Alkali metal-refractory metal biphase electrode for AMTEC

NASA Technical Reports Server (NTRS)

Williams, Roger M. (Inventor); Bankston, Clyde P. (Inventor); Cole, Terry (Inventor); Khanna, Satish K. (Inventor); Jeffries-Nakamura, Barbara (Inventor); Wheeler, Bob L. (Inventor)

1989-01-01

An electrode having increased output with slower degradation is formed of a film applied to a beta-alumina solid electrolyte (BASE). The film comprises a refractory first metal M.sup.1 such as a platinum group metal, suitably platinum or rhodium, capable of forming a liquid or a strong surface adsorption phase with sodium at the operating temperature of an alkali metal thermoelectric converter (AMTEC) and a second refractory metal insoluble in sodium or the NaM.sup.1 liquid phase such as a Group IVB, VB or VIB metal, suitably tungsten, molybdenum, tantalum or niobium. The liquid phase or surface film provides fast transport through the electrode while the insoluble refractory metal provides a structural matrix for the electrode during operation. A trilayer structure that is stable and not subject to deadhesion comprises a first, thin layer of tungsten, an intermediate co-deposited layer of tungsten-platinum and a thin surface layer of platinum.

High Temperature Oxidation-Resistant Thruster Research

DTIC Science & Technology

1990-02-01

substrates: Refractory metals, ! Ceramics, Composites and I Carbon - carbon . Rhenium and hafnium carbide were selected based on their properties I and... carbon . Rhenium was selected as the primary refractory metal candidate because of its high melting point, no ductile-to- brittle transition in the...of rhenium (Re) with those of other refractory metals. Rhenium has the second highest melting point of the elements, 3013 C, second only to tungsten

Refractory thermal insulation for smooth metal surfaces

NASA Technical Reports Server (NTRS)

1964-01-01

To protect rocket metal surfaces from engine exhaust heat, a refractory thermal insulation mixture, which adheres to smooth metals, has been developed. Insulation protection over a wide temperature range can be controlled by thickness of the applied mixture.

Progress in bioleaching: part B: applications of microbial processes by the minerals industries.

PubMed

Brierley, Corale L; Brierley, James A

2013-09-01

This review presents developments and applications in bioleaching and mineral biooxidation since publication of a previous mini review in 2003 (Olson et al. Appl Microbiol Biotechnol 63:249-257, 2003). There have been discoveries of newly identified acidophilic microorganisms that have unique characteristics for effective bioleaching of sulfidic ores and concentrates. Progress has been made in understanding and developing bioleaching of copper from primary copper sulfide minerals, chalcopyrite, covellite, and enargite. These developments point to low oxidation-reduction potential in concert with thermophilic bacteria and archaea as a potential key to the leaching of these minerals. On the commercial front, heap bioleaching of nickel has been commissioned, and the mineral biooxidation pretreatment of sulfidic-refractory gold concentrates is increasingly used on a global scale to enhance precious metal recovery. New and larger stirred-tank reactors have been constructed since the 2003 review article. One biooxidation-heap process for pretreatment of sulfidic-refractory gold ores was also commercialized. A novel reductive approach to bioleaching nickel laterite minerals has been proposed.

Chronopotentiometry of refractory metals, actinides and oxyanions in molten salts: A review

NASA Technical Reports Server (NTRS)

Bansal, Narottam P.

1992-01-01

The applications of chronopotentiometry to the study of electrochemical behavior of three technologically important areas of refractory metals, actinides, and oxyanions in molten salts are critically reviewed. Chronopotentiometry is a very versatile diagnostic tool to understand the reaction mechanism of the electrode processes for the electrochemical reduction/oxidation of these electroactive species in molten salt solutions. Well adherent, compact, and uniformly thick coatings of refractory metals may be electrodeposited from their solutions in molten salts.

Method of nitriding refractory metal articles

DOEpatents

Tiegs, Terry N.; Holcombe, Cressie E.; Dykes, Norman L.; Omatete, Ogbemi O.; Young, Albert C.

1994-01-01

A method of nitriding a refractory-nitride forming metal or metalloid articles and composite articles. A consolidated metal or metalloid article or composite is placed inside a microwave oven and nitrogen containing gas is introduced into the microwave oven. The metal or metalloid article or composite is heated to a temperature sufficient to react the metal or metalloid with the nitrogen by applying a microwave energy within the microwave oven. The metal or metalloid article or composite is maintained at that temperature for a period of time sufficient to convert the article of metal or metalloid or composite to an article or composite of refractory nitride. In addition, a method of applying a coating, such as a coating of an oxide, a carbide, or a carbo-nitride, to an article of metal or metalloid by microwave heating.

Method of nitriding refractory metal articles

DOEpatents

Tiegs, T.N.; Holcombe, C.E.; Dykes, N.L.; Omatete, O.O.; Young, A.C.

1994-03-15

A method of nitriding a refractory-nitride forming metal or metalloid articles and composite articles. A consolidated metal or metalloid article or composite is placed inside a microwave oven and nitrogen containing gas is introduced into the microwave oven. The metal or metalloid article or composite is heated to a temperature sufficient to react the metal or metalloid with the nitrogen by applying a microwave energy within the microwave oven. The metal or metalloid article or composite is maintained at that temperature for a period of time sufficient to convert the article of metal or metalloid or composite to an article or composite of refractory nitride. In addition, a method of applying a coating, such as a coating of an oxide, a carbide, or a carbo-nitride, to an article of metal or metalloid by microwave heating.

Method of nitriding, carburizing, or oxidizing refractory metal articles using microwaves

DOEpatents

Holcombe, Cressie E.; Dykes, Norman L.; Tiegs, Terry N.

1992-01-01

A method of nitriding an article of refractory-nitride-forming metal or metalloids. A consolidated metal or metalloid article is placed inside a microwave oven and nitrogen containing gas is introduced into the microwave oven. The metal or metalloid article is heated to a temperature sufficient to react the metal or metalloid with the nitrogen by applying a microwave energy within the microwave oven. The metal or metalloid article is maintained at that temperature for a period of time sufficient to convert the article of metal or metalloid to an article of refractory nitride. in addition, a method of applying a coating, such as a coating of an oxide, a carbide, or a carbo-nitride, to an article of metal or metalloid by microwave heating.

Method of nitriding, carburizing, or oxidizing refractory metal articles using microwaves

DOEpatents

Holcombe, C.E.; Dykes, N.L.; Tiegs, T.N.

1992-10-13

A method of nitriding an article of refractory-nitride-forming metal or metalloids. A consolidated metal or metalloid article is placed inside a microwave oven and nitrogen containing gas is introduced into the microwave oven. The metal or metalloid article is heated to a temperature sufficient to react the metal or metalloid with the nitrogen by applying a microwave energy within the microwave oven. The metal or metalloid article is maintained at that temperature for a period of time sufficient to convert the article of metal or metalloid to an article of refractory nitride. in addition, a method of applying a coating, such as a coating of an oxide, a carbide, or a carbo-nitride, to an article of metal or metalloid by microwave heating.

Wire winding increases lifetime of oxide coated cathodes

NASA Technical Reports Server (NTRS)

Kerslake, W.; Vargo, D.

1965-01-01

Refractory-metal heater base wound with a thin refractory metal wire increases the longevity of oxide-coated cathodes. The wire-wound unit is impregnated with the required thickness of metal oxide. This cathode is useful in magnetohydrodynamic systems and in electron tubes.

Compatibility of refractory materials for nuclear reactor poison control systems

NASA Technical Reports Server (NTRS)

Sinclair, J. H.

1974-01-01

Metal-clad poison rods have been considered for the control system of an advanced space power reactor concept studied at the NASA Lewis Research Center. Such control rods may be required to operate at temperatures of about 140O C. Selected poison materials (including boron carbide and the diborides of zirconium, hafnium, and tantalum) were subjected to 1000-hour screening tests in contact with candidate refractory metal cladding materials (including tungsten and alloys of tantalum, niobium, and molybdenum) to assess the compatibility of these materials combinations at the temperatures of interest. Zirconium and hafnium diborides were compatible with refractory metals at 1400 C, but boron carbide and tantalum diboride reacted with the refractory metals at this temperature. Zirconium diboride also showed promise as a reaction barrier between boron carbide and tungsten.

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

NASA Technical Reports Server (NTRS)

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.

Method for producing UO$sub 2$ loaded refractory metals

DOEpatents

Baker, R.D.; Hayter, S.W.; Lewis, H.D.

1973-12-11

A finely divided dispersion of UO/sub 2/ in tungsten or molybdenum is prepared by co-precipitating the metals from mixed aqueous solution with oxine. The co-precipitate thus formed is separated from the solution, dried, calcined, and finally reduced to UO/sub 2/ and refractory metal. (Official Gazette)

Benefit from autologous stem cell transplantation in primary refractory myeloma? Different outcomes in progressive versus stable disease

PubMed Central

Rosiñol, Laura; García-Sanz, Ramón; Lahuerta, Juan José; Hernández-García, Miguel; Granell, Miquel; de la Rubia, Javier; Oriol, Albert; Hernández-Ruiz, Belén; Rayón, Consuelo; Navarro, Isabel; García-Ruiz, Juan Carlos; Besalduch, Joan; Gardella, Santiago; Jiménez, Javier López; Díaz-Mediavilla, Joaquín; Alegre, Adrián; Miguel, Jesús San; Bladé, Joan

2012-01-01

Background Several studies of autologous stem cell transplantation in primary refractory myeloma have produced encouraging results. However, the outcome of primary refractory patients with stable disease has not been analyzed separately from the outcome of patients with progressive disease. Design and Methods In the Spanish Myeloma Group 2000 trial, 80 patients with primary refractory myeloma (49 with stable disease and 31 with progressive disease), i.e. who were refractory to initial chemotherapy, were scheduled for tandem transplants (double autologous transplant or a single autologous transplant followed by an allogeneic transplant). Patients with primary refractory disease included those who never achieved a minimal response (≥25% M-protein decrease) or better. Responses were assessed using the European Bone Marrow Transplant criteria. Results There were no significant differences in the rates of partial response or better between patients with stable or progressive disease. However, 38% of the patients with stable disease at the time of transplantation remained in a stable condition or achieved a minimal response after transplantation versus 7% in the group with progressive disease (P=0.0017) and the rate of early progression after transplantation was significantly higher among the group with progressive disease at the time of transplantation (22% versus 2%; P=0.0043). After a median follow-up of 6.6 years, the median survival after first transplant of the whole series was 2.3 years. Progression-free and overall survival from the first transplant were shorter in patients with progressive disease (0.6 versus 2.3 years, P=0.00004 and 1.1 versus 6 years, P=0.00002, respectively). Conclusions Our results show that patients with progressive refractory myeloma do not benefit from autologous transplantation, while patients with stable disease have an outcome comparable to those with chemosensitive disease. (ClinicalTrials.gov:NCT00560053) PMID:22058223

Improved Sand-Compaction Method for Lost-Foam Metal Casting

NASA Technical Reports Server (NTRS)

Bakhtiyarov, Sayavur I.; Overfelt, Ruel A.

2008-01-01

An improved method of filling a molding flask with sand and compacting the sand around a refractory-coated foam mold pattern has been developed for incorporation into the lost-foam metal-casting process. In comparison with the conventional method of sand filling and compaction, this method affords more nearly complete filling of the space around the refractory-coated foam mold pattern and more thorough compaction of the sand. In so doing, this method enables the sand to better support the refractory coat under metallostatic pressure during filling of the mold with molten metal.

Crucible cast from beryllium oxide and refractory cement is impervious to flux and molten metal

NASA Technical Reports Server (NTRS)

Jastrzebski, Z. D.

1966-01-01

Crucible from a mixture of a beryllium oxide aggregate and hydraulic refractory cement, and coated with an impervious refractory oxide will not deteriorate in the presence of fused salt- molten metal mixtures such as uranium- magnesium-zinc-halide salt systems. Vessels cast by this process are used in the flux reduction of oxides of thorium and uranium.

METHOD FOR COATING GRAPHITE WITH METALLIC CARBIDES

DOEpatents

Steinberg, M.A.

1960-03-22

A method for producing refractory coatings of metallic carbides on graphite was developed. In particular, the graphite piece to be coated is immersed in a molten solution of 4 to 5% by weight of zirconium, titanium, or niobium dissolved in tin. The solution is heated in an argon atmosphere to above 1400 deg C, whereby the refractory metal reacts with the surface of the graphite to form a layer of metalic carbide. The molten solution is cooled to 300 to 400 deg C, and the graphite piece is removed. Excess tin is wiped from the graphite, which is then heated in vacuum to above 2300 deg C. The tin vaporizes from the graphite surface, leaving the surface coated with a tenacious layer of refractory metallic carbide.

Copper-acrylic enamel serves as lubricant for cold drawing of refractory metals

NASA Technical Reports Server (NTRS)

Beane, C.; Karasek, F.

1966-01-01

Acrylic enamel spray containing metallic copper pigment lubricates refractory metal tubing during cold drawing operations so that the tubing surface remains free from scratches and nicks and does not seize in the die. Zirconium alloys, zirconium, tantalum alloys, niobium alloys, vanandium alloys and titanium alloys have been drawn using this lubricant.

Refractory lining for electrochemical cell

DOEpatents

Blander, Milton; Cook, Glenn M.

1987-01-01

Apparatus for processing a metallic fluid containing iron oxide, container for a molten metal including an electrically conductive refractory disposed for contact with the molten metal which contains iron oxide, an electrolyte in the form of a basic slag on top of the molten metal, an electrode in the container in contcat with the slag electrically separated from the refractory, and means for establishing a voltage across the refractory and the electrode to reduce iron oxide to iron at the surface of the refractory in contact with the iron oxide containing fluid. A process is disclosed for refining an iron product containing not more than about 10% by weight oxygen and not more than about 10% by weight sulfur, comprising providing an electrolyte of a slag containing one or more of calcium oxide, magnesium oxide, silica or alumina, providing a cathode of the iron product in contact with the electrolyte, providing an anode in contact with the electrolyte electrically separated from the cathode, and operating an electrochemical cell formed by the anode, the cathode and the electrolyte to separate oxygen or sulfur present in the iron product therefrom.

PARTITIONING OF THE REFRACTORY METALS, NICKEL AND CHROMIUM, IN COMBUSTION SYSTEMS

EPA Science Inventory

The partitioning of nickel (Ni) and Chromium (Cr) in combustion systems was investigated theoretically and experimentally. In comparison to other volatile and semi-volatile metals, both Ni and Cr are usually considered to be refractory (non-volatile). Theoretical predictions ba...

Method for ultra-fast boriding

DOEpatents

Erdemir, Ali; Sista, Vivekanand; Kahvecioglu, Ozgenur; Eryilmaz, Osman Levent

2017-01-31

An article of manufacture and method of forming a borided material. An electrochemical cell is used to process a substrate to deposit a plurality of borided layers on the substrate. The plurality of layers are co-deposited such that a refractory metal boride layer is disposed on a substrate and a rare earth metal boride conforming layer is disposed on the refractory metal boride layer.

Synthesis of refractory materials

DOEpatents

Holt, Joseph B.

1984-01-01

Refractory metal nitrides are synthesized during a self-propagating combustion process utilizing a solid source of nitrogren. For this purpose, a metal azide is employed, preferably NaN.sub.3. The azide is combusted with Mg or Ca, and a metal oxide is selected from Groups III-A, IV-A, III-B, IV-B, or a rare earth metal oxide. The mixture of azide, Ca or Mg and metal oxide is heated to the mixture's ignition temperature. At that temperature the mixture is ignited and undergoes self-sustaining combustion until the starter materials are exhausted, producing the metal nitride.

Synthesis of refractory materials

DOEpatents

Holt, J.B.

1983-08-16

Refractory metal nitrides are synthesized during a self-propagating combustion process utilizing a solid source of nitrogen. For this purpose, a metal azide is employed, preferably NaN/sub 3/. The azide is combusted with Mg or Ca, and a metal oxide is selected from Groups III-A, IV-A, III-B, IV-B, or a rare earth metal oxide. The mixture of azide, Ca or Mg and metal oxide is heated to the mixture's ignition temperature. At that temperature the mixture is ignited and undergoes self-sustaining combustion until the starter materials are exhausted, producing the metal nitride.

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

NASA Technical Reports Server (NTRS)

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.

Refractory metal particles in refractory inclusions in the Allende meteorite

NASA Technical Reports Server (NTRS)

Fuchs, L. H.; Blander, M.

1980-01-01

SEM and X-ray analysis were used to study refractory metal particles in five calcium-aluminum-rich inclusions in the Allende meteorite, and a complex variety of compositions and large departures from equilibrium were found. It is suggested that these particles could have been primordial condensates which were isolated from the nebula and from each other at different times by cocondensing oxides. Selective diffusion and/or oxidation of the more oxidizable metals (Mo, W, Fe, and Ni), phase segregations into different alloy phases (fcc, bcc, hcp, and, possibly, ordered phases), and the formation of metastable condensates could have been involved in the genesis of these materials

Emission spectrometric arcing procedure with minimal effect of chemical form of sample. [performed on refractory metal matrix composites

NASA Technical Reports Server (NTRS)

Gordon, W. A.

1975-01-01

Matrix effects related to the chemical form of analyzed materials were studied. An arc in argon was used which was buffered with silver chloride. The effect of chemical form was minimal for a variety of metals, oxides, and carbides representing the most refractory compounds and thermally stable metal-containing molecules. Only four of the most refractory materials known showed significant emission depressions due to incomplete volatilization in the arc system. These results are discussed in terms of vapor pressures of the solid materials placed on the anodes and dissociation reactions of the molecules in the gaseous environment.

Spontaneous growth of polarizing refractory metal ‘nano-fins’

NASA Astrophysics Data System (ADS)

Tai, M. C.; Gentle, A. R.; Arnold, M. D.; Cortie, M. B.

2018-03-01

Traditional polymer polarizers degrade in harsh environments and at high temperatures, reducing the polarization effect. In contrast, polarizers produced with refractory metals have vastly improved thermal stability and resistance to harsh environments but are expensive to fabricate. Here we demonstrate prototype refractory metal wire grid polarizers produced by co-sputtering molybdenum and aluminum under specific conditions. Removal of the aluminum through selective dissolution enables the nanostructure array to transmit light. The polarization spans 500-1100 nm and the extinction ratio significantly increases to >100. Possessing broadband polarization and sufficient extinction ratios, the new polarizing film has potential applications in coatings for sunglasses, windows, pyrometers, scientific instruments, and LCD panels.

High density crystalline boron prepared by hot isostatic pressing in refractory metal containers

DOEpatents

Hoenig, C.L.

1993-08-31

Boron powder is hot isostatically pressed in a refractory metal container to produce a solid boron monolith with a bulk density at least 2.22 g/cc and up to or greater than 2.34 g/cc. The refractory metal container is formed of tantalum, niobium, tungsten, molybdenum or alloys thereof in the form of a canister or alternatively plasma sprayed or chemical vapor deposited onto a powder compact. Hot isostatic pressing at 1,800 C and 30 PSI (206.8 MPa) argon pressure for four hours produces a bulk density of 2.34 g/cc. Complex shapes can be made.

High density crystalline boron prepared by hot isostatic pressing in refractory metal containers

DOEpatents

Hoenig, Clarence L.

1993-01-01

Boron powder is hot isostatically pressed in a refractory metal container to produce a solid boron monolith with a bulk density at least 2.22 g/cc and up to or greater than 2.34 g/cc. The refractory metal container is formed of tantalum, niobium, tungsten, molybdenum or alloys thereof in the form of a canister or alternatively plasma sprayed or chemical vapor deposited onto a powder compact. Hot isostatic pressing at 1800.degree. C. and 30 KSI (206.8 MPa) argon pressure for four hours produces a bulk density of 2.34 g/cc. Complex shapes can be made.

High density-high purity graphite prepared by hot isostatic pressing in refractory metal containers

DOEpatents

Hoenig, Clarence L.

1994-01-01

Porous graphite in solid form is hot isostatically pressed in a refractory metal container to produce a solid graphite monolith with a bulk density greater than or equal to 2.10 g/cc. The refractory metal container is formed of tantalum, niobium, tungsten, molybdenum or alloys thereof in the form of a canister or alternatively plasma sprayed, chemically vapor deposited, or coated by some other suitable means onto graphite. Hot isostatic pressing at 2200.degree. C. and 30 KSI (206.8 MPa) argon pressure for two hours produces a bulk density of 2.10 g/cc. Complex shapes can be made.

High density-high purity graphite prepared by hot isostatic pressing in refractory metal containers

DOEpatents

Hoenig, C.L.

1994-08-09

Porous graphite in solid form is hot isostatically pressed in a refractory metal container to produce a solid graphite monolith with a bulk density greater than or equal to 2.10 g/cc. The refractory metal container is formed of tantalum, niobium, tungsten, molybdenum or alloys thereof in the form of a canister or alternatively plasma sprayed, chemically vapor deposited, or coated by some other suitable means onto graphite. Hot isostatic pressing at 2,200 C and 30 KSI (206.8 MPa) argon pressure for two hours produces a bulk density of 2.10 g/cc. Complex shapes can be made. 1 fig.

High temperature barrier coatings for refractory metals

NASA Technical Reports Server (NTRS)

Malone, G. A.; Walech, T.

1995-01-01

Improvements in high temperature oxidation resistant metal coating technology will allow NASA and commercial entities to develop competitive civil space transport and communication systems. The success of investigations completed in this program will have a positive impact on broadening the technology base for high temperature materials. The work reported herein describes processes and procedures for successfully depositing coherent oxidation barrier coatings on refractory metals to prevent degradation under very severe operating environments. Application of the new technology developed is now being utilized in numerous Phase 3 applications through several prominent aerospace firms. Major achievements have included: (1) development of means to deposit thick platinum and rhodium coatings with lower stress and fewer microcracks than could be previously achieved; (2) development of processes to deposit thick adherent coatings of platinum group metals on refractory substrates that remain bonded through high temperature excursions and without need for intermediate coatings (bonding processes unique to specific refractory metals and alloys have been defined; (3) demonstration that useful alloys of refractory and platinum coatings can be made through thermal diffusion means; (4) demonstration that selected barrier coatings on refractory substrates can withstand severe oxidizing environments in the range of 1260 deg and 1760 deg C for long time periods essential to the life requirements of the hardware; and (5) successful application of the processes and procedures to prototype hardware. The results of these studies have been instrumental in improved thermal oxidation barrier coatings for the NASP propulsion system. Other Phase 3 applications currently being exploited include small uncooled thrusters for spacecraft and microsatellite maneuvering systems.

Improved high-temperature silicide coatings

NASA Technical Reports Server (NTRS)

Klopp, W. D.; Stephens, J. R.; Stetson, A. R.; Wimber, R. T.

1969-01-01

Special technique for applying silicide coatings to refractory metal alloys improves their high-temperature protective capability. Refractory metal powders mixed with a baked-out organic binder and sintered in a vacuum produces a porous alloy layer on the surface. Exposing the layer to hot silicon converts it to a silicide.

Low resistance barrier layer for isolating, adhering, and passivating copper metal in semiconductor fabrication

DOEpatents

Weihs, Timothy P.; Barbee, Jr., Troy W.

2002-01-01

Cubic or metastable cubic refractory metal carbides act as barrier layers to isolate, adhere, and passivate copper in semiconductor fabrication. One or more barrier layers of the metal carbide are deposited in conjunction with copper metallizations to form a multilayer characterized by a cubic crystal structure with a strong (100) texture. Suitable barrier layer materials include refractory transition metal carbides such as vanadium carbide (VC), niobium carbide (NbC), tantalum carbide (TaC), chromium carbide (Cr.sub.3 C.sub.2), tungsten carbide (WC), and molybdenum carbide (MoC).

Chemical Fracturing of Refractory-Metal Vessels

NASA Technical Reports Server (NTRS)

Campana, R. J.

1986-01-01

Localized reactions cause refractory-metal vessels to break up at predetermined temperatures. Device following concept designed to break up along predetermined lines into smaller pieces at temperature significantly below melting point of metal from which made. Possible applications include fire extinguishers that breakup to release extinguishing gas in enclosed areas, pressure vessels that could otherwise burst dangerously in fire, and self-destroying devices. Technique particularly suitable modification to already existing structures.

Barrier Coatings for Refractory Metals and Superalloys

DOE Office of Scientific and Technical Information (OSTI.GOV)

SM Sabol; BT Randall; JD Edington

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.more » 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.« less

Bright and durable field-emission source derived from frozen refractory-metal Taylor cones

DOE PAGES

Hirsch, Gregory

2017-02-22

A novel method for creating conical field-emission structures possessing unusual and desirable physical characteristics is described. This process is accomplished by solidification of electrostatically formed high-temperature Taylor cones created on the ends of laser melted refractory-metal wires. Extremely rapid freezing ensures that the resultant solid structures preserve the shape and surface smoothness of the flawless liquid Taylor-cones to a very high degree. The method also enables in situ and rapid restoration of the frozen cones to their initial pristine state after undergoing physical degradation during use. This permits maximum current to be delivered without excessive concern for any associated reductionmore » in field-emitter lifetime resulting from operation near or even above the damage threshold. In addition to the production of field emitters using polycrystalline wires as a substrate, the feasibility of producing monocrystalline frozen Taylor-cones having reproducible crystal orientation by growth on single-crystal wires was demonstrated. Finally, the development of the basic field-emission technology, progress to incorporate it into a pulsed electron gun employing laser-assisted field emission for ultrafast experiments, and some additional advances and opportunities are discussed.« less

Bright and durable field-emission source derived from frozen refractory-metal Taylor cones

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hirsch, Gregory

A novel method for creating conical field-emission structures possessing unusual and desirable physical characteristics is described. This process is accomplished by solidification of electrostatically formed high-temperature Taylor cones created on the ends of laser melted refractory-metal wires. Extremely rapid freezing ensures that the resultant solid structures preserve the shape and surface smoothness of the flawless liquid Taylor-cones to a very high degree. The method also enables in situ and rapid restoration of the frozen cones to their initial pristine state after undergoing physical degradation during use. This permits maximum current to be delivered without excessive concern for any associated reductionmore » in field-emitter lifetime resulting from operation near or even above the damage threshold. In addition to the production of field emitters using polycrystalline wires as a substrate, the feasibility of producing monocrystalline frozen Taylor-cones having reproducible crystal orientation by growth on single-crystal wires was demonstrated. Finally, the development of the basic field-emission technology, progress to incorporate it into a pulsed electron gun employing laser-assisted field emission for ultrafast experiments, and some additional advances and opportunities are discussed.« less

JOYO-1 Irradiation Test Campaign Technical Close-out, For Information

DOE Office of Scientific and Technical Information (OSTI.GOV)

G. Borges

2006-01-31

The JOYO-1 irradiation testing was designed to screen the irradiation performance of candidate cladding, structural and reflector materials in support of space reactor development. The JOYO-1 designation refers to the first of four planned irradiation tests in the JOYO reactor. Limited irradiated material performance data for the candidate materials exists for the expected Prometheus-1 duration, fluences and temperatures. Materials of interest include fuel element cladding and core materials (refractory metal alloys and silicon carbide (Sic)), vessel and plant structural materials (refractory metal alloys and nickel-base superalloys), and control and reflector materials (BeO). Key issues to be evaluated were long termmore » microstructure and material property stability. The JOYO-1 test campaign was initiated to irradiate a matrix of specimens at prototypical temperatures and fluences anticipated for the Prometheus-1 reactor [Reference (1)]. Enclosures 1 through 9 describe the specimen and temperature monitors/dosimetry fabrication efforts, capsule design, disposition of structural material irradiation rigs, and plans for post-irradiation examination. These enclosures provide a detailed overview of Naval Reactors Prime Contractor Team (NRPCT) progress in specific areas; however, efforts were in various states of completion at the termination of NRPCT involvement with and restructuring of Project Prometheus.« less

High density hexagonal boron nitride prepared by hot isostatic pressing in refractory metal containers

DOEpatents

Hoenig, Clarence L.

1992-01-01

Boron nitride powder with less than or equal to the oxygen content of starting powder (down to 0.5% or less) is hot isostatically pressed in a refractory metal container to produce hexagonal boron nitride with a bulk density greater than 2.0 g/cc. The refractory metal container is formed of tantalum, niobium, tungsten, molybdenum or alloys thereof in the form of a canister or alternatively plasma sprayed or chemical vapor deposited onto a powder compact. Hot isostatic pressing at 1800.degree. C. and 30 KSI (206.8 MPa) argon pressure for four hours produces a bulk density of 2.21 g/cc. Complex shapes can be made.

Steel refining with an electrochemical cell

DOEpatents

Blander, M.; Cook, G.M.

1988-05-17

Apparatus is described for processing a metallic fluid containing iron oxide, container for a molten metal including an electrically conductive refractory disposed for contact with the molten metal which contains iron oxide, an electrolyte in the form of a basic slag on top of the molten metal, an electrode in the container in contact with the slag electrically separated from the refractory, and means for establishing a voltage across the refractory and the electrode to reduce iron oxide to iron at the surface of the refractory in contact with the iron oxide containing fluid. A process is disclosed for refining an iron product containing not more than about 10% by weight oxygen and not more than about 10% by weight sulfur, comprising providing an electrolyte of a slag containing one or more of calcium oxide, magnesium oxide, silica or alumina, providing a cathode of the iron product in contact with the electrolyte, providing an anode in contact with the electrolyte electrically separated from the cathode, and operating an electrochemical cell formed by the anode, the cathode and the electrolyte to separate oxygen or sulfur present in the iron product therefrom. 2 figs.

Steel refining with an electrochemical cell

DOEpatents

Blander, M.; Cook, G.M.

1985-05-21

Disclosed is an apparatus for processing a metallic fluid containing iron oxide, container for a molten metal including an electrically conductive refractory disposed for contact with the molten metal which contains iron oxide, an electrolyte in the form of a basic slag on top of the molten metal, an electrode in the container in contact with the slag electrically separated from the refractory, and means for establishing a voltage across the refractory and the electrode to reduce iron oxide to iron at the surface of the refractory in contact with the iron oxide containing fluid. A process is disclosed for refining an iron product containing not more than about 10% by weight sulfur, comprising providing an electrolyte of a slag containing one or more of calcium oxide, magnesium oxide, silica or alumina, providing a cathode of the iron product in contact with the electrolyte, providing an anode in contact with the electrolyte electrically separated from the cathode, and operating an electrochemical cell formed by the anode, the cathode and the electrolyte to separate oxygen or sulfur present in the iron product therefrom.

Steel refining with an electrochemical cell

DOEpatents

Blander, Milton; Cook, Glenn M.

1988-01-01

Apparatus for processing a metallic fluid containing iron oxide, container for a molten metal including an electrically conductive refractory disposed for contact with the molten metal which contains iron oxide, an electrolyte in the form of a basic slag on top of the molten metal, an electrode in the container in contact with the slag electrically separated from the refractory, and means for establishing a voltage across the refractory and the electrode to reduce iron oxide to iron at the surface of the refractory in contact with the iron oxide containing fluid. A process is disclosed for refining an iron product containing not more than about 10% by weight oxygen and not more than about 10% by weight sulfur, comprising providing an electrolyte of a slag containing one or more of calcium oxide, magnesium oxide, silica or alumina, providing a cathode of the iron product in contact with the electrolyte, providing an anode in contact with the electrolyte electrically separated from the cathode, and operating an electrochemical cell formed by the anode, the cathode and the electrolyte to separate oxygen or sulfur present in the iron product therefrom.

Condensation of refractory metals in asymptotic giant branch and other stellar environments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schwander, D.; Berg, T.; Schönhense, G.

2014-09-20

The condensation of material from a gas of solar composition has been extensively studied, but less so condensation in the environment of evolved stars, which has been mainly restricted to major compounds and some specific element groups such as the Rare Earth elements. Also of interest, however, are refractory metals like Mo, Ru, Os, W, Ir, and Pt, which may condense to form refractory metal nuggets (RMNs) like the ones that have been found in association with presolar graphite. We have performed calculations describing the condensation of these elements in the outflows of s-process enriched AGB stars as well asmore » from gas enriched in r-process products. While in carbon-rich environments (C > O), the formation of carbides is expected to consume W, Mo, and V (Lodders and Fegley), the condensation sequence for the other refractory metals under these conditions does not significantly differ from the case of a cooling gas of solar composition. The composition in detail, however, is significantly different due to the completely different source composition. Condensation from an r-process enriched source differs less from the solar case. Elemental abundance ratios of the refractory metals can serve as a guide for finding candidate presolar grains among the RMNs in primitive meteorites—most of which have a solar system origin—for confirmation by isotopic analysis. We apply our calculations to the case of the four RMNs found by Croat et al., which may very well be presolar.« less

Surface properties of thermionic electrodes

NASA Technical Reports Server (NTRS)

Stickney, R. E.

1972-01-01

A quasi-equilibrium model which provides semiquantitative predictions of the oxygen reaction with refractory metals was developed at high temperature and low pressure. Extensive experimental data was obtained on adsorption and work function properties for a wide variety of adsorbates (Cs, K, Na, I, Br, Cl, and O) on several refractory metals (W, Ta, Mo, and Re). Conclusions and recommendations for research on alkali metal adsorption, oxygen adsorption, and adsorption of cesium - oxygen mixtures are included.

Preliminary Investigations of Joining Technologies for Attaching Refractory Metals to Ni-Based Superalloys

NASA Technical Reports Server (NTRS)

Gould, Jerry E.; Ritzert, Frank J.; Loewenthal, William S.

2006-01-01

In this study, a range of joining technologies has been investigated for creating attachments between refractory metal and Ni-based superalloys. Refractory materials of interest include Mo-47%Re, T-111, and Ta-10%W. The Ni-based superalloys include Hastelloy X and MarM 247. During joining with conventional processes, these materials have potential for a range of solidification and intermetallic formation-related defects. For this study, three non-conventional joining technologies were evaluated. These included inertia welding, electro-spark deposition (ESD) welding, and magnetic pulse welding (MPW). The developed inertia welding practice closely paralleled that typically used for the refractory metals alloys. Metallographic investigations showed that forging during inertia welding occurred predominantly on the nickel base alloy side. It was also noted that at least some degree of forging on the refractory metal side of the joint was necessary to achieve consistent bonding. Both refractory metals were readily weldable to the Hastelloy X material. When bonding to the MarM 247, results were inconsistent. This was related to the higher forging temperatures of the MarM 247, and subsequent reduced deformation on that material during welding. ESD trials using a Hastelloy X filler were successful for all material combinations. ESD places down very thin (5- to 10- m) layers per pass, and interactions between the substrates and the fill were limited (at most) to that layer. For the refractory metals, the fill only appeared to wet the surface, with minimal dilution effects. Microstructures of the deposits showed high weld metal integrity with maximum porosity on the order of a few percent. Some limited success was also obtained with MPW. In these trials, only the T-111 tubes were used. Joints were possible for the T-111 tube to the Hastelloy X bar stock, but the stiffness of the tube (resisting collapse) necessitated the use of very high power levels. These power levels resulted in damage to the equipment (concentrator) during welding. It is of note that the joint made showed the typical wavy bond microstructure associated with magnetic pulse/explosion bond joints. Joints were not possible between the T-111 tube and the MarM 247 bar stock. In this case, the MarM 247 shattered before sufficient impact forces could be developed for bonding.

METHOD OF JOINING CARBIDES TO BASE METALS

DOEpatents

Krikorian, N.H.; Farr, J.D.; Witteman, W.G.

1962-02-13

A method is described for joining a refractory metal carbide such as UC or ZrC to a refractory metal base such as Ta or Nb. The method comprises carburizing the surface of the metal base and then sintering the base and carbide at temperatures of about 2000 deg C in a non-oxidizing atmosphere, the base and carbide being held in contact during the sintering step. To reduce the sintering temperature and time, a sintering aid such as iron, nickel, or cobait is added to the carbide, not to exceed 5 wt%. (AEC)

Simulation of Phonon Spectra in Three-Component Two-Dimensional Crystals of Refractory-Metal Dichalcogenides

NASA Astrophysics Data System (ADS)

Alexeev, A. Yu.; Krivosheeva, A. V.; Shaposhnikov, V. L.; Borisenko, V. E.

2017-09-01

A model for ab initio calculation of the phonon properties of three-component solid solutions of refractory-metal dichalcogenides was developed based on the assumption that displacements of the same type of chalcogen atoms and decoupled displacements of the metal atoms were identical. The calculated phonon frequencies at the Γ-point for monomolecular layers of MoS2-xSex and MoS2-xTex agreed with existing experimental Raman spectra.

Spent refractory reuse as a slag conditioning additive in the EAF

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bennett, James P.; Kwong, Kyei-Sing; Krabbe, Rick

2000-01-01

Refractories removed from service in EAF applications are typically landfilled. A joint USDOE and Steel Manufacturers Association program involving industrial cooperators is evaluating spent refractory recycling/reuse. A review of current recycling practices and a review of progress towards controlling EAF slag chemistry and properties with the additions of basic spent refractories will be discussed.

Defects in metal crystals. Progress report, May 1, 1980-April 30, 1981

DOE Office of Scientific and Technical Information (OSTI.GOV)

Seidman, D.N.

1981-01-01

During the past year a strong endeavor was made to redirect the efforts of the research group to determine atomic mechanisms for the formation of metal silicides, among other problems, produced as a result of: (a) ion or electron irradiation of metal-silicon sandwiches; and (b) the ion irradiation of subsaturated binary alloys containing silicon. In addition, an appreciable component of the research is aimed at understanding the atomic mechanisms responsible for radiation-induced segregation and RIP in a wide range of fast-neutron irradiated refractory metals and alloys. In these same neutron irradiated specimens a search is being made for the speciesmore » that are responsible for the nucleation of voids. In particular, the voids are being examined, by the atom-probe field-ion microscope technique, for the interstitial impurities helium, carbon, nitrogen and oxygen. Evidence was obtained for the presence of carbon in a void of a fast neutron-irradiated molybdenum (titanium) alloy.« less

Refractory thermowell for continuous high temperature measurement of molten metal

DOEpatents

Thiesen, Todd J.

1992-01-01

An apparatus for the continuous high temperature measurement of materials in vessels lined with rammed or cast refractory materials. A refractory housing member is integral with the refractory lining of the vessel and contains a plurality of high temperature sensing means, such as thermocouples. A face of the housing is flush with the refractory lining and contacts the high temperature material contained in the vessel. Continuous temperature measurement is achieved by a means which is coupled to the thermocouples for indicating the temperature.

Aluminum reduction cell electrode

DOEpatents

Goodnow, Warren H.; Payne, John R.

1982-01-01

The invention is directed to cathode modules comprised of refractory hard metal materials, such as TiB.sub.2, for an electrolytic cell for the reduction of alumina wherein the modules may be installed and replaced during operation of the cell and wherein the structure of the cathode modules is such that the refractory hard metal materials are not subjected to externally applied forces or rigid constraints.

Refractory metal alloys and composites for space nuclear power systems

NASA Technical Reports Server (NTRS)

Titran, Robert H.; Stephens, Joseph R.; Petrasek, Donald W.

1988-01-01

Space power requirements for future NASA and other U.S. missions will range from a few kilowatts to megawatts of electricity. Maximum efficiency is a key goal of any power system in order to minimize weight and size so that the Space Shuttle may be used a minimum number of times to put the power supply into orbit. Nuclear power has been identified as the primary power source to meet these high levels of electrical demand. One method to achieve maximum efficiency is to operate the power supply, energy conservation system, and related components at relatively high temperatures. For systems now in the planning stages, design temperatures range from 1300 K for the immediate future to as high as 1700 K for the advanced systems. NASA Lewis Research Center has undertaken a research program on advanced technology of refractory metal alloys and composites that will provide baseline information for space power systems in the 1900's and the 21st century. Special emphasis is focused on the refractory metal alloys of niobium and on the refractory metal composites which utilize tungsten alloy wires for reinforcement. Basic research on the creep and creep-rupture properties of wires, matrices, and composites are discussed.

Development and Implementation of the Casting of Rods Made of Refractory Cast Alloys

NASA Astrophysics Data System (ADS)

Kabanov, I. V.; Urin, S. L.; Ivanyuk, A. S.; Nesterov, A. N.; Bogdanov, S. V.

2017-12-01

The problems of the production of a so-called casting rod blank made of a refractory casting alloy in the vacuum induction furnaces of AO Metallurgical Plant Electrostal are considered. A unique technology of casting and subsequent treatment of as-cast rod blanks made of refractory alloys is developed, tested, and optimized. As a result of the developed and performed measures for the production of metal products in the Consarc furnace, the ingot-to-product yield increases by 15% as compared to metal casting in an ISV-1.0 furnace. As a result, we have widened the range of cast alloy grades and are going to cast metals for the manufacture of blanks of other sizes and ranges of alloy an steel grades.

Background research in support of the new grant proposal: Research consortium for X-ray topography on line X-19 at NSLS

NASA Astrophysics Data System (ADS)

Bilello, J. C.

1983-11-01

The status of the construction and installation of components of the synchrotron topography station is reported as well as progress in the development of hardware for interfacing and software for interactively controlling the 13 motors which automate the facility. Research focuses on the problem of X-ray optics and on techniques for applying topography to materials science. There is colaboration with other researchers in studying the nature of brittle fracture of refractory metals and in interpreting contact in the vicinity of crack tips.

Aluminum reduction cell electrode

DOEpatents

Goodnow, W.H.; Payne, J.R.

1982-09-14

The invention is directed to cathode modules comprised of refractory hard metal materials, such as TiB[sub 2], for an electrolytic cell for the reduction of alumina wherein the modules may be installed and replaced during operation of the cell and wherein the structure of the cathode modules is such that the refractory hard metal materials are not subjected to externally applied forces or rigid constraints. 9 figs.

Quasi-static Tensile and Compressive Behavior of Nanocrystalline Tantalum based on Miniature Specimen Testing—Part I: Materials Processing and Microstructure

NASA Astrophysics Data System (ADS)

Ligda, J.; Scotto D'Antuono, D.; Taheri, M. L.; Schuster, B. E.; Wei, Q.

2016-11-01

Grain size reduction of metals into ultrafine-grained (UFG, grain size 100 nm < d < 1000 nm) and nanocrystalline (NC, d < 100 nm) regimes results in considerable increase in strength along with other changes in mechanical behavior such as vanishing strain hardening and limited ductility. Severe plastic deformation (SPD) has been among the favored technologies for the fabrication of UFG/NC metals. Primary past research efforts on SPD UFG/NC metals have been focused on easy-to-work metals, especially face-centered cubic metals such as copper, nickel, etc., and the limited efforts on body-centered cubic metals have mainly focused on high strain rate behavior where these metals are shown to deform via adiabatic shear bands. Except for the work on Fe, only a few papers can be found associated with UFG/NC refractory metals. In the first part of the present work (Part I), high-pressure torsion (HPT) is used to process UFG/NC tantalum, a typical refractory metal. The microstructure of the HPT disk as a function of radial location as well as orientation will be examined. In the subsequent part (Part II), the location-specific mechanical behavior will be presented and discussed. It is suggested that refractory metals such as Ta are ideal to employ SPD technology for microstructure refinement because of the extremely high melting point and relatively good workability.

Materials Chemistry Issues in the Development of a Single-Crystal Solar/Thermal Refractive Secondary Concentrator

NASA Technical Reports Server (NTRS)

Jacobson, Nathan S.; Biering, Robert C.

2005-01-01

A translucent crystal concentrates and transmits energy to a heat exchanger, which in turn heats a propellant gas, working gas of a dynamic power system, or a thermopile. Materials are the limiting issue in such a system. Central is the durability of the crystal, which must maintain the required chemical, physical/optical, and mechanical properties as it is heated and cooled. This report summarizes available data to date on the materials issues with this system. We focus on the current leading candidate materials, which are sapphire (Al2O3) for higher temperatures and silica (SiO2) for lower temperatures. We use data from thermochemical calculations; laboratory coupon tests with silica and sapphire; and system tests with sapphire. The required chemical properties include low-vapor pressure and interfacial stability with supporting structural materials. Optical properties such as transmittance and index of refraction must be maintained. Thermomechanical stability is a major challenge for a large, single-crystal ceramic and has been discussed in another report. In addition to the crystal, other materials in the proposed system include refractory metals (Nb, Ta, Mo, W, and Re), carbon (C), and high-temperature ceramic insulation. The major issue here is low levels of oxygen, which lead to volatile refractory metal oxides and rapid consumption of the refractory metal. Interfacial reactions between the ceramic crystal and refractory metal are also discussed. Finally, high-temperature ceramic insulating materials are also likely to be used in this system. Outgassing is a major issue for these materials. The products of outgassing are typically reactive with the refractory metals and must be minimized.

Role of levetiracetam in refractory seizures due to a rare progressive myoclonic epilepsy: Lafora body disease

PubMed Central

Hashmi, Mubashira; Saleem, Feroza; Mustafa, Muhammad Shahid; Sheerani, Mughis; Ehtesham, Zeeshan; Siddiqui, Khurram

2010-01-01

Lafora disease is one of the rare, most fatal progressive myoclonic epilepsies reported. We present a case of a teenager with intractable seizures and progressive mental decline, diagnosed as Lafora body disease on axillary skin biopsy. He was admitted with status epilepticus with refractory myoclonic and generalised tonic clonic seizures. Despite on maximum doses of multiple antiepileptic drugs and infusions of propofol and midazolam, his seizures were refractory to all forms of medical therapy tried. Levetiracetam (LEV), a pyrrolidine derivative, was introduced; he showed a prompt response and was weaned off successfully from infusions of anticonvulsants and mechanical ventilation within 48 h of introduction of LEV, followed by an almost seizure-free status. PMID:22791845

Mineral resource of the month: kyanite

USGS Publications Warehouse

Potter, Michael J.

2007-01-01

Kyanite and related minerals are used in making refractories, which are materials that can withstand high-temperature environments, generally in excess of 1,100 degrees Celsius. Refractories form an inner lining to furnaces, kilns and other containers with which molten metals and glass come into contact. Fifty to 70 percent of global refractory consumption is related to the steel industry.

Grain refinement in heavy rare earth element-free sintered Nd–Fe–B magnets by addition of a small amount of molybdenum

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Jin Woo; Lee, Won Suk; Byun, Jong Min

2015-05-07

We employed a modified refractory-metal-addition method to achieve higher coercivity and remanence in heavy rare earth element (HREE)-free Nd–Fe–B sintered magnets. This process involved inducing the formation of a homogeneous secondary phase at the grain boundaries during sintering, making it possible to control the intergrain diffusion by adding small amounts of Mo, a refractory metal. To control the microstructure of the secondary phase effectively, a metal organic compound of the refractory metal was coated on the surfaces of the particles of an HREE-free Nd–Fe–B powder. The average grain size after this process was 5.60 μm, which was approximately 1.8 μm smaller thanmore » that of the HREE-free sintered Nd–Fe–B magnets (7.4 μm). The coercivity of the magnets prepared through this process could be increased from 11.88 kOe to 13.91 kOe without decreasing their remanence.« less

Laboratory studies of refractory metal oxide smokes

NASA Technical Reports Server (NTRS)

Nuth, Joseph A.; Nelson, R. N.; Donn, Bertram

1989-01-01

Studies of the properties of refractory metal oxide smokes condensed from a gas containing various combinations of SiH4, Fe(CO)5, Al(CH3)3, TiCl4, O2 and N2O in a hydrogen carrier stream at 500 K greater than T greater than 1500 K were performed. Ultraviolet, visible and infrared spectra of pure, amorphous SiO(x), FeO(x), AlO(x) and TiO(x) smokes are discussed, as well as the spectra of various co-condensed amorphous oxides, such as FE(x)SiO(y) or Fe(x)AlO(y). Preliminary studies of the changes induced in the infrared spectra of iron-containing oxide smokes by vacuum thermal annealing suggest that such materials become increasingly opaque in the near infrared with increased processing: hydration may have the opposite effect. More work on the processing of these materials is required to confirm such a trend: this work is currently in progress. Preliminary studies of the ultraviolet spectra of amorphous Si2O3 and MgSiO(x) smokes revealed no interesting features in the region from 200 to 300 nm. Studies of the ultraviolet spectra of both amorphous, hydrated and annealed SiO(x), TiO(x), AlO(x) and FeO(x) smokes are currently in progress. Finally, data on the oxygen isotopic composition of the smokes produced in the experiments are presented, which indicate that the oxygen becomes isotopically fractionated during grain condensation. Oxygen in the grains is as much as 3 percent per amu lighter than the oxygen in the original gas stream. The authors are currently conducting experiments to understand the mechanism by which fractionation occurs.

Development Study of Cartridge/Crucible Tube Materials

NASA Technical Reports Server (NTRS)

McKechnie, Timothy N.; ODell, Scott J.

1998-01-01

The limitations of traditional alloys and the desire for improved performance for components is driving the increased utilization of refractory metals in tile space industry. From advanced propulsion systems to high temperature furnace components for microgravity processing, refractory metals are being used for their high melting temperatures and inherent chemical stability. Techniques have been developed to produce near net shape refractory metal components utilizing vacuum plasma spraying. Material utilization is very high, and laborious machining can be avoided. As-spray formed components have been tested and found to perform adequately. However, increased mechanical and thermal properties are needed. To improve these properties, post processing thermal treatments such as hydrogen sintering and vacuum annealing have been performed. Components formed from alloys of tungsten, rhenium, tantalum, niobium, and molybdenum are discussed and a metallurgical analyses detailing the results are presented. A qualitative comparison of mechanical properties is also included.

Refractory electrodes for joule heating and methods of using same

DOEpatents

Lamar, David A.; Chapman, Chris C.; Elliott, Michael L.

1998-01-01

A certain group of electrically conductive refractory materials presently known for use in high temperature applications as throat constructions, melter sidewalls, forehearth, stacks, port sills, hot face lining for slagging coal gasifiers, slag runners, and linings for nuclear waste encapsulation furnaces may be used as electrodes permitting joule heating at temperatures in excess of 1200 C. in excess of about 4400 hours even in the presence of transition group element(s). More specifically, the invention is an electrode for melting earthen materials, wherein the electrode is made from an electrically conductive refractory material, specifically at least one metal oxide wherein the metal is selected from the group consisting of chrome, ruthenium, rhodium, tin and combinations thereof.

Chlorination of UO 2, PuO 2 and rare earth oxides using ZrCl 4 in LiCl-KCl eutectic melt

NASA Astrophysics Data System (ADS)

Sakamura, Yoshiharu; Inoue, Tadashi; Iwai, Takashi; Moriyama, Hirotake

2005-04-01

A new chlorination method using ZrCl 4 in a molten salt bath has been investigated for the pyrometallurgical reprocessing of nuclear fuels. ZrCl 4 has a high reactivity with oxygen but is not corrosive to refractory metals such as steel. Rare earth oxides (La 2O 3, CeO 2, Nd 2O 3 and Y 2O 3) and actinide oxides (UO 2 and PuO 2) were allowed to react with ZrCl 4 in a LiCl-KCl eutectic salt at 773 K to give a metal chloride solution and a precipitate of ZrO 2. An addition of zirconium metal as a reductant was effective in chlorinating the dioxides. When the oxides were in powder form, the reaction was observed to progress rapidly. Cyclic voltammetry provided a convenient way of establishing when the reaction was completed. It was demonstrated that the ZrCl 4 chlorination method, free from corrosive gas, was very simple and useful.

PREPARATION OF PLUTONIUM

DOEpatents

Kolodney, M.

1959-07-01

Methods are presented for the electro-deposition of plutonium from fused mixtures of plutonium halides and halides of the alkali metals and alkaline earth metals. Th salts, preferably chlorides and with the plutonium prefer ably in the trivalent state, are placed in a refractory crucible such as tantalum or molybdenam and heated in a non-oxidizing atmosphere to 600 to 850 deg C, the higher temperatatures being used to obtain massive plutonium and the lower for the powder form. Electrodes of graphite or non reactive refractory metals are used, the crucible serving the cathode in one apparatus described in the patent.

Electromagnetic valve for controlling the flow of molten, magnetic material

DOEpatents

Richter, T.

1998-06-16

An electromagnetic valve for controlling the flow of molten, magnetic material is provided, which comprises an induction coil for generating a magnetic field in response to an applied alternating electrical current, a housing, and a refractory composite nozzle. The nozzle is comprised of an inner sleeve composed of an erosion resistant refractory material (e.g., a zirconia ceramic) through which molten, magnetic metal flows, a refractory outer shell, and an intermediate compressible refractory material, e.g., unset, high alumina, thermosetting mortar. The compressible refractory material is sandwiched between the inner sleeve and outer shell, and absorbs differential expansion stresses that develop within the nozzle due to extreme thermal gradients. The sandwiched layer of compressible refractory material prevents destructive cracks from developing in the refractory outer shell. 5 figs.

Electromagnetic valve for controlling the flow of molten, magnetic material

DOEpatents

Richter, Tomas

1998-01-01

An electromagnetic valve for controlling the flow of molten, magnetic material is provided, which comprises an induction coil for generating a magnetic field in response to an applied alternating electrical current, a housing, and a refractory composite nozzle. The nozzle is comprised of an inner sleeve composed of an erosion resistant refractory material (e.g., a zirconia ceramic) through which molten, magnetic metal flows, a refractory outer shell, and an intermediate compressible refractory material, e.g., unset, high alumina, thermosetting mortar. The compressible refractory material is sandwiched between the inner sleeve and outer shell, and absorbs differential expansion stresses that develop within the nozzle due to extreme thermal gradients. The sandwiched layer of compressible refractory material prevents destructive cracks from developing in the refractory outer shell.

Platinum Group Coatings for Refractory Metals

DTIC Science & Technology

1984-06-01

temperatures and deposition was very slow. We decided to try iridium hexaflouride, Siridium trichloride hydrate, iridiuw carbonyl and tris-acetyl acetonato...T:*ouu sue. CO. Rhenium Refractory Metals 03 1 d.pRsiý C rg Iridium Coatings 2i 8 bapo i 10. ASSTRACT Won#~.. on mov ofot~sfte.. iad k.dhItfV by b...b q Oxidation resistant coatings of iridium on rhenium substrates have been produced by chemical vapor deposition from an iridium acetyl acetonate

Chronopotentiometry of Refractory Metals, Actinides and Oxyanions in Molten Salts: A Review

DTIC Science & Technology

1992-09-01

disappaared. No new wave appeared which could be attributed to the nitrosonium , NO+, ion . The nitronium ion , N02+, could not be detected in the melt...electrodeposit- ion of coherent deposits of refractory metals from solutions in fused electrolytes. 2.1. Titanium. The electrochemical oxidation of Ti(II...the higher valent niobium ions were found to be electroactive. The reduction process was a reversible, one electron step with the product soluble in the

Antiangiogenic therapy for patients with aggressive or refractory advanced non-small cell lung cancer in the second-line setting.

PubMed

Reck, Martin; Garassino, Marina Chiara; Imbimbo, Martina; Shepherd, Frances A; Socinski, Mark A; Shih, Jin-Yuan; Tsao, Anne; Lee, Pablo; Winfree, Katherine B; Sashegyi, Andreas; Cheng, Rebecca; Varea, Rocio; Levy, Benjamin; Garon, Edward

2018-06-01

A majority of patients with advanced or metastatic non-small cell lung cancer (NSCLC) will experience disease progression after first-line therapy. Patients who have advanced NSCLC that is especially aggressive, which is defined as disease that rapidly progresses on first-line treatment or disease that is refractory to first-line treatment, have a critical unmet medical need. These patients have a poor prognosis in the second-line setting. Several studies have recently shown that treatment with an antiangiogenic therapy may benefit these patients. This review summarizes the approved antiangiogenic therapies for the treatment of patients with advanced NSCLC in the second-line setting, specifically focusing on the outcomes from subgroups of patients with rapidly progressing or refractory disease. Several antiangiogenic agents, as monotherapy or in combination with other treatments, have been or are currently being studied in patients with advanced NSCLC. Antiangiogenics that are approved for use in patients with advanced NSCLC are limited to bevacizumab in combination with chemotherapy (nonsquamous NSCLC), ramucirumab in combination with docetaxel (all histologies), and nintedanib in combination with docetaxel (adenocarcinoma histology). This review focuses on the efficacy, safety, and quality of life outcomes in the subpopulation of patients with rapidly progressing or refractory NSCLC treated with approved antiangiogenic therapies in the second-line setting. We also discuss the impact of newly approved immunotherapy agents on the outcomes of patients with aggressive or refractory disease. Studies in progress and planned future research will determine if combination treatment with antiangiogenics and immunotherapies will benefit patients with aggressive, advanced NSCLC. Copyright © 2018. Published by Elsevier B.V.

Refractory pulmonary sarcoidosis - proposal of a definition and recommendations for the diagnostic and therapeutic approach.

PubMed

Korsten, Peter; Strohmayer, Katharina; Baughman, Robert P; Sweiss, Nadera J

2016-03-01

Patients with sarcoidosis undergo spontaneous remission or may be effectively controlled with glucocorticoids alone in many cases. Progressive and refractory pulmonary sarcoidoisis constitute more than 10% of patients seen at specialized centers. Pulmonary fibrosis and associated complications, such as infections and pulmonary hypertension are leading causes of mortality. No universal definition of refractoriness exists, we therefore propose classifying patients as having refractory disease when the following criteria are fulfilled: (1) progressive disease despite at least 10 mg of prednisolone or equivalent for at least three months and need for additional disease-modifying anti-sarcoid drugs due to lack of efficacy, drug toxicity or intolerability and (2) treatment started for significant impairment of life due to progressive pulmonary symptoms. Both criteria should be fulfilled. Treatment options in addition to or instead of glucocorticoids for these patients include second- (methotrexate, azathioprine, leflunomide) and third-line agents (infliximab, adalimumab). Other immunmodulating agents can be used, but the evidence is very limited. Newer agents with anti-fibrotic properties, such as pirfenidone or nintedanib, might hold promise also for the pulmonary fibrosis seen in sarcoidosis. Treating physicians have to actively look for potentially treatable complications, such as pulmonary hypertension, cardiac disease or infections before patients should be classified as treatment-refractory. Ultimately, lung transplantation has to be considered as treatment option for patients not responding to medical therapy. In this review, we aim to propose a new definition of refractoriness, describe the associated clinical features and suggest the therapeutic approach.

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

DTIC Science & Technology

2012-03-01

Miracle Metals Branch Metals , Ceramics & Nondestructive Evaluation Division O.N. Senkov and S.V. Senkova UES Inc. MARCH 2012...Manager PAUL RET, Branch Chief Metals Branch Metals Branch Metals , Ceramics & Nondestructive Evaluation Division Metals , Ceramics...Nondestructive Evaluation Division //SIGNED// ______________________________________ CHARLES H. WARD, Division Chief Metals , Ceramics

Chromia refractory brick with carbon treatment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bennett, James P.; Kwong, Kyei-Sing

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 performsmore » 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.« less

Production of crystalline refractory metal oxides containing colloidal metal precipitates and useful as solar-effective absorbers

DOEpatents

Narayan, Jagdish; Chen, Yok

1983-01-01

This invention is a new process for producing refractory crystalline oxides having improved or unusual properties. The process comprises the steps of forming a doped-metal crystal of the oxide; exposing the doped crystal in a bomb to a reducing atmosphere at superatmospheric pressure and a temperature effecting precipitation of the dopant metal in the crystal lattice of the oxide but insufficient to effect net diffusion of the metal out of the lattice; and then cooling the crystal. Preferably, the cooling step is effected by quenching. The process forms colloidal precipitates of the metal in the oxide lattice. The process may be used, for example, to produce thermally stable black MgO crystalline bodies containing magnetic colloidal precipitates consisting of about 99% Ni. The Ni-containing bodies are solar-selective absorbers, having a room-temperature absorptivity of about 0.96 over virtually all of the solar-energy spectrum and exhibiting an absorption edge in the region of 2 .mu.m. The process parameters can be varied to control the average size of the precipitates. The process can produce a black MgO crystalline body containing colloidal Ni precipitates, some of which have the face-centered-cubic structure and others of which have the body-centered cubic structure. The products of the process are metal-precipitate-containing refractory crystalline oxides which have improved or unique optical, mechanical, magnetic, and/or electronic properties.

Refractory metals welded or brazed with tungsten inert gas equipment

NASA Technical Reports Server (NTRS)

Wisner, J. P.

1965-01-01

Appropriate brazing metals and temperatures facilitate the welding or brazing of base metals with tungsten inert gas equipment. The highest quality bond is obtained when TIG welding is performed in an inert atmosphere.

Refractory electrodes for joule heating and methods of using same

DOEpatents

Lamar, D.A.; Chapman, C.C.; Elliott, M.L.

1998-05-12

A certain group of electrically conductive refractory materials presently known for use in high temperature applications as throat constructions, melter sidewalls, forehearth, stacks, port sills, hot face lining for slagging coal gasifiers, slag runners, and linings for nuclear waste encapsulation furnaces may be used as electrodes permitting joule heating at temperatures in excess of 1,200 C in excess of about 4400 hours even in the presence of transition group element(s). More specifically, the invention is an electrode for melting earthen materials, wherein the electrode is made from an electrically conductive refractory material, specifically at least one metal oxide wherein the metal is selected from the group consisting of chrome, ruthenium, rhodium, tin and combinations thereof. 2 figs.

Net Shaped Component Fabrication of Refractory Metal Alloys using Vacuum Plasma Spraying

NASA Technical Reports Server (NTRS)

Sen, S.; ODell, S.; Gorti, S.; Litchford, R.

2006-01-01

The vacuum plasma spraying (VPS) technique was employed to produce dense and net shaped components of a new tungsten-rhenium (W-Re) refractory metal alloy. The fine grain size obtained using this technique enhanced the mechanical properties of the alloy at elevated temperatures. The alloy development also included incorporation of thermodynamically stable dispersion phases to pin down grain boundaries at elevated temperatures and thereby circumventing the inherent problem of recrystallization of refractory alloys at elevated temperatures. Requirements for such alloys as related to high temperature space propulsion components will be discussed. Grain size distribution as a function of cooling rate and dispersion phase loading will be presented. Mechanical testing and grain growth results as a function of temperature will also be discussed.

Chemical properties and methods of analysis of refractory compounds

NASA Technical Reports Server (NTRS)

Samsonov, G. V. (Editor); Frantsevich, I. N. (Editor); Yeremenko, V. N. (Editor); Nazarchuk, T. N. (Editor); Popova, O. I. (Editor)

1978-01-01

Reactions involving refractory metals and the alloys based on them are discussed. Chemical, electrochemical, photometric, spectrophotometric, and X-ray analysis are among the methods described for analyzing the results of the reactions and for determining the chemical properties of these materials.

THERMAL DECOMPOSITION OF URANIUM COMPOUNDS

DOEpatents

Magel, T.T.; Brewer, L.

1959-02-10

A method is presented of preparing uranium metal of high purity consisting contacting impure U metal with halogen vapor at between 450 and 550 C to form uranium halide vapor, contacting the uranium halide vapor in the presence of H/sub 2/ with a refractory surface at about 1400 C to thermally decompose the uranium halides and deposit molten U on the refractory surface and collecting the molten U dripping from the surface. The entire operation is carried on at a sub-atmospheric pressure of below 1 mm mercury.

Metal alloy coatings and methods for applying

DOEpatents

Merz, Martin D.; Knoll, Robert W.

1991-01-01

A method of coating a substrate comprises plasma spraying a prealloyed feed powder onto a substrate, where the prealloyed feed powder comprises a significant amount of an alloy of stainless steel and at least one refractory element selected from the group consisting of titanium, zirconium, hafnium, niobium, tantalum, molybdenum, and tungsten. The plasma spraying of such a feed powder is conducted in an oxygen containing atmosphere and forms an adherent, corrosion resistant, and substantially homogenous metallic refractory alloy coating on the substrate.

Metal- and intermetallic-matrix composites for aerospace propulsion and power systems

NASA Technical Reports Server (NTRS)

Doychak, J.

1992-01-01

The requirements for high specific strength refractory materials of prospective military, civil, and space propulsion systems are presently addressed in the context of emerging capabilities in metal- and intermetallic-matrix composites. The candidate systems encompass composite matrix compositions of superalloy, Nb-Zr refractory alloy, Cu-base, and Ti-base alloy types, as well as such intermetallics as TiAl, Ti3Al, NiAl, and MoSi2. The brittleness of intermetallic matrices remains a major consideration, as does their general difficulty of fabrication.

Reusable high-temperature heat pipes and heat pipe panels

NASA Technical Reports Server (NTRS)

Camarda, Charles J. (Inventor); Ransone, Philip O. (Inventor)

1989-01-01

A reusable, durable heat pipe which is capable of operating at temperatures up to about 3000 F in an oxidizing environment and at temperatures above 3000 F in an inert or vacuum environment is produced by embedding a refractory metal pipe within a carbon-carbon composite structure. A reusable, durable heat pipe panel is made from an array of refractory-metal pipes spaced from each other. The reusable, durable, heat-pipe is employed to fabricate a hypersonic vehicle leading edge and nose cap.

Plasma Processing Systems for the Manufacture of Refractory Metals and their Alloys for Military Needs

DTIC Science & Technology

1978-10-09

melting point is around 4000*K. An exceedingly interesting feature of these solidification composites is the formation of fibrous MC type carbide ...the matrix could be refractory metal binary alloys with copper or uranium and the eutectic phase could be carbide of tungsten, * molybdenum, tantalum or...42 Accs -n or - *DTTI Tf Avn ! -7ll ’ i CrDi t , l’’*i,;. LIST OF FIGURES FIG. 1 Flow Diagram of Cemented Carbide Manufacture

Coated graphite articles useful in metallurgical processes and method for making same

DOEpatents

Holcombe, Cressie E.; Bird, Eugene L.

1995-01-01

Graphite articles including crucibles and molds used in metallurgical processes involving the melting and the handling of molten metals and alloys that are reactive with carbon when in a molten state and at process temperatures up to about 2000.degree. C. are provided with a multiple-layer coating for inhibiting carbon diffusion from the graphite into the molten metal or alloys. The coating is provided by a first coating increment of a carbide-forming metal on selected surfaces of the graphite, a second coating increment of a carbide forming metal and a refractory metal oxide, and a third coating increment of a refractory metal oxide. The second coating increment provides thermal shock absorbing characteristics to prevent delamination of the coating during temperature cycling. A wash coat of unstabilized zirconia or titanium nitride can be applied onto the third coating increment to facilitate release of melts from the coating.

High Temperature Stability of Dissimilar Metal Joints in Fission Surface Power Systems

NASA Technical Reports Server (NTRS)

Locci, Ivan E.; Nesbitt, James A.; Ritzert, Frank J.; Bowman, Cheryl L.

2007-01-01

Future generations of power systems for spacecraft and lunar surface systems will likely require a strong dependence on nuclear power. The design of a space nuclear power plant involves integrating together major subsystems with varying materia1 requirements. Refractory alloys are repeatedly considered for major structural components in space power reactor designs because refractory alloys retain their strength at higher temperatures than other classes of metals. The relatively higher mass and lower ductility of the refractory alloys make them less attractive for lower temperature subsystems in the power plant such as the power conversion system. The power conversion system would consist more likely of intermediate temperature Ni-based superalloys. One of many unanswered questions about the use of refractory alloys in a space power plant is how to transition from the use of the structural refractory alloy to more traditional structural alloys. Because deleterious phases can form when complex alloys are joined and operated at elevated temperatures, dissimilar material diffusion analyses of refractory alloys and superalloys are needed to inform designers about options of joint temperature and operational lifetime. Combinations of four superalloys and six refractory alloys were bonded and annealed at 1150 K and 1300 K to examine diffusional interactions in this study. Joints formed through hot pressing and hot isostatic pressing were compared. Results on newer alloys compared favorably to historical data. Diffusional stability is promising for some combinations of Mo-Re alloys and superalloys at 1150 K, but it appears that lower joint temperatures would be required for other refractory alloy couples.

Fixture for forming evaporative pattern (EPC) process patterns

DOEpatents

Turner, Paul C.; Jordan, Ronald R.; Hansen, Jeffrey S.

1993-01-01

A method of casting metal using evaporative pattern casting process patterns in combination with a fixture for creating and maintaining a desired configuration in flexible patterns. A pattern is constructed and gently bent to the curvature of a suitable fixture. String or thin wire, which burns off during casting, is used to tie the pattern to the fixture. The fixture with pattern is dipped in a commercially available refractory wash to prevent metal adherence and sticking to the fixture. When the refractory wash is dry, the fixture and pattern are placed in a flask, and sand is added and compacted by vibration. The pattern remains in position, restrained by the fixture. Metal that is poured directly into the pattern replaces the pattern exactly but does not contact or weld to the fixture due to the protective refractory layer. When solid, the casting is easily separated from the fixture. The fixture can be cleaned for reuse in conventional casting cleaning equipment.

A RELICT Spinel Grain in an Allende Ferromagnesian Chondrule

NASA Astrophysics Data System (ADS)

Misawa, K.; Fujita, T.; Kitamura, M.; Nakamura, N.; Yurimoto, H.

1993-07-01

It is suggested that one of the refractory lithophile precursors in CV-CO chondrules was a hightemperature condensate from the nebular gas and was related to Ca,Al-rich inclusions (CAIs) [1-3]. However, little is known about refractory siderophile precursors in chondrules [4]. Allende barred olivine chondrule R-11 consists mainly of olivine (Fa(sub)7- 18), pyroxene (En(sub)93Fs(sub)1Wo(sub)6, En(sub)66Fs(sub)1Wo(sub)33), plagioclase (An(sub)80), Fe-poor spinel, and alkali-rich glass. The CI- chondrite normalized REE pattern of the chondrule, excluding a spinel grain, are fractionated, HREEdepleted (4.6-7.8 x CI) with a large positive Yb anomaly. The REE abundances are hump-shaped functions of elemental volatility, moderately refractory REE-enriched, suggesting that the refractory lithophile precursor component of R-11 could be a condensate from the nebular gas and related to Group 11 CAIs [1,2]. An interior portion of spinel is almost Fe-free, but in an outer zone (2040 micrometers in width) FeO contents increase rapidly. TiO(sub)2, Cr(sub)2O(sub)3, and V(sub)2O(sub)3 contents in core spinel are less than 0.5%, which is different from the V-rich nature of spinel in fluffy Type A CAIs [5]. The Fe-Mg zoning of spinel may have been generated by diffusional emplacement of Mg and Fe during chondrule-forming events. The spinel contains silicate inclusions and tiny metallic grains. The largest silicate inclusion is composed of Al,Ti-rich pyroxene and Ak 40 melilite. One of the submicrometersized grains was analyzed by SEM-EDS and found to be composed of refractory Pt-group metals with minor amounts of Fe and Ni. This is the first occurrence of refractory Pt-group metal nuggets in a ferromagnesian chondrule from the Allende meteorite. Tungsten, Os, Ir, Mo, and Ru are enriched 2-6 x 10^5 relative to CIs, and abundances of Pt and Rh decrease 2-10 x 10^4 with increasing volatility. In addition, abundances of Fe and Ni in the nugget are equal to or less than that CI chondrites. A depletion of Mo relative to other refractory metals may have resulted from high- temperature oxidation [6]. Chondrule R-11 exhibits both similarities (spinel and plagioclase chemistry; Group II REE pattern) and differences (fassaite chemistry; existence of refractory Pt-group metal nuggets and melilite) with respect to POIs [3] carrying isotopically fractionated Mg. Refractory Pt-group metal nuggets in CAIs are considered to have been produced during high-temperature events (at least 1300 degrees C) before total condensation of Fe in the early solar nebula [8-10]. In analogy with the formation history with CAIs, we suggest that one of the refractory siderophile precursor components of Allende chondrules is a high-temperature condensate from the nebular gas and is associated with refractory oxide and silicates. References: [1] Misawa K. and Nakamura N. (1988) GCA, 52, 1669. [2] Misawa K. and Nakamura N. (1988) Nature, 334, 47. [3] Sheng Y. J. et al. (1991) GCA, 55, 581. [4] Grossman J. N. et al. (1988) In Meteorites and the Early Solar System (J. F. Kerridge and M. S. Matthews, eds.), 619, Univ. of Arizona. [5] MacPherson G. J. and Grossman L. (1984) GCA, 48, 29. [6] Fegley B. Jr. and Palme H. (1985) EPSL, 72, 311. [7] Wark D. A. and Lovering J. F. (1976) LS VII, 912. [8] Palme H. and Wlotzka F. (1976) EPSL, 33, 45. [9] El Goresy A. et al. (1978) Proc. LPSC 9th, 1279. [10] Blander M. and Fuchs L. H. (1980) Proc. LPSC 11th, 929.

Autologous Peripheral Blood Stem Cell Transplant Followed by Donor Bone Marrow Transplant in Treating Patients With High-Risk Hodgkin Lymphoma, Non-Hodgkin Lymphoma, Multiple Myeloma, or Chronic Lymphocytic Leukemia

ClinicalTrials.gov

2017-12-26

B-Cell Prolymphocytic Leukemia; Hypodiploidy; Loss of Chromosome 17p; Plasma Cell Leukemia; Progression of Multiple Myeloma or Plasma Cell Leukemia; Recurrent Adult Hodgkin Lymphoma; Recurrent Adult Non-Hodgkin Lymphoma; Recurrent Childhood Hodgkin Lymphoma; Recurrent Childhood Non-Hodgkin Lymphoma; Recurrent Chronic Lymphocytic Leukemia; Recurrent Plasma Cell Myeloma; Recurrent Small Lymphocytic Lymphoma; Refractory Childhood Hodgkin Lymphoma; Refractory Chronic Lymphocytic Leukemia; Refractory Non-Hodgkin Lymphoma; Refractory Plasma Cell Myeloma; Refractory Small Lymphocytic Lymphoma; t(14;16); t(4;14); T-Cell Prolymphocytic Leukemia; Waldenstrom Macroglobulinemia

Modelling Simulation and Comparison of Refractory Corrosion at RHI's Technology Center

NASA Astrophysics Data System (ADS)

Gregurek, Dean; Ressler, Angelika; Franzkowiak, Anna; Spanring, Alfred

In order to determine the most suitable refractory products and improve the lining lifetime for the diverse furnaces used in the nonferrous metal industry, corrosion tests are performed at RHF's Technology Center. The practical facilities include the cup test, induction furnace, rotary kiln, and drip slag test described in this paper, which enable a comprehensive understanding of the chemo-thermal brick wear on a pilot scale. The corrosion trials are performed with actual slags generated during operations at a customer's plant. To determine the highest influencing wear parameter, every single test is combined with a detailed mineralogical investigation and thermochemical calculations performed using FactSage. Based on the results, tailored refractory solutions for the nonferrous metal industry can be provided in combination with trials conducted at the customer's site.

Compatibility of Niobium Alloys and Superalloys in a Flowing He-Xe Power Conversion System

NASA Technical Reports Server (NTRS)

Bowman, Cheryl L.; Ritzert, Frank J.; Smialek, James L.; Jaster, Mark L.; rker, Samuel P.

2004-01-01

Proposed concepts for an ambitious mission to explore Jupiter's three icy moons place significant demands on the various spacecraft systems. There are many challenges related to the high output power conversion systems being considered, and one example is the need to ensure system compatibility at all levels. The utilization of appropriate materials for component structures is important to ensuring long mission life. Refractory metal alloys have attractive high-temperature properties in inert environments, but these alloys are sometimes susceptible to contamination. Potential material compatibility issues exist between refractory metal candidates and more conventional alloys. Nb-1Zr has long been considered one of the most well characterized refractory alloys that is well suited for elevated-temperature use and liquid-metal compatibility. However, previous studies have suggested that niobium alloys can not co-exist in a closed system with traditional stainless steels or superalloys due to transport of contaminants. The relevance of this information to a proposed power conversion system is discussed. Also, experiments and fundamental calculations are being performed to determine contamination transport from candidate superalloys to Nb-1Zr in a closed system with an inert carrier gas. Potential protective schemes are explored to ensure system level compatibility between the refractory alloy Nb-1Zr and a nickel-based superalloy.

High temperature glass coatings for superalloys and refractory metals

NASA Technical Reports Server (NTRS)

Chapman, J. W.; Grekila, R. B.; Hirayama, C.; Mattox, D. M.

1970-01-01

New glasses are used as protective coatings on metals and alloys susceptible to oxidation at high temperatures in oxidizing atmospheres. Glasses are stable and solid at temperatures up to 1000 deg C, adhere well to metal surfaces, and are usable for metals with broad range of expansion coefficients.

Advanced refractory-metal and process technology for the fabrication of x-ray masks

NASA Astrophysics Data System (ADS)

Brooks, Cameron J.; Racette, Kenneth C.; Lercel, Michael J.; Powers, Lynn A.; Benoit, Douglas E.

1999-06-01

This paper provides an in-depth report of the advanced materials and process technology being developed for x-ray mask manufacturing at IBM. Masks using diamond membranes as replacement for silicon carbide are currently being fabricated. Alternate tantalum-based absorbers, such as tantalum boron, which offer improved etch resolution and critical dimension control, as well as higher x-ray absorption, are also being investigated. In addition to the absorber studies, the development of conductive chromium- based hard-mask films to replace the current silicon oxynitride layer is being explored. The progress of this advanced-materials work, which includes significant enhancements to x-ray mask image-placement performance, will be outlined.

Effects of composition and testing conditions on oxidation behavior of four cast commercial nickel-base superalloys

NASA Technical Reports Server (NTRS)

Lowell, C. E.; Probst, H. B.

1974-01-01

Four cast nickel-base superalloys were oxidized at 1000 and 1100 C for times up to 100 hr in static air and a Mach 1 gas stream. The oxidation resistance was judged by weight change, metal thickness loss, depletion-zone formation, and oxide formation and morphology. The alloys which formed mostly nickel aluminate (NiAl2O4) and aluminum oxide (Al2O3) (B-1900, VIA, and to a lesser extent 713C) were more oxidation resistant. Poorer oxidation resistance was associated with the appearance of chromium sesquioxide (Cr2O3) and chromite spinel (738X). Refractory metal content had little effect on oxidation resistance. Refractory metals appeared in the scale as tapiolite (NiM2O6, where M represents the refractory metal). Thermal cycling in static air appeared to supply sufficient data for the evaluation of oxidation resistance, especially for alloys which form oxides of low volatility. For alloys of higher chromium levels with high propensities toward forming a chromium-bearing scale of higher volatility, testing under conditions of high gas velocity is necessary to assess fully the behavior of the alloy.

Split-course, high-dose palliative pelvic radiotherapy for locally progressive hormone-refractory prostate cancer.

PubMed

Gogna, Nirdosh Kumar; Baxi, Siddhartha; Hickey, Brigid; Baumann, Kathryn; Burmeister, Elizabeth; Holt, Tanya

2012-06-01

Local progression, in patients with hormone-refractory prostate cancer, often causes significant morbidity. Pelvic radiotherapy (RT) provides effective palliation in this setting, with most published studies supporting the use of high-dose regimens. The aim of the present study was to examine the role of split-course hypofractionated RT used at our institution in treating this group of patients. A total of 34 men with locoregionally progressive hormone-refractory prostate cancer, treated with a split course of pelvic RT (45-60 Gy in 18-24 fractions) between 2000 and 2008 were analyzed. The primary endpoints were the response rate and actuarial locoregional progression-free survival. Secondary endpoints included overall survival, compliance, and acute and late toxicity. The median age was 71 years (range, 53-88). Treatment resulted in an overall initial response rate of 91%, a median locoregional progression-free survival of 43 months, and median overall survival of 28 months. Compliance was excellent and no significant late toxicity was reported. The split course pelvic RT described has an acceptable toxicity profile, is effective, and compares well with other high-dose palliative regimens that have been previously reported. Copyright © 2012 Elsevier Inc. All rights reserved.

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

NASA Technical Reports Server (NTRS)

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.

Magnetohydrodynamic electrode

DOEpatents

Marchant, David D.; Killpatrick, Don H.

1978-01-01

An electrode capable of withstanding high temperatures and suitable for use as a current collector in the channel of a magnetohydrodynamic (MHD) generator consists of a sintered powdered metal base portion, the upper surface of the base being coated with a first layer of nickel aluminide, an intermediate layer of a mixture of nickel aluminide - refractory ceramic on the first layer and a third or outer layer of a refractory ceramic material on the intermediate layer. The sintered powdered metal base resists spalling by the ceramic coatings and permits greater electrode compliance to thermal shock. The density of the powdered metal base can be varied to allow optimization of the thermal conductivity of the electrode and prevent excess heat loss from the channel.

Chlorination processing of local planetary ores for oxygen and metallurgically important metals

NASA Technical Reports Server (NTRS)

Lynch, D. C.

1989-01-01

The use of chlorine to extract, reclaim, and purify metals has attractive possibilities for extraterrestrial processing of local planetary resources. While a complete cyclic process has been proposed for the recovery of metallurgically significant metals and oxygen, herein the chlorination step of the cycle is examined. An experimental apparatus for reacting refractory materials, such as ilmenite, in a microwave induced plasma is being built. Complex equilibria calculations reveal that stable refractory materials can, under the influence of a plasma, undergo chlorination and yield oxygen as a by-product. These issues and the potential advantages for plasma processing in space are reviewed. Also presented is a discussion of the complex equilibria program used in the analysis.

Materials interactions between the thermoelectric converter and the 5kwe reactor system

NASA Technical Reports Server (NTRS)

Ferry, P. B.

1973-01-01

The integration of a compact thermoelectric converter with a 5-kwe reactor system is described. Material interaction uncertainties study is also presented. This includes degradation of the required austenitic - refractory metal transition joint during operation at high temperatures; loss of corrosion resistance; embrittlement by the presence of hydrogen; and loss of design margin by transport of interstitial elements. Analysis and limited experimental evidence indicate that these potential materials interactions can be adequately controlled. Group 5-2 refractory metals can be utilized without unacceptable adverse effect on system reliability.

Method for producing refractory nitrides

DOEpatents

Quinby, Thomas C.

1989-01-24

A process for making fine, uniform metal nitride powders that can be hot pressed or sintered. A metal salt is placed in a solvent with Melamine and warmed until a metal-Melamine compound forms. The solution is cooled and the metal-Melamine precipitate is calcined at a temperature below 700.degree. C. to form the metal nitrides and to avoid formation of the metal oxide.

High temperature composites. Status and future directions

NASA Technical Reports Server (NTRS)

Signorelli, R. A.

1982-01-01

A summary of research investigations of manufacturing methods, fabrication methods, and testing of high temperature composites for use in gas turbine engines is presented. Ceramic/ceramic, ceramic/metal, and metal/metal composites are considered. Directional solidification of superalloys and eutectic alloys, fiber reinforced metal and ceramic composites, ceramic fibers and whiskers, refractory coatings, metal fiber/metal composites, matrix metal selection, and the preparation of test specimens are discussed.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schuett, K.J.; Pawlak, J.P.; Traina, L.

No. 13 Blast Furnace at US Steel`s Gary Works is a 35 tuyere furnace with a 36.5 ft. hearth capable of producing over 9,000 tons of hot metal per day. The current casthouse design was placed in service following the second reline in the fall of 1979. This design anticipated daily production rates averaging 7,500 tons of hot metal per day and provided for removable troughs at two of the three tapholes. At the time, the troughs were rammed with a high alumina/silicon carbide granular ramming material that provided the operators with trough campaign lives between 60,000--70,000 tons of hotmore » metal produced. As refractory technology progressed, low cement/low moisture castables were introduced to the trough systems on No. 13 Blast Furnace. The immediate success of the castables was tempered by emergence of a new unexpected problem. That problem was the thermal expansion of the castable. The paper describes the problems that resulted in the need to modify the trough design, the new design of the trough, and its improvement in iron trough campaign life and reliability.« less

Impact of prior treatment and depth of response on survival in MM-003, a randomized phase 3 study comparing pomalidomide plus low-dose dexamethasone versus high-dose dexamethasone in relapsed/refractory multiple myeloma

PubMed Central

San Miguel, Jesus F.; Weisel, Katja C.; Song, Kevin W.; Delforge, Michel; Karlin, Lionel; Goldschmidt, Hartmut; Moreau, Philippe; Banos, Anne; Oriol, Albert; Garderet, Laurent; Cavo, Michele; Ivanova, Valentina; Alegre, Adrian; Martinez-Lopez, Joaquin; Chen, Christine; Renner, Christoph; Bahlis, Nizar Jacques; Yu, Xin; Teasdale, Terri; Sternas, Lars; Jacques, Christian; Zaki, Mohamed H.; Dimopoulos, Meletios A.

2015-01-01

Pomalidomide is a distinct oral IMiD® immunomodulatory agent with direct antimyeloma, stromal-support inhibitory, and immunomodulatory effects. The pivotal, multicenter, open-label, randomized phase 3 trial MM-003 compared pomalidomide + low-dose dexamethasone vs high-dose dexamethasone in 455 patients with refractory or relapsed and refractory multiple myeloma after failure of bortezomib and lenalidomide treatment. Initial results demonstrated significantly longer progression-free survival and overall survival with an acceptable tolerability profile for pomalidomide + low-dose dexamethasone vs high-dose dexamethasone. This secondary analysis describes patient outcomes by treatment history and depth of response. Pomalidomide + low-dose dexamethasone significantly prolonged progression-free survival and favored overall survival vs high-dose dexamethasone for all subgroups analyzed, regardless of prior treatments or refractory status. Both univariate and multivariate analyses showed that no variable relating to either the number (≤ or > 3) or type of prior treatment was a significant predictor of progression-free survival or overall survival. No cross-resistance with prior lenalidomide or thalidomide treatment was observed. Patients achieving a minimal response or better to pomalidomide + low-dose dexamethasone treatment experienced a survival benefit, which was even higher in those achieving at least a partial response (17.2 and 19.9 months, respectively, as compared with 7.5 months for patients with less than minimal response). These data suggest that pomalidomide + low-dose dexamethasone should be considered a standard of care in patients with refractory or relapsed and refractory multiple myeloma regardless of prior treatment. ClinicalTrials.gov: NCT01311687; EudraCT: 2010-019820-30. PMID:26160879

Electrochemical cell with powdered electrically insulative material as a separator

DOEpatents

Mathers, James P.; Olszanski, Theodore W.; Boquist, Carl W.

1978-01-01

A secondary electrochemical cell includes electrodes separated by a layer of electrically insulative powder. The powder includes refractory materials selected from the oxides and nitrides of metals and metaloids. The powdered refractory material, blended with electrolyte particles, can be compacted in layers with electrode materials to form an integral electrode structure or separately assembled into the cell. The assembled cell is heated to operating temperature leaving porous layers of electrically insulative, refractory particles, containing molten electrolyte between the electrodes.

Method of preparing a powdered, electrically insulative separator for use in an electrochemical cell

DOEpatents

Cooper, Tom O.; Miller, William E.

1978-01-01

A secondary electrochemical cell includes electrodes separated by a layer of electrically insulative powder. The powder includes refractory materials selected from the oxides and nitrides of metals and metaloids. The powdered refractory material, blended with electrolyte particles, is compacted as layers onto an electrode to form an integral electrode structure and assembled into the cell. The assembled cell is heated to its operating temperature leaving porous layers of electrically insulative, refractory particles, containing molten electrolyte between the electrodes.

HIGH TEMPERATURE REFRACTORY COATING FOR GRAPHITE MOLDS

DOEpatents

Stoddard, S.D.

1958-10-21

An improved foundry mold coating for use with graphite molds used in the casting of uranium is presented. The refractory mold coating serves to keep the molten uranium from contact with graphite of the mold and thus prevents carbon pickup by the molten metal. The refractory coating is made by dry mixing certain specific amounts of aluminum oxide, bentonite, Tennessee ball clay, and a soluble silicate salt. Water is then added to the mixture and the suspension thus formed is applied by spraying onto the mold.

Improved Rare-Earth Emitter Hollow Cathode

NASA Technical Reports Server (NTRS)

Goebel, Dan M.

2011-01-01

An improvement has been made to the design of the hollow cathode geometry that was created for the rare-earth electron emitter described in Compact Rare Earth Emitter Hollow Cathode (NPO-44923), NASA Tech Briefs, Vol. 34, No. 3 (March 2010), p. 52. The original interior assembly was made entirely of graphite in order to be compatible with the LaB6 material, which cannot be touched by metals during operation due to boron diffusion causing embrittlement issues in high-temperature refractory materials. Also, the graphite tube was difficult to machine and was subject to vibration-induced fracturing. This innovation replaces the graphite tube with one made out of refractory metal that is relatively easy to manufacture. The cathode support tube is made of molybdenum or molybdenum-rhenium. This material is easily gun-bored to near the tolerances required, and finish machined with steps at each end that capture the orifice plate and the mounting flange. This provides the manufacturability and robustness needed for flight applications, and eliminates the need for expensive e-beam welding used in prior cathodes. The LaB6 insert is protected from direct contact with the refractory metal tube by thin, graphite sleeves in a cup-arrangement around the ends of the insert. The sleeves, insert, and orifice plate are held in place by a ceramic spacer and tungsten spring inserted inside the tube. To heat the cathode, an insulating tube is slipped around the refractory metal hollow tube, which can be made of high-temperature materials like boron nitride or aluminum nitride. A screw-shaped slot, or series of slots, is machined in the outside of the ceramic tube to constrain a refractory metal wire wound inside the slot that is used as the heater. The screw slot can hold a single heater wire that is then connected to the front of the cathode tube by tack-welding to complete the electrical circuit, or it can be a double slot that takes a bifilar wound heater with both leads coming out the back. This configuration replaces the previous sheathed heater design that limited the cycling-life of the cathode.

Clinicopathological features and outcomes of progression of CLL on the BCL2 inhibitor venetoclax.

PubMed

Anderson, Mary Ann; Tam, Constantine; Lew, Thomas E; Juneja, Surender; Juneja, Manu; Westerman, David; Wall, Meaghan; Lade, Stephen; Gorelik, Alexandra; Huang, David C S; Seymour, John F; Roberts, Andrew W

2017-06-22

The BCL2 inhibitor venetoclax achieves responses in ∼79% of patients with relapsed or refractory chronic lymphocytic leukemia/small lymphocytic lymphoma (RR-CLL/SLL), irrespective of risk factors associated with poor response to chemoimmunotherapy. A limitation of this targeted therapy is progressive disease (PD) in some patients. To define the risk factors for progression, the clinicopathological features of PD, and the outcomes for patients after venetoclax failure, we analyzed 67 heavily pretreated patients on 3 early phase clinical trials. Investigations at progression included positron emission tomography scan and biopsy. Twenty-five (37%) patients manifested PD on therapy: 17 with Richter transformation (RT) and 8 with progressive CLL/SLL. RT occurred significantly earlier (median 7.9 months) than progressive CLL (median 23.4 months) ( P = .003). Among patients who received the recommended phase 2 dose of venetoclax or higher (≥400 mg/d), fludarabine refractoriness and complex karyotype were associated with progression (hazard ratio 7.01 [95% confidence interval 1.7-28.5]; P = .002 and 6.6 [1.5-29.8]; P = .005, respectively), whereas del(17p) and/or TP53 mutation were not ( P = .75). Median postprogression survival was 13 (<1-49.9) months. Bruton tyrosine kinase inhibitors were active in progressive CLL, but outcomes were mixed. Patients with disease that is fludarabine refractory or who have complex cytogenetics should have occult RT excluded before initiating venetoclax therapy. © 2017 by The American Society of Hematology.

Coal-fired high performance power generating system. Quarterly progress report, October 1, 1994--December 31, 1994

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1995-08-01

This report covers work carried out under Task 3, Preliminary R and D, under contract DE-AC22-92PC91155, {open_quotes}Engineering Development of a Coal-Fired High Performance Power Generation System{close_quotes} between DOE Pittsburgh Energy Technology Center and United Technologies Research Center. The goals of the program are to develop a coal-fired high performance power generation system (HIPPS) by the year 2000 that is capable of (1) > 47% thermal efficiency; (2) NO{sub x}, SO{sub x} and particulates {<=}25% NSPS; (3) cost {>=}65% of heat input; (4) all solid wastes benign. In our design consideration, we have tried to render all waste streams benign andmore » if possible convert them to a commercial product. It appears that vitrified slag has commercial values. If the flyash is reinjected through the furnace, along with the dry bottom ash, then the amount of the less valuable solid waste stream (ash) can be minimized. A limitation on this procedure arises if it results in the buildup of toxic metal concentrations in either the slag, the flyash or other APCD components. We have assembled analytical tools to describe the progress of specific toxic metals in our system. The outline of the analytical procedure is presented in the first section of this report. The strengths and corrosion resistance of five candidate refractories have been studied in this quarter. Some of the results are presented and compared for selected preparation conditions (mixing, drying time and drying temperatures). A 100 hour pilot-scale stagging combustor test of the prototype radiant panel is being planned. Several potential refractory brick materials are under review and five will be selected for the first 100 hour test. The design of the prototype panel is presented along with some of the test requirements.« less

Theoretical and Experimental Investigations on the Mechanism of Carbothermal Reduction of Zirconia (Preprint)

DTIC Science & Technology

2012-08-01

Properties. Abyss Books, Washington, D.C., 2002. 2. G. Montel, A. Lebugle and H. Pastor. "Manufacture of Materials Containing Refractory Borides ...and ZrO2," International Journal of Refractory Metals and Hard Materials, 17, 235-43 (1999). 10. A.W. Weimer, Carbide, nitride and boride

Estimation of sensing characteristics for refractory nitrides based gain assisted core-shell plasmonic nanoparticles

NASA Astrophysics Data System (ADS)

Shishodia, Manmohan Singh; Pathania, Pankaj

2018-04-01

Refractory transition metal nitrides such as zirconium nitride (ZrN), hafnium nitride (HfN) and titanium nitride (TiN) have emerged as viable alternatives to coinage metals based plasmonic materials, e.g., gold (Au) and silver (Ag). The present work assesses the suitability of gain assisted ZrN-, HfN- and TiN-based conventional core-shell nanoparticles (CCSNPs) and multilayered core-shell nanoparticles (MCSNPs) for refractive index sensing. We report that the optical gain incorporation in the dielectric layer leads to multifold enhancement of the scattering efficiency (Qsca), substantial reduction of the spectral full width at half maximum, and a higher figure of merit (FOM). In comparison with CCSNPs, the MCSNP system exhibits superior sensing characteristics such as higher FOM, ˜ 45% reduction in the critical optical gain, response shift towards the biological window, and higher degree of tunability. Inherent biocompatibility, growth compatibility, chemical stability and flexible spectral tuning of refractory nitrides augmented by superior sensing properties in the present work may pave the way for refractory nitrides based low cost sensing.

Comprehensive Utilization of Iron and Phosphorus from High-Phosphorus Refractory Iron Ore

NASA Astrophysics Data System (ADS)

Sun, Yongsheng; Zhang, Qi; Han, Yuexin; Gao, Peng; Li, Guofeng

2018-02-01

An innovative process of coal-based reduction followed by magnetic separation and dephosphorization was developed to simultaneously recover iron and phosphorus from one typical high-phosphorus refractory iron ore. The experimental results showed that the iron minerals in iron ore were reduced to metallic iron during the coal-based reduction and the phosphorus was enriched in the metallic iron phase. The CaO-SiO2-FeO-Al2O3 slag system was used in the dephosphorization of metallic iron. A hot metal of 99.17% Fe and 0.10% P was produced with Fe recovery of 84.41%. Meanwhile, a dephosphorization slag of 5.72% P was obtained with P recovery of 67.23%. The contents of impurities in hot metal were very low, and it could be used as feedstock for steelmaking after a secondary refining. Phosphorus in the dephosphorization slag mainly existed in the form of a 5CaO·P2O5·SiO2 solid solution where the P2O5 content is 13.10%. At a slag particle size of 20.7 μm (90% passing), 94.54% of the P2O5 could be solubilized in citric acid, indicating the slag met the feedstock requirements in phosphate fertilizer production. Consequently, the proposed process achieved simultaneous Fe and P recovery, paving the way to comprehensive utilization of high-phosphorus refractory iron ore.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Selle, J E

Attempts were made to apply the Kaufman method of calculating binary phase diagrams to the calculation of binary phase diagrams between the rare earths, actinides, and the refractory transition metals. Difficulties were encountered in applying the method to the rare earths and actinides, and modifications were necessary to provide accurate representation of known diagrams. To calculate the interaction parameters for rare earth-rare earth diagrams, it was necessary to use the atomic volumes for each of the phases: liquid, body-centered cubic, hexagonal close-packed, and face-centered cubic. Determination of the atomic volumes of each of these phases for each element is discussedmore » in detail. In some cases, empirical means were necessary. Results are presented on the calculation of rare earth-rare earth, rare earth-actinide, and actinide-actinide diagrams. For rare earth-refractory transition metal diagrams and actinide-refractory transition metal diagrams, empirical means were required to develop values for the enthalpy of vaporization for rare earth elements and values for the constant (C) required when intermediate phases are present. Results of using the values determined for each element are presented.« less

Rare-earth metals in nickel aluminide-based alloys: III. Structure and properties of multicomponent Ni3Al-based alloys

NASA Astrophysics Data System (ADS)

Bazyleva, O. A.; Povarova, K. B.; Kazanskaya, N. K.; Drozdov, A. A.

2009-04-01

The possibility of increasing the life of heterophase cast light Ni3Al-based superalloys at temperatures higher than 0.8 T m of Ni3Al is studied when their directional structure is additionally stabilized by nanoprecipitates, which form upon additional alloying of these alloys by refractory and active metals, and using special methods for preparing and melting of an alloy charge. The effect of the method of introducing the main components and refractory reaction-active and surface-active alloying elements into Ni3Al-based cast superalloys, which are thermally stable natural composite materials of the eutectic type, on the structure-phase state and the life of these alloys is studied. When these alloys are melted, it is necessary to perform a set of measures to form particles of refractory oxide cores covered with the β-NiAl phase and, then, γ'prim-Ni3Al phase precipitates during solidification. The latter phase forms the outer shell of grain nuclei, which provides high thermal stability and hot strength of an intermetallic compound-based alloy. As a result, a modified structure that is stabilized by the nanoprecipitates of nickel and aluminum lanthanides and the nanoprecipitates of phases containing refractory metals is formed. This structure enhances the life of the alloy at 1000 °C by a factor of 1.8-2.5.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Deng, Huixu; Li, Zhigang; Stan, Liliana

Broadband perfect absorber based on one ultrathin layer of the refractory metal chromium without structure pat- terning is proposed and demonstrated. The ideal permittivity of the metal layer for achieving broadband perfect absorption is derived based on the impedance transformation method. Since the permittivity of the refractory metal chromium matches this ideal permittivity well in the visible and near-infrared range, a silica-chromium-silica three-layer absorber is fabricated to demonstrate the broadband perfect absorption. The experimental results under normal incidence show that the absorption is above 90% over the wavelength range of 0.4–1.4 μm, and the measurements under angled incidence within 400–800more » nm prove that the absorber is angle-insensitive and polarization- independent.« less

An Assessment of Recycled Refractory Material Performance After Two Years of Service in a Carbon Bake Furnace

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schubert, N.; Bennett, J.P.; Kwong, K.S.

1999-10-27

Material removed from carbon bake furnaces used to manufacture anodes for the production of aluminum metal has historically been disposed by landfill. This material is composed primarily of 50% alumina refractory. in 1997, Alcoa completed a highly successful program to reuse the spent refractories in castables for carbon bake furnace headwalls and flooring, as roadbed aggregate, and in other internal applications. This program recycled/reused 11,000 metric tons of used refractory material (99% of the material removed from the carbon bake furnace) and saved Alcoa over 3.8 of the 9.6 million dollar projected furnace rebuild costs. As assessment is made ofmore » the performance of the recycled refractory components after two years of service.« less

Retrospective analysis of an oral combination of dexamethasone, uracil plus tegafur and cyclophosphamide for hormone-refractory prostate cancer.

PubMed

Hatano, Koji; Nonomura, Norio; Nishimura, Kazuo; Kawashima, Atsunari; Mukai, Masatoshi; Nagahara, Akira; Nakai, Yasutomo; Nakayama, Masashi; Takayama, Hitoshi; Tsujimura, Akira; Okuyama, Akihiko

2011-02-01

To evaluate the clinical utility of an oral combination of dexamethasone, uracil plus tegafur and cyclophosphamide as a treatment for patients with hormone-refractory prostate cancer. Fifty-seven patients with hormone-refractory prostate cancer were treated with an oral administration of dexamethasone (1.0 mg/day), uracil plus tegafur (400 mg/day) and cyclophosphamide (100 mg/day). The median patient age was 71 years. Sixteen patients had symptomatic bone metastasis, 31 had asymptomatic bone metastasis and 8 showed lymph node metastasis. Eight patients presented with only biochemical progression as evaluated by serum prostate-specific antigen levels. Thirty-six (63%) of 57 patients demonstrated a ≥50% decline in serum prostate-specific antigen levels. The median time to prostate-specific antigen progression was 7.2 months. In patients with a prostate-specific antigen decline of ≥50%, the median time to progression was 13.3 months. With respect to pre-treatment markers, the duration of response to initial hormonal treatment was associated with the time to prostate-specific antigen progression. In 11 of 16 (69%) patients who complained of bone pain, the pain improved and became stable in 5 of those patients (31%). Most adverse events were mild and only three (5%) patients showed neutropenia of Grade 3 or higher. The combination of dexamethasone, uracil plus tegafur and cyclophosphamide is an effective and well tolerated regimen for hormone-refractory prostate cancer. To evaluate the survival benefits, further randomized studies are required.

Dietary prevention of hormone refractory prostate cancer in Lobund-Wistar rats: a review of studies in a relevant animal model.

PubMed

Pollard, Morris; Suckow, Mark A

2006-12-01

Lobund-Wistar (LW) rats, which have high testosterone levels, are predisposed to develop hormone-refractory prostate cancer (HRPC) spontaneously and by methylnitrosourea (MNU) induction, and the development of HRPC progresses through 2 stages. This paper reviews several studies in which LW rats were placed on soy-containing diets and were evaluated for development of either spontaneous or MNU-induced prostate cancer. The premalignant, testosterone-dependent stage is inhibited by testosterone deprivation. In the absence of testosterone deprivation, tumorigenesis progresses spontaneously to the testosterone-independent refractory stage. In LW rats: moderate caloric restriction prevented development of spontaneous prostate cancer; dietary 4-hydroxyphenylretinamide prevented MNU-induced prostate cancer; and dietary supplementation with soy protein isolate with high isoflavones prevented spontaneous and induced tumors and led to moderate reduction of serum testosterone. In rats 12 mo of age and younger, changing from the control diet to the soy+isoflavone diet significantly prevented progression of spontaneous tumors to the refractory stage of disease. Tumors that developed spontaneously and after MNU induction showed similar developmental stages and morphology, but MNU-induced tumors had shorter latency periods before development. The accumulated data indicate that soy-based diets are effective in the prevention of prostate cancer.

Crack-Free, Nondistorting Can For Hot Isostatic Pressing

NASA Technical Reports Server (NTRS)

Juhas, John J.

1991-01-01

New method of canning specimens made of composites of arc-sprayed and plasma-sprayed tape reduces outgassing and warping during hot isostatic pressing. Produces can having reliable, crack-free seal and thereby helps to ensure pressed product of high quality. Specimen placed in ring of refractory metal between two face sheets, also of refractory metal. Assembly placed in die in vacuum hot press, where simultaneously heated and pressed until plates become diffusion-welded to ring, forming sealed can around specimen. Specimen becomes partially densified, and fits snugly within can. Ready for further densification by hot isostatic pressing.

Advanced refractory metals and composites for extraterrestrial power systems

NASA Technical Reports Server (NTRS)

Titran, R. H.; Grobstein, Toni L.

1990-01-01

Concepts for future space power systems include nuclear and focused solar heat sources coupled to static and dynamic power-conversion devices; such systems must be designed for service lives as long as 30 years, despite service temperatures of the order of 1600 K. Materials are a critical technology-development factor in such aspects of these systems as reactor fuel containment, environmental protection, power management, and thermal management. Attention is given to the prospective performance of such refractory metals as Nb, W, and Mo alloys, W fiber-reinforced Nb-matrix composites, and HfC precipitate-strengthened W-Re alloys.

Development of wire drawing processes for refractory metal fibers

NASA Technical Reports Server (NTRS)

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.

Fabrication of large tungsten structures by chemical vapor deposition

NASA Technical Reports Server (NTRS)

Kahle, V. E.; Lewis, W. J.; Stubbs, V. R.

1971-01-01

Process is accomplished by reducing tungsten hexafluoride with hydrogen. Metallic tungsten of essentially 100 percent purity and density is produced and built up as dense deposit on heated mandrel assembly. Process variations are building up, sealing or bonding refractory metals at temperatures below transition temperatures of base metal substrates.

Experimental constraints on heating and cooling rates of refractory inclusions in the early solar system

NASA Technical Reports Server (NTRS)

Boynton, W. V.; DRAKE; HILDEBRAND; JONES; LEWIS; TREIMAN; WARK

1987-01-01

The refractory inclusions in carbonaceous chondrites were the subject of considerable interest since their discovery. These inclusions contain minerals that are predicted to be some of the earliest condensates from the solar nebula, and contain a plethora of isotopic anomalies of unknown origin. Of particular interest are those coarse-grained inclusions that contain refractory metal particles (Fe, Ni, Pt, Ru, Os Ir). Experimental studies of these inclusions in terrestrial laboratories are, however, complicated because the dense particles tend to settle out of a molten or partially molten silicate material. Heating experiments in the Space Station technology and microgravity in order to observe the effects of metal nuggets (which may act as heterogeneous nucleation sites) on nucleation rates in silicate systems and to measure simultaneously the relative volatilization rate of siderophile and lithophile species. Neither experiment is possible in the terrestrial environment.

Biodegradable stents for the treatment of refractory or recurrent benign esophageal stenosis.

PubMed

Imaz-Iglesia, Iñaki; García-Pérez, Sonia; Nachtnebel, Anna; Martín-Águeda, Belén; Sánchez-Piedra, Carlos; Karadayi, Bilgehan; Demirbaş, Ali Rıza

2016-06-01

Esophageal stents are used for the treatment of refractory and recurrent dyphagias. In 2007, esophageal biodegradable stents (EBS) were authorised as an alternative to existing metal and plastic stents in Europe. The advantages claimed for EBS are fewer complications concerning tissue ingrowth, stent migration and stent removal. We performed a systematic review to evaluate the efficacy and safety of EBS compared to fully-covered self-expanding metal stents, self-expanding plastic stents, and esophageal dilation for the treatment of refractory or recurrent benign esophageal stenosis. Three comparative studies (one randomized controlled trial and two cohort studies) were assessed. The studies used different inclusion criteria, had a very small (sample) size and the quality of the evidence was very low. Expert commentary: The current evidence is insufficient to determine the relative efficacy or safety of esophageal biodegradable stents. The results of this systematic review should be updated once new evidence is available.

A simple approach to estimate daily loads of total, refractory, and labile organic carbon from their seasonal loads in a watershed

Treesearch

Ying Ouyang; Johnny M. Grace; Wayne C. Zipperer; Jeff Hatten; Janet Dewey

2018-01-01

Loads of naturally occurring total organic carbons (TOC), refractory organic carbon (ROC), and labile organic carbon (LOC) instreams control the availability of nutrients and the solubility and toxicity of contaminants and affect biological activities throughabsorption of light and complex metals with production of carcinogenic compounds....

Carbide and carbonitride surface treatment method for refractory metals

DOEpatents

Meyer, G.A.; Schildbach, M.A.

1996-12-03

A carbide and carbonitride surface treatment method for refractory metals is provided, in steps including, heating a part formed of boron, chromium, hafnium, molybdenum, niobium, tantalum, titanium, tungsten or zirconium, or alloys thereof, in an evacuated chamber and then introducing reaction gases including nitrogen and hydrogen, either in elemental or water vapor form, which react with a source of elemental carbon to form carbon-containing gaseous reactants which then react with the metal part to form the desired surface layer. Apparatus for practicing the method is also provided, in the form of a carbide and carbonitride surface treatment system including a reaction chamber, a source of elemental carbon, a heating subassembly and a source of reaction gases. Alternative methods of providing the elemental carbon and the reaction gases are provided, as well as methods of supporting the metal part, evacuating the chamber with a vacuum subassembly and heating all of the components to the desired temperature. 5 figs.

Metal-silicate partitioning and the light element in the core (Invited)

NASA Astrophysics Data System (ADS)

Wood, B. J.; Wade, J.; Tuff, J.

2009-12-01

Most attempts to constrain the concentrations of “light” elements in the Earth’s core rely either on cosmochemical arguments or on arguments based on the densities and equations of state of Fe-alloys containing the element of concern. Despite its utility, the latter approach yields a wide range of permissible compositions and hence weak constraints. The major problem with the cosmochemical approach is that the abundances in the bulk Earth of all the candidate “light” elements- H, C, O, Si and S are highly uncertain because of their volatile behavior during planetary accretion. In contrast, refractory elements appear to be in approximately CI chondritic relative abundances in the Earth. This leads to the potential for using the partitioning of refractory siderophile elements between the mantle and core to constrain the concentrations of light elements in the core. Recent experimental metal-silicate partitioning data, coupled with mantle abundances of refractory siderophile elements (e.g. Wade and Wood, EPSL v.236, 78—95,2005; Kegler et. al. EPSL v.268, 28-40,2008) have shown that the core segregated from the mantle under high pressure conditions (~40 GPa). If a wide range of elements, from very siderophile, (e.g. Mo) through moderately (Ni, Co, W) to weakly siderophile (V, Cr, Nb, Si) are considered, the Earth also appears to have become more oxidized during accretion. Metal-silicate partitioning of some elements is also sensitive to the light element content of the metal. For example, Nb and W partitioning depend strongly on carbon, Mo on silicon and Cr on sulfur. Given the measured mantle abundances of the refractory elements, these observations enable the Si and C contents of the core to be constrained at ~5% and <2% respectively while partitioning is consistent with a cosmochemically-estimated S content of ~2%.

Catalytic conversion of light alkanes, Phase 3. Topical report, January 1990--December 1992

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

The mission of this work is to devise a new catalyst which can be used in the first simple, economic process to convert the light alkanes in natural gas to an alcohol-rich oxygenated product which can either be used as an environmentally friendly, high-performance liquid fuel, or a precursor to a liquid hydrocarbon transportation fuel. The authors have entered the proof-of-concept stage for converting isobutane to tert butyl alcohol in a practical process and are preparing to enter proof-of-concept of a propane to isopropyl alcohol process in the near future. Methane and ethane are more refractory and thus more difficultmore » to oxidize than the C{sub 3} and C{sub 4} hydrocarbons. Nonetheless, advances made in this area indicate that further research progress could achieve the goal of their direct conversion to alcohols. Progress in Phase 3 catalytic vapor phase methane and ethane oxidation over metals in regular oxidic lattices are the subject of this topical report.« less

Titanium Combustion in Turbine Engines

DTIC Science & Technology

1979-07-01

metal fires . Due to the refractory nature of metal oxides, mcst of the heat of reac- tion will reside in the enthalpy of the products. In a surface...more closely approx- imates the conditions prevailing in large-scale accidental metal fires . The objectives of this research have been to better define...conditions on the propagating molten mass of burning metal. Metal fires involve propagating combus- tion, and the propagation of burning-must be

Fully covered self-expanding metallic stent placement for benign refractory esophageal strictures.

PubMed

Kahalekar, Vinit; Gupta, Deepak Trilokinath; Bhatt, Pratin; Shukla, Akash; Bhatia, Shobna

2017-05-01

Treatment options for benign refractory esophageal stricture are limited. We retrospectively analyzed data of 11 patients who underwent fully covered self-expanding metallic stent (FC-SEMS) placement for refractory benign esophageal stricture at our institute. Refractory benign esophageal stricture was defined as inability to dilate a stricture to a diameter of 14 mm after a minimum of five sessions at 2-week intervals or inability to maintain diameter of 14 mm for at least 4 weeks. Eleven patients with refractory benign esophageal stricture (corrosive-6, peptic-3, and post-sclerotherapy-2) underwent FC-SEMS placement. The stent was removed after 4-6 weeks as per manufacturer's recommendation. Patients were followed up for 1 year. Three patients with peptic strictures [length of stricture 2, 3, and 3 cm] and two patients with post-sclerotherapy stricture [length 2 and 1.5 cm] had complete response. Two of 6 patients with corrosive stricture (10 cm, 12 cm) developed recurrence of symptoms within 1 month of stent removal, and two after 2 months (8 cm, 3 cm). One patient with corrosive stricture (6 cm) had recurrence after 6 months, and responded to single session of dilatation. One patient with corrosive stricture was asymptomatic for last 12 months. Four stents were migrated. Four patients developed severe retrosternal pain following stent placement, which was managed with analgesics. There were no serious adverse events after placement of stent and removal of stent. Fully covered SEMS is safe and effective for refractory benign non-corrosive esophageal strictures.

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

NASA Technical Reports Server (NTRS)

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.;

Aluminum reduction cell electrode

DOEpatents

Payne, J.R.

1983-09-20

The invention is directed to an anode-cathode structure for an electrolytic cell for the reduction of alumina wherein the structure is comprised of a carbon anode assembly which straddles a wedge-shaped refractory hard metal cathode assembly having steeply sloped cathodic surfaces, each cathodic surface being paired in essentially parallel planar relationship with an anode surface. The anode-cathode structure not only takes into account the structural weakness of refractory hard metal materials but also permits the changing of the RHM assembly during operation of the cell. Further, the anode-cathode structure enhances the removal of anode gas from the interpolar gap between the anode and cathode surfaces. 10 figs.

Aluminum reduction cell electrode

DOEpatents

Payne, John R.

1983-09-20

The invention is directed to an anode-cathode structure for an electrolytic cell for the reduction of alumina wherein the structure is comprised of a carbon anode assembly which straddles a wedge-shaped refractory hard metal cathode assembly having steeply sloped cathodic surfaces, each cathodic surface being paired in essentially parallel planar relationship with an anode surface. The anode-cathode structure not only takes into account the structural weakness of refractory hard metal materials but also permits the changing of the RHM assembly during operation of the cell. Further, the anode-cathode structure enhances the removal of anode gas from the interpolar gap between the anode and cathode surfaces.

Miniature modified Faraday cup for micro electron beams

DOEpatents

Teruya, Alan T.; Elmer, John W.; Palmer, Todd A.; Walton, Chris C.

2008-05-27

A micro beam Faraday cup assembly includes a refractory metal layer with an odd number of thin, radially positioned traces in this refractory metal layer. Some of the radially positioned traces are located at the edge of the micro modified Faraday cup body and some of the radially positioned traces are located in the central portion of the micro modified Faraday cup body. Each set of traces is connected to a separate data acquisition channel to form multiple independent diagnostic networks. The data obtained from the two diagnostic networks are combined and inputted into a computed tomography algorithm to reconstruct the beam shape, size, and power density distribution.

Use of the peroxisome proliferator-activated receptor (PPAR) gamma ligand troglitazone as treatment for refractory breast cancer: a phase II study.

PubMed

Burstein, Harold J; Demetri, George D; Mueller, Elisabetta; Sarraf, Pasha; Spiegelman, Bruce M; Winer, Eric P

2003-06-01

To evaluate the therapeutic effects of the peroxisome proliferator-activated receptor (PPAR) gamma activating ligand, troglitazone, in patients with refractory metastatic breast cancer. Patients with advanced breast cancer refractory to at least one chemotherapy regimen (ER negative tumors) or two hormonal regimens (ER positive tumors) were treated with troglitazone at 800 mg p.o. QD until disease progression, to determine the percentage of patients free of progression at 6 months. Tumor response, toxicity, and changes in serum tumor markers (CEA, CA27.29) that might reflect alteration in tumor differentiation, were also examined. Twenty-two patients were enrolled before suspension of protocol accrual and treatment when troglitazone was withdrawn from commercial availability following FDA warnings on hepatic toxicity. No objective responses (CR or PR) were observed; only three patients had SD at 8 weeks. Patients came off study for PD (16), DLT (1), FDA withdrawal (2), or other (3) reasons. No patients took troglitazone for more than 20 weeks; all had experienced disease progression or began other systemic therapy within 6 months. All patients with elevated serum tumor markers (CEA and CA27.29) at baseline had rising tumor markers within 8 weeks. While clinical trials among different patient populations might uncover subtle effects on tumor differentiation, PPARgamma activation by troglitazone has little apparent clinical value among patients with treatment-refractory metastatic breast cancer.

Epirubicin, Cisplatin, and Capecitabine for Primary Platinum-Resistant or Platinum-Refractory Epithelial Ovarian Cancer

PubMed Central

Sayal, Karen; Gounaris, Ioannis; Basu, Bristi; Freeman, Sue; Moyle, Penny; Hosking, Karen; Iddawela, Mahesh; Jimenez-Linan, Mercedes; Abraham, Jean; Brenton, James; Hatcher, Helen; Earl, Helena; Parkinson, Christine

2015-01-01

Objective Primary platinum-resistant epithelial ovarian cancer (EOC) is an area of unmet medical need. There is limited evidence from small studies that platinum-based combinations can overcome “resistance” in a proportion of patients. We investigated the efficacy and toxicity of platinum-based combination chemotherapy in the platinum-resistant and platinum-refractory setting. Methods Epirubicin, cisplatin, and capecitabine (ECX) combination chemotherapy was used at our institution for the treatment of relapsed EOC. From the institutional database, we identified all patients with primary platinum-refractory or platinum-resistant relapse treated with ECX as second-line therapy between 2001 and 2012. We extracted demographic, clinical, treatment, and toxicity data and outcomes. We used logistic and Cox regression models to identify predictors of response and survival respectively. Results Thirty-four 34 patients (8 refractory, 26 resistant) were treated with ECX. Response Evaluation Criteria In Solid Tumors (RECIST) response rate was 45%, median progression-free survival (PFS) was 6.4 months, and overall survival (OS) was 10.6 months. Platinum-resistant patients had better outcomes than did platinum-refractory patients (response rate, 54% vs 0%, P = 0.047; PFS 7.2 vs 1.8 months, P < 0.0001; OS 14.4 vs 3 months, P < 0.001). In regression models, time to progression after first-line treatment and platinum-refractory status were the strongest predictors of response and PFS or OS, respectively. Patients with time to progression after first-line treatment longer than 3 months showed PFS and OS of 7.9 and 14.7 months, respectively. Toxicity was manageable, with only 13% of cycles administered at reduced doses. Conclusions Epirubicin, cisplatin, and capecitabine seems to be active in platinum-resistant relapsed EOC with manageable toxicity. Further prospective investigation of platinum-anthracycline combinations is warranted in patients who relapse 3 to 6 months after first-line platinum-taxane treatment. PMID:25962114

Nuclear reactor I

DOEpatents

Ference, Edward W.; Houtman, John L.; Waldby, Robert N.

1977-01-01

A nuclear reactor, particularly a liquid-metal breeder reactor whose upper internals include provision for channeling the liquid metal flowing from the core-component assemblies to the outlet plenum in vertical paths in direction generally along the direction of the respective assemblies. The metal is channeled by chimneys, each secured to, and extending from, a grid through whose openings the metal emitted by a plurality of core-component assemblies encompassed by the grid flows. To reduce the stresses resulting from structural interaction, or the transmissive of thermal strains due to large temperature differences in the liquid metal emitted from neighboring core-component assemblies, throughout the chimneys and the other components of the upper internals, the grids and the chimneys are supported from the heat plate and the core barrel by support columns (double portal support) which are secured to the head plate at the top and to a member, which supports the grids and is keyed to the core barrel, at the bottom. In addition to being restrained from lateral flow by the chimneys, the liquid metal is also restrained from flowing laterally by a peripheral seal around the top of the core. This seal limits the flow rate of liquid metal, which may be sharply cooled during a scram, to the outlet nozzles. The chimneys and the grids are formed of a highly-refractory, high corrosion-resistant nickel-chromium-iron alloy which can withstand the stresses produced by temperature differences in the liquid metal. The chimneys are supported by pairs of plates, each pair held together by hollow stubs coaxial with, and encircling, the chimneys. The plates and stubs are a welded structure but, in the interest of economy, are composed of stainless steel which is not weld compatible with the refractory metal. The chimneys and stubs are secured together by shells of another nickel-chromium-iron alloy which is weld compatible with, and is welded to, the stubs and has about the same coefficient of expansion as the highly-refractory, high corrosion-resistant alloy.

Wick for metal vapor laser

DOEpatents

Duncan, David B.

1992-01-01

An improved wick for a metal vapor laser is made of a refractory metal cylinder, preferably molybdenum or tungsten for a copper laser, which provides the wicking surface. Alternately, the inside surface of the ceramic laser tube can be metalized to form the wicking surface. Capillary action is enhanced by using wire screen, porous foam metal, or grooved surfaces. Graphite or carbon, in the form of chunks, strips, fibers or particles, is placed on the inside surface of the wick to reduce water, reduce metal oxides and form metal carbides.

Characterization of refractory brick based on local raw material from Lampung Province - Indonesia

NASA Astrophysics Data System (ADS)

Amin, Muhammad; Suryana, Yayat I.; Isnugroho, Kusno; Aji, Bramantyo B.; Birawidha, David C.; Hendronursito, Yusup

2018-04-01

Refractories are non-metallic inorganic materials that are difficult to melt at high temperatures and used in high-temperature casting industries. Refractories are classified into their constituent mineral feed stocks, refractories having typical plot properties commonly called fire bricks. In the manufacture of refractory bricks that exist in the market during the use of mangrove materials derived from abroad that is from China. In this research the refractory brick materials used are quartz sand, feldspart, kaolin, bentonite, and ball clay. All materials come from local Lampung Province - Indonesia. The experiment, there are 7 kinds of experimental composition, made of plot shape with size 230 mm, 65 mm in thickness, 114 mm height mould using manual press machine with 10 tons power and burning at 1400°C for 5 hours. Refractory brick product is done by physical test in the form of porosity, specific gravity, compressive strength and XRF and SEM characteristics. The result of XRF characteristic of refractory brick composition of 1 to 5 compared to the refractory brick type SK 34 in the market and the result of composition 1 is a composition close to refractory brick composition type SK 34 namely SiO2 is 54.21 %, Al2O3 is 25.38 % and test Physical of Bulk density is 2.25 g/cm3, porosity is 18.98 % and compressive strength is 325 kg/cm2.

Refractory Wear Mechanisms in the Nonferrous Metal Industry: Testing and Modeling Results

NASA Astrophysics Data System (ADS)

Gregurek, D.; Ressler, A.; Reiter, V.; Franzkowiak, A.; Spanring, A.; Prietl, T.

2013-11-01

Nonferrous pyrometallurgical processes today operate at a high intensity requiring the best standards for the furnace refractory systems. From one plant to another, there is a range of process conditions such as temperature, slag chemistry, and feed types, and each of these parameters can influence refractory life. It is generally understood that process changes at plants can impact refractory life. The ability to test and understand refractory responses to a wide range of furnace operating conditions is therefore important. The RHI Technology Centre in Leoben, Austria is well equipped with laboratory and pilot plant facilities to evaluate refractory suitability over the range of conditions encountered in modern nonferrous pyrometallurgical systems. This article describes refractory testing at the RHI Technology Centre of the impact of two metallurgical slags on a number of different RHI test bricks. The slags were a fayalite slag and a calcium ferrite slag supplied by two smelter plants. High-temperature corrosion tests were carried out in a 250-mm-diameter induction furnace and a 165-mm-diameter short rotary kiln; each unit was lined with a number of refractory bricks and tested against attack by the particular slag. After testing, the refractory bricks were subjected to several laboratory tests to determine the extent of corrosion. Optimal refractory choices for the customers' plants were developed based on the test results.

[Somatostatin analogs for the treatment of advanced, hormone-refractory prostate cancer: a possibility for secondary hormonal ablation?].

PubMed

Schilling, D; Küfer, R; Kruck, S; Stenzl, A; Kuczyk, M A; Merseburger, A S

2008-10-01

Almost all patients with hormone-refractory prostate cancer under primary androgen deprivation therapy will develop progression, frequently initially marked by an asymptomatic increase of prostate-specific antigen (PSA). Recent data showed that taxane-based chemotherapy offers significant survival benefit to patients with advanced prostate cancer; however, the toxic side effects frequently exert a significant negative impact on the quality of life. At the androgen-independent stage of the cancer, before becoming hormone refractory, progression might still be delayed by secondary manipulation of either androgen or confounding receptors and their signaling pathways. Secondary hormonal manipulations traditionally included antiandrogen withdrawal, second-line antiandrogens, direct adrenal androgen inhibitors, estrogens, and progestins.We discuss the mode of action and application of somatostatin analogs as an emerging secondary hormonal treatment concept in patients with advanced prostate cancer on the basis of the current literature.

VIEW OF THE HYDROSPINNING EQUIPMENT IN BUILDING 865. THE HYDROSPINNING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW OF THE HYDROSPINNING EQUIPMENT IN BUILDING 865. THE HYDROSPINNING PROCESS FORMED METALS INTO DESIRED SHAPES BY ROLLERS WHILE THE METAL WAS ROTATED AT HIGH SPEED. BERYLLIUM, URANIUM, REFRACTORY METALS, AND OTHER NONFERROUS METALS WERE SPUN EITHER HOT OR COLD, INTO A VARIETY OF SHAPES. (11/9/73) - Rocky Flats Plant, Metal Research & Development Laboratory, South of Central Avenue at south end of terminus of Ninth Avenue, Golden, Jefferson County, CO

Ibrutinib versus temsirolimus in patients with relapsed or refractory mantle-cell lymphoma: an international, randomised, open-label, phase 3 study.

PubMed

Dreyling, Martin; Jurczak, Wojciech; Jerkeman, Mats; Silva, Rodrigo Santucci; Rusconi, Chiara; Trneny, Marek; Offner, Fritz; Caballero, Dolores; Joao, Cristina; Witzens-Harig, Mathias; Hess, Georg; Bence-Bruckler, Isabelle; Cho, Seok-Goo; Bothos, John; Goldberg, Jenna D; Enny, Christopher; Traina, Shana; Balasubramanian, Sriram; Bandyopadhyay, Nibedita; Sun, Steven; Vermeulen, Jessica; Rizo, Aleksandra; Rule, Simon

2016-02-20

Mantle-cell lymphoma is an aggressive B-cell lymphoma with a poor prognosis. Both ibrutinib and temsirolimus have shown single-agent activity in patients with relapsed or refractory mantle-cell lymphoma. We undertook a phase 3 study to assess the efficacy and safety of ibrutinib versus temsirolimus in relapsed or refractory mantle-cell lymphoma. This randomised, open-label, multicentre, phase 3 clinical trial enrolled patients with relapsed or refractory mantle-cell lymphoma confirmed by central pathology in 21 countries who had received one or more rituximab-containing treatments. Patients were stratified by previous therapy and simplified mantle-cell lymphoma international prognostic index score, and were randomly assigned with a computer-generated randomisation schedule to receive daily oral ibrutinib 560 mg or intravenous temsirolimus (175 mg on days 1, 8, and 15 of cycle 1; 75 mg on days 1, 8, and 15 of subsequent 21-day cycles). Randomisation was balanced by using randomly permuted blocks. The primary efficacy endpoint was progression-free survival assessed by a masked independent review committee with the primary hypothesis that ibrutinib compared with temsirolimus significantly improves progression-free survival. The analysis followed the intention-to-treat principle. The trial is ongoing and is registered with ClinicalTrials.gov (number NCT01646021) and with the EU Clinical Trials Register, EudraCT (number 2012-000601-74). Between Dec 10, 2012, and Nov 26, 2013, 280 patients were randomised to ibrutinib (n=139) or temsirolimus (n=141). Primary efficacy analysis showed significant improvement in progression-free survival (p<0·0001) for patients treated with ibrutinib versus temsirolimus (hazard ratio 0·43 [95% CI 0·32-0·58]; median progression-free survival 14·6 months [95% CI 10·4-not estimable] vs 6·2 months [4·2-7·9], respectively). Ibrutinib was better tolerated than temsirolimus, with grade 3 or higher treatment-emergent adverse events reported for 94 (68%) versus 121 (87%) patients, and fewer discontinuations of study medication due to adverse events for ibrutinib versus temsirolimus (9 [6%] vs 36 [26%]). Ibrutinib treatment resulted in significant improvement in progression-free survival and better tolerability versus temsirolimus in patients with relapsed or refractory mantle-cell lymphoma. These data lend further support to the positive benefit-risk ratio for ibrutinib in relapsed or refractory mantle-cell lymphoma. Janssen Research & Development, LLC. Copyright © 2016 Elsevier Ltd. All rights reserved.

METAL AEROSOL FORMATION IN A LABORATORY SWIRL FLAME INCINERATOR

EPA Science Inventory

The paper describes experiments performed using an 82 kW (280,000 Btu/hr) refractory-lined horizontal tunnel combustor to examine the aerosol particle size distribution (PSD) produced by simulated nickel, cadmium, and lead wastes injected into an incineration environment. Metal c...

Performance of coated columbium and tantalum alloys in plasma arc reentry simulation tests

NASA Technical Reports Server (NTRS)

Levine, S. R.; Merutka, J. P.

1974-01-01

The evaluation of coated refractory metals screened in stagnation model plasma arc tests is reported. Columbium alloys FS-85, C-129Y, and Cb-752 coated with Si-20Cr-20Fe (R512E) were tested at 1390 C. Three silicide coatings on Ta-10W were tested at 1470 C. Half-hour cycles and a 6500 N/sqm stagnation pressure were used. The best R512E coated columbium alloy was FS-85 with first local coating breakdowns occurring in 12 to 50 cycles. At coating defects, low metal recession rates (0.005 mm/min) were generally observed on coated columbium alloys while high rates (0.15 mm/min) were observed on coated Ta-10W. Coated columbium suffered large emittance losses (to below 0.7) due to surface refractory metal pentoxide formation.

Convoluted nozzle design for the RL10 derivative 2B engine

NASA Technical Reports Server (NTRS)

1985-01-01

The convoluted nozzle is a conventional refractory metal nozzle extension that is formed with a portion of the nozzle convoluted to show the extendible nozzle within the length of the rocket engine. The convoluted nozzle (CN) was deployed by a system of four gas driven actuators. For spacecraft applications the optimum CN may be self-deployed by internal pressure retained, during deployment, by a jettisonable exit closure. The convoluted nozzle is included in a study of extendible nozzles for the RL10 Engine Derivative 2B for use in an early orbit transfer vehicle (OTV). Four extendible nozzle configurations for the RL10-2B engine were evaluated. Three configurations of the two position nozzle were studied including a hydrogen dump cooled metal nozzle and radiation cooled nozzles of refractory metal and carbon/carbon composite construction respectively.

Advanced Ceramics for Use as Fuel Element Materials in Nuclear Thermal Propulsion Systems

NASA Technical Reports Server (NTRS)

Valentine, Peter G.; Allen, Lee R.; Shapiro, Alan P.

2012-01-01

With the recent start (October 2011) of the joint National Aeronautics and Space Administration (NASA) and Department of Energy (DOE) Advanced Exploration Systems (AES) Nuclear Cryogenic Propulsion Stage (NCPS) Program, there is renewed interest in developing advanced ceramics for use as fuel element materials in nuclear thermal propulsion (NTP) systems. Three classes of fuel element materials are being considered under the NCPS Program: (a) graphite composites - consisting of coated graphite elements containing uranium carbide (or mixed carbide), (b) cermets (ceramic/metallic composites) - consisting of refractory metal elements containing uranium oxide, and (c) advanced carbides consisting of ceramic elements fabricated from uranium carbide and one or more refractory metal carbides [1]. The current development effort aims to advance the technology originally developed and demonstrated under Project Rover (1955-1973) for the NERVA (Nuclear Engine for Rocket Vehicle Application) [2].

System and method for producing metallic iron

DOEpatents

Englund, David J.; Schlichting, Mark; Meehan, John; Crouch, Jeremiah; Wilson, Logan

2014-07-29

A method of production of metallic iron nodules comprises assembling a hearth furnace having a moveable hearth comprising refractory material and having a conversion zone and a fusion zone, providing a hearth material layer comprising carbonaceous material on the refractory material, providing a layer of reducible material comprising and iron bearing material arranged in discrete portions over at least a portion of the hearth material layer, delivering oxygen gas into the hearth furnace to a ratio of at least 0.8:1 ponds of oxygen to pounds of iron in the reducible material to heat the conversion zone to a temperature sufficient to at least partially reduce the reducible material and to heat the fusion zone to a temperature sufficient to at least partially reduce the reducible material, and heating the reducible material to form one or more metallic iron nodules and slag.

Electrodeposition of Refractory Carbide Coatings.

DTIC Science & Technology

1982-12-30

refractory carbide coatings from molten salts is described. It consists of the simultaneous reduction of the appropriate metal species dissolved in the...Electrodeposition Molden salts 20. ASSTRACT (Continue an reve.e. 0g.. It necooom wed identify bp block nu.be) A novel method for electrodepositing...respectively. Electrolysis resulted in the formation of millimeter-size crystals on the walls of the graphite crucible which served as the cathode. Analysis of

High temperature solar selective coatings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kennedy, Cheryl E

Improved solar collectors (40) comprising glass tubing (42) attached to bellows (44) by airtight seals (56) enclose solar absorber tubes (50) inside an annular evacuated space (54. The exterior surfaces of the solar absorber tubes (50) are coated with improved solar selective coatings {48} which provide higher absorbance, lower emittance and resistance to atmospheric oxidation at elevated temperatures. The coatings are multilayered structures comprising solar absorbent layers (26) applied to the meta surface of the absorber tubes (50), typically stainless steel, topped with antireflective Savers (28) comprising at least two layers 30, 32) of refractory metal or metalloid oxides (suchmore » as titania and silica) with substantially differing indices of refraction in adjacent layers. Optionally, at least one layer of a noble metal such as platinum can be included between some of the layers. The absorbent layers cars include cermet materials comprising particles of metal compounds is a matrix, which can contain oxides of refractory metals or metalloids such as silicon. Reflective layers within the coating layers can comprise refractory metal silicides and related compounds characterized by the formulas TiSi. Ti.sub.3SiC.sub.2, TiAlSi, TiAN and similar compounds for Zr and Hf. The titania can be characterized by the formulas TiO.sub.2, Ti.sub.3O.sub.5. TiOx or TiO.sub.xN.sub.1-x with x 0 to 1. The silica can be at least one of SiO.sub.2, SiO.sub.2x or SiO.sub.2xN.sub.1-x with x=0 to 1.« less

Refractory amorphous metallic (W/0.6/ Re/0.4/)76B24 coatings on steel substrates

NASA Technical Reports Server (NTRS)

Thakoor, A. P.; Lamb, J. L.; Khanna, S. K.; Mehra, M.; Johnson, W. L.

1985-01-01

Refractory metallic coatings of (W/0.6/ Re/0.4/)76B24 (WReB) have been deposited onto glass, quartz, and heat-treated AISI 52100 bearing steel substrates by dc magnetron sputtering. As-deposited WReB films are amorphous, as shown by their diffuse X-ray diffraction patterns; chemically homogeneous, according to secondary ion mass spectrometry (SIMS) analysis; and they exhibit a very high (approximately 1000 C) crystallization temperature. Adhesion strength of these coatings on heat-treated AISI 52100 steel is in excess of approximately 20,000 psi and they possess high microhardness (approximately 2400 HV50). Unlubricated wear resistance of such hard and adherent amorphous metallic coatings on AISI 52100 steel is studied using the pin-on-disc method under various loading conditions. Amorphous metallic WReB coatings, about 4 microns thick, exhibit an improvement of more than two and a half orders of magnitude in the unlubricated wear resistance over that of the uncoated AISI 52100 steel.

Refractory metal joining for first wall applications

NASA Astrophysics Data System (ADS)

Cadden, C. H.; Odegard, B. C.

2000-12-01

The potential use of high temperature coolant (e.g. 900°C He) in first wall structures would preclude the applicability of copper alloy heat sink materials and refractory metals would be potential replacements. Brazing trials were conducted in order to examine techniques to join tungsten armor to high tungsten (90-95 wt%) or molybdenum TZM heat sink materials. Palladium-, nickel- and zirconium-based filler metals were investigated using brazing temperatures ranging from 1000°C to 1275°C. Palladium-nickel and palladium-cobalt braze alloys were successful in producing generally sound metallurgical joints in tungsten alloy/tungsten couples, although there was an observed tendency for the pure tungsten armor material to exhibit grain boundary cracking after bonding. The zirconium- and nickel-based filler metals produced defect-containing joints, specifically cracking and porosity, respectively. The palladium-nickel braze alloy produced sound joints in the Mo TZM/tungsten couple. Substitution of a lanthanum oxide-containing, fine-grained tungsten material (for the pure tungsten) eliminated the observed tungsten grain boundary cracking.

Carbide and carbonitride surface treatment method for refractory metals

DOEpatents

Meyer, Glenn A.; Schildbach, Marcus A.

1996-01-01

A carbide and carbonitride surface treatment method for refractory metals is provided, in steps including, heating a part formed of boron, chromium, hafnium, molybdenum, niobium, tantalum, titanium, tungsten or zirconium, or alloys thereof, in an evacuated chamber and then introducing reaction gases including nitrogen and hydrogen, either in elemental or water vapor form, which react with a source of elemental carbon to form carbon-containing gaseous reactants which then react with the metal part to form the desired surface layer. Apparatus for practicing the method is also provided, in the form of a carbide and carbonitride surface treatment system (10) including a reaction chamber (14), a source of elemental carbon (17), a heating subassembly (20) and a source of reaction gases (23). Alternative methods of providing the elemental carbon (17) and the reaction gases (23) are provided, as well as methods of supporting the metal part (12), evacuating the chamber (14) with a vacuum subassembly (18) and heating all of the components to the desired temperature.

Processing and fabrication of mixed uranium/refractory metal carbide fuels with liquid-phase sintering

NASA Astrophysics Data System (ADS)

Knight, Travis W.; Anghaie, Samim

2002-11-01

Optimization of powder processing techniques were sought for the fabrication of single-phase, solid-solution mixed uranium/refractory metal carbide nuclear fuels - namely (U, Zr, Nb)C. These advanced, ultra-high temperature nuclear fuels have great potential for improved performance over graphite matrix, dispersed fuels tested in the Rover/NERVA program of the 1960s and early 1970s. Hypostoichiometric fuel samples with carbon-to-metal ratios of 0.98, uranium metal mole fractions of 5% and 10%, and porosities less than 5% were fabricated. These qualities should provide for the longest life and highest performance capability for these fuels. Study and optimization of processing methods were necessary to provide the quality assurance of samples for meaningful testing and assessment of performance for nuclear thermal propulsion applications. The processing parameters and benefits of enhanced sintering by uranium carbide liquid-phase sintering were established for the rapid and effective consolidation and formation of a solid-solution mixed carbide nuclear fuel.

Clinical outcomes of intravenous immunoglobulin therapy in refractory uveitis.

PubMed

Garcia-Geremias, M; Carreño, E; Epps, S J; Lee, R W J; Dick, A D

2015-04-01

Intravenous immunoglobulin (IVIg) therapy has multiple mechanisms of immunomodulatory action. We wished therefore to assess its efficacy in a spectrum of patients with refractory uveitis. Retrospective review of clinical charts was conducted to document response to IVIg treatment in consecutive patients with treatment-refractory uveitis. Main outcome measures were control of intraocular inflammation, visual acuity, progression of the disease, and complications. Four (two male) patients, with a mean age at the beginning of the treatment of 47 years (range: 39-64), were included in the study. Indication for treatment was patients with active non-infectious uveitis refractory to steroids and immunomodulatory therapy. All patients received a course of 0.5 g/kg per day of IVIg for three consecutive days, repeating this course at a mean of 11 week (range: 2-39 weeks) intervals when indicated clinically. The median duration of the IVIg therapy was 7 months (range: 3-14 months). In three patients treatment resulted in stabilisation and prevention of progression of the disease, and additionally in two patients it facilitated a decrease in prednisolone dose. Treatment failed to induce long-term remission in one patient with recurrence of macular oedema. IVIg was well tolerated with neither immediate nor longer-term adverse events observed. In three out of four cases IVIg was an effective adjunctive therapy and well tolerated for the management of treatment-refractory uveitis.

Brentuximab vedotin (SGN-35) in patients with transplant-naive relapsed/refractory Hodgkin lymphoma.

PubMed

Sasse, Stephanie; Rothe, Achim; Goergen, Helen; Eichenauer, Dennis A; Lohri, Andreas; Kreher, Stephan; Jäger, Ulrich; Bangard, Christopher; Kuhnert, Georg; Böll, Boris; von Tresckow, Bastian; Engert, Andreas

2013-10-01

Only limited data are available on the role of brentuximab vedotin (SGN-35) in transplant-naive relapsed or refractory patients with Hodgkin lymphoma (HL). We thus retrospectively analyzed 14 patients with primary refractory or relapsed HL who were treated with brentuximab vedotin as single agent in a named patient program, who had not received prior high-dose chemotherapy (HDCT) and autologous stem cell transplant (ASCT) due to refractory disease (n = 9), comorbidity (n = 4) and unknown reasons (n = 1). Brentuximab vedotin resulted in an overall response rate of 71% (10/14) with five complete responses (CRs). Five of those patients with refractory disease and four patients with relevant comorbidity responded. Consolidating ASCT (n = 4) or allogeneic SCT (n = 1) was performed in five patients. Median progression-free survival (PFS) was 9 months and the median overall survival (OS) was not reached. These data indicate the therapeutic efficacy of brentuximab vedotin in chemotherapy-refractory transplant-naive patients with HL.

Electro Processing Research

NASA Technical Reports Server (NTRS)

1982-01-01

Electroprocessing which is concerned with fluid dynamics of the electroreduction process to determine how it may be modified to improve the quality of the deposit was studied. Experimental techniques are used in this research. These techniques include laser Schlieren photography, laser Doppler velocimetry, and frequency spectrum analysis. Projects involve fluid flow studies of zinc plating in aqueous and molten salt electrolytes, study of cell design for magnesium chlorides electrolysis, digital signal analysis of manganese electrodeposition in molten chlorides, and electroplating of molybdenum from low melting salts. It is anticipated that the use of refractory metals as constructed materials in engineering will increase. Their electrodeposition from molten salt electrolytes is important in the extraction metallurgy of refractory metals.

REFRACTORY DIE FOR EXTRUDING URANIUM

DOEpatents

Creutz, E.C.

1959-08-11

A die is presented for the extrusion of metals, said die being formed of a refractory complex oxide having the composition M/sub n/O/sub m/R/sub x/O/sub y/ where M is magnesium, zinc, manganese, or iron, R is aluminum, chromic chromium, ferric iron, or manganic manganese, and m, n, x, and y are whole numbers. Specific examples are spinel, magnesium aluminate, magnetite, magnesioferrite, chromite, and franklinite.

T-111 Rankine system corrosion test loop, volume 1

NASA Technical Reports Server (NTRS)

Harrison, R. W.; Hoffman, E. E.; Smith, J. P.

1975-01-01

Results are given of a program whose objective was to determine the performance of refractory metal alloys in a two loop Rankine test system. The test system consisted of a circulating lithium circuit heated to 1230 C maximum transferring heat to a boiling potassium circuit with a 1170 C superheated vapor temperature. The results demonstrate the suitability of the selected refractory alloys to perform from a chemical compatibility standpoint.

The use of retrievable fully covered self-expanding metal stent in refractory postoperative restenosis of benign esophageal stricture in children.

PubMed

Zhang, Jie; Ren, Lixin; Huo, Jirong; Zhu, Zhiyuan; Liu, Deliang

2013-11-01

This study analyzes the efficacy and safety of a retrievable, fully covered self-expanding metal stent (cSEMS) in the treatment of refractory benign esophageal restenosis in children. This is a retrospective analysis of the application of a newly designed cSEMS in treating refractory benign postoperative restenosis in five children with ages ranging from 16 months to 8 years. Efficacy and safety were evaluated during the follow-up period. cSEMS with or without an antireflux valve at the distal end were successfully placed and removed in five children. These five patients were followed up for 4-12 months after stent removal. Among the five patients, ulcerative stricture was observed in two patients because of reflux esophagitis, while three patients showed no signs of stricture recurrence. Stent migration was observed in three patients, two of which required the stent to be reset. The narrow esophagus was successfully expended to a diameter of 12-13 mm. Besides the observation of mild granulation tissue growth in one case, no severe complications were observed during surgery and after stent placement. Our study suggests that a retrievable, fully covered SEMS is safe and partially effective for treating refractory benign postoperative esophageal restenosis in children during short-term observation. © 2013.

40 CFR 442.2 - General definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., organic chemicals including: alcohols, aldehydes, formaldehydes, phenols, peroxides, organic salts, amines..., glycerines, and organic polymers; refractory organic compounds including: ketones, nitriles, organo-metallic...

High temperature oxidation resistant cermet compositions

NASA Technical Reports Server (NTRS)

Phillips, W. M. (Inventor)

1976-01-01

Cermet compositions are designed to provide high temperature resistant refractory coatings on stainless steel or molybdenum substrates. A ceramic mixture of chromium oxide and aluminum oxide form a coating of chromium oxide as an oxidation barrier around the metal particles, to provide oxidation resistance for the metal particles.

Production of fiberglass/metal composite material suitable for building habitat and manufacturing facilities

NASA Technical Reports Server (NTRS)

1987-01-01

The production of a fiberglass/metal composite material suitable for building habitats and manufacturing facilities was the project for Clemson. The concept and development of the knowledge necessary to produce glass fibers originated in the spring semester. During the summer, while at Johnson Space Center, fiberglass from a rock composition similar to ones found at the Apollo 16 site on the moon was successfully produced. The project this year was a continuation of last year's studies. We addressed the following problems which emerged as the work progressed: (1) Methods for coating the fibers with a metal were explored. We manufactured composites in two stages: Glass fibers without any coating on them; and fibers coated with metals as they were made. This proved to be a difficult process. Future activities include using a chemical vapor deposition process on fibers which have been made. (2) A glass furnace was developed which relies primarily on solar energy for melting the glass. The temperature of the melted glass is maintained by electrical means. The design is for 250 kg of glass per day. An electrical engineering student developed a scheme for controlling the melting and manufacturing process from the earth. This was done to minimize the human risk. Graphite refractories are relied on to contain the melt. (3) The glass composition chosen for the project is a relatively pure anorthite which is available in the highland regions of the lunar surface. A major problems with this material is that it melts at a comparatively high temperature. This problem will be solved by using graphite refractory materials for the furnace. The advantage of this glass composition is that it is very stable and does not tend to crystallize. (4) We have also refined the experimental furnace and fiber making machinery which we will be using at Johnson Space Center this summer. We believe that we will be able to draw and coat glass fibers in a vacuum for use in composites. We intend to make and test the mechanical properties of these composites.

Application of diffusion barriers to the refractory fibers of tungsten, columbium, carbon and aluminum oxide

NASA Technical Reports Server (NTRS)

Douglas, F. C.; Paradis, E. L.; Veltri, R. D.

1973-01-01

A radio frequency powered ion-plating system was used to plate protective layers of refractory oxides and carbide onto high strength fiber substrates. Subsequent overplating of these combinations with nickel and titanium was made to determine the effectiveness of such barrier layers in preventing diffusion of the overcoat metal into the fibers with consequent loss of fiber strength. Four substrates, five coatings, and two metal matrix materials were employed for a total of forty material combinations. The substrates were tungsten, niobium, NASA-Hough carbon, and Tyco sapphire. The diffusion-barrier coatings were aluminum oxide, yttrium oxide, titanium carbide, tungsten carbide with 14% cobalt addition, and zirconium carbide. The metal matrix materials were IN 600 nickel and Ti 6/4 titanium. Adhesion of the coatings to all substrates was good except for the NASA-Hough carbon, where flaking off of the oxide coatings in particular was observed.

Biotechnology for the extractive metals industries

NASA Astrophysics Data System (ADS)

Brierley, James A.

1990-01-01

Biotechnology is an alternative process for the extraction of metals, the beneficiation of ores, and the recovery of metals from aqueous systems. Currently, microbial-based processes are used for leaching copper and uranium, enhancing the recovery of gold from refractory ores, and treating industrial wastewater to recover metal values. Future developments, emanating from fundamental and applied research and advances through genetic engineering, are expected to increase the use and efficiency of these biotechnological processes.

Cyclophosphamide's addition in relapsed/refractory multiple myeloma patients with biochemical progression during lenalidomide-dexamethasone treatment.

PubMed

Cesini, Laura; Siniscalchi, Agostina; Grammatico, Sara; Andriani, Alessandro; Fiorini, Alessia; De Rosa, Luca; Za, Tommaso; Rago, Angela; Caravita, Tommaso; Petrucci, Maria Teresa

2018-05-02

The aim of this study was to evaluate the addition of cyclophosphamide in relapsed-refractory multiple myeloma patients (RRMM) who experienced biochemical relapse or progression without CRAB, during treatment with lenalidomide and dexamethasone (Rd), to slow down the progression in active relapse. This analysis included 31 patients with RRMM treated with Rd who received cyclophosphamide (CRd) at biochemical relapse. The CRd regimen was continued until disease progression. The median number of CRd cycles administered was 8 (range: 1-35). A response was observed in 9 (29%) patients. After a median observation time of 11 months, the median overall survival (OS) from the beginning of CRd was 17.7 months. The median progression-free survival (PFS) from the beginning of CRd was 13.1 months. The addition of cyclophosphamide delays the progression in patients who present a biochemical relapse during Rd treatment. The response rate and the duration of PFS obtained with minimal toxicities and low costs induced us to setting up a randomized clinical trial. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Processing of solid solution, mixed uranium/refractory metal carbides for advanced space nuclear power and propulsion systems

NASA Astrophysics Data System (ADS)

Knight, Travis Warren

Nuclear thermal propulsion (NTP) and space nuclear power are two enabling technologies for the manned exploration of space and the development of research outposts in space and on other planets such as Mars. Advanced carbide nuclear fuels have been proposed for application in space nuclear power and propulsion systems. This study examined the processing technologies and optimal parameters necessary to fabricate samples of single phase, solid solution, mixed uranium/refractory metal carbides. In particular, the pseudo-ternary carbide, UC-ZrC-NbC, system was examined with uranium metal mole fractions of 5% and 10% and corresponding uranium densities of 0.8 to 1.8 gU/cc. Efforts were directed to those methods that could produce simple geometry fuel elements or wafers such as those used to fabricate a Square Lattice Honeycomb (SLHC) fuel element and reactor core. Methods of cold uniaxial pressing, sintering by induction heating, and hot pressing by self-resistance heating were investigated. Solid solution, high density (low porosity) samples greater than 95% TD were processed by cold pressing at 150 MPa and sintering above 2600 K for times longer than 90 min. Some impurity oxide phases were noted in some samples attributed to residual gases in the furnace during processing. Also, some samples noted secondary phases of carbon and UC2 due to some hyperstoichiometric powder mixtures having carbon-to-metal ratios greater than one. In all, 33 mixed carbide samples were processed and analyzed with half bearing uranium as ternary carbides of UC-ZrC-NbC. Scanning electron microscopy, x-ray diffraction, and density measurements were used to characterize samples. Samples were processed from powders of the refractory mono-carbides and UC/UC 2 or from powders of uranium hydride (UH3), graphite, and refractory metal carbides to produce hypostoichiometric mixed carbides. Samples processed from the constituent carbide powders and sintered at temperatures above the melting point of UC showed signs of liquid phase sintering and were shown to be largely solid solutions. Pre-compaction of mixed carbide powders prior to sintering was shown to be necessary to achieve high densities. Hypostoichiometric, samples processed at 2500 K exhibited only the initial stage of sintering and solid solution formation. Based on these findings, a suggested processing methodology is proposed for producing high density, solid solution, mixed carbide fuels. Pseudo-binary, refractory carbide samples hot pressed at 3100 K and 6 MPa showed comparable densities (approximately 85% of the theoretical value) to samples processed by cold pressing and sintering at temperatures of 2800 K.

Alloy design for intrinsically ductile refractory high-entropy alloys

NASA Astrophysics Data System (ADS)

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.

Advanced composite alloys for constructional parts of robots

NASA Astrophysics Data System (ADS)

Issin, D. K.; Zholdubayeva, Zh D.; Neshina, Y. G.; Alkina, A. D.; Khuangan, N.; Rahimova, G. M.

2018-05-01

In recent years all over the world special attention has been paid to the development and implementation of nanostructured materials possessing unique properties and opening fascinating prospects for the development of technical progress in various fields of human activities. A special place can be given to the development of service robots, the market of which is actively developing. There is problem associated mainly with the lack of heat-strengthened alloys which consists in low thermal stability of the alloy properties under the conditions of elevated variable temperatures and loads. The article presents studies to assess the effect of composition, the amounts of refractory nanoscale particles and methods for their introduction into the melt on the structure and properties in nanostructured composite aluminum alloys. The powders of metals, alloys, as well as silicon carbide and aluminum oxide were used to produce the nanostructured powder composite materials. As a result of the research, NPCM compositions containing micro-size particles of transition metals that are carriers of nanosized reinforcing particles and initiators of the formation of an intermetallide of endogenous origin in a melt.

Annual Research Progress Report, Fiscal Year 1979,

DTIC Science & Technology

1979-10-01

Infusion on 58 Hemoglobin Oxygen Carrying Patterns in Man. (0) (PR) C-6-78 Minoxidil as an Anti-Hypertensive in Patients 59 Refractory to Available...aspirin. Ann. Int. Med. 89:1006, 1978. Rubin, E.N., Walker, B.K., Ersler, A.J., et al. Euthyroid aplasia complicating collagen vascular disease...Texas 78234 CLINICAL INVESTIGATION SERVICE INVESTIGATION PROJECT RESUME TITLE: Minoxidil as an Anti-Hypertensive in Patients Refractory to Available

Annual Research Progress Report, Fiscal Year 1979,

DTIC Science & Technology

1979-10-01

Chemoimmunotherapy of Carcinoma of the Large 27 Bowel. (T) 77-8 Minoxidil as an Antihypertensive in Patients 29 Refractory to Available Medications. (T) 77-11...INVESTIGATION SERVICE INVESTIGATION PROJECT RESUME TITLE: Minoxidil as an Antihypertensive in Patients Refractory to Available Medications. WORK UNIT...NO: 77-8 (Satellite Protocol of FAMC) PRINCIPAL INVESTIGATOR: James H. Wilkin, MD, LTC, MD OBJECTIVES To test the hypothesis that minoxidil is an

Device for hydrogen separation and method

DOEpatents

Paglieri, Stephen N [White Rock, NM; Anderson, Iver E [Ames, IA; Terpstra, Robert L [Ames, IA

2009-11-03

A device for hydrogen separation has a porous support and hydrogen separation material on the support. The support is prepared by heat treatment of metal microparticles, preferably of iron-based or nickel-based alloys that also include aluminum and/or yttrium. The hydrogen separation material is then deposited on the support. Preferred hydrogen separation materials include metals such as palladium, alloys, platinum, refractory metals, and alloys.

System and process for aluminization of metal-containing substrates

DOEpatents

Chou, Yeong-Shyung; Stevenson, Jeffry W.

2017-12-12

A system and method are detailed for aluminizing surfaces of metallic substrates, parts, and components with a protective alumina layer in-situ. Aluminum (Al) foil sandwiched between the metallic components and a refractory material when heated in an oxidizing gas under a compression load at a selected temperature forms the protective alumina coating on the surface of the metallic components. The alumina coating minimizes evaporation of volatile metals from the metallic substrates, parts, and components in assembled devices that can degrade performance during operation at high temperature.

System and process for aluminization of metal-containing substrates

DOEpatents

Chou, Yeong-Shyung; Stevenson, Jeffry W

2015-11-03

A system and method are detailed for aluminizing surfaces of metallic substrates, parts, and components with a protective alumina layer in-situ. Aluminum (Al) foil sandwiched between the metallic components and a refractory material when heated in an oxidizing gas under a compression load at a selected temperature forms the protective alumina coating on the surface of the metallic components. The alumina coating minimizes evaporation of volatile metals from the metallic substrates, parts, and components in assembled devices during operation at high temperature that can degrade performance.

Method of removing sulfur emissions from a fluidized-bed combustion process

DOEpatents

Vogel, Gerhard John; Jonke, Albert A.; Snyder, Robert B.

1978-01-01

Alkali metal or alkaline earth metal oxides are impregnated within refractory support material such as alumina and introduced into a fluidized-bed process for the combustion of coal. Sulfur dioxide produced during combustion reacts with the metal oxide to form metal sulfates within the porous support material. The support material is removed from the process and the metal sulfate regenerated to metal oxide by chemical reduction. Suitable pore sizes are originally developed within the support material by heat-treating to accommodate both the sulfation and regeneration while still maintaining good particle strength.

Thermostructural applications of heat pipes for cooling leading edges of high-speed aerospace vehicles

NASA Technical Reports Server (NTRS)

Camarda, Charles J.; Glass, David E.

1992-01-01

Heat pipes have been considered for use on wing leading edge for over 20 years. Early concepts envisioned metal heat pipes cooling a metallic leading edge. Several superalloy/sodium heat pipes were fabricated and successfully tested for wing leading edge cooling. Results of radiant heat and aerothermal testing indicate the feasibility of using heat pipes to cool the stagnation region of shuttle-type space transportation systems. The test model withstood a total seven radiant heating tests, eight aerothermal tests, and twenty-seven supplemental radiant heating tests. Cold-wall heating rates ranged from 21 to 57 Btu/sq ft-s and maximum operating temperatures ranged from 1090 to 1520 F. Follow-on studies investigated the application of heat pipes to cool the stagnation regions of single-stage-to-orbit and advanced shuttle vehicles. Results of those studies indicate that a 'D-shaped' structural design can reduce the mass of the heat-pipe concept by over 44 percent compared to a circular heat-pipe geometry. Simple analytical models for heat-pipe startup from the frozen state (working fluid initially frozen) were adequate to approximate transient, startup, and steady-state heat-pipe performance. Improvement in analysis methods has resulted in the development of a finite-element analysis technique to predict heat-pipe startup from the frozen state. However, current requirements of light-weight design and reliability suggest that metallic heat pipes embedded in a refractory composite material should be used. This concept is the concept presently being evaluated for NASP. A refractory-composite/heat-pipe-cooled wing leading edge is currently being considered for the National Aero-Space Plane (NASP). This concept uses high-temperature refractory-metal/lithium heat pipes embedded within a refractory-composite structure and is significantly lighter than an actively cooled wing leading edge because it eliminates the need for active cooling during ascent and descent. Since the NASP vehicle uses cryogenic hydrogen to cool structural components and then burns this fuel in the combustor, hydrogen necessary for descent cooling only, when the vehicle is unpowered, is considered to be a weight penalty. Details of the design of the refractory-composite/heat-pipe-cooled wing leading edge are currently being investigated. Issues such as thermal contact resistance and thermal stress are also being investigated.

Thermostructural applications of heat pipes for cooling leading edges of high-speed aerospace vehicles

NASA Astrophysics Data System (ADS)

Camarda, Charles J.; Glass, David E.

1992-10-01

Heat pipes have been considered for use on wing leading edge for over 20 years. Early concepts envisioned metal heat pipes cooling a metallic leading edge. Several superalloy/sodium heat pipes were fabricated and successfully tested for wing leading edge cooling. Results of radiant heat and aerothermal testing indicate the feasibility of using heat pipes to cool the stagnation region of shuttle-type space transportation systems. The test model withstood a total seven radiant heating tests, eight aerothermal tests, and twenty-seven supplemental radiant heating tests. Cold-wall heating rates ranged from 21 to 57 Btu/sq ft-s and maximum operating temperatures ranged from 1090 to 1520 F. Follow-on studies investigated the application of heat pipes to cool the stagnation regions of single-stage-to-orbit and advanced shuttle vehicles. Results of those studies indicate that a 'D-shaped' structural design can reduce the mass of the heat-pipe concept by over 44 percent compared to a circular heat-pipe geometry. Simple analytical models for heat-pipe startup from the frozen state (working fluid initially frozen) were adequate to approximate transient, startup, and steady-state heat-pipe performance. Improvement in analysis methods has resulted in the development of a finite-element analysis technique to predict heat-pipe startup from the frozen state. However, current requirements of light-weight design and reliability suggest that metallic heat pipes embedded in a refractory composite material should be used. This concept is the concept presently being evaluated for NASP. A refractory-composite/heat-pipe-cooled wing leading edge is currently being considered for the National Aero-Space Plane (NASP). This concept uses high-temperature refractory-metal/lithium heat pipes embedded within a refractory-composite structure and is significantly lighter than an actively cooled wing leading edge because it eliminates the need for active cooling during ascent and descent. Since the NASP vehicle uses cryogenic hydrogen to cool structural components and then burns this fuel in the combustor, hydrogen necessary for descent cooling only, when the vehicle is unpowered, is considered to be a weight penalty. Details of the design of the refractory-composite/heat-pipe-cooled wing leading edge are currently being investigated. Issues such as thermal contact resistance and thermal stress are also being investigated.

Advanced Materials and Fabrication Techniques for the Orion Attitude Control Motor

NASA Technical Reports Server (NTRS)

Gorti, Sridhar; Holmes, Richard; O'Dell, John; McKechnie, Timothy; Shchetkovskiy, Anatoliy

2013-01-01

Rhenium, with its high melting temperature, excellent elevated temperature properties, and lack of a ductile-to-brittle transition temperature (DBTT), is ideally suited for the hot gas components of the ACM (Attitude Control Motor), and other high-temperature applications. However, the high cost of rhenium makes fabricating these components using conventional fabrication techniques prohibitive. Therefore, near-net-shape forming techniques were investigated for producing cost-effective rhenium and rhenium alloy components for the ACM and other propulsion applications. During this investigation, electrochemical forming (EL-Form ) techniques were evaluated for producing the hot gas components. The investigation focused on demonstrating that EL-Form processing techniques could be used to produce the ACM flow distributor. Once the EL-Form processing techniques were established, a representative rhenium flow distributor was fabricated, and samples were harvested for material properties testing at both room and elevated temperatures. As a lower cost and lighter weight alternative to an all-rhenium component, rhenium- coated graphite and carbon-carbon were also evaluated. The rhenium-coated components were thermal-cycle tested to verify that they could withstand the expected thermal loads during service. High-temperature electroforming is based on electrochemical deposition of compact layers of metals onto a mandrel of the desired shape. Mandrels used for electro-deposition of near-net shaped parts are generally fabricated from high-density graphite. The graphite mandrel is easily machined and does not react with the molten electrolyte. For near-net shape components, the inner surface of the electroformed part replicates the polished graphite mandrel. During processing, the mandrel itself becomes the cathode, and scrap or refined refractory metal is the anode. Refractory metal atoms from the anode material are ionized in the molten electrolytic solution, and are deposited onto the cathodic mandrel by electrochemical reduction. Rotation of the mandrel ensures uniform distribution of refractory material. The EL-Form process allows for manufacturing in an inert atmosphere with deposition rates from 0.0004 to 0.002 in./h (10.2 to 50.8 m/h). Thicknesses typically range from microns to greater than 0.5 in. (13 mm). The refractory component produced is fabricated, dependably, to within one micron of the desired tolerances with no shrinkage or distortion as in other refractory metal manufacture techniques. The electroforming process has been used to produce solid, nonporous deposits of rhenium, iridium, niobium, tungsten, and their alloys.

The relation between bevacizumab injection and the formation of subretinal fibrosis in diabetic patients with panretinal photocoagulation.

PubMed

Batman, Cosar; Ozdamar, Yasemin

2010-01-01

To report the development of subretinal fibrosis after the injection of intravitreal bevacizumab in eyes with proliferative diabetic retinopathy (PDR) refractory to panretinal laser photocoagulation (PRP). Twenty-one eyes of 15 patients treated with PRP and intravitreal injection of bevacizumab were included in this study. The clinical outcomes of 21 eyes having subretinal fibrosis after intravitreal bevacizumab injection were reviewed. There were 9 men and 6 women with a mean age of 51.3 +/- 8.9 years. All eyes had PDR refractory to panretinal photocoagulation and were treated with at least one intravitreal injection of 1.25 mg of bevacizumab (mean number of injections: 1.8). Before injection, there was subretinal fibrosis in 5 eyes and vitreoretinal traction in 19 eyes. After a mean follow-up period of 7 months, the development or progression of subretinal fibrosis was detected in all eyes. Intravitreal injection of bevacizumab may cause formation or progression of subretinal fibrosis in patients with PDR refractory to PRP. Copyright 2010, SLACK Incorporated.

Gas atomization synthesis of refractory or intermetallic compounds and supersaturated solid solutions

DOEpatents

Anderson, Iver E.; Lograsso, Barbara K.; Ellis, Timothy W.

1994-01-01

A metallic melt is atomized using a high pressure atomizing gas wherein the temperature of the melt and the composition of the atomizing gas are selected such that the gas and melt react in the atomization spray zone to form a refractory or intermetallic compound in the as-atomized powder particles. A metallic melt is also atomized using a high pressure atomizing gas mixture gas wherein the temperature of the melt and the ratio of a reactive gas to a carrier gas are selected to form powder particles comprising a supersaturated solid solution of the atomic species of the reactive gas in the particles. The powder particles are then heat treated to precipitate dispersoids in-situ therein to form a dispersion strengthened material.

Magnesium fluoride as energy storage medium for spacecraft solar thermal power systems

NASA Technical Reports Server (NTRS)

Lurio, Charles A.

1992-01-01

MgF2 was investigated as a phase-change energy-storage material for LEO power systems using solar heat to run thermal cycles. It provides a high heat of fusion per unit mass at a high melting point (1536 K). Theoretical evaluation showed the basic chemical compatibility of liquid MgF2 with refractory metals at 1600 K, though transient high pressures of H2 can occur in a closed container due to reaction with residual moisture. The compatibility was tested in two refractory metal containers for over 2000 h. Some showed no deterioration, while there was evidence that the fluoride reacted with hafnium in others. Corollary tests showed that the MgF2 supercooled by 10-30 K and 50-90 K.

Joining of materials using laser heating

DOEpatents

Cockeram, Brian V.; Hicks, Trevor G.; Schmid, Glenn C.

2003-07-01

A method for diffusion bonding ceramic layers such as boron carbide, zirconium carbide, or silicon carbide uses a defocused laser beam to heat and to join ceramics with the use of a thin metal foil insert. The metal foil preferably is rhenium, molybdenum or titanium. The rapid, intense heating of the ceramic/metal/ceramic sandwiches using the defocused laser beam results in diffusive conversion of the refractory metal foil into the ceramic and in turn creates a strong bond therein.

Elotuzumab Therapy for Relapsed or Refractory Multiple Myeloma.

PubMed

Lonial, Sagar; Dimopoulos, Meletios; Palumbo, Antonio; White, Darrell; Grosicki, Sebastian; Spicka, Ivan; Walter-Croneck, Adam; Moreau, Philippe; Mateos, Maria-Victoria; Magen, Hila; Belch, Andrew; Reece, Donna; Beksac, Meral; Spencer, Andrew; Oakervee, Heather; Orlowski, Robert Z; Taniwaki, Masafumi; Röllig, Christoph; Einsele, Hermann; Wu, Ka Lung; Singhal, Anil; San-Miguel, Jesus; Matsumoto, Morio; Katz, Jessica; Bleickardt, Eric; Poulart, Valerie; Anderson, Kenneth C; Richardson, Paul

2015-08-13

Elotuzumab, an immunostimulatory monoclonal antibody targeting signaling lymphocytic activation molecule F7 (SLAMF7), showed activity in combination with lenalidomide and dexamethasone in a phase 1b-2 study in patients with relapsed or refractory multiple myeloma. In this phase 3 study, we randomly assigned patients to receive either elotuzumab plus lenalidomide and dexamethasone (elotuzumab group) or lenalidomide and dexamethasone alone (control group). Coprimary end points were progression-free survival and the overall response rate. Final results for the coprimary end points are reported on the basis of a planned interim analysis of progression-free survival. Overall, 321 patients were assigned to the elotuzumab group and 325 to the control group. After a median follow-up of 24.5 months, the rate of progression-free survival at 1 year in the elotuzumab group was 68%, as compared with 57% in the control group; at 2 years, the rates were 41% and 27%, respectively. Median progression-free survival in the elotuzumab group was 19.4 months, versus 14.9 months in the control group (hazard ratio for progression or death in the elotuzumab group, 0.70; 95% confidence interval, 0.57 to 0.85; P<0.001). The overall response rate in the elotuzumab group was 79%, versus 66% in the control group (P<0.001). Common grade 3 or 4 adverse events in the two groups were lymphocytopenia, neutropenia, fatigue, and pneumonia. Infusion reactions occurred in 33 patients (10%) in the elotuzumab group and were grade 1 or 2 in 29 patients. Patients with relapsed or refractory multiple myeloma who received a combination of elotuzumab, lenalidomide, and dexamethasone had a significant relative reduction of 30% in the risk of disease progression or death. (Funded by Bristol-Myers Squibb and AbbVie Biotherapeutics; ELOQUENT-2 ClinicalTrials.gov number, NCT01239797.).

Improved outcome of patients with relapsed/refractory Hodgkin lymphoma with a new fotemustine-based high-dose chemotherapy regimen.

PubMed

Musso, Maurizio; Messina, Giuseppe; Di Renzo, Nicola; Di Carlo, Paolo; Vitolo, Umberto; Scalone, Renato; Marcacci, Gianpaolo; Scalzulli, Potito R; Moscato, Tiziana; Matera, Rossella; Crescimanno, Alessandra; Santarone, Stella; Orciuolo, Enrico; Merenda, Anxur; Pavone, Vincenzo; Pastore, Domenico; Donnarumma, Daniela; Carella, Angelo M; Ciochetto, Chiara; Cascavilla, Nicola; Mele, Anna; Lanza, Francesco; Di Nicola, Massimo; Bonizzoni, Erminio; Pinto, Antonello

2016-01-01

High-dose chemotherapy (HDT) with autologous stem cell transplantation is the standard of care for relapsed/refractory (RR) Hodgkin lymphoma (HL). Given that HDT may cure a sizeable proportion of patients refractory to first salvage, development of newer conditioning regimens remains a priority. We present the results of a novel HDT regimen in which carmustine was substituted by a third-generation chloroethylnitrosourea, fotemustine, with improved pharmacokinetics and safety (FEAM; fotemustine, etoposide, cytarabine, melphalan) in 122 patients with RR-HL accrued into a prospective registry-based study. Application of FEAM resulted in a 2-year progression-free survival (PFS) of 73·8% [95% confidence interval (CI), 0·64-0·81] with median PFS, overall survival and time to progression yet to be reached. The 2-year risk of progression adjusted for the competitive risk of death was 19·4% (95% CI, 0·12-0·27) for the entire patient population. Most previously established independent risk factors, except for fluorodeoxyglucose ((18) (F) FDG)-uptake, were unable to predict for disease progression and survival after FEAM. Although 32% of patients had (18) (F) FDG-positrin emission tomography-positive lesions before HDT, the 2-year risk of progression adjusted for competitive risk of death was 19·4% (95% CI; 0·12-0·27). No unusual acute toxicities or early/late pulmonary adverse events were registered. FEAM emerges as an ideal HDT regimen for RR-HL patients typically pre-exposed to lung-damaging treatments. © 2015 John Wiley & Sons Ltd.

Comparison of two doses of intravenous temsirolimus in patients with relapsed/refractory mantle cell lymphoma.

PubMed

Jurczak, Wojciech; Ramanathan, Sundra; Giri, Pratyush; Romano, Alessandra; Mocikova, Heidi; Clancy, Jill; Lechuga, Mariajose; Casey, Michelle; Boni, Joseph; Giza, Agnieszka; Hess, Georg

2018-03-01

Temsirolimus 175 mg once-weekly for 3 weeks, followed by 75 mg once-weekly intravenously dosed (175/75 mg) is approved in the European Union for treatment of relapsed/refractory mantle cell lymphoma (MCL). A phase IV study explored whether similar efficacy, but improved safety could be achieved with 75 mg without 175 mg loading doses (ClinicaTrials.gov: NCT01180049). Patients with relapsed/refractory MCL were randomized to once-weekly temsirolimus 175/75 mg (n = 47) or 75 mg (n = 42). Treatment continued until objective disease progression. Primary endpoint: progression-free survival (PFS). Secondary endpoints included overall survival (OS) and adverse events (AEs). Median PFS was 4.3 versus 4.5 months (hazard ratio [HR] 0.731; 80% confidence interval [CI], 0.520-1.027), and median OS 18.7 versus 11.0 months (HR 0.681; 80% CI, 0.472-0.982) with 175/75 mg versus 75 mg. There were fewer patients with serious AEs, dose reduction, or death with 175/75 mg (57.4%, 48.9%, and 48.9%) versus 75 mg (73.8%, 64.3%, and 65.1%). Temsirolimus 175/75 mg remains the preferred dosing regimen for relapsed/refractory MCL.

Chemical evidence for differentiation, evaporation and recondensation from silicate clasts in Gujba

NASA Astrophysics Data System (ADS)

Oulton, Jonathan; Humayun, Munir; Fedkin, Alexei; Grossman, Lawrence

2016-03-01

The silicate and metal clasts in CB chondrites have been inferred to form as condensates from an impact-generated vapor plume between a metal-rich body and a silicate body. A detailed study of the condensation of impact-generated vapor plumes showed that the range of CB silicate clast compositions could not be successfully explained without invoking a chemically differentiated target. Here, we report the most comprehensive elemental study yet performed on CB silicates with 32 silicate clasts from nine slices of Gujba analyzed by laser ablation inductively coupled plasma mass spectrometry for 53 elements. Like in other studies of CBs, the silicate clasts are either barred olivine (BO) or cryptocrystalline (CC) in texture. In major elements, the Gujba silicate clasts ranged from chondritic to refractory enriched. Refractory element abundances ranged from 2 to 10 × CI, with notable anomalies in Ba, Ce, Eu, and U abundances. The two most refractory-enriched BO clasts exhibited negative Ce anomalies and were depleted in U relative to Th, characteristic of volatilization residues, while other BO clasts and the CC clasts exhibited positive Ce anomalies with excess U (1-3 × CI), and Ba (1-6 × CI) anomalies indicating re-condensation of ultra-refractory element depleted vapor. The Rare Earth Elements (REE) also exhibit light REE (LREE) enrichment or depletion in several clasts with a range of (La/Sm)CI of 0.9-1.8. This variation in the LREE is essentially impossible to accomplish by processes involving vapor-liquid or vapor-solid exchange of REE, and appears to have been inherited from a differentiated target. The most distinctive evidence for inherited chemical differentiation is observed in highly refractory element (Sc, Zr, Nb, Hf, Ta, Th) systematics. The Gujba clasts exhibit fractionations in Nb/Ta that correlate positively with Zr/Hf and span the range known from lunar and Martian basalts, and exceed the range in Zr/Hf variation known from eucrites. Variations of highly incompatible refractory elements (e.g., Th) against less incompatible elements (e.g., Zr, Sr, Sc) are not chondritic, but exhibit distinctly higher Th abundances requiring a differentiated crust to be admixed with depleted mantle in ratios that are biased to higher crust/mantle ratios than in a chondritic body. The possibility that these variations are due to admixture of refractory inclusion-debris into normal chondritic matter is raised but cannot be definitively tested because existing ;bulk; analyses of CAIs carry artifacts of unrepresentative sampling. The inferences drawn from the compositions of Gujba silicate clasts, here, complement what has been inferred from the compositions of metallic clasts, but provide surprisingly detailed insight into the structure of the target. Evidence that metal and silicate in CB chondrites both formed from impact-generated vapor plumes, taken together with recent work on metallic nodules in E chondrites, and on ordinary chondrites, indicates that chondrule formation occurs by this mechanism quite widely. However, the nature of the impact on the CB body is quite different than the popular conceptions of impact of partially or wholly molten chondritic bodies and the younger (5 Ma) age of CB chondrules is consistent with origin in a disk with more evolved targets and impactors gravitationally perturbed by nascent planets.

Numerical evaluation of the laser-pulse modification modes of the metal surface layer in the presence of a surface-active component in the melt

NASA Astrophysics Data System (ADS)

Popov, V. N.; Cherepanov, A. N.

2017-09-01

Numerical evaluation of the laser-pulse modification of a metal layer with refractory nano-size particles was done. The modes of the laser-pulse action promoting creation of the flows for homogeneous distribution of modifying particles in the melt were determined for various amounts of the surface-active admixture in the metal.

Burner systems

DOEpatents

Doherty, Brian J.

1984-07-10

A burner system particularly useful for downhole deployment includes a tubular combustion chamber unit housed within a tubular coolant jacket assembly. The combustion chamber unit includes a monolithic tube of refractory material whose inner surface defines the combustion zone. A metal reinforcing sleeve surrounds and extends the length of the refractory tube. The inner surface of the coolant jacket assembly and outer surface of the combustion chamber unit are dimensioned so that those surfaces are close to one another in standby condition so that the combustion chamber unit has limited freedom to expand with that expansion being stabilized by the coolant jacket assembly so that compression forces in the refractory tube do not exceed about one-half the safe compressive stress of the material; and the materials of the combustion chamber unit are selected to establish thermal gradient parameters across the combustion chamber unit to maintain the refractory tube in compression during combustion system start up and cool down sequences.

CASTING SLIPS FOR FABRICATION OF REFRACTORY METAL WARE

DOEpatents

Stoddard, S.D.; Nuckolls, D.E.; Cowan, R.E.

1962-09-01

A composition is given for slip casting tungsten metal. The composition consists essentially of tungsten metal with an average particle size of 0.9 micron, an organic vehicle such as methyl chloroform, o-xylene, n-butyl acetate, isobutyl acetate, and 1, 1, 2, 2-tetrachlorethane, and a suspending agent such as ethyl cellulose, with the approximate ratio of said vehicle to the tungsten metal being 12 cc of a solution containing from 5 to about 20 grams of said ethyl cellulose in 400 cc of said organic vehicle per 100 grams of metal. (AEC)

Hydrogen-isotope permeation barrier

DOEpatents

Maroni, Victor A.; Van Deventer, Erven H.

1977-01-01

A composite including a plurality of metal layers has a Cu-Al-Fe bronze layer and at least one outer layer of a heat and corrosion resistant metal alloy. The bronze layer is ordinarily intermediate two outer layers of metal such as austenitic stainless steel, nickel alloys or alloys of the refractory metals. The composite provides a barrier to hydrogen isotopes, particularly tritium that can reduce permeation by at least about 30 fold and possibly more below permeation through equal thicknesses of the outer layer material.

Dynamic polarizability of tungsten atoms reconstructed from fast electrical explosion of fine wires in vacuum

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sarkisov, G. S.; Rosenthal, S. E.; Struve, K. W.

For nanosecond electrical explosion of fine metal wires in vacuum generates calibrated, radially expanded gas cylinders of metal atoms are surrounded by low-density fast expanding plasma corona. Here, a novel integrated-phase technique, based on laser interferometry, provides the dynamic dipole polarizability of metal atoms. This data was previously unavailable for tungsten atoms. Furthermore, an extremely high melting temperature and significant pre-melt electronic emission make these measurements particularly complicated for this refractory metal.

Dynamic polarizability of tungsten atoms reconstructed from fast electrical explosion of fine wires in vacuum

DOE PAGES

Sarkisov, G. S.; Rosenthal, S. E.; Struve, K. W.

2016-10-12

For nanosecond electrical explosion of fine metal wires in vacuum generates calibrated, radially expanded gas cylinders of metal atoms are surrounded by low-density fast expanding plasma corona. Here, a novel integrated-phase technique, based on laser interferometry, provides the dynamic dipole polarizability of metal atoms. This data was previously unavailable for tungsten atoms. Furthermore, an extremely high melting temperature and significant pre-melt electronic emission make these measurements particularly complicated for this refractory metal.

Self-Expandable Metal Stents for Persisting Esophageal Variceal Bleeding after Band Ligation or Injection-Therapy: A Retrospective Study.

PubMed

Müller, Martin; Seufferlein, Thomas; Perkhofer, Lukas; Wagner, Martin; Kleger, Alexander

2015-01-01

Despite a pronounced reduction of lethality rates due to upper gastrointestinal bleeding, esophageal variceal bleeding remains a challenge for the endoscopist and still accounts for a mortality rate of up to 40% within the first 6 weeks. A relevant proportion of patients with esophageal variceal bleeding remains refractory to standard therapy, thus making a call for additional tools to achieve hemostasis. Self-expandable metal stents (SEMS) incorporate such a tool. We evaluated a total number of 582 patients admitted to our endoscopy unit with the diagnosis "gastrointestinal bleeding" according to our documentation software between 2011 and 2014. 82 patients suffered from esophageal variceal bleeding, out of which 11 cases were refractory to standard therapy leading to SEMS application. Patients with esophageal malignancy, fistula, or stricture and a non-esophageal variceal bleeding source were excluded from the analysis. A retrospective analysis reporting a series of clinically relevant parameters in combination with bleeding control rates and adverse events was performed. The initial bleeding control rate after SEMS application was 100%. Despite this success, we observed a 27% mortality rate within the first 42 days. All of these patients died due to non-directly hemorrhage-associated reasons. The majority of patients exhibited an extensive demand of medical care with prolonged hospital stay. Common complications were hepatic decompensation, pulmonary infection and decline of renal function. Interestingly, we found in 7 out of 11 patients (63.6%) stent dislocation at time of control endoscopy 24 h after hemostasis or at time of stent removal. The presence of hiatal hernia did not affect obviously stent dislocation rates. Refractory patients had significantly longer hospitalization times compared to non-refractory patients. Self-expandable metal stents for esophageal variceal bleeding seem to be safe and efficient after failed standard therapy. Stent migration appeared to be a common incident that did not lead to reactivation of bleeding in any of our patients. SEMS should be considered a reasonable treatment option for refractory esophageal variceal bleeding after treatment failure of ligature and sclerotherapy and non-availability of or contraindication for other measures (e.g. TIPS).

The cathode material for a plasma-arc heater

NASA Astrophysics Data System (ADS)

Yelyutin, A. V.; Berlin, I. K.; Averyanov, V. V.; Kadyshevskii, V. S.; Savchenko, A. A.; Putintseva, R. G.

1983-11-01

The cathode of a plasma arc heater experiences a large thermal load. The temperature of its working surface, which is in contact with the plasma, reaches high values, as a result of which the electrode material is subject to erosion. Refractory metals are usually employed for the cathode material, but because of the severe erosion do not usually have a long working life. The most important electrophysical characteristic of the electrode is the electron work function. The use of materials with a low electron work function allows a decrease in the heat flow to the cathode, and this leads to an increase in its erosion resistance and working life. The electroerosion of certain materials employed for the cathode in an electric arc plasma generator in the process of reduction smelting of refractory metals was studied.

Gas atomization synthesis of refractory or intermetallic compounds and supersaturated solid solutions

DOEpatents

Anderson, I.E.; Lograsso, B.K.; Ellis, T.W.

1994-11-29

A metallic melt is atomized using a high pressure atomizing gas wherein the temperature of the melt and the composition of the atomizing gas are selected such that the gas and melt react in the atomization spray zone to form a refractory or intermetallic compound in the as-atomized powder particles. A metallic melt is also atomized using a high pressure atomizing gas mixture gas wherein the temperature of the melt and the ratio of a reactive gas to a carrier gas are selected to form powder particles comprising a supersaturated solid solution of the atomic species of the reactive gas in the particles. The powder particles are then heat treated to precipitate dispersoids in-situ therein to form a dispersion strengthened material. 9 figures.

Magnesium fluoride as energy storage medium for spacecraft solar thermal power systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lurio, C.A.

1992-10-01

MgF2 was investigated as a phase-change energy-storage material for LEO power systems using solar heat to run thermal cycles. It provides a high heat of fusion per unit mass at a high melting point (1536 K). Theoretical evaluation showed the basic chemical compatibility of liquid MgF2 with refractory metals at 1600 K, though transient high pressures of H2 can occur in a closed container due to reaction with residual moisture. The compatibility was tested in two refractory metal containers for over 2000 h. Some showed no deterioration, while there was evidence that the fluoride reacted with hafnium in others. Corollarymore » tests showed that the MgF2 supercooled by 10-30 K and 50-90 K. 24 refs.« less

Feasibility of EB Welded Hastelloy X and Combination of Refractory Metals

NASA Technical Reports Server (NTRS)

Martinez, Diana A.

2004-01-01

As NASA continues to expand its horizon, exploration and discovery creates the need of advancement in technology. The Jupiter Icy Moon Orbiter's (JIMO) mission to explore and document the outer surfaces, rate the possibility of holding potential life forms, etc. within the three moons (Callisto, Ganymede, and Europa) proves to be challenging. The orbiter itself consists of many sections including: the nuclear reactor and the power conversion system, the radiator panels, and the thrusters and antenna. The nuclear reactor serves as a power source, and if successfully developed, can operate for extended periods. During the duration of my tenure at NASA Glenn Research Center's (NASA GRC) Advanced Metallics Branch, I was assigned to assist Frank J. Ritzert on analyzing the feasibility of the Electron Beam Welded Hastelloy X (HX), a nickel-based superalloy, to Niobium- 1 %Zirconium (Nb-1 Zr) and other refractory metals/alloys including Tantalum, Molybdenum, Tungsten, and Rhenium alloys. This welding technique is going to be used for the nuclear reactor within JIMO.

Refractory testicular germ cell tumors are highly sensitive to the second generation DNA methylation inhibitor guadecitabine.

PubMed

Albany, Costantine; Hever-Jardine, Mary P; von Herrmann, Katherine M; Yim, Christina Y; Tam, Janice; Warzecha, Joshua M; Shin, Leah; Bock, Sarah E; Curran, Brian S; Chaudhry, Aneeq S; Kim, Fred; Sandusky, George E; Taverna, Pietro; Freemantle, Sarah J; Christensen, Brock C; Einhorn, Lawrence H; Spinella, Michael J

2017-01-10

Testicular germ cell tumors (TGCTs) are the most common cancers of young males. A substantial portion of TGCT patients are refractory to cisplatin. There are no effective therapies for these patients, many of whom die from progressive disease. Embryonal carcinoma (EC) are the stem cells of TGCTs. In prior in vitro studies we found that EC cells were highly sensitive to the DNA methyltransferase inhibitor, 5-aza deoxycytidine (5-aza). Here, as an initial step in bringing demethylation therapy to the clinic for TGCT patients, we evaluated the effects of the clinically optimized, second generation demethylating agent guadecitabine (SGI-110) on EC cells in an animal model of cisplatin refractory testicular cancer. EC cells were exquisitely sensitive to guadecitabine and the hypersensitivity was dependent on high levels of DNA methyltransferase 3B. Guadecitabine mediated transcriptional reprogramming of EC cells included induction of p53 targets and repression of pluripotency genes. As a single agent, guadecitabine completely abolished progression and induced complete regression of cisplatin resistant EC xenografts even at doses well below those required to impact somatic solid tumors. Low dose guadecitabine also sensitized refractory EC cells to cisplatin in vivo. Genome-wide analysis indicated that in vivo antitumor activity was associated with activation of p53 and immune-related pathways and the antitumor effects of guadecitabine were dependent on p53, a gene rarely mutated in TGCTs. These preclinical findings suggest that guadecitabine alone or in combination with cisplatin is a promising strategy to treat refractory TGCT patients.

Experimental investigation of refractory metals in the premelting region during fast heating

NASA Astrophysics Data System (ADS)

Senchenko, V. N.; Belikov, R. S.; Popov, V. S.

2015-11-01

This work demonstrates experimental possibility of investigation of high refractory materials around its melting point, particularly in premelting region with high accuracy. In this article authors describe the developed experimental setup based on rapid resistive self-heating of a sample by a large current pulse generated by a capacitor discharge circuit that allow fast pulse interruption by temperature feedback signal. The sample temperature was measured with a two-channel microsecond radiation pyrometer. Preliminary experiments were conducted on tantalum and molybdenum at heating speed of 108 K/s. The method allows investigating thermophysical properties of refractory conductive materials such as melting temperature, melting heat, specific resistivity, specific enthalpy and specific heat capacity in solid and liquid phase, especially in premelting area.

Results of a Pivotal Phase II Study of Brentuximab Vedotin for Patients With Relapsed or Refractory Hodgkin's Lymphoma

PubMed Central

Younes, Anas; Gopal, Ajay K.; Smith, Scott E.; Ansell, Stephen M.; Rosenblatt, Joseph D.; Savage, Kerry J.; Ramchandren, Radhakrishnan; Bartlett, Nancy L.; Cheson, Bruce D.; de Vos, Sven; Forero-Torres, Andres; Moskowitz, Craig H.; Connors, Joseph M.; Engert, Andreas; Larsen, Emily K.; Kennedy, Dana A.; Sievers, Eric L.; Chen, Robert

2012-01-01

Purpose Brentuximab vedotin is an antibody-drug conjugate (ADC) that selectively delivers monomethyl auristatin E, an antimicrotubule agent, into CD30-expressing cells. In phase I studies, brentuximab vedotin demonstrated significant activity with a favorable safety profile in patients with relapsed or refractory CD30-positive lymphomas. Patients and Methods In this multinational, open-label, phase II study, the efficacy and safety of brentuximab vedotin were evaluated in patients with relapsed or refractory Hodgkin's lymphoma (HL) after autologous stem-cell transplantation (auto-SCT). Patients had histologically documented CD30-positive HL by central pathology review. A total of 102 patients were treated with brentuximab vedotin 1.8 mg/kg by intravenous infusion every 3 weeks. In the absence of disease progression or prohibitive toxicity, patients received a maximum of 16 cycles. The primary end point was the overall objective response rate (ORR) determined by an independent radiology review facility. Results The ORR was 75% with complete remission (CR) in 34% of patients. The median progression-free survival time for all patients was 5.6 months, and the median duration of response for those in CR was 20.5 months. After a median observation time of more than 1.5 years, 31 patients were alive and free of documented progressive disease. The most common treatment-related adverse events were peripheral sensory neuropathy, nausea, fatigue, neutropenia, and diarrhea. Conclusion The ADC brentuximab vedotin was associated with manageable toxicity and induced objective responses in 75% of patients with relapsed or refractory HL after auto-SCT. Durable CRs approaching 2 years were observed, supporting study in earlier lines of therapy. PMID:22454421

A phase II study of high-dose celecoxib and metronomic 'low-dose' cyclophosphamide and methotrexate in patients with relapsed and refractory lymphoma.

PubMed

El Bary, Naser Abd; Hashem, Tarek; Metwally, Hasan; Ghany, Ashraf Abd; El Mageed, Hager Abd

2010-01-01

Relapsed, histologically aggressive non-Hodgkin lymphoma (NHL) has a poor prognosis; relapsed patients who do not respond to second line therapy or are unfit for BMT have a worse prognosis. Angiogenesis is increased in aggressive NHL and could be targeted by selective cyclooxygenase-2 inhibition and metronomic chemotherapy. We assessed the toxicity of metronomic chemotherapy and the response and progression-free survival in patients with relapsed/refractory diffuse large B-cell lymphoma (DLBCL). We prospectively studied 41 patients with a diagnosis of relapsed and/or refractory DLBCL who may have received any number of preceding therapies (as long as one included an anthracycline) and were not candidates for bone marrow transplantation. They received oral cyclophosphamide (50 mg every day), oral methotrexate (2.5 mg 4 times/week) and high-dose oral celecoxib (400 mg twice daily) until there was disease progression or unacceptable toxicity. All 41 patients (median age, 56 years) were evaluable for toxicity and response, with a median follow up of 9.1 months (range, 4-35 months). At relapse, 51.2% had a high international prognostic index. The treatment protocol was well tolerated with no major toxicities. The most common toxicities were fatigue (61%), nausea (22%), neutropenia (19.5%), and anemia (22%). In 31.7% there was a partial response and 48.8% had stable disease. Progression-free survival was 12 months. The median response duration was 10 months. We conclude that metronomic chemotherapy can be used for patients with relapsed and or refractory DLBCL with reasonable outcome and acceptable toxicity. Standard approaches such as hematopoietic stem cell transplantation and chemo-immunotherapy combinations should be explored prior to a decision on metronomic chemotherapy.

Protocol Design for the Bench to Bed Trial in Alectinib-Refractory Non-Small-Cell Lung Cancer Patients Harboring the EML4-ALK Fusion Gene (ALRIGHT/OLCSG1405).

PubMed

Isozaki, Hideko; Hotta, Katsuyuki; Ichihara, Eiki; Takigawa, Nagio; Ohashi, Kadoaki; Kubo, Toshio; Ninomiya, Takashi; Ninomiya, Kiichiro; Oda, Naohiro; Yoshioka, Hiroshige; Ichikawa, Hirohisa; Inoue, Masaaki; Takata, Ichiro; Shibayama, Takuo; Kuyama, Shoichi; Sugimoto, Keisuke; Harada, Daijiro; Harita, Shingo; Sendo, Toshiaki; Tanimoto, Mitsune; Kiura, Katsuyuki

2016-11-01

Based on our preclinical study results, which showed that the activation of the hepatocyte growth factor/MET pathway is a potential mechanism of acquired resistance to alectinib, we launched the ALRIGHT (OLCSG1405 [alectinib-refractory non-small-cell lung cancer patients harboring the EML4-ALK fusion gene]), a phase II trial of the anaplastic lymphoma kinase (ALK)/MET inhibitor crizotinib in patients with non-small-cell lung cancer refractory to alectinib and harboring the echinoderm microtubule-associated protein-like 4 (EML4)-ALK fusion gene. Patients with ALK-rearranged tumors who have developed disease progression during alectinib treatment will receive crizotinib monotherapy until disease progression or the occurrence of unacceptable toxicity. The primary endpoint is set as the objective response rate, assuming that a response in 50% of eligible patients will indicate potential usefulness and that 15% would be the lower limit of interest (1-sided α of 0.05, β of 0.20). The estimated accrual number of patients is 9. The secondary endpoints include progression-free survival, overall survival, adverse events, and patient-reported outcomes. We will also take tissue samples before crizotinib monotherapy to conduct an exploratory analysis of ALK and hepatocyte growth factor/MET expression levels and gene alterations (eg, mutations, amplifications, and translocations). We will obtain information regarding whether crizotinib, which targets not only ALK, but also MET, can truly produce efficacy with acceptable safety profiles in ALK + non-small-cell lung cancer even in the alectinib-refractory setting. Copyright © 2016 Elsevier Inc. All rights reserved.

Total-Body Irradiation and Fludarabine Phosphate Followed by Donor Peripheral Blood Stem Cell Transplant in Treating Patients With Hematologic Malignancies or Kidney Cancer

ClinicalTrials.gov

2017-12-11

Adult Acute Myeloid Leukemia in Remission; Childhood Acute Lymphoblastic Leukemia in Remission; Childhood Acute Myeloid Leukemia in Remission; Childhood Myelodysplastic Syndrome; Childhood Renal Cell Carcinoma; Chronic Myelomonocytic Leukemia; Clear Cell Renal Cell Carcinoma; de Novo Myelodysplastic Syndrome; Metastatic Renal Cell Cancer; Previously Treated Myelodysplastic Syndrome; Progression of Multiple Myeloma or Plasma Cell Leukemia; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Acute Myeloid Leukemia; Recurrent Adult Hodgkin Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Adult Non-Hodgkin Lymphoma; Recurrent Childhood Acute Lymphoblastic Leukemia; Recurrent Childhood Acute Myeloid Leukemia; Recurrent Childhood Lymphoblastic Lymphoma; Recurrent Childhood Non-Hodgkin Lymphoma; Refractory Anemia; Refractory Anemia With Ringed Sideroblasts; Refractory Childhood Hodgkin Lymphoma; Refractory Chronic Lymphocytic Leukemia; Renal Medullary Carcinoma; Type 1 Papillary Renal Cell Carcinoma; Type 2 Papillary Renal Cell Carcinoma; Untreated Adult Acute Lymphoblastic Leukemia; Untreated Adult Acute Myeloid Leukemia; Untreated Childhood Acute Lymphoblastic Leukemia

Functional profiles of orphan membrane transporters in the life cycle of the malaria parasite

PubMed Central

Kenthirapalan, Sanketha; Waters, Andrew P.; Matuschewski, Kai; Kooij, Taco W. A.

2016-01-01

Assigning function to orphan membrane transport proteins and prioritizing candidates for detailed biochemical characterization remain fundamental challenges and are particularly important for medically relevant pathogens, such as malaria parasites. Here we present a comprehensive genetic analysis of 35 orphan transport proteins of Plasmodium berghei during its life cycle in mice and Anopheles mosquitoes. Six genes, including four candidate aminophospholipid transporters, are refractory to gene deletion, indicative of essential functions. We generate and phenotypically characterize 29 mutant strains with deletions of individual transporter genes. Whereas seven genes appear to be dispensable under the experimental conditions tested, deletion of any of the 22 other genes leads to specific defects in life cycle progression in vivo and/or host transition. Our study provides growing support for a potential link between heavy metal homeostasis and host switching and reveals potential targets for rational design of new intervention strategies against malaria. PMID:26796412

[State of the art treatment of progressive or refractory multiple myeloma].

PubMed

Schmidt-Wolf, I G H; Straka, C; Scheid, C; Einsele, H; Goldschmidt, H; Engelhardt, M

2014-10-01

Multiple myeloma (MM) is with an incidence of 4-6/100 000 inhabitants a fairly frequent malignancy of B cells. The incidence increases markedly with age. In this review changes in the treatment of relapsed / refractory myeloma during the last decade have been analysed. The present standard of care in the progressive or refractory myeloma was elaborated by the working group "Refractory Multiple Myeloma" using an extensive literature search for studies published between 2003 and 2013. Outside of clinical trials, high-dose therapy with stem cell transplantation is recommended in fit patients up to 75 years without significant comorbidities. Ongoing studies address the question about the least toxic and the most effective treatment. Therefore, inclusion of patients in therapeutic trials and use of novel agent combinations is highly recommended, e.g. with 3(rd) generation-IMIDs (pomalidomide), new proteasome inhibitors, such as carfilzomib, ixazomib or oprozomib, antibodies, such as elotuzumab, daratumumab or SAR650984, siltuximab, tabalumab, denosumab, romosozumab, BTK-, HSP-inhibitors and other innovative phase I/II agents. Based on new insights in the pathogenesis of the disease, treatment options for MM have changed significantly in recent years. There is a significantly larger treatment diversity, i.e. more MM-active agents and combinations are available today. Even with relapsed MM, patients with the disease often live longer and have fewer complications. © Georg Thieme Verlag KG Stuttgart · New York.

Simplified thermochemistry of oxygen in lithium and sodium for liquid metal cooling systems

NASA Technical Reports Server (NTRS)

Tower, L. K.

1972-01-01

Plots of oxygen chemical potential against composition of lithium-oxygen solutions and sodium-oxygen solutions for a range of temperature were constructed. For each liquid metal two such plots were prepared. For one plot ideal solution behavior was assumed. For the other plot, existing solubility limit data for oxygen in the liquid metal were used to determine a first-order term for departure from ideality. The use of the plots in evaluating the oxygen gettering capability of refractory metals in liquid metal cooling systems is illustrated by a simple example involving lithium, oxygen, and hafnium.

Zeolite-based SCR catalysts and their use in diesel engine emission treatment

DOEpatents

Narula, Chaitanya K.; Yang, Xiaofan

2016-08-02

A catalyst comprising a zeolite loaded with copper ions and at least one trivalent metal ion other than Al.sup.+3, wherein the catalyst decreases NO.sub.x emissions in diesel exhaust. The trivalent metal ions are selected from, for example, trivalent transition metal ions, trivalent main group metal ions, and/or trivalent lanthanide metal ions. In particular embodiments, the catalysts are selected from Cu--Fe-ZSM5, Cu--La-ZSM-5, Fe--Cu--La-ZSM5, Cu--Sc-ZSM-5, and Cu--In-ZSM5. The catalysts are placed on refractory support materials and incorporated into catalytic converters.

Zeolite-based SCR catalysts and their use in diesel engine emission treatment

DOEpatents

Narula, Chaitanya K; Yang, Xiaofan

2015-03-24

A catalyst comprising a zeolite loaded with copper ions and at least one trivalent metal ion other than Al.sup.+3, wherein the catalyst decreases NO.sub.x emissions in diesel exhaust. The trivalent metal ions are selected from, for example, trivalent transition metal ions, trivalent main group metal ions, and/or trivalent lanthanide metal ions. In particular embodiments, the catalysts are selected from Cu--Fe-ZSM5, Cu--La-ZSM-5, Fe--Cu--La-ZSM5, Cu--Sc-ZSM-5, and Cu--In-ZSM5. The catalysts are placed on refractory support materials and incorporated into catalytic converters.

Refractoriness to immunochemotherapy in follicular lymphoma: Predictive factors and outcome.

PubMed

Sorigue, Marc; Mercadal, Santiago; Alonso, Sara; Fernández-Álvarez, Ruben; García, Olga; Moreno, Miriam; Pomares, Helena; Alcoceba, Miguel; González-García, Esther; Motlló, Cristina; González-Barca, Eva; Martin, Alejandro; Sureda, Anna; Caballero, Dolores; Ribera, Josep-María; Sancho, Juan-Manuel

2017-12-01

Follicular lymphoma is characterized by a good response to immunochemotherapy (ICT). However, a small percentage of patients responds poorly to treatment and seems to have a worse outcome. This study attempted to identify the predictive factors and outcome of refractoriness to first-line ICT. All patients diagnosed with stage II to IV follicular lymphoma between 2002 and 2014 and treated with first-line ICT in 4 Spanish institutions were analyzed. Those with no response or progression or relapse within 6 months of first-line response assessment were considered ICT refractory. Three hundred forty-three patients were included (median age 58 years, 48% male), of whom 53 (15%) were ICT refractory. On multivariate analysis, high-risk follicular lymphoma international prognostic index (FLIPI) score, B symptoms, and elevated β2-microglobulin were correlated with refractoriness, and refractoriness, high-risk FLIPI score, and β2-microglobulin were correlated with overall survival (OS). Compared with ICT-sensitive, ICT-refractory patients had a higher incidence of histological transformation (5-year cumulative incidence 25% [14%-39%] vs. 6% [3%-10%], P < .001), a higher rate of refractoriness to second-line therapy (16/33 [48%] vs. 13/57 [23%], P = .01), and a lower OS (5-year OS probability 38% [95% CI 23%-53%] vs. 87% [82%-92%%], P < .001). In conclusion, refractoriness to ICT was seen in 15% of patients and was predicted by high-FLIPI scores, B symptoms, and elevated serum β2-micrglobulin. Immunochemotherapy-refractory patients had a worse prognosis than ICT-sensitive patients, and current treatment options for this subgroup are not satisfactory. Copyright © 2017 John Wiley & Sons, Ltd.

Transpiration-Cooled Spacecraft-Insulation-Repair Fasteners

NASA Technical Reports Server (NTRS)

Camarda, Charles J.; Pettit, Donald R.; Glass, David; Scotti, Stephen J.; Vaughn, Wallace Lee; Rawal, Suraj

2012-01-01

Transpiration-cooled fasteners are proposed that operate like an open-loop heat pipe (self-tapping screws, bolts, and spikes) for use in on-orbit repair of thermal- insulation of a space shuttle or other spacecraft. By limiting the temperature rise of such a fastener and of the adjacent repair material and thermal protection system, the transpiration cooling would contribute to the ability of the repair to retain its strength and integrity in the high-heat-flux, oxidizing environment of reentry into the atmosphere of the Earth. A typical fastener according to the proposal would include a hollow refractory-metal, refractory-composite, or ceramic screw or bolt, the central cavity of which would be occupied by a porous refractory- metal or ceramic plug that would act as both a reservoir and a wick for a transpirant liquid. The plug dimensions, the plug material, and the sizes of the pores would be chosen in conjunction with the transpirant liquid so that (1) capillary pumping could be relied upon to transport the liquid to the heated surface, where the liquid would be vaporized, and (2) the amount of liquid would suffice for protecting against the anticipated heat flux and integrated heat load.

Synthesis and Characterization of YB4 Ceramics

DTIC Science & Technology

2011-06-24

capa bility at temperatures above 2000°C1 with adequate mechani cal properties and oxidation resistance. Refractory metal borides based on HfB2 and ZrB2...increase in the oxidation resistance was accomplished by the addition of the Group IV VI transition metal borides , which was the result of phase...metal borides for use as materials for ultra high temper ature (UHT) applications. However, for instance, yttrium tet raboride, YB4, appears promising as

Recovery of Nickel from Nickel-Based Superalloy Scraps by Utilizing Molten Zinc

NASA Astrophysics Data System (ADS)

Yagi, Ryohei; Okabe, Toru H.

2017-02-01

With the purpose of developing a new process for recycling nickel (Ni) directly from superalloy scraps, a fundamental study on the extraction and separation of Ni was carried out using molten zinc (Zn) as the extraction medium. In order to examine the reaction between molten Zn and the Ni-based superalloy, superalloy samples and Zn shots were heated at 1173 K (900 °C) for 6 hours. After heating, the superalloy samples fully reacted with Zn and dissolved in molten Zn. The Zn-alloyed sample obtained by slow cooling consisted of two separated upper and lower phases. In the upper part of the sample, only Zn and the Zn-Ni alloys were found; in the lower part, an intermetallic alloy consisting of refractory metals such as rhenium (Re) and tantalum (Ta) was found. This result shows that Ni and refractory metals contained in the scrap can be separated by utilizing the density differences between the Zn-Ni alloy and the refractory metals in molten Zn. Vacuum treatment of the upper part of the Zn-alloyed sample at 1173 K (900 °C) reduced the concentration of Zn in the sample from 97.0 to 0.4 mass pct. After Zn removal, a Ni alloy containing Ni with a purity of 85.3 to 86.1 mass pct and negligible quantities (<0.1 mass pct) of Re and Ta was obtained. Moreover, recovered Zn metal after distillation had a purity of more than 99.9 mass pct. Therefore, this process could be an environmentally sound recycling process that can recover Ni from superalloy scraps without the consumption of Zn or the generation of toxic wastes solutions.

Chemical plating method of preparing radiation source material

DOEpatents

Smith, P.K.; Huntoon, R.T.; Mosley, W.C. Jr.

1973-12-11

A uniform dispersion of a radioisotope within a noble metal matrix is provided by chemically plating a noble metal coating onto particles including a dissociable compound of the mdioisotope. A suspension of the dissociable compound in a chemically reductive solution is prepared and noble metal cations added to produce the noble metal coatings. The coated particles are filtered, dried and heated to calcine the dissociable compound to a refractory powder. The powder can be encapsulated in measured portions or consolidated and shaped into an elongated form for easy apportionnnent as radiation source material. (Official Gazette)

Method of forming impermeable carbide coats on graphite

DOEpatents

Wohlberg, C.

1973-12-11

A method of forming an impermeable refractory metal carbide coating on graphite is described in which a metal containing oxidant and a carbide former are applied to the surface of the graphite, heated to a temperature of between 1200 and 1500 deg C in an inert gas, under a vacuum and continuing to heat to about 2300 deg C. (Official Gazette)

Electron-Beam Atomic Spectroscopy for In Situ Measurements of Melt Composition for Refractory Metals: Analysis of Fundamental Physics and Plasma Models

NASA Astrophysics Data System (ADS)

Gasper, Paul Joseph; Apelian, Diran

2015-04-01

Electron-beam (EB) melting is used for the processing of refractory metals, such as Ta, Nb, Mo, and W. These metals have high value and are critical to many industries, including the semiconductor, aerospace, and nuclear industries. EB melting can also purify secondary feedstock, enabling the recovery and recycling of these materials. Currently, there is no method for measuring melt composition in situ during EB melting. Optical emission spectroscopy of the plasma generated by EB impact with vapor above the melt, a technique here termed electron-beam atomic spectroscopy, can be used to measure melt composition in situ, allowing for analysis of melt dynamics, facilitating improvement of EB melting processes and aiding recycling and recovery of these critical and high-value metals. This paper reviews the physics of the plasma generation by EB impact by characterizing the densities and energies of electrons, ions, and neutrals, and describing the interactions between them. Then several plasma models are introduced and their suitability to this application analyzed. Lastly, a potential method for calibration-free composition measurement is described and the challenges for implementation addressed.

40 CFR 62.1500 - Identification of Plan.

Code of Federal Regulations, 2010 CFR

2010-07-01

... mercury emission standards, and shutdown provisions for mass burn refractory MWC units. (3) Revision to... FR 63313, Dec. 6, 2001; 70 FR 9229, Feb. 25, 2005] Metals, Acid Gases, Organic Compounds and Nitrogen...

40 CFR 442.2 - General definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., organic chemicals including: alcohols, aldehydes, formaldehydes, phenols, peroxides, organic salts, amines, amides, other nitrogen compounds, other aromatic compounds, aliphatic organic chemicals, glycols, glycerines, and organic polymers; refractory organic compounds including: ketones, nitriles, organo-metallic...

Analysis of renal impairment in MM-003, a phase III study of pomalidomide + low - dose dexamethasone versus high - dose dexamethasone in refractory or relapsed and refractory multiple myeloma

PubMed Central

Weisel, Katja C.; Dimopoulos, Meletios A.; Moreau, Philippe; Lacy, Martha Q.; Song, Kevin W.; Delforge, Michel; Karlin, Lionel; Goldschmidt, Hartmut; Banos, Anne; Oriol, Albert; Alegre, Adrian; Chen, Christine; Cavo, Michele; Garderet, Laurent; Ivanova, Valentina; Martinez-Lopez, Joaquin; Knop, Stefan; Yu, Xin; Hong, Kevin; Sternas, Lars; Jacques, Christian; Zaki, Mohamed H.; Miguel, Jesus San

2016-01-01

Pomalidomide + low-dose dexamethasone is effective and well tolerated for refractory or relapsed and refractory multiple myeloma after bortezomib and lenalidomide failure. The phase III trial MM-003 compared pomalidomide + low-dose dexamethasone with high-dose dexamethasone. This subanalysis grouped patients by baseline creatinine clearance ≥ 30 − < 60 mL/min (n=93, pomalidomide + low-dose dexamethasone; n=56, high-dose dexamethasone) or ≥ 60 mL/min (n=205, pomalidomide + low-dose dexamethasone; n=93, high-dose dexamethasone). Median progression-free survival was similar for both subgroups and favored pomalidomide + low-dose dexamethasone versus high-dose dexamethasone: 4.0 versus 1.9 months in the group with baseline creatinine clearance ≥ 30 − < 60 mL/min (P<0.001) and 4.0 versus 2.0 months in the group with baseline creatinine clearance ≥ 60 mL/min (P<0.001). Median overall survival for pomalidomide + low-dose dexamethasone versus high-dose dexamethasone was 10.4 versus 4.9 months (P=0.030) and 15.5 versus 9.2 months (P=0.133), respectively. Improved renal function, defined as an increase in creatinine clearance from < 60 to ≥ 60 mL/min, was similar in pomalidomide + low-dose dexamethasone and high-dose dexamethasone patients (42% and 47%, respectively). Improvement in progression-free and overall survival in these patients was comparable with that in patients without renal impairment. There was no increase in discontinuations of therapy, dose modifications, and adverse events in patients with moderate renal impairment. Pomalidomide at a starting dose of 4 mg + low-dose dexamethasone is well tolerated in patients with refractory or relapsed and refractory multiple myeloma, and of comparable efficacy if moderate renal impairment is present. This trial was registered with clinicaltrials.gov identifier 01311687 and EudraCT identifier 2010-019820-30. PMID:27081177

Replacing critical and strategic refractory metal elements in nickel-base superalloys. [NASA's COSAM program

NASA Technical Reports Server (NTRS)

Stephens, J. R.; Dreshfield, R. L.; Nathal, M. V.

1983-01-01

Because of the import status and essential nature of their use, cobalt, chromium, tantalum, and niobium were identified as strategic and critical in the aerospace industry. NASA's Conservation of Strategic Aerospace Materials (COSAM) program aims to reduce the need for strategic materials used in gas turbine engines. Technological thrusts in two major areas are under way to meet the primary objective of conserving the use of strategic materials in nickelbase superalloys. These thrusts consist of strategic element substitution and alternative material identification. The program emphasizes cooperative research teams involving NASA Lewis Research Center, universities, and industry. The adoption of refractory metals in nickel-base superalloys is summarized including their roles in mechanical strengthening and environmental resistance; current research activities under way in the COSAM Program are presented as well as research findings to date.

Adherence of sputtered titanium carbides

NASA Technical Reports Server (NTRS)

Brainard, W. A.; Wheeler, D. R.

1979-01-01

The study searches for interface treatment that would increase the adhesion of TiC coating to nickel- and titanium-base alloys. Rene 41 (19 wt percent Cr, 11 wt percent Mo, 3 wt percent Ti, balance Ni) and Ti-6Al-4V (6 wt percent Al, 4 wt percent V, balance Ti) are considered. Adhesion of the coatings is evaluated in pin-and disk friction tests. The coatings and interface regions are examined by X-ray photoelectron spectroscopy. Results suggest that sputtered refractory compound coatings adhere best when a mixed compound of coating and substrate metals is formed in the interfacial region. The most effective type of refractory compound interface appears to depend on both substrate and coating material. A combination of metallic interlayer deposition and mixed compound interface formation may be more effective for some substrate coating combinations than either alone.

Atomization from a tantalum surface in graphite furnace atomic absorption spectrometry

NASA Astrophysics Data System (ADS)

Gregoire, D. C.; Chakrabarti, C. L.

The mechanism of atom formation of U, V, Mo, Ni, Mn, Cu and Mg atomized from pyrolytic graphite and tantalum metal surfaces has been studied. The mechanism of atom formation for U from a graphite tube atomizer is reported for the first time. The peak absorbance for U and Cu is increased by factors of 59.7 and 2.0, respectively, whereas that of V, Mo and Ni is reduced by several orders of magnitude when they are atomized from a tantalum metal surface. The peak absorbance of Mn and Mg is not appreciably affected by the material of the atomization surface. Interaction of Mn and Mg with the graphite surface and formation of their refractory carbides was found to be negligible. Uranium forms a refractory carbide when heated from a graphite surface.

Isotopic analysis of individual refractory metal nuggets using atom probe tomography

NASA Astrophysics Data System (ADS)

Daly, L.; Bland, P.; Schaefer, B. F.; Saxey, D. W.; Reddy, S.; Fougerouse, D.; William, R. D. A.; Forman, L. V.; Trimby, P.; La Fontaine, A.; Yang, L.; Cairney, J.; Ringer, S.

2016-12-01

Sub-micrometre metallic alloys of the highly siderophile elements, known as refractory metal nuggets (RMNs), can be found in primitive carbonaceous chondrites. There has been some suggestion that these grains may have a pre-solar origin, however their <1 µm size has meant that isotopic analysis of individual grains has not previously been possible. Atom probe microscopy has sufficient spatial resolution to quantify the isotopic compositions, across the entire mass range, of small sample volumes (<0.02 µm3) with high sensitivity and precision. We present analyses of four individual RMNs from the same refractory inclusion within the ALH 77307 meteorite. The results indicate that these RMNs have significant isotopic deviations from solar relative isotope abundances and therefore preserve a pre-solar isotopic signature. All RMNs exhibit large p-process enrichments in 98Ru and depletions in s-process 186Os. Two RMNs have a similar isotopic signature, suggesting formation in the same stellar environment. This similarity between two RMNs indicates that there may be a significant contribution of material to our solar system from a single source. The other two RMNs are isotopically dissimilar. Finally, three of the RMNs plot on a 187Re -187Os isochron from which we can derive a galactic age of 12.5 Ga ±1.8. To the best of our knowledge this is the first direct determination of the age of the Milky Way through physical analysis of non-solar material.

Targeting MTA1/HIF-1a signaling by pterostilbene in combination with histone deacetylase inhibitor attenuates prostate cancer progression

USDA-ARS?s Scientific Manuscript database

The metastasis-associated protein 1(MTA1)/ histone deacetylase (HDAC) unit is a cancer progression-related epigenetic regulator, which is overexpressed in hormone-refractory and metastatic prostate cancer. In our previous studies, we found a significantly increased MTA1 expression in a prostate-spec...

SUMMARY OF THE SEVENTH MEETING OF THE REFRACTORY COMPOSITES WORKING GROUP

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gibeaut, W.A.; Ogden, H.R.

1963-05-30

Information on refractory composites for use above 2500 deg F is summarized. Reports are concerned with protective coatings, insulating ceramics, materials for rocket thrust chambers, dispersion strengthening of metals, joining of refractory materials, and testing techniques. The problem of accelerated failure of silicide coatings under conditions of very low air pressure at high temperatures is studied. Although the maximum temperature capability of most silicide coatings is reduced about 50 theta deg at low air pressures, several coatings can protect molybdenum for 1/2 hr at 2800 to 3000 deg F under these conditions. The tin-aluminum coating also is susceptible to earlymore » failure at reduced pressure. An evaluation of the mechanical properties of 6-mil foils of D- 36, B-68, and TZM coated with commercial coatings demonstrated that some coatings seriously degrade substrate mechanical properties. Research on thermal- protection systems for re-entry vehicles whose surface temperatures reach from 3300 to 5500 deg F has resulted in agreement upon oxide coatings and thick metal- reinforced oxide composites. Simple plasmaarc-sprayed oxide coatings have demonstrated adequate oxidation resistance, but their structural stability in cyclic thermal exposure is inferior to metal-reinforced oxide. Thin unreinforced oxide coatings tend to spall in tests involving cyclic heating. A metal- reinforced oxide composite (reinforcement welded to substrate) has survived cyclic tests such as five 3-minute exposures at 4500 deg F without failing. A new carbon material called glassy carbon has demonstrnted better oxidation resistance than pyrolytic graphite at very high temperatures. The erosion resistance of pyrolytic graphite coatings on regular graphite in rocket firing tests using solid propellants is encouraging. There is considerable interest in fabricating small radiation-cooled rocket thrust chambers by plasma arc spraying. The design concept of internal reinforcement of sprayed-metal rocket chambers with wrought ductile wife appears impractical because of poor bonding and porosity around the wire. (auth)« less

[The study of gene mutations in unknown refractory viral infection and primary hemophagocytic lymphohistiocytosis].

PubMed

Tong, Chun-Rong; Liu, Hong-Xing; Xie, Jian-Jun; Wang, Fang; Cai, Peng; Wang, Hui; Zhu, Juan; Teng, Wen; Zhang, Xian; Yang, Jun-Fang; Zhang, Ya-Li; Fei, Xin-Hong; Zhao, Jie; Yin, Yu-Ming; Wu, Tong; Wang, Jing-Bo; Sun, Yuan; Liu, Rong; Shi, Xiao-Dong; Lu, Dao-Pei

2011-04-01

To study the type and corresponding clinical characteristics of primary hemophagocytic lymphohistiocytosis (HLH) associated immune gene mutations in the refractory virus infection or HLH of unknown causes. From December 2009 to July 2010, the patients with refractory virus infection or HLH of unknown causes were screened for the primary HLH associated immune genes mutations by DNA sequence analysis, including PRF1, UNC13D, STX11, STXBP2, SH2D1A and XIAP. The clinical characteristics and outcomes were followed up. Totally 25 patients with refractory virus infection or HLH of unknown causes were investigated for the 6 genes and 13 cases were found carrying gene mutations, composing of 6 of PRF1 mutation, 3 of UNC13D, and each one of STX11, XIAP, SH2D1A and STXBP2, respectively. Among the 13 cases with gene mutations, 5 suffered from Epstein-Barr virus associated HLH (EBV-HLH), 1 human herpes virus 7 associated HLH (HHV7-HLH), 1 HLH without causes, 4 chronic activated EB virus infection (CAEBV) with 1 progressing to Hodgkin's lymphoma carrying abnormal chromosome of t(15;17) (q22;q25) and hyperdiploid, 2 EBV associated lymphoma. Among the other 12 patients without gene mutation, 4 suffered from EBV-HLH with 1 progressing to peripheral T lymphoma, 8 suffered from CAEBV. Primary HLH associated immune gene mutations are critical causes of refractory virus infection of unknown causes, most patients manifest as HLH, some cases appear in CAEBV and EBV associated lymphoma. DNA sequence analysis is helpful to early diagnosis and correct decision-making for treatment.

Lenvatinib in Advanced Radioiodine-Refractory Thyroid Cancer - A Retrospective Analysis of the Swiss Lenvatinib Named Patient Program.

PubMed

Balmelli, Catharina; Railic, Nikola; Siano, Marco; Feuerlein, Kristin; Cathomas, Richard; Cristina, Valerie; Güthner, Christiane; Zimmermann, Stefan; Weidner, Sabine; Pless, Miklos; Stenner, Frank; Rothschild, Sacha I

2018-01-01

Purpose: Differentiated thyroid cancer (DTC) accounts for approximately 95% of thyroid carcinomas. In the metastatic RAI-refractory disease, chemotherapy has very limited efficacy and is associated with substantial toxicity. With increasing knowledge of the molecular pathogenesis of DTC, novel targeted therapies have been developed. Lenvatinib is a tyrosine kinase inhibitor (TKI) with promising clinical activity based on the randomized phase III SELECT trial. In Switzerland, a Named Patient Program (NPP) was installed to bridge the time gap to Swissmedic approval. Here, we report the results from the Swiss Lenvatinib NPP including patients with metastatic RAI-refractory DTC. Methods: Main inclusion criteria for the Swiss NPP were RAI-refractory DTC, documented disease progression, Eastern Cooperative Oncology Group (ECOG) performance status 0-3. The number of previous therapies was not limited. The Swiss Lenvatinib NPP was initiated in June 2014 and was closed in October 2015 with the approval of the drug. Results: Between June 2014 and October 2015, 13 patients with a median age of 72 years have been enrolled. Most patients (69%) had at least one prior systemic therapy, mainly sorafenib. 31% of patients showed a PR and 31% SD. Median progression free survival was 7.2 months and the median overall survival was 22.7 months. Dose reduction due to adverse events was necessary in 7 patients (53%). At the time of analysis 6 patients (47%) were still on treatment with a median time on treatment of 9.98 months. Conclusions: Our results show that lenvatinib has reasonable clinical activity in unselected patients with RAI-refractory thyroid cancer with nearly two-third of patients showing clinical benefit. The toxicity profile of lenvatinib is manageable.

Lenvatinib in Advanced Radioiodine-Refractory Thyroid Cancer - A Retrospective Analysis of the Swiss Lenvatinib Named Patient Program

PubMed Central

Balmelli, Catharina; Railic, Nikola; Siano, Marco; Feuerlein, Kristin; Cathomas, Richard; Cristina, Valerie; Güthner, Christiane; Zimmermann, Stefan; Weidner, Sabine; Pless, Miklos; Stenner, Frank; Rothschild, Sacha I.

2018-01-01

Purpose:Differentiated thyroid cancer (DTC) accounts for approximately 95% of thyroid carcinomas. In the metastatic RAI-refractory disease, chemotherapy has very limited efficacy and is associated with substantial toxicity. With increasing knowledge of the molecular pathogenesis of DTC, novel targeted therapies have been developed. Lenvatinib is a tyrosine kinase inhibitor (TKI) with promising clinical activity based on the randomized phase III SELECT trial. In Switzerland, a Named Patient Program (NPP) was installed to bridge the time gap to Swissmedic approval. Here, we report the results from the Swiss Lenvatinib NPP including patients with metastatic RAI-refractory DTC. Methods:Main inclusion criteria for the Swiss NPP were RAI-refractory DTC, documented disease progression, Eastern Cooperative Oncology Group (ECOG) performance status 0-3. The number of previous therapies was not limited. The Swiss Lenvatinib NPP was initiated in June 2014 and was closed in October 2015 with the approval of the drug. Results:Between June 2014 and October 2015, 13 patients with a median age of 72 years have been enrolled. Most patients (69%) had at least one prior systemic therapy, mainly sorafenib. 31% of patients showed a PR and 31% SD. Median progression free survival was 7.2 months and the median overall survival was 22.7 months. Dose reduction due to adverse events was necessary in 7 patients (53%). At the time of analysis 6 patients (47%) were still on treatment with a median time on treatment of 9.98 months. Conclusions:Our results show that lenvatinib has reasonable clinical activity in unselected patients with RAI-refractory thyroid cancer with nearly two-third of patients showing clinical benefit. The toxicity profile of lenvatinib is manageable. PMID:29344270

A PHASE II TRIAL OF THALIDOMIDE IN PATIENTS WITH REFRACTORY ENDOMETRIAL CANCER AND CORRELATION WITH ANGIOGENESIS BIOMARKERS: A GYNECOLOGIC ONCOLOGY GROUP STUDY

PubMed Central

McMeekin, D. Scott; Sill, Michael W.; Benbrook, Doris; Darcy, Kathleen M.; Stearns-Kurosawa, Deborah J.; Eaton, Lynne; Yamada, S. Diane

2007-01-01

Objectives A phase II trial was conducted to evaluate the anti-tumor activity and adverse effects of thalidomide in persistent or recurrent endometrial cancer refractory to cytotoxic chemotherapy, and to correlate angiogenesis biomarker expression with clinical outcome. Methods Consenting patients were treated until progression or intolerable toxicity with an oral starting dose of 200 mg thalidomide/day that was to increase by 200 mg every 2 weeks to a target dose of 1000 mg/day. Vascular endothelial growth factor (VEGF), basic fibroblastic growth factor (bFGF), and soluble endothelial protein C receptor (sEPCR) were analyzed by ELISA in pre and post-treatment specimens. Results Twenty-four of 27 patients enrolled in the study were eligible, of whom 2 reached the target dose, 8 progressed before achieving the target dose and 14 refused or had toxicity that prohibited escalation. Two patients (8.3%) remained progression-free ≥ 6 months. There were 3 (12.5%) with partial responses, 2 (8.3%) with stable disease, 15 (62.5%) with increasing disease, and 4 (16.7%) who were inevaluable for response. Median progression-free survival and overall survival were 1.7 months and 6.3 months, respectively. No grade 4 toxicities were observed. Common grade 3 toxicities included hematologic (n=3), cardiovascular (n=3), constitutional (n=3), and neurologic (n=4). Thalidomide did not decrease VEGF or bFGF levels but reduced sEPCR levels in serum. Elevated plasma vascular endothelial growth factor levels were associated with increased risk of progression and death. Conclusions Thalidomide demonstrated limited ability to delay progression (as measured by PFS at 6 months), produce objective responses or reduce angiogenic marker levels in chemotherapy refractory endometrial cancer. VEGF level appears to be prognostically significant in such patients, independent of thalidomide treatment. PMID:17306350

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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 basemore » 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 a critical thickness (0.0005 in.). A diffusion barrier that exceeded this thickness would likely fail. The joint fabrication method must therefore mechanically bond the two materials causing little or no interdiffusion upon formation. Co-extrusion fits this description since it forms a mechanical joint between two materials by using heat and pressure. The two materials to be extruded are first assembled and sealed within a co-extrusion billet which is subsequently heated and then extruded through a die. For a production application, once the joint is formed, it is dejacketed to remove the outer canister. The remaining piece consists of two materials bonded together with a thin diffusion barrier. Therefore, the long-term stability of the joint is determined primarily by the kinetics of interdiffusion reaction between the two materials. An experimental design for co-extrusion of refractory metals and nickel-based superalloys was developed to evaluate this joining process and determine the long-term stability of the joints.« less

Non-Contact Tabletop Mechanical Testing of Ultra-High Temperature Ceramics

DTIC Science & Technology

2012-05-01

class of refractory materials including transition metal borides , carbides and nitrides e.g. ZrB2l HfB2) ZrC, HfC, TaC, HfN and ZrN. They recently...ike oxidizing atmospheres, at very high temperatures Refractory borides like ZrB2 and HfB2 have extremely high melting temperatures (over 3000°C...But borides are very poor in oxidation resistance, due to the nature of thär oxides Non-protective ZrCfe or Hf02 and volatile liquid B203. Addition

Microstructure and Elevated Temperature Properties of a Refractory TaNbHfZrTi Alloy

DTIC Science & Technology

2012-01-24

composition of the TaNbHfZrTi alloy produced by vacuum arc melting Composition Ta Nb Hf Zr Ti at.% 19.68 18.93 20.46 21.23 19.7 wt. % 30.04 14.84 30.82 16.34...metallic materials with higher melting points, such as refractory molybdenum (Mo) and niobium ( Nb ) alloys, are examined as alternatives by academic and...creep resistance are the key properties of these alloys, since considerable alloy softening generally occurs at tempera- tures above *0.5 0.6 Tm

Long-term efficacy of anti-CD20 antibodies in refractory lupus nephritis.

PubMed

Arce-Salinas, C Alejandro; Rodríguez-García, Felipe; Gómez-Vargas, J Iván

2012-05-01

Eight patients with refractory lupus nephritis received rituximab after failing standard sequential therapy and were followed for 104 weeks after the infusion. One patient died secondary to a complicated pregnancy but had stable renal function. Three patients received a re-infusion of rituximab approximately 12 months apart due to a renal flare; during the second year of follow-up, those patients progressed toward ESRD. The four remaining patients demonstrated improvements in SLEDAI score, CrCl, and proteinuria with maintenance of their standard immunosuppressive therapy and did not require a re-infusion of rituximab. Although rituximab as induction therapy for refractory lupus nephritis has been shown to have a good response, its efficacy in long-term assessments demonstrates disappointing results.

Interactions of Alumina-Based and Magnesia-Based Refractories with Iron Melts and Slags: A Review

NASA Astrophysics Data System (ADS)

Sarkar, R.; Sohn, H. Y.

2018-06-01

A novel flash ironmaking technology (FIT) based on the direct reduction of iron ore concentrate with a reductant gas (such as hydrogen, natural gas, coal gas, or a combination thereof) in a flash furnace is being developed at the University of Utah. This technology which is undergoing large-scale laboratory testing aims at overcoming the limitations of blast furnace ironmaking by bypassing the problematic pelletization/sintering and cokemaking steps.[1-5] Refractory selection is expected to play an important step in the development of FIT and its proposed scale-up. For nominating an appropriate refractory for the FIT, understanding the interactions of candidate refractories with iron/iron oxide and slags under H2/CO/CO2/H2O environments is necessary. This work is undertaken to review the existing literature on the interactions of important refractories with iron melts and relevant slags with an emphasis on two of the most commonly used refractories in ironmaking and steelmaking applications: the alumina-based refractories (used widely in blast furnace operations) and the magnesia-based refractories (used extensively in primary as well as secondary steelmaking). First, a comprehensive review on the interactions of alumina-based refractories with iron melts and slags has been done. Next the existing literature on the interactions of magnesia-based refractories with iron melts and relevant slags has been reviewed. Summaries have been included after each section and sub-section along with comments and critical insights from the authors. Finally, in the concluding remarks the differences in operating conditions between existing iron and steelmaking practices and the novel FIT have been highlighted. On the basis of these differences, it has been argued that the results and conclusions available from previous studies on refractory-metal-slag interactions are of little significance to flash ironmaking. Thus, there exists a need to carry out laboratory experiments for evaluating refractory performance in flash ironmaking under conditions relevant to the current process (FIT).

ION PUMP

DOEpatents

Milleron, N.

1961-01-01

An ion pump and pumping method are given for low vacuum pressures in which gases introduced into a pumping cavity are ionized and thereafter directed and accelerated into a quantity of liquid gettering metal where they are absorbed. In the preferred embodiment the metal is disposed as a liquid pool upon one electrode of a Phillips ion gauge type pump. Means are provided for continuously and remotely withdrawing and degassing the gettering metal. The liquid gettering metal may be heated if desired, although various combinations of gallium, indium, tin, bismuth, and lead, the preferred metals, have very low melting points. A background pressure of evaporated gettering metal may be provided by means of a resistance heated refractory metal wick protruding from the surface of the pcol of gettering metal.

Outcome of children with relapsed or refractory neuroblastoma: A meta-analysis of ITCC/SIOPEN European phase II clinical trials.

PubMed

Moreno, Lucas; Rubie, Herve; Varo, Amalia; Le Deley, Marie Cecile; Amoroso, Loredana; Chevance, Aurelie; Garaventa, Alberto; Gambart, Marion; Bautista, Francisco; Valteau-Couanet, Dominique; Geoerger, Birgit; Vassal, Gilles; Paoletti, Xavier; Pearson, Andrew D J

2017-01-01

Few randomized trials have been conducted in children with relapsed/refractory neuroblastoma and data about outcomes including progression-free survival (PFS) in these patients are scarce. A meta-analysis of three phase II studies of children with relapsed/refractory neuroblastoma conducted in Europe (temozolomide, topotecan-vincristine-doxorubicin and topotecan-temozolomide) was performed. Individual patient data with extended follow-up were collected from the trial databases after publication to describe trial outcomes (response rate, clinical benefit ratio, duration of treatment, PFS, and overall survival [OS]). Characteristics of subjects with relapsed/refractory neuroblastoma were compared. Data from 71 children and adolescents with relapsed/refractory neuroblastoma were collected. Response definitions were not homogeneous in the three trials. Patients were on study for a median of 3.5 months (interquartile range [IQR] 1.9-6.2). Of those, 35.2% achieved a complete or partial response, 26.3% experienced a response after more than two cycles, and 23.9% received more than six cycles. Median PFS from study entry for all, refractory, and relapsed patients was 6.4 ± 1.0, 12.5 ± 6.8, and 5.7 ± 1.0 months, respectively (P = 0.006). Median OS from study entry for all, refractory, and relapsed patients was 16.1 ± 4.3, 27.9 ± 20.2, and 11.0 ± 1.6 months, respectively (P = 0.03). Baseline data for response rate, clinical benefit ratio, duration of treatment, PFS, and OS were provided. Two subpopulations (relapsed/refractory) were clearly distinct and should be included in the interpretation of all trials. These results should help informing the design of forthcoming studies in relapsed/refractory neuroblastoma. © 2016 Wiley Periodicals, Inc.

Fabrication of smooth patterned structures of refractory metals, semiconductors, and oxides via template stripping.

PubMed

Park, Jong Hyuk; Nagpal, Prashant; McPeak, Kevin M; Lindquist, Nathan C; Oh, Sang-Hyun; Norris, David J

2013-10-09

The template-stripping method can yield smooth patterned films without surface contamination. However, the process is typically limited to coinage metals such as silver and gold because other materials cannot be readily stripped from silicon templates due to strong adhesion. Herein, we report a more general template-stripping method that is applicable to a larger variety of materials, including refractory metals, semiconductors, and oxides. To address the adhesion issue, we introduce a thin gold layer between the template and the deposited materials. After peeling off the combined film from the template, the gold layer can be selectively removed via wet etching to reveal a smooth patterned structure of the desired material. Further, we demonstrate template-stripped multilayer structures that have potential applications for photovoltaics and solar absorbers. An entire patterned device, which can include a transparent conductor, semiconductor absorber, and back contact, can be fabricated. Since our approach can also produce many copies of the patterned structure with high fidelity by reusing the template, a low-cost and high-throughput process in micro- and nanofabrication is provided that is useful for electronics, plasmonics, and nanophotonics.

Phase II study of DFP-10917, a deoxycytidine analog, given by 14-day continuous intravenous infusion for chemotherapy-refractory advanced colorectal cancer.

PubMed

Mehrvarz Sarshekeh, Amir; Xiong, Henry Q; Iizuka, Kenzo; Hochster, Howard S; Kopetz, Scott

2018-06-13

Background DFP-10917 is a cytotoxic deoxycytidine analogue that causes DNA fragmentation, G 2 /M-phase arrest, and apoptosis. This agent has been shown to have antitumor activity against colorectal cancer (CRC) in preclinical studies and to be tolerable in patients. The purpose of our phase II trial was to evaluate the safety, efficacy and pharmacogenomics of DFP-10917 as well as DNA damage studies in patients with advanced CRC refractory to cytotoxic chemotherapy. Methods In this single-arm, Simon two-stage, phase II trial, patients with chemotherapy-refractory advanced CRC received 2.0 mg/m 2 /day DFP-10917 via 14-day continuous infusion. Enrollment criteria included age ≥ 18 years, Eastern Cooperative Oncology Group status of 0 or 1, and adequate organ function. The primary endpoint was 3-month progression-free survival, defined as the proportion of patients who did not have progressive disease or death within 3 months of starting therapy. All patients who received any amount of DFP-10917 were included in the safety analysis. DNA damage study was assessed by comet assay. Results Of 28 patients initially enrolled, 26 received DFP-10917. Three patients (12%) were progression free at 3 months. The median progression-free survival was 1.3 months (95% confidence interval, 1.3-1.6 months). There were no complete or partial responses. Most patients (n = 20, 77%) had progressive disease, and only six (23%) had stable disease at any time. The trial was terminated according to the pre-planned stopping rule. The most frequent (≥5%) medication-related grade 3 or higher adverse events were neutropenia (n = 10, 38%), fatigue (n = 4, 15%), anemia (n = 3, 12%), and leukopenia (n = 3, 12%). DNA strand-breaks were detected after infusion (medians of % tail intensity were 2.89 and 12.64 on day 1 and day 15, respectively, p < 0.001, sign test). Conclusion Overall, single-agent DFP-10917 did not show meaningful antitumor activity in chemotherapy-refractory advanced CRC. The safety profile of DFP-10917 was tolerable and similar to that observed in earlier clinical studies.

Cold machining of high density tungsten and other materials

NASA Technical Reports Server (NTRS)

Ziegelmeier, P.

1969-01-01

Cold machining process, which uses a sub-zero refrigerated cutting fluid, is used for machining refractory or reactive metals and alloys. Special carbide tools for turning and drilling these alloys further improve the cutting performance.

Ensuring the Consistency of Silicide Coatings

NASA Technical Reports Server (NTRS)

Ramani, V.; Lampson, F. K.

1982-01-01

Diagram specifies optimum fusing time for given thicknesses of refractory metal-silicide coatings on columbium C-103 substrates. Adherence to indicated fusion times ensures consistent coatings and avoids underdiffusion and overdiffusion. Accuracy of diagram has been confirmed by tests.

Origin of spinel-rich chondrules and inclusions in carbonaceous and ordinary chondrites

NASA Technical Reports Server (NTRS)

Kornacki, A. S.; Fegley, B., Jr.

1984-01-01

The evaluation of three models of the origin of spinel-rich chondrules and inclusions presented here includes new calculations of the major-element refractory mineral condensation sequence from a gas of solar composition over a wide pressure interval. Condensation calculations show that spinel-rich chondrules did not crystallize from metastable liquid condensates, and that spinel-rich inclusions are not aggregates of refractory nebular condensates. It is proposed that spinel-rich objects are fractionated distillation residues of small aggregates of primitive dust that lost Ca, Si-rich partial melts by evaporation, ablation, or splashing during collisions. This model also explains why spinel-rich chondrules and inclusions (1) are usually smaller than melilite-rich chondrules and inclusions; (2) often have highly fractionated trace-element compositions; and (3) usually do not contain Pt-metal nuggets even when they are more enriched in the Pt-group metals than nugget-bearing melilite-rich objects.

Refractory metal alloys and composites for space power systems

NASA Technical Reports Server (NTRS)

Stephens, Joseph R.; Petrasek, Donald W.; Titran, Robert H.

1988-01-01

Space power requirements for future NASA and other U.S. missions will range from a few kilowatts to megawatts of electricity. Maximum efficiency is a key goal of any power system in order to minimize weight and size so that the space shuttle may be used a minimum number of times to put the power supply into orbit. Nuclear power has been identified as the primary source to meet these high levels of electrical demand. One way to achieve maximum efficiency is to operate the power supply, energy conversion system, and related components at relatively high temperatures. NASA Lewis Research Center has undertaken a research program on advanced technology of refractory metal alloys and composites that will provide baseline information for space power systems in the 1900's and the 21st century. Basic research on the tensile and creep properties of fibers, matrices, and composites is discussed.

Vacuum Plasma Spray (VPS) Forming of Solar Thermal Propulsion Components Using Refractory Metals

NASA Technical Reports Server (NTRS)

Zimmerman, Frank; Gerish, Harold; Davis, William; Hissam, D. Andy

1998-01-01

The Thermal Spray Laboratory at NASA's Marshall Space Flight Center has developed and demonstrated a fabrication technique using Vacuum Plasma Spray (VPS) to form structural components from a tungsten/rhenium alloy. The components were assembled into an absorption cavity for a fully-functioning, ground test unit of a solar thermal propulsion engine. The VPS process deposits refractory metal onto a graphite mandrel of the desired shape. The mandrel acts as a male mold, forming the required contour and dimensions of the inside surface of the deposit. Tungsten and tungsten/25% rhenium were used in the development and production of several absorber cavity components. These materials were selected for their high temperature (less than 2500 C) strength. Each absorber cavity comprises 3 coaxial shells with two, double-helical flow passages through which the propellant gas flows. This paper describes the processing techniques, design considerations, and process development associated with forming these engine components.

Refractory Metal Heat Pipe Life Test - Test Plan and Standard Operating Procedures

NASA Technical Reports Server (NTRS)

Martin, J. J.; Reid, R. S.

2010-01-01

Refractory metal heat pipes developed during this project shall be subjected to various operating conditions to evaluate life-limiting corrosion factors. To accomplish this objective, various parameters shall be investigated, including the effect of temperature and mass fluence on long-term corrosion rate. The test series will begin with a performance test of one module to evaluate its performance and to establish the temperature and power settings for the remaining modules. The performance test will be followed by round-the-clock testing of 16 heat pipes. All heat pipes shall be nondestructively inspected at 6-month intervals. At longer intervals, specific modules will be destructively evaluated. Both the nondestructive and destructive evaluations shall be coordinated with Los Alamos National Laboratory. During the processing, setup, and testing of the heat pipes, standard operating procedures shall be developed. Initial procedures are listed here and, as hardware is developed, will be updated, incorporating findings and lessons learned.

Trace elements in ocean ridge basalts

NASA Technical Reports Server (NTRS)

Kay, R. W.; Hubbard, N. J.

1978-01-01

A study is made of the trace elements found in ocean ridge basalts. General assumptions regarding melting behavior, trace element fractionation, and alteration effects are presented. Data on the trace elements are grouped according to refractory lithophile elements, refractory siderophile elements, and volatile metals. Variations in ocean ridge basalt chemistry are noted both for regional and temporal characteristics. Ocean ridge basalts are compared to other terrestrial basalts, such as those having La/Yb ratios greater than those of chondrites, and those having La/Yb ratios less than those of chondrites. It is found that (1) as compared to solar or chondrite ratios, ocean ridge basalts have low ratios of large, highly-charged elements to smaller less highly-charged elements, (2) ocean ridge basalts exhibit low ratios of volatile to nonvolatile elements, and (3) the transition metals Cr through Zn in ocean ridge basalts are not fractionated more than a factor of 2 or 3 from the chondritic abundance ratios.

A phase 2 trial of lenalidomide, bortezomib, and dexamethasone in patients with relapsed and relapsed/refractory myeloma

PubMed Central

Xie, Wanling; Jagannath, Sundar; Jakubowiak, Andrzej; Lonial, Sagar; Raje, Noopur S.; Alsina, Melissa; Ghobrial, Irene M.; Schlossman, Robert L.; Munshi, Nikhil C.; Mazumder, Amitabha; Vesole, David H.; Kaufman, Jonathan L.; Colson, Kathleen; McKenney, Mary; Lunde, Laura E.; Feather, John; Maglio, Michelle E.; Warren, Diane; Francis, Dixil; Hideshima, Teru; Knight, Robert; Esseltine, Dixie-Lee; Mitsiades, Constantine S.; Weller, Edie; Anderson, Kenneth C.

2014-01-01

In this prospective, multicenter, phase 2 study, 64 patients with relapsed or relapsed and refractory multiple myeloma (MM) received up to 8 21-day cycles of bortezomib 1.0 mg/m2 (days 1, 4, 8, and 11), lenalidomide 15 mg/day (days 1-14), and dexamethasone 40/20 mg/day (cycles 1-4) and 20/10 mg/day (cycles 5-8) (days of/after bortezomib dosing). Responding patients could receive maintenance therapy. Median age was 65 years; 66% were male, 58% had relapsed and 42% had relapsed and refractory MM, and 53%, 75%, and 6% had received prior bortezomib, thalidomide, and lenalidomide, respectively. Forty-eight of 64 patients (75%; 90% confidence interval, 65-84) were alive without progressive disease at 6 months (primary end point). The rate of partial response or better was 64%; median duration of response was 8.7 months. Median progression-free and overall survivals were 9.5 and 30 months, respectively (median follow-up: 44 months). Common treatment-related toxicities included sensory neuropathy (53%), fatigue (50%), and neutropenia (42%); common grade 3/4 treatment-related toxicities included neutropenia (30%), thrombocytopenia (22%), and lymphopenia (11%). Grade 3 motor neuropathy was reported in 2 patients. Lenalidomide-bortezomib-dexamethasone appears effective and tolerable in patients with relapsed or relapsed and refractory MM, demonstrating substantial activity among patients with diverse prior therapies and adverse prognostic characteristics. This trial is registered with www.clinicaltrials.gov as #NCT00378209. PMID:24429336

Orbiting dynamic compression laboratory

NASA Technical Reports Server (NTRS)

Ahrens, T. J.; Vreeland, T., Jr.; Kasiraj, P.; Frisch, B.

1984-01-01

In order to examine the feasibility of carrying out dynamic compression experiments on a space station, the possibility of using explosive gun launchers is studied. The question of whether powders of a refractory metal (molybdenum) and a metallic glass could be well considered by dynamic compression is examined. In both cases extremely good bonds are obtained between grains of metal and metallic glass at 180 and 80 kb, respectively. When the oxide surface is reduced and the dynamic consolidation is carried out in vacuum, in the case of molybdenum, tensile tests of the recovered samples demonstrated beneficial ultimate tensile strengths.

Historical time to disease progression and progression-free survival in patients with recurrent/refractory neuroblastoma treated in the modern era on Children's Oncology Group early-phase trials.

PubMed

London, Wendy B; Bagatell, Rochelle; Weigel, Brenda J; Fox, Elizabeth; Guo, Dongjing; Van Ryn, Collin; Naranjo, Arlene; Park, Julie R

2017-12-15

Early-phase trials in patients with recurrent neuroblastoma historically used an objective "response" of measureable disease (Response Evaluation Criteria In Solid Tumors [RECIST], without bone/bone marrow assessment) to select agents for further study. Historical cohorts may be small and potentially biased; to the authors' knowledge, disease recurrence studies from international registries are outdated. Using a large recent cohort of patients with recurrent/refractory neuroblastoma from Children's Oncology Group (COG) modern-era early-phase trials, the authors determined outcome and quantified parameters for designing future studies. The first early-phase COG trial enrollment (sequential) of 383 distinct patients with recurrent/refractory neuroblastoma on 23 phase 1, 3 phase 1/2, and 9 phase 2 trials (August 2002 to January 2014) was analyzed for progression-free survival (PFS), overall survival (OS), and time to disease progression (TTP). Planned frontline therapy for patients with high-risk neuroblastoma included hematopoietic stem cell transplantation (approximately two-thirds of patients underwent ≥1 hematopoietic stem cell transplantation); 13.2% of patients received dinutuximab. From the time of the patient's first early-phase trial enrollment (383 patients), the 1-year and 4-year PFS rates ( ± standard error) were 21% ± 2% and 6% ± 1%, respectively, whereas the 1-year and 4-year OS rates were 57% ± 3% and 20% ± 2%, respectively. The median TTP was 58 days (interquartile range, 31-183 days [350 patients]); the median follow-up was 25.3 months (33 patients were found to be without disease recurrence/progression). The median time from diagnosis to first disease recurrence/progression was 18.7 months (range, 1.4-64.8 months) (176 patients). MYCN amplification and 11q loss of heterozygosity were prognostic of worse PFS and OS (P = .003 and P<.0001, respectively, and P = .02 and P = .03, respectively) after early-phase trial enrollment. This recent COG cohort of patients with recurrent/refractory neuroblastoma is inclusive and representative. To the authors' knowledge, the current study is the first meta-analysis of PFS, TTP, and OS within the context of modern therapy. These results will inform the design of future phase 2 studies by providing a) historical context during the search for more effective agents; and, b) factors prognostic of PFS and OS after disease recurrence to stratify randomization. Cancer 2017;123:4914-23. © 2017 American Cancer Society. © 2017 American Cancer Society.

Positron emission tomography response at the time of autologous stem cell transplantation predicts outcome of patients with relapsed and/or refractory Hodgkin’s lymphoma responding to prior salvage therapy

PubMed Central

Devillier, Raynier; Coso, Diane; Castagna, Luca; Brenot Rossi, Isabelle; Anastasia, Antonella; Chiti, Arturo; Ivanov, Vadim; Schiano, Jean Marc; Santoro, Armando; Chabannon, Christian; Balzarotti, Monica; Blaise, Didier; Bouabdallah, Reda

2012-01-01

Background High-dose chemotherapy followed by autologous stem cell transplantation is the standard treatment for relapsed and/or refractory Hodgkin’s lymphoma although half of patients relapse after transplantation. Predictive factors, such as relapse within 12 months, Ann-Arbor stage at relapse, and relapse in previously irradiated fields are classically used to identify patients with poor outcome. Recently, 18-fluorodeoxyglucose positron emission tomography has emerged as a new method for providing information to predict outcome. The aim of this study was to confirm the predictive value of positron emission tomography status after salvage therapy and to compare single versus tandem autologous stem cell transplantation in patients with relapsed and/or refractory Hodgkin’s lymphoma. Design and Methods We report a series of 111 consecutive patients with treatment-sensitive relapsed and/or treatment-refractory Hodgkin’s lymphoma who achieved complete (positron emission tomography-negative group) or partial remission (positron emission tomography-positive group) at positron emission tomography evaluation after salvage chemotherapy and who underwent single or tandem autologous stem cell transplantation. Results Five-year overall and progression-free survival rates were 81% and 64%, respectively. There were significant differences in 5-year progression-free survival (79% versus 23%; P<0.001) and 5-year overall survival (90% versus 55%, P=0.001) between the positron emission tomography-negative and -positive groups, respectively. A complete response, as determined by positron emission tomography evaluation, after salvage therapy predicted significantly better 5-year overall survival rates in both intermediate (91% versus 50%; P=0.029) and unfavorable (89% versus 58%; P=0.026) risk subgroup analyses. In the positron emission tomography-positive subgroup, tandem transplantation improved 5-year progression-free survival from 0% (in the single transplantation group) to 43% (P=0.034). Multivariate analysis showed that positron emission tomography status (hazard ratio: 5.26 [2.57–10.73]) and tandem transplantation (hazard ratio: 0.39 [0.19–0.78]) but not risk factors at relapse (hazard ratio: 1.77 [0.80–3.92]) significantly influenced progression-free survival, while only tomography status significantly influenced overall survival (hazard ratio: 4.03 [1.38–11.75]). Conclusions In patients with relapsed/refractory Hodgkin’s lymphoma responding to prior salvage therapy, positron emission tomography response at time of autologous stem cell transplantation favorably influences outcome and enables identification of patients requiring single or tandem transplantation. PMID:22271893

Metallic Full-Length Ureteral Stents: Does Urinary Tract Infection Cause Obstruction?

PubMed Central

Brown, James A.; Powell, Christopher L.; Carlson, Kristopher R.

2010-01-01

Metallic ureteral stents promise to offer superior upper urinary tract drainage with extended exchange intervals and freedom from extrinsic compression in patients with advanced malignancy or other significant obstructing retroperitoneal or pelvic processes. Existing literature indicates a variable experience with these relatively new devices, with some investigators reporting excellent results and long problem-free intervals, and others reporting less enthusiastic outcomes. We report a retrospective review of a series of five sequential patients undergoing placement of Resonance® (Cook Medical, Bloomington, IN) metallic ureteral stents for extrinsic ureteral compression refractory to placement of traditional (polymer) ureteral stents. Of five patients reviewed, three (60%) required additional operative intervention for stent migration or malposition. Four patients (80%) died of their primary malignancy <12 months after metallic stent placement. Four (80%) of five patients had obstruction of their stents demonstrated with nuclear renography and/or other imaging, and three (60%) required removal and alternative means of urinary tract drainage within 4 months of placement due to obstruction, intractable pain, or migration. Four patients (80%) had urinary tract infections (UTIs) within 4 months of stent placement. No obstruction was seen due to extrinsic ureteral compression after stent placement. Metallic ureteral stents may have utility for patients with pathological processes causing extrinsic ureteral compression refractory to the use of traditional polymer ureteral stents. However, metallic ureteral stents are not immune to obstruction, migration, and associated discomfort. Stent obstruction appears to be increased in patients with postoperative UTI. PMID:20730376

Metallic full-length ureteral stents: does urinary tract infection cause obstruction?

PubMed

Brown, James A; Powell, Christopher L; Carlson, Kristopher R

2010-08-17

Metallic ureteral stents promise to offer superior upper urinary tract drainage with extended exchange intervals and freedom from extrinsic compression in patients with advanced malignancy or other significant obstructing retroperitoneal or pelvic processes. Existing literature indicates a variable experience with these relatively new devices, with some investigators reporting excellent results and long problem-free intervals, and others reporting less enthusiastic outcomes. We report a retrospective review of a series of five sequential patients undergoing placement of Resonance (Cook Medical, Bloomington, IN) metallic ureteral stents for extrinsic ureteral compression refractory to placement of traditional (polymer) ureteral stents. Of five patients reviewed, three (60%) required additional operative intervention for stent migration or malposition. Four patients (80%) died of their primary malignancy <12 months after metallic stent placement. Four (80%) of five patients had obstruction of their stents demonstrated with nuclear renography and/or other imaging, and three (60%) required removal and alternative means of urinary tract drainage within 4 months of placement due to obstruction, intractable pain, or migration. Four patients (80%) had urinary tract infections (UTIs) within 4 months of stent placement. No obstruction was seen due to extrinsic ureteral compression after stent placement. Metallic ureteral stents may have utility for patients with pathological processes causing extrinsic ureteral compression refractory to the use of traditional polymer ureteral stents. However, metallic ureteral stents are not immune to obstruction, migration, and associated discomfort. Stent obstruction appears to be increased in patients with postoperative UTI.

The ketogenic diet in two paediatric patients with refractory myoclonic status epilepticus.

PubMed

Caraballo, Roberto Horacio; Valenzuela, Gabriela Reyes; Armeno, Marisa; Fortini, Sebastian; Mestre, Graciela; Cresta, Araceli

2015-12-01

We describe two patients with refractory myoclonic status epilepticus treated with the ketogenic diet. Between May 1, 2014 and January 1, 2015, two patients who met the diagnostic criteria for refractory myoclonic status epilepticus, seen at our department, were placed on the ketogenic diet and followed for a minimum of six months. One patient with myoclonic epilepsy of unknown aetiology had a 75-90% seizure reduction, and the other with progressive encephalopathy associated with myoclonic epilepsy had a 50% seizure reduction. Both patients retained good tolerability for the diet. At the last control, one patient had isolated myoclonias and EEG showed occasional generalized spike-and-polyspike waves; the patient is now successfully attending kindergarten. The quality of life of the second patient improved significantly. In both cases, the number of antiepileptic drugs was reduced. The ketogenic diet is an effective and well-tolerated treatment option for patients with refractory myoclonic status epilepticus and should be considered earlier in the course of treatment.

Tensile Behavior of Electron Beam-Welded and Post-Weld Vacuum-Annealed Nb-10% Hf-1% Ti Refractory Alloy Weldments

NASA Astrophysics Data System (ADS)

Anil Kumar, V.; Gupta, R. K.; Venkateswaran, T.; Ram Kumar, P.

2018-02-01

Nb-10% Hf-1% Ti refractory alloy is a high performance material extensively used for high temperature applications. Electron beam welding is one of the most widely used techniques to join refractory and reactive alloys. Bigger sizes of nozzles for rocket propulsion applications can be either made through deep drawing and flow turning route or by roll bending and welding route both using sheets/plates as input material for fabrication. The latter is a more economical option for mass production of the hardware using such exotic and expensive alloys. In view of this, both as-welded (AW) coupon and weld plus post-weld vacuum-annealed (AW + VA) coupon have been prepared to study their mechanical behavior. It has been observed that tensile strength and ductility have not been reduced in both these conditions vis-à-vis the base metal, confirming weld efficiency of the alloy to be 100%. Microhardness is found to be 150-160 VHN in the base metal and 200-225 VHN in the weld fusion zone in AW condition, which became uniform (145-155 VHN) throughout the weldment in AW + VA condition. Microstructure of the weldment in AW condition is found to be consisting of grains solidified by epitaxial mode from base metal toward the weld centre. In AW + VA condition, improvement in tensile elongation is observed, which is found to be due to the presence of homogenized grains/more uniform microstructure near the heat-affected zone as compared to the steep gradient in grain size in different zones in the weld in AW condition.

Little Chondrules and Giant Impacts

NASA Astrophysics Data System (ADS)

Taylor, G. J.

2005-10-01

Alexander (Sasha) Krot (University of Hawaii), Yuri Amelin (University of Toronto), Pat Cassen (SETI Institute), and Anders Meibom (Museum National d'Histoire Naturelle, Paris) studied and then extracted frozen droplets of molten silicate (chondrules) from unusual meteorites rich in metallic iron-nickel. Called CB (Bencubbin-like) chondrites, these rare but fascinating meteorites contain chondrules with different properties than those in other types of chondrites. Most notably, the chondrules contain very small concentrations of volatile elements and variable concentrations of refractory elements. (Volatile elements condense from a gas at a relatively low temperature, or are boiled out of solids or liquids at relatively low temperature. Refractory elements are the opposite.) Some of the metal grains in CB chondrites are chemically zoned, indicating that they formed by condensation in a vapor cloud. The most intriguing feature of chondrules in CB chondrites is their relatively young age. Lead-lead isotopic dating of chondrules separated from two CB chondrites show that they formed 5 million years after formation of the first solids in the solar system (calcium-aluminum-rich inclusions), which is about at least two million years after formation of other chondrules, and after energetic events in the solar nebula stopped. Krot and his colleagues suggest that the CB chondrules formed as the result of an impact between Moon- to Mars-sized protoplanets. Such impacts were so energetic that huge amounts of material were vaporized and then condensed as chondrules or chemically zoned metal grains. This event enriched refractory elements and depleted volatile elements. Such large impacts appear to play important roles in planet formation, including the formation of the Moon.

Lifetime cost of everolimus vs axitinib in patients with advanced renal cell carcinoma who failed prior sunitinib therapy in the US.

PubMed

Perrin, Allison; Sherman, Steven; Pal, Sumanta; Chua, Andrew; Gorritz, Magdaliz; Liu, Zhimei; Wang, Xufang; Culver, Kenneth; Casciano, Roman; Garrison, Louis P

2015-03-01

Everolimus and axitinib are approved in the US to treat patients with advanced renal cell carcinoma (RCC) after failure on sunitinib or sorafenib, and one prior systemic therapy (e.g., sunitinib), respectively. Two indirect comparisons performed to evaluate progression-free survival in patients treated with everolimus vs axitinib suggested similar efficacy between the two treatments. Therefore, this analysis compares the lifetime costs of these two therapies among sunitinib-refractory advanced RCC patients from a US payer perspective. A Markov model was developed to simulate a cohort of sunitinib-refractory advanced RCC patients and estimate the cost of treating patients with everolimus vs axitinib. The following health states were included: stable disease without adverse events (AEs), stable disease with AEs, disease progression (PD), and death. The model included the following resources: active treatments, post-progression treatments, adverse events, physician and nurse visits, scans and tests, and palliative care. Resource utilization inputs were derived from a US claims database analysis. Additionally, a 3% annual discount rate was applied to costs, and the robustness of the model results was tested by conducting sensitivity analyses, including those on dosing scheme and post-progression treatment costs. Base case results demonstrated that patients treated with everolimus cost an average of $12,985 (11%) less over their lifetimes than patients treated with axitinib. The primary difference in costs was related to active treatment, which was largely driven by axitinib's higher dose intensity. RESULTS remained consistent across sensitivity analyses for AE and PD treatment costs, as well as dose intensity and discount rates. The results suggest that everolimus likely leads to lower lifetime costs than axitinib for sunitinib-refractory advanced RCC patients in the US.

Bevacizumab and Irinotecan in Treating Young Patients With Recurrent, Progressive, or Refractory Glioma, Medulloblastoma, Ependymoma, or Low Grade Glioma

ClinicalTrials.gov

2017-10-23

Childhood Cerebral Anaplastic Astrocytoma; Childhood Oligodendroglioma; Childhood Spinal Cord Neoplasm; Recurrent Childhood Brain Stem Glioma; Recurrent Childhood Ependymoma; Recurrent Childhood Medulloblastoma

Palliative management of refractory dyspnea in COPD

PubMed Central

Uronis, Hope E; Currow, David C; Abernethy, Amy P

2006-01-01

COPD is a progressive illness with worldwide impact. Patients invariably reach a point at which they require palliative interventions. Dyspnea is the most distressing symptom experienced by these patients; when not relieved by traditional COPD management strategies it is termed “refractory dyspnea” and palliative approaches are required. The focus of care shifts from prolonging survival to reducing symptoms, increasing function, and improving quality of life. Numerous pharmacological and non-pharmacological interventions can achieve these goals, though evidence supporting their use is variable. This review provides a summary of the options for the management of refractory dyspnea in COPD, outlining currently available evidence and highlighting areas for further investigation. Topics include oxygen, opioids, psychotropic drugs, inhaled furosemide, Heliox, rehabilitation, nutrition, psychosocial support, breathing techniques, and breathlessness clinics. PMID:18046866

Formation of the Structure of a Eutectic Alloy of the Nb - Si System During Directed Crystallization with Liquid-Metal Coolant

NASA Astrophysics Data System (ADS)

Bondarenko, Yu. A.; Echin, A. B.; Kolodyazhnyi, M. Yu.; Surova, V. A.

2017-11-01

Peculiarities of the structure of a refractory eutectic alloy of the Nb - Si system, formed by the method of directed crystallization with liquid-metal coolant, have been studied. Characteristic zones of microstructure of the ingot obtained upon directed crystallization are considered, the alloy composition is analyzed, and volume fractions of phases in the Nb - Si composite are determined.

Refining a complex nickel alloy to remove a sulfur impurity during vacuum induction melting: Part II

NASA Astrophysics Data System (ADS)

Sidorov, V. V.; Min, P. G.

2014-12-01

The results of studying the refining of complexly alloyed nickel melts from sulfur during melting in a vacuum induction furnace or with the use of an oxide calcium crucible, metallic calcium added to a melt, or rare-earth metals additions (which form thermodynamically stable refractory compounds with sulfur and, thus, eliminate the harmful effect of sulfur in the alloys) are reported.

Coordinated Isotopic and TEM Studies of Presolar Graphites from Murchison

NASA Astrophysics Data System (ADS)

Croat, T. K.; Stadermann, F. J.; Zinner, E.; Bernatowicz, T. J.

2004-03-01

TEM and NanoSIMS investigations of the same presolar Murchison KFC graphites revealed high Zr, Mo, and Ru content in refractory carbides within the graphites. Along with isotopically light carbon, these suggest a low-metallicity AGB source.

Physical and Chemical Properties of Anthropogenic Aerosols: An Overview

EPA Science Inventory

Aerosol chemical composition is complex. Combustion aerosols can comprise tens of thousands of organic compounds, refractory brown and black carbon, heavy metals, cations, anions, salts, and other inorganic phases. Aerosol organic matter normally contains semivolatile material th...

Metal Matrix Composite LOX Turbopump Housing Via Novel Tool-Less Net-Shape Pressure Infiltration Casting Technology

NASA Technical Reports Server (NTRS)

Shah, Sandeep; Lee, Jonathan; Bhat, Biliyar; Wells, Doug; Gregg, Wayne; Marsh, Matthew; Genge, Gary; Forbes, John; Salvi, Alex; Cornie, James A.;

Metal Matrix Composite LOX Turbopump Housing Via Novel Tool-Less Net-Shape Pressure Infiltration Casting Technology

NASA Technical Reports Server (NTRS)

Shah, Sandeep; Lee, Jonathan; Bhat, Biliyar; Wells, Doug; Gregg, Wayne; Marsh, Matthew; Genge, Gary; Forbes, John; Salvi, Alex; Cornie, James A.;

Metal Matrix Composite LOX Turbopump Housing Via Novel Tool-less Net-Shape Pressure Infiltration Casting Technology

NASA Technical Reports Server (NTRS)

Shah, Sandeep; Lee, Jonathan; Bhat, Biliyar; Wells, Doug; Gregg, Wayne; Marsh, Matthew; Genge, Gary; Forbes, John; Salvi, Alex; Cornie, James A.;

A Comparison of Fission Power System Options for Lunar and Mars Surface Applications

NASA Technical Reports Server (NTRS)

Mason, Lee S.

2006-01-01

This paper presents a comparison of reactor and power conversion design options for 50 kWe class lunar and Mars surface power applications with scaling from 25 to 200 kWe. Design concepts and integration approaches are provided for three reactor-converter combinations: gas-cooled Brayton, liquid-metal Stirling, and liquid-metal thermoelectric. The study examines the mass and performance of low temperature, stainless steel based reactors and higher temperature refractory reactors. The preferred system implementation approach uses crew-assisted assembly and in-situ radiation shielding via installation of the reactor in an excavated hole. As an alternative, self-deployable system concepts that use earth-delivered, on-board radiation shielding are evaluated. The analyses indicate that among the 50 kWe stainless steel reactor options, the liquid-metal Stirling system provides the lowest mass at about 5300 kg followed by the gas-cooled Brayton at 5700 kg and the liquid-metal thermoelectric at 8400 kg. The use of a higher temperature, refractory reactor favors the gas-cooled Brayton option with a system mass of about 4200 kg as compared to the Stirling and thermoelectric options at 4700 and 5600 kg, respectively. The self-deployed concepts with on-board shielding result in a factor of two system mass increase as compared to the in-situ shielded concepts.

Diffusion of Siderophile Elements in Fe Metal: Application to Zoned Metal Grains in Chondrites

NASA Technical Reports Server (NTRS)

Righter, K.; Campbell, A. J.; Humajun, M.

2003-01-01

The distribution of highly siderophile elements (HSE) in planetary materials is controlled mainly by metal. Diffusion processes can control the distribution or re-distribution of these elements within metals, yet there is little systematic or appropriate diffusion data that can be used to interpret HSE concentrations in such metals. Because our understanding of isotope chronometry, redox processes, kamacite/taenite-based cooling rates, and metal grain zoning would be enhanced with diffusion data, we have measured diffusion coefficients for Ni, Co, Ga, Ge, Ru, Pd, Ir and Au in Fe metal from 1200 to 1400 C and 1 bar and 10 kbar. These new data on refractory and volatile siderophile elements are used to evaluate the role of diffusional processes in controlling zoning patterns in metal-rich chondrites.

Complete intracranial response to talimogene laherparepvec (T-Vec), pembrolizumab and whole brain radiotherapy in a patient with melanoma brain metastases refractory to dual checkpoint-inhibition.

PubMed

Blake, Zoë; Marks, Douglas K; Gartrell, Robyn D; Hart, Thomas; Horton, Patti; Cheng, Simon K; Taback, Bret; Horst, Basil A; Saenger, Yvonne M

2018-04-06

Immunotherapy, in particular checkpoint blockade, has changed the clinical landscape of metastatic melanoma. Nonetheless, the majority of patients will either be primary refractory or progress over follow up. Management of patients progressing on first-line immunotherapy remains challenging. Expanded treatment options with combination immunotherapy has demonstrated efficacy in patients previously unresponsive to single agent or alternative combination therapy. We describe the case of a patient with diffusely metastatic melanoma, including brain metastases, who, despite being treated with stereotactic radiosurgery and dual CTLA-4/PD-1 blockade (ipilimumab/nivolumab), developed systemic disease progression and innumerable brain metastases. This patient achieved a complete CNS response and partial systemic response with standard whole brain radiation therapy (WBRT) combined with Talimogene laherparepvec (T-Vec) and pembrolizumab. Patients who do not respond to one immunotherapy combination may respond during treatment with an alternate combination, even in the presence of multiple brain metastases. Biomarkers are needed to assist clinicians in evidence based clinical decision making after progression on first line immunotherapy to determine whether response can be achieved with second line immunotherapy.

Liquid metal micro heat pipes for space radiator applications

NASA Technical Reports Server (NTRS)

Gerner, F. M.; Henderson, H. T.

1995-01-01

Micromachining is a chemical means of etching three-dimensional structures, typically in single-crystalline silicon. These techniques are leading toward what is coming to be referred to as MEMS (micro electro mechanical systems), where in addition to the ordinary two dimensional (planar) microelectronics, it is possible to build three-dimensional micromotors, electrically-actuated microvalves, hydraulic systems, and much more on the same microchip. These techniques become possible because of differential etching rates of various crystallographic planes and materials used for semiconductor microfabrication. The University of Cincinnati group in collaboration with NASA Lewis formed micro heat pipes in silicon by the above techniques. Work is ongoing at a modest level, but several essential bonding and packaging techniques have been recently developed. Currently, we have constructed and filled water/silicon micro heat pipes. Preliminary thermal tests of arrays of 125 micro heat pipes etched in a 1 inch x 1 inch x 250 micron silicon wafer have been completed. These pipes are instrumented with extremely small P-N junctions to measure their effective conductivity and their maximum operating power. A relatively simple one-dimensional model has been developed in order to predict micro heat pipes' operating characteristics. This information can be used to optimize micro heat pipe design with respect to length, hydraulic diameter, and number of pipes. Work is progressing on the fabrication of liquid-metal micro heat pipes. In order to be compatible with liquid metal (sodium or potassium), the inside of the micro heat pipes will be coated with a refractory metal (such as tungsten, molybdenum, or titanium).

SNAP-8 refractory boiler development program

NASA Technical Reports Server (NTRS)

Fuller, R. A.

1974-01-01

Performance and endurance tests of the SNAP-8, SN-1 refractory metal boiler are described. The tests were successful and indicated that the boiler heat transfer area could be reduced significantly primarily because of the wetting characteristics of mercury on tantalum in a contaminant-free environment. A continuous endurance test of more than 10,000 hours was conducted without noticeable change in the thermal performance of the boiler. A conclusion of the metallographic examination of the boiler following the endurance test was that expected boiler life would be of the order of 40,000 hours at observed corrosion rates.

Alectinib in Crizotinib-Refractory ALK-Rearranged Non-Small-Cell Lung Cancer: A Phase II Global Study.

PubMed

Ou, Sai-Hong Ignatius; Ahn, Jin Seok; De Petris, Luigi; Govindan, Ramaswamy; Yang, James Chih-Hsin; Hughes, Brett; Lena, Hervé; Moro-Sibilot, Denis; Bearz, Alessandra; Ramirez, Santiago Viteri; Mekhail, Tarek; Spira, Alexander; Bordogna, Walter; Balas, Bogdana; Morcos, Peter N; Monnet, Annabelle; Zeaiter, Ali; Kim, Dong-Wan

2016-03-01

Crizotinib confers improved progression-free survival compared with chemotherapy in anaplastic lymphoma kinase (ALK)-rearranged non-small-cell lung cancer (NSCLC), but progression invariably occurs. We investigated the efficacy and safety of alectinib, a potent and selective ALK inhibitor with excellent CNS penetration, in patients with crizotinib-refractory ALK-positive NSCLC. Alectinib 600 mg was administered orally twice daily. The primary end point was objective response rate (ORR) by central independent review committee (IRC). Of the 138 patients treated, 84 patients (61%) had CNS metastases at baseline, and 122 were response evaluable (RE) by IRC. ORR by IRC was 50% (95% CI, 41% to 59%), and the median duration of response (DOR) was 11.2 months (95% CI, 9.6 months to not reached). In 96 patients (79%) previously treated with chemotherapy, the ORR was 45% (95% CI, 35% to 55%). Median IRC-assessed progression-free survival for all 138 patients was 8.9 months (95% CI, 5.6 to 11.3 months). CNS disease control rate was 83% (95% CI, 74% to 91%), and the median CNS DOR was 10.3 months (95% CI, 7.6 to 11.2 months). CNS ORR in 35 patients with baseline measurable CNS lesions was 57% (95% CI, 39% to 74%). Of the 23 patients with baseline CNS metastases (measurable or nonmeasurable) and no prior radiation, 10 (43%) had a complete CNS response. At 12 months, the cumulative CNS progression rate (24.8%) was lower than the cumulative non-CNS progression rate (33.2%) for all patients. Common adverse events were constipation (33%), fatigue (26%), and peripheral edema (25%); most were grade 1 to 2. Alectinib is highly active and well tolerated in patients with advanced, crizotinib-refractory ALK-positive NSCLC, including those with CNS metastases. © 2015 by American Society of Clinical Oncology.

Brazing of refractory, superalloy, and composite materials for Space Shuttle applications.

NASA Technical Reports Server (NTRS)

Beuyukian, C. S.

1972-01-01

Research work concerning the metallic portion of the shuttle-orbiter heat shield (expected to experience temperatures up to 2500 F) is described. The five metals being evaluated are TD-Ni-Cr, Cb-C129Y, Cb752, Hayes 188, and Inconel 625. Brazing techniques whereby pairs of these materials are joined into thin-membered assemblies for heat shield applications are described. Results obtained with the vacuum-furnace brazing process are examined. In addition, the use of brazed aluminum-boron metal-matrix-contoured composite structures for heat shield applications is evaluated.

IMPROVED CORROSION RESISTANCE OF ALUMINA REFRACTORIES

DOE Office of Scientific and Technical Information (OSTI.GOV)

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 thismore » 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.« less

Vertical feed stick wood fuel burning furnace system

DOEpatents

Hill, Richard C.

1982-01-01

A stove or furnace for efficient combustion of wood fuel includes a vertical feed combustion chamber (15) for receiving and supporting wood fuel in a vertical attitude or stack. A major upper portion of the combustion chamber column comprises a water jacket (14) for coupling to a source of water or heat transfer fluid for convection circulation of the fluid. The locus (31) of wood fuel combustion is thereby confined to the refractory base of the combustion chamber. A flue gas propagation delay channel (34) extending laterally from the base of the chamber affords delayed travel time in a high temperature refractory environment sufficient to assure substantially complete combustion of the gaseous products of wood burning with forced air prior to extraction of heat in heat exchanger (16). Induced draft draws the fuel gas and air mixture laterally through the combustion chamber and refractory high temperature zone to the heat exchanger and flue. Also included are active sources of forced air and induced draft, multiple circuit couplings for the recovered heat, and construction features in the refractory material substructure and metal component superstructure.

Rates and Durability of Response to Salvage Radiation Therapy Among Patients With Refractory or Relapsed Aggressive Non-Hodgkin Lymphoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tseng, Yolanda D., E-mail: ydt2@uw.edu; Chen, Yu-Hui; Catalano, Paul J.

Purpose: To evaluate the response rate (RR) and time to local recurrence (TTLR) among patients who received salvage radiation therapy for relapsed or refractory aggressive non-Hodgkin lymphoma (NHL) and investigate whether RR and TTLR differed according to disease characteristics. Methods and Materials: A retrospective review was performed for all patients who completed a course of salvage radiation therapy between January 2001 and May 2011 at Brigham and Women's Hospital/Dana-Farber Cancer Institute. Separate analyses were conducted for patients treated with palliative and curative intent. Predictors of RR for each subgroup were assessed using a generalized estimating equation model. For patients treatedmore » with curative intent, local control (LC) and progression-free survival were estimated with the Kaplan-Meier method; predictors for TTLR were evaluated using a Cox proportional hazards regression model. Results: Salvage radiation therapy was used to treat 110 patients to 121 sites (76 curative, 45 palliative). Salvage radiation therapy was given as part of consolidation in 18% of patients treated with curative intent. Median dose was 37.8 Gy, with 58% and 36% of curative and palliative patients, respectively, receiving 39.6 Gy or higher. The RR was high (86% curative, 84% palliative). With a median follow-up of 4.8 years among living patients, 5-year LC and progression-free survival for curative patients were 66% and 34%, respectively. Refractory disease (hazard ratio 3.3; P=.024) and lack of response to initial chemotherapy (hazard ratio 4.3; P=.007) but not dose (P=.93) were associated with shorter TTLR. Despite doses of 39.6 Gy or higher, 2-year LC was only 61% for definitive patients with refractory disease or disease that did not respond to initial chemotherapy. Conclusions: Relapsed or refractory aggressive NHL is responsive to salvage radiation therapy, and durable LC can be achieved in some cases. However, refractory disease is associated with a shorter TTLR, suggesting that radiation dose escalation, addition of radiosensitizers, or a combination of both may be indicated in these patients.« less

Coatings for aircraft gas turbine engines and space shuttle heat shields: A review of Lewis Research Center programs

NASA Technical Reports Server (NTRS)

Grisaffe, S. J.; Merutka, J. P.

1972-01-01

The status of several coating programs is reviewed. These include efforts on protecting aircraft gas turbine engine materials from oxidation/corrosion and on protecting refractory metal reentry heat shields from oxidation.

Dry soldering with hot filament produced atomic hydrogen

DOEpatents

Panitz, Janda K. G.; Jellison, James L.; Staley, David J.

1995-01-01

A system for chemically transforming metal surface oxides to metal that is especially, but not exclusively, suitable for preparing metal surfaces for dry soldering and solder reflow processes. The system employs one or more hot, refractory metal filaments, grids or surfaces to thermally dissociate molecular species in a low pressure of working gas such as a hydrogen-containing gas to produce reactive species in a reactive plasma that can chemically reduce metal oxides and form volatile compounds that are removed in the working gas flow. Dry soldering and solder reflow processes are especially applicable to the manufacture of printed circuit boards, semiconductor chip lead attachment and packaging multichip modules. The system can be retrofitted onto existing metal treatment ovens, furnaces, welding systems and wave soldering system designs.

Effects of Temperature, Oxygen Partial Pressure, and Materials Selection on Slag Infiltration into Porous Refractories for Entrained-Flow Gasifiers

NASA Astrophysics Data System (ADS)

Kaneko, Tetsuya Kenneth

The penetration rate of molten mineral contents (slag) from spent carbonaceous feedstock into porous ceramic-oxide refractory linings is a critical parameter in determining the lifecycle of integrated gasification combined cycle energy production plants. Refractory linings that withstand longer operation without interruption are desirable because they can mitigate consumable and maintenance costs. Although refractory degradation has been extensively studied for many other high-temperature industrial processes, this work focuses on the mechanisms that are unique to entrained-flow gasification systems. The use of unique feedstock mixtures, temperatures from 1450 °C to 1600 °C, and oxygen partial pressures from 10-7 atm to 10-9 atm pose engineering challenges in designing an optimal refractory material. Experimentation, characterization, and modeling show that gasifier slag infiltration into porous refractory is determined by interactions between the slag and the refractory that either form a physical barrier that impedes fluid flow or induce an increased fluid viscosity that decelerates the velocity of the fluid body. The viscosity of the slag is modified by the thermal profile of the refractory along the penetration direction as well as reactions between the slag and refractory that alter the chemistry, and thereby the thermo-physical properties of the fluid. Infiltration experiments reveal that the temperature gradient inherently present along the refractory lining limits penetration. A refractory in near-isothermal conditions demonstrates deeper slag penetration as compared to one that experiences a steeper thermal profile. The decrease in the local temperatures of the slag as it travels deeper into the refractory increases the viscosity of the fluid, which in turn slows the infiltration velocity of fluid body into the pores of the refractory microstructure. With feedstock mixtures that exhibit high iron-oxide concentrations, a transition-metal-oxide, the oxygen partial pressure of the operating atmosphere regulates the penetration of slag into refractory. The viscosity of the slag, which dictates its penetration rate, is influenced by the oxidation state of the Fe cation. Slag penetrations are shallower in oxidizing conditions than they are in reducing conditions because the iron-oxide from the slag solutions into the corundum-structured refractory and the slag is depleted of iron-oxide, increasing the viscosity of slags. Equally, the chemistries of both the refractory and slag materials dictate the course of penetration. Cr2O3-Al2O3 refractory limits mixed feedstock slag penetration through formation of a chromium spinel layer that functions as a physical obstacle against fluid flow. Al2O 3-SiO2 refractory limits eastern coal feedstock slag penetration as a result of refractory dissolution of SiO2, which increases the viscosity of slags. A physical model, which considers unidirectional fluid flow of slag through each pore of the porous microstructure of the refractory, sufficiently approximates the penetration depth of the slag into the refractory. Agreement between experiments and the physical model demonstrates that the slag is driven into the refractory by capillary pressure. Since the viscosity of the slag continuously changes as the slag travels through the inherent temperature gradient of the refractory lining, the model incorporates dynamic viscosities that are dependent on both temperature and composition to project depths that are unique to the experimental parameters. The significantly different length scales of the radial and penetration directions of the pores allows for the application of a lubrication approximation onto the momentum equation. This process produces an analytical solution that effectively envelopes the variable viscosity into a single term.

Supported molten-metal catalysts

DOEpatents

Datta, Ravindra; Singh, Ajeet; Halasz, Istvan; Serban, Manuela

2001-01-01

An entirely new class of catalysts called supported molten-metal catalysts, SMMC, which can replace some of the existing precious metal catalysts used in the production of fuels, commodity chemicals, and fine chemicals, as well as in combating pollution. SMMC are based on supporting ultra-thin films or micro-droplets of the relatively low-melting (<600.degree. C.), inexpensive, and abundant metals and semimetals from groups 1, 12, 13, 14, 15 and 16, of the periodic table, or their alloys and intermetallic compounds, on porous refractory supports, much like supported microcrystallites of the traditional solid metal catalysts. It thus provides orders of magnitude higher surface area than is obtainable in conventional reactors containing molten metals in pool form and also avoids corrosion. These have so far been the chief stumbling blocks in the application of molten metal catalysts.

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

NASA Astrophysics Data System (ADS)

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.

Thermophotovoltaic energy conversion using photonic bandgap selective emitters

DOEpatents

Gee, James M.; Lin, Shawn-Yu; Fleming, James G.; Moreno, James B.

2003-06-24

A method for thermophotovoltaic generation of electricity comprises heating a metallic photonic crystal to provide selective emission of radiation that is matched to the peak spectral response of a photovoltaic cell that converts the radiation to electricity. The use of a refractory metal, such as tungsten, for the photonic crystal enables high temperature operation for high radiant flux and high dielectric contrast for a full 3D photonic bandgap, preferable for efficient thermophotovoltaic energy conversion.

Feasibility Study for Casting of High Temperature Refractory Superalloy Composites

NASA Technical Reports Server (NTRS)

Lee, Jonathan A.

1998-01-01

Abstract This study investigated the feasibility of using conventional casting technique to fabricate refractory wires reinforced superalloy composites. These composites were being developed for advanced rocket engine turbine blades and other high temperature applications operating up to 2000 F. Several types of refractory metal wires such as W- Th, W-Re, Mo-Hf-C and W-HF-C reinforced waspaloy were experimentally cast and heat treated at 2000 F up to 48 hrs. Scanning electron microscope analysis was conducted in regions adjacent to the wire-matrix interface to determine the reaction zone and chemical compatibility resulting from material interdiffusion. It was concluded that fabrication using conventional casting may be feasible because the wire-matrix reaction zone thickness was comparable to similar composites produced by arc-sprayed monotape with hot isostatic pressing technique, Moreover, it was also found that the chemical compatibility could be improved significantly through a slight modification of the superalloy matrix compositions.

Favorable outcome of early treatment of new onset child and adolescent migraine-implications for disease modification.

PubMed

Charles, James A; Peterlin, B L; Rapoport, Alan M; Linder, Steven L; Kabbouche, Marielle A; Sheftell, Fred D

2009-08-01

There is evidence that the prevalence of migraine in children and adolescents may be increasing. Current theories of migraine pathophysiology in adults suggest activation of central cortical and brainstem pathways in conjunction with the peripheral trigeminovascular system, which ultimately results in release of neuropeptides, facilitation of central pain pathways, neurogenic inflammation surrounding peripheral vessels, and vasodilatation. Although several risk factors for frequent episodic, chronic, and refractory migraine have been identified, the causes of migraine progression are not known. Migraine pathophysiology has not been fully evaluated in children. In this review, we will first discuss the evidence that early therapeutic interventions in the child or adolescent new onset migraineur, may halt or limit progression and disability. We will then review the evidence suggesting that many adults with chronic or refractory migraine developed their migraine as children or adolescents and may not have been treated adequately with migraine-specific therapy. Finally, we will show that early, appropriate and optimal treatment of migraine during childhood and adolescence may result in disease modification and prevent progression of this disease.

Ibrutinib for patients with rituximab-refractory Waldenström's macroglobulinaemia (iNNOVATE): an open-label substudy of an international, multicentre, phase 3 trial.

PubMed

Dimopoulos, Meletios A; Trotman, Judith; Tedeschi, Alessandra; Matous, Jeffrey V; Macdonald, David; Tam, Constantine; Tournilhac, Olivier; Ma, Shuo; Oriol, Albert; Heffner, Leonard T; Shustik, Chaim; García-Sanz, Ramón; Cornell, Robert F; de Larrea, Carlos Fernández; Castillo, Jorge J; Granell, Miquel; Kyrtsonis, Marie-Christine; Leblond, Veronique; Symeonidis, Argiris; Kastritis, Efstathios; Singh, Priyanka; Li, Jianling; Graef, Thorsten; Bilotti, Elizabeth; Treon, Steven; Buske, Christian

2017-02-01

In the era of widespread rituximab use for Waldenström's macroglobulinaemia, new treatment options for patients with rituximab-refractory disease are an important clinical need. Ibrutinib has induced durable responses in previously treated patients with Waldenström's macroglobulinaemia. We assessed the efficacy and safety of ibrutinib in a population with rituximab-refractory disease. This multicentre, open-label substudy was done at 19 sites in seven countries in adults aged 18 years and older with confirmed Waldenström's macroglobulinaemia, refractory to rituximab and requiring treatment. Disease refractory to the last rituximab-containing therapy was defined as either relapse less than 12 months since last dose of rituximab or failure to achieve at least a minor response. Key exclusion criteria included: CNS involvement, a stroke or intracranial haemorrhage less than 12 months before enrolment, clinically significant cardiovascular disease, hepatitis B or hepatitis C viral infection, and a known bleeding disorder. Patients received oral ibrutinib 420 mg once daily until progression or unacceptable toxicity. The substudy was not prospectively powered for statistical comparisons, and as such, all the analyses are descriptive in nature. This study objectives were the proportion of patients with an overall response, progression-free survival, overall survival, haematological improvement measured by haemoglobin, time to next treatment, and patient-reported outcomes according to the Functional Assessment of Cancer Therapy-Anemia (FACT-An) and the Euro Qol 5 Dimension Questionnaire (EQ-5D-5L). All analyses were per protocol. The study is registered at ClinicalTrials.gov, number NCT02165397, and follow-up is ongoing but enrolment is complete. Between Aug 18, 2014, and Feb 18, 2015, 31 patients were enrolled. Median age was 67 years (IQR 58-74); 13 (42%) of 31 patients had high-risk disease per the International Prognostic Scoring System Waldenström Macroglobulinaemia, median number of previous therapies was four (IQR 2-6), and all were rituximab-refractory. At a median follow-up of 18·1 months (IQR 17·5-18·9), the proportion of patients with an overall response was 28 [90%] of 31 (22 [71%] of patients had a major response), the estimated 18 month progression-free survival rate was 86% (95% CI 66-94), and the estimated 18 month overall survival rate was 97% (95% CI 79-100). Baseline median haemoglobin of 10·3 g/dL (IQR 9·3-11·7) increased to 11·4 g/dL (10·9-12·4) after 4 weeks of ibrutinib treatment and reached 12·7 g/dL (11·8-13·4) at week 49. A clinically meaningful improvement from baseline in FACT-An score, anaemia subscale score, and the EQ-5D-5L were reported at all post-baseline visits. Time to next treatment will be presented at a later date. Common grade 3 or worse adverse events included neutropenia in four patients (13%), hypertension in three patients (10%), and anaemia, thrombocytopenia, and diarrhoea in two patients each (6%). Serious adverse events occurred in ten patients (32%) and were most often infections. Five (16%) patients discontinued ibrutinib: three due to progression and two due to adverse events, while the remaining 26 [84%] of patients are continuing ibrutinib at the time of this report. The sustained responses and median progression-free survival time, combined with a manageable toxicity profile observed with single-agent ibrutinib indicate that this chemotherapy-free approach is a potential new treatment choice for patients who had heavily pretreated, rituximab-refractory Waldenström's macroglobulinaemia. Pharmacyclics LLC, an AbbVie Company. Copyright © 2017 Elsevier Ltd. All rights reserved.

40 CFR 471.51 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2014 CFR

2014-07-01

...) Molten salt rinse. Subpart E—BPT Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average mg/off-kg (pounds per million off-pounds) of refractory metals treated with molten salt...

40 CFR 471.51 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2012 CFR

2012-07-01

...) Molten salt rinse. Subpart E—BPT Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average mg/off-kg (pounds per million off-pounds) of refractory metals treated with molten salt...

Creep and Oxidation of Hafnium Diboride Based Ultra High Temperature Ceramics at 1500C

DTIC Science & Technology

2015-12-01

through experimentation. Although the Literature Review showed that some theories and models have been developed based on extensive experimental results...of Some Refractory Metals & Ceramics [Fahrenholtz] ........... 14 Figure 4: Creep Strain vs Time Based on Burgers Model ...

Analysis of the chemical and physical properties of combustion aerosols: Properties overview

EPA Science Inventory

Aerosol chemical composition is remarkably complex. Combustion aerosols can comprise tens of thousands of organic compounds and fragments, refractory carbon, metals, cations, anions, salts, and other inorganic phases and substituents [Hays et al., 2004]. Aerosol organic matter no...

[The last phase in the progressive neoplasic disease: care at the end-of-life, refractory symptoms and sedation].

PubMed

González Barón, Manuel; Gómez Raposo, César; Vilches Aguirre, Yolanda

2006-09-23

End-of-life is one of the most stressful phases during course of a neoplasic disease. Frequently, death of patients with cancer comes after a continuous and progressive physical impairment. As death approaches, the medical team might redefine outcomes and treat as priority symptoms and relief suffering. That care encompasses the physical, psychological, social, spiritual, and existential needs of patients and their families. However, symptoms are frequently observed that are intolerable for the patient and which do not respond to usual palliative measures. The intolerable nature and being refractory to treatment indicates to the health-care team, on many occasions, the need for sedation of the patient. The medical team can take comfort in the knowledge that they did their best to provide safe passage to all their patients and that, although they did not always cure them, the patients often were healed.

Research in progress: Medical Research Council United Kingdom Refractory Asthma Stratification Programme (RASP-UK).

PubMed

Heaney, Liam G; Djukanovic, Ratko; Woodcock, Ashley; Walker, Samantha; Matthews, John G; Pavord, Ian D; Bradding, Peter; Niven, Robert; Brightling, Chris E; Chaudhuri, Rekha; Arron, Joseph R; Choy, David F; Cowan, Douglas; Mansur, Adel; Menzies-Gow, Andrew; Adcock, Ian; Chung, Kian F; Corrigan, Chris; Coyle, Peter; Harrison, Timothy; Johnston, Sebastian; Howarth, Peter; Lordan, James; Sabroe, Ian; Bigler, Jeannette; Smith, Dirk; Catley, Matthew; May, Richard; Pierre, Lisa; Stevenson, Chris; Crater, Glenn; Keane, Frank; Costello, Richard W; Hudson, Val; Supple, David; Hardman, Tim

2016-02-01

The UK Refractory Asthma Stratification Programme (RASP-UK) will explore novel biomarker stratification strategies in severe asthma to improve clinical management and accelerate development of new therapies. Prior asthma mechanistic studies have not stratified on inflammatory phenotype and the understanding of pathophysiological mechanisms in asthma without Type 2 cytokine inflammation is limited. RASP-UK will objectively assess adherence to corticosteroids (CS) and examine a novel composite biomarker strategy to optimise CS dose; this will also address what proportion of patients with severe asthma have persistent symptoms without eosinophilic airways inflammation after progressive CS withdrawal. There will be interactive partnership with the pharmaceutical industry to facilitate access to stratified populations for novel therapeutic studies. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Fabrication of Smooth Patterned Structures of Refractory Metals, Semiconductors, and Oxides via Template Stripping

PubMed Central

2013-01-01

The template-stripping method can yield smooth patterned films without surface contamination. However, the process is typically limited to coinage metals such as silver and gold because other materials cannot be readily stripped from silicon templates due to strong adhesion. Herein, we report a more general template-stripping method that is applicable to a larger variety of materials, including refractory metals, semiconductors, and oxides. To address the adhesion issue, we introduce a thin gold layer between the template and the deposited materials. After peeling off the combined film from the template, the gold layer can be selectively removed via wet etching to reveal a smooth patterned structure of the desired material. Further, we demonstrate template-stripped multilayer structures that have potential applications for photovoltaics and solar absorbers. An entire patterned device, which can include a transparent conductor, semiconductor absorber, and back contact, can be fabricated. Since our approach can also produce many copies of the patterned structure with high fidelity by reusing the template, a low-cost and high-throughput process in micro- and nanofabrication is provided that is useful for electronics, plasmonics, and nanophotonics. PMID:24001174

Examination of nanosecond laser melting thresholds in refractory metals by shear wave acoustics

NASA Astrophysics Data System (ADS)

Abdullaev, A.; Muminov, B.; Rakhymzhanov, A.; Mynbayev, N.; Utegulov, Z. N.

2017-07-01

Nanosecond laser pulse-induced melting thresholds in refractory (Nb, Mo, Ta and W) metals are measured using detected laser-generated acoustic shear waves. Obtained melting threshold values were found to be scaled with corresponding melting point temperatures of investigated materials displaying dissimilar shearing behavior. The experiments were conducted with motorized control of the incident laser pulse energies with small and uniform energy increments to reach high measurement accuracy and real-time monitoring of the epicentral acoustic waveforms from the opposite side of irradiated sample plates. Measured results were found to be in good agreement with numerical finite element model solving coupled elastodynamic and thermal conduction governing equations on structured quadrilateral mesh. Solid-melt phase transition was handled by means of apparent heat capacity method. The onset of melting was attributed to vanished shear modulus and rapid radial molten pool propagation within laser-heated metal leading to preferential generation of transverse acoustic waves from sources surrounding the molten mass resulting in the delay of shear wave transit times. Developed laser-based technique aims for applications involving remote examination of rapid melting processes of materials present in harsh environment (e.g. spent nuclear fuels) with high spatio-temporal resolution.

Feasibility and safety of placement of a newly designed, fully covered self-expandable metal stent for refractory benign pancreatic ductal strictures: a pilot study (with video).

PubMed

Park, Do Hyun; Kim, Myung-Hwan; Moon, Sung-Hoon; Lee, Sang Soo; Seo, Dong-Wan; Lee, Sung-Koo

2008-12-01

Painful chronic pancreatitis with main pancreatic ductal strictures is usually managed with endotherapy with a plastic stent. To date, the role of placement of metallic stents, especially uncovered ones in benign pancreatic ductal stricture, has been unsatisfactory as a result of stent dysfunction related to mucosal hyperplasia. We explored the feasibility and safety of temporary placement of a newly designed, fully covered self-expandable metal stent (FCSEMS) in painful chronic pancreatitis and refractory benign pancreatic ductal strictures. A prospective pilot and feasibility study. A tertiary academic center. Thirteen patients with chronic painful pancreatitis of alcoholic (8) or idiopathic (5) etiology. ERCP with temporary FCSEMS placement (2 months). Endoscopic removal of FCSEMSs was performed with a snare or rat-tooth forceps. End points were feasibility, safety, and morbidity. Successful FCSEMS placement was performed in all enrolled patients. After immediate placement of FCSEMS, 2 patients had mild acute pancreatitis related mainly to the stricture dilation procedure (Soehendra stent retriever or balloon dilation). Complications associated with stent placement included 5 migrations (39%, 1 proximal and 4 distal) and 2 incidents of cholestatic liver dysfunction associated with the compression of the bile duct orifice by expansion of FCSEMSs. In 1 patient with proximal migration, the stent was repositioned by an inflated retrieval balloon. Additional endoscopic biliary sphincterotomy with or without biliary stenting was performed in 2 patients with cholestatic liver dysfunction. There was no occurrence of pancreatic sepsis among any patients. FCSEMSs were removed from 9 of 9 patients without stent migration (100% [9/9] as per protocol, and 69% [9/13] as intention to treat, respectively). Improvement or resolution of the pancreatic ductal strictures was confirmed in all 13 patients on follow-up ERCP (2 months after stent placement), regardless of stent migration. Small patient populations without long-term follow-up. Two-month placement of FCSEMSs in patients with refractory benign pancreatic ductal strictures may be feasible and relatively safe. However, stent migration was not uncommon. A further investigation with ideal stent design may therefore be needed before recommending FCSEMSs as a therapeutic option for refractory benign pancreatic ductal strictures.

Thermally Simulated Testing of a Direct-Drive Gas-Cooled Nuclear Reactor

NASA Technical Reports Server (NTRS)

Godfroy, Thomas; Bragg-Sitton, Shannon; VanDyke, Melissa

2003-01-01

This paper describes the concept and preliminary component testing of a gas-cooled, UN-fueled, pin-type reactor which uses He/Xe gas that goes directly into a recuperated Brayton system to produce electricity for nuclear electric propulsion. This Direct-Drive Gas-Cooled Reactor (DDG) is designed to be subcritical under water or wet-sand immersion in case of a launch accident. Because the gas-cooled reactor can directly drive the Brayton turbomachinery, it is possible to configure the system such that there are no external surfaces or pressure boundaries that are refractory metal, even though the gas delivered to the turbine is 1144 K. The He/Xe gas mixture is a good heat transport medium when flowing, and a good insulator when stagnant. Judicious use of stagnant cavities as insulating regions allows transport of the 1144-K gas while keeping all external surfaces below 900 K. At this temperature super-alloys (Hastelloy or Inconel) can be used instead of refractory metals. Super-alloys reduce the technology risk because they are easier to fabricate than refractory metals, we have a much more extensive knowledge base on their characteristics, and, because they have a greater resistance to oxidation, system testing is eased. The system is also relatively simple in its design: no additional coolant pumps, heat exchanger, or freeze-thaw systems are required. Key to success of this concept is a good knowledge of the heat transfer between the fuel pins and the gas, as well as the pressure drop through the system. This paper describes preliminary testing to obtain this key information, as well as experience in demonstrating electrical thermal simulation of reactor components and concepts.

Direct-Drive Gas-Cooled Reactor Power System: Concept and Preliminary Testing

NASA Technical Reports Server (NTRS)

Wright, S. A.; Lipinski, R. J.; Godfroy, T. J.; Bragg-Sitton, S. M.; VanDyke, M. K.

2002-01-01

This paper describes the concept and preliminary component testing of a gas-cooled, UN-fueled, pin-type reactor which uses He/Xe gas that goes directly into a recuperated Brayton system to produce electricity for nuclear electric propulsion. This Direct-Drive Gas-Cooled Reactor (DDG) is designed to be subcritical under water or wet- sand immersion in case of a launch accident. Because the gas-cooled reactor can directly drive the Brayton turbomachinery, it is possible to configure the system such that there are no external surfaces or pressure boundaries that are refractory metal, even though the gas delivered to the turbine is 1144 K. The He/Xe gas mixture is a good heat transport medium when flowing, and a good insulator when stagnant. Judicious use of stagnant cavities as insulating regions allows transport of the 1144-K gas while keeping all external surfaces below 900 K. At this temperature super-alloys (Hastelloy or Inconel) can be used instead of refractory metals. Super-alloys reduce the technology risk because they are easier to fabricate than refractory metals, we have a much more extensive knowledge base on their characteristics, and, because they have a greater resistance to oxidation, system testing is eased. The system is also relatively simple in its design: no additional coolant pumps, heat exchanger, or freeze-thaw systems are required. Key to success of this concept is a good knowledge of the heat transfer between the fuel pins and the gas, as well as the pressure drop through the system. This paper describes preliminary testing to obtain this key information, as well as experience in demonstrating electrically heated testing of simulated reactor components.

Retrospective Analysis of Nonepileptic Patients With Isolated Epileptiform Discharges Treated With Anticonvulsants.

PubMed

Swatzyna, Ronald J; Tarnow, Jay D; Proler, Meyer L; Roark, Alexandra J; MacInerney, Erin K; Kozlowski, Gerald P

2017-09-01

Many antiepileptic drugs (AEDs) have been tested on nonepileptic patients with a variety of diagnoses. The Food and Drug Administration has only approved certain AEDs for a small number of psychiatric conditions. There are few studies of nonepileptic patients that recommend an empirical trial of AEDs when isolated epileptiform discharges (IEDs) are identified in the electroencephalogram (EEG). However, no trials have been published. The purpose of this study is to evaluate the outcome of treating nonepileptic patients with AEDs when IEDs are present. Refractory cases were reviewed from a multidisciplinary practice whose EEG readings contained IEDs and were subsequently medicated with anticonvulsants by the clinic's psychiatrist. The psychiatrist's progress notes were assessed to determine the impact of adding anticonvulsants based on parent reports, teacher reports, and clinical observation. The final sample was composed of 76 refractory cases. Of the 76 patients treated with anticonvulsants, the majority were found to be improved in follow-up progress notes: 65 improved (85.53%), 6 unchanged (7.89%), and 5 more severe (6.58%). These observational findings suggest that further studies will be needed to show that IEDs may predict positive treatment outcome to anticonvulsant medication and act as a step toward an evidence-based treatment. Also, EEG screening may prove to be useful for refractory cases regardless of age, gender, or diagnosis.

Radiotherapy With or Without Surgery for Patients With Idiopathic Sclerosing Orbital Inflammation Refractory or Intolerant to Steroid Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Jong Hoon; Kim, Yeon-Sil, E-mail: yeonkim7@catholic.ac.kr; Yang, Suk Woo

Purpose: To evaluate the outcomes of patients with idiopathic sclerosing orbital inflammation (ISOI) treated with radiotherapy with or without surgery. Methods and Materials: We retrospectively reviewed 22 patients with histopathologically confirmed ISOI who had been refractory or intolerant to steroid therapy and treated with radiation with or without surgery. The radiation dose ranged from 20 to 40 Gy (median, 20 Gy) at 2 Gy per fraction. Presenting signs and treatment outcomes were assessed. Results: Proptosis was the most common sign at presentation, seen in 19 (86.3%) patients, followed by restriction of extraocular movements in 10 (45.4%) patients. Response to radiotherapymore » was complete in 15 (68.1%) patients, partial in 3 (13.6%) patients, and none in 4 (18.2%) patients. At the median follow-up of 34 months, 14 (63.6%) patients had progression-free state of symptoms and signs, with the progression-free duration ranging from 3 to 75 months (median, 41.5 months), whereas 8 (36.4%) patients had recurrent or persistent disease although they had received radiotherapy. Of the 14 progression-free patients, 6 underwent a bimodality treatment of debulking surgery of ocular disease and radiotherapy. They had had no recurrent disease. Cataract was the most common late complications, and 2 patients experienced a Grade 3 cataract. Conclusion: Our study suggests that for patients with ISOI who are refractory or intolerant to steroid therapy, 20 Gy of radiotherapy appears to be effective for the control of disease with acceptable complications, especially when it is combined with surgery.« less

High activity Rhenium-186 HEDP with autologous peripheral blood stem cell rescue: a phase I study in progressive hormone refractory prostate cancer metastatic to bone

PubMed Central

O'Sullivan, J M; McCready, V R; Flux, G; Norman, A R; Buffa, F M; Chittenden, S; Guy, M; Pomeroy, K; Cook, G; Gadd, J; Treleaven, J; Al-Deen, A; Horwich, A; Huddart, R A; Dearnaley, D P

2002-01-01

We tested the feasibility and toxicity of high activities Rhenium-186 hydroxyethylidene diphosphonate, with peripheral blood stem cell rescue in patients with progressive hormone refractory prostate cancer metastatic to bone. Twenty-five patients received between 2500 and 5000 MBq of Rhenium-186 hydroxyethylidene diphosphonate followed 14 days later by the return of peripheral blood peripheral blood stem cells. Activity limiting toxicity was defined as grade III haematological toxicity, lasting at least 7 days, or grade IV haematological toxicity of any duration or any serious unexpected toxicity. Activity limiting toxicity occurred in two of six who received activities of 5000 MBq and maximum tolerated activity was defined at this activity level. Prostate specific antigen reductions of 50% or more lasting at least 4 weeks were seen in five of the 25 patients (20%) all of whom received more than 3500 MBq of Rhenium-186 hydroxyethylidene diphosphonate. The actuarial survival at 1 year is 54%. Administered activities of 5000 MBq of Rhenium-186 hydroxyethylidene diphosphonate are feasible using autologous peripheral blood peripheral blood stem cell rescue in patients with progressive hormone refractory prostate cancer metastatic to bone. The main toxicity is thrombocytopaenia, which is short lasting. A statistically significant activity/prostate specific antigen response was seen. We have now commenced a Phase II trial to further evaluate response rates. British Journal of Cancer (2002) 86, 1715–1720. doi:10.1038/sj.bjc.6600348 www.bjcancer.com © 2002 Cancer Research UK PMID:12087455

Extracorporeal Membrane Oxygenation for Refractory Severe Respiratory Failure in Acute Interstitial Pneumonia.

PubMed

Gonçalves-Venade, Gabriela; Lacerda-Príncipe, Nuno; Roncon-Albuquerque, Roberto; Paiva, José Artur

2018-05-01

Acute interstitial pneumonia (AIP) is a rare idiopathic interstitial lung disease with rapid progressive respiratory failure and high mortality. In the present report, three cases of AIP complicated by refractory respiratory failure supported with extracorporeal membrane oxygenation (ECMO) are presented. One male and two female patients (ages 27-59) were included. Venovenous ECMO support was provided using miniaturized systems, with two-site femoro-jugular circuit configuration. Despite lung protective ventilation, prone position and neuromuscular blockade, refractory respiratory failure of unknown etiology supervened (ratio of arterial oxygen partial pressure to fractional inspired oxygen 46-130) and ECMO was initiated after 3-7 days of mechanical ventilation. AIP diagnosis was established after exclusion of infectious and noninfectious acute respiratory distress syndrome on the basis of clinical and analytical data, bronchoalveolar lavage analysis and lung imaging, with a confirmatory surgical lung biopsy revealing diffuse alveolar damage of unknown etiology. Immunosuppressive treatment consisted in high-dose corticosteroids and cyclophosphamide in one case. Two patients survived to hospital discharge. ECMO allowed AIP diagnosis and treatment in the presence of refractory respiratory failure, therefore reducing ventilator-induced lung injury and bridging lung recovery in two patients. ECMO referral should be considered in refractory respiratory failure if AIP is suspected. © 2018 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

The anti-malarial chloroquine overcomes Primary resistance and restores sensitivity to Trastuzumab in HER2-positive breast cancer

PubMed Central

Cufí, Sílvia; Vazquez-Martin, Alejandro; Oliveras-Ferraros, Cristina; Corominas-Faja, Bruna; Cuyàs, Elisabet; López-Bonet, Eugeni; Martin-Castillo, Begoña; Joven, Jorge; Menendez, Javier A.

2013-01-01

Autophagy may control the de novo refractