEB)

    Booth, G.; Firestone, R. F.; Greaves, M. J.; Hales, C.; Lamoureux, J. P.; Ledford, R. R.

    1980-10-01

    The program has been making steady progress to completion. The refractory liner test system is a much more complex design than originally proposed, but it is also safer and better able to simulate the actual coal gasification environment to which refractories will be exposed. Consequently, the data from the tests will be more reliable and the final handbook more useful for refractory liner design.

  17. Design, engineering, and evaluation of refractory liners for slagging gasifiers. Second annual technical progress report, 1 October 1979-30 September 1980

    Energy Technology Data Exchange (ETDEWEB)

    Booth, G.; Firestone, R. F.; Greaves, M. J.; Hales, C.; Lamoureux, J. P.; Ledford, R. R.

    1980-10-01

    The program has been making steady progress to completion. The refractory liner test system is a much more complex design than originally proposed, but it is also safer and better able to simulate the actual coal gasification environment to which refractories will be exposed. Consequently, the data from the tests will be more reliable and the final handbook more useful for refractory liner design.

  18. Self-flow Refractory Castables

    Institute of Scientific and Technical Information of China (English)

    Zhang Xiaohui; Peng Xigao

    2010-01-01

    @@ 1 Scope This standard specifies the term and definition,classification, technical requirements, test methods,quality appraisal procedures, packing, marking, transportation, storage, and quality certificate of self-flow refractory castables.

  19. Alumina-magnesia Refractory Castables

    Institute of Scientific and Technical Information of China (English)

    Wang Jing

    2010-01-01

    @@ 1 Scope This standard specifies the classification,technical requirements,test methods,quality appraisal procedures,packing,marking,transportation,storage,and quality certificate of alumina-magnesia refractory castables.

  20. Upfront lower dose lenalidomide is less toxic and does not compromise efficacy for vulnerable patients with relapsed refractory multiple myeloma: final analysis of the phase II RevLite study.

    Science.gov (United States)

    Quach, Hang; Fernyhough, Liam; Henderson, Ross; Corbett, Gillian; Baker, Bart; Browett, Peter; Blacklock, Hilary; Forsyth, Cecily; Underhill, Craig; Cannell, Paul; Trotman, Judith; Neylon, Annette; Harrison, Simon; Link, Emma; Swern, Arlene; Cowan, Linda; Dimopoulos, Meletios A; Miles Prince, H

    2017-02-15

    The combination of lenalidomide and dexamethasone is an established treatment for patients with multiple myeloma (MM). Increasingly, treatment attenuation is advocated for frail/elderly patients to minimize toxicity even though there have been no prospective studies to demonstrate whether lenalidomide dose attenuation impacts on response and survival outcome. This prospective multicentre phase II study assessed the efficacy and tolerability of lower dose lenalidomide (15 mg) and dexamethasone (20 mg) in 149 eligible patients with relapsed/refractory MM aged over 59 years and/or with renal impairment. The overall response rate was 71% (complete response 15%). Median (range) progression-free survival (PFS) and overall survival (OS) were 8·9 (6·9-11·5) and 30·5 (20·0-36·2) months, respectively. Upon formal statistical comparison of these endpoints to that of a matched cohort of patients from the pivotal phase III MM009/MM010 studies who received standard-dose lenalidomide (25 mg) and high-dose dexamethasone (40 mg) no difference was seen in PFS (P = 0·34) and OS (P = 0·21). Importantly, grade 3-4 toxicities were reduced with low-dose lenalidomide, mainly lower neutropenia (29% vs. 41%), infections (23% vs. 31%) and venous thromboembolism (3% vs. 13%). This study supports a strategy of lenalidomide dose reduction at the outset for at-risk patients, and prospectively confirms that such an approach reduces adverse events while not compromising patient response or survival outcomes.

  1. Impact of alternate fuels on industrial refractories and refractory insulation applications. An Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Wei, G.C.; Tennery, V.J.

    1976-09-01

    The effects of use of alternate fuels such as distillate oils, residual oils, coal, producer gas, and electricity on refractory insulation are evaluated. Sections are included on alternate fuels for 1976 to 1980, assessment by industry of fuel conversion impact on industrial refractories in the period 1976 to 1980, interactions of alternate fuel combustion products with refractories and refractory insulation, and analysis of degradation mechanisms in refractories and refractory materials. (JRD)

  2. Strengthening mechanisms, creep, and fatigue processes in dispersion-hardened niobium alloy. Final scientific report, 1 Feb 89-31 Jan 92

    Energy Technology Data Exchange (ETDEWEB)

    Mukherjee, A.K.; Gibeling, J.C.

    1992-04-20

    The creep and fatigue properties of pure Nb and Nb-l%Zr alloy were investigated. A model was developed based on the migration of subgrain boundary that can explain the anomalous primary creep transients found in Nb-l%Zr alloy, due to coarsening of subgrain structure. TEM investigations confirmed that such subgrain coarsening occurs during primary creep of Nb-l%Zr. Baseline low cycle fatigue studies of Nb and Nb-l%Zr were completed. Cyclic hardening is observed and there is a microplastic plateau in Nb. The Nb-1%Zr is stronger in cyclic deformation than Nb, with little influence of strain rate. The deformation in the alloy at both high and low strain rates is controlled by the interaction between gliding edge dislocation and solute atoms.

  3. Development of a Refractory High Entropy Superalloy (Postprint)

    Science.gov (United States)

    2016-03-17

    primary phase . RHEAs with a low density and high strength are among the most promising recent achievements in this field [19–23]. In particular, the...after annealing at 1400 °C for 24 h. Second- phase precipitates (which are dark) are present at grain boundaries. (a) (b) Figure 4. High magnification...Microstructure, phase composition and mechanical properties of a refractory high entropy super alloy, AlMo0.5NbTa0.5TiZr, are reported in this work. The

  4. TUNGSTEN BASE ALLOYS

    Science.gov (United States)

    Schell, D.H.; Sheinberg, H.

    1959-12-15

    A high-density quaternary tungsten-base alloy having high mechanical strength and good machinability composed of about 2 wt.% Ni, 3 wt.% Cu, 5 wt.% Pb, and 90wt.% W is described. This alloy can be formed by the powder metallurgy technique of hot pressing in a graphite die without causing a reaction between charge and the die and without formation of a carbide case on the final compact, thereby enabling re-use of the graphite die. The alloy is formable at hot- pressing temperatures of from about 1200 to about 1350 deg C. In addition, there is little component shrinkage, thereby eliminating the necessity of subsequent extensive surface machining.

  5. Carbide Coatings for Nickel Alloys, Graphite and Carbon/Carbon Composites to be used in Fluoride Salt Valves

    Energy Technology Data Exchange (ETDEWEB)

    Nagle, Denis [Johns Hopkins Univ., Baltimore, MD (United States); Zhang, Dajie [Johns Hopkins Univ., Baltimore, MD (United States)

    2015-10-22

    The focus of this research was concerned with developing materials technology that supports the evolution of Generation IV Advanced High Temperature Reactor (AHTR) concepts. Specifically, we investigate refractory carbide coatings for 1) nickel alloys, and 2) commercial carbon-carbon composites (CCCs). Numerous compelling reasons have driven us to focus on carbon and carbide materials. First, unlike metals, the strength and modulus of CCCs increase with rising temperature. Secondly, graphite and carbon composites have been proven effective for resisting highly corrosive fluoride melts such as molten cryolite [Na₃AlF₆] at ~1000°C in aluminum reduction cells. Thirdly, graphite and carbide materials exhibit extraordinary radiation damage tolerance and stability up to 2000°C. Finally, carbides are thermodynamically more stable in liquid fluoride salt than the corresponding metals (i.e. Cr and Zr) found in nickel based alloys.

  6. Long - range foundry Al composite alloys

    Directory of Open Access Journals (Sweden)

    A. D. Mekhtiev

    2014-10-01

    Full Text Available The technology of obtaining nanostructural composite aluminum alloys consists in the plasma injection of refractory nanometric particles with simultaneous two-plane magnetic dynamic mixing of the melt. Particularly important in obtaining composite aluminum matrix alloys is the provision of the introduced particles wettability with the matrix melt for forming stable adhesive bonds. Nanostructured powder components can be considered not only to be a starting product for producing nanostructural composite aluminum alloys but as an independent commerce product. Nanostructural composite metal matrix alloys make one of the most prospective structural materials of the future, and liquid-phase technologies of their obtaining are the most competitive in producing products of nanostructural composite aluminum alloys in the industrial scale.

  7. Company Profile Dengfeng Chunsheng Refractories Co., Ltd.

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ Dengfeng Chunsheng Refractories Co., Ltd. is an industrial enterprise integrating refractories research, design, manufacturing and engineering service into one and was entitled as one of China's high-quality silica bricks production and export bases.

  8. Magnesia-Chrome Refractories for Flash Furnace

    Institute of Scientific and Technical Information of China (English)

    LI Yong; CHEN Kaixian; LU Xinghua; LIU Jianlong; SUN Jialin; HONG Yanruo

    2002-01-01

    The rapid development of our country's heavy nonferrous metallurgical technology and the revolution in new type of heavynon-ferrous metallurgical furnace have imposed more critical demand on the refractory materials ,i. e. high quality and long service life. This paper presents the domestic status of the refractories for flash furnace , briefly describes the wear of the refractory used , and it is considered that the domestic in refractories for flashfurnace can be surely realized.

  9. Reuse and Reproduction of Used Refractories

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The paper analyzed the recycle condition and developing trend of used refractories China and other countries, including research achievements of recycles of used refractories such as MgO-C bricks, Al2O3-MgO-C bricks, Al2O3-SiC-C castable and MgO-Cr2O3 bricks. Recycled refractories exhibit the same or even better properties as compared with the original. In addition, prospects for recycle of used refractories are also discusseded.

  10. Influence of the final temperature of investment healting on the tensile strength and Vickers hardness of CP Ti and Ti-6Al-4V alloy

    Directory of Open Access Journals (Sweden)

    Pedro César Garcia Oliveira

    2007-02-01

    Full Text Available The aim of the work was to evaluate the influence of the temperature of investment healting on the tensile strength and Vickers hardness of CP Ti and Ti-6Al-4V alloy casting. Were obtained for the tensile strength test dumbbell rods that were invested in the Rematitan Plus investment and casting in the Discovery machine cast. Thirty specimens were obtained, fiftten to the CP Titanium and fifteen to the Ti-6Al-4V alloy, five samples to each an of the three temperatures of investment: 430ºC (control group, 480ºC and 530ºC. The tensile test was measured by means of a universal testing machine, MTS model 810, at a strain of 1.0 mm/min. After the tensile strenght test the specimens were secctioned, embedded and polished to hardness measurements, using a Vickers tester, Micromet 2100. The means values to tensile tests to the temperatures 430ºC, 480 and 530: CP Ti (486.1 - 501.16 - 498.14 -mean 495.30 MPa and Ti-6Al-4V alloy (961.33 - 958.26 - 1005.80 - mean 975.13 MPa while for the Vickers hardness the values were (198.06, 197.85, 202.58 - mean 199.50 and (352.95, 339.36, 344.76 - mean 345.69, respectively. The values were submitted to Analysis of Variance (ANOVA and Tukey,s Test that indicate differences significant only between the materials, but not between the temperature, for both the materias. It was conclued that increase of the temperature of investment its not chance the tensile strength and the Vickers hardness of the CP Titanium and Ti-6Al-4V alloy.

  11. Influence of cooling after homogenisation and reheating to extrusion on extrudability and final properties of AA 6063 and AA6082 alloys

    Energy Technology Data Exchange (ETDEWEB)

    Zajac, S. [Swedish Inst. for Metals Research, Stockholm (Sweden); Bengtsson, B. [Sapa Technology, Finspang (Sweden); Joensson, C. [Sapa AB, Finspang (Sweden)

    2002-07-01

    The influence of cooling conditions after homogenisation and preheating conditions to extrusion temperature have been investigated on AA 6063 and AA 6082 aluminium alloys with regard to the Mg{sub 2}Si particle development and their effect on flow stress at the extrusion temperature and hot ductility as well as hardness after ageing. Both continuous and isothermal cooling (step-cooling) were investigated in combination with fast induction heating and slow gas heating of the billet prior to extrusion. (orig.)

  12. Final report on characterization of physical and mechanical properties of copper and copper alloys before and after irradiation. (ITER R and D Task no. T213)

    Energy Technology Data Exchange (ETDEWEB)

    Singh, B.N.; Taehtinen, S. [VTT Manufacturing Technology (Finland)

    2001-12-01

    The present report summarizes and highlights the main results of the work carried out during the last 5 - 6 years on effects of neutron irradiation on physical and mechanical properties of copper and copper alloys. The work was an European contribution to ITER Research and Development programme and was carried out by the Associations Euratom - Risoe and Euratom - Tekes. Details of the investigations carried out within the framework of the present task and the main results have been reported in various reports and journal publication. On the basis of these results some conclusions are drawn regarding the suitability of a copper alloy for its use in the first wall and divertor components of ITER. It is pointed out that the present work has managed only to identify some of the critical problems and limitations of the copper alloys for their employment in the hostile environment of 14 MeV neutrons. A considerable amount of further effort is needed to find a realistic and optimum solution. (au)

  13. High-temperature alloys for high-power thermionic systems

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Kwang S.; Jacobson, D.L.; D' cruz, L.; Luo, Anhua; Chen, Bor-Ling.

    1990-08-01

    The need for structural materials with useful strength above 1600 k has stimulated interest in refractory-metal alloys. Tungsten possesses an extreme high modulus of elasticity as well as the highest melting temperature among metals, and hence is being considered as one of the most promising candidate materials for high temperature structural applications such as space nuclear power systems. This report is divided into three chapters covering the following: (1) the processing of tungsten base alloys; (2) the tensile properties of tungsten base alloys; and (3) creep behavior of tungsten base alloys. Separate abstracts were prepared for each chapter. (SC)

  14. Management of chronic refractory cough.

    Science.gov (United States)

    Gibson, Peter G; Vertigan, Anne E

    2015-12-14

    Chronic refractory cough (CRC) is defined as a cough that persists despite guideline based treatment. It is seen in 20-46% of patients presenting to specialist cough clinics and it has a substantial impact on quality of life and healthcare utilization. Several terms have been used to describe this condition, including the recently introduced term cough hypersensitivity syndrome. Key symptoms include a dry irritated cough localized around the laryngeal region. Symptoms are not restricted to cough and can include globus, dyspnea, and dysphonia. Chronic refractory cough has factors in common with laryngeal hypersensitivity syndromes and chronic pain syndromes, and these similarities help to shed light on the pathophysiology of the condition. Its pathophysiology is complex and includes cough reflex sensitivity, central sensitization, peripheral sensitization, and paradoxical vocal fold movement. Chronic refractory cough often occurs after a viral infection. The diagnosis is made once the main diseases that cause chronic cough have been excluded (or treated) and cough remains refractory to medical treatment. Several treatments have been developed over the past decade. These include speech pathology interventions using techniques adapted from the treatment of hyperfunctional voice disorders, as well as the use of centrally acting neuromodulators such as gabapentin and pregabalin. Potential new treatments in development also show promise.

  15. Refractory disease in autoimmune diseases

    NARCIS (Netherlands)

    Vasconcelos, Carlos; Kallenberg, Cees; Shoenfeld, Yehuda

    2011-01-01

    Refractory disease (RD) definition has different meanings but it is dynamic, according to knowledge and the availability of new drugs. It should be differentiated from severe disease and damage definitions and it must take into account duration of adequate therapy and compliance of the patient. It c

  16. A novel Fe–Cr–Nb matrix composite containing the TiB{sub 2} neutron absorber synthesized by mechanical alloying and final hot isostatic pressing (HIP) in the Ti-tubing

    Energy Technology Data Exchange (ETDEWEB)

    Litwa, Przemysław [Department of Advanced Materials and Technologies, Military University of Technology, Kaliskiego 2, 00-908 Warsaw (Poland); Perkowski, Krzysztof [Department of Nanotechnology, Institute of Ceramics and Building Materials, Postępu 9, 02-676 Warsaw (Poland); Zasada, Dariusz [Department of Advanced Materials and Technologies, Military University of Technology, Kaliskiego 2, 00-908 Warsaw (Poland); Kobus, Izabela; Konopka, Gustaw [Department of Nanotechnology, Institute of Ceramics and Building Materials, Postępu 9, 02-676 Warsaw (Poland); Czujko, Tomasz [Department of Advanced Materials and Technologies, Military University of Technology, Kaliskiego 2, 00-908 Warsaw (Poland); Varin, Robert A., E-mail: robert.varin@uwaterloo.ca [Department of Mechanical and Mechatronics Engineering, University of Waterloo, 200 University Ave., Waterloo, ON N2L 3G1 (Canada)

    2016-07-25

    The Fe–Cr–Ti-Nb elemental powders were mechanically alloyed/ball milled with TiB{sub 2} and a small quantity of Y{sub 2}O{sub 3} ceramic to synthesize a novel Fe-based alloy-ceramic powder composite that could be processed by hot isostatic pressing (HIP) for a perceived potential application as a neutron absorber in nuclear reactors. After ball milling for the 30–80 h duration relatively uniform powders with micrometric sizes were produced. With increasing milling time a fraction of TiB{sub 2} particles became covered with the much softer Fe-based alloy which resulted in the formation of a characteristic “core-mantel” structure. For the final HIP-ing process the mechanically alloyed powders were initially uniaxially pressed into rod-shaped compacts and then cold isostatically pressed (CIP-ed). Subsequently, the rod-shaped compacts were placed in the Ti-tubing and subjected to hot isostatic pressing (HIP) at 1150 °C/200 MPa pressure. The HIP-ing process resulted in the formation of the near-Ti and intermediate diffusional layers in the microstructure of HIP-ed samples which formed in accord with the Fe-Ti binary phase diagram. Those layers contain the phases such as α-Ti (HCP), the FeTi intermetallic and their hypo-eutectoid mixtures. In addition, needle-like particles were formed in both layers in accord with the Ti-B binary phase diagram. Nanohardness testing, using a Berkovich type diamond tip, shows that the nanohardness in the intermediate layer areas, corresponding to the composition of the hypo-eutectoid mixture of Ti-FeTi, equals 980.0 (±27.1) HV and correspondingly 1176.9 (±47.6) HV for the FeTi phase. The nanohardness in the sample's center in the areas with the fine mixture of Fe-based alloy and small TiB{sub 2} particles equals 1048.3 (±201.8) HV. The average microhardness of samples HIP-ed from powders milled for 30 and 80 h is 588 HV and 733 HV, respectively. - Highlights: • A Fe–Cr–Nb-based composite with TiB{sub 2} neutron

  17. Transient refractory material dissolution by a volumetrically-heated melt

    Energy Technology Data Exchange (ETDEWEB)

    Seiler, Jean Marie, E-mail: jean-marie.seiler@cea.fr [CEA, DEN, DTN, 17 Rue des Martyrs, 38054 Grenoble Cedex 9 (France); Ratel, Gilles [CEA, DEN, DTN, 17 Rue des Martyrs, 38054 Grenoble Cedex 9 (France); Combeau, Hervé [Institut Jean Lamour, UMR 7198, Lorraine University, Ecole des Mines de Nancy, Parc de Saurupt, 54042 Nancy Cedex (France); Gaus-Liu, Xiaoyang; Kretzschmar, Frank; Miassoedov, Alexei [Karlsruhe Institut of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

    2014-12-15

    Highlights: • We describe a test investigating ceramic dissolution by a molten non-eutectic melt. • The evolution of the interface temperature between melt and refractory is measured. • A theoretical model describing dissolution kinetics is proposed. • When dissolution stops, interface temperature is the liquidus temperature of the melt. - Abstract: The present work addresses the question of corium–ceramic interaction in a core catcher during a core-melt accident in a nuclear power plant. It provides an original insight into transient aspects concerning dissolution of refractory material by a volumetrically heated pool. An experiment with simulant material (LIVECERAM) is presented. Test results clearly show that dissolution of solid refractory material can occur in a non-eutectic melt at a temperature which is lower than the melting temperature of the refractory material. During the dissolution transient, the interface temperature rises above the liquidus temperature, corresponding to the instantaneous average composition of the melt pool. With constant power dissipation in the melt and external cooling of the core-catcher, a final steady-state situation is reached. Dissolution stops when the heat flux (delivered by the melt to the refractory) can be removed by conduction through the residual thickness of the ceramic, with T{sub interface} = T{sub liquidus} (calculated for the average composition of the final liquid pool). The final steady state corresponds to a uniform pool composition and uniform interface temperature distribution. Convection in the pool is governed by natural thermal convection and the heat flux distribution is therefore similar to what would be obtained for a single component pool. An interpretation of the experiment with two model-based approaches (0D and 1D) is presented. The mass transfer kinetics between the interface and the bulk is controlled by a diffusion sublayer within the boundary layer. During the dissolution transient

  18. ROLE OF ULTRASOUND IN MECHANISMS OF ANODE-CATHODE INTERACTIONS DURING ELECTROSPARK ALLOYING

    Directory of Open Access Journals (Sweden)

    N. M. Chigrinova

    2016-01-01

    Full Text Available The paper reveals results of investigations on mass transfer kinetics and dynamics of coating formation while using integral electrospark alloying method with additional ultrasonic exposure at different stages of formation. Nowadays, a classical method for electrospark alloying with hard-alloy anodes and impulse AC voltage frequency on the vibration exciter coil from 20 to 1600 Hz has been mainly used for application of protective and strengthening coatings within permissible thickness and characteristics. The key aspect of ultrasonic exposure application (frequency 22–44 kHz during electrospark alloying is the possibility to increase further thickness of coatings to be formed even after reaching a brittle fracture threshold of the coating material. Methodology of the executed research activity has been based on integrated studies (gravimetric, metallographic, X-ray diffraction and electron microscopic of coatings which are to be formed through compositions produced while using method of high-energy hot compaction and a “refractory carbide (WC and a binding material“ system in the form of alloy based on nickel from the series of “colmonoy” Ni – Ni3B system which is alloyed with additions of copper and silicon. The initial surface treatment within ultrasonic frequency range (22–44 kHz contributes to a noticeable increase in the mass transfer rate, which is primarily determined by chemical composition and thermodynamic stability of anodes. It is due to surface activation in the process of its preliminary deformation at ultrasonic frequency which creates additional conditions for striking of a spark.The final ultrasonic treatment improves coating quality due to its additional forging that leads to an increase of its structure homogeneity and density.

  19. Bulk Vitrification Performance Enhancement: Refractory Lining Protection Against Molten Salt Penetration

    Energy Technology Data Exchange (ETDEWEB)

    Hrma, Pavel R.; Bagaasen, Larry M.; Schweiger, Michael J.; Evans, Michael B.; Smith, Benjamin T.; Arrigoni, Benjamin M.; Kim, Dong-Sang; Rodriguez, Carmen P.; Yokuda, Satoru T.; Matyas, Josef; Buchmiller, William C.; Gallegos, Autumn B.; Fluegel, Alexander

    2007-08-06

    Bulk vitrification (BV) is a process that heats a feed material that consists of glass-forming solids and dried low-activity waste (LAW) in a disposable refractory-lined metal box using electrical power supplied through carbon electrodes. The feed is heated to the point that the LAW decomposes and combines with the solids to generate a vitreous waste form. This study supports the BV design and operations by exploring various methods aimed at reducing the quantities of soluble Tc in the castable refractory block portion of the refractory lining, which limits the effectiveness of the final waste form.

  20. REVIEW ON RESEARCH AND DEVELOPMENT OF MAGNESIUM ALLOYS

    Institute of Scientific and Technical Information of China (English)

    Z.Yaug; J.P.Li; J.X.Zhang; G.W.Lorimer; J.Robson

    2008-01-01

    The current research and development of magnesium alloys is summarized. Several aspects of magnesium alloys are described: cast Mg alloy, wrought Mg alloy, and novel processing. The subjects are discussed individually and recommendations for further study arc listed in the final section.

  1. Chromia refractory brick with carbon treatment

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, James P.; Kwong, Kyei-Sing

    2017-03-21

    The disclosure provides a refractory brick system comprising a chromia refractory brick for operation in the slagging environment of an air-cooled gasifier. The chromia refractory brick comprises a ceramically-bonded porous chromia refractory having a porosity greater than 9% and having carbon deposits residing within the pores. The brick may be further comprised of Al.sub.2O.sub.3. The air-cooled gasifier generates a liquefied slag in contact with the refractory brick and generally operates at temperatures between 1250.degree. C. and 1575.degree. C. and pressures between 300 psi to 1000 psi, with oxygen partial pressures generally between 10.sup.-4 and 10.sup.-10 atm. The refractory brick performs without substantial chromium carbide or chromium metal formation in the low oxygen partial pressure environment. The inclusion of carbon without chromium carbide formation provides for significant mitigation of slag penetration and significantly reduced refractory wear.

  2. High-Efficiency Amorphous Silicon Alloy Based Solar Cells and Modules; Final Technical Progress Report, 30 May 2002--31 May 2005

    Energy Technology Data Exchange (ETDEWEB)

    Guha, S.; Yang, J.

    2005-10-01

    The principal objective of this R&D program is to expand, enhance, and accelerate knowledge and capabilities for development of high-efficiency hydrogenated amorphous silicon (a-Si:H) and amorphous silicon-germanium alloy (a-SiGe:H) related thin-film multijunction solar cells and modules with low manufacturing cost and high reliability. Our strategy has been to use the spectrum-splitting triple-junction structure, a-Si:H/a-SiGe:H/a-SiGe:H, to improve solar cell and module efficiency, stability, and throughput of production. The methodology used to achieve the objectives included: (1) explore the highest stable efficiency using the triple-junction structure deposited using RF glow discharge at a low rate, (2) fabricate the devices at a high deposition rate for high throughput and low cost, and (3) develop an optimized recipe using the R&D batch large-area reactor to help the design and optimization of the roll-to-roll production machines. For short-term goals, we have worked on the improvement of a-Si:H and a-SiGe:H alloy solar cells. a-Si:H and a-SiGe:H are the foundation of current a-Si:H based thin-film photovoltaic technology. Any improvement in cell efficiency, throughput, and cost reduction will immediately improve operation efficiency of our manufacturing plant, allowing us to further expand our production capacity.

  3. Materials problems in fluidized-bed combustion systems. Appendix 3. Evaluation of boiler alloy specimens at Foster Wheeler Development Corporation. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Amoruso, G.V.; Apblett, A.R. Jr.

    1980-05-01

    This report summarizes the results of the Foster Wheeler Development Corporation (FWDC) portion of a metallurgical investigation conducted to assess the corrosion behavior of various ferritic, austenitic, and nickel-base alloys which were exposed in a coal-burning fluidized bed test facility at nominal temperatures of 1000/sup 0/F, 1200/sup 0/F, 1400/sup 0/F, 1550/sup 0/F, and 1650/sup 0/F for 1000 and 2000 hour test exposure periods. The alloys included Corten, 2-1/4Cr-1Mo, 9Cr-1Mo, 405 SS, E-Brite 26-1, 310 SS, 329 SS, 347 SS, 22-13-5, 21-6-9, Incoloy 800, Manaurite 36X, Inconel 690, and RA 333. The investigation included material precharacterization studies and post-test metallurgical evaluations involving deposit/scale thickness measurements, selective chemical/microprobe analyses, specimen surface recession measurements, determination of depths of dealloying and corrosive constituent penetrations, grain-size determinations, hardness surveys, macro and microscopic examinations and study/recording of microstructural changes resulting as a consequence of test exposure.

  4. Formation of Refractory Metal Alloys and Their Occurrence in CAIs

    Science.gov (United States)

    Schwander, D.; Berg, T.; Ott, U.; Schönhense, G.; Palme, H.

    2012-09-01

    At the conference we will give an overview of the current state of our research of RMN from Murchison, Allende and Acfer 094 including statistical analysis of their compositions and structures in relation to condensation calculations.

  5. Alloimmune refractoriness to platelet transfusions.

    Science.gov (United States)

    Sandler, S G

    1997-11-01

    Patients who are transfused on multiple occasions with red cells or platelets may develop platelet-reactive alloantibodies and experience decreased clinical responsiveness to platelet transfusion. This situation, conventionally described as "refractoriness to platelet transfusions," is defined by an unsatisfactory low post-transfusion platelet count increment. If antibodies to HLAs are detected, improved clinical outcomes may result from transfusions of HLA-matched or donor-recipient cross-matched platelets. Because refractoriness is an expected, frequently occurring phenomenon, prevention of HLA alloimmunization is an important management strategy. Prevention strategies include efforts to decrease the number of transfusions, filtration of cellular components to reduce the number of HLA-bearing leukocytes, or pretransfusion ultraviolet B irradiation of cellular components to decrease their immunogenicity. Other investigational approaches include reducing the expression of HLAs on transfused platelets, inducing a transient reticuloendothelial system blockade by infusions of specialized immunoglobulin products, or transfusing semisynthetic platelet substitutes (thromboerythrocytes, thrombospheres) or modified platelets (infusible platelet membranes, lyophilized platelets).

  6. Iron refractory iron deficiency anemia

    OpenAIRE

    De Falco, Luigia; Sanchez, Mayka; Silvestri, Laura; Kannengiesser, Caroline; Muckenthaler, Martina U; Iolascon, Achille; Gouya, Laurent; Camaschella, Clara; Beaumont, Carole

    2013-01-01

    Iron refractory iron deficiency anemia is a hereditary recessive anemia due to a defect in the TMPRSS6 gene encoding Matriptase-2. This protein is a transmembrane serine protease that plays an essential role in down-regulating hepcidin, the key regulator of iron homeostasis. Hallmarks of this disease are microcytic hypochromic anemia, low transferrin saturation and normal/high serum hepcidin values. The anemia appears in the post-natal period, although in some cases it is only diagnosed in ad...

  7. Understanding and treating refractory constipation

    Institute of Scientific and Technical Information of China (English)

    Gabrio; Bassotti; Corrado; Blandizzi

    2014-01-01

    Chronic constipation is a frequently encountered disorder in clinical practice. Most constipated patients benefit from standard medical approaches. However, current therapies may fail in a proportion of patients. These patients deserve better evaluation and thorough investigations before their labeling as refractory to treatment. Indeed, several cases of apparent refractoriness are actually due to misconceptions about constipation, poor basal evaluation (inability to recognize secondary causes of constipation, use of constipating drugs) or inadequate therapeutic regimens. After a careful reevaluation that takes into account the above factors, a certain percentage of patients can be defined as being actually resistant to first-line medical treatments. These subjects should firstly undergo specific diagnostic examination to ascertain the subtype of constipation. The subsequent therapeutic approach should be then tailored according to their underlying dysfunction. Slow transit patients could benefit from a more robust medical treatment, based on stimulant laxatives (or their combination with osmotic laxatives, particularly over the short-term), enterokinetics (such as prucalopride) or secretagogues (such as lubiprostone or linaclotide). Patients complaining of obstructed defecation are less likely to show a response to medical treatment and might benefit from biofeedback, when available. When all medical treatments prove to be unsatisfactory, other approaches may be attempted in selected patients (sacral neuromodulation, local injection of botulinum toxin, anterograde continence enemas), although with largely unpredictable outcomes. A further although irreversible step is surgery (subtotal colectomy with ileorectal anastomosis or stapled transanal rectal resection), which may confer some benefit to a few patients with refractoriness to medical treatments.

  8. Creep rupture strength and creep behavior of low-activation martensitic OPTIFER alloys. Final report; Das Zeitstandfestigkeits- und Kriechverhalten der niedrigaktivierenden martensitischen OPTIFER-Legierungen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Schirra, M.; Falkenstein, A.; Heger, S.; Lapena, J. [ITN-CIEMAT, Madrid (Spain). Programa de Materiales

    2001-07-01

    The creep rupture strength and creep experiments performed on low-activation OPTIFER alloys in the temperature range of 450-700 C shall be summarized in the present report. Together with the reference alloy of the type 9.5Cr1W-Mn-V-Ta, W-free variants (+Ge) with a more favorable activation and decay behavior shall be studied. Their smaller strength values are compensated by far better toughness characteristics. Of each development line, several batches of slightly varying chemical composition have been investigated over service lives of up to 40,000 h. Apart from the impact of a reference thermal treatment at a hardening temperature of 1075 C and an annealing temperature of 750 C, the influence of reduced hardening temperatures (up to 950 C) has been determined. A long-term use at increased temperatures (max. 550 C-20,000 h) produces an aging effect with strength being decreased in the annealed state. To determine this aging effect quantitatively, creep rupture experiments have been performed using specimens that were subjected to variable types of T/t annealing (550 -650 C, 330-5000 h). Based on all test results, minimum values for the 1% time-strain limit and creep rupture in the T range of 400-600 C can be given as design curves for 20,000 h. The minimum creep rates obtained from the creep curves recorded as a function of the experimental stress yield the stress exponent n (n=Norton) for the individual test temperatures. Creep behavior as a function of the test temperature yields the values for the effective activation energy of creeping Q{sub K}. The influence of a preceding temperature transient up to 800 C ({<=}Ac{sub 1b}) or 840 C (>Ac{sub 1b}) with subsequent creep rupture tests at 500 C and 550 C, respectively, shall be described. The results obtained for the OPTIFER alloys shall be compared with the results achieved for the Japanese 2% W-containing F82H-mod. alloy. (orig.) [German] Die Zeitstandfestigkeits- und Kriechversuche an den niedrigaktivierenden

  9. Refractories Quality Improvement for Glass Industry Upgrading

    Institute of Scientific and Technical Information of China (English)

    ZENG Dafan

    2009-01-01

    @@ 1 Glass Industry and Refractories Industry Closely Connect 1.1 Glass Development Drives Refractories Progress Refractories are indispensable to glass industry; the rapid development of glass industry drives the growth of refractories industry. China's glass industry developed slowly before the mid 1980s. The kilns and furnaces were backward and small-scale with furnace life of only 2-3 years; glass was produced with extremely low efficiency and poor quality. During that period, refractories for glass melting furnaces had very limited varieties and inferior quality. The fused cast refractories for advanced glass melting furnaces were imported, for the materials made in China could not meet the requirements, which seriously restrained the technical progress of China's glass industry.

  10. Refractory, Abrasive and Other Industrial Mineral Operations

    Data.gov (United States)

    Department of Homeland Security — This map layer includes refractory, abrasive, and other industrial minerals operations in the United States. The data represent commodities covered by the Minerals...

  11. Refractory ulcer of reconstructed gastric tube after esophagectomy: a case report.

    Science.gov (United States)

    Okamura, Yuki; Takeno, Shinsuke; Takahashi, Yoshiaki; Moroga, Toshihiko; Yamashita, Shin-ichi; Kawahara, Katsunobu

    2013-01-01

    We report a case in which rabeprazole cured gastric tube ulcer after esophagectomy for esophageal squamous cell carcinoma (ESCC). A 47-year-old Japanese man was referred to our hospital with refractory ulcer of the reconstructed gastric tube one year after esophagectomy for ESCC. The ulcer proved refractory to healing by the administration of omeprazole or lansoprazole, or eradication of Helicobacter pylori after examinations concerning ischemia, acid over-secretion and H. pylori infection. Finally, metabolizer type was examined for proton pump inhibitors (PPIs), revealing the patient as a hetero-extensive metabolizer for the CYP2C19 genotype. This suggested sensitivity to rabeprazole, but resistance to omeprazole and lansoprazole. The refractory ulcer was subsequently cured after changing the PPI to rabeprazole. Examination of PPI metabolizer type might thus be important, along with an investigation of ischemia, acid secretion and H. pylori infection in the treatment of refractory gastric tube ulcer after esophagectomy.

  12. LDRD final report on synthesis of shape-and size-controlled platinum and platinum alloy nanostructures on carbon with improved durability.

    Energy Technology Data Exchange (ETDEWEB)

    Shelnutt, John Allen; Garcia, Robert M.; Song, Yujiang; Moreno, Andres M.; Stanis, Ronald J.

    2008-10-01

    This project is aimed to gain added durability by supporting ripening-resistant dendritic platinum and/or platinum-based alloy nanostructures on carbon. We have developed a new synthetic approach suitable for directly supporting dendritic nanostructures on VXC-72 carbon black (CB), single-walled carbon nanotubes (SWCNTs), and multi-walled carbon nanotubes (MWCNTs). The key of the synthesis is to creating a unique supporting/confining reaction environment by incorporating carbon within lipid bilayer relying on a hydrophobic-hydrophobic interaction. In order to realize size uniformity control over the supported dendritic nanostructures, a fast photocatalytic seeding method based on tin(IV) porphyrins (SnP) developed at Sandia was applied to the synthesis by using SnP-containing liposomes under tungsten light irradiation. For concept approval, one created dendritic platinum nanostructure supported on CB was fabricated into membrane electrode assemblies (MEAs) for durability examination via potential cycling. It appears that carbon supporting is essentially beneficial to an enhanced durability according to our preliminary results.

  13. Thermal Transport in Refractory Carbides.

    Science.gov (United States)

    Thermal energy transport mechanisms in titanium carbide and zirconium carbide have been studied. Several compositions of vanadium carbide alloyed...with titanium carbide were used. The electronic component of the thermal conductivity exceeded the values computed using the classical value for L in

  14. Genetics Home Reference: iron-refractory iron deficiency anemia

    Science.gov (United States)

    ... refractory iron deficiency anemia iron-refractory iron deficiency anemia Enable Javascript to view the expand/collapse boxes. ... All Close All Description Iron-refractory iron deficiency anemia is one of many types of anemia , which ...

  15. Brazing Refractory Metals Used In High-Temperature Nuclear Instrumentation

    Energy Technology Data Exchange (ETDEWEB)

    A. J. Palmer; C. J. Woolstenhulme

    2009-06-01

    As part of the U. S. Department of Energy (DOE) sponsored Next Generation Nuclear Project (NGNP) currently ongoing at Idaho National Laboratory (INL), the irradiation performance of candidate high-temperature gas reactor fuels and materials is being evaluated at INL’s Advanced Test Reactor (ATR). The design of the first Advanced Gas Reactor (AGR 1) experiment, currently being irradiated in the ATR, required development of special techniques for brazing niobium and molybdenum. Brazing is one technique used to join refractory metals to each other and to stainless steel alloys. Although brazing processes are well established, it is difficult to braze niobium, molybdenum, and most other refractory metals because they quickly develop adherent oxides when exposed to room-temperature air. Specialized techniques and methods were developed by INL to overcome these obstacles. This paper describes the techniques developed for removing these oxides, as well as the ASME Section IX-qualified braze procedures that were developed as part of the AGR-1 project. All brazes were made using an induction coil with an inert or reducing atmosphere at low pressure. Other parameters, such as filler metals, fluxes used, and general setup procedures, are also discussed.

  16. Management of refractory cardiogenic shock.

    Science.gov (United States)

    Reyentovich, Alex; Barghash, Maya H; Hochman, Judith S

    2016-08-01

    Cardiogenic shock is a life-threatening condition that occurs in response to reduced cardiac output in the presence of adequate intravascular volume and results in tissue hypoxia. Cardiogenic shock has several underlying aetiologies, with the most common being acute myocardial infarction (AMI). Refractory cardiogenic shock presents as persistent tissue hypoperfusion despite administration of adequate doses of two vasoactive medications and treatment of the underlying aetiology. Investigators of the SHOCK trial reported a long-term mortality benefit of emergency revascularization for shock complicating AMI. Since the publication of the SHOCK trial and subsequent guideline recommendations, the increase in community-based use of percutaneous coronary intervention for this condition has resulted in a significant decline in mortality. Despite these successes in the past 15 years, mortality still remains exceptionally high, particularly in patients with refractory cardiogenic shock. In this Review, we discuss the aetiology and pathophysiology of cardiogenic shock and summarize the data on the available therapeutics and their limitations. Although new mechanical circulatory support devices have been shown to improve haemodynamic variables in patients with shock complicating AMI, they did not improve clinical outcomes and are associated with high costs and complications.

  17. Refractory Pellet for Hot Blast Stove

    Institute of Scientific and Technical Information of China (English)

    Wang Jing; Peng Xigao

    2011-01-01

    1 Scope This standard specifies the term,definition,classification,specification,technical requirements,test methods,quality appraisal procedures,packing,marking,transportation,storage,and quality certificate of refractory pellet for hot blast stove.This standard is applicable to refractory pellet for hot blast stove.

  18. Spectral reflecting characteristics of dinas refractory

    Energy Technology Data Exchange (ETDEWEB)

    Zapechnikov, V.N.; Pushkin, V.T.; Zen' kovskii, A.G.

    1987-09-01

    This article outlines a nondestructive testing format which uses spectral reflectance to assess the remaining service life, the thermal degradation, and the insulating effectiveness of refractories used as insulating liners in glass melters. Thermal as well as mechanical influences on the reflectance behavior of several refractories are discussed.

  19. Modern technologies of refractory glaucoma treatment. Review

    Directory of Open Access Journals (Sweden)

    A. Yu. Rascheskov

    2014-07-01

    Full Text Available this article presents a review of available literature concerning basic directions of refractory glaucoma treatment. the surgical management of refractory glaucoma is presented by two main groups of surgical techniques: filtering surgery (including surgery with the use of antimetabolites and implants and cyclodestructive procederes. types of glaucoma drainages are described, modern valve drainage system is presented.

  20. Research on High Performance New Refractories

    Institute of Scientific and Technical Information of China (English)

    Zhong Xiangchong

    2007-01-01

    @@ At the age of 86,Prof.Zhong Xiangchong has his new book-"Research on High Performance New Refractories" published by Henan Science and Technology Publishing House to commemorate his 65 years service in the refractories science and technology including the recent 6 years at High Temperature Ceramics Institute which he founded in Zhengzhou University in 2001.

  1. Case 40. Misdiagnosis of refractory macrocytic anemia.

    Science.gov (United States)

    Stringaris, Kate; Bain, Barbara

    2008-11-01

    A diagnosis of myelodysplastic syndrome, refractory anemia subtype, was made in an elderly Indian woman on the basis of a refractory macrocytic anemia with normal vitamin B(12) and folate assays, normal thyroid function, essentially normal liver function and normal cytogenetic analysis. Disease evolution revealed that the diagnosis was erroneous.

  2. Structural thermodynamics of alloys

    CERN Document Server

    Manenc, Jack

    1973-01-01

    Technical progress has for a very long time been directly dependent on progress in metallurgy, which is itself connected with improvements in the technology of alloys. Metals are most frequently used in the form of alloys for several reasons: the quantity of pure metal in its native state in the earth's crust is very limited; pure metals must be extracted from ores which are themselves impure. Finally, the methods of treatment used lead more easily to alloys than to pure metals. The most typical case is that of iron, where a pure ore may be found, but which is the starting point for cast iron or steel, alloys of iron and carbon. In addition, the properties of alloys are in general superior to those of pure metals and modem metallurgy consists of controlling these properties so as to make them conform to the requirements of the design office. Whilst the engineer was formerly compelled to adapt his designs and constructions to the materials available, such as wood, stone, bronze, iron, cast iron and ordinary st...

  3. How Social and Refractory Is the Social Psychological Refractory Period?

    Science.gov (United States)

    Wühr, Peter; Heuer, Herbert

    2017-07-01

    The social psychological refractory period (PRP) effect refers to an increase in RT to the second of two successive stimuli when another person responds to the first stimulus (shared dual-task condition) rather than when a single person responds to both stimuli (individual dual-task condition). We investigated (a) whether a social PRP effect would occur without explicit instruction concerning task priority and (b) whether there are crosstalk effects in the shared dual-task situation. We observed a strong PRP effect together with a small crosstalk effect in the individual dual-task condition, but in the shared dual-task condition both effects were absent. These findings suggest that the explicit instruction to perform responses in a fixed order is necessary to obtain the social PRP effect. In the individual dual-task condition, sequential processing can be seen as a means to reduce or prevent crosstalk effects, which is not necessary in the shared dual-task condition.

  4. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Musa Karakus; Jun Wei

    2005-03-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

  5. Refractory for Black Liquor Gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Musa Karakus; Xiaoting Laing

    2005-10-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

  6. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Musa Karakus; Xiaoting Liang; Alireza Rezaie

    2004-10-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

  7. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Musa Karakus; Xiaoting Liang; Jun Wei

    2005-04-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

  8. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Musa Karakus; Xiaoting Liang; Jun Wei

    2005-01-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

  9. Refractory for Black Liquor Gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Musa Karakus; Xiaoting Liang

    2005-10-01

    The University of Missouri-Rolla identified materials that permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project was to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study attempted to define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials were selected/developed that either react with the gasifier environment to form protective surfaces in

  10. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Musa Karakus; Xiaoting Liang

    2005-07-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

  11. Refractory for Black Liquor Gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Alireza Rezaie; Xiaoting Liang; Musa Karakus; Jun Wei

    2005-12-01

    The University of Missouri-Rolla identified materials that permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project was to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study attempted to define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials were selected or developed that reacted with the gasifier environment to form protective surfaces in

  12. Refractory for Black Liquor Gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick; Musa Karakus; Alireza Rezaie

    2004-03-30

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

  13. Refractory for Black Liquor Gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Alireza Rezaie

    2003-08-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the materials problems encountered during the operation of low-pressure high-temperature (LFHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

  14. Refractory for Black Liquor Gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Alireza Rezaie

    2003-12-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the materials problems encountered during the operation of low-pressure high-temperature (LFHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

  15. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Musa Karakus; Xiaoting Liang; Alireza Rezaie

    2004-07-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

  16. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr.; Alireza Rezaie

    2004-04-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the materials problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

  17. Refractory for Black Liquor Gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    Robert E. Moore; William L. Headrick; Alireza Rezaie

    2003-03-31

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the materials problems encountered during the operation of low-pressure high-temperature (LFHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

  18. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr.; Alireza Rezaie

    2003-12-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the materials problems encountered during the operation of low-pressure high-temperature (LFHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

  19. Primordial Compositions of Refractory Inclusions

    Energy Technology Data Exchange (ETDEWEB)

    Grossman, L; Simon, S B; Rai, V K; Thiemens, M H; Hutcheon, I D; Williams, R W; Galy, A; Ding, T; Fedkin, A V; Clayton, R N; Mayeda, T K

    2008-02-20

    Bulk chemical and oxygen, magnesium and silicon isotopic compositions were measured for each of 17 Types A and B refractory inclusions from CV3 chondrites. After bulk chemical compositions were corrected for non-representative sampling in the laboratory, the Mg and Si isotopic compositions of each inclusion were used to calculate its original chemical composition assuming that the heavy-isotope enrichments of these elements are due to Rayleigh fractionation that accompanied their evaporation from CMAS liquids. The resulting pre-evaporation chemical compositions are consistent with those predicted by equilibrium thermodynamic calculations for high-temperature nebular condensates but only if different inclusions condensed from nebular regions that ranged in total pressure from 10{sup -6} to 10{sup -1} bar, regardless of whether they formed in a system of solar composition or in one enriched in OC dust relative to gas by a factor of ten relative to solar composition. This is similar to the range of total pressures predicted by dynamic models of the solar nebula for regions whose temperatures are in the range of silicate condensation temperatures. Alternatively, if departure from equilibrium condensation and/or non-representative sampling of condensates in the nebula occurred, the inferred range of total pressure could be smaller. Simple kinetic modeling of evaporation successfully reproduces observed chemical compositions of most inclusions from their inferred pre-evaporation compositions, suggesting that closed-system isotopic exchange processes did not have a significant effect on their isotopic compositions. Comparison of pre-evaporation compositions with observed ones indicates that 80% of the enrichment in refractory CaO + Al{sub 2}O{sub 3} relative to more volatile MgO + SiO{sub 2} is due to initial condensation and 20% due to subsequent evaporation for both Type A and Type B inclusions.

  20. Aluminum alloy

    Science.gov (United States)

    Blackburn, Linda B. (Inventor); Starke, Edgar A., Jr. (Inventor)

    1989-01-01

    This invention relates to aluminum alloys, particularly to aluminum-copper-lithium alloys containing at least about 0.1 percent by weight of indium as an essential component, which are suitable for applications in aircraft and aerospace vehicles. At least about 0.1 percent by weight of indium is added as an essential component to an alloy which precipitates a T1 phase (Al2CuLi). This addition enhances the nucleation of the precipitate T1 phase, producing a microstructure which provides excellent strength as indicated by Rockwell hardness values and confirmed by standard tensile tests.

  1. Refractories for Industrial Processing. Opportunities for Improved Energy Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Hemrick, James G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hayden, H. Wayne [Metals Manufacture Process and Controls Technology, Inc., Oak Ridge, TN (United States); Angelini, Peter [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Moore, Robert E. [R.E. Moore Associates, Maricopa, AZ (United States); Headrick, William L. [R.E. Moore Associates, Maricopa, AZ (United States)

    2005-01-01

    Refractories are a class of materials of critical importance to manufacturing industries with high-temperature unit processes. This study describes industrial refractory applications and identifies refractory performance barriers to energy efficiency for processing. The report provides recommendations for R&D pathways leading to improved refractories for energy-efficient manufacturing and processing.

  2. Alkaline sulfide pretreatment of an antimonial refractory Au-Ag ore for improved cyanidation

    Science.gov (United States)

    Alp, Ibrahim; Celep, Oktay; Deveci, Haci

    2010-11-01

    This paper presents the alkaline sulfide pretreatment of an antimonial refractory gold and silver ore. In the ore, gold occurs mainly as gold-silver alloys and as associated with quartz and framboidal pyrite grains, and, to a small extent, as the inclusions within antimonial sulfides. Silver is present extensively as antimonial sulfides such as andorite. Alkaline sulfide pretreatment was shown to allow the decomposition of the antimonial sulfide minerals (up to 98% Sb removal) and to remarkably improve the amenability of gold (e.g., from silver (e.g., from leaching. An increase in reagent concentration (1-4 mol/L Na2S or NaOH) and temperature (20-80°C), and a decrease in particle size seem to produce an enhancing effect on metal extraction. These findings suggest that alkaline sulfide leaching can be suitably used as a chemical pretreatment method prior to the conventional cyanidation for antimonial refractory gold and silver ores.

  3. Fireclay Refractory Bricks for Hot Blast Stove

    Institute of Scientific and Technical Information of China (English)

    Wang Jing; Zhang Yongfang; Chai Junlan

    2008-01-01

    @@ 1 Scope This standard specifies the classification, shape, dimension, technical requirements, test method,inspection rules, packing, marking,transportation,storage and quality certification of fireclay refractory bricks for hot blast stove.

  4. Spalling Resistance Fast-drying Refractory Castables

    Institute of Scientific and Technical Information of China (English)

    Wang Jing; Peng Xigao

    2010-01-01

    @@ 1 Scope This standard specifies the term and definition,classification, technical requirements, test methods,quality appraisal procedures, packing, marking, transportation, storage, and quality certificate of spalling resistance fast-drying refractory castables.

  5. Ultra High Temperature Refractory Materials Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Legacy refractory materials that have origins dating to the original Saturn program are commonly used in current launch facilities. Although they failure to meet the...

  6. Ultra High Temperature Refractory Materials Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Legacy refractory materials that have origins dating to the original Saturn program are commonly used in current launch facilities. Although they fail to meet the...

  7. Alumina Carbon Refractory Products for Continuous Casting

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ 1 Scope This standard specifies the classification.techni-cal requirements,test methods,inspection rules,packing,marking,transportation,storage and quality certificate of alumina carbon refractory products for continuous casting.

  8. Testing Consent Order on Refractory Ceramic Fibers

    Science.gov (United States)

    This notice announces that EPA has signed signed an enforceable testing consent order under the Toxic Substances Control Act (TSCA), 15 U.S.C. section 2601 at seq., with three of the primary producers of refractory ceramic fibers (RCF).

  9. Emergency coronary angioplasty in refractory unstable angina

    NARCIS (Netherlands)

    P.J. de Feyter (Pim); P.W.J.C. Serruys (Patrick); M.J.B.M. van den Brand (Marcel); K. Balakumaran (Kulasekaram); A.L. Soward; P.G. Hugenholtz (Paul); A.E.R. Arnold (Alfred); B. Mochtar (Bas)

    1985-01-01

    textabstractWe performed percutaneous transluminal coronary angioplasty as an emergency procedure in 60 patients with unstable angina pectoris that was refractory to treatment with maximally tolerated doses of beta-blockers, calcium antagonists, and intravenous nitroglycerin. The initial success

  10. Prognostic Factors for Refractory Status Epilepticus

    Directory of Open Access Journals (Sweden)

    J. Gordon Millichap

    2013-03-01

    Full Text Available Researchers at the Mayo Clinic, Rochester, MN studied the outcome and identified prognostic factors for refractory status epilepticus (RSE in 54 adult patients, median age 52 years [range 18-93].

  11. Situation of China's Refractories Industry in Last Sixty Years

    Institute of Scientific and Technical Information of China (English)

    HUO Jiangping; PAN Shangxin; LI Chaowen

    2009-01-01

    The annual output of China's refractories in 1949 was 74 thousand tons, and was 29.11 million tons in 2007, which was 65% of the world total refractories output. The export of China's refractory products and raw materials in 2008 was 6.18 million tons, which were exported to hundreds of countries and regions in the world. China is a big country in the field of refractories production and refractories export, which has devoted a lot to relative high temperature industry.

  12. Method of making a composite refractory material

    Science.gov (United States)

    Morrow, Marvin S.; Holcombe, Cressie E.

    1995-01-01

    A composite refractory material is prepared by combining boron carbide with furan resin to form a mixture containing about 8 wt. % furan resin. The mixture is formed into a pellet which is placed into a grit pack comprising an oxide of an element such as yttrium to form a sinterable body. The sinterable body is sintered under vacuum with microwave energy at a temperature no greater than 2000.degree. C. to form a composite refractory material.

  13. The modified atkins diet in refractory epilepsy.

    Science.gov (United States)

    Sharma, Suvasini; Jain, Puneet

    2014-01-01

    The modified Atkins diet is a less restrictive variation of the ketogenic diet. This diet is started on an outpatient basis without a fast, allows unlimited protein and fat, and does not restrict calories or fluids. Recent studies have shown good efficacy and tolerability of this diet in refractory epilepsy. In this review, we discuss the use of the modified Atkins diet in refractory epilepsy.

  14. Neuromodulation in refractory epilepsy: Brazilian specialists consensus

    Directory of Open Access Journals (Sweden)

    Vera Cristina Terra

    Full Text Available ABSTRACT Epilepsy is a potentially devastating brain disorder characterized by a predisposition to spontaneous epileptic seizures. In patients with medically refractory epilepsy, new non-pharmacological therapeutic approaches may be considered. In this scenario, palliative surgery such as vagus nerve stimulation (VNS or deep brain stimulation (DBS may be indicated in a subset of patients. In this paper we make recommendations for the use of VNS and DBS in patients in Brazil with refractory epilepsy.

  15. The Modified Atkins Diet in Refractory Epilepsy

    Directory of Open Access Journals (Sweden)

    Suvasini Sharma

    2014-01-01

    Full Text Available The modified Atkins diet is a less restrictive variation of the ketogenic diet. This diet is started on an outpatient basis without a fast, allows unlimited protein and fat, and does not restrict calories or fluids. Recent studies have shown good efficacy and tolerability of this diet in refractory epilepsy. In this review, we discuss the use of the modified Atkins diet in refractory epilepsy.

  16. REFRACTORY THROMBOCYTOPENIA AND NEUTROPENIA: A DIAGNOSTIC CHALLENGE

    Directory of Open Access Journals (Sweden)

    Emmanuel Gyan

    2015-02-01

    Full Text Available Background. The 2008 WHO classification identified refractory cytopenia with unilineage dysplasia (RCUD as a composite entity encompassing refractory anemia, refractory thrombocytopenia (RT, and refractory neutropenia (RN, characterized by 10% or more dysplastic cells in the bone marrow respective lineage. The diagnosis of RT and RN is complicated by several factors.  Diagnosing RT first requires exclusion of familial thrombocytopenia, chronic auto-immune thrombocytopenia, concomitant medications, viral infections, or hypersplenism. Diagnosis of RN should also be made after ruling out differential diagnoses such as ethnic or familial neutropenia, as well as acquired, drug-induced, infection-related or malignancy-related neutropenia. An accurate quantification of dysplasia should be performed in order to distinguish RT or RN from the provisional entity named idiopathic cytopenia of unknown significance (ICUS. Cytogenetic analysis, and possibly in the future somatic mutation analysis (of genes most frequently mutated in MDS, and flow cytometry analysis aberrant antigen expression on myeloid cells may help in this differential diagnosis. Importantly, we and others found that, while isolated neutropenia and thrombocytopenia are not rare in MDS, those patients can generally be classified (according to WHO 2008 classification as refractory cytopenia with multilineage dysplasia or refractory anemia with excess blasts, while RT and RN (according to WHO 2008 are quite rare.These results suggest in particular that identification of RT and RN as distinct entities could be reconsidered in future WHO classification updates.

  17. Advances in Modern Refractory Castables

    Institute of Scientific and Technical Information of China (English)

    ZHOU Ningsheng; HU Shuhe; ZHANG Sanhua

    2004-01-01

    Recent developments in terms of binding system, new material system, installation method and pre-cast shapes of refractory castables are introduced and discussed. In authors view, binding system is advancing on the one hand towards "purification" to minimize impurity components from binder materials, and on the other hand "stabilization" to minimize the structure destroy by volatility and decomposition of binder materials. Challenges of higher service temperature, slag resistance, clean steel production and better thermal shock resistance have promoted the booming of new varieties of castables including MgObased, natural flake graphite containing and non-oxides like Si3 N4, AlON and SiAlON containing castables. Installation technique is developing towards convenience,simplification and high efficiency. Advancement in installation and dry-out is of an incentive to the boost of selfflow castables, shotcreting castables, infiltration casting,quick dry-out castables and pre-cast shapes. Along with the increased adoption of pre-cast shapes of castables, the boundary between "shaped" and "unshaped" is becoming vague.

  18. Advances in Modern Refractory Castables

    Institute of Scientific and Technical Information of China (English)

    ZHOUNingsheng; HUShuhe; ZHANGSanhua

    2004-01-01

    Recent developments in terms of binding system, new material system, installation method and pre-cast shapes of refractory castables are introduced and discussed. In authors' view, binding system is advancing on the one hand towards "purification" to minimize impurity components from binder materials, and on the other hand "stabilization" to minimize the structure destroy by volatility and decomposition of binder materials. Challenges of higher service temperature, slag resistance, clean steel production and better thermal shock resistance have promoted the booming of new varieties of castables including MgO based, natural flake graphite containing and non-oxides like Sis N4, AION and SIMON containing castables. Installation technique is developing towards convenience, simplification and high efficiency. Advancement in installation and dry-out is of an incentive to the boost of selfflow castables, shotcreting castables, infiltration casting, quick dry-out castables and pre-cast shapes. Along wit hthe increased adoption of pre-cast shapes of castables, the boundary between "shaped" and " unshaped " is becoming vague.

  19. VNS for refractory status epilepticus.

    Science.gov (United States)

    Zeiler, F A; Zeiler, K J; Teitelbaum, J; Gillman, L M; West, M

    2015-05-01

    Our goal was to perform a systematic review of the literature on the insertion of vagal nerve stimulators (VNS) for refractory status epilepticus (RSE) and its impact on the control of RSE. All articles from MEDLINE, BIOSIS, EMBASE, Global Health, HealthStar, Scopus, Cochrane Library, the International Clinical Trials Registry Platform, clinicaltrials.gov (inception to June 2014), reference lists of relevant articles, and gray literature were searched. The strength of evidence was adjudicated using both the Oxford and GRADE methodology by two independent reviewers (FZ and MW). Overall, 17 studies were identified, with 7 manuscripts and 10 meeting abstracts. A total of 28 patients were treated. In those with generalized RSE, 76% displayed cessation of RSE with VNS insertion. In cases of focal RSE, 25% responded to VNS insertion. Few adverse effects related to VNS insertion were described. We currently cannot recommend the use of VNS for RSE. Oxford level 4, GRADE D evidence exists to suggest improvement in seizure control with the use of urgent VNS in generalized RSE. No comments can be made on the utility of VNS in focal RSE. Further prospective study is warranted. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Microstructures and properties of aluminum die casting alloys

    Energy Technology Data Exchange (ETDEWEB)

    M. M. Makhlouf; D. Apelian; L. Wang

    1998-10-01

    This document provides descriptions of the microstructure of different aluminum die casting alloys and to relate the various microstructures to the alloy chemistry. It relates the microstructures of the alloys to their main engineering properties such as ultimate tensile strength, yield strength, elongation, fatigue life, impact resistance, wear resistance, hardness, thermal conductivity and electrical conductivity. Finally, it serves as a reference source for aluminum die casting alloys.

  1. Electrical Resistance Alloys and Low-Expansion Alloys

    DEFF Research Database (Denmark)

    Kjer, Torben

    1996-01-01

    The article gives an overview of electrical resistance alloys and alloys with low thermal expansion. The electrical resistance alloys comprise resistance alloys, heating alloys and thermostat alloys. The low expansion alloys comprise alloys with very low expansion coefficients, alloys with very low...

  2. Phonon broadening in high entropy alloys

    Science.gov (United States)

    Körmann, Fritz; Ikeda, Yuji; Grabowski, Blazej; Sluiter, Marcel H. F.

    2017-09-01

    Refractory high entropy alloys feature outstanding properties making them a promising materials class for next-generation high-temperature applications. At high temperatures, materials properties are strongly affected by lattice vibrations (phonons). Phonons critically influence thermal stability, thermodynamic and elastic properties, as well as thermal conductivity. In contrast to perfect crystals and ordered alloys, the inherently present mass and force constant fluctuations in multi-component random alloys (high entropy alloys) can induce significant phonon scattering and broadening. Despite their importance, phonon scattering and broadening have so far only scarcely been investigated for high entropy alloys. We tackle this challenge from a theoretical perspective and employ ab initio calculations to systematically study the impact of force constant and mass fluctuations on the phonon spectral functions of 12 body-centered cubic random alloys, from binaries up to 5-component high entropy alloys, addressing the key question of how chemical complexity impacts phonons. We find that it is crucial to include both mass and force constant fluctuations. If one or the other is neglected, qualitatively wrong results can be obtained such as artificial phonon band gaps. We analyze how the results obtained for the phonons translate into thermodynamically integrated quantities, specifically the vibrational entropy. Changes in the vibrational entropy with increasing the number of elements can be as large as changes in the configurational entropy and are thus important for phase stability considerations. The set of studied alloys includes MoTa, MoTaNb, MoTaNbW, MoTaNbWV, VW, VWNb, VWTa, VWNbTa, VTaNbTi, VWNbTaTi, HfZrNb, HfMoTaTiZr.

  3. Bulk amorphous Mg-based alloys

    DEFF Research Database (Denmark)

    Pryds, Nini

    2004-01-01

    The present paper describes the preparation and properties of bulk amorphous quarternary Mg-based alloys and the influence of additional elements on the ability of the alloy to form bulk amorphous. The main goal is to find a Mg-based alloy system which shows both high strength to weight ratio...... and a low glass transition temperature. The alloys were prepared by using a relatively simple technique, i.e. rapid cooling of the melt in a copper wedge mould. The essential structural changes that are achieved by going from the amorphous to the crystalline state through the supercooled liquid state...... are discussed in this paper. On the basis of these measurements phase diagrams of the different systems were constructed. Finally, it is demonstrated that when pressing the bulk amorphous alloy onto a metallic dies at temperatures within the supercooled liquid region, the alloy faithfully replicates the surface...

  4. Wetting behavior of alternative solder alloys

    Energy Technology Data Exchange (ETDEWEB)

    Hosking, F.M.; Vianco, P.T.; Hernandez, C.L.; Rejent, J.A.

    1993-07-01

    Recent economic and environmental issues have stimulated interest in solder alloys other than the traditional Sn-Pb eutectic or near eutectic composition. Preliminary evaluations suggest that several of these alloys approach the baseline properties (wetting, mechanical, thermal, and electrical) of the Sn-Pb solders. Final alloy acceptance will require major revisions to existing industrial and military soldering specifications. Bulk alloy and solder joint properties are consequently being investigated to validate their producibility and reliability. The work reported in this paper examines the wetting behavior of several of the more promising commercial alloys on copper substrates. Solder wettability was determined by the meniscometer and wetting balance techniques. The wetting results suggest that several of the alternative solders would satisfy pretinning and surface mount soldering applications. Their use on plated through hole technology might be more difficult since the alloys generally did not spread or flow as well as the 60Sn-40Pb solder.

  5. High temperature resistant cermet and ceramic compositions. [for thermal resistant insulators and refractory coatings

    Science.gov (United States)

    Phillips, W. M. (Inventor)

    1978-01-01

    High temperature oxidation resistance, high hardness and high abrasion and wear resistance are properties of cermet compositions particularly to provide high temperature resistant refractory coatings on metal substrates, for use as electrical insulation seals for thermionic converters. The compositions comprise a sintered body of particles of a high temperature resistant metal or metal alloy, preferably molybdenum or tungsten particles, dispersed in and bonded to a solid solution formed of aluminum oxide and silicon nitride, and particularly a ternary solid solution formed of a mixture of aluminum oxide, silicon nitride and aluminum nitride. Ceramic compositions comprising a sintered solid solution of aluminum oxide, silicon nitride and aluminum nitride are also described.

  6. Measurements of Total Hemispherical Emissivity of Several Stably Oxidized Metals and Some Refractory Oxide Coatings

    Science.gov (United States)

    Wade, William R.

    1959-01-01

    A description of the apparatus and methods used for obtaining total hemispherical emissivity is presented, and data for several stably oxidized metals are included. The metals which were tested included type 347 stainless steel, tungsten, and Haynes alloys B, C, X, and 25. No values of emissivity were obtained for tungsten or Haynes alloy B because of the nature of the oxides produced. The refractory oxide coatings tested were flame-sprayed alumina and zirconia. The results of the investigation indicate that strongly adherent, oxidized surfaces of a high stable emissivity can be produced on type 347 stainless steel for which the total hemispherical emissivity varied from 0.87 to 0.91 for temperatures from 600 F to 2,000 F. For this same temperature range, the Haynes alloys tested showed values of total hemispherical emissivity from 0.90 to 0.96 for alloy C, from 0.85 to 0.88 for alloy X, and from 0.85 to 0.89 for alloy 25. Haynes alloy B and tungsten formed nonadherent oxides at elevated temperatures and, therefore, stable emissivities were not obtained. The results obtained for the flame-sprayed ceramics (alumina and zirconia) showed considerably higher values of total emissivity than those measured for coatings applied by other methods. Emissivity values ranging from 0.69 to 0.44 for aluminum oxide and from 0.62 to 0.44 for zirconium oxide were measured for temperatures from 800 F to 2,000 F.

  7. Effect of nanostructured composite powders on the structure and strength properties of the high-temperature inconel 718 alloy

    Science.gov (United States)

    Cherepanov, A. N.; Ovcharenko, V. E.

    2015-12-01

    The experimental results of the effect of powder nanomodifiers of refractory compounds on the strength properties, the macro- and microstructure of the high-temperature Inconel 718 alloy have been presented. It has been shown that the introduction of powder modifiers into the melt leads to a decrease in the average grain size by a factor of 1.5-2 in the alloy. The long-term tensile strength of the alloy at 650°C increases 1.5-2 times, and the number of cycles at 482°C before fracture grows by more than three times. The effect of nanoparticles on the grain structure and strength properties of the alloy is due to an increase in the number of generated crystallization centers and the formation of nanoparticle clusters of refractory compounds at boundaries and junctions in the formed grain structure, which hinder the development of recrystallization processes in the alloy.

  8. Thermodynamic and Experimental Investigations of High-Temperature Refractory Corrosion by Molten Slags

    Science.gov (United States)

    Wagner, Christoph; Wenzl, Christine; Gregurek, Dean; Kreuzer, Daniel; Luidold, Stefan; Schnideritsch, Holger

    2017-02-01

    Corrosion mechanisms between MgO refractory substrates and FeNi slags were investigated. The FeNi slags taken into consideration represent a simple synthetically mixed slag with specific oxides and a real slag from a ferroalloy producer. The MgO refractory substrates with the specimens of FeNi slag were heated in a hot-stage microscope at 10 K/min from room temperature to three different temperatures 1573 K, 1723 K, and 1923 K (1300 °C, 1450 °C, and 1650 °C). The experiments were carried out under a controlled gas atmosphere that simulates the relevant process conditions. The corrosion mechanisms of each system were followed by scanning electron microscope analyses. The results obtained showed that slag corrosion dominates, with a pronounced partial dissolution of refractory fines forming Mg-silicates of type forsterite. It was also observed that iron oxide present in the slag diffused into the coarse refractory grains forming magnesiowustite. Finally, the results obtained were compared with those predicted by FACTSAGE software to understand the corrosion mechanisms and draw implications for improving the refractory performance and lifetime.

  9. Thermodynamic and Experimental Investigations of High-Temperature Refractory Corrosion by Molten Slags

    Science.gov (United States)

    Wagner, Christoph; Wenzl, Christine; Gregurek, Dean; Kreuzer, Daniel; Luidold, Stefan; Schnideritsch, Holger

    2016-12-01

    Corrosion mechanisms between MgO refractory substrates and FeNi slags were investigated. The FeNi slags taken into consideration represent a simple synthetically mixed slag with specific oxides and a real slag from a ferroalloy producer. The MgO refractory substrates with the specimens of FeNi slag were heated in a hot-stage microscope at 10 K/min from room temperature to three different temperatures 1573 K, 1723 K, and 1923 K (1300 °C, 1450 °C, and 1650 °C). The experiments were carried out under a controlled gas atmosphere that simulates the relevant process conditions. The corrosion mechanisms of each system were followed by scanning electron microscope analyses. The results obtained showed that slag corrosion dominates, with a pronounced partial dissolution of refractory fines forming Mg-silicates of type forsterite. It was also observed that iron oxide present in the slag diffused into the coarse refractory grains forming magnesiowustite. Finally, the results obtained were compared with those predicted by FACTSAGE software to understand the corrosion mechanisms and draw implications for improving the refractory performance and lifetime.

  10. Modeling dissolution in aluminum alloys

    Science.gov (United States)

    Durbin, Tracie Lee

    2005-07-01

    alloys when compared with published experimental results. The influence of inter-particle spacing is examined and shown to have a significant effect on dissolution kinetics. Finally, the impact of multiple particles of various sizes interacting in an aluminum matrix is investigated. It is shown that smaller particles dissolve faster, as expected, but influence the dissolution of larger particles through soft-impingement, even after the smaller particles have disappeared.

  11. Analysis on the Causes for Refractory GERD

    Institute of Scientific and Technical Information of China (English)

    陈婕; 许军英; 徐勇; 谢小平; 易粹琼; 侯晓华

    2002-01-01

    To analyze the causes of failure in conventional treatment to refractory gastroesophageal reflux diseases (GERD) patients, 16 refractory GERD patients (group R) and 16 eases of GERD primarily diagnosed (group P) were studied. Endoscopy, pathologic examination and 14C urea breath test were conducted in every patient. 24 h ambulatory pH and bilirubin monitoring were performed with Digitrapper MI Ⅲ and Synetics Bilitec 2000. It was found that esophagitis in group R was more severe than in group P. The rate of Helicobacter pylori infection in group R was significantly lower than in group P. Fraction time pH below 4. 00 was not longer while the bile reflux represented by fraction time abs above 0. 14 was greater for patients in the group R as compared with those in the group P. The mixed refluxes and pure bile refluxes between the two groups had significant difference. The reflux episodes in the group R mainly occurred during nights. These results indicated that severe esophagitis, especially Barrett's esophagus with complications makes it difficult to control GERD. Severe duodenogastroesophageal refluxes (DGER) are often accompanied by refractory GERD. Mixed refluxes aggravate the esophageal injuries. Pure bile refluxes and nocturnal refluxes may cause failure of administration of proton pump inhibitors (PPI) in the morning. Helicobacter pylori infection and acid refluxes may not be the direct cause of refractoriness. Individual refractory GERD patient without abnormal results on pH or bile reflux recently should be diagnosed again.

  12. Identification of platelet refractoriness in oncohematologic patients

    Directory of Open Access Journals (Sweden)

    Aline Aparecida Ferreira

    2011-01-01

    Full Text Available OBJECTIVES: To identify the occurrence and the causes of platelet refractoriness in oncohematologic patients. INTRODUCTION: Platelet refractoriness (unsatisfactory post-transfusion platelet increment is a severe problem that impairs the treatment of oncohematologic patients and is not routinely investigated in most Brazilian services. METHODS: Forty-four episodes of platelet concentrate transfusion were evaluated in 16 patients according to the following parameters: corrected count increment, clinical conditions and detection of anti-platelet antibodies by the platelet immunofluorescence test (PIFT and panel reactive antibodies against human leukocyte antigen class I (PRA-HLA. RESULTS: Of the 16 patients evaluated (median age: 53 years, nine (56% were women, seven of them with a history of pregnancy. An unsatisfactory increment was observed in 43% of the transfusion events, being more frequent in transfusions of random platelet concentrates (54%. Platelet refractoriness was confirmed in three patients (19%, who presented immunologic and non-immunologic causes. Alloantibodies were identified in eight patients (50% by the PIFT and in three (19% by the PRA-HLA. Among alloimmunized patients, nine (64% had a history of transfusion, and three as a result of pregnancy (43%. Of the former, two were refractory (29%. No significant differences were observed, probably as a result of the small sample size. CONCLUSION: The high rate of unsatisfactory platelet increment, refractoriness and alloimmunization observed support the need to set up protocols for the investigation of this complication in all chronically transfused patients, a fundamental requirement for the guarantee of adequate management.

  13. Microstructural characterization of an irradiated RERTR-6 U-7Mo/AA4043 alloy dispersion fuel plate specimen blister-tested to a final temperature of 500 °C

    Science.gov (United States)

    Keiser, Dennis D.; Jue, Jan-Fong; Gan, Jian; Miller, Brandon D.; Robinson, Adam B.; Madden, James W.; Ross Finlay, M.; Moore, Glenn; Medvedev, Pavel; Meyer, Mitch

    2017-05-01

    The Material Management and Minimization (M3) Reactor Conversion Program, in the past called the Reduced Enrichment for Research and Test Reactor (RERTR) Program, is developing low-enriched uranium (LEU) fuels for application in research and test reactors. U-Mo alloy dispersion fuel is one type being developed. Blister testing has been performed on different fuel plate samples to determine the margin to failure for fuel plates irradiated to different fission densities. Microstructural characterization was performed using scanning electron microscopy and transmission electron microscopy on a sample taken from a U-7Mo/AA4043 matrix dispersion fuel plate irradiated in the RERTR-6 experiment that was blister-tested up to a final temperature of 500 °C. The results indicated that two types of grain/cell boundaries were observed in the U-7Mo fuel particles, one with a relatively low Mo content and fission gas bubbles and a second type enriched in Si, due to interdiffusion from the Si-containing matrix, with little evidence of fission gas bubbles. With respect to the behavior of the major fission gas Xe, a significant amount of the Xe was still observed within the U-7Mo fuel particle, along with microns into the AA4043 matrix. For the fuel/matrix interaction layers that form during fabrication and then grow during irradiation, they change from the as-irradiated amorphous structure to one that is crystalline after blister testing. In the AA4043 matrix, the original Si-rich precipitates, which are typically observed in as-irradiated U-Mo dispersion fuel, get consumed due to interdiffusion with the U-7Mo fuel particles during the blister test. Finally, the fission gas bubbles that were originally around 3 nm in diameter and resided on a fission gas superlattice (FGS) in the intragranular regions of as-irradiated U-7Mo fuel grew in size (up to ∼20 nm diameter) during blister testing and, in many areas, are no longer organized as a superlattice.

  14. Refractory Behaviors of Magnetite-Kaolin Bricks

    Science.gov (United States)

    Adeosun, S. O.; Akpan, E. I.; Gbenebor, O. P.; Taiwo, O. O.; Eke, I. J.

    2016-11-01

    In this work, the suitability of using kaolin-magnetite-plastic clay to produce refractory bricks has been experimentally explored. Thirty bricks of different compositions were produced and fired at 1200°C. The density, shrinkage moisture content, loss on ignition, porosity and permeability of the bricks were examined. Results show that the bricks remained stable during firing and thus possess good insulating characteristics. The highest (2.23 g/cm3) and lowest (2.00 g/cm3) bulk densities obtained in this study are higher than the highest bulk density reported for Al dross-filled refractories (1.23 g/cm3). The bricks also possessed very low effective moisture content (10-23%) and very high compression modulus (16-100 MPa) desirable in insulating refractory bricks with high resistance to abrasion.

  15. Dramatic response to infliximab in refractory neurosarcoidosis

    Directory of Open Access Journals (Sweden)

    Chintamaneni Sreekanth

    2010-01-01

    Full Text Available Sarcoidosis is a systemic disease characterized by noncaseating granulomas in the involved organs. Neurologic manifestations involving the central and/or peripheral nervous system occur in about 5% of patients. Neurosarcoidosis is often refractory to conventional treatment and therefore more effective treatment options are needed. While the etiology of the disease is still unknown, there is now a better understanding of its pathogenesis on a molecular level. It is clear that tumor necrosis factor-α (TNFα plays a pivotal role in the development of the granulomas and it is believed to be a key cytokine involved in the pathogenesis of the disease. Taking advantage of this better understanding of disease pathogenesis, anti-TNFα agents are being increasingly used to treat refractory sarcoidosis. We report a patient with refractory neurosarcoidosis who showed dramatic improvement in the clinical and radiological manifestations following treatment with infliximab; he suffered a relapse upon discontinuation of the medication.

  16. Topical cidofovir for refractory verrucae in children.

    Science.gov (United States)

    Gupta, Monique; Bayliss, Susan J; Berk, David R

    2013-01-01

    Warts are common and are a challenge to treat in some children, especially immunocompromised children and those who fail or cannot tolerate salicylic acid preparations and cryotherapy. Cidofovir, a nucleotide analogue with antiviral activity, has demonstrated promising results when compounded into a topical form to treat refractory warts. We present a retrospective institutional review of 12 children with refractory verrucae treated with 1% to 3% topical cidofovir compounded in an unscented moisturizing cream, applied every other day to daily. In our institutional series, only three patients (25%) demonstrated complete clearance of their verrucae. An additional four patients (33%) demonstrated partial clearance. Our experience using topical cidofovir has been less successful than previous institutional reviews, possibly because we used a lower concentration and less-frequent dosing. More studies are needed to better characterize the efficacy, safety, and dosing of topical cidofovir for the treatment of refractory warts.

  17. Office Procedures in Refractory Chronic Rhinosinusitis.

    Science.gov (United States)

    Thamboo, Andrew; Patel, Zara M

    2017-02-01

    Office procedures in chronic rhinosinusitis (CRS) can be considered before and after medical management, as well as before and after surgical management. This article focuses specifically on refractory CRS, meaning those patients who have failed medical and surgical management already. The options available in the management of refractory CRS depend on the personnel, equipment, and instrumentation available in the office setting; surgeon experience; and patient suitability and tolerability. This article provides readers with possible procedural options that can be done in their clinics with indications, patient selection, potential complications, and postoperative considerations.

  18. Effects of Boron Bearing Additives on Oxidation and Corrosion Resistance of Doloma—based carbon bonded Refractories

    Institute of Scientific and Technical Information of China (English)

    YEFangbao; ZHONGXiangchong; 等

    1998-01-01

    Oxidation of the added graphite and the bonding carbon is an imortant degradation mode of doloma-carbon refractories in service,In this work,the behavior and effects of various boron bearing materials(CaB6,ZrB2,Bc and colemanite)as an-tioxidants have been investigated and compared to the effect of Al-Mg alloy,For CaO-MgO-C mate-rials,the effect of boron bearingadditives is better than Al-Mg alloy,The borate melt formed at high temperature would retard or prevent carbon oxidation,thus contributing to improved oxidation resistance,Preliminary investigations on the effect of boron bearing additives and Al-Mg alloy on corrosion resistance of doloma-carbon materials have indicated that simultaneous addition of the two types of additives would lead to pronounced improvement of slag corrosion resistance.

  19. High-temperature deformation of L12-FCC two-phase Ir-15Nb-Ni refractory superalloys

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The creep behaviors of the Ni-added Ir 85Nb15 alloys were investigated at 1 650~1 800 ℃ by compressi on tests in vacuum. X-ray diffractometry, transmission electron microscopy and scanning electron microscopy were conducted to characterize the microstructure and lattice misfit change by the addition of Ni in the Ir85Nb15 alloy. The results reveal that the Ni addition has a significant effect on the creep resistance of the Ir85Nb15 two-phase refractory superal loys. Basing on the results, the relationship among the Ni addition, lattice mis fit, microstructure development, and the creep behavior in the Ni-added Ir8 5Nb15 alloys is discussed.

  20. Electrodeposition of Tantalum and Tantalum-Chromium Alloys

    Science.gov (United States)

    1980-05-01

    authors wish to acknowledge Mrs. Theresa Brassard and Mr. Joe Barranco for preparing micrographs of the specimens and microhardness measure- ments, and...Ahmad, P. Greco, G. D’Andrea, J. Barranco , "Potential Erosion Resistant Refractory Metal (And/Or) Alloy Coatings for Gun Tubes," Proceedings 1978...U.S. Patent 344058 (1969), Canadian Patent 688546 (1963). 17 REFERENCES 1. I. Ahmad, P. Greco, G. D’Andrea, and J. Barranco , "Potential Erosion

  1. Refractory Materials for Flame Deflector Protection System Corrosion Control: Refractory Ceramics Literature Survey

    Science.gov (United States)

    Calle, Luz Marina; Hintze, Paul E.; Parlier, Christopher R.; Curran, Jerome P.; Kolody, Mark; Perusich, Stephen; Whitten, Mary C.; Trejo, David; Zidek, Jason; Sampson, Jeffrey W.; Coffman, Brekke E.

    2009-01-01

    Ceramics can be defmed as a material consisting of hard brittle properties produced from inorganic and nonmetallic minerals made by firing at high temperatures. These materials are compounds between metallic and nonmetallic elements and are either totally ionic, or predominately ionic but having some covalent character. This definition allows for a large range of materials, not all applicable to refractory applications. As this report is focused on potential ceramic materials for high temperature, aggressive exposure applications, the ceramics reviewed as part of this report will focus on refractory ceramics specifically designed and used for these applications. Ceramic materials consist of a wide variety of products. Callister (2000) 1 characterized ceramic materials into six classifications: glasses, clay products, refractories, cements, abrasives, and advanced ceramics. Figure 1 shows this classification system. This review will focus mainly on refractory ceramics and cements as in general, the other classifications are neither applicable nor economical for use in large structures such as the flame trench. Although much work has been done in advanced ceramics over the past decade or so, these materials are likely cost prohibitive and would have to be fabricated off-site, transported to the NASA facilities, and installed, which make these even less feasible. Although the authors reviewed the literature on advanced ceramic refractories 2 center dot 3 center dot 4 center dot 5 center dot 6 center dot 7 center dot 8 center dot 9 center dot 10 center dot 11 center dot 12 after the review it was concluded that these materials should not be ' the focus of this report. A review is in progress on materials and systems for prefabricated refractory ceramic panels, but this review is focusing more on typical refractory materials for prefabricated systems, which could make the system more economically feasible. Refractory ceramics are used for a wide variety of applications

  2. Refractory disease in antineutrophil cytoplasmic antibodies associated vasculitis

    NARCIS (Netherlands)

    Rutgers, Abraham; Kallenberg, Cornelis

    2012-01-01

    Purpose of review Induction treatment of antineutrophil cytoplasmic antibodies (ANCA) associated vasculitis (AAV) is not always successful and nonresponding patients are considered refractory. Recent findings Refractory disease should be subdefined to the treatment that was received. Cyclophosphamid

  3. Recent advances in silica-alumina refractory: A review

    Directory of Open Access Journals (Sweden)

    Chaouki Sadik

    2014-06-01

    Full Text Available In this article, the elaboration and the characterization of silica-alumina refractory have been reviewed. Refractory oxides encompass a broad range of unary, binary, and ternary ceramic compounds that can be used in structural, insulating, and other applications. This paper provides a historical perspective on the elaboration and the use of silica-alumina refractory, reviews applications for refractory oxides, describes typical processing routes, overviews fundamental structure–property relations, and summarizes the properties of these materials.

  4. Tungsten and other refractory metals for VLSI applications II

    Energy Technology Data Exchange (ETDEWEB)

    Broadbent, E.K.

    1987-01-01

    This book presents papers on tungsten and other refractory metals for VLSI applications. Topics include the following: Selectivity loss and nucleation on insulators, fundamental reaction and growth studies, chemical vapor deposition of tungsten, chemical vapor deposition of molybdenum, reactive ion etching of refractory metal films; and properties of refractory metals deposited by sputtering.

  5. An Overview on China's Refractories-Market and New Demands

    Institute of Scientific and Technical Information of China (English)

    LIU Jiehua; ZHOU Ningsheng

    2004-01-01

    Based on the authors' information sources and personal viewpoints, this paper provides updated information on China s refractories situation in terms of output, consumption in main refractory using sectors, exportation and importation of refractory products and raw materials,structural change, future prosperity and new demands .From authors understanding, some analyses have also been given.

  6. Export and Import Situation of Refractories in China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    China has been the biggest country in production and exporting of refractories. The article describes the problems in the export and import and suggestions on development of refractories. In the future, China will expand its cooperation with world refractories community in science, technology, economy and trade to play a more important role in the international and domestic markets.

  7. Management of refractory ischemic priapism: current perspectives.

    Science.gov (United States)

    Capece, Marco; Gillo, Arianna; Cocci, Andrea; Garaffa, Giulio; Timpano, Massimiliano; Falcone, Marco

    2017-01-01

    The aim of the present manuscript is to review the current literature on priapism, focusing on the state-of-the-art knowledge of both the diagnosis and the treatment of the refractory ischemic priapism (IP). Pubmed and EMBASE search engines were used to search for words "priapism", "refractory priapism", "penile prosthesis", "diagnosis priapism", "priapism treatment", "penile fibrosis", "priapism therapy". All the studies were carefully examined by the authors and then included in the review. First-line treatment involves ejaculation, physical exercise and cold shower followed by corporal blood aspiration and injection of α-adrenoceptor agonists. Subsequently, a distal or proximal shunt may be considered. If none of the treatment is effective or the priapism episode lasts >48 hours penile prosthesis implantation could be the only option to solve the priapism and treat the ongoing erectile dysfunction. The management of IP is to achieve detumescence of persistent penile erection and to preserve erectile function after resolution of the priapic episode. On the other hand, penile fibrosis and following shortening should be prevented. Early penile prosthesis implantation in patients with refractory IP is able to solve both the priapic episode and prevent the otherwise certain penile shortening. Penile prosthesis implantation is the actual gold standard of care in cases of refractory IP.

  8. Synthetic Raw Materials for Refractories in China

    Institute of Scientific and Technical Information of China (English)

    SHIGan; YUEWeidong

    2001-01-01

    The development and status of synthetic raw materials for refractories in China are reviewed,including magne-site-based materials,alumina ,ullite,calcium alumi-nate cement ,ultrafine powder,spinel,silicon carbide and cordierite.The research work on calcium zirconate and sialon materials are also introduced.

  9. Increasing the reliability and quality of important cast products made of chemically active metals and alloys

    Science.gov (United States)

    Varfolomeev, M. S.; Moiseev, V. S.; Shcherbakova, G. I.

    2017-01-01

    A technology is developed to produce highly thermoresistant ceramic monoxide corundum molds using investment casting and an aluminum-organic binder. This technology is a promising trend in creating ceramic molds for precision complex-shape casting of important ingots made of high-alloy steels, high-temperature and titanium alloys, and refractory metals. The use of the casting molds that have a high thermal and chemical resistance to chemically active metals and alloys under high-temperature casting minimizes the physicochemical interaction and substantially decreases the depth of the hard-to-remove metal oxide layer on important products, which increases their service properties.

  10. Microstructures and oxidation behavior of some Molybdenum based alloys

    Energy Technology Data Exchange (ETDEWEB)

    Ray, Pratik Kumar [Iowa State Univ., Ames, IA (United States)

    2011-01-01

    The advent of Ni based superalloys revolutionized the high temperature alloy industry. These materials are capable of operating in extremely harsh environments, comprising of temperatures around 1050 C, under oxidative conditions. Demands for increased fuel efficiency, however, has highlighted the need for materials that can be used under oxidative conditions at temperatures in excess of 1200 C. The Ni based superalloys are restricted to lower temperatures due to the presence of a number of low melting phases that melt in the 1250 - 1450 C, resulting in softening of the alloys above 1000 C. Therefore, recent research directions have been skewed towards exploring and developing newer alloy systems. This thesis comprises a part of such an effort. Techniques for rapid thermodynamic assessments were developed and applied to two different systems - Mo-Si alloys with transition metal substitutions (and this forms the first part of the thesis) and Ni-Al alloys with added components for providing high temperature strength and ductility. A hierarchical approach towards alloy design indicated the Mo-Ni-Al system as a prospective candidate for high temperature applications. Investigations on microstructures and oxidation behavior, under both isothermal and cyclic conditions, of these alloys constitute the second part of this thesis. It was seen that refractory metal systems show a marked microstructure dependence of oxidation.

  11. 2011 China's Refractories Raw Materials Symposium Held in Zhengzhou

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    @@ On April 20-22,2011,China's Refractories Raw Materials Symposium,co-sponsored by Refractories Branch of The Chinese Society for Metals and China Henan Refractory Industry Association,was held successfully in Zhengzhou,Henan Province.Over 150 delegates from 100 refractory raw materials and products enterprises,testing equipment manufacturers,raw materials trade companies,institutes,universities,testing institutions,and industrial organizations attended the symposium.Wang Shouye,secretary-general of Refractories Branch of The Chinese Society for Metals and vice president of Sinosteel Luoyang Institute of Refractories Research Co.,Ltd.,made the address of welcome.Zhang Yazhong,vice chairman of Henan Committee of the Chinese People's Political Consultative Conference and honorary chairman of China Henan Refractory Industry Association,gave a speech.

  12. Improved Refractories for IGCC Power Systems

    Energy Technology Data Exchange (ETDEWEB)

    Dogan, Cynthia P.; Kwong, Kyei-Sing; Bennett, James P.; Chinn, Richard E.; Dahlin, Cheryl L.

    2002-01-01

    The gasification of coal, petroleum residuals, and biomass provides the opportunity to produce energy more efficiently, and with significantly less environmental impact, than more-conventional combustion-based processes. In addition, the synthesis gas that is the product of the gasification process offers the gasifier operator the option of ''polygeneration'', i.e., the production of alternative products instead of power should it be economically favorable to do so. Because of these advantages, gasification is a key element in the U.S. Department of Energy?s Vision 21 power system. However, issues with both the reliability and the economics of gasifier operation will have to be resolved before gasification will be widely adopted by the power industry. Central to both increased reliability and economics is the development of materials with longer service lives in gasifier systems that can provide extended periods of continuous gasifier operation. The focus of the Advanced Refractories for Gasification project at the Albany Research Center is to develop improved materials capable of withstanding the harsh, high-temperature environment created by the gasification reaction, and includes both the refractory lining that insulates the slagging gasifier, as well as the thermocouple assemblies that are utilized to monitor gasifier operating temperatures. Current generation refractory liners in slagging gasifiers are typically replaced every 10 to 18 months, at costs ranging up to $2,000,000. Compounding materials and installation costs are the lost-opportunity costs for the three to four weeks that the gasifier is off-line for the refractory exchange. Current generation thermocouple devices rarely survive the gasifier start-up process, leaving the operator with no real means of temperature measurement during gasifier operation. As a result, the goals of this project include the development of a refractory liner with a service life at least double that of

  13. Stress corrosion cracking of titanium alloys

    Science.gov (United States)

    Statler, G. R.; Spretnak, J. W.; Beck, F. H.; Fontana, M. G.

    1974-01-01

    The effect of hydrogen on the properties of metals, including titanium and its alloys, was investigated. The basic theories of stress corrosion of titanium alloys are reviewed along with the literature concerned with the effect of absorbed hydrogen on the mechanical properties of metals. Finally, the basic modes of metal fracture and their importance to this study is considered. The experimental work was designed to determine the effects of hydrogen concentration on the critical strain at which plastic instability along pure shear directions occurs. The materials used were titanium alloys Ti-8Al-lMo-lV and Ti-5Al-2.5Sn.

  14. Zirconium alloys produced by recycling zircaloy tunings

    Energy Technology Data Exchange (ETDEWEB)

    Gamba, N.S. [Instituto de Investigaciones en Catálisis y Petroquímica, INCAPE (FIQ, UNL–CONICET), Santiago del Estero 2829, 3000 Santa Fe (Argentina); Carbajal-Ramos, I.A. [Centro Atómico Bariloche, CNEA e Instituto Balseiro, Universidad Nacional de Cuyo, Av. Bustillo 9500, 8400 Bariloche (Argentina); Ulla, M.A.; Pierini, B.T. [Instituto de Investigaciones en Catálisis y Petroquímica, INCAPE (FIQ, UNL–CONICET), Santiago del Estero 2829, 3000 Santa Fe (Argentina); Gennari, F.C., E-mail: gennari@cab.cnea.gov.ar [Centro Atómico Bariloche, CNEA e Instituto Balseiro, Universidad Nacional de Cuyo, Av. Bustillo 9500, 8400 Bariloche (Argentina)

    2013-11-25

    Highlights: •Zr–Ti alloys were successfully produced by two-step procedure. •Zircaloy tunings were used as a valuable source of Zr. •Zircaloy tunings and Ti powders was milled under hydrogen to produce hydride powders. •Hydride powders were decomposed by heating at 900 °C to synthesize the Zr-based alloy. •The procedure could be extended to the production of other Zr-based alloys. -- Abstract: Zircaloy chips were recycled to successfully produce Zr–Ti alloys with bcc structure and different compositions. The procedure developed involves two steps. First, the reactive mechanical alloying (RMA) of the zircaloy tunings and Ti powders was performed to produce metal hydride powders, with a high refinement of the microstructure and a Zr–Ti homogeneous composition. Second, the metal hydride powders were thermally decomposed by heating up to 900 °C to synthesize the Zr-based alloy with a selected composition. The change in the nature of the powders from ductile to brittle during milling avoids both cold working phenomena between the metals and the use of a control agent. A minimum milling time is necessary to produce the solid solution with the selected composition. The microstructure and structure of the final alloys obtained was studied. The present procedure could be extended to the production of Zr-based alloys with the addition of other metals different from Ti.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-02-06

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

  16. Midazolam and pentobarbital for refractory status epilepticus.

    Science.gov (United States)

    Holmes, G L; Riviello, J J

    1999-04-01

    Status epilepticus, a serious, life-threatening emergency characterized by prolonged seizure activity, occurs most commonly in pediatric patients. Although initial therapies with agents such as diazepam, phenytoin, or phenobarbital generally terminate seizure activity within 30-60 minutes, patients with refractory status epilepticus (RSE) lasting longer require additional intervention. High-dose pentobarbital has been the most commonly prescribed agent for the management of RSE in children; however, midazolam has emerged as a new treatment option. This review compares the use of midazolam with pentobarbital in published reports of pediatric RSE. Both drugs effectively terminated refractory seizure activity, although pentobarbital use was complicated by hypotension, delayed recovery, pneumonia, and other adverse effects. Midazolam use was effective and well tolerated, affirming its value in pediatric RSE management.

  17. EXTRASOLAR REFRACTORY-DOMINATED PLANETESIMALS: AN ASSESSMENT

    Energy Technology Data Exchange (ETDEWEB)

    Jura, M.; Xu, S., E-mail: jura@astro.ucla.edu, E-mail: sxu@astro.ucla.edu [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095-1562 (United States)

    2013-02-01

    Previously published observations of 60 externally polluted white dwarfs show that none of the stars have accreted from intact refractory-dominated parent bodies composed mainly of Al, Ca, and O, although planetesimals with such a distinctive composition have been predicted to form. We propose that such remarkable objects are not detected by themselves because, unless they are scattered outward from their initial orbit, they are engulfed and destroyed during the star's asymptotic giant branch evolution. As yet, there is at most only weak evidence supporting a scenario where the composition of any extrasolar minor planet can be explained by blending of an outwardly scattered refractory-dominated planetesimal with an ambient asteroid.

  18. [Liposteroid therapy for refractory epileptic spasms].

    Science.gov (United States)

    Shimono, Kuriko Kagitani; Imai, Katsumi; Idoguchi, Rie; Kamio, Noriko; Okinaga, Takeshi; Ozono, Keiichi

    2003-11-01

    Liposteroid was administered intravenously to 6 patients with refractory epileptic spasms. In one case, the spasms initially disappeared but then reappeared after three months. Another case had a transient and slight decrease of epileptic spasms. In the only patient in whom spasms disappeared, EEG abnormalities were greatly improved with diffuse spikes and waves changing into focal spikes. Two cases displayed hyperexcitability, insomnia and acting out behavior, and the therapy was discontinued in one of them. One case had appetite loss and another showed an increase in tonic seizures. No patient had serious adverse effects such as infection, edema, subdural hematoma and brain shrinkage. Although liposteroid therapy has been recommended as an easy, useful and safe alternative for ACTH, we found considerable adverse effects and only a small effect on refractory spasms, and conclude that the regimen should be modified.

  19. Arrhythmogenic channelopathy syndromes presenting as refractory epilepsy.

    Science.gov (United States)

    Hazle, Matthew A; Shellhaas, Renée A; Bradley, David J; Dick, Macdonald; Lapage, Martin J

    2013-08-01

    Children and young adults with potentially lethal cardiac channelopathies often present to medical care with a history of syncope or seizures due to episodic ventricular arrhythmias and associated cerebral hypoperfusion. Two important types of genetic arrhythmia syndromes-long QT syndrome and catecholaminergic polymorphic ventricular tachycardia-are discussed using relevant case examples. The pathophysiology and distinguishing clinical features of these conditions are reviewed. The patients in each case were ultimately diagnosed with a cardiac channelopathy as the cause for their syncope and refractory seizures. With appropriate medical management, no further events have occurred to date. Cardiac channelopathies can be misdiagnosed as refractory epilepsy when in fact these events represent convulsive syncopes. Knowledge of and suspicion for these arrhythmogenic conditions may expedite diagnosis and improve outcomes. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Molecular sidebands of refractory elements for ISOL

    Energy Technology Data Exchange (ETDEWEB)

    Kronenberg, A. [Oak Ridge Associated Universities, Oak Ridge (United States)], E-mail: kronenberga@ornl.gov; Spejewski, E.H.; Carter, H.K.; Mervin, B.; Jost, C. [Oak Ridge Associated Universities, Oak Ridge (United States); Stracener, D.W. [Oak Ridge National Laboratory, TN 37831 (United States); Lapi, S. [TRIUMF (Canada); Bray, T. [Auburn University (United States)

    2008-10-15

    The formation of molecular sidebands of refractory elements, such as V, Re, Zr, Mo, Tc, is discussed. The focus is on in situ sideband formation and its advantage for the release process. An atomic {sup 48}V beam has been produced in a two step process, forming the oxide in situ, transporting it through the target-ion source as a chloride and destroying the chlorine sideband in the ion source. The sideband formation of Re, Zr, Mo, Tc is discussed.

  1. Molecular Sidebands of Refractory Elements for ISOL

    Energy Technology Data Exchange (ETDEWEB)

    Kronenberg, Andreas [Oak Ridge Associated Universities (ORAU); Spejewski, Eugene H. [Oak Ridge Associated Universities (ORAU); Carter, H Kennon [Oak Ridge Associated Universities (ORAU); Mervin, Brenden T. [Oak Ridge Associated Universities (ORAU); Jost, Cara [Oak Ridge Associated Universities (ORAU); Stracener, Daniel W [ORNL; Lapi, Suzanne [TRIUMF, Canada; Bray, T. H. [Auburn University, Auburn, Alabama

    2008-01-01

    The formation of molecular sidebands of refractory elements, such as V, Re, Zr, Mo, Tc, is discussed. The focus is on in situ sideband formation and its advantage for the release process. An atomic 48V beam has been produced in a two step process, forming the oxide in situ, transporting it through the target-ion source as a chloride and destroying the chlorine sideband in the ion source. The sideband formation of Re, Zr, Mo, Tc is discussed.

  2. Extracorporeal life support for refractory ventricular tachycardia

    Science.gov (United States)

    Joseph, Nicholas; Hofmann, James P.; Saranteas, Theodosios; Papadimos, Thomas J.

    2017-01-01

    Extracorporeal life support (ECLS) is a very effective bridging therapy in patients with refractory ventricular tachycardia (VT) associated with cardiogenic shock. A moribund patient in extremis, is not amenable to optimization by standard ACC/AHA guidelines. New approaches and novel salvage techniques are necessary to improve outcomes in patients with refractory clinical settings such as malignant ventricular arrhythmias, cardiac arrest, cardiogenic shock and/or pulmonary failure until further management options are explored. Data base searches were done using key words such as ECLS, VT, cardiac arrest, VT ablation, venoarterial extra-corporeal membrane oxygenation (VA-ECMO). The use of ECLS has been described in a few case reports to facilitate VT ablation for incessant VT refractory to medical therapy. For patients with, out-of- hospital ventricular fibrillation (VF) and VT, Minnesota Resuscitation Consortium has implemented emergent advanced perfusion and reperfusion strategy, followed by coronary angiography and primary coronary intervention to improve outcome. The major indications for ECLS are cardiogenic shock related to acute myocardial infarction, myocarditis, post embolic acute cor pulmonale, drug intoxication and post cardiac arrest syndrome with the threat of multi-organ failure. ECLS permits the use of negative inotropic antiarrhythmic drug therapy, facilitates the weaning of catecholamine administration, thereby ending the vicious cycle of catecholamine driven electric storm. ECLS provides hemodynamic support during ablation procedure, while mapping and induction of VT is undertaken. ECLS provides early access to cardiac catheterization laboratory in patients with cardiac arrest due to shockable rhythm. The current evidence from literature, supports the use of ECLS to ensure adequate vital organ perfusion in patients with refractory VT. ECLS is a safe, feasible and effective therapeutic option when conventional therapies are insufficient to support

  3. Management of refractory ischemic priapism: current perspectives

    Directory of Open Access Journals (Sweden)

    Capece M

    2017-08-01

    Full Text Available Marco Capece,1 Arianna Gillo,2 Andrea Cocci,3 Giulio Garaffa,1 Massimiliano Timpano,4 Marco Falcone4 1The Institute of Urology, University College of London Hospital (UCLH, London, UK; 2Department of Urology, “Umberto Parini” Hospital, Aosta, 3Department of Urology, Careggi Hospital, Firenze, 4Department of Urology, University of Turin, Città della Salute e della Scienza, Turin, Italy Objectives: The aim of the present manuscript is to review the current literature on priapism, focusing on the state-of-the-art knowledge of both the diagnosis and the treatment of the refractory ischemic priapism (IP.Methods: Pubmed and EMBASE search engines were used to search for words “priapism”, “refractory priapism”, “penile prosthesis”, “diagnosis priapism”, “priapism treatment”, “penile fibrosis”, “priapism therapy”. All the studies were carefully examined by the authors and then included in the review.Results: First-line treatment involves ejaculation, physical exercise and cold shower followed by corporal blood aspiration and injection of α-adrenoceptor agonists. Subsequently, a distal or proximal shunt may be considered. If none of the treatment is effective or the priapism episode lasts >48 hours penile prosthesis implantation could be the only option to solve the priapism and treat the ongoing erectile dysfunction.Conclusion: The management of IP is to achieve detumescence of persistent penile erection and to preserve erectile function after resolution of the priapic episode. On the other hand, penile fibrosis and following shortening should be prevented. Early penile prosthesis implantation in patients with refractory IP is able to solve both the priapic episode and prevent the otherwise certain penile shortening. Penile prosthesis implantation is the actual gold standard of care in cases of refractory IP. Keywords: priapism, ischemic priapism, penile fibrosis, penile prosthesis, shunt 

  4. Propofol infusion syndrome in refractory status epilepticus.

    Science.gov (United States)

    Hwang, Woo Sub; Gwak, Hye Min; Seo, Dae-Won

    2013-06-01

    Propofol is used for treating refractory status epilepticus, which has high rate of mortality. Propofol infusion syndrome is a rare but often fatal syndrome, characterized by lactic acidosis, lipidemia, and cardiac failure, associated with propofol infusion over prolonged periods of time. We investigated the clinical factors that characterize propofol infusion syndrome to know the risk of them in refractory status epilepticus. This retrospective observation study was conducted in Samsung medical center from Jan. 2005 to Dec. 2009. Thirty two patients (19 males, 13 females, aged between 16 and 64 years), with refractory status epilepsy were included. Their clinical findings and treatment outcomes were evaluated retrospectively. We divided our patients into established status epilepticus (ESE) and refractory status epilepticus (RSE). And then the patients with RSE was further subdivided into propofol treatment group (RSE-P) and the other anesthetics treatment group (RSE-O). We analyzed the clinical characteristics by comparison of the groups. There were significant differences of hypotension and lipid change between ESE and RSE (pRSE-P and RSE-O groups. The hospital days were longer in RSE than in ESE (p=0.012) and treatment outcome was also worse in RSE than in ESE (p=0.007) but there were no significant differences of hospital stays and treatment outcome between RSE-P and RSE-O. RSE is very critical disease with high mortality, which may show as many clinical changes as propofol infusion syndrome. Therefore propofol infusion syndrome might be considered as one of the clinical manifestations of RSE.

  5. Review of the United States Refractories Industry

    Institute of Scientific and Technical Information of China (English)

    Charles E.Semler

    2003-01-01

    Factors affecting the U. S. Refractories industry,such us decreasing demand, mergers, and decreased education are discussed, along with manufacturing statistics (I. E., annual value and product trends ), indicating that the U. S. Market has declined for five straight years.Research activities have changed, with more emphasis on practical, applied projects, which have continued to produce important advances. Many challenges and opportunities remain, based on the current and future business requirements.

  6. Experimental Design for Evaluation of Co-extruded Refractory Metal/Nickel Base Superalloy Joints

    Energy Technology Data Exchange (ETDEWEB)

    ME Petrichek

    2005-12-16

    Prior to the restructuring of the Prometheus Program, the NRPCT was tasked with delivering a nuclear space reactor. Potential NRPCT nuclear space reactor designs for the Prometheus Project required dissimilar materials to be in contact with each other while operating at extreme temperatures under irradiation. As a result of the high reactor core temperatures, refractory metals were the primary candidates for many of the reactor structural and cladding components. They included the tantalum-base alloys ASTAR-811C and Ta-10W, the niobium-base alloy FS-85, and the molybdenum base alloys Moly 41-47.5 Rhenium. The refractory metals were to be joined to candidate nickel base alloys such as Haynes 230, Alloy 617, or Nimonic PE 16 either within the core if the nickel-base alloys were ultimately selected to form the outer core barrel, or at a location exterior to the core if the nickel-base alloys were limited to components exterior to the core. To support the need for dissimilar metal joints in the Prometheus Project, a co-extrusion experiment was proposed. There are several potential methods for the formation of dissimilar metal joints, including explosive bonding, friction stir welding, plasma spray, inertia welding, HIP, and co-extrusion. Most of these joining methods are not viable options because they result in the immediate formation of brittle intermetallics. Upon cooling, intermetallics form in the weld fusion zone between the joined metals. Because brittle intermetallics do not form during the initial bonding process associated with HIP, co-extrusion, and explosive bonding, these three joining procedures are preferred for forming dissimilar metal joints. In reference to a Westinghouse Astronuclear Laboratory report done under a NASA sponsored program, joints that were fabricated between similar materials via explosive bonding had strengths that were directly affected by the width of the diffusion barrier. It was determined that the diffusion zone should not exceed

  7. Predicting factors for refractory kawasaki disease.

    Science.gov (United States)

    Do, Young-Sun; Kim, Ki-Won; Chun, Jin-Kyong; Cha, Byung Ho; Namgoong, Mee Kyung; Lee, Hae Yong

    2010-05-01

    About 10-15% of Kawasaki disease (KD) is refractory to intravenous immunoglobulin (IVIG) therapy. This study was designed to investigate the predicting factors for refractory KD. We reviewed retrospectively the clinical records of 77 patients with typical KD admitted at Wonju Christian Hospital from January, 2005, to December, 2008. The variance of laboratory and demographic parameters between the IVIG-responsive group and IVIG-resistant group were analyzed. Thirteen patients with urinary tract infections were randomly collected as a febrile control group. Among 77 patients diagnosed with complete KD, 13 patients (16.9%) were IVIG-resistant. The febrile period and hospital days were significantly longer in the IVIG-resistant group than IVIG-responsive group (pIVIG-resistant group (p=0.025). The Kobayashi score could differentiate these two groups (p=0.015). Fewer lymphocytes was observed during the subacute phase in the IVIG-resistant group (p=0.032). Coronary arterial dilatations (CADs) were observed in 10.9% (7/64) of IVIG-responders and 38.5% (5/13) of IVIG-resistant patients (p=0.038). The percentage of neutrophils and lymphocytes in patients with KD, in addition to known risk factors for refractory KD, may help predict IVIG-resistance in patients with KD.

  8. New-onset refractory status epilepticus

    Science.gov (United States)

    Foreman, Brandon P.; Alvarez, Vincent; Cabrera Kang, Christian; Probasco, John C.; Jongeling, Amy C.; Meyers, Emma; Espinera, Alyssa; Haas, Kevin F.; Schmitt, Sarah E.; Gerard, Elizabeth E.; Gofton, Teneille; Kaplan, Peter W.; Lee, Jong W.; Legros, Benjamin; Szaflarski, Jerzy P.; Westover, Brandon M.; LaRoche, Suzette M.; Hirsch, Lawrence J.

    2015-01-01

    Objectives: The aims of this study were to determine the etiology, clinical features, and predictors of outcome of new-onset refractory status epilepticus. Methods: Retrospective review of patients with refractory status epilepticus without etiology identified within 48 hours of admission between January 1, 2008, and December 31, 2013, in 13 academic medical centers. The primary outcome measure was poor functional outcome at discharge (defined as a score >3 on the modified Rankin Scale). Results: Of 130 cases, 67 (52%) remained cryptogenic. The most common identified etiologies were autoimmune (19%) and paraneoplastic (18%) encephalitis. Full data were available in 125 cases (62 cryptogenic). Poor outcome occurred in 77 of 125 cases (62%), and 28 (22%) died. Predictors of poor outcome included duration of status epilepticus, use of anesthetics, and medical complications. Among the 63 patients with available follow-up data (median 9 months), functional status improved in 36 (57%); 79% had good or fair outcome at last follow-up, but epilepsy developed in 37% with most survivors (92%) remaining on antiseizure medications. Immune therapies were used less frequently in cryptogenic cases, despite a comparable prevalence of inflammatory CSF changes. Conclusions: Autoimmune encephalitis is the most commonly identified cause of new-onset refractory status epilepticus, but half remain cryptogenic. Outcome at discharge is poor but improves during follow-up. Epilepsy develops in most cases. The role of anesthetics and immune therapies warrants further investigation. PMID:26296517

  9. Posaconazole treatment of refractory eumycetoma and chromoblastomycosis.

    Science.gov (United States)

    Negroni, Ricardo; Tobón, Angela; Bustamante, Beatriz; Shikanai-Yasuda, Maria Aparecida; Patino, Hernando; Restrepo, Angela

    2005-01-01

    Eumycetoma and chromoblastomycosis are chronic, disfiguring fungal infections of the subcutaneous tissue that rarely resolve spontaneously. Most patients do not achieve sustained long-term benefits from available treatments; therefore, new therapeutic options are needed. We evaluated the efficacy of posaconazole, a new extended-spectrum triazole antifungal agent, in 12 patients with eumycetoma or chromoblastomycosis refractory to existing antifungal therapies. Posaconazole 800 mg/d was given in divided doses for a maximum of 34 months. Complete or partial clinical response was considered a success; stable disease or failure was considered a nonsuccess. All 12 patients had proven infections refractory to standard therapy. Clinical success was reported for five of six patients with eumycetoma and five of six patients with chromoblastomycosis. Two patients were reported to have stable disease. As part of a treatment-use extension protocol, two patients with eumycetoma who initially had successful outcome were successfully retreated with posaconazole after a treatment hiatus of > 10 months. Posaconazole was well tolerated during long-term administration (up to 1015 d). Posaconazole therapy resulted in successful outcome in most patients with eumycetoma or chromoblastomycosis refractory to standard therapies, suggesting that posaconazole may be an important treatment option for these diseases.

  10. Angiotensin II in Refractory Septic Shock.

    Science.gov (United States)

    Antonucci, Elio; Gleeson, Patrick J; Annoni, Filippo; Agosta, Sara; Orlando, Sergio; Taccone, Fabio Silvio; Velissaris, Dimitrios; Scolletta, Sabino

    2017-05-01

    Refractory septic shock is defined as persistently low mean arterial blood pressure despite volume resuscitation and titrated vasopressors/inotropes in patients with a proven or suspected infection and concomitant organ dysfunction. Its management typically requires high doses of catecholamines, which can induce significant adverse effects such as ischemia and arrhythmias. Angiotensin II (Ang II), a key product of the renin-angiotensin-aldosterone system, is a vasopressor agent that could be used in conjunction with other vasopressors to stabilize critically ill patients during refractory septic shock, and reduce catecholamine requirements. However, very few clinical data are available to support Ang II administration in this setting. Here, we review the current literature on this topic to better understand the role of Ang II administration during refractory septic shock, differentiating experimental from clinical studies. We also consider the potential role of exogenous Ang II administration in specific organ dysfunction and possible pitfalls with Ang II in sepsis. Various issues remain unresolved and future studies should investigate important topics such as: the optimal dose and timing of Ang II administration, a comparison between Ang II and the other vasopressors (epinephrine; vasopressin), and Ang II effects on microcirculation.

  11. Refractory status epilepticus: a prospective observational study.

    Science.gov (United States)

    Novy, Jan; Logroscino, Giancarlo; Rossetti, Andrea O

    2010-02-01

    Status epilepticus (SE) that is resistant to two antiepileptic compounds is defined as refractory status epilepticus (RSE). In the few available retrospective studies, estimated RSE frequency is between 31% and 43% of patients presenting an SE episode; almost all seem to require a coma induction for treatment. We prospectively assessed RSE frequency, clinical predictors, and outcome in a tertiary clinical setting. Over 2 years we collected 128 consecutive SE episodes (118 patients) in adults. Clinical data and their relationship to outcome (mortality and return to baseline clinical conditions) were analyzed. Twenty-nine of 128 SE episodes (22.6%) were refractory to first- and second-line antiepileptic treatments. Severity of consciousness impairment and de novo episodes were independent predictors of RSE. RSE showed a worse outcome than non-RSE (39% vs. 11% for mortality; 21% vs. 63% for return to baseline clinical conditions). Only 12 patients with RSE (41%) required coma induction for treatment. This prospective study identifies clinical factors predicting the onset of SE refractoriness. RSE appears to be less frequent than previously reported in retrospective studies; furthermore, most RSE episodes were treated outside the intensive care unit (ICU). Nonetheless, we confirm that RSE is characterized by high mortality and morbidity.

  12. [Renal replacement therapy for refractory heart failure].

    Science.gov (United States)

    Schwenger, V; Remppis, A B

    2012-07-01

    After broad cardiological and nephrological evaluation and consideration of optimal conservative options according to national and international guidelines, renal replacement therapy might be helpful in patients with refractory heart failure even if they are not dialysis-dependent. This is even more important as renal failure is a strong predictor for mortality in patients with severe congestive heart failure (CHF) and CHF is one of the fastest growing morbidities in western countries. Although peritoneal dialysis (PD) is frequently used in patients with CHF its role remains unclear. Acute chronic volume overload in refractory CHF is still an unresolved clinical problem. In patients with acute heart and renal failure with need of management in an intensive care unit, extracorporeal ultrafiltration or a dialysis modality should be preferred. In patients with chronic refractory CHF, volume overload and renal failure, peritoneal dialysis should be the therapy of choice. Due to the limited data available, treatment and outcome parameters should be recorded in the registry of the German Society of Nephrology (http://www.herz-niere.de).

  13. Tacrolimus Ointment for Refractory Posterior Blepharitis.

    Science.gov (United States)

    Sakassegawa-Naves, Fernando Eiji; Ricci, Helena Maria Moraes; Moscovici, Bernardo Kaplan; Miyamoto, Daniela Akemi; Chiacchio, Brenda Biagio; Holzchuh, Ricardo; Santo, Ruth Muyuki; Hida, Richard Yudi

    2017-09-18

    This prospective, randomized, double-blind interventional case series was designed to evaluate the short-term efficacy of 0.03% tacrolimus ointment as a new therapeutic approach for refractory cases of posterior blepharitis. Forty eyes (20 patients) with posterior blepharitis refractory to previous treatment were randomized. Eighteen eyes (9 patients) were treated with 0.03% tacrolimus ointment and 20 eyes (10 patients) with placebo ointment twice daily. Patients were evaluated with a questionnaire and slit-lamp examination 14 days and 28 days after treatment, and symptoms and signs of blepharitis were compared to those observed at baseline. We could observe statistical difference in the outcome measurements of meibomian gland secretion, conjunctival hyperemia, telangiectasia of inferior lid, Rose Bengal, and fluorescein scoring for the study group. As for the symptoms score, we observed statistical difference in the symptoms scoring for pruritus and dry eye sensation in the tacrolimus group. This study suggests that topical administration of 0.03% tacrolimus ointment can improve some symptoms and some ocular surface status in patients with refractory posterior blepharitis.

  14. MoNbTaV Medium-Entropy Alloy

    Directory of Open Access Journals (Sweden)

    Hongwei Yao

    2016-05-01

    Full Text Available Guided by CALPHAD (Calculation of Phase Diagrams modeling, the refractory medium-entropy alloy MoNbTaV was synthesized by vacuum arc melting under a high-purity argon atmosphere. A body-centered cubic solid solution phase was experimentally confirmed in the as-cast ingot using X-ray diffraction and scanning electron microscopy. The measured lattice parameter of the alloy (3.208 Å obeys the rule of mixtures (ROM, but the Vickers microhardness (4.95 GPa and the yield strength (1.5 GPa are about 4.5 and 4.6 times those estimated from the ROM, respectively. Using a simple model on solid solution strengthening predicts a yield strength of approximately 1.5 GPa. Thermodynamic analysis shows that the total entropy of the alloy is more than three times the configurational entropy at room temperature, and the entropy of mixing exhibits a small negative departure from ideal mixing.

  15. Meta-analysis of adjunctive levetiracetam in refractory partial sei

    Directory of Open Access Journals (Sweden)

    ZHANG Ying

    2012-10-01

    Full Text Available Objective To evaluate the effects and tolerability of adjunctive levetiracetam (LEV in refractory partial seizures. Methods Relevant research articles about randomized controlled trials of adjunctive LEV in refractory partial seizures from January 1998 to December 2010 were retrieved from Cochrane Library, MEDLINE, EMbase, Social Sciences Citation Index (SSCI, VIP, Chinese National Knowledge Infrastructure (CNKI database, China Biology Medicine (CBM. Two reviewers independently evaluated the quality of the included articles and abstracted the data. A Meta-analysis was conducted by using RevMan 5.0 software. Results According to the enrollment criteria, eleven prospective, randomized controlled clinical trials with a total of 1192 in LEV group and 789 in placebo group were finally selected. The reduction in three endpoints (a 50% or greater reduction of partial seizure frequency per week, a 75% or greater reduction of partial seizure frequency per week and seizure free was significant in LEV group than placebo group. There was no significance between LEV group and placebo group in the withdrawl rate (1000 mg/d: OR = 1.180, 95%CI: 0.690-2.010, P = 0.540; 2000 mg/d: OR = 1.530, 95%CI: 0.770-3.030, P = 0.230; 3000 mg/d: OR = 1.000, 95% CI: 0.620-1.600, P = 1.000. The following adverse events were associated with LEV: somnolence (OR = 1.720, 95%CI: 1.280-2.310, P = 0.000, dizziness (OR = 1.490, 95%CI: 1.000-2.220, P = 0.050, asthenia (OR = 1.670, 95%CI: 1.140-2.240, P = 0.008, nasopharyngitis (OR = 1.120, 95% CI: 0.710-1.760, P = 0.630, psychiatric and behavioral abnormalities (OR = 2.120, 95% CI: 1.370-3.280, P = 0.000. Conclusion LEV is effective and well tolerated when added to existing therapy in patients with refractory partial seizures compared with control drugs. Further studies are needed to identify the effects of monotherapy of LEV in partial seizures.

  16. Search for high entropy alloys in the X-NbTaTiZr systems (X = Al, Cr, V, Sn)

    Energy Technology Data Exchange (ETDEWEB)

    Poletti, Marco Gabriele, E-mail: marcogabriele.poletti@unito.it [Dipartimento di Chimica, Università di Torino, Via P. Giuria 7, 10125 Torino (Italy); Fiore, Gianluca [Dipartimento di Chimica, Università di Torino, Via P. Giuria 7, 10125 Torino (Italy); Szost, Blanka A. [Strategic and Emerging Technologies Team (TEC-TS), European Space Agency, ESTEC, 1 Keplerlaan, 2201 AZ Noordwijk (Netherlands); Battezzati, Livio [Dipartimento di Chimica, Università di Torino, Via P. Giuria 7, 10125 Torino (Italy)

    2015-01-25

    Highlights: • Composition of refractory high entropy alloys predicted. • Solid solutions found in VNbTaTiZr and AlNbTaTiZr. • Alloys containing Cr and Sn are multi-phased. - Abstract: High entropy alloys, i.e. solid solution phases, are sought in the X-NbTaTiZr equiatomic system where the X element was chosen as Al, Cr, V and Sn by applying recent criteria based on size and electronegativity mismatch of alloy components, number of itinerant and total valence electrons, and the temperature at which the free energy of mixing changes at the alloy composition. The alloys containing V and Al are mostly constituted by solid solutions in good agreement with prediction.

  17. Comprehensive Creep and Thermophysical Performance of Refractory Materials

    Energy Technology Data Exchange (ETDEWEB)

    Ferber, M.K.; Wereszczak, A.; Hemrick, J.A.

    2006-06-29

    Furnace designers and refractory engineers recognize that optimized furnace superstructure design and refractory selection are needed as glass production furnaces are continually striving toward greater output and efficiencies. Harsher operating conditions test refractories to the limit, while changing production technology (such as the conversion to oxy-fuel from traditional air-fuel firing) can alter the way the materials perform [1-3]. Refractories for both oxy- and air-fuel fired furnace superstructures (see Fig. 1) are subjected to high temperatures that may cause them to creep excessively or subside during service if the refractory material is not creep resistant, or if it is subjected to high stress, or both. Furnace designers can ensure that superstructure structural integrity is maintained if the creep behavior of the refractory material is well understood and well represented by appropriate engineering creep models. Several issues limit the abilities of furnace designers to (1) choose the optimum refractory for their applications, (2) optimize the engineering design, or (3) predict the service mechanical integrity of their furnace superstructures. Published engineering creep data are essentially nonexistent for almost all commercially available refractories used for glass furnace superstructures. The limited data that do exist are supplied by the various refractory suppliers. Unfortunately, the suppliers generally have different ways of conducting their mechanical testing, and they interpret and report their data differently. This inconsistency makes it hard for furnace designers to draw fair comparisons between competing grades of candidate refractories. Furthermore, the refractory suppliers' data are often not available in a form that can be readily used for furnace design or for the prediction and design of long-term structural integrity of furnace superstructures. As a consequence, the U.S. Department of Energy (DOE) Industrial Technology Program

  18. Export and Import Situation of Refractories and Refractory Raw Materials in China

    Institute of Scientific and Technical Information of China (English)

    PANShangxin; ZHANGZhongqi; 等

    2000-01-01

    The article states China is a great nation in producing and exporting refractories and refractory raw materials,which, has earned much foreign exchange for our country ,only a few advanced refactory material, zircon and chrome ore are needed to be imported.The ar-ticle points out the problems in the export and import,and raises suggestions on development.After the entry of WTO,China will expand its co-operations with other countries in science,technology,economy and trade to play a more important role in the world market.

  19. MAPPING FLOW LOCALIZATION PROCESSES IN DEFORMATION OF IRRADIATED REACTOR STRUCTURAL ALLOYS - FINAL REPORT. Nuclear Energy Research Initiative Program No. MSF99-0072. Period: August 1999 through September 2002. (ORNL/TM-2003/63)

    Energy Technology Data Exchange (ETDEWEB)

    Farrell, K.

    2003-09-26

    Metals that can sustain plastic deformation homogeneously throughout their bulk tend to be tough and malleable. Often, however, if a metal has been hardened it will no longer deform uniformly. Instead, the deformation occurs in narrow bands on a microscopic scale wherein stresses and strains become concentrated in localized zones. This strain localization degrades the mechanical properties of the metal by causing premature plastic instability failure or by inducing the formation of cracks. Irradiation with neutrons hardens a metal and makes it more prone to deformation by strain localization. Although this has been known since the earliest days of radiation damage studies, a full measure of the connection between neutron irradiation hardening and strain localization is wanting, particularly in commercial alloys used in the construction of nuclear reactors. Therefore, the goal of this project is to systematically map the extent of involvement of strain localization processes in plastic deformation of three reactor alloys that have been neutron irradiated. The deformation processes are to be identified and related to changes in the tensile properties of the alloys as functions of neutron fluence (dose) and degree of plastic strain. The intent is to define the role of strain localization in radiation embrittlement phenomena. The three test materials are a tempered bainitic A533B steel, representing reactor pressure vessel steel, an annealed 316 stainless steel and annealed Zircaloy-4 representing reactor internal components. These three alloys cover the range of crystal structures usually encountered in structural alloys, i.e. body-centered cubic (bcc), face-centered cubic (fcc), and close-packed hexagonal (cph), respectively. The experiments were conducted in three Phases, corresponding to the three years duration of the project. Phases 1 and 2 addressed irradiations and tensile tests made at near-ambient temperatures, and covered a wide range of neutron fluences

  20. Technology Progress of Refractories for Iron Making in China

    Institute of Scientific and Technical Information of China (English)

    CHAI Junlan; CHENG Qingxian; SHEN Keyin

    2005-01-01

    This paper reviews the present development situation of refractories for iron making system in China, which includes blast furnace, hot blast stove and coke dry quenching, etc. Varieties and performances of refractories used by the top steel and iron groups such as Baosteel, Wuhan I&S Group and Anshan I&S Group for iron making were exemplified and concerned problems were analyzed,together with solutions and suggestions for future refractories R&D work.

  1. TECHNOLOGICAL COMPLEX OF EQUIPMENT FOR REFINING AND CASTING OF STEEL AND ALLOYS IN THE FOUNDRY AND STEEL INDUSTRIES

    Directory of Open Access Journals (Sweden)

    V. I. Zolotukhin

    2013-01-01

    Full Text Available Vulcan TM is a small innovative company, specializing in the manufacture of steel and alloys casting systems and refractory accessories.Available for foundry and metallurgical industries, special technological equipment, designed and manufactured by LLC NPP “Vulkan-TM.”

  2. Preparation Methods and Properties of PdCu Alloy Membrane for Hydrogen Transition

    Institute of Scientific and Technical Information of China (English)

    SUN Xiaoliang; MA Guang; LI Jin; ZHANG Ke

    2012-01-01

    Pd and Pd alloy membranes are of increasing interest for hydrogen separation and purification due to their good thermal stability,high permeability and perfect selectivity.PdCu alloy (60wt% Pd) membranes have similar hydrogen permeability compared with PdAg alloy; meanwhile,it is cheaper than PdAg alloy.Furthermore,it has been reported that PdCu membrane has better resistance to poisoning and deactivation by H2S impurity.This paper reviews the properties and manufacturing methods of PdCu alloy membrane,finally,introduced some achievement made by us on PdCu alloy membrane.

  3. The manufacturing of lightweight refractories by direct freeze foaming technique; Die Herstellung von Feuerleichtsteinen ueber die Gefrier-Direktschaeumungsmethode

    Energy Technology Data Exchange (ETDEWEB)

    Ahlhelm, Matthias; Moritz, T.; Michaelis, A. [Fraunhofer-Institut fuer Keramische Technologien und Systeme IKTS, Dresden (Germany); Fruhstorfer, J. [IKGB Freiberg (Germany)

    2011-07-01

    Refractories are a key component for cost effective and energetic sustainable processes. Depending on the operation temperature of industrial furnace thermal characteristics of porous refractory linings have to be adjusted. There are a lot of possible porosity adjusting methods, e.g. placeholder, replica and gas injection/development approaches. Now, the freeze-foaming as direct foaming technique shall be introduced as an environmentally friendly way to refractories. In this presented work an aqueous ceramic mullite suspension is foamed within minutes just by the reduction of the ambient pressure in a freeze drying device. The foam structure suddenly freezes when the suspension temperature, related to the vacuum pressure, reaches the liquid-solid equilibrium line (p, T-diagram of water). The porous structure is then dried by sublimating the frozen water. The resulting bricklike lightweight refractories exhibit a high amount of open porosity and dense struts. Just 5-10 mass.% organic additives, required for a stable foaming, minimize the effect of crack formation during the sintering step and provide an environmentally friendly processing route to the final product. The pore morphology is being determined by X-ray computed tomographic images and mercury porosimetry. Measurements of the thermal conductivity, compressive strength and creep have been carried out to evaluate the freeze-foaming process as a promising approach for manufacturing refractories. (orig.)

  4. Properties of Refractory Concrete in Tension and Compression

    Science.gov (United States)

    Sampson, Jeffrey

    2009-01-01

    Refractory concrete on the LC-39A Flame Deflector has been damaged during multiple Space Shuttle launches (e.g. STS-124, STS-126, STS-119, and STS-125, STS-127). These events have prompted a better understanding of the system via an analytical model of the Flame Deflector assembly to include the Fondu Fyre refractory concrete. This model requires test data inputs of the refractory concrete's mechanical properties, which include stress versus strain curves in tension and compression, modulus of elasticity, and Poisson's ratio. Sections of Fondu Fyre refractory concrete removed from the LC-39A Flame Deflector were provided for this testing.

  5. Bendamustine Plus Alemtuzumab for Refractory Chronic Lymphocytic Leukemia (CLL)

    Science.gov (United States)

    2013-08-20

    Recurrent Small Lymphocytic Lymphoma; Refractory Chronic Lymphocytic Leukemia; Stage III Chronic Lymphocytic Leukemia; Stage III Small Lymphocytic Lymphoma; Stage IV Chronic Lymphocytic Leukemia; Stage IV Small Lymphocytic Lymphoma

  6. Ketogenic diet therapy is effective in encephalitis with refractory seizures.

    Science.gov (United States)

    Matsuzono, Kosuke; Kurata, Tomoko; Deguchi, Shoko; Yamashita, Toru; Deguchi, Kentaro; Abe, Koji

    2014-10-01

    Although ketogenic diet therapy is effective in refractory seizures in childhood, its effect on adult encephalitis with similar refractory seizures and prolonged encephalopathy has not been well reported. We report here a case of a 22-year-old man with acute encephalitis with refractory repetitive partial seizures (AERRPS). Partial seizures of the face developed to repeated generalized convulsions, which were refractory against anti-epileptic drugs and a high dose of propofol. After struggling for 9 months, he dramatically recovered after ketogenic diet therapy. Ketogenic diet therapy may be an important tool to help cure AERRPS.

  7. Refractory Coated/Lined Low Density Structures Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This project addresses the development of refractory coated or lined low density structures applicable for advanced future propulsion system technologies. The...

  8. Handbook of industrial refractories technology principles, types, properties and applications

    CERN Document Server

    Caniglia, Stephen

    1989-01-01

    Encompasses the entire range of industrial refractory materials and forms: properties and their measurement, applications, manufacturing, installation and maintenance techniques, quality assurance, and statistical process control.

  9. Alloy Design Challenge: Development of Low Density Superalloys for Turbine Blade Applications

    Science.gov (United States)

    MacKay, Rebecca A.; Gabb, Timothy P.; Smialek, James L.; Nathal, Michael V.

    2009-01-01

    New low density single crystal (LDS) alloys have been developed for turbine blade applications, which have the potential for significant improvements in the thrust to weight ratio over current production alloys. An innovative alloying strategy was identified to achieve high temperature creep resistance, alloy density reductions, microstructural stability, and cyclic oxidation resistance. The approach relies on the use of molybdenum (Mo) as a potent solid solution strengthener for the nickel (Ni)-base superalloy; Mo has a density much closer to Ni than other refractory elements, such as rhenium (Re) or tungsten (W). A host of testing and microstructural examinations was conducted on the superalloy single crystals, including creep rupture testing, microstructural stability, cyclic oxidation, and hot corrosion. The paper will provide an overview of the single crystal properties that were generated in this new superalloy design space. The paper will also demonstrate the feasibility of this innovative approach of low density single crystal superalloy design. It will be shown that the best LDS alloy possesses the best attributes of three generations of single crystal alloys: the low density of first-generation single crystal alloys, the excellent oxidation resistance of second-generation single crystal alloys, and a creep strength which exceeds that of second and third generation alloys.

  10. Launch Pad Flame Trench Refractory Materials

    Science.gov (United States)

    Calle, Luz M.; Hintze, Paul E.; Parlier, Christopher R.; Bucherl, Cori; Sampson, Jeffrey W.; Curran, Jerome P.; Kolody, Mark; Perusich, Steve; Whitten, Mary

    2010-01-01

    The launch complexes at NASA's John F. Kennedy Space Center (KSC) are critical support facilities for the successful launch of space-based vehicles. These facilities include a flame trench that bisects the pad at ground level. This trench includes a flame deflector system that consists of an inverted, V-shaped steel structure covered with a high temperature concrete material five inches thick that extends across the center of the flame trench. One side of the "V11 receives and deflects the flames from the orbiter main engines; the opposite side deflects the flames from the solid rocket boosters. There are also two movable deflectors at the top of the trench to provide additional protection to shuttle hardware from the solid rocket booster flames. These facilities are over 40 years old and are experiencing constant deterioration from launch heat/blast effects and environmental exposure. The refractory material currently used in launch pad flame deflectors has become susceptible to failure, resulting in large sections of the material breaking away from the steel base structure and creating high-speed projectiles during launch. These projectiles jeopardize the safety of the launch complex, crew, and vehicle. Post launch inspections have revealed that the number and frequency of repairs, as well as the area and size of the damage, is increasing with the number of launches. The Space Shuttle Program has accepted the extensive ground processing costs for post launch repair of damaged areas and investigations of future launch related failures for the remainder of the program. There currently are no long term solutions available for Constellation Program ground operations to address the poor performance and subsequent failures of the refractory materials. Over the last three years, significant liberation of refractory material in the flame trench and fire bricks along the adjacent trench walls following Space Shuttle launches have resulted in extensive investigations of

  11. Bulk Vitrification Castable Refractory Block Protection Study

    Energy Technology Data Exchange (ETDEWEB)

    Hrma, Pavel R.; Bagaasen, Larry M.; Beck, Andrew E.; Brouns, Thomas M.; Caldwell, Dustin D.; Elliott, Michael L.; Matyas, Josef; Minister, Kevin BC; Schweiger, Michael J.; Strachan, Denis M.; Tinsley, Bronnie P.; Hollenberg, Glenn W.

    2005-05-01

    Bulk vitrification (BV) was selected for a pilot-scale test and demonstration facility for supplemental treatment to accelerate the cleanup of low-activity waste (LAW) at the Hanford U.S. DOE Site. During engineering-scale (ES) tests, a small fraction of radioactive Tc (and Re, its nonradioactive surrogate) were transferred out of the LAW glass feed and molten LAW glass, and deposited on the surface and within the pores of the castable refractory block (CRB). Laboratory experiments were undertaken to understand the mechanisms of the transport Tc/Re into the CRB during vitrification and to evaluate various means of CRB protection against the deposition of leachable Tc/Re. The tests used Re as a chemical surrogate for Tc. The tests with the baseline CRB showed that the molten LAW penetrates into CRB pores before it converts to glass, leaving deposits of sulfates and chlorides when the nitrate components decompose. Na2O from the LAW reacts with the CRB to create a durable glass phase that may contain Tc/Re. Limited data from a single CRB sample taken from an ES experiment indicate that, while a fraction of Tc/Re is present in the CRB in a readily leachable form, most of the Tc/Re deposited in the refractory is retained in the form of a durable glass phase. In addition, the molten salts from the LAW, mainly sulfates, chlorides, and nitrates, begin to evaporate from BV feeds at temperatures below 800 C and condense on solid surfaces at temperatures below 530 C. Three approaches aimed at reducing or preventing the deposition of soluble Tc/Re within the CRB were proposed: metal lining, sealing the CRB surface with a glaze, and lining the CRB with ceramic tiles. Metal liners were deemed unsuitable because evaluations showed that they can cause unacceptable distortions of the electric field in the BV system. Sodium silicate and a low-alkali borosilicate glaze were selected for testing. The glazes slowed down molten salt condensate penetration, but did little to reduce the

  12. Translating VDM to Alloy

    DEFF Research Database (Denmark)

    Lausdahl, Kenneth

    2013-01-01

    . Traditionally, theorem provers are used to prove that specifications are correct but this process is highly dependent on expert users. Alternatively, model finding has proved to be useful for validation of specifications. The Alloy Analyzer is an automated model finder for checking and visualising Alloy...... specifications. However, to take advantage of the automated analysis of Alloy, the model-oriented VDM specifications must be translated into a constraint-based Alloy specifications. We describe how a sub- set of VDM can be translated into Alloy and how assertions can be expressed in VDM and checked by the Alloy...

  13. Room temperature creep in metals and alloys

    Energy Technology Data Exchange (ETDEWEB)

    Deibler, Lisa Anne [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Materials Characterization and Performance

    2014-09-01

    Time dependent deformation in the form of creep and stress relaxation is not often considered a factor when designing structural alloy parts for use at room temperature. However, creep and stress relaxation do occur at room temperature (0.09-0.21 Tm for alloys in this report) in structural alloys. This report will summarize the available literature on room temperature creep, present creep data collected on various structural alloys, and finally compare the acquired data to equations used in the literature to model creep behavior. Based on evidence from the literature and fitting of various equations, the mechanism which causes room temperature creep is found to include dislocation generation as well as exhaustion.

  14. Arthroscopic capsular release for refractory shoulder stiffness.

    Science.gov (United States)

    Fernandes, Marcos Rassi

    2013-01-01

    To evaluate the results of the arthroscopic treatment of refractory adhesive capsulitis of the shoulder with two to nine years of follow-up, comparing the pre- and postoperative range of motion. This was an observational study (case series) of 18 patients who underwent arthroscopic capsular release for refractory shoulder stiffness. The mean age was of 53.6 years (range: 39 to 68), with female predominance (77.77%) and nine cases left shoulders. There were 6 primary (33.33%) and 12 secondary cases (66.67%). Arthroscopic capsular release was performed in all patients after a mean of 9.33 months of physical therapy (range: 6 to 20 months) with a minimum follow-up of two years (range: 26 to 110 months). The mean active and passive forward flexion, external rotation and internal rotation increased from 94.4°/103.3°, 11.9°/21.9°, and S1/L5 vertebral level, respectively, to 151.1°/153.8°, 57.2°/64.4°, and T12/T10 vertebral level, respectively. There was a significant difference between the pre- and postoperative range of motion (p < 0.001). According to the Constant-Murley functional score (ROM), the value increased from 14 (preoperative mean) to 30 points (postoperative mean). Postoperatively, all patients showed diminished shoulder pain (none or mild/15 or 10 points in the Constant-Murley score). Arthroscopic treatment is an effective treatment for refractory shoulder stiffness. Copyright © 2013 Elsevier Editora Ltda. All rights reserved.

  15. Gastroesophageal Reflux in Children with Refractory Asthma

    Directory of Open Access Journals (Sweden)

    Alaa S. Deeb

    2010-07-01

    Full Text Available Objectives: To investigate the association between clinical and macroscopic findings of GER and severity of refractory asthma (statistical study.Methods: A prospective study in a university-based practice of 75 children who were diagnosed with refractory asthma because they exhibited no satisfactory response for at least three months of treatment. Medical history, physical examination, spirometrical measurements and prick skin test were conducted on all patients. Endoscopic and macroscopic evaluations for esophagitis were performed on all patients regardless of the presence of GER symptoms.Results: Endoscopy was done for 75 children with refractory asthma. GER was symptomatic in 65% of all patients with no statistical significance (p>0.05 and the most frequent symptom was abdominal pain (67%. The frequency of these symptoms was 50% in mild asthma, 58% in moderate asthma and 72% in severe asthma with no statistical significance (p>0.05. The frequency of macroscopic esophagitis was 71%, distributed in three asthmatic groups as in order of 75% in mild asthma, 58.3% in moderate asthma and 76.6% in severe asthma (p>0.05. Regarding the relationship between GER and nocturnal attacks or spasmodic cough, the frequency of the latest was 66.7%. The differences have no statistical significance regarding GER symptoms (p>0.05, but they are statistically significant regarding the reflux esophagitis (p<0.05. Also endoscopic reflux was as frequent as76.3% in non allergic patients, and this result is statistically significant (p<0.05.Conclusion: In spite of the fact that there was no relationship between the severity of asthma and the symptoms of GER, or its endoscopic findings, the frequency of GER in asthmatic children was higher than its frequency in other children.

  16. Refractory thrombotic thrombocytopenic purpura following acute pancreatitis

    Institute of Scientific and Technical Information of China (English)

    Ebisa Bekele; Bethel Shiferaw; Alexandra Sokolova; Arpan Shah; Phillip Saunders; Alida Podrumar; Javed Iqbal

    2016-01-01

    Thrombotic thrombocytopenic purpura (TTP) is a rare blood disorder with an estimated incidence of 4–5 cases per million people per year. It is characterized by small-vessel platelet-rich thrombi that cause thrombocytopenia, microangiopathic hemolytic anemia and organ damage. There are reports in literature that TTP and acute pancreatitis are associated, indicating each can be the cause of the other. However, acute pancreatitis triggering TTP is very rare. A 71 years old female presented with abdominal pain of 3 days, followed by dark urine. She had icteric sclera, petechial rash and mild epigastric tenderness. Lab findings were significant for hemolytic anemia, thrombocytopenia and elevated lipase. CT of abdomen showed evidence of pancreatitis and cholelithiasis. After admission, patient developed symptoms of stroke. Further investigation showed elevated lactate dehydrogenase and normal coagulation studied with peripheral blood smear showed 5–6 schistocytes/high power field. Disintegrin and metalloproteinase with thrombospondin motifs-13 (ADAMTS13) activity showed less than 3% with high ADAMTS13 inhibitor 2.2. Patient required 6–7 weeks of daily plasmapheresis until she showed complete response. Our patient presented with clinical features of pancreatitis prior to having dark urine and petechial rash. Therefore, we strongly believe that our patient had pancreatitis which was followed by TTP. Patient's ADMTS13 activity was 6%after 10 plasma exchanges, signifying refractory TTP and higher risk for morbidity and mortality. There are limited data and consensus on the management of refractory TTP. TTP and acute pancreatitis are associated. However, refractory TTP following acute pancreatitis is rarely mentioned in the literature. We would like to emphasize the importance of having higher clinical suspicion of the association of both disease entities.

  17. Refractory leg ulcers associated with Klinefelter syndrome.

    Science.gov (United States)

    Yabuno, Yuto; Tosa, Mamiko; Iwakiri, Itaru; Nomoto, Shunichi; Kaneko, Mayuko; Kuwahara, Kousuke; Hyakusoku, Hiko; Murakami, Masahiro

    2015-01-01

    We present a man with refractory leg ulcers, bilateral varicosis of the lower extremities, and Buerger disease. Autoimmune work-up was negative. However, chromosome analysis showed Klinefelter syndrome (48 XXY). Ulcerative lesions of the lower extremities are a complication of Klinefelter syndrome. To date, the pathogenesis of ulcers in Klinefelter syndrome has not been clarified, but several factors, such as abnormalities of fibrinolysis and prothrombotic states, might be involved. Our present case emphasizes the importance of considering Klinefelter syndrome in the differential diagnosis of a male patient with nonhealing ulcers of the lower extremities.

  18. Refractory overactive bladder: Beyond oral anticholinergic therapy

    Directory of Open Access Journals (Sweden)

    Ronald W Glinski

    2007-01-01

    Full Text Available Objectives: In this review, we discuss the treatment of refractory overactive bladder (OAB that has not adequately responded to medication therapy and we propose an appropriate care pathway to the treatment of OAB. We also attempt to address the cost of OAB treatments. Materials and Methods: A selective expert review of the current literature on the subject of refractory OAB using MEDLINE was performed and the data is summarized. We also review our experience in treating refractory OAB. The role and outcomes of various treatment options for refractory OAB are discussed and combined therapy with oral anticholinergics is explored. Emerging remedies including intravesical botulinum toxin injection and pudendal neuromodulation are also reviewed, along with conventional surgical options. Results: In general behavioral therapy, pelvic floor electrical stimulation, magnetic therapy and posterior tibial nerve stimulation (PTNS, have shown symptom decreases in 50-80% of patients with OAB. Depending on the study, combination therapy with oral anticholinergics seems to improve efficacy of behavioral therapy and PTNS in approximately 10-30%. In multicenter, long-term randomized controlled trials, sacral neuromodulation has been shown to improve symptoms of OAB and OAB incontinence in up to 80% of the patients treated. Studies involving emerging therapies such as pudendal serve stimulation suggest that there may be a 15-20% increase in efficacy over sacral neuromodulation, but long-term studies are not yet available. Another emerging therapy, botulinum toxin, is also showing similar success in reducing OAB symptoms in 80-90% of patients. Surgical approaches, such as bladder augmentation, are a last resort in the treatment of OAB and are rarely used at this point unless upper tract damage is a concern and all other treatment options have been exhausted. Conclusion: The vast majority of OAB patients can be managed successfully by behavioral options with or

  19. Management in refractory epilepsy: Beyond epilepsy surgery...

    Directory of Open Access Journals (Sweden)

    Roop Gursahani

    2008-01-01

    Full Text Available Although definititions of refractory epilepsy vary, about 40% of prevalent cases of epilepsy are not controlled by anti-epileptic drugs. A substantial proportion of this population requires palliative therapy since only a minority are candidates for epilepsy surgery. Drug therapy can be optimised after accurate classification of the epilepsy. Monotherapy is often as effective as polytherapy with fewer adverse effects. Depression and CNS adverse effects significantly impact quality of life and must be systematically screened for and treated. The ketogenic diet and vagal nerve stimulation provide substantial seizure control in a significant number of cases and may be used synergistically. Deep brain stimulation is another promising modality.

  20. Deoxyspergualin in relapsing and refractory Wegener's granulomatosis

    DEFF Research Database (Denmark)

    Flossmann, O; Baslund, B; Bruchfeld, A

    2008-01-01

    at entry and prednisolone doses adjusted according to clinical status. Deoxyspergualin, 0.5 mg/kg per day, was self-administered by subcutaneous injection in six cycles of 21 days with a 7-day washout between cycles. Cycles were stopped early for white blood count less than 4000 cells/mm(3). The primary......-threatening (> or = grade 3) treatment-related adverse events occurred in 24 (53%) patients mostly due to leucopaenias. CONCLUSIONS: Deoxyspergualin achieved a high rate of disease remission and permitted prednisolone reduction in refractory or relapsing Wegener's granulomatosis. Adverse events were common but rarely led...

  1. Flow and Flow Decay of Refractory Castables

    Institute of Scientific and Technical Information of China (English)

    CHEN Zhiqiang; Bjom Myhre; Bjorn Sandberg

    2003-01-01

    Installation of refractoty castables depend not only on flow, but also on how soon the flow is lost because of setting. The loss of flow (flow decay) has always been one of the main problems of refractory castable manufacturers,a problem that has not been too well described in literature. The flow decay has been studied for a castable system based on alumina, pointing out some general trends. The flow decay was found very temperature sensitive, being strongly accelerated by termperature increases. To compensate for excessive flow loss, a retarder like citric acid may be used. Thus flow decay was measured as a function of citric acid (retarder) addition at 35 ℃ .

  2. Obtaining Multiple Metals Through Electron Beam Melting of Refractory Metal Wastes

    Science.gov (United States)

    Vutova, Katia; Vassileva, Vania

    Investigations and results on the refining of tungsten scrap applying electron beam melting (EBM) in vacuum are presented and discussed. In this work EB melting experiments were performed in single or double-melt operations with different power inputs and refining times for tungsten purification and recovery of multiple metals (including refractory and other metals such as Mo, Nb, Cu, Zn, etc.), which are alloyed elements or impurities with high concentrations in the initial materials. Evaluations for extraction of some valuable metals, generated in the condensate at their removal from the liquid metal during the refining process are provided. Efficient technological regimes for e-beam melting and refining that enable the simultaneous production of pure metal ingots and condensates that can be used directly or can be used for subsequent extraction of expensive and valuable metals are presented.

  3. Project on New Domestic Zirconium Alloy Fuel Assembly Irradiation

    Institute of Scientific and Technical Information of China (English)

    ZHANG; Pei-sheng; ZHANG; Ai-min

    2012-01-01

    <正>The objectives of the project is to conduct irradiation at research reactor for small fuel assembly with domestic new zirconium alloy, and then to carry out post irradiation examination, and finally to acquire

  4. Electroplated solder alloys for flip chip interconnections

    Science.gov (United States)

    Annala, P.; Kaitila, J.; Salonen, J.

    1997-01-01

    Flip chip mounting of bare dice is gaining widespread use in microelectronics packaging. The main drivers for this technology are high packaging density, improved performance at high frequency, low parasitic effects and potentially high reliability and low cost. Many companies have made significant efforts to develop a technology for bump processing, bare die testing and underfill encapsulation to gain the benefit of all potential advantages. We have focussed on low cost bumping of fully processed silicon wafers to develop a flexible scheme for various reflow requirements. The bumping process is based on galvanic plating from an alloy solution or, alternatively, from several elemental plating baths. Sputtered Mo/Cu or Cr/Cu is used as a wettable base for electroplating. Excess base metal is removed by using the bumps as an etching mask. Variation of the alloy composition or the layer structure, allows the adjustment of the bump reflow temperature for the specific requirements of the assembly. Using binary tin-lead and ternary tin-lead-bismuth alloys, reflow temperatures from 100 °C (bismuth rich alloys) to above 300 °C (lead rich alloys) can be covered. The influence of the plating current density on the final alloy composition has been established by ion beam analysis of the plated layers and a series of reflow experiments. To control the plating uniformity and the alloy composition, a new cup plating system has been built with a random flow pattern and continuous adjustment of the current density. A well-controlled reflow of the bumps has been achieved in hot glycerol up to the eutectic point of tin-lead alloys. For high temperature alloys, high molecular weight organic liquids have been used. A tensile pull strength of 20 g per bump and resistance of 5 mΩ per bump have been measured for typical eutectic tin-lead bumps of 100 μm in diameter.

  5. Comparative studies on ultrasonic, friction, laser and resistance pressure welding of NiTi shape memory alloys with high-alloy steels. Final report; Vergleichende Untersuchungen zum Ultraschall-, Reib-, Laserstrahl- und Widerstandspressschweissen von NiTi-Shape-Memory-Metall mit hochlegierten Staehlen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Zuckschwerdt, K.

    2000-04-01

    The suitability of different welding techniques for welding of NiTi shape memory alloys with high-alloy steel (C12CrNi17-7, X5CrNiNb19-9, X20Cr13) was investigated. The quality of the welds was analyzed using mechanical-technological, fractographic, metallographic and electron microscopy analysis. [German] Ziel dieses Forschungsvorhabens ist es, die Eignung der einzelnen Schweissverfahren fuer das Fuegen von NiTi-Formgedaechtnislegierungen mit hochlegiertem Stahl (X12CrNi17-7, X5CrNiNb19-9, X20Cr13) darzustellen und zu beurteilen. Die Qualitaet der Fuegeverbindungen wird mit Hilfe mechanisch-technologischer, fraktographischer, metallographischer und elektronenmikroskopischer Untersuchungen bewertet.

  6. Alloy Fabrication Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — At NETL’s Alloy Fabrication Facility in Albany, OR, researchers conduct DOE research projects to produce new alloys suited to a variety of applications, from gas...

  7. Turbine Blade Alloy

    Science.gov (United States)

    MacKay, Rebecca

    2001-01-01

    The High Speed Research Airfoil Alloy Program developed a fourth-generation alloy with up to an +85 F increase in creep rupture capability over current production airfoil alloys. Since improved strength is typically obtained when the limits of microstructural stability are exceeded slightly, it is not surprising that this alloy has a tendency to exhibit microstructural instabilities after high temperature exposures. This presentation will discuss recent results obtained on coated fourth-generation alloys for subsonic turbine blade applications under the NASA Ultra-Efficient Engine Technology (UEET) Program. Progress made in reducing microstructural instabilities in these alloys will be presented. In addition, plans will be presented for advanced alloy development and for computational modeling, which will aid future alloy development efforts.

  8. Separating refractory and non-refractory particulate chloride and estimating chloride depletion by aerosol mass spectrometry in a marine environment

    Directory of Open Access Journals (Sweden)

    I. Nuaaman

    2015-01-01

    Full Text Available Aerosol composition and concentration measurements along the coast of California were obtained using an Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-AMS onboard the research vessel Atlantis during the CalNex study in 2010. This paper focuses on the measurement of aerosol chloride using the HR-AMS that can be ambiguous in regions with significant quantities of sea salt aerosols. This ambiguity arises due to large differences in the sensitivity of the HR-AMS to refractory chloride species (i.e., NaCl and non refractory chloride species (i.e., NH4Cl, HCl, etc.. Using the HR-AMS, the aerosol chloride signal is typically quantified using ion signals for 35Cl+, H35Cl+, 37Cl+ and H37Cl+ (HxCl+. During this study, the highest aerosol chloride signal was observed during sea sweep experiments when the source of the aerosol chloride was NaCl present in artificially generated sea salt aerosols even though the HR-AMS has significantly lower sensitivity to such refractory species. Other prominent ion signals that arise from NaCl salt were also observed at m/z 22.99 for Na+ and m/z 57.96 for Na35Cl+ during both sea sweep experiments and during periods of ambient measurements. Thus, refractory NaCl contributes significantly to the HxCl+ signal, interfering with attempts to quantify non sea salt chloride (nssCl. It was found that during ambient aerosol measurements, the interference in the HxCl+ signal from sea salt chloride (ssCl was as high as 89%, but with a study wide average of 10%. The Na35Cl+ ion signal was found to be a good tracer for NaCl. We outline a method to establish nssCl in the ambient aerosols by subtracting the sea salt chloride (ssCl signal from the HxCl+ signal. The ssCl signal is derived from the Na35Cl+ ion tracer signal and the HxCl+ to Na35Cl+ ratio established from the sea sweep experiments. Ambient submicron concentrations of ssCl were also established using the

  9. Predictions of titanium alloy properties using thermodynamic modeling tools

    Science.gov (United States)

    Zhang, F.; Xie, F.-Y.; Chen, S.-L.; Chang, Y. A.; Furrer, D.; Venkatesh, V.

    2005-12-01

    Thermodynamic modeling tools have become essential in understanding the effect of alloy chemistry on the final microstructure of a material. Implementation of such tools to improve titanium processing via parameter optimization has resulted in significant cost savings through the elimination of shop/laboratory trials and tests. In this study, a thermodynamic modeling tool developed at CompuTherm, LLC, is being used to predict β transus, phase proportions, phase chemistries, partitioning coefficients, and phase boundaries of multicomponent titanium alloys. This modeling tool includes Pandat, software for multicomponent phase equilibrium calculations, and PanTitanium, a thermodynamic database for titanium alloys. Model predictions are compared with experimental results for one α-β alloy (Ti-64) and two near-β alloys (Ti-17 and Ti-10-2-3). The alloying elements, especially the interstitial elements O, N, H, and C, have been shown to have a significant effect on the β transus temperature, and are discussed in more detail herein.

  10. Cast iron-base alloy for cylinder/regenerator housing

    Science.gov (United States)

    Witter, Stewart L.; Simmons, Harold E.; Woulds, Michael J.

    1985-01-01

    NASACC-1 is a castable iron-base alloy designed to replace the costly and strategic cobalt-base X-40 alloy used in the automotive Stirling engine cylinder/generator housing. Over 40 alloy compositions were evaluated using investment cast test bars for stress-rupture testing. Also, hydrogen compatibility and oxygen corrosion resistance tests were used to determine the optimal alloy. NASACC-1 alloy was characterized using elevated and room temperature tensile, creep-rupture, low cycle fatigue, heat capacity, specific heat, and thermal expansion testing. Furthermore, phase analysis was performed on samples with several heat treated conditions. The properties are very encouraging. NASACC-1 alloy shows stress-rupture and low cycle fatigue properties equivalent to X-40. The oxidation resistance surpassed the program goal while maintaining acceptable resistance to hydrogen exposure. The welding, brazing, and casting characteristics are excellent. Finally, the cost of NASACC-1 is significantly lower than that of X-40.

  11. Status epilepticus: Analysis of refractory cases

    Directory of Open Access Journals (Sweden)

    B. P. Gladov

    2016-01-01

    Full Text Available Objective: to analyze refractory status epilepticus (SE cases.Patients and methods. Fifteen female patients aged 21 to 62 years with refractory SE were comprehensively examined using long-term electroencephalography monitoring. The investigators evaluated the efficiency of treatment regimens with intravenous antiepileptic drugs (AEDs, such as diazepam (DZP; valproic acid (VPA; levetiracetam; and lacosamide and their combinations, at the prehospital and hospital stages, as well as SE therapy complications noted only in the intravenous administration of narcotics (propofol, sodium thiopental.Results and discussion. A fetal outcome due to multiple organ dysfunction indirectly related to SE was recorded in 2 (13.3% patients with acute symptomatic status. SE was abolished in the other 13 cases. The preliminary findings may suggest that it is appropriate to prescribe VPA just at the prehospital stage. The co-administration of VPA and DZP substantially enhances the efficiency of SE therapy. The maximum acceptable doses of AEDs using the whole available therapeutic arsenal should be administered within the first hours of acute symptomatic SE.

  12. Liposteroid therapy for refractory seizures in children.

    Science.gov (United States)

    Yoshikawa, H; Yamazaki, S; Abe, T; Oda, Y

    2000-10-01

    Liposteroid is dexamethasone palmitate incorporated into liposomes and was developed as an anti-inflammatory drug for targeting therapy mainly for rheumatoid arthritis. Recently, it was reported that liposteroid might be effective for the treatment of West syndrome, with fewer side effects than those of corticotropin therapy. We describe three patients, a 2-month-old boy with early infantile epileptic encephalopathy, a 4-month-old girl with symptomatic West syndrome, and a 2-year-old girl with symptomatic localization-related epilepsy, whose refractory seizures were treated with liposteroid according to the original method reported by Yamamoto and colleagues in 1998. Uncontrollable seizures ceased completely in two patients and the seizure frequency decreased markedly in the other patient. Electroencephalograms revealed marked improvement in all patients. They showed no relapse of the seizures, and all showed no adverse effects except for mild brain shrinkage in one patient. Our experience with these three patients suggests that liposteroid therapy might be a new option for the treatment of refractory seizures in children, as well as for West syndrome.

  13. [Iron-refractory iron deficiency anemia].

    Science.gov (United States)

    Kawabata, Hiroshi

    2016-02-01

    The major causes of iron deficiency anemia (IDA) include iron loss due to bleeding, increased iron requirements, and decreased iron absorption by the intestine. The most common cause of IDA in Japanese women is iron loss during menstruation. Autoimmune atrophic gastritis and Helicobacter pylori infection can also cause IDA by reducing intestinal iron absorption. In addition to these common etiologies, germline mutations of TMPRSS6 can cause iron-refractory IDA (IRIDA). TMPRSS6 encodes matriptase-2, a membrane-bound serine protease primarily expressed in the liver. Functional loss of matriptase-2 due to homozygous mutations results in an increase in the expression of hepcidin, which is the key regulator of systemic iron homeostasis. The serum hepcidin increase in turn leads to a decrease in iron supply from the intestine and macrophages to erythropoietic cells. IRIDA is microcytic and hypochromic, but decreased serum ferritin is not observed as in IDA. IRIDA is refractory to oral iron supplementation, but does respond to intravenous iron supplementation to some extent. Because genetic testing is required for the diagnoses of IRIDA, a considerable number of cases may go undiagnosed and may thus be overlooked.

  14. Characterization of novel W alloys produced by HIP

    Energy Technology Data Exchange (ETDEWEB)

    Monge, M.A.; Auger, M.A.; Leguey, T.; Pareja, R. [Universidad Carlos 3, Dept. de Fisica, Madrid (Spain); Bolzoni, L.; Gordo, E. [Universidad Carlos 3, Dept. de Ciencias de Materiales, Madrid (Spain)

    2007-07-01

    Full text of publication follows: Tungsten is considered as a candidate material for plasma-facing components (PFCs) in a future fusion power reactor because of its refractory characteristics, low tritium retention and low sputtering yielding. However, its use in PFCs requires the development of a tungsten material that, in addition to these properties, maintains good mechanical properties after a prolonged exposure at high temperatures. Sintering would be the most suitable method to produce tungsten materials for these applications if their recrystallization temperature is high enough and the grain growth is restrained. Usual sintering conditions for tungsten requires very high temperatures that induces a coarse grained structure in the sintered material, and a low recrystallization temperature in the hot worked material. This causes the failure of its mechanical properties. The combined addition of a sintering activator, which lowers the sintering temperature and favors the densification, and an insoluble oxide that produces a dispersion strengthening and grain growth inhibition, may result in a tungsten material with improved mechanical characteristics. Cu, Ni and Fe are the most used activators to produce tungsten heavy alloys but they may be no recommendable for PFCs. The present work assesses the possibility of using jointly Ti as sintering activator and Y{sub 2}O{sub 3} particles as strengthening dispersoids in tungsten. Pure tungsten and tungsten alloys having 0.5 wt % Y{sub 2}O{sub 3}, x wt % Ti and 0.5 wt % Y{sub 2}O{sub 3}+ x wt % Ti have been prepared by powder metallurgy; 0{<=}x{<=}4%. Elemental powders were blended or ball milled, canned, out-gassed and finally consolidated by a two-stage HIP process under a pressure of 200 MPa. The first stage was performed at 1523 K for 2 h, and after un-canning, the second HIP at 1973 K for 30 min. It is found that Ti addition favors the densification attaining a fully dense material, while pure W and W-0.5Y{sub 2

  15. New Developments of Ti-Based Alloys for Biomedical Applications

    Directory of Open Access Journals (Sweden)

    Yuhua Li

    2014-03-01

    Full Text Available Ti-based alloys are finding ever-increasing applications in biomaterials due to their excellent mechanical, physical and biological performance. Nowdays, low modulus β-type Ti-based alloys are still being developed. Meanwhile, porous Ti-based alloys are being developed as an alternative orthopedic implant material, as they can provide good biological fixation through bone tissue ingrowth into the porous network. This paper focuses on recent developments of biomedical Ti-based alloys. It can be divided into four main sections. The first section focuses on the fundamental requirements titanium biomaterial should fulfill and its market and application prospects. This section is followed by discussing basic phases, alloying elements and mechanical properties of low modulus β-type Ti-based alloys. Thermal treatment, grain size, texture and properties in Ti-based alloys and their limitations are dicussed in the third section. Finally, the fourth section reviews the influence of microstructural configurations on mechanical properties of porous Ti-based alloys and all known methods for fabricating porous Ti-based alloys. This section also reviews prospects and challenges of porous Ti-based alloys, emphasizing their current status, future opportunities and obstacles for expanded applications. Overall, efforts have been made to reveal the latest scenario of bulk and porous Ti-based materials for biomedical applications.

  16. New Developments of Ti-Based Alloys for Biomedical Applications

    Science.gov (United States)

    Li, Yuhua; Yang, Chao; Zhao, Haidong; Qu, Shengguan; Li, Xiaoqiang; Li, Yuanyuan

    2014-01-01

    Ti-based alloys are finding ever-increasing applications in biomaterials due to their excellent mechanical, physical and biological performance. Nowdays, low modulus β-type Ti-based alloys are still being developed. Meanwhile, porous Ti-based alloys are being developed as an alternative orthopedic implant material, as they can provide good biological fixation through bone tissue ingrowth into the porous network. This paper focuses on recent developments of biomedical Ti-based alloys. It can be divided into four main sections. The first section focuses on the fundamental requirements titanium biomaterial should fulfill and its market and application prospects. This section is followed by discussing basic phases, alloying elements and mechanical properties of low modulus β-type Ti-based alloys. Thermal treatment, grain size, texture and properties in Ti-based alloys and their limitations are dicussed in the third section. Finally, the fourth section reviews the influence of microstructural configurations on mechanical properties of porous Ti-based alloys and all known methods for fabricating porous Ti-based alloys. This section also reviews prospects and challenges of porous Ti-based alloys, emphasizing their current status, future opportunities and obstacles for expanded applications. Overall, efforts have been made to reveal the latest scenario of bulk and porous Ti-based materials for biomedical applications. PMID:28788539

  17. Refractory Degradation by Slag Attack in Coal Gasification

    Science.gov (United States)

    2009-02-01

    REFRACTORY DEGRADATION BY SLAG ATTACK IN COAL GASIFICATION Jinichiro Nakano 1,2 , Sridhar Seetharaman 1,2 , James Bennett 3 , Kyei-Sing...00-2009 4. TITLE AND SUBTITLE Refractory Degradation by Slag Attack in Coal Gasification 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM

  18. ZrO2-Containing Refractories for Cement Rotary Kilns

    Institute of Scientific and Technical Information of China (English)

    YE Guotian; XU Yanqing

    2002-01-01

    ZrO2-containing refractories have been increasingly used for cement rotary kilns. This paper discusses how the properties and performance of ZrO2-containing. Refractories are inwroved in terms of chemical attack resistance, thermal shock resistance, thermal conductivity and mechanical stress.

  19. Abrasion Resistant Refractory Materials GB/T 23294-2009

    Institute of Scientific and Technical Information of China (English)

    Yu Lingyuan

    2009-01-01

    @@ 1 Scope This standard specifies the definition, classification, technical requirements, test methods, quality appraisal procedure, packing, marking, transportation, storage, and quality certificate of abrasion resistant refractory materials. This standard is applicable to abrasion resistant refractory materials for circulating fluidized bed boilers, daily waste incinerator, industrial waste incinerator, medical waste incinerator, ordinary solid waste incinerator, hazardous waste incinerator, etc.

  20. Bortezomib for refractory antibody-mediated cardiac allograft rejection.

    Science.gov (United States)

    Eckman, Peter M; Thorsgard, Marit; Maurer, David; Kim, Youngki; Alloway, Rita R; Woodle, E Steve

    2009-01-01

    This experience demonstrates that a bortezomib-based regimen provided effective therapy for late, refractory AMR in an adult heart transplant recipient and was well tolerated. This remarkably positive experience despite the refractory nature of the AMR episode argues strongly for continued evaluation of bortezomib use in this patient population.

  1. Thirty Years' Reform and Development in China's Refractories Industry

    Institute of Scientific and Technical Information of China (English)

    XU Dianli; CHEN Jianxiong

    2009-01-01

    @@ 1 Development of Refractories Industry Since the People's Republic of China Founded Refractories is mainly used in high temperature industries,such as metallurgy,building materials,nonferrous,chemical,mechanical,electric power industries,which is the important fundamental material for high temperature industries.

  2. Intraepithelial lymphocytes in refractory celiac disease : lost in transition

    NARCIS (Netherlands)

    Schmitz, Frederike

    2014-01-01

    Refractory coeliac disease type II (RCDII) is a severe complication of coeliac disease. Whereas celiac disease can successfully be treated by the strict avoidance of gluten, refractory celiac patients show no remission despite a gluten-free diet. The pathology of RCDII is only partially understood,

  3. Intraepithelial lymphocytes in refractory celiac disease : lost in transition

    NARCIS (Netherlands)

    Schmitz, Frederike

    2014-01-01

    Refractory coeliac disease type II (RCDII) is a severe complication of coeliac disease. Whereas celiac disease can successfully be treated by the strict avoidance of gluten, refractory celiac patients show no remission despite a gluten-free diet. The pathology of RCDII is only partially understood,

  4. F-Alloy: An Alloy Based Model Transformation Language

    OpenAIRE

    Gammaitoni, Loïc; Kelsen, Pierre

    2015-01-01

    Model transformations are one of the core artifacts of a model-driven engineering approach. The relational logic language Alloy has been used in the past to verify properties of model transformations. In this paper we introduce the concept of functional Alloy modules. In essence a functional Alloy module can be viewed as an Alloy module representing a model transformation. We describe a sublanguage of Alloy called F-Alloy that allows the specification of functional Alloy modules. Module...

  5. PLUTONIUM-THORIUM ALLOYS

    Science.gov (United States)

    Schonfeld, F.W.

    1959-09-15

    New plutonium-base binary alloys useful as liquid reactor fuel are described. The alloys consist of 50 to 98 at.% thorium with the remainder plutonium. The stated advantages of these alloys over unalloyed plutonium for reactor fuel use are easy fabrication, phase stability, and the accompanying advantuge of providing a means for converting Th/sup 232/ into U/sup 233/.

  6. Mechanical properties of 50Molybdenum-50Rhenium alloys and their assembly by spinal muscular atrophy

    Science.gov (United States)

    Xu, Jianhui

    This study is concerned with the deformation and fracture behaviors, especially strain-rate effect on plasticity in tensile tests, of two 50Mo-50Re alloys at strain rates ranging from 10-6 s-1 to 1 s-1 at room temperature in air. Metallographic observations of the 50Mo-50Re alloys before and after tensile deformation were conducted to understand the relationships among mechanical properties, microstructure and strain rate in these alloys. Understanding the strain-rate effect on mechanical properties of 50Mo-50Re alloys is important for optimizing forming operations, especially sheet forming, of these alloys, which are often used in cathode and aerospace applications. An anomalous strain-rate effect on ductility was observed in the 50Mo-50Re alloys. Ductility was significantly increased by increasing the strain rate from 10-6 s-1 to 1 s-1 in the fully-recrystallized and recovery heat-treated 50Mo-50Re alloys in tension at room temperature. At a low strain rate, fracture was predominantly brittle, while it was more ductile at higher stain rates. At a low strain rate, secondary cracks initiated at grain boundaries and triple junctions were observed in these alloys, which suggested that significant stress concentration was generated by tensile plastic deformation in the vicinity of grain boundaries, especially triple junctions. Electron backscatter diffraction experiments revealed that there was strain concentration at grain boundaries and their triple junctions during tensile deformation in these alloys. The decrease in ductility at low strain rates in the alloys was related to the possible interaction between dislocations and trace interstitial atoms (e.g., H, O, N and C) picked up during production of these alloys. This dissertation also reports the research efforts made to optimize small-scale resistance spot welding (SSRSW) of refractory alloy 50Mo-50Re thin sheet by adjusting seven important welding parameters, including hold time, electrode material, electrode

  7. From stellar nebula to planets: the refractory components

    CERN Document Server

    Thiabaud, Amaury; Alibert, Yann; Cabral, Nahuel; Leya, Ingo; Mezger, Klaus

    2013-01-01

    We computed the abundance of refractory elements in planetary bodies formed in stellar systems with solar chemical composition by combining models for chemical composition and planet formation. We also consider the formation of refractory organic compounds, which have been ignored in previous studies on this topic. We used the commercial software package HSC Chemistry in order to compute the condensation sequence and chemical composition of refractory minerals incorporated into planets. The problem of refractory organic material is approached with two distinct model calculations: the first considers that the fraction of atoms used in the formation of organic compounds is removed from the system (i.e. organic compounds are formed in the gas phase and are nonreactive); and the second assumes that organic compounds are formed by the reaction between different compounds that had previously condensed from the gas phase. Results show that refractory material represents more than 50 wt % of the mass of solids accret...

  8. Diagnosis and Treatment of Refractory Gastroesophageal Reflux Disease (GERD

    Directory of Open Access Journals (Sweden)

    Selfie

    2015-12-01

    Full Text Available Gastroesophageal reflux disease (GERD was a damage in mucosal layer caused by gastric acid reflux. GERD was found about 10-20% in Western Countries and less in Asia, about 2,6-6,7%. Among different type of GERD, refractory GERD was a problem found in daily clinical practice. This terminology was used in patients with regurgitation and heartburn symptoms which is not responsive to 8 weeks proton pump inhibitor (PPI therapy. There were several mechanisms underlying the etiology and pathophysiology of refractory GERD. In general, refractory GERD diagnosis was based on clinical findings, objective endoscopic examination, ambulatory reflux monitoring, and response to antiacid-secretion therapy. Reevaluation of patients compliance should be the first step in refractory GERD management. A further treatment strategies could be started, consist of medical and surgical therapies. A basic clinical knowledge of refractory GERD would help clinician in deciding the best approach for diagnosis and therapy.

  9. High temperature strain of metals and alloys. Physical fundamentals

    Energy Technology Data Exchange (ETDEWEB)

    Levitin, V. [National Technical Univ., Zaporozhye (Ukraine)

    2006-07-01

    The author shows how new in-situ X-ray investigations and transmission electron microscope studies lead to novel explanations of high-temperature deformation and creep in pure metals, solid solutions and super alloys. This approach is the first to find unequivocal and quantitative expressions for the macroscopic deformation rate by means of three groups of parameters: substructural characteristics, physical material constants and external conditions. Creep strength of the studied uptodate single crystal super alloys is greatly increased over conventional polycrystalline super alloys. The contents of this book include: macroscopic characteristics of strain at high temperatures; experimental equipment and technique of in situ X-ray investigations; experimental data and structural parameters in deformed metals; sub-boundaries as dislocation sources and obstacles; the physical mechanism of creep and the quantitative structural model; simulation of the parameters evolution; system of differential equations; high-temperature deformation of industrial super alloys; single crystals of super alloys; effect of composition, orientation and temperature on properties; and creep of some refractory metals.

  10. Environmental protection to 922K (1200 F) for titanium alloys

    Science.gov (United States)

    Groves, M. T.

    1973-01-01

    Evaluations are presented of potential coating systems for protection of titanium alloys from hot-salt stress-corrosion up to temperatures of 755 K (900 F) and from oxidation embrittlement up to temperature of 922 K (1200 F). Diffusion type coatings containing Si, Al, Cr, Ni or Fe as single coating elements or in various combinations were evaluated for oxidation protection, hot-salt stress-corrosion (HSSC) resistance, effects on tensile properties, fatigue properties, erosion resistance and ballistic impact resistance on an alpha and beta phase titanium alloy (Ti-6Al-2Sn-4Zr-2Mo). All of the coatings investigated demonstrated excellent oxidation protectiveness, but none of the coatings provided protection from hot-salt stress-corrosion. Experimental results indicated that both the aluminide and silicide types of coatings actually decreased the HSSC resistance of the substrate alloy. The types of coatings which have typically been used for oxidation protection of refractory metals and nickel base superalloys are not suitable for titanium alloys because they increase the susceptibility to hot-salt stress-corrosion, and that entirely new coating concepts must be developed for titanium alloy protection in advanced turbine engines.

  11. Stimulus-dependent refractoriness in the Frankenhaeuser-Huxley model.

    Science.gov (United States)

    Morse, R P; Allingham, D; Stocks, N G

    2015-10-07

    Phenomenological neural models, such as the leaky integrate-and-fire model, normally have a fixed refractory time-course that is independent of the stimulus. The recovery of threshold following an action potential is typically based on physiological experiments that use a two-pulse paradigm in which the first pulse is suprathreshold and causes excitation and the second pulse is used to determine the threshold at various intervals following the first. In such experiments, the nerve is completely unstimulated between the two pulses. This contrasts the receptor stimuli in normal physiological systems and the electrical stimuli used by cochlear implants and other neural prostheses. A numerical study of the Frankenhaeuser-Huxley conductance-based model of nerve fibre was therefore undertaken to investigate the effect of stimulation on refractoriness. We found that the application of a depolarizing stimulus during the later part of what is classically regarded as the absolute refractory period could effectively prolong the absolute refractory period, while leaving the refractory time-constants and other refractory parameters largely unaffected. Indeed, long depolarizing pulses, which would have been suprathreshold if presented to a resting nerve fibre, appeared to block excitation indefinitely. Stimulation during what is classically regarded as the absolute refractory period can therefore greatly affect the temporal response of a nerve. We conclude that the classical definition of absolute refractory period should be refined to include only the initial period following an action potential when an ongoing stimulus would not affect threshold; this period was found to be about half as long as the classical absolute refractory period. We further conclude that the stimulus-dependent nature of the relative refractory period must be considered when developing a phenomenological nerve model for complex stimuli.

  12. NOvel Refractory Materials for High Alkali, High Temperature Environments

    Energy Technology Data Exchange (ETDEWEB)

    Hemrick, J.G.; Griffin, R. (MINTEQ International, Inc.)

    2011-08-30

    Refractory materials can be limited in their application by many factors including chemical reactions between the service environment and the refractory material, mechanical degradation of the refractory material by the service environment, temperature limitations on the use of a particular refractory material, and the inability to install or repair the refractory material in a cost effective manner or while the vessel was in service. The objective of this project was to address the need for new innovative refractory compositions by developing a family of novel MgO-Al2O3 spinel or other similar magnesia/alumina containing unshaped refractory composition (castables, gunnables, shotcretes, etc) utilizing new aggregate materials, bond systems, protective coatings, and phase formation techniques (in-situ phase formation, altered conversion temperatures, accelerated reactions, etc). This family of refractory compositions would then be tailored for use in high-temperature, highalkaline industrial environments like those found in the aluminum, chemical, forest products, glass, and steel industries. A research team was formed to carry out the proposed work led by Oak Ridge National Laboratory (ORNL) and was comprised of the academic institution Missouri University of Science and Technology (MS&T), and the industrial company MINTEQ International, Inc. (MINTEQ), along with representatives from the aluminum, chemical, glass, and forest products industries. The two goals of this project were to produce novel refractory compositions which will allow for improved energy efficiency and to develop new refractory application techniques which would improve the speed of installation. Also methods of hot installation were sought which would allow for hot repairs and on-line maintenance leading to reduced process downtimes and eliminating the need to cool and reheat process vessels.

  13. Advanced treatment of refractory organic pollutants in petrochemical industrial wastewater by bioactive enhanced ponds and wetland system.

    Science.gov (United States)

    Liu, Shuo; Ma, Qiusha; Wang, Baozhen; Wang, Jifu; Zhang, Ying

    2014-05-01

    A large-scale combined ponds-wetland system was applied for advanced treatment of refractory pollutants in petrochemical industrial wastewater. The system was designed to enhance bioactivity and biological diversity, which consisted of anaerobic ponds (APs), facultative ponds (FPs), aerobic pond and wetland. The refractory pollutants in the petrochemical wastewater to be treated were identified as alkanes, chloroalkanes, aromatic hydrocarbons, and olefins, which were significantly degraded and transformed along with the influent flowing through the enhanced bioactive ponds-wetland system. 8 years of recent operational data revealed that the average removal rate of stable chemical oxygen demand (COD) was 42.7 % and that influent COD varied from 92.3 to 195.6 mg/L. Final effluent COD could reach 65.8 mg/L (average). COD removal rates were high in the APs and FPs and accounted for 75 % of the total amount removed. This result indicated that the APs and FPs degraded refractory pollutants through the facilitation of bacteria growth. The changes in the community structures of major microbes were assessed by 16SrDNA-denaturing gradient gel electrophoresis. The same analysis was used to identify the main bacterial function for the removal of refractory pollutants in the APs and FPs. The APs and FPs displayed similar microbial diversities, and some of the identified bacteria degraded and removed refractory pollutants. The overall results proved the applicability, stability, and high efficiency of the ponds-wetland system with enhanced bioactivity in the advanced removal of refractory pollutants from petrochemical industrial wastewater.

  14. High strength alloys

    Science.gov (United States)

    Maziasz, Phillip James; Shingledecker, John Paul; Santella, Michael Leonard; Schneibel, Joachim Hugo; Sikka, Vinod Kumar; Vinegar, Harold J.; John, Randy Carl; Kim, Dong Sub

    2012-06-05

    High strength metal alloys are described herein. At least one composition of a metal alloy includes chromium, nickel, copper, manganese, silicon, niobium, tungsten and iron. System, methods, and heaters that include the high strength metal alloys are described herein. At least one heater system may include a canister at least partially made from material containing at least one of the metal alloys. At least one system for heating a subterranean formation may include a tublar that is at least partially made from a material containing at least one of the metal alloys.

  15. High strength alloys

    Energy Technology Data Exchange (ETDEWEB)

    Maziasz, Phillip James [Oak Ridge, TN; Shingledecker, John Paul [Knoxville, TN; Santella, Michael Leonard [Knoxville, TN; Schneibel, Joachim Hugo [Knoxville, TN; Sikka, Vinod Kumar [Oak Ridge, TN; Vinegar, Harold J [Bellaire, TX; John, Randy Carl [Houston, TX; Kim, Dong Sub [Sugar Land, TX

    2010-08-31

    High strength metal alloys are described herein. At least one composition of a metal alloy includes chromium, nickel, copper, manganese, silicon, niobium, tungsten and iron. System, methods, and heaters that include the high strength metal alloys are described herein. At least one heater system may include a canister at least partially made from material containing at least one of the metal alloys. At least one system for heating a subterranean formation may include a tubular that is at least partially made from a material containing at least one of the metal alloys.

  16. Talimogene Laherparepvec and Nivolumab in Treating Patients With Refractory Lymphomas or Advanced or Refractory Non-melanoma Skin Cancers

    Science.gov (United States)

    2017-06-30

    Adenoid Cystic Carcinoma; Adnexal Carcinoma; Apocrine Carcinoma; Eccrine Porocarcinoma; Extraocular Cutaneous Sebaceous Carcinoma; Hidradenocarcinoma; Keratoacanthoma; Malignant Sweat Gland Neoplasm; Merkel Cell Carcinoma; Microcystic Adnexal Carcinoma; NK-Cell Lymphoma, Unclassifiable; Non-Melanomatous Lesion; Paget Disease; Papillary Adenocarcinoma; Primary Cutaneous Mucinous Carcinoma; Refractory Anaplastic Large Cell Lymphoma; Refractory Cutaneous T-Cell Non-Hodgkin Lymphoma; Refractory Mature T-Cell and NK-Cell Non-Hodgkin Lymphoma; Refractory Mycosis Fungoides; Refractory T-Cell Non-Hodgkin Lymphoma; Sezary Syndrome; Signet Ring Cell Carcinoma; Skin Basal Cell Carcinoma; Skin Basosquamous Cell Carcinoma; Skin Squamous Cell Carcinoma; Spiradenocarcinoma; Squamous Cell Carcinoma of Unknown Primary Origin; Stage III Skin Cancer; Stage IV Skin Cancer; Sweat Gland Carcinoma; Trichilemmocarcinoma; Vulvar Squamous Cell Carcinoma

  17. Treatment of refractory organic pollutants in industrial wastewater by wet air oxidation

    Directory of Open Access Journals (Sweden)

    Mingming Luan

    2017-02-01

    Full Text Available Wet air oxidation (WAO is one of the most economical and environmentally-friendly advanced oxidation processes. It makes a promising technology for the treatment of refractory organic pollutants in industrial wastewaters. In wet air oxidation aqueous waste is oxidized in the liquid phase at high temperatures (125–320 °C and pressures (0.5–20 MPa in the presence of an oxygen-containing gas (usually air. The advantages of the process include low operating costs and minimal air pollution discharges. The present review is concerned about the literature published in the treatment of refractory organic pollutants in industrial wastewaters, such as dyes. Phenolics were taken as model pollutants in most cases. Reports on effect of treatment for the WAO of refractory organic pollutants in industrial wastewaters are reviewed, such as emulsified wastewater, TNT red water, etc. Discussions are also made on the mechanism and kinetics of WAO and main technical parameters influencing WAO. Finally, development direction of WAO is summed up.

  18. Multiscale Modeling of Grain Boundary Segregation and Embrittlement in Tungsten for Mechanistic Design of Alloys for Coal Fired Plants

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Jian; Tomar, Vikas; Zhou, Naixie; Lee, Hongsuk

    2013-06-30

    Based on a recent discovery of premelting-like grain boundary segregation in refractory metals occurring at high temperatures and/or high alloying levels, this project investigated grain boundary segregation and embrittlement in tungsten (W) based alloys. Specifically, new interfacial thermodynamic models have been developed and quantified to predict high-temperature grain boundary segregation in the W-Ni binary alloy and W-Ni-Fe, W-Ni-Ti, W-Ni-Co, W-Ni-Cr, W-Ni-Zr and W-Ni-Nb ternary alloys. The thermodynamic modeling results have been experimentally validated for selected systems. Furthermore, multiscale modeling has been conducted at continuum, atomistic and quantum-mechanical levels to link grain boundary segregation with embrittlement. In summary, this 3-year project has successfully developed a theoretical framework in combination with a multiscale modeling strategy for predicting grain boundary segregation and embrittlement in W based alloys.

  19. Biocompatibility of dental alloys

    Energy Technology Data Exchange (ETDEWEB)

    Braemer, W. [Heraeus Kulzer GmbH and Co. KG, Hanau (Germany)

    2001-10-01

    Modern dental alloys have been used for 50 years to produce prosthetic dental restorations. Generally, the crowns and frames of a prosthesis are prepared in dental alloys, and then veneered by feldspar ceramics or composites. In use, the alloys are exposed to the corrosive influence of saliva and bacteria. Metallic dental materials can be classified as precious and non-precious alloys. Precious alloys consist of gold, platinum, and small amounts of non-precious components such as copper, tin, or zinc. The non-precious alloys are based on either nickel or cobalt, alloyed with chrome, molybdenum, manganese, etc. Titanium is used as Grade 2 quality for dental purposes. As well as the dental casting alloys, high purity electroplated gold (99.8 wt.-%) is used in dental technology. This review discusses the corrosion behavior of metallic dental materials with saliva in ''in vitro'' tests and the influence of alloy components on bacteria (Lactobacillus casei and Streptococcus mutans). The test results show that alloys with high gold content, cobalt-based alloys, titanium, and electroplated gold are suitable for use as dental materials. (orig.)

  20. Refractoriness in sustained visuo-manual control: is the refractory duration intrinsic or does it depend on external system properties?

    Science.gov (United States)

    van de Kamp, Cornelis; Gawthrop, Peter J; Gollee, Henrik; Loram, Ian D

    2013-01-01

    Researchers have previously adopted the double stimulus paradigm to study refractoriness in human neuromotor control. Currently, refractoriness, such as the Psychological Refractory Period (PRP) has only been quantified in discrete movement conditions. Whether refractoriness and the associated serial ballistic hypothesis generalises to sustained control tasks has remained open for more than sixty years. Recently, a method of analysis has been presented that quantifies refractoriness in sustained control tasks and discriminates intermittent (serial ballistic) from continuous control. Following our recent demonstration that continuous control of an unstable second order system (i.e. balancing a 'virtual' inverted pendulum through a joystick interface) is unnecessary, we ask whether refractoriness of substantial duration (~200 ms) is evident in sustained visual-manual control of external systems. We ask whether the refractory duration (i) is physiologically intrinsic, (ii) depends upon system properties like the order (0, 1(st), and 2(nd)) or stability, (iii) depends upon target jump direction (reversal, same direction). Thirteen participants used discrete movements (zero order system) as well as more sustained control activity (1(st) and 2(nd) order systems) to track unpredictable step-sequence targets. Results show a substantial refractory duration that depends upon system order (250, 350 and 550 ms for 0, 1(st) and 2(nd) order respectively, n=13, p<0.05), but not stability. In sustained control refractoriness was only found when the target reverses direction. In the presence of time varying actuators, systems and constraints, we propose that central refractoriness is an appropriate control mechanism for accommodating online optimization delays within the neural circuitry including the more variable processing times of higher order (complex) input-output relations.

  1. Refractoriness in sustained visuo-manual control: is the refractory duration intrinsic or does it depend on external system properties?

    Directory of Open Access Journals (Sweden)

    Cornelis van de Kamp

    Full Text Available Researchers have previously adopted the double stimulus paradigm to study refractoriness in human neuromotor control. Currently, refractoriness, such as the Psychological Refractory Period (PRP has only been quantified in discrete movement conditions. Whether refractoriness and the associated serial ballistic hypothesis generalises to sustained control tasks has remained open for more than sixty years. Recently, a method of analysis has been presented that quantifies refractoriness in sustained control tasks and discriminates intermittent (serial ballistic from continuous control. Following our recent demonstration that continuous control of an unstable second order system (i.e. balancing a 'virtual' inverted pendulum through a joystick interface is unnecessary, we ask whether refractoriness of substantial duration (~200 ms is evident in sustained visual-manual control of external systems. We ask whether the refractory duration (i is physiologically intrinsic, (ii depends upon system properties like the order (0, 1(st, and 2(nd or stability, (iii depends upon target jump direction (reversal, same direction. Thirteen participants used discrete movements (zero order system as well as more sustained control activity (1(st and 2(nd order systems to track unpredictable step-sequence targets. Results show a substantial refractory duration that depends upon system order (250, 350 and 550 ms for 0, 1(st and 2(nd order respectively, n=13, p<0.05, but not stability. In sustained control refractoriness was only found when the target reverses direction. In the presence of time varying actuators, systems and constraints, we propose that central refractoriness is an appropriate control mechanism for accommodating online optimization delays within the neural circuitry including the more variable processing times of higher order (complex input-output relations.

  2. Refractory and super-refractory status epilepticus in adults: a 9-year cohort study.

    Science.gov (United States)

    Delaj, L; Novy, J; Ryvlin, P; Marchi, N A; Rossetti, A O

    2017-01-01

    While status epilepticus (SE) persisting after two antiseizure agents is called refractory (RSE), super-refractory status epilepticus (SRSE) defines SE continuing after general anaesthesia. Its prevalence and related clinical profiles have received limited attention, and most studies were restricted to intensive care facilities. We therefore aimed at describing RSE and SRSE frequencies and identifying associated clinical variables. Between 2006 and 2015, consecutive adult SE episodes were prospectively recorded in a registry. Occurrence of RSE and SRSE and their relationship to clinical variables of interest, including outcome, were analysed. Of 804 SE episodes, 268 (33.3%) were RSE and 33 (4%) SRSE. Coma induction for SE treatment occurred in 79 (9.8%) episodes. Severe consciousness impairment (OR 1.67; 95% CI 1.24-2.46; P = 0.001), increasing age (OR 1.01, 95% CI 1.01-1.02), and lack of remote symptomatic SE aetiology (OR 0.48; 95% CI 0.32-0.72) were independently associated with RSE, while severe consciousness impairment (OR 4.26; 95% CI 1.44-12.60) and younger age (OR 0.96; 95% CI 0.95-0.99) correlated with SRSE; however, most SRSE episodes were not predicted by these variables. Mortality was 15.5% overall, higher in RSE (24.5%) and SRSE (37.9%) than in non-refractory SE (9.8%) (P < 0.001). Super-refractory status epilepticus appears clearly less prevalent in this cohort than previously reported, probably as it is not restricted to intensive care unit. SRSE emerges in younger patients with marked consciousness impairment, pointing to the underlying severe clinical background, but these variables do not predict most SRSE developments. There is currently a knowledge gap for prediction of SRSE occurrence that needs to be filled. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. The androgen receptor in hormone-refractory prostate cancer

    Institute of Scientific and Technical Information of China (English)

    Hai-Lei Mao; Zhi-Qi Zhu; Charlie Degui Chen

    2009-01-01

    Advanced prostate cancer is responsive to hormone therapy that interferes with androgen receptor (AR) signalling.However,the effect is short-lived,as nearly all tumours progress to a hormone-refractory (HR) state,a lethal stage of the disease.Intuitively,the AR should not be involved because hormone therapy that blocks or reduces AR activity is not effective in treating HR turnouts.However,there is still a consensus that AR plays an essential role in HR prostate cancer (HRPC) because AR signalling is still functional in HR tumours.AR signalling can be activated in HR turnouts through several mechanisms.First,activation of intracellular signal transduction pathways can sensitize the AR to castrate levels of androgens.Also,mutations in the AR can change AR ligand specificity,thereby allowing it to be activated by non-steroids or anti-androgens.Finally,overexpression of the wild-type AR sensitizes itself to low concentrations of androgens.Therefore,drugs targeting AR signalling could still be effective in treating HRPC.

  4. Two cases of refractory polymyositis accompanied with steroid myopathy.

    Science.gov (United States)

    Izumi, Yasumori; Miyashita, Taiichiro; Kitajima, Tsubasa; Yoshimura, Shunsuke; Takeoka, Atsushi; Eguchi, Katsumi; Motomura, Masakatsu; Kawakami, Atsushi; Migita, Kiyoshi

    2015-01-01

    Polymyositis (PM) is an inflammatory muscle disease characterized by chronic inflammation in skeletal muscle. Although most patients with PM respond to corticosteroids, some cases show an unsatisfactory response and other therapeutic options must be considered. Furthermore, glucocorticosteroid (GC) toxicity leads to a significant disability known as steroid myopathy, particularly in elderly patients. Here we report two patients with refractory PM. Combined treatment with high-dose GCs, tacrolimus, and intravenous immunoglobulin resulted in beneficial effects against myositis. However, muscle weakness and the disability progressed due to steroid myopathy, and subsequent oral intake became impossible because of swallowing disturbance in these two patients. Nutritional intervention, including branched-chain amino acids (BCAAs) and rehabilitation, was undertaken in addition to treatment against myositis. These treatments finally improved the muscle weakness and activities of daily living, and the two patients were discharged after recovery. The high-dose GC treatment caused elevation of serum levels of amino acids, including BCAAs, but these amino acids subsequently declined during BCAA replacement therapy. These findings suggest that the catabolic effects of the glucocorticoid treatment impair the balance of amino acids, including BCAAs, within the muscle, leading to steroid myopathy.

  5. Ozonation of refractory chemicals in leachate with hydrogen peroxide

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Nearly 97% of organic chemicals in Hong Kong leachatecould be effectively removed by the UASB(upflow anaerobic sludgeblanket) process followed by the Fenton coagulation. The COD ofleachate was lowered from an average of 12900 mg/L to 1440 mg/hafter the UASB treatment, and was further lowered to 394 mg/L afterthe Fenton coagulation. The remaining refractory residues could befurther removed by ozonation with the addition of H2O2. Theozonation for the supernatant of the Fenton coagulation was mosteffective at pH 7-8, with the addition of 300 mg/L of H2O2, and 30min of reaction. The final effluent contained only 85 mg/L of CODand l0 mg/L of BOD5. On the other hand, direct ozonation of UASBeffluent lowered the COD to 905 mg/L and BOD5 to l03 mg/L.Ozonation improved the biodegradability of the organic residues,and also converted part of organic-N in the leachate into NH3-N andNO3--N.

  6. Alemtuzumab in refractory Sézary syndrome*

    Science.gov (United States)

    Reifs, Carmen María Alcántara; Salido-Vallejo, Rafael; Garnacho-Saucedo, Gloria María; la Corte-Sánchez, Sofía De; González-Menchen, Alberto; García-Nieto, Antonio Vélez

    2016-01-01

    Sézary syndrome is a primary cutaneous T-cell lymphoma characterized by the triad of erythroderma, lymphadenopathy and circulating atypical cells. The emergence of new molecular targets has enabled the development of drugs such as alemtuzumab, an anti-CD52 monoclonal antibody, which has shown promising results in the treatment of this entity. We report the case of a 70-year-old male with refractory Sézary syndrome in whom treatment with alemtuzumab achieved an 80% skin lesion clearance with complete haematologic and radiologic response. The treatment was discontinued after 4 months due to adverse effects, with the patient showing a sustained response without disease progression after 13 months of follow-up. PMID:27828640

  7. Hypothermia for pediatric refractory status epilepticus.

    Science.gov (United States)

    Guilliams, Kristin; Rosen, Max; Buttram, Sandra; Zempel, John; Pineda, Jose; Miller, Barbara; Shoykhet, Michael

    2013-09-01

    Refractory status epilepticus (RSE) is a life-threatening emergency, demonstrating, by definition, significant pharmacoresistance. We describe five cases of pediatric RSE treated with mild hypothermia. Retrospective chart review was performed of records of children who received hypothermia for RSE at two tertiary-care pediatric hospitals between 2009 and 2012. Five children with RSE received mild hypothermia (32-35°C). Hypothermia reduced seizure burden during and after treatment in all cases. Prior to initiation of hypothermia, four children (80%) received pentobarbital infusions to treat RSE, but relapsed after pentobarbital discontinuation. No child relapsed after treatment with hypothermia. One child died after redirection of care. Remaining four children were discharged. This is the largest pediatric case series reporting treatment of RSE with mild hypothermia. Hypothermia decreased seizure burden during and after pediatric RSE and may prevent RSE relapse. Wiley Periodicals, Inc. © 2013 International League Against Epilepsy.

  8. Iron-Refractory Iron Deficiency Anemia

    OpenAIRE

    Ebru Yılmaz Keskin; İdil Yenicesu

    2015-01-01

    Demir, oksijenin taşınması, DNA sentezi ve hücre çoğalması gibi çeşitli biyolojik reaksiyonlar için vazgeçilmez olduğundan, yaşam için zorunludur. Demir metabolizması ve bu elementin düzenlenmesiyle ilgili bilgilerimiz, son yıllarda belirgin şekilde değişmiştir. Demir metabolizması ile ilgili yeni bozukluklar tanımlanmış ve demirin başka bozuklukların kofaktörü olduğu anlaşılmaya başlamıştır. Hemokromatozis ve demir tedavisine dirençli demir eksikliği anemisi (IRIDA; “iron-refractory iron def...

  9. Ketamine Infusions for Treatment Refractory Headache.

    Science.gov (United States)

    Pomeroy, Jared L; Marmura, Michael J; Nahas, Stephanie J; Viscusi, Eugene R

    2017-02-01

    Management of chronic migraine (CM) or new daily persistent headache (NDPH) in those who require aggressive outpatient and inpatient treatment is challenging. Ketamine has been suggested as a new treatment for this intractable population. This is a retrospective review of 77 patients who underwent administration of intravenous, subanesthetic ketamine for CM or NDPH. All patients had previously failed aggressive outpatient and inpatient treatments. Records were reviewed for patients treated between January 2006 and December 2014. The mean headache pain rating using a 0-10 pain scale was an average of 7.1 at admission and 3.8 on discharge (P ketamine well. A number of adverse events were observed, but very few were serious. Subanesthetic ketamine infusions may be beneficial in individuals with CM or NDPH who have failed other aggressive treatments. Controlled trials may confirm this, and further studies may be useful in elucidating more robust benefit in a less refractory patient population. © 2016 American Headache Society.

  10. Electrochemical Corrosion of Carbon—Containing Refractories

    Institute of Scientific and Technical Information of China (English)

    CHENZhao-you

    1994-01-01

    The electrochemical examination on the cor-rosion of carbon or carbon containing refractiories at molten slag-liquid interface has been carried out.The electromotive force(E.M.F)of cells with different molten slags:C|molten slag | Fe at elevated temperatures has been measured by means of potentiometer and it is in the range from 250 to 450mV .It is found that the carbon electrode in these cells is anode and whn a counter E.M.F.is applied externally to the cel,the corrosion of carbon electrode will be sup-pressed entirely.Test results show that the local corrosion of carbon containing refractories at slag-metal interface is mainly caused by the mechanism of electrochemical corrosion.

  11. Greater omentum in reconstruction of refractory wounds

    Institute of Scientific and Technical Information of China (English)

    沈余明; 沈祖尧

    2003-01-01

    Objective: To evaluate the clinical efficacy of greater omentum in reconstruction of refractory wounds. Methods: From August 1988 to May 2001, 20 patients with refractory wound underwent pedicle or microvascular free transfer of the greater omentum. Indications of surgery were electrical injury of the wrist and hand in 9 patients, electrical injury of the scalp and cranial bones in 3, avulsion injury of the scalp in 2, radiation-related ulcer of the chest wall in 2, ulcer and osteomyelitis following resection of the sternum sarcoma in 1, electrical injury of the abdomen in 1, bone and soft tissue defects following compound fracture of the leg in 1, and extensive scar and ulcer of the leg and footdrop following trauma in 1. Severe infection and extensive tissue necrosis were present prior to surgical operation in 12 patients. Eleven patients were treated with pedicled omental flaps, and 9 patients with free omental flaps. The size of the omental flaps ranged from 20 cm×12 cm to 38 cm×23 cm. Results: All the omental flaps survived. Healing at the first intention of the wounds was achieved in 17 cases. The on-top skin grafts resulted in partial necrosis of lipid liquefaction developed in the omentum and healed with dressing change in 2 cases. A sinus tract of osteomyelitis occurred in one case and healed after delayed excision of the necrosed bone. Follow-up study of all cases from 3 to 24 months showed no recurrent wounds and post-operative abdominal complication. Recovery with acceptable appearance and restoration of function was satisfactory. Conclusions: Greater omentum provides a well-vascularized tissue with lymphatic ducts for wound coverage. It has strong resistance against infection. It is very malleable and can be molded easily. Therefore it is an ideal tissue in filling cavities and repairing defects, especially in covering large and irregular defects that can not be treated with skin or muscle flaps.

  12. Pegloticase: in treatment-refractory chronic gout.

    Science.gov (United States)

    Lyseng-Williamson, Katherine A

    2011-11-12

    Intravenous pegloticase offers a novel approach to treating chronic gout refractory to conventional therapy. Pegloticase is a recombinant polyethylene glycol-conjugated form of uricase (a uric acid-specific enzyme lacking in humans) that catalyses the oxidation of uric acid to allantoin. In randomized, placebo-controlled, double-blind, 6-month, phase III trials, intravenous pegloticase 8 mg every 2 or 4 weeks provided sustained reductions in plasma uric acid levels to less than the therapeutic target of 6 mg/dL in a substantial proportion of patients with chronic gout who were refractory to, or intolerant of, conventional urate-lowering therapy. Pegloticase 8 mg every 2 weeks was associated with disease-modifying benefits relative to placebo, as shown by significant improvements from baseline in tophi resolution, frequency of gout flares and tender joint count, and clinically relevant and statistically significant improvements from baseline in health-related quality-of-life parameters related to disability, pain and physical function. Pegloticase 8 mg every 4 weeks was also significantly more effective than placebo with regard to most, but not all, of these endpoints. Preliminary data from an open-label extension of the phase III trials indicate that long-term treatment with pegloticase 8 mg every 2 or 4 weeks may maintain plasma uric acid normalization in patients who experienced a sustained uric acid response during the phase III trials. The most common serious adverse events associated with pegloticase are gout flares, infusion reactions and anaphylaxis. In addition, exacerbation of pre-existing congestive heart failure was reported in 2% of patients receiving pegloticase 8 mg every 2 weeks in the phase III trials.

  13. Esquizofrenia refratária Refractory schizophrenia

    Directory of Open Access Journals (Sweden)

    Helio Elkis

    2007-10-01

    Full Text Available OBJETIVO: O propósito deste artigo é o de revisar vários aspectos da esquizofrenia refratária levando em conta questões relacionadas à definição, aspectos clínicos, correlatos psicobiológicos, tratamentos farmacológicos e não farmacológicos, assim como preditores de resposta terapêutica. MÉTODO: Pesquisa no Medline, assim como artigos dos autores. RESULTADOS E CONCLUSÕES: Pelo menos um terço dos pacientes com esquizofrenia são refratários a tratamento com antipsicóticos e as evidências apontam a clozapina em monoterapia como a principal opção nesses casos. A politerapia com antipsicóticos não tem apoio em evidências. Ensaios clínicos recentes mostraram que a potencialização da clozapina com outros antipsicóticos não é superior ao placebo.OBJECTIVE: The aim of the present paper is to review the various aspects of refractory schizophrenia regarding issues such as definitions, clinical aspects, psychobiological correlates, pharmacological and non-pharmacological treatment options and predictors of treatment response. METHOD: Medline search as well as articles of the authors. RESULTS AND CONCLUSIONS: Refractory schizophrenia affects at least one third of patients with schizophrenia and the best evidence shows that is monotherapy with clozapine remains the mainstay for the treatment of such condition. Antipsychotic polipharmacy is not supported by current evidence and recent clinical trials have shown that clozapine augmentation with antipsychotics has no benefit over placebo.

  14. Brain stimulation for treatment of refractory epilepsy

    Institute of Scientific and Technical Information of China (English)

    GE Yan; HU Wei; LIU Chong; ZHANG Jian-guo; MENG Fan-gang

    2013-01-01

    Objective We review the targets of the deep brain and the responsive neurostimulation system (RNS) to identify the best optimal stimulation parameters and the best mode of stimulation,whether cyclical,continuous,or smarter.Data sources This review is based on data obtained from published articles from 1950 to 2013.To perform the PubMed literature search,the following keywords were input:deep brain stimulation (DBS),RNS,and refractory epilepsy.Study selection Articles containing information related to brain stimulation or RNS for the treatment of refractory epilepsy were selected.Results The currently available treatment options for those patients who resist multiple antiepileptic medications and surgical procedures include electric stimulation,both direct and indirect,of brain nuclei thought to be involved in epileptogenesis.The number of potential targets has increased over the years to include the anterior nucleus of the thalamus,the centromedian nucleus of the thalamus,the hippocampus,the subthalamic nucleus,the caudate nucleus,and the cerebellum,among others.The results of a randomized controlled trial and the RNS trial were published to reveal the effectiveness.Conclusions Although statistically significant reductions in seizures have been observed using several different stimulation techniques,including vagus nerve stimulation,DBS,and RNS,these effects are currently only palliative and do not approach the efficacy comparable with that seen in resection in appropriately selected patients.More research is needed to determine optimal stimulation targets and techniques as well as to determine which epilepsy patients will benefit most from this technology.

  15. Modifying structure and properties of nickel alloys by nanostructured composite powders

    Science.gov (United States)

    Cherepanov, A. N.; Ovcharenko, V. E.; Liu, G.; Cao, L.

    2015-01-01

    The article presents the results of an experimental study of the influence of powder nanomodifiers of refractory compounds on the mechanical properties, macro- and microstructure of heat-resistant alloys ZhS-6K and Inconel 718. It is shown that the introduction of nanomodifiers into the melt leads to the refinement of the alloy structure: the average grain size decreases 1.5-2 times, and their morphology becomes similar to equiaxial at significant reduction of the particle size in the carbide phase. The service life of ZhS-6K alloy under cyclic loading at 600°C increases 2.7 times, and at 975 °C by 40 %, and relative elongation increases more than twice. The mechanical properties of Inconel 718 significantly increase: long-term strength at 650 °C increases 1.5-2 times, and the number of cycles before the collapse at 482 °C grows more than three times. It has been found out that addition of nanomodifiers to the melt, in alloys, forms clusters of particles of refractory compounds at borders and joints of the formed grain structure that may help slowing down the processes of recrystallization (prevents the increase in the size of the contacting grains by their associations) and stabilizes the strength properties of the alloys at higher temperatures.

  16. TA [B] Predicting Microstructure-Creep Resistance Correlation in High Temperature Alloys over Multiple Time Scales

    Energy Technology Data Exchange (ETDEWEB)

    Tomar, Vikas [Purdue Univ., West Lafayette, IN (United States)

    2017-03-06

    DoE-NETL partnered with Purdue University to predict the creep and associated microstructure evolution of tungsten-based refractory alloys. Researchers use grain boundary (GB) diagrams, a new concept, to establish time-dependent creep resistance and associated microstructure evolution of grain boundaries/intergranular films GB/IGF controlled creep as a function of load, environment, and temperature. The goal was to conduct a systematic study that includes the development of a theoretical framework, multiscale modeling, and experimental validation using W-based body-centered-cubic alloys, doped/alloyed with one or two of the following elements: nickel, palladium, cobalt, iron, and copper—typical refractory alloys. Prior work has already established and validated a basic theory for W-based binary and ternary alloys; the study conducted under this project extended this proven work. Based on interface diagrams phase field models were developed to predict long term microstructural evolution. In order to validate the models nanoindentation creep data was used to elucidate the role played by the interface properties in predicting long term creep strength and microstructure evolution.

  17. Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Kouvetakis, John

    2013-01-03

    The project addressed the need for improved multijunction solar cells as identified within the Solar America Initiative program. The basic Ge/InGaAs/InGaP triple-junction structure that has led to record commercial efficiencies remains unoptimized due to excess current in the germanium component. Furthermore, its deployment cannot be scaled up to terawatt-level applications due to bottlenecks related to germanium's cost and abundance. The purpose of the program was to explore new strategies developed at Arizona State University to deposit germanium films on much cheaper silicon substrates, largely eliminating the germanium bottleneck, and at the same time to develop new materials that should lead to an improvement in multijunction efficiencies. This included the ternary alloy SiGeSn, which can be inserted as a fourth junction in a Ge/SiGeSn/InGaAs/InGaP structure to compensate for the excess current in the bottom cell. Moreover, the possibility of depositing materials containing Sn on Si substrates created an opportunity for replacing the bottom Ge cell with a GeSn alloy, which, combined with new III-V alloys for the top cells, should enable 4-junction structures with perfectly optimized band gaps. The successes of the program, to be described below, has led to the developments of new strategies for the growth of high-quality germanium films on Si substrates and to a widespread recognition that SiGeSn is likely to play a significant role in future generations of high-efficiency devices, as demonstrated by new research and intellectual property efforts by major US industrial players.

  18. Fabrication and Characterization of Brazed Joints for SiC-Metallic Systems Utilizing Refractory Metals

    Science.gov (United States)

    Coddington, Bryan; Asthana, Rajiv; Halbig, Michael C.; Singh, M.

    2011-01-01

    Metal to ceramic joining plays a key role for the integration of ceramics into many nuclear, ground and aero based technologies. In order to facilitate these technologies, the active metal brazing of silicon carbide (CVD beta-SiC, 1.1 mm thick, and hot-pressed alpha-SiC, 3 mm thick) to the refractory metals molybdenum and tungsten using active braze alloys was studied. The joint microstructure, composition, and microhardness were evaluated by optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and Knoop hardness testing. The braze alloys, Cusil-ABA, Ticusil and Copper-ABA, all formed sound joints with excellent wetting and chemical bonding with the SiC substrate. Despite the close thermal expansion match between the metal substrates and SiC, hairline cracks formed in alpha-SiC while beta-SiC showed no signs of residual stress cracking. The use of ductile interlayers to reduce the effect from residual stresses was investigated and joints formed with copper as an interlayer produced crack free systems utilizing both CVD and hot-pressed SiC.

  19. High-Density Infrared Surface Treatments of Refractories

    Energy Technology Data Exchange (ETDEWEB)

    Tiegs, T.N.

    2005-03-31

    Refractory materials play a crucial role in all energy-intensive industries and are truly a crosscutting technology for the Industries of the Future (IOF). One of the major mechanisms for the degradation of refractories and a general decrease in their performance has been the penetration and corrosion by molten metals or glass. Methods and materials that would reduce the penetration, wetting, and corrosive chemistry would significantly improve refractory performance and also maintain the quality of the processed liquid, be it metal or glass. This report presents the results of an R&D project aimed at investigating the use of high-density infrared (HDI) heating to surface treat refractories to improve their performance. The project was a joint effort between Oak Ridge National Laboratory (ORNL) and the University of Missouri-Rolla (UMR). HDI is capable of heating the near-surface region of materials to very high temperatures where sintering, diffusion, and melting can occur. The intended benefits of HDI processing of refractories were to (1) reduce surface porosity (by essentially sealing the surface to prevent liquid penetration), (2) allow surface chemistry changes to be performed by bonding an adherent coating onto the underlying refractory (in order to inhibit wetting and/or improve corrosion resistance), and (3) produce noncontact refractories with high-emissivity surface coatings.

  20. Synthesis of Al/Al sub 3 Ti two-phase alloys by mechanical alloying

    Energy Technology Data Exchange (ETDEWEB)

    Srinivasan, S.; Chen, S.R.; Schwarz, R.B.

    1991-01-01

    We have mechanically alloyed mixtures of elemental powders to prepare fine-grain two-phase A1/A1{sub 3}Ti powders at the compositions A1-20at% Ti and Al-10at% Ti. Hexane was used to prevent agglomeration of the powder during MA. Carbon from the decomposition of the hexane was incorporated in the powder. It reacted with Ti to form a fine dispersion of carbides in the final hot-pressed compact. We consolidated the mechanically alloyed powders by hot-pressing. Yield strength and ductility were measured in compression. At 25{degree}C, the compressive yield strengths were 1.25 and 0.6 GPa for the A1-20at% Ti and Al-10at% Ti alloys, respectively. The ductility of the A1-10at% Ti alloy exceeded 20% for 25 < T < 500{degree}C. 25 refs., 6 figs.

  1. Development of an Electric induction furnace for heat treatment of ferrous and non-ferrous alloys

    OpenAIRE

    Ufuoma Peter Anaidhuno; Chinedum Ogonna Mgbemena

    2015-01-01

    A 3kg capacity Electric induction furnace with a power rating of 2500W for heat treatment of ferrous and non-ferrous alloys was developed. The furnace which is made from mild steel sheet was monolithically lined with fire clay refractories and designed to attain a temperature of 12000C on the automatic control panel. This project was primarily undertaken to build local capacity in foundry practice in Nigeria and to encourage the demonstration of fundamental foundry practice for undergradua...

  2. [Fever-induced refractory epileptic encephalopathy of children].

    Science.gov (United States)

    Sivkova, S N; Bogdanov, E I; Zaĭkova, F M; Morozova, E A; Aiupova, V A; Zabbarova, A T; Shaĭmardanova, R M

    2013-01-01

    Fever-induced refractory epileptic encephalopathy of school-age children is a rare epileptic syndrome that causes difficulties in diagnosis at the initial stage of disease. It is characterized by sudden onset with multifocal refractory status epilepticus in previously healthy children with normal development. Later, children suffer from resistant focal epilepsy in the combination with cognitive deficit and behavioral difficulties. Authors describe a clinical case of fever-induced refractory epileptic encephalopathy of school-age children in a child of 7 years old. Aspects of etiology, pathogenesis, clinical manifestation, differential diagnosis, treatment and prognosis of the disease are discussed.

  3. Successful treatment of severe refractory lupus hepatitis with mycophenolate mofetil.

    Science.gov (United States)

    Tagawa, Y; Saito, T; Takada, K; Kawahata, K; Kohsaka, H

    2016-04-01

    Systemic lupus erythematosus-related hepatitis, known as lupus hepatitis, is a rare manifestation of systemic lupus erythematosus, and is usually subclinical with mild abnormalities of serum liver enzymes. While cases with clinically significant and refractory lupus hepatitis are uncommon, treatment options for lupus hepatitis are to be established. Here, we report the case of a 45-year-old man with progressive lupus hepatitis accompanied by autoimmune haemolytic anaemia. Lupus hepatitis of this patient was refractory to tacrolimus, azathioprine and cyclophosphamide, but was successfully treated by mycophenolate mofetil. Mycophenolate mofetil might be an effective therapeutic option for refractory lupus hepatitis.

  4. Oxidation mechanisms for alloys in single-oxidant gases

    Energy Technology Data Exchange (ETDEWEB)

    Whittle, D.P.

    1981-03-01

    Scales formed on alloys invariably contain the alloy constituents in a ratio different from that in the alloy, owing to the differing thermodynamic tendencies of the alloy components to react with the oxidant and to differences in diffusion rates in scale and alloy phases. This complex interrelationship between transport rates and the thermodynamics of the alloy-oxidant system can be analyzed using multicomponent diffusion theory when transport-controlled growth of single or multi-layered scales occurs. In particular, the superimposition of the diffusion data on an isothermal section of the appropriate phase diagram indicates the likely morphologies of the reaction products, including the sequence of phases found in the scale, the occurrence of internal oxidation and the development of an irregular metal/scale interface. The scale morphologies on alloys are also time-dependent: there is an initial transient stage, a steady state period, and a final breakdown, the latter often related to mechanical influences such as scale adherence, spallation, thermal or mechanical stresses and void formation. Mechanical influences have a more devastating effect in alloy oxidation due to the changes in alloy surface composition during the steady state period.

  5. A new paradigm for heat treatment of alloys

    Energy Technology Data Exchange (ETDEWEB)

    Ustinovshikov, Y., E-mail: ust@ftiudm.ru

    2014-11-25

    Highlights: • The sign of the ordering energy in alloys varies with the temperature. • Each temperature of heating leads to formation of its characteristic microstructure. • Quenching of alloys is a totally unnecessary and useless operation. - Abstract: The article considers the consequences in the field of heat treatment of alloys that could follow the introduction of the concept of phase transition ordering-phase separation into common use. By example of the Fe{sub 50}Cr{sub 50} alloy, industrial carbon tool steel and Ni{sub 88}Al{sub 12} alloy, it is shown that this transition occurs at a temperature, which is definite for each system, that the change of the sign of the chemical interaction between component atoms reverses the direction of diffusion fluxes in alloys, which affects changes in the type of microstructures. The discovery of this phase transition dramatically changes our understanding of the solid solution, changes the ideology of alloy heat treatment. It inevitably leads to the conclusion about the necessity of carrying out structural studies with the help of TEM in order to adjust the phase diagrams of the systems where this phase transition has been discovered. Conclusions have been made that quenching of alloys from the so-called region of the solid solution, which is usually performed before tempering (aging) is a completely unnecessary and useless operation, that the final structure of the alloy is formed during tempering (aging) no matter what the structure was before this heat treatment.

  6. New developments in rapidly solidified magnesium alloys

    Energy Technology Data Exchange (ETDEWEB)

    Das, S.K. [Allied-Signal, Inc., Morristown, NJ (United States); Chang, C.F. [Allied-Signal, Inc., Morristown, NJ (United States); Raybould, D. [Allied-Signal, Inc., Morristown, NJ (United States); King, J.F. [Magnesium Elektron Ltd., Manchester (United Kingdom); Thistlethwaite, S. [Magnesium Elektron Ltd., Manchester (United Kingdom)

    1992-12-31

    In the present paper, we will examine the new developments in the rapidly solidified Mg-Al-Zn-Nd (EA55RS) alloy. We shall first briefly review the process scale-up currently employed for producing rapidly solidified magnesium alloys in large quantities, and then discuss the effect of billet size and processing parameters on the mechanical properties of various mill product forms such as extrusions and sheets. The superplastic behavior of EA55RS extrusions and rolled sheets are also discussed. Finally, some results on magnesium metal-matrix composites using rapidly solidified EA55RS matrix powders and SiC particulates are presented. (orig.)

  7. Studies of the AA2519 Alloy Hot Rolling Process and Cladding with EN AW-1050A Alloy

    Directory of Open Access Journals (Sweden)

    Płonka B.

    2016-03-01

    Full Text Available The objective of the study was to determine the feasibility of plastic forming by hot rolling of the AA2519 aluminium alloy sheets and cladding these sheets with a layer of the EN AW-1050A alloy. Numerous hot-rolling tests were carried out on the slab ingots to define the parameters of the AA2519 alloy rolling process. It has been established that rolling of the AA2519 alloy should be carried out in the temperature range of 400-440°C. Depending on the required final thickness of the sheet metal, appropriate thickness of the EN AW-1050A alloy sheet, used as a cladding layer, was selected. As a next step, structure and mechanical properties of the resulting AA2519 alloy sheets clad with EN AW-1050A alloy was examined. The thickness of the coating layer was established at 0,3÷0,5mm. Studies covered alloy grain size and the core alloy-cladding material bond strength.

  8. Catalyst Alloys Processing

    Science.gov (United States)

    Tan, Xincai

    2014-10-01

    Catalysts are one of the key materials used for diamond formation at high pressures. Several such catalyst products have been developed and applied in China and around the world. The catalyst alloy most widely used in China is Ni70Mn25Co5 developed at Changsha Research Institute of Mining and Metallurgy. In this article, detailed techniques for manufacturing such a typical catalyst alloy will be reviewed. The characteristics of the alloy will be described. Detailed processing of the alloy will be presented, including remelting and casting, hot rolling, annealing, surface treatment, cold rolling, blanking, finishing, packaging, and waste treatment. An example use of the catalyst alloy will also be given. Industrial experience shows that for the catalyst alloy products, a vacuum induction remelt furnace can be used for remelting, a metal mold can be used for casting, hot and cold rolling can be used for forming, and acid pickling can be used for metal surface cleaning.

  9. Compressive Creep and Thermophysical Performance of Mullite Refractories

    Energy Technology Data Exchange (ETDEWEB)

    Hemrick, JG

    2002-04-01

    Compressive creep testing of ten commercially available mullite refractories was performed at 1300-1450 C and at static stresses between 0.2-0.6 MPa. These refractories were examined because they are used in borosilicate glass furnace crowns and superstructures along with in sidewall applications. Additionally, despite their high cost ({approx}$500/ft{sup 3}) they are cheaper than other refractories such as chrome alumina ({approx}$3000/ft{sup 3}) or fusion-cast alumina ({approx}900/ft{sup 3}) which are used as replacements for traditional silica refractories in harsh oxy-fuel environments. The corrosion resistances of these ten materials were also evaluated. In addition, measurements were made that tracked their dimensional stability, phase content, microstructure, and composition as a function of temperature and time. The techniques used for these characterizations and their respective analyses are described. An intent of this study was to provide objective and factual results whose interpretations were left to the reader.

  10. Refractory Coated/Lined Low Density Structures Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation in this proposed effort is the development of refractory coated or lined low density structures. Lightweight structures are desirable for space...

  11. Fireclay Refractory Mortars GB/T 14982-2008

    Institute of Scientific and Technical Information of China (English)

    Zhang Xiaohui; Chai Junlan

    2009-01-01

    @@ 1 Scope This standard specifies the classification, techni-cal requirements, test methods, quality appraisal pro-cedure, packing, marking, transportation, storage and quality certificate of fireclay refractory mortars.

  12. High Alumina Refractory Mortars GB/T 2994-2008

    Institute of Scientific and Technical Information of China (English)

    Wang Jing; Chai Junlan

    2009-01-01

    @@ 1 Scope This standard specifies the classification, techni-cal requirements, test methods, quality appraisal pro-cedure, packing, marking, transportation, storage and quality certificate of high alumina refractory mortars.

  13. Refractory, Abrasive, and Other Industrial Minerals Operations - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer includes refractory, abrasive, and other industrial minerals operations in the United States. The data represent commodities covered by the Minerals...

  14. Refractory Gunning Material for Inner Lining Maintenance of Blast Furnace

    Institute of Scientific and Technical Information of China (English)

    Yu Lingyan; Peng Xigao

    2010-01-01

    @@ 1 Scope This standard specifies the term and definition,classification, technical requirements, test methods,quality appraisal procedures, packing, marking, transportation, storage, and quality certificate of refractory gunning material for inner lining maintenance of blast furnace .

  15. Fused Cast Alumina Refractory Products for Glass Tank Furnace

    Institute of Scientific and Technical Information of China (English)

    SHEN Keyin

    2006-01-01

    @@ 1 Subject and Scope The standard specifies the requirement, testing method, inspection rule and requirements for the labeling, packing, shipping and storing of the fused cast alumina refractory products for glass tanks.

  16. Effectiveness of botulinum toxin A in treatment of refractory erythromelalgia

    Directory of Open Access Journals (Sweden)

    Kuan-Hsiang Lin

    2013-05-01

    Full Text Available Erythromelalgia is characterized by intense burning pain, erythema, and heat in affected areas after precipitating factors such as warm temperature or stress. It is refractory to treatment in some situations. We describe a woman with adenosquamous cell carcinoma of the lung and medically refractory erythromelalgia. The symptoms of erythromelalgia presented as refractory to any medical treatment. Due to the unresponsive nature of her condition, botulinum toxin type A (onabotulinumtoxin A was injected over both of her cheeks, periodically for six cycles. Her symptoms responded dramatically to subcutaneous and intradermal injection of botulinum toxin type A. Repetitive injection demonstrated consistent and reproducible responses, and the efficacy was maintained for approximately 1 month. No adverse effects or complications were noted. Botulinum toxin type A might be safe and effective as an alternative treatment for refractory erythromelalgia, but further large-scale studies are required.

  17. High Alumina Refractory Bricks for Electric Arc Furnace Roofs

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ 1 Scope This standard specifies the sort, technical requirement, test method, inspection rules, marking, packing, transportation, storage and quality certification of high alumina refractory bricks for electric arc furnace roofs.

  18. Elderly woman with cerebrovascular accident and refractory arrhythmias.

    Science.gov (United States)

    Sethi, S K; Sarm, P S A

    2009-11-01

    Fatal bilateral cerebro-vascular accident with variable atrio-ventricular blocks, atrial fibrillation and refractory tachy-arrhythmias in a previously healthy 75-years-old hypertensive female is presented.

  19. Rituximab Efficacy during a Refractory Polyarteritis Nodosa Flare

    Directory of Open Access Journals (Sweden)

    Emmanuel Ribeiro

    2009-01-01

    Full Text Available Polyarteritis nodosa (PAN is a systemic vasculitis whose severe forms are treated with glucocorticoids and cyclophosphamide. Refractory patients are exposed to many complications, notably accelerated atherosclerosis. We report a case report of 71-year-old man followed for polyarteritis nodosa refractory to glucocorticoids and cyclosphosphamide. Systemic vasculitis relapses are followed to accelerated atherosclerosis: severe ischemic lesions led to amputation of lower limbs. Remission of refractory PAN is obtained with rituximab. Disappearance of biological inflammatory is allowed to regression of ischemic lesions in upper limbs. In this situation, we recommend a systematic vascular work-up for patients suffered from refractory vasculitis. On the other hand, therapeutic trials are needed to determine the real efficacy and place of rituximab in the treatment of polyarteritis nodosa.

  20. Recycling MgO-C refractory in electric arc furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Conejo, A.N. [Metallurgy Department, Morelia Technological Institute, Morelia (Mexico); Lule, R.G.; Lopez, F. [Process Engineering Department-Steelmaking Shop, Lazaro Cardenas City (Mexico); Rodriguez, R. [Refractories Department, Lazaro Cardenas City (Mexico)

    2006-11-15

    MgO-C refractory recycling from electric arc furnaces and ladle furnaces has been carried out during the melting of direct reduced iron (DRI). Metallurgical trials to define the effects of refractory recycling on energy consumption, melting time, flux consumption and refractory consumption are reported in this work. The method of preparation as well as the method of injection is also included in this study. Based on current results, the practice of recycling spent refractory is highly recommended. Visual inspection indicates the potential benefits in slag foaming which starts to form at the beginning of the heat thus allowing the use of full power transformer and in turn results in faster melting rates. (author)

  1. Coatability of cement clinker on basic refractories

    Science.gov (United States)

    Guo, Zongqi

    The aim of this work is to develop an effective and practicable method to evaluate the coatability of cement clinker on basic refractory bricks, susceptible to be translated in numbers. Determinations of the dominant influential factors, and assessment of reliability, as well as of coating mechanisms on different basic bricks, are to be tackled. Raw meal has been investigated in terms of chemical and phase compositions, particle size distribution, using DTA and TGA, as well as x-ray diffraction and microstructural analysis after heating at different temperatures. Raw meal calcinated at 1000°C for 4 hours contains plenty of free lime. Over 1350°C, most of liquid phases and belite C2S have formed. At 1450°C, there are still some clusters of free lime in clinker. Alite C 3S becomes dominant phase in clinker fired at temperature of 1550°C, with reduction of belite C2S and depletion of free lime. Samples of 50 x 50 x 60 mm are directly cut dry from available bricks (without water-cooling) and the sandwich is prepared using the cut surfaces. At least six pieces are needed to have three sandwiches for all tested brands of basic refractories. Mean value of the modulus of rupture obtained from three replicates is considered as representative of the adherence strength of the coating. Statistical process analysis was also used to plan and carry out experiments carefully so as to confirm repeatability and reproducibility of the sandwich protocol. Variability of +/-0.5 MPa is considered to be acceptable on a 5 MPa measured value. The following conclusions can be derived from the results: (1) The most significant effects on adherence strength are the compressive loads, the nature of the raw meal, the heating temperature and the holding time, ranked in the order of importance. (2) A ruggedness test indicates that the sandwich test is insensitive to minor changes, in holding time, paste thickness and mixing mode of the paste. (3) Adherence mechanism of cement clinker on doloma

  2. Modeling of High Temperature Oxidation Behavior of FeCrAl Alloy by using Artificial Neural Network

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Joon; Ryu, Ho Jin [KAIST, Daejeon (Korea, Republic of)

    2016-10-15

    Refractory alloys are candidate materials for replacing current zirconium-base cladding of light water reactors and they retain significant creep resistance and mechanical strength at high temperatures up to 1500 ℃ due to their high melting temperature. Thermal neutron cross sections of refractory metals are higher than that of zirconium, however the loss of neutron can be overcome by reducing cladding thickness which can be facilitated with enhanced mechanical properties. However, most refractory metals show the poor oxidation resistance at a high temperature. Oxidation behaviors of the various compositions of FeCrAl alloys in high temperature conditions were modeled by using Bayesian neural network. The automatic relevance determination (ARD) technique represented the influence of the composition of alloying elements on the oxidation resistance of FeCrAl alloys. This model can be utilized to understand the tendency of oxidation behavior along the composition of each element and prove the applicability of neural network modeling for the development of new cladding material of light water reactors.

  3. PLUTONIUM-ZIRCONIUM ALLOYS

    Science.gov (United States)

    Schonfeld, F.W.; Waber, J.T.

    1960-08-30

    A series of nuclear reactor fuel alloys consisting of from about 5 to about 50 at.% zirconium (or higher zirconium alloys such as Zircaloy), balance plutonium, and having the structural composition of a plutonium are described. Zirconium is a satisfactory diluent because it alloys readily with plutonium and has desirable nuclear properties. Additional advantages are corrosion resistance, excellent fabrication propenties, an isotropie structure, and initial softness.

  4. Refractory absence epilepsy associated with GLUT-1 deficiency syndrome.

    LENUS (Irish Health Repository)

    Byrne, Susan

    2011-05-01

    GLUT-1 deficiency syndrome (GLUT-1 DS) is a disorder of cerebral glucose transport associated with early infantile epilepsy and microcephaly. We report two boys who presented with refractory absence epilepsy associated with hypoglycorrhachia, both of whom have genetically confirmed GLUT-1 DS. We propose that these children serve to expand the phenotype of GLUT-1 DS and suggest that this condition should be considered as a cause of refractory absence seizures in childhood.

  5. Thoughts on Strategic Development of China's Refractories Industry

    Institute of Scientific and Technical Information of China (English)

    ZHONG Xiangchong

    2003-01-01

    For China' s refractories industry, the first two decades in the new century would be a period of structural optimization with reorganization of refractories enterprises,reconstruction of manufacturing plants and restructuring of product varieties. An important strategic measure should be to develop high quality synthetic raw materials and high performance functional products mainly based on our rich natural resources to cope with new demands of advanced high temperature technologies.

  6. New Applications of Some High Technologies i Refractories

    Institute of Scientific and Technical Information of China (English)

    WUYiquan; ZHANGYufeng; 等

    2001-01-01

    The potential applications of some high tenologies in refractories,such as,nanotechnology,in-situ synthesis,self-propagating high-temperature synthesis,functional gradient materials,computer assisted design and some new advanced refactories in Si-Al-O-N system are briefly described.The characteristics and preparation processes of these new refractories areintroduced,and the remaining problems awaiting effective solutions are pointed out .Some suggesions on future diection of research and development are fitly made.

  7. Salvage abdominal irradiation for refractory non-Hodgkin′s lymphoma

    Directory of Open Access Journals (Sweden)

    Akoum Riad

    2007-01-01

    Full Text Available Background: Abdominal irradiation, as a part of treatment, is often ignored in the management of refractory non-Hodgkin′s lymphoma (NHL. Objective: To evaluate the efficacy and the toxicity of this approach after failure of chemotherapy. Materials and Methods: 27 patients with intraabdominal lymphoma underwent salvage irradiation between 1982 and 2001. All patients were treated with a Cobalt-60 machine. The total dose administered to the abdomen was 18-20 Gy at the rate of 1.5-1.8 Gy per daily fraction, followed by a boost to gross disease up to 20 Gy. All patients had previously been heavily pretreated with chemotherapy. Fourteen patients, nine with follicular and five with diffuse lymphomas, had primary refractory tumors that had never achieved remission. Thirteen patients, six with follicular and seven with aggressive tumors, had refractory relapsed tumors after achieving one or more complete remissions. Results: The response rate was 77%. The median follow-up was 53 months. The 5-year and 10-year survival rates were 25 and 17%, respectively. The in-field and out-of-field recurrence rates were 22 and 33%, respectively. Survival rates were significantly better for patients with refractory relapse compared to those with primary refractory lymphoma (P < 0.01. There was no significant difference in terms of response, recurrence, or survival rates between follicular and aggressive types. Out-of-field recurrence occurred more frequently in initial stage III and IV disease. Toxic deaths occurred in three patients (11%. Conclusion: Salvage radiotherapy for refractory abdominal NHL is a feasible alternative for both follicular and diffuse subtypes and may provide significant palliation and prolongation of survival. It is less effective in patients with primary refractory NHL than in those with refractory relapsed NHL.

  8. Ketogenic diet in 3 cases of childhood refractory status epilepticus

    DEFF Research Database (Denmark)

    Sort, Rune; Born, Alfred P; Pedersen, Karen N.;

    2013-01-01

    Refractory status epilepticus (RSE) in children is associated with a significant risk of death or neurological morbidity. Recently attention has been drawn to the ketogenic diet (KD) as an acute treatment, as it has shown promise in controlling seizures in otherwise refractory status epilepticus...... in several cases. We have listed these and reviewed all cases of KD used in RSE at our centre. KD was given as 4:1 fat:carbohydrate-protein solution....

  9. Severe aortic coarctation in a patient with refractory hypertension

    OpenAIRE

    Hiram Tápanes Daumy

    2015-01-01

    Idiopathic hypertension is common in adults, and some patients are considered resistant or refractory to treatment. In such cases it is often associated with a patho-logical process which hinders its control, in spite of changes in lifestyle and the proper use of drugs. This article is about an adult female patient with refractory hypertension due to aortic coarctation. CT scan and angiographic images are shown.Key words: Hypertension, Treatment, Aortic coarctation

  10. NICKEL-BASE ALLOY

    Science.gov (United States)

    Inouye, H.; Manly, W.D.; Roche, T.K.

    1960-01-19

    A nickel-base alloy was developed which is particularly useful for the containment of molten fluoride salts in reactors. The alloy is resistant to both salt corrosion and oxidation and may be used at temperatures as high as 1800 deg F. Basically, the alloy consists of 15 to 22 wt.% molybdenum, a small amount of carbon, and 6 to 8 wt.% chromium, the balance being nickel. Up to 4 wt.% of tungsten, tantalum, vanadium, or niobium may be added to strengthen the alloy.

  11. Structure and properties of stir-cast zinc alloys

    Energy Technology Data Exchange (ETDEWEB)

    LeHuy, H.; Blain J.; Masounave, J.; Bata, G.L. (Industrial Materials Research Institute, Boucherville, P.Q. (Canada))

    Stir casting (or rheocasting) of ZA-27 zinc alloys was investigated experimentally. By vigorously agitating the alloys during cooling, the dendrites that were forming were fragmented giving a unique structure composed of spherical and rosette shaped particles suspended in the remaining liquid. Under high shear rates ({center dot}{gamma} = 300s{sup {minus}1} or more) the slurries with primary particle concentrations as high as 60% displayed viscosities as low as 20 poises and could easily be casted. The effects of processing variables such as shearing and cooling rates and casting temperatures were studied. Their relative importance on the rheological and microstructural behavior of the stir cast alloys are discussed. Results from viscosity measurements on slurries show that non-dendritical ZA-27 alloys obey a power law fluid model. Finally, results from mechanical and compressive studies carried out on solidified slurries are discussed and compared to conventional casted and wrought alloy properties.

  12. Designation and development of biomedical Ti alloys with finer biomechanical compatibility in long-term surgical implants

    Science.gov (United States)

    Yu, Zhen-Tao; Zhang, Ming-Hua; Tian, Yu-Xing; Cheng, Jun; Ma, Xi-Qun; Liu, Han-Yuan; Wang, Chang

    2014-09-01

    Developing the new titanium alloys with excellent biomechanical compatibility has been an important research direction of surgical implants materials. Present paper summarizes the international researches and developments of biomedical titanium alloys. Aiming at increasing the biomechanical compatibility, it also introduces the exploration and improvement of alloy designing, mechanical processing, microstructure and phase transformation, and finally outlines the directions for scientific research on the biomedical titanium alloys in the future.

  13. Hydrogenation properties of Mg-Al alloys

    DEFF Research Database (Denmark)

    Andreasen, Anders

    2008-01-01

    In this paper the properties of Mg-Al alloys in relation to hydrogen storage are reviewed. The main topics of this paper are materials preparation, hydrogen capacity, thermodynamics of hydride formation, and the kinetics of hydride formation and decomposition. Hydrogenation of Mg-Al leads...... to disproportionation with the formation of magnesium hydride and metallic aluminum as the final product. Experimental evidence renders this process reversible. It is observed that the enthalpy of hydride formation of magnesium is lowered upon alloying with Al due to a slightly endothermic disproportionation reaction....... Further, it is found that the kinetics of hydrogenation, as well dehydrogenation, may be significantly improved by alloying compared to pure Mg. The expense of these improvements of the hydrogenation/dehydrogenation properties is a lower gravimetric hydrogen density in the hydrogenated product, (C) 2008...

  14. Microstructure and Service Properties of Copper Alloys

    Directory of Open Access Journals (Sweden)

    Polok-Rubiniec M.

    2016-09-01

    Full Text Available This elaboration shows the effect of combined heat treatment and cold working on the structure and utility properties of alloyed copper. As the test material, alloyed copper CuTi4 was employed. The samples were subjected to treatment according to the following schema: 1st variant – supersaturation and ageing, 2nd variant – supersaturation, cold rolling and ageing. The paper presents the results of microstructure, hardness, and abrasion resistance. The analysis of the wipe profile geometry was realized using a Zeiss LSM 5 Exciter confocal microscope. Cold working of the supersaturated solid solution affects significantly its hardness but the cold plastic deformation causes deterioration of the wear resistance of the finally aged CuTi4 alloy.

  15. Searching for Next Single-Phase High-Entropy Alloy Compositions

    Directory of Open Access Journals (Sweden)

    David E. Alman

    2013-10-01

    Full Text Available There has been considerable technological interest in high-entropy alloys (HEAs since the initial publications on the topic appeared in 2004. However, only several of the alloys investigated are truly single-phase solid solution compositions. These include the FCC alloys CoCrFeNi and CoCrFeMnNi based on 3d transition metals elements and BCC alloys NbMoTaW, NbMoTaVW, and HfNbTaTiZr based on refractory metals. The search for new single-phase HEAs compositions has been hindered by a lack of an effective scientific strategy for alloy design. This report shows that the chemical interactions and atomic diffusivities predicted from ab initio molecular dynamics simulations which are closely related to primary crystallization during solidification can be used to assist in identifying single phase high-entropy solid solution compositions. Further, combining these simulations with phase diagram calculations via the CALPHAD method and inspection of existing phase diagrams is an effective strategy to accelerate the discovery of new single-phase HEAs. This methodology was used to predict new single-phase HEA compositions. These are FCC alloys comprised of CoFeMnNi, CuNiPdPt and CuNiPdPtRh, and HCP alloys of CoOsReRu.

  16. Chronic lymphocytic leukemia: treatment options for patients with refractory disease.

    Science.gov (United States)

    Motta, Marina; Wierda, William G; Ferrajoli, Alessandra

    2009-09-01

    Patients with purine analogue-refractory chronic lymphocytic leukemia (CLL) have short survival and limited treatment options. Defining the best salvage strategies for this population is challenging, because limited data are available from clinical trials, and because studies have enrolled mixed populations (patients with recurrent and refractory disease or patients with refractory disease and Richter transformation). Moreover, patients with refractory CLL have a high incidence of unfavorable molecular and clinical features, such as high-risk genomic profiles, unmutated immunoglobulin heavy-chain genes, expression of zeta-chain-associated protein kinase 70, and bulky lymphadenopathies. These patients are also severely immunosuppressed because of the underlying disease and the treatments received, and experience a high rate of infectious complications that pose an additional difficulty in selecting treatment. Despite these challenges, in parallel with better characterizations of the biologic features of refractory CLL, the number of available treatment modalities for this population has increased. Several chemoimmunotherapy combinations have been developed, and novel agents with a different mechanism of action are being investigated in clinical trials. Furthermore, allogeneic stem cell transplantation with nonmyeloablative conditioning regimens is a therapeutic strategy that is increasingly offered to patients with refractory CLL.

  17. Refractory ceramic fibers activate alveolar macrophage eicosanoid and cytokine release.

    Science.gov (United States)

    Leikauf, G D; Fink, S P; Miller, M L; Lockey, J E; Driscoll, K E

    1995-01-01

    Refractory ceramic fiber has been developed for industrial processes requiring materials with high thermal and mechanical stability. To evaluate the biological activity of this fiber, rat alveolar macrophages were exposed for < or = 24 h to 0-1,000 micrograms/ml of refractory ceramic fiber, crocidolite asbestos, silica (fibrogenic particles), or titanium dioxide (a nonfibrogenic particle), and eicosanoid, tumor necrosis factor-alpha (TNF), and lactate dehydrogenase release were measured. Particle dimensions were determined by electron microscopy. Radioactivity coeluting with leukotriene B4 (LTB4) and immunoreactive LTB4 and TNF release increased after refractory ceramic fiber and were similar in magnitude after asbestos but less than after silica. For example, the total [3H]eicosanoid release increased 3.9-fold after refractory ceramic fiber, 4.6-fold after asbestos, and 8.7-fold after silica. Refractory ceramic fiber and asbestos also have similar particle dimensions (diameter, length, and surface area). Inasmuch as macrophage-derived LTB4 and TNF are potent mediators in inflammatory events, including migration and activation of neutrophils, these findings suggest that refractory ceramic fiber can activate macrophages in vitro to release mediators relevant to in vivo findings of inflammation and fibrotic lung disease in laboratory animals.

  18. Refractory diarrhea: A paraneoplastic syndrome of neuroblastoma.

    Science.gov (United States)

    Han, Wei; Wang, Huan-Min

    2015-07-01

    Neuroblastoma (NB) is the most common extracranial solid tumor in children. Diarrheal NB is quite rare and is not easy to diagnose in the early stage. Six cases of diarrheal NB in our hospital treated from 1996 to 2006 were retrospectively analyzed, including characteristics such as electrolyte imbalance, pathologic features, vasoactive intestinal peptide (VIP) immunohistochemical staining results, treatment, and prognosis. All patients were boys with 3-8 loose or watery stools each day and routine fecal tests were normal. Abdominal tumors were identified by B-ultrasound. Drugs were ineffective. Three patients underwent surgery, and the remaining three patients received surgery and chemotherapy. Diarrhea stopped after treatment in five patients. Two patients died due to intractable hypokalemia. The tumor was located in the adrenal gland in four patients, in the upper retroperitoneum in one patient, and in the presacral area in one patient. Pathologic findings were NB and ganglioneuroblastoma. Five patients were at clinical stage I-II, and one was at stage III. Four patients survived (followed-up for 6 mo to 4 years). Immunohistochemical staining for VIP was positive. Refractory diarrhea is a paraneoplastic syndrome of NB and is rare. Patients aged 1-3 years who present with chronic intractable diarrhea should be followed closely. Intractable diarrhea, hypokalemia, and dysplasia are the initial clinical manifestations. Increased VIP is characteristic of this disease. Potassium supplementation plays a vital role in the treatment procedure, especially preoperatively. The prognosis of diarrheal NB is good following appropriate treatment.

  19. Nonlinear Refractory Plasmonics with Titanium Nitride Nanoantennas.

    Science.gov (United States)

    Gui, Lili; Bagheri, Shahin; Strohfeldt, Nikolai; Hentschel, Mario; Zgrabik, Christine M; Metzger, Bernd; Linnenbank, Heiko; Hu, Evelyn L; Giessen, Harald

    2016-09-14

    Titanium nitride (TiN) is a novel refractory plasmonic material which can sustain high temperatures and exhibits large optical nonlinearities, potentially opening the door for high-power nonlinear plasmonic applications. We fabricate TiN nanoantenna arrays with plasmonic resonances tunable in the range of about 950-1050 nm by changing the antenna length. We present second-harmonic (SH) spectroscopy of TiN nanoantenna arrays, which is analyzed using a nonlinear oscillator model with a wavelength-dependent second-order response from the material itself. Furthermore, characterization of the robustness upon strong laser illumination confirms that the TiN antennas are able to endure laser irradiation with high peak intensity up to 15 GW/cm(2) without changing their optical properties and their physical appearance. They outperform gold antennas by one order of magnitude regarding laser power sustainability. Thus, TiN nanoantennas could serve as promising candidates for high-power/high-temperature applications such as coherent nonlinear converters and local heat sources on the nanoscale.

  20. Iron-refractory iron deficiency anemia.

    Science.gov (United States)

    Yılmaz Keskin, Ebru; Yenicesu, İdil

    2015-03-05

    Iron is essential for life because it is indispensable for several biological reactions, such as oxygen transport, DNA synthesis, and cell proliferation. Over the past few years, our understanding of iron metabolism and its regulation has changed dramatically. New disorders of iron metabolism have emerged, and the role of iron as a cofactor in other disorders has begun to be recognized. The study of genetic conditions such as hemochromatosis and iron-refractory iron deficiency anemia (IRIDA) has provided crucial insights into the molecular mechanisms controlling iron homeostasis. In the future, these advances may be exploited to improve treatment of both genetic and acquired iron disorders. IRIDA is caused by mutations in TMPRSS6, the gene encoding matriptase-2, which downregulates hepcidin expression under conditions of iron deficiency. The typical features of this disorder are hypochromic, microcytic anemia with a very low mean corpuscular volume of erythrocytes, low transferrin saturation, no (or inadequate) response to oral iron, and only a partial response to parenteral iron. In contrast to classic iron deficiency anemia, serum ferritin levels are usually low-normal, and serum or urinary hepcidin levels are inappropriately high for the degree of anemia. Although the number of cases reported thus far in the literature does not exceed 100, this disorder is considered the most common of the "atypical" microcytic anemias. The aim of this review is to share the current knowledge on IRIDA and increase awareness in this field.

  1. Electron microscopy study of refractory ceramic fibers.

    Science.gov (United States)

    MacKinnon, P A; Lentz, T J; Rice, C H; Lockey, J E; Lemasters, G K; Gartside, P S

    2001-10-01

    In epidemiological studies designed to identify potential health risks of exposures to synthetic vitreous fibers, the characterization of airborne fiber dimensions may be essential for assessing mechanisms of fiber toxicity. Toward this end, air sampling was conducted as part of an industry-wide study of workers potentially exposed to airborne fibrous dusts during the manufacture of refractory ceramic fibers (RCF) and RCF products. Analyses of a subset of samples obtained on the sample filter as well as on the conductive sampling cowl were performed using both scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to characterize dimensions of airborne fibers. Comparison was made of bivariate fiber size distributions (length and diameter) from air samples analyzed by SEM and by TEM techniques. Results of the analyses indicate that RCF size distributions include fibers small enough in diameter ( 60 microm) may go undetected by TEM, as evidenced by the proportion of fibers in this category for TEM and SEM analyses (1% and 5%, respectively). Limitations of the microscopic techniques and differences in fiber-sizing rules for each method are believed to have contributed to the variation among fiber-sizing results. It was concluded from these data that further attempts to characterize RCF exposure in manufacturing and related operations should include analysis by TEM and SEM, since the smallest diameter fibers are not resolved with SEM and the fibers of longer length are not sized by TEM.

  2. Iron-Refractory Iron Deficiency Anemia

    Science.gov (United States)

    Yılmaz Keskin, Ebru; Yenicesu, İdil

    2015-01-01

    Iron is essential for life because it is indispensable for several biological reactions, such as oxygen transport, DNA synthesis, and cell proliferation. Over the past few years, our understanding of iron metabolism and its regulation has changed dramatically. New disorders of iron metabolism have emerged, and the role of iron as a cofactor in other disorders has begun to be recognized. The study of genetic conditions such as hemochromatosis and iron-refractory iron deficiency anemia (IRIDA) has provided crucial insights into the molecular mechanisms controlling iron homeostasis. In the future, these advances may be exploited to improve treatment of both genetic and acquired iron disorders. IRIDA is caused by mutations in TMPRSS6, the gene encoding matriptase-2, which downregulates hepcidin expression under conditions of iron deficiency. The typical features of this disorder are hypochromic, microcytic anemia with a very low mean corpuscular volume of erythrocytes, low transferrin saturation, no (or inadequate) response to oral iron, and only a partial response to parenteral iron. In contrast to classic iron deficiency anemia, serum ferritin levels are usually low-normal, and serum or urinary hepcidin levels are inappropriately high for the degree of anemia. Although the number of cases reported thus far in the literature does not exceed 100, this disorder is considered the most common of the “atypical” microcytic anemias. The aim of this review is to share the current knowledge on IRIDA and increase awareness in this field. PMID:25805669

  3. Mobilization of refractory chronic schizophrenics with haloperidol.

    Science.gov (United States)

    Psaras, M; Zissis, N P; Mouzakis, D; Lyketsos, G

    1980-01-01

    Adequate high doses of haloperidol have been administered to 24 chronic, refractory to standard antipsychotic treatment, schizophrenics (16 male, 8 female, mean age 32.9 years) to investigate the possibility of mobilizing and releasing these patients from the hospital. Treatment was started with 20 mg haloperidol and optimal doses were determined for each patient. The median daily optimal dose at the end of the trial was 100mg. All patients were followed up for 16 weeks. Evaluating criteria were the BPRS, the Discharge Readiness Questionnaire, a side-effect rating scale, a CGI scale and the number of patients able to leave the hospital. 3 patients were evaluated as able to leave the hospital. 87.4% of the patients were subjectively evaluated as improved. High doses of haloperidol did not correlate with a higher incidence of unwanted effects. On the contrary antiparkinson treatment was discontinued or decreased in 14 patients. It is concluded that nonresponsive chronic schizophrenics can profit from adequate high doses of haloperidol.

  4. Lenalidomide for relapsed or refractory multiple myeloma

    Directory of Open Access Journals (Sweden)

    S. S. Bessmeltsev1

    2012-01-01

    Full Text Available We report the activity of lenalidomide (revlimide – R, lenalidomide plus dexamethasone (Rd, lenalidomide plus bortezomib plus dexamethasone (RVd in 34 patients with relapsed and refractory myeloma. For patients who received lenalidomide the overall response rate was 70.5 %. 38 % patients achieved very good partial response (VGPR + complete response (CR. Median overall survival (OS was 48 months. Lenalidomide may overcome the poor prognostic impact of various factors, particularly elevated beta (2-microglobulin. Lenalidomide is highly active in elderly patients (> 65 years. Significantly increased OS with a lenalidomide-based induction and lenalidomide maintenance therapy was revealed. The median duration of the overall response without lenalidomide maintenance therapy was 10 months. The median duration of the overall response with lenalidomide maintenance therapy was 20 months (р < 0,05. Median OS with lenalidomide maintenance therapy was not reached. Median OS without lenalidomide maintenance therapy was 36 months (р < 0.05. Side effects were predictable and manageable. The most common adverse events reported were neutropenia (38.3 % and thrombocytopenia (23.7 %. Serious adverse events were rare.

  5. Levetiracetam in children with refractory status epilepticus.

    Science.gov (United States)

    Gallentine, William B; Hunnicutt, Addie S; Husain, Aatif M

    2009-01-01

    The objective of this study was to investigate the utility of levetiracetam (LEV) in children with refractory status epilepticus (RSE). Records of children with RSE who received LEV as adjunctive therapy were reviewed. Over a 7-year period, 11 children had received LEV for RSE. Age ranged from 2 days to 9 years (median = 2.5 months). Prior to administration of LEV, the number of anticonvulsants used to treat RSE ranged from 2 to 7 (median = 3). Starting doses of LEV ranged from 15 to 70 mg/kg (median = 30 mg/kg). LEV was felt to be of benefit in 45% (5/11) of cases, resulting in either resolution of RSE or successful weaning of patients off continuous infusions of other anticonvulsants. In 27% (3/11), response to LEV was unclear as other medications were either added or increased concomitantly with LEV use. The median latency to cessation of RSE following LEV initiation was 1.5 days (range = 1-8 days). All responding patients were on LEV doses >or= 30 mg/kg/day (median 40 mg/kg/day). No significant adverse effects of LEV were reported. LEV may be an effective and safe adjuvant therapy in children with RSE.

  6. Microstructure Modeling of 3rd Generation Disk Alloy

    Science.gov (United States)

    Jou, Herng-Jeng

    2008-01-01

    The objective of this initiative, funded by NASA's Aviation Safety Program, is to model, validate, and predict, with high fidelity, the microstructural evolution of third-generation high-refractory Ni-based disc superalloys during heat treating and service conditions. This initiative is a natural extension of the DARPA-AIM (Accelerated Insertion of Materials) initiative with GE/Pratt-Whitney and with other process simulation tools. Strong collaboration with the NASA Glenn Research Center (GRC) is a key component of this initiative and the focus of this program is on industrially relevant disk alloys and heat treatment processes identified by GRC. Employing QuesTek s Computational Materials Dynamics technology and PrecipiCalc precipitation simulator, physics-based models are being used to achieve high predictive accuracy and precision. Combining these models with experimental data and probabilistic analysis, "virtual alloy design" can be performed. The predicted microstructures can be optimized to promote desirable features and concurrently eliminate nondesirable phases that can limit the reliability and durability of the alloys. The well-calibrated and well-integrated software tools that are being applied under the proposed program will help gas turbine disk alloy manufacturers, processing facilities, and NASA, to efficiently and effectively improve the performance of current and future disk materials.

  7. Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Gurney, Kevin R

    2015-01-12

    This document constitutes the final report under DOE grant DE-FG-08ER64649. The organization of this document is as follows: first, I will review the original scope of the proposed research. Second, I will present the current draft of a paper nearing submission to Nature Climate Change on the initial results of this funded effort. Finally, I will present the last phase of the research under this grant which has supported a Ph.D. student. To that end, I will present the graduate student’s proposed research, a portion of which is completed and reflected in the paper nearing submission. This final work phase will be completed in the next 12 months. This final workphase will likely result in 1-2 additional publications and we consider the results (as exemplified by the current paper) high quality. The continuing results will acknowledge the funding provided by DOE grant DE-FG-08ER64649.

  8. Final Report

    Energy Technology Data Exchange (ETDEWEB)

    DeTar, Carleton [P.I.

    2012-12-10

    This document constitutes the Final Report for award DE-FC02-06ER41446 as required by the Office of Science. It summarizes accomplishments and provides copies of scientific publications with significant contribution from this award.

  9. Aflibercept in exudative age related macular degeneration refractory to ranibizumab.

    Science.gov (United States)

    Ruiz Ramos, J; Pascual-Camps, I; Cuéllar-Monreal, M J; Dolz-Marco, R; Fenoll, M A; Font-Noguera, I; Poveda-Andrés, J L; Gallego-Pinazo, R

    2015-12-01

    The aim of this study is to determine the effectiveness, safety and cost of aflibercept in the treatment of wet age-related macular degeneration (ARMD) refractory to ranibizumab. Retrospective observational study was conducted on patients diagnosed with wet ARMD, and previously treated with ranibizumab. Efficacy variables assessed were changes in visual acuity (BCVA) and anatomical improvements in the most affected eye. Factors associated with improvement of BCVA with aflibercept were also studied. Adverse events related to the aflibercept administration were recorded. Cost analysis data were collected from the hospital perspective, and only taking the direct medical costs into account. Cost-effectiveness analysis was calculated using the aflibercept treatment cost, and effectiveness calculated as BCVA gained. A total of 50 eyes corresponding to 46 patients were included. The median follow-up period was 4.6 months (range: 1.0-6.0). Improvement in visual acuity after the first 2 doses and at the end of the follow-up period was observed in 32.0 and 28.0% of treated eyes, respectively. None of the variables studied was associated with an improvement in the BCVA after treatment. No significant differences were found in the average monthly cost between treatments. Aflibercept is shown to be an effective treatment in a significant number of patients resistant to treatment with ranibizumab, presenting a cost similar to that generated during the final stages of treatment with ranibizumab. Copyright © 2015 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

  10. Ductile transplutonium metal alloys

    Science.gov (United States)

    Conner, William V.

    1983-01-01

    Alloys of Ce with transplutonium metals such as Am, Cm, Bk and Cf have properties making them highly suitable as sources of the transplutonium element, e.g., for use in radiation detector technology or as radiation sources. The alloys are ductile, homogeneous, easy to prepare and have a fairly high density.

  11. Experimental investigation of the behaviour of tungsten and molybdenum alloys at high strain-rate and temperature

    Directory of Open Access Journals (Sweden)

    Scapin Martina

    2015-01-01

    Full Text Available The introduction in recent years of new, extremely energetic particle accelerators such as the Large Hadron Collider (LHC gives impulse to the development and testing of refractory metals and alloys based on molybdenum and tungsten to be used as structural materials. In this perspective, in this work the experimental results of a tests campaign on Inermet®  IT180 and pure Molybdenum (sintered by two different producers are presented. The investigation of the mechanical behaviour was performed in tension varying the strain-rates, the temperatures and both of them. Overall six orders of magnitude in strain-rate (between 10−3 and 103 s−1 were covered, starting from quasi-static up to high dynamic loading conditions. The high strain-rate tests were performed using a direct Hopkinson Bar setup. Both in quasi-static and high strain-rate conditions, the heating of the specimens was obtained with an induction coil system, controlled in feedback loop, based on measurements from thermocouples directly welded on the specimen. The temperature range varied between 25 and 1000°C. The experimental data were, finally, used to extract the parameters of the Zerilli-Armstrong model used to reproduce the mechanical behaviour of the investigated materials.

  12. Autologous Stem Cell Transplant Followed by Donor Stem Cell Transplant in Treating Patients With Relapsed or Refractory Lymphoma

    Science.gov (United States)

    2016-02-23

    Prolymphocytic Leukemia; Recurrent Adult Hodgkin Lymphoma; Recurrent Childhood Hodgkin Lymphoma; Recurrent Childhood Non-Hodgkin Lymphoma; Recurrent Chronic Lymphocytic Leukemia; Recurrent Non-Hodgkin Lymphoma; Recurrent Small Lymphocytic Lymphoma; Refractory Childhood Hodgkin Lymphoma; Refractory Chronic Lymphocytic Leukemia; Refractory Hodgkin Lymphoma; Refractory Non-Hodgkin Lymphoma; Refractory Small Lymphocytic Lymphoma; T-Cell Chronic Lymphocytic Leukemia; T-Cell Prolymphocytic Leukemia

  13. Ultrahigh temperature intermetallic alloys

    Energy Technology Data Exchange (ETDEWEB)

    Brady, M.P.; Zhu, J.H.; Liu, C.T.; Tortorelli, P.F.; Wright, J.L.; Carmichael, C.A.; Walker, L.R. [Oak Ridge National Lab., TN (United States). Metals and Ceramics Div.

    1997-12-01

    A new family of Cr-Cr{sub 2}X based alloys with fabricability, mechanical properties, and oxidation resistance superior to previously developed Cr-Cr{sub 2}Nb and Cr-Cr{sub 2}Zr based alloys has been identified. The new alloys can be arc-melted/cast without cracking, and exhibit excellent room temperature and high-temperature tensile strengths. Preliminary evaluation of oxidation behavior at 1100 C in air indicates that the new Cr-Cr{sub 2}X based alloys form an adherent chromia-based scale. Under similar conditions, Cr-Cr{sub 2}Nb and Cr-Cr{sub 2}Zr based alloys suffer from extensive scale spallation.

  14. The management of refractory coeliac disease

    Science.gov (United States)

    2013-01-01

    A significant proportion of patients with coeliac disease are ‘nonresponsive’ to gluten withdrawal. Most cases of nonresponsive coeliac disease are due to persisting gluten ingestion. Refractory coeliac disease (RCD) is currently defined by persistent symptoms and signs of malabsorption after gluten exclusion for 12 months with ongoing intestinal villous atrophy. Primary (without initial response to diet) and secondary (relapse following response to diet) RCD is recognized. RCD is further classified as type I or type II based on the absence or presence of a population of aberrant intestinal lymphocytes. Quality of dietetic advice and support is fundamental, and lack of objective corroboration of gluten exclusion may result in over-identification of RCD I, particularly in those cases with persisting antibody responses. Over-reliance on lymphocyte clonality similarly may result in over-diagnosis of RCD II which requires careful quantification of aberrant lymphocyte populations. Management of RCD should be undertaken in specialist centres. It requires initial intensive dietary supervision, strict gluten exclusion and subsequent re-evaluation. There is currently insufficient evidence to recommend specific treatments. Steroids are often used in both RCD I and II (albeit with little objective evidence of benefit in RCD II), and azathioprine as steroid-sparing therapy in RCD I. There is growing evidence for the use of cladribine in RCD II with autologous stem cell transplantation in nonresponders, but this requires further multicentre evaluation. There remains considerable controversy regarding the diagnosis, treatment and surveillance of RCD: international consensus in these areas is urgently required to facilitate future therapeutic advances. PMID:23556127

  15. Surgical treatment for medically refractory myasthenic blepharoptosis

    Directory of Open Access Journals (Sweden)

    Shimizu Y

    2014-09-01

    Full Text Available Yusuke Shimizu,1 Shigeaki Suzuki,2 Tomohisa Nagasao,1 Hisao Ogata,1 Masaki Yazawa,1 Norihiro Suzuki,2 Kazuo Kishi1 1Department of Plastic and Reconstructive Surgery, 2Department of Neurology, Keio University School of Medicine, Tokyo, JapanPurpose: Currently, only a few reports have recommended surgery as a suitable treatment for blepharoptosis associated with myasthenia gravis. The present study aims to introduce our surgical criteria, surgical options, outcomes, and precautions for medically refractory myasthenic blepharoptosis. Patients and methods: Eight patients who failed to respond to at least 2 years of medical treatment and who underwent blepharoptosis surgery, from January 2008 to December 2011, were enrolled in this study. Medical records, photographs, and questionnaire results regarding postoperative status were evaluated. Of the eleven procedures performed, four involved frontal suspension, four involved external levator advancement, one involved nonincisional transconjunctival levator advancement, and two involved subbrow blepharoplasty with orbicularis oculi muscle tucking. The margin reflex distance improved postoperatively in seven patients. Results: Seven patients had very minimal scarring, and one had minimal scarring. Five patients showed no eyelid asymmetry, one had subtle asymmetry, and two had obvious asymmetry. Seven patients were very satisfied, and one patient was satisfied with the overall result. Postoperative complications included mild lid lag with incomplete eyelid closure, prolonged scar redness, and worsened heterophoria. No patient experienced postoperative exposure keratitis or recurrent blepharoptosis during the study period. Conclusion: Our results indicate that blepharoptosis surgery is effective for patients with myasthenia gravis, especially those with residual blepharoptosis despite multiple sessions of medical treatments. We recommend that neurologists and surgeons collaborate more systematically and

  16. Probiotics and refractory chronic spontaneous urticaria.

    Science.gov (United States)

    Nettis, E; Di Leo, E; Pastore, A; Distaso, M; Zaza, I; Vacca, M; Macchia, L; Vacca, A

    2016-09-01

    Background. In chronic spontaneous urticaria (CSU) first-line therapy with an antihistamine-based regimen may not achieve satisfactory control in patients. Thus, a continuing need exists for effective and safe treatments for refractory CSU. Aim. To evaluate the clinical efficacy and safety of an intake of a combination of 2 probiotics (Lactobacillus salivarius LS01 and Bifidobacterium breve BR03) in patients with CSU who remain symptomatic despite concomitant H1-antihistamine therapy. Methods. This report analyzes the effects of therapy with two probiotic strains on the clinical progress of 52 unselected patients with difficulty to treat CSU underwent to medical examination in two Italian specialist urticaria Clinics between September 2013 and September 2014. A mixture of Lactobacillus LS01 and Bifidobacterium BR03 were administered in each patient twice daily for 8 weeks. To evaluate patients' improvement with probiotics, urticaria activity score over 7 days (UAS7) was used at baseline and at week 8 in addition to a 5-question urticaria quality of life questionnaire. Results. Fifty-two patients with CSU were included in this study (10 male and 42 female, age range 19-72 years). Mean disease duration was 1.5 years. Fourteen patients discontinued treatment, so evaluable population consisted of 38 patients. Nine of the 38 patients experienced mild clinical improvement during probiotic treatment (23.7%); one patient reported significant clinical improvement (2.6%) and one patient had complete remission of urticaria (2.6%). Twenty-seven patients did not have improvement in symptoms (71.1%). No side effects during the course of therapy were reported. Conclusions. A combination of Lactobacillus salivarius LS01 and Bifidobacterium breve BR03 administered twice daily for 8 weeks might reduce the symptoms scores and improve quality of life scores in a part of patients with CSU who remained symptomatic despite treatment with H1 antihistamine mostly in subjects with allergic

  17. Managing refractory Crohn's disease: challenges and solutions

    Directory of Open Access Journals (Sweden)

    Tanida S

    2015-04-01

    Full Text Available Satoshi Tanida, Keiji Ozeki, Tsutomu Mizoshita, Hironobu Tsukamoto, Takahito Katano, Hiromi Kataoka, Takeshi Kamiya, Takashi Joh Department of Gastroenterology and Metabolism, Nagoya City University Graduate School of Medical Sciences, Aichi Prefecture, Japan Abstract: The goals of treatment for active Crohn's disease (CD are to achieve clinical remission and improve quality of life. Conventional therapeutics for moderate-to-severe CD include 5-aminosalicylic acid, corticosteroids, purine analogs, azathioprine, and 6-mercaptopurine. Patients who fail to respond to conventional therapy are treated with tumor necrosis factor (TNF-α inhibitors such as infliximab and adalimumab, but their efficacy is limited due to primary nonresponse or loss of response. It is suggested that this requires switch to another TNF-α inhibitor, a combination therapy with TNF-α blockade plus azathioprine, or granulocyte and monocyte adsorptive apheresis, and that other therapeutic options having different mechanisms of action, such as blockade of inflammatory cytokines or adhesion molecules, are needed. Natalizumab and vedolizumab are neutralizing antibodies directed against integrin a4 and a4ß7, respectively. Ustekinumab is a neutralizing antibody directed against the receptors for interleukin-12 and interleukin-23. Here, we provide an overview of therapeutic treatments that are effective and currently available for CD patients, as well as some that likely will be available in the near future. We also discuss the advantages of managing patients with refractory CD using a combination of TNF-α inhibitors plus azathioprine or intensive monocyte adsorptive apheresis. Keywords: adalimumab, granulocyte and monocyte adsorptive apheresis, combination therapy, complete remission

  18. Managing refractory cryoglobulinemic vasculitis: challenges and solutions

    Directory of Open Access Journals (Sweden)

    Ostojic P

    2017-05-01

    Full Text Available Predrag Ostojic, Ivan R Jeremic Institute of Rheumatology, School of Medicine, University of Belgrade, Belgrade, Serbia Abstract: Cryoglobulinemia is thought to be a rare condition. It may be an isolated disorder or secondary to a particular disease. According to immunoglobulin composition, cryoglobulinemia is classified into three types. In mixed cryoglobulinemia (types II and III, vascular deposition of cryoglobulin-containing immune complexes and complement may induce a clinical syndrome, characterized by systemic vasculitis and inflammation – cryoglobulinemic vasculitis (CryoVas. Most common clinical manifestations in CryoVas are skin lesions (orthostatic purpura and ulcers, weakness, peripheral neuropathy, Raynaud’s phenomenon, sicca syndrome, membranoproliferative glomerulonephritis, and arthralgia and seldom arthritis. In patients with mixed cryoglobulinemia, prevalence of anti-hepatitis C virus (HCV antibodies and/or HCV RNA, detected by polymerase chain reaction (PCR, is reported to be up to 90%, indicating a significant role of HCV in the development of this condition. The goals of therapy for mixed cryoglobulinemia include immunoglobulin level reduction and antigen elimination. CryoVas not associated with HCV infection should be treated according to treatment recommendations for small-vessel vasculitides. CryoVas associated with chronic HCV infection should be treated with antivirals along with immunosuppressive drugs, with or without plasmapheresis, depending on disease severity and organ involvement. Patients who do not respond to first-line therapy may achieve remission when treatment with rituximab is started as second-line therapy. In HCV-related CryoVas, antiviral therapy should be given along with rituximab in order to achieve complete or partial remission. Moreover, rituximab has proven to be a glucocorticoid-sparing medication. Other potential therapies for refractory CryoVas include mycophenolate mofetil and belimumab

  19. Mg based alloys obtained by mechanical alloying

    Energy Technology Data Exchange (ETDEWEB)

    Ordonez, S. [Univ. de Santiago de Chile (Chile). Fac. de Ingenieria; Garcia, G.; Serafini, D.; San Martin, A.

    1999-07-01

    In the present work, we studied the production of magnesium alloys, of stoichiometry 2Mg + Ni, by mechanical alloying (MA) and the behavior of the alloys under hydrogen in a Sievert`s type apparatus. The elemental powders were milled under argon atmosphere in a Spex 8000 high energy ball mill. The milled materials were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Only minimum amounts of the Mg{sub 2}Ni intermetallic compound was obtained after 22 h of milling time. Most of the material was sticked to the inner surface of the container as well as to the milling balls. Powders milled only for 12 hours transforms to the intermetallic at around 433 K. Effects of the MA on the hydrogen absorption kinetics were also studied. (orig.) 10 refs.

  20. FINAL REPORT

    Energy Technology Data Exchange (ETDEWEB)

    Horn, Mark W; McDaniel, Anthony; Schweighardt, Frank K

    2003-05-23

    In this program the teams at Penn State University (PSU), Sandia National Laboratories (SNL), DCH Technology (DCHT), and Air Products and Chemicals Inc. (APCI), have aggressively pursued engineering solutions to eliminate barriers to solid-state chemiresistor hydrogen sensor technology. The metallurgical effects of alloying palladium with nickel have been shown to prevent phase transitions in the thin films at high H2 overpressures, making the devices more suitable for IOF process conditions. We investigated the use of thin, semi-permeable membranes that protect the catalytic surface from poisoning or other undesirable surface reactions that would otherwise reduce sensitivity or operability in harsh IOF process environments. The results of this project have provided new insight into the effects of metallurgy and protective coatings on device behavior, and open new avenues for research in this field. Commercialization of this sensor technology could be easily achieved, although not yet realized. The benefits to society, once this technology is commercialized, is a dramatic cost and energy savings to the industry, which employs these sensors. In addition, the fundamental understandings gained in this program could have an impact on both cost and safety in the future hydrogen economy utilizing hydrogen fuel cells and hydrogen storage.

  1. Diffusion Couple Alloying of Refractory Metals in Austenitic and Ferritic/Martensitic Steels

    Science.gov (United States)

    2012-03-01

    Top) Photograph of diffusion couple block after hot isostatic pressing. (Bottom) Schematic of diffusion couple cylinders...excess of thermal creep) may raise the susceptibility, initiate, and sustain stress corrosion cracking. Creep also relieves compressive stresses (such as...general corrosion. They have moderate yield strength (~205MPa) which can be cold -worked to further improve it. Stainless steels are relatively

  2. A Computational Tool for the Prediction of Long Term Stability of Refractory Alloys Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA's missions of space exploration require significant power sources both for propulsion and for on-board power. This motivates the development of high temperature...

  3. Accurate Gas Phase Formation Enthalpies of Alloys and Refractories Decomposition Products

    KAUST Repository

    Minenkov, Yury

    2017-01-17

    Accurate gas phase formation enthalpies, ΔHf, of metal oxides and halides are critical for the prediction of the stability of high temperature materials used in the aerospace and nuclear industries. Unfortunately, the experimental ΔHf values of these compounds in the most used databases, such as the NIST-JANAF database, are often reported with large inaccuracy, while some other ΔHf values clearly differ from the value predicted by CCSD(T) methods. To address this point, in this work we systematically predicted the ΔHf values of a series of these compounds having a group 4, 6, or 14 metal. The ΔHf values in question were derived within a composite Feller-Dixon-Peterson (FDP) scheme based protocol that combines the DLPNO-CCSD(T) enthalpy of ad hoc designed reactions and the experimental ΔHf values of few reference complexes. In agreement with other theoretical studies, we predict the ΔHf values for TiOCl2, TiOF2, GeF2, and SnF4 to be significantly different from the values tabulated in NIST-JANAF and other sources, which suggests that the tabulated experimental values are inaccurate. Similarly, the predicted ΔHf values for HfCl2, HfBr2, HfI2, MoOF4, MoCl6, WOF4, WOCl4, GeO2, SnO2, PbBr4, PbI4, and PbO2 also clearly differ from the tabulated experimental values, again suggesting large inaccuracy in the experimental values. In the case when largely different experimental values are available, we point to the value that is in better agreement with our results. We expect the ΔHf values reported in this work to be quite accurate, and thus, they might be used in thermodynamic calculations, because the effects from core correlation, relativistic effects, and basis set incompleteness were included in the DLPNO-CCSD(T) calculations. T1 and T2 values were thoroughly monitored as indicators of the quality of the reference Hartree-Fock orbitals (T1) and potential multireference character of the systems (T2).

  4. Effect of Aluminum on the Microstructure and Properties of Two Refractory High-Entropy Alloys (Postprint)

    Science.gov (United States)

    2014-04-01

    measured with an AccuPyc 1330 V1.03 helium pycnometer. Vickers microhardness was measured on polished cross-section surfaces using a 136 Vickers diamond ...Chang YA, Furrer D, Venkatesh V. J Mater Eng Perf 2005;14(6):717–21. [22] Scheil E. Z Metallkd 1942;34:70. [23] Porter DA, Easterling KE. Phase

  5. Microstructure and mechanical properties of cast Ti-47Al-2Cr-2Nb alloy melted in various crucibles

    Directory of Open Access Journals (Sweden)

    Wang Ligang

    2012-02-01

    Full Text Available The main factors limiting the mass production of TiAl-based components are the high reactivity of TiAl-based alloys with the crucible or mould at high temperature. In this work, various crucibles (e.g. CaO, Y2O3 ceramic crucibles and water-cooled copper crucible were used to fabricate the Ti-47Al-2Cr-2Nb alloy in a vacuum induction furnace. The effects of crucible materials and melting parameters on the microstructure and mechanical properties of the alloy were analyzed by means of microstructure observation, chemical analysis, tensile test and fracture surface observation. The possibilities of melting TiAl alloys in crucibles made of CaO and Y2O3 refractory materials were also discussed.

  6. Commercial off-the-Shelf (COTS) Refractory Material Evaluation

    Science.gov (United States)

    Calle, Luz Marina; Kolody, Mark R.; Curran, Jerome P.; Back, Teddy; Hintze, Paul E.; Parlier, Christopher R.; Sampson, Jeffrey W.; Perusich, Stephen; Bucherl, Cori

    2009-01-01

    Fondu Fyre (FF) is currently the only refractory material qualified for use in the flame trench at KSC's Shuttle Launch Pads 39A and 39B. However, the material is not used as it was qualified and has undergone increasingly frequent and severe degradation due to the launch blasts. This degradation is costly as well as dangerous for launch infrastructure, crew and vehicle. FF is applied at the pad via the gunnite process, where wetted refractory material is sprayed onto a steel grid mounted on a support structure. The water content in this process can be manually adjusted by operators, causing distinct visual and physical discrepancies among repair areas. Since the application process is unlikely to change for new refractory materials, it is important to understand the effects of water content on commercial off-the-shelf (COTS) refractory materials. The purpose of this study was to evaluate the performance of the FF with respect to various water contents as well as heat treatments, to simulate aging and exposure to the blast. Initial results indicated that different water contents and heat treatments result in distinct differences in crushing strength, apparent porosity and bulk density. However, water content became an insignificant factor in both crush strength and porosity when FF was cured to at least 1500 deg. Additionally, inspection of the material's surface microstructure by scanning electron microscopy indicated distinguishable characteristics for different heat treatment levels. Results from this study will help guide future studies on the development and identification of new refractory materials.

  7. Radiosurgery for the management of refractory trigeminal neuralgia

    Directory of Open Access Journals (Sweden)

    Ajay Niranjan

    2016-01-01

    Full Text Available Gamma Knife stereotactic radiosurgery (SRS is a minimally invasive surgical approach for managing medically refractory trigeminal neuralgia (TN. The goal of trigeminal neuralgia SRS is to eliminate or reduce the facial pain in order to improve the quality of life. Over the past 28 years, 1250 patients have undergone gamma knife SRS for TN at our institution. In our retrospective review of 503 patients who underwent SRS for management of refractory TN, 449 patients (89% experienced initial pain relief at a median latency of 1 month. At the one year mark, 73% patients were pain free (with or without medications and 80% had pain control. Repeat radiosurgery was performed for 193 patients (43%. At the one year mark, 26% of these patients were completely pain free and 78% were pain free with or without medications. The role of gamma Knife SRS in the management of medically refractory trigeminal neuralgia has evolved over the past two decades. SRS is a minimally invasive procedure and is associated with 60-90% rate of pain relief in patents with medical refractory trigeminal neuralgia. Early intervention with SRS as the initial surgical procedure for management of refractory trigeminal neuralgia is associated with faster, better, and longer pain relief. As SRS is the least invasive procedure for TN, it is a good treatment option for patients with other high-risk medical conditions. SRS is an attractive alternative especially to those who do not want to accept the greater risk associated with other surgical procedures.

  8. Resistant and Refractory Hypertension: Antihypertensive Treatment Resistance vs Treatment Failure.

    Science.gov (United States)

    Siddiqui, Mohammed; Dudenbostel, Tanja; Calhoun, David A

    2016-05-01

    Resistant or difficult to treat hypertension is defined as high blood pressure that remains uncontrolled with 3 or more different antihypertensive medications, including a diuretic. Recent definitions also include controlled blood pressure with use of 4 or more medications as also being resistant to treatment. Recently, refractory hypertension, an extreme phenotype of antihypertensive treatment failure has been defined as hypertension uncontrolled with use of 5 or more antihypertensive agents, including a long-acting thiazide diuretic and a mineralocorticoid receptor antagonist. Patients with resistant vs refractory hypertension share similar characteristics and comorbidities, including obesity, African American race, female sex, diabetes, coronary heart disease, chronic kidney disease, and obstructive sleep apnea. Patients with refractory vs resistant hypertension tend to be younger and are more likely to have been diagnosed with congestive heart failure. Refractory hypertension might also differ from resistant hypertension in terms of underlying cause. Preliminary evidence suggests that refractory hypertension is more likely to be neurogenic in etiology (ie, heightened sympathetic tone), vs a volume-dependent hypertension that is more characteristic of resistant hypertension in general. Copyright © 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  9. Final Report

    DEFF Research Database (Denmark)

    Heiselberg, Per; Brohus, Henrik; Nielsen, Peter V.

    This final report for the Hybrid Ventilation Centre at Aalborg University describes the activities and research achievement in the project period from August 2001 to August 2006. The report summarises the work performed and the results achieved with reference to articles and reports published...

  10. Influence of time of annealing on anneal hardening effect of a cast CuZn alloy

    OpenAIRE

    Nestorović Svetlana; Ivanić Lj.; Marković Desimir

    2003-01-01

    Investigated cast copper alloy containing 8at%Zn of a solute. For comparison parallel specimens made from cast pure copper. Copper and copper alloy were subjected to cold rolling with different a final reduction of 30,50 and 70%. The cold rolled copper and copper alloy samples were isochronally and isothermally annealed up to recrystallization temperature. After that the values of hardness, strength and electrical conductivity were measured and X-ray analysis was performed. These investigatio...

  11. DIFFERENCES IN INTERICTAL PERFUSION PATTERNS BETWEEN REFRACTORY AND NON-REFRACTORY TEMPORAL LOBE EPILEPSIES EVALUATED WITH FAIR AT 3.0T

    Institute of Scientific and Technical Information of China (English)

    Hui You; Jing-jing Lu; Lian-kun Ren; Xiao-zhen Li; Feng Feng; Chun-ling Meng; Zheng-yu Jin

    2006-01-01

    Objective To investigate the difference in interictal perfusion patterns between refractory and non-refractory temporal lobe epilepsies evaluated with flow-sensitive alternating inversion recovery (FAIR) magnetic resonance (MR) sequence.Methods Nine patients with refractory temporal lobe epilepsy,21 patients with non-refractory temporal lobe epilepsy,and 13 normal volunteers underwent FAIR MR scanning.The relative cerebral blood flow (rCBF) in bilateral hemispheres and mesial temporal lobes were measured.And we also calculated the asymmetry index (AI) values.Results The AI values of bilateral hemispheres in refractory and non-refractory epilepsy patients were both significantly different from those of volunteers (P=0.012 and 0.029,respectively).There was significant difference in AI values of bilateral mesial temporal lobes between non-refractory epilepsy patients and volunteers (P=0.049),while no significant difference between refractory epilepsy patients and volunteers.Conclusions The hypoperfusion pattern of interictal refractory temporal lobe epilepsy patients is different from that of non-refractory patients.Although the hypoperfusion tends to extend out of temporal lobes in all patients,the refractory epilepsy patients have a preference of bilateral mesial temporal hypoperfusion,which may be valuable for evaluating prognosis.

  12. SURFACE MELTING OF ALUMINIUM ALLOYS

    OpenAIRE

    Veit, S.; Albert, D; Mergen, R.

    1987-01-01

    The wear properties of aluminium base alloys are relatively poor. Laser surface melting and alloying has proved successful in many alloy systems as a means of significantly improving the surface properties. The present work describes experiments designed to establish the scope of laser treatment of aluminium alloys. Aluminium does not absorb CO2 laser light as well as other metals which necessitated first a general study of absorption caotings. Aluminium alloys offer fewer opportunities than ...

  13. Analysis of niobium alloys.

    Science.gov (United States)

    Ferraro, T A

    1968-09-01

    An ion-exchange method was applied to the analysis of synthetic mixtures representing various niobium-base alloys. The alloying elements which were separated and determined include vanadium, zirconium, hafnium, titanium, molybdenum, tungsten and tantalum. Mixtures containing zirconium or hafnium, tungsten, tantalum and niobium were separated by means of a single short column. Coupled columns were employed for the resolution of mixtures containing vanadium, zirconium or titanium, molybdenum, tungsten and niobium. The separation procedures and the methods employed for the determination of the alloying elements in their separate fractions are described.

  14. Beta-blockers in cirrhosis and refractory ascites

    DEFF Research Database (Denmark)

    Kimer, Nina; Feineis, Martin; Møller, Søren

    2015-01-01

    OBJECTIVE: It is currently discussed if beta-blockers exert harmful effects and increase mortality in patients with cirrhosis and refractory ascites. In this study, we provide an overview of the available literature in this field in combination with a retrospective analysis of 61 patients...... trials (9 trials on propranolol, 1 case-control study and 4 retrospective analyses) were identified. One trial suggested an increased mortality in patients treated with beta-blockers and refractory ascites. The results of the remaining trials were inconclusive. No increase in mortality among beta-blocker......-treated patients was found in the present retrospective analysis. CONCLUSIONS: Treatment with beta-blockers may increase mortality in patients with cirrhosis and refractory ascites. However, the current evidence is sparse and high-quality studies are warranted to clarify the matter....

  15. Prolonged treatment of refractory status epilepticus in a child.

    Science.gov (United States)

    Sahin, M; Riviello, J J

    2001-02-01

    Barbiturate anesthesia, which is commonly used for refractory status epilepticus, is an effective treatment, but with many significant complications. The relationship between the duration of this extreme therapy and the ultimate outcome of refractory status epilepticus has not been well studied. We report a 7-year-old girl who presented with refractory status epilepticus secondary to presumed encephalitis with a focal lesion on cranial magnetic resonance imaging. She was treated for 70 days with high-dose antiepileptic drugs and recovered with a residual seizure disorder. This case suggests that, if the status epilepticus is due to a reversible cause such as encephalitis, neurologic recovery may occur despite this very prolonged course of extreme therapy.

  16. Neuroimaging in refractory epilepsy. Current practice and evolving trends

    Energy Technology Data Exchange (ETDEWEB)

    Ramli, N. [Department of Biomedical Imaging, University Malaya Research Imaging Centre (Malaysia); Rahmat, K., E-mail: katt_xr2000@yahoo.com [Department of Biomedical Imaging, University Malaya Research Imaging Centre (Malaysia); Lim, K.S.; Tan, C.T. [Neurology Unit, Department of Medicine, University Malaya, Kuala Lumpur (Malaysia)

    2015-09-15

    Highlights: • Neuroimaging is imperative in diagnostic work up and therapeutic assessment of refractory epilepsy. • Identification of epileptogenic zone on EEG, MRI and functional imaging improves the success of surgery. • High performance MRI greatly enhanced metabolic information and elucidate brain functions. • Optimisation of epilepsy protocols in structural and functional MRI are presented in this article. - Abstract: Identification of the epileptogenic zone is of paramount importance in refractory epilepsy as the success of surgical treatment depends on complete resection of the epileptogenic zone. Imaging plays an important role in the locating and defining anatomic epileptogenic abnormalities in patients with medically refractory epilepsy. The aim of this article is to present an overview of the current MRI sequences used in epilepsy imaging with special emphasis of lesion seen in our practices. Optimisation of epilepsy imaging protocols are addressed and current trends in functional MRI sequences including MR spectroscopy, diffusion tensor imaging and fusion MR with PET and SPECT are discussed.

  17. Felbamate in an adult population with severe refractory epilepsy.

    LENUS (Irish Health Repository)

    Kearney, H

    2011-04-05

    Felbamate (FBM) is efficacious in treating patients with refractory epilepsy but was withdrawn due to cases of aplastic anaemia, hepatic failure and five reported deaths. FBM is currently used in specialist centres and is only being used in one Irish centre to date. This papers aim is to review the efficacy and safety experience of FBM in Irish adult patients with refractory epilepsy. A retrospective chart review was done on patients\\' medical records. Patients were subdivided into responders and non responders based on change in seizure frequency and side effects were recorded for all. Of the 13 patients on FBM nine patients responded to FBM, four patients did not. FBM is a safe and efficacious alternative in an Irish adult population with refractory epilepsy. However close monitoring is still required given the potential fatal side effects that are possible with this anticonvulsant.

  18. Thermal Insulation and Strength Characteristics of Refractory Incorporating Natural Silica

    Directory of Open Access Journals (Sweden)

    Namboonruang Weerapol

    2016-01-01

    Full Text Available This work emphasizes on the studying of using silica to develop for the production of refractory materials. Materials are tested at the cured times of 7, 14 and 28 days. Results show that the cold crushing strength, flexural strength and bulk density increase with increasing cured times. On the other hand, the permanent linear change (PLC decreases with increasing cured times. It is also found that adding more silica contents can increase the durability of cracking property due to temperature changing. This study concludes that the silica refractory materials (SRM shows the enough quality to produce as the refractory material, type of the Conventional Cast/Pound (815 °C for the agroindustry using the thermal energy of Thailand.

  19. IMPROVED FURNACE EFFICIENCY THROUGH THE USE OF REFRACTORY MATERIALS

    Energy Technology Data Exchange (ETDEWEB)

    Hemrick, James Gordon [ORNL; Rodrigues-Schroer, Angela [Minteq International, Inc.; Colavito, [Minteq International, Inc.; Smith, Jeffrey D [ORNL

    2011-01-01

    This paper describes efforts performed at Oak Ridge National Laboratory (ORNL), in collaboration with industrial refractory manufacturers, refractory users, and academic institutions, to improve energy efficiency of U.S. industry through increased furnace efficiency brought about by the employment of novel refractory systems and techniques. Work in furnace applications related to aluminum, gasification, and lime are discussed. The energy savings strategies discussed are achieved through reduction of chemical reactions, elimination of mechanical degradation caused by the service environment, reduction of temperature limitations of materials, and elimination of costly installation and repair needs. Key results of several case studies resulting from a US Department of Energy (DOE) funded research program are discussed with emphasis on applicability of these results to high temperature furnace applications.

  20. Depression in patients with refractory temporal lobe epilepsy

    Directory of Open Access Journals (Sweden)

    Eleonora Borges Gonçalves

    2011-10-01

    Full Text Available OBJECTIVE: To evaluate the comorbidity of depressive disorders in patients with refractory temporal lobe epilepsy (TLE. METHOD: We evaluated 25 consecutive patients with refractory TLE (16 women and 9 men, using semi-structured psychiatric interviews, according to the International Classification of Diseases (ICD-10, and the Beck Depression Inventory. RESULTS: Seventeen of 25 patients (68% had depressive disorder: 6 with dysthymia, three with major depressive episodes and 8 with recurrent depressive disorders. Two (8% were diagnosed with mixed anxiety and depression. Only 5 of 17 patients (29.4% were previously diagnosed with depressive disorder and received prior antidepressant treatment. Duration of epilepsy was significantly higher in patients with depressive disorder (p=0.016, but there was no relationship between depression and seizure frequency. CONCLUSION: This study confirmed that depressive disorders are common and underdiagnosed in patients with TLE refractory to AEDs. Patients with longer duration of epilepsy are at higher risk of having depression.

  1. Refractory Characteristics of Aluminum Dross-Kaolin Composite

    Science.gov (United States)

    Adeosun, S. O.; Akpan, E. I.; Dada, M. O.

    2014-11-01

    The suitability of using aluminum dross waste and kaolin to produce refractory bricks is experimentally studied. Thirty brick samples of different blends are produced, dried at 30°C, dried further at 110°C, and fired at 1200°C. The firing temperature point, bulk density, apparent porosity, thermal conductivity, thermal shock, loss on ignition, permeability, shatter index, and shrinkage of the bricks blends are determined. The results show that some blend samples have good refractory characteristics with mixing ratio 4:1:2 (representing weight in grams of aluminum dross, plastic clay, and kaolin, respectively). The evaluations of studied properties reveal the possibility for aluminum dross waste to be used as matrix in refractory bricks.

  2. A new hypothesis of drug refractory epilepsy: neural network hypothesis.

    Science.gov (United States)

    Fang, Min; Xi, Zhi-Qin; Wu, Yuan; Wang, Xue-Feng

    2011-06-01

    Drug refractory is an important clinical problem in epilepsy, affecting a substantial number of patients globally. Mechanisms underlying drug refractory need to be understood to develop rational therapies. Current two prevailing theories on drug refractory epilepsy (DRE) include the target hypothesis and the transporter hypothesis. However, those hypotheses could not be adequate to explain the mechanisms of all the DRE. Thus, we propose another possible mechanism of DRE, which is neural network hypothesis. It is hypothesized that seizure-induced alterations of brain plasticity including axonal sprouting, synaptic reorganization, neurogenesis and gliosis could contribute to the formation of abnormal neural network, which has not only avoided the inhibitory effect of endogenous antiepileptic system but also prevented the traditional antiepileptic drugs from entering their targets, eventually leading to DRE. We will illustrate this hypothesis at molecular and structural level based on our recent studies and other related researches.

  3. Microstructure and interface reaction of investment casting TiAl alloys

    Institute of Scientific and Technical Information of China (English)

    CHEN Yu-yong; XIAO Shu-long; KONG Fan-tao; WANG Xue

    2006-01-01

    In order to research the microstructure of TiAl alloy and TiAl-mould reaction between TiAl and ceramic mould shells prepared with the low cost binder in investment casting, the ceramic mould shells were prepared with low cost binder and refractory materials. Using two kinds of casting methods (gravity casting and centrifugal casting), the titanium aluminum alloys with rare earth element (Ti-47.5Al-2Cr-2Nb-0.3Y and Ti-45Al-5Nb-0.3Y) were cast into the mould shells. The microstructures of investment casting titanium aluminum alloys were observed by optical microscope (OM). The distributions of elements of topping investment on the surfaces of titanium aluminum alloys castings were analyzed by the means of electron probe micro-analysis (EPMA), and the mechanical properties were studied. The results show that the microstructures of two kinds of titanium aluminum alloys are both lamella shape, and lamella is thin. The thickness of reaction and diffusing layer of Ti-47.5Al-2Cr-2Nb-0.3Y alloy is about 80 μm, and that of Ti-45Al-5Nb-0.3Y is less than 30 μm.

  4. Studying the influence of substitutional elements on mechanical behavior of Alloy 718

    Directory of Open Access Journals (Sweden)

    Max Bertrand

    2014-01-01

    Full Text Available In nickel-based superalloys, substitutional solute species have a strong impact on in service mechanical properties as well as on oxidation and corrosion resistances. In alloy 718, recent studies carried out by tensile tests highlighted the fact that refractory solute species are able to interact strongly with mobile dislocations during plastic deformation, generating dynamic strain ageing, and, in wide ranges of tests temperatures and strain rates, Portevin-Le Chatelier effect. The precise nature of the substitutional element responsible for such a dynamic interaction is still subject to debate. We addressed this question by means of mechanical spectroscopy studies of alloy 718 and various related alloys corresponding to monitored changes in the chemical composition. Only a single internal friction relaxation peak has been observed for all the studied alloys. By analyzing the damping behavior of these alloys at different imposed solicitation frequencies by sweeping a large temperatures range, the activation energies of the relaxation process and the type of mechanism involved have been determined. The process is a “Zener relaxation” in the alloys, i.e. a substitutional atoms dipole reorientation under applied stress. The results tend to prove that Niobium is not involved in the relaxation process whereas Molybdenum content seems to play an important role in the relaxation intensity.

  5. Megabit bubble memory process using a new type resin and TaMo alloy-Au conductor

    Science.gov (United States)

    Majima, T.; Hirano, A.; Orihara, S.

    1981-03-01

    A newly developed heat resistant resin, ladder type organosiloxane polymer, is applied to 8 μm period 1 megabit bubble memory devices. Propagation bias margin and reliability are discussed, comparing with the conventional SiO lift-off planar process. TaMo alloy-Au system is also introduced for the conductor. Interdiffusion, electromigration, and corrosion resistance of Au and refractory metals are studied.

  6. Standard Specification for Copper-Aluminum-Silicon-Cobalt Alloy, Copper-Nickel-Silicon-Magnesium Alloy, Copper-Nickel-Silicon Alloy, Copper-Nickel-Aluminum-Magnesium Alloy, and Copper-Nickel-Tin Alloy Sheet and Strip

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2015-01-01

    Standard Specification for Copper-Aluminum-Silicon-Cobalt Alloy, Copper-Nickel-Silicon-Magnesium Alloy, Copper-Nickel-Silicon Alloy, Copper-Nickel-Aluminum-Magnesium Alloy, and Copper-Nickel-Tin Alloy Sheet and Strip

  7. Failure Mechanisms in High Chrome Oxide Gasifier Refractories

    Science.gov (United States)

    Bennett, James P.; Kwong, Kyei-Sing

    2011-04-01

    Gasification is a high-temperature, high-pressure chemical process used to convert a carbon feedstock into CO and H2 (syngas) for use in power generation and the production of chemicals. It is also a leading candidate as a source of hydrogen in a hydrogen economy and is one of several technologies expected to see increased use in advanced fossil fuel power systems in the future. Gasification is being evaluated because of its high efficiency, its ability to capture CO2 for sequestration or reuse in other applications, and its potential for carbon feedstock fuel flexibility. At the heart of the gasification process is a gasifier, a high pressure chemical reaction vessel used to contain the interactions between carbon and water in a shortage of oxygen, producing syngas. The gasifier is lined with high chrome oxide materials to protect the containment vessel. Gasifiers are complex systems, and failure of the refractories used to line them was identified by industry as a limitation to their reliability and availability and to their increased use. NETL researchers have examined spent high-Cr2O3 (over 90 pct Cr2O3) refractories from numerous gasifiers to determine in-service failure mechanisms. This analysis revealed that premature failure of the high chrome oxide refractories was related to ash in the carbon feedstock, which liquefies during gasification and interacts with the refractories, leading to wear by chemical dissolution or spalling (structural and chemical). A discussion of this postmortem wear of spent refractory materials and of thermodynamic modeling used to explain microstructural changes leading to wear are explained in this article. This information will serve the basis to develop improved performance refractory materials.

  8. Refractory strictures despite steroid injection after esophageal endoscopic resection

    Science.gov (United States)

    Hanaoka, Noboru; Ishihara, Ryu; Uedo, Noriya; Takeuchi, Yoji; Higashino, Koji; Akasaka, Tomofumi; Kanesaka, Takashi; Matsuura, Noriko; Yamasaki, Yasushi; Hamada, Kenta; Iishi, Hiroyasu

    2016-01-01

    Background: Although steroid injection prevents stricture after esophageal endoscopic submucosal dissection (ESD), some patients require repeated sessions of endoscopic balloon dilation (EBD). We investigated the risk for refractory stricture despite the administration of steroid injections to prevent stricture in patients undergoing esophageal ESD. Refractory stricture was defined as the requirement for more than three sessions of EBD to resolve the stricture. In addition, the safety of steroid injections was assessed based on the rate of complications. Patients and methods: We analyzed data from 127 consecutive patients who underwent esophageal ESD and had mucosal defects with a circumferential extent greater than three-quarters of the esophagus. To prevent stricture, steroid injection was performed. EBD was performed whenever a patient had symptoms of dysphagia. Results: The percentage of patients with a tumor circumferential extent greater than 75 % was significantly higher in those with refractory stricture than in those without stricture (P = 0.001). Multivariate analysis adjusted for age, sex, history of radiation therapy, tumor location, and tumor diameter showed that a tumor circumferential extent greater than 75 % was an independent risk factor for refractory stricture (adjusted odds ratio [OR] 5.49 [95 %CI 1.91 – 15.84], P = 0.002). Major adverse events occurred in 3 patients (2.4 %): perforation during EBD in 2 patients and delayed perforation after EBD in 1 patient. The patient with delayed perforation underwent esophagectomy because of mediastinitis. Conclusions: A tumor circumferential extent greater than 75 % is an independent risk factor for refractory stricture despite steroid injections. The development of more extensive interventions is warranted to prevent refractory stricture. PMID:27004256

  9. Dependency of calcium alternans on ryanodine receptor refractoriness.

    Directory of Open Access Journals (Sweden)

    Enric Alvarez-Lacalle

    Full Text Available BACKGROUND: Rapid pacing rates induce alternations in the cytosolic calcium concentration caused by fluctuations in calcium released from the sarcoplasmic reticulum (SR. However, the relationship between calcium alternans and refractoriness of the SR calcium release channel (RyR2 remains elusive. METHODOLOGY/PRINCIPAL FINDINGS: To investigate how ryanodine receptor (RyR2 refractoriness modulates calcium handling on a beat-to-beat basis using a numerical rabbit cardiomyocyte model. We used a mathematical rabbit cardiomyocyte model to study the beat-to-beat calcium response as a function of RyR2 activation and inactivation. Bi-dimensional maps were constructed depicting the beat-to-beat response. When alternans was observed, a novel numerical clamping protocol was used to determine whether alternans was caused by oscillations in SR calcium loading or by RyR2 refractoriness. Using this protocol, we identified regions of RyR2 gating parameters where SR calcium loading or RyR2 refractoriness underlie the induction of calcium alternans, and we found that at the onset of alternans both mechanisms contribute. At low inactivation rates of the RyR2, calcium alternans was caused by alternation in SR calcium loading, while at low activation rates it was caused by alternation in the level of available RyR2s. CONCLUSIONS/SIGNIFICANCE: We have mapped cardiomyocyte beat-to-beat responses as a function of RyR2 activation and inactivation, identifying domains where SR calcium load or RyR2 refractoriness underlie the induction of calcium alternans. A corollary of this work is that RyR2 refractoriness due to slow recovery from inactivation can be the cause of calcium alternans even when alternation in SR calcium load is present.

  10. Ketogenic diet treatment for pediatric super-refractory status epilepticus.

    Science.gov (United States)

    Appavu, Brian; Vanatta, Lisa; Condie, John; Kerrigan, John F; Jarrar, Randa

    2016-10-01

    We aimed to study whether ketogenic diet (KD) therapy leads to resolution of super-refractory status epilepticus in pediatric patients without significant harm. A retrospective review was performed at Phoenix Children's Hospital on patients with super-refractory status epilepticus undergoing ketogenic diet therapy from 2011 to 2015. Ten children with super-refractory status epilepticus, ages 2-16 years, were identified. 4/10 patients had immune mediated encephalitis, including Rasmussen encephalitis, anti-N-methyl-d-aspartate receptor encephalitis, and post-infectious mycoplasma encephalitis. Other etiologies included Lennox Gastaut Syndrome, non-ketotic hyperglycinemia, PCDH19 and GABRG2 genetic epilepsy, New Onset Refractory Status Epilepticus, and Febrile Infection-Related Epilepsy Syndrome. 4/10 patients' EEG features suggested focal with status epilepticus, and 6/10 suggested generalized with status epilepticus. Median hospital length was 61days and median ICU length was 27days. The median number of antiepileptic medications prior to diet initiation was 3.0 drugs, and the median after ketogenic diet treatment was 3.5 drugs. Median duration of status epilepticus prior to KD was 18days. 9/10 patients had resolution of super-refractory status epilepticus in a median of 7days after diet initiation. 8/9 patients were weaned off anesthesia within 15days of diet initiation, and within 1day of achieving ketonuria. 1/10 patients experienced side effects on the diet requiring supplementation. Most patients achieved resolution of status epilepticus on KD therapy, suggesting it could be an effective therapy that can be utilized early in the treatment of children with super refractory status epilepticus. Copyright © 2016. Published by Elsevier Ltd.

  11. Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Stinis, Panos [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-08-07

    This is the final report for the work conducted at the University of Minnesota (during the period 12/01/12-09/18/14) by PI Panos Stinis as part of the "Collaboratory on Mathematics for Mesoscopic Modeling of Materials" (CM4). CM4 is a multi-institution DOE-funded project whose aim is to conduct basic and applied research in the emerging field of mesoscopic modeling of materials.

  12. Nickel-Titanium Alloys: Corrosion "Proof" Alloys for Space Bearing, Components and Mechanism Applications

    Science.gov (United States)

    DellaCorte, Christopher

    2010-01-01

    An intermetallic nickel-titanium alloy, 60NiTi (60 wt% Ni, 40 wt% Ti), is shown to be a promising candidate tribological material for space mechanisms. 60NiTi offers a broad combination of physical properties that make it unique among bearing materials. 60NiTi is hard, electrically conductive, highly corrosion resistant, readily machined prior to final heat treatment, and is non-magnetic. Despite its high Ti content, 60NiTi is non-galling even under dry sliding. No other bearing alloy, metallic or ceramic, encompasses all of these attributes. Since 60NiTi contains such a high proportion of Ti and possesses many metallic properties, it was expected to exhibit poor tribological performance typical of Ti alloys, namely galling type behavior and rapid lubricant degradation. In this poster-paper, the oil-lubricated behavior of 60NiTi is presented.

  13. Research progress of gene target therapy for refractory epilepsy

    Directory of Open Access Journals (Sweden)

    Xing-hua TANG

    2014-12-01

    Full Text Available Nowadays, the strategies of gene therapy for the treatment of refractory epilepsy (RE mainly include modulating neurotransmitter systems, neuropeptide Y (NPY and neurotrophic factors. Among them, the hot target spots include γ-aminobutyric acid (GABA and its receptor, N-methyl-D-aspartate (NMDA and its receptor, galanin, NPY and neurotrophic factors. This paper reviews the chief research results, and advantages and disadvantages of studies, and provides evidence for the treatment of refractory epilepsy. doi: 10.3969/j.issn.1672-6731.2014.12.004

  14. Refractory carcinoid syndrome: a review of treatment options

    Science.gov (United States)

    Riechelmann, Rachel P.; Pereira, Allan A.; Rego, Juliana F. M.; Costa, Frederico P.

    2016-01-01

    Carcinoid syndrome (CSy) is a constellation of symptoms that may commonly present in patients with well differentiated neuroendocrine tumors (NETs), with somatostatin analogs (SSAs) being the first-line option for symptom management. However, symptomatic progression eventually occurs and in this scenario of a refractory CSy; several treatment options have been studied such as dose escalation of SSA, interferon and liver-directed therapies. Nevertheless, recent phase III trials have contributed to the understanding and management of this condition. We performed a comprehensive review of interventional studies examining refractory CSy to provide the evidence for current treatment options and propose a treatment sequence. PMID:28203303

  15. EVALUATION OF THE REFRACTORY CHARACTERISTICS OF DUKKU CLAY DEPOSIT

    OpenAIRE

    A.M. Yami; M. A. B. Hassan; Umaru, S.

    2007-01-01

    Dukku clay was investigated to determine its refractory characteristics. The result shows that it has a bulk modulus of 9.27g/cm2, porosity of 27.84%, linear shrinkage of 1.27% and cold crushing strength of 80.20kg/cm3.A thermal shock resistance of 25 cycles was obtained with specific gravity of 2.69g and refractoriness of 1300oC.The sample was also analyzed to determine its chemical composition by atomic absorption spectra photometry method (AAS969). The result of the chemical analysis shows...

  16. The Key Technique of Manufacture of Dense Chromium Sesquioxide Refractories

    Institute of Scientific and Technical Information of China (English)

    LIMaoqiang; ZHANGShuying; 等

    1998-01-01

    Dense chromium sesquioxide refractories have widely been used in the kilns for making alkai-free and anti-alkali glass fibers due to their excellent re-sistance to molten glasses.Densifications of chromium sesquioxide during sintering can be blocked by evaporation of chromium trioxide derived from oxidation at high temperature,In this paper the mech-anism of sintering chromium oxide and the process-ing technique for making dense chromium sesquiox-ide refractories are discussed .A process in laboratory scale for making dense chromium sesquioxide bricks is demonstrated.

  17. Uterine artery embolisation for management of refractory postpartal haemmorhage.

    Science.gov (United States)

    Urundady, Vishalakshi; Shetty, Vrinda

    2012-12-01

    Management of Postpartal Haemorrhage (PPH) refractory to medical management continues to be a formidable condition, further compounded by unstable haemodynamic condition and associated coagulopathy, usually associated with this condition. Though surgical exploration is the usual therapeutic option for such patients, selective pelvic arterial embolisation is gaining the popularity in view of its safety and efficacy profile. Uterine preservation further adds to its advantages.We present our experience of managing 5 such patients with Uterine Artery Embolisation (UAE). The current status of UAE as therapeutic modality for management of refractory PPH is discussed.

  18. The Utility of Cannabidiol in the Treatment of Refractory Epilepsy.

    Science.gov (United States)

    Reddy, D S

    2017-02-01

    Cannabis-derived cannabinoids such as cannabidiol (CBD) have anticonvulsant properties. Recently, there has been an emerging interest in the use of CBD-enriched products for treatment of drug-resistant epilepsy. Some pilot trials of CBD have proved beneficial for refractory epilepsy, but its efficacy is yet to be confirmed by standard placebo-controlled trials. However, the mechanisms underlying the seizure protection efficacy claims of CBD remain unclear. This review briefly describes the clinical utility of CBD in the treatment of refractory epilepsy. © 2016 American Society for Clinical Pharmacology and Therapeutics.

  19. The Future of the Refractory Industry, with a Chinese Perspective

    Institute of Scientific and Technical Information of China (English)

    Michel Rigaud; ZHOU Ningsheng; YE Fangbao

    2005-01-01

    Globalization is a reality resulting in many changes in the refractory industry. In this paper some of the threats and opportunities, which are influencing the future prosperity of the refractory industry on a worldwide basis, are being evoked. Some key technical and management issues are underlined, in terms of adjusting the productivity-quality-cost to the customers requirements; producing unshapes versus shapes; innovations supported by research; international profile for the import-export game; training and education. Consequences for China, who does play a dominant role due to the size of its internal market (customers demand) and the magnitude of its production capability (including raw materials availability) , are being drawn.

  20. Refractory pancytopenia and megaloblastic anemia due to falciparum malaria.

    Science.gov (United States)

    Aggarwal, Varun; Maheshwari, Anu; Rath, Bimbadhar; Kumar, Praveen; Basu, Srikanta

    2011-08-01

    Anemia is a common complication in malarial infection. Direct destruction and ineffective erythropoesis does not adequately explain the cause of anemia in malaria. We present a case with refractory megaloblastic anemia with asymptomatic falciparum malaria. We hypothesize that promoter variants in the inducible nitric oxide synthase gene might be the cause of severe refractory megaloblastic anemia and pancytopenia in our patient. Malaria should always be kept in mind as a cause of anemia especially in endemic areas even if the child is asymptomatic or there is no demonstrable parasite on routine smear examination.

  1. Emissivity Results on High Temperature Coatings for Refractory Composite Materials

    Science.gov (United States)

    Ohlhorst, Craig W.; Vaughn, Wallace L.; Daryabeigi, Kamran; Lewis, Ronald K.; Rodriguez, Alvaro C.; Milhoan, James D.; Koenig, John R.

    2007-01-01

    The directional emissivity of various refractory composite materials considered for application for reentry and hypersonic vehicles was investigated. The directional emissivity was measured at elevated temperatures of up to 3400 F using a directional spectral radiometric technique during arc-jet test runs. A laboratory-based relative total radiance method was also used to measure total normal emissivity of some of the refractory composite materials. The data from the two techniques are compared. The paper will also compare the historical database of Reinforced Carbon-Carbon emissivity measurements with emissivity values generated recently on the material using the two techniques described in the paper.

  2. Improved Refractories for Slagging Gasifiers in IGCC Power Systems

    Energy Technology Data Exchange (ETDEWEB)

    Dogan, Cynthia P.; Kwong, Kyei-Sing; Bennett, James P.; Chinn, Richard E.

    2003-04-24

    The gasification of coal and other carbon-containing fuels provides the opportunity to produce energy more efficiently, and with significantly less environmental impact, than more-conventional combustion-based processes. In addition, the synthesis gas that is the product of the gasification process offers the option of ''polygeneration,'' i.e., the production of alternative products instead of power should it be economically favorable to do so. Because of these advantages, gasification is viewed as one of the key processes in the U.S. Department of Energy's Vision 21 power system. However, issues with both the reliability and the economics of gasifier operation will have to be resolved before gasification will be widely adopted by the power industry. Central to both enhanced reliability and economics is the development of materials with longer service lives in gasifier systems that can provide extended periods of continuous, trouble-free gasifier operation. The focus of the Advanced Refractories for Gasification project at the Albany Research Center is to develop improved refractory materials capable of withstanding the harsh, high-temperature environment created by the gasification reaction, and includes both the refractory lining that protects and insulates the slagging gasifier, as well as the thermocouple assemblies that are utilized to monitor gasifier operating temperatures. Current generation refractory liners in slagging gasifiers are typically replaced every four to 18 months, at costs ranging up to $2,000,000, depending upon the size of the gasification vessel. Compounding materials and installation costs are the lost-opportunity costs for the time that the gasifier is off-line for the refractory exchange. Current generation thermocouple devices rarely survive the gasifier start-up process, leaving the operator with no real means of temperature measurement during routine operation. Reliable, efficient, and economical gasifier

  3. Refractory experience in circulating fluidized bed combustors, Task 7

    Energy Technology Data Exchange (ETDEWEB)

    Vincent, R.Q.

    1989-11-01

    This report describes the results of an investigation into the status of the design and selection of refractory materials for coal-fueled circulating fluidized-bed combustors. The survey concentrated on operating units in the United States manufactured by six different boiler vendors: Babcock and Wilcox, Combustion Engineering, Foster Wheeler, Keeler Dorr-Oliver, Pyropower, and Riley Stoker. Information was obtained from the boiler vendors, refractory suppliers and installers, and the owners/operators of over forty units. This work is in support of DOE's Clean Coal Technology program, which includes circulating fluidized-bed technology as one of the selected concepts being evaluated.

  4. Efficacy and Safety of Rituximab in Children with Refractory Nephrotic Syndrome; A Multicenter Clinical Trial

    Directory of Open Access Journals (Sweden)

    Yo Han Ahn

    2014-06-01

    Conclusions: In this interim analysis of clinical trial to evaluate the efficacy and safety of RTX in children with refractory NS, RTX treatment for refractory NS was safe and effective, especially in patients with DNS.

  5. Nivolumab and Dasatinib in Treating Patients With Relapsed or Refractory Philadelphia Chromosome Positive Acute Lymphoblastic Leukemia

    Science.gov (United States)

    2016-08-25

    B Acute Lymphoblastic Leukemia With t(9;22)(q34;q11.2); BCR-ABL1; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Childhood Acute Lymphoblastic Leukemia; Refractory Adult Acute Lymphoblastic Leukemia; Refractory Childhood Acute Lymphoblastic Leukemia

  6. Reactions Between MgO-C Refractory, Molten Slag and Metal

    National Research Council Canada - National Science Library

    Li, Zushu; Mukai, Kusuhiro; Tao, Zainan

    2000-01-01

    The behavior of MgO-C refractory-slag-metal system, which is caused by the reactions such as the dissolution of MgO and graphite in the refractory into slag and metal respectively and the generation...

  7. Treatment Options for Primary Refractory/Recurrent Hodgkin Lymphoma in Children and Adolescents

    Science.gov (United States)

    ... Primary Refractory/Recurrent Hodgkin Lymphoma in Children and Adolescents Primary refractory Hodgkin lymphoma is lymphoma that continues ... treated with an adult treatment regimen . Children and adolescents may have treatment-related side effects that appear ...

  8. Alloy Selection System

    Energy Technology Data Exchange (ETDEWEB)

    None

    2001-02-01

    Software will Predict Corrosion Rates to Improve Productivity in the Chemical Industry. Many aspects of equipment design and operation are influenced by the choice of the alloys used to fabricate process equipment.

  9. Strength of Hard Alloys,

    Science.gov (United States)

    Partial replacement of titanium carbide by tantalum carbide in three-phase WC-TiC-Co alloys tends to have a favorable effect on mechanical properties such as fatigue strength under bending and impact durability.

  10. Seizure control and developmental trajectories after hemispherotomy for refractory epilepsy in childhood and adolescence.

    Science.gov (United States)

    Ramantani, Georgia; Kadish, Navah Ester; Brandt, Armin; Strobl, Karl; Stathi, Angeliki; Wiegand, Gert; Schubert-Bast, Susanne; Mayer, Hans; Wagner, Kathrin; Korinthenberg, Rudolf; Stephani, Ulrich; van Velthoven, Vera; Zentner, Josef; Schulze-Bonhage, Andreas; Bast, Thomas

    2013-06-01

    To evaluate the seizure control and developmental outcomes after hemispherotomy for refractory epilepsy in childhood and to identify their predictive factors. We retrospectively studied the clinical courses and outcomes of 52 children with refractory epilepsy who underwent hemispherotomy in the Epilepsy Center Freiburg between 2002 and 2011. Mean age at epilepsy onset was 1.8 years (range 0-8 years) and mean age at surgery was 6.7 years (range 6 months-18 years). The underlying etiology was congenital in 22 (42%) children, acquired in 24 (46%), and progressive in 6 (12%). At final follow-up of 1-9.8 years (mean 3.3), 43 children (83%) were seizure-free. Seizure outcome was not correlated to etiology, with the exception of hemimegalencephaly that was linked to poor seizure control. Presurgical development was impaired in all but one child. Postsurgical development highly correlated with presurgical development. Patients with acquired or progressive etiology, later epilepsy onset, and subsequent later surgery exhibited higher presurgical developmental status that substantially determined postoperative developmental outcome. Improved postsurgical development was determined by acquired etiology and seizure freedom off antiepileptic drugs. In our study, most of the selected children and adolescents achieved seizure freedom, including those with congenital etiology. Developmental outcomes, however, were superior in patients with acquired etiology and older age at surgery, underscoring that it is never too late to reap the benefits of this procedure in terms of both epilepsy and development. Wiley Periodicals, Inc. © 2013 International League Against Epilepsy.

  11. First Everlasting Alloy

    Institute of Scientific and Technical Information of China (English)

    杨仲言

    1994-01-01

    There′s new alloy that apparently just won′t give up. When a pin was scraped along it the equivalent of one million times, the alloy-made of zirconium, palladium, and ruthenium—displayed no net loss of surface material. When astonished researchers at the National Institute of Standards and Technology(NIST) persevered with a five-million-cycle wear test, they got the same result.

  12. Machining of titanium alloys

    CERN Document Server

    2014-01-01

    This book presents a collection of examples illustrating the resent research advances in the machining of titanium alloys. These materials have excellent strength and fracture toughness as well as low density and good corrosion resistance; however, machinability is still poor due to their low thermal conductivity and high chemical reactivity with cutting tool materials. This book presents solutions to enhance machinability in titanium-based alloys and serves as a useful reference to professionals and researchers in aerospace, automotive and biomedical fields.

  13. Relapsed/Refractory acute myeloid leukemia patients | EU Clinical Trials Register [EU Clinical Trials Register

    Lifescience Database Archive (English)

    Full Text Available Treatment of relapsed/refractory leukemia with intravenous administration of Dacarbazine Trattamento della leucemia...tment of relapsed/refractory leukemia with intravenous administration of Dacarbazine Trattamento della leucemia...on(s) being investigated Relapsed/Refractory acute myeloid leukemia patients Pazienti affetti da leucemia... language Relapsed/Refractory acute myeloid leukemia patients Pazienti affetti da leucemia acuta mieloide re...arbazina nei pazienti affetti da leucemia acuta mieloide recidivata/refrattaria i cui blasti esprimono bassi

  14. Abstracts from Naihuo Cailiao(Refractories)——A Chinese-Language Bimonthly

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    @@ Volume 43,Number 6,2009 Dissolution behaviors of refractory fiber powders in simulated lung fluid.Wang Xitang,Liu Hao,Zhang Baoguo,et al.(401-404).-Bio-soluble refractory fi-ber,Simulated lung fluid,Dissolution behavior--The dissolution behaviors in Gamble solution (simulated lung fluid)of bio-soluble refractory fiber and alumino-silicate refractory fiber were analyzed and compared using ICP-AES,FTIR,and FESEM.

  15. Erosion Effect of Molten Steel on Carbon Containing Refractories for Continuous Casting

    Institute of Scientific and Technical Information of China (English)

    LI Hongxia; YANG Bin; LIU Guoqi; CHENG Hepeng

    2007-01-01

    The erosion resistance of carbon containing refractories for continuous casting to molten steel was investigated by means of simulative erosion test and examining used refractories.Decolonization and reaction between molten steel and decolonization layer are main erosion process of carbon containing refractories by1 molten steel.The reactions between molten steel and oxide in refractories determine the thickness of decarbonization layer A dense layer formation on the working surface contacting with molten steel during casting will suppress decarbonization and erosion process.

  16. Iron-Refractory Iron Deficiency Anemia

    Directory of Open Access Journals (Sweden)

    Ebru Yılmaz Keskin

    2015-03-01

    Full Text Available Demir, oksijenin taşınması, DNA sentezi ve hücre çoğalması gibi çeşitli biyolojik reaksiyonlar için vazgeçilmez olduğundan, yaşam için zorunludur. Demir metabolizması ve bu elementin düzenlenmesiyle ilgili bilgilerimiz, son yıllarda belirgin şekilde değişmiştir. Demir metabolizması ile ilgili yeni bozukluklar tanımlanmış ve demirin başka bozuklukların kofaktörü olduğu anlaşılmaya başlamıştır. Hemokromatozis ve demir tedavisine dirençli demir eksikliği anemisi (IRIDA; “iron-refractory iron deficiency anemia” gibi genetik durumlar üzerinde yapılan çalışmalar, vücuttaki demir dengesini kontrol eden moleküler mekanizmalar ile ilgili önemli ipuçları sunmuştur. Bu ilerlemeler, gelecekte, hem genetik hem de kazanılmış demir bozukluklarının daha etkili şekilde tedavi edilmesi amacıyla kullanılabilir. IRIDA, demir eksikliği ile giden durumlarda, hepsidin üretimini baskılayan matriptaz-2’yi kodlayan TMPRSS6 genindeki mutasyonlardan kaynaklanmaktadır. Hastalığın tipik özellikleri, hipokrom, mikrositer anemi, çok düşük ortalama eritrosit hacmi, oral demir tedavisine yanıtsızlık (veya yetersiz yanıt ve parenteral demire kısmi yanıttır. Klasik demir eksikliği anemisinin aksine, serum ferritin değeri genellikle hafif düşük ya da normal aralıkta; serum ve idrar hepsidin değerleri ise, aneminin derecesi ile orantısız şekilde yüksek bulunur. Şimdiye kadar literatürde bildirilmiş olguların sayısı 100’ü geçmediği halde, IRIDA’nın, “atipik” mikrositik anemilerin en sık nedeni olduğu düşünülmektedir. Bu derlemenin amacı, IRIDA hakkındaki güncel bilgileri araştırıcılar ile paylaşmak ve bu alandaki farkındalıklarını arttırmaktır.

  17. Cometary Refractory Grains: Interstellar and Nebular Sources

    Science.gov (United States)

    Wooden, D. H.

    2008-07-01

    with asteroids, the Stardust Fe-bearing and Fe-rich crystalline silicates suggests partial aqueous alteration in comet nuclei. However, aqueous alteration transforms Fe-rich olivine to phyllosilicates before Mg-rich olivine, and Stardust has Mg-rich and Fe-rich olivine and no phyllosilicates. Hence, we look to a nebular source for the moderately Fe-rich to nearly pure-Fe crystalline silicates. Primitive matrices have Mg-Fe silicates but no phyllosilicates, supporting the idea that Mg-Fe silicates but not phyllosilicates are products of water-rich shocks. Chondrule-formation is a late stage process in our protoplanetary disk. Stardust samples show comet 81P/Wild 2 formed at least as late to incorporate a few chondrules, requiring radial transport of chondrules out to perhaps >20 AU. By similar radial transport mechanisms, collisional fragments of aqueously altered asteroids, in particular achondrites that formed earlier than chondrules, might reach the comet-forming zones. However, Stardust samples do not have phyllosilicates and chondrules are rare. Hence, the nebular refractory grains in comet 81P/Wild 2, as well as other comets, appear to be pre-accretionary with respect to asteroid parent bodies. By discussing nebular pathways for the formation of Fe-rich crystalline silicates, and also phyllosilicates and carbonates, we put forth the view that comets contain both the interstellar ingredients for and the products of nebular transmutation.

  18. Final Report

    Energy Technology Data Exchange (ETDEWEB)

    R Paul Drake

    2004-01-12

    OAK-B135 This is the final report from the project Hydrodynamics by High-Energy-Density Plasma Flow and Hydrodynamics and Radiation Hydrodynamics with Astrophysical Applications. This project supported a group at the University of Michigan in the invention, design, performance, and analysis of experiments using high-energy-density research facilities. The experiments explored compressible nonlinear hydrodynamics, in particular at decelerating interfaces, and the radiation hydrodynamics of strong shock waves. It has application to supernovae, astrophysical jets, shock-cloud interactions, and radiative shock waves.

  19. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Jarillo-Herrero, Pablo [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

    2017-02-07

    This is the final report of our research program on electronic transport experiments on Topological Insulator (TI) devices, funded by the DOE Office of Basic Energy Sciences. TIbased electronic devices are attractive as platforms for spintronic applications, and for detection of emergent properties such as Majorana excitations , electron-hole condensates , and the topological magneto-electric effect . Most theoretical proposals envision geometries consisting of a planar TI device integrated with materials of distinctly different physical phases (such as ferromagnets and superconductors). Experimental realization of physics tied to the surface states is a challenge due to the ubiquitous presence of bulk carriers in most TI compounds as well as degradation during device fabrication.

  20. Cranialization of the frontal sinus-the final remedy for refractory chronic frontal sinusitis

    NARCIS (Netherlands)

    van Dijk, J. Marc C.; Wagemakers, Michiel; Korsten-Meijer, Astrid G. W.; Buiter, C. T. Kees; van der Laan, Bernard F. A. M.; Mooij, Jan Jakob A.

    2012-01-01

    Object. Chronic sinusitis can be a debilitating disease with significant impact on quality of life. Frontal sinusitis has a relatively low prevalence, but complications can be severe due to its anatomical location. After failure of conservative measures, typically endoscopic procedures are performed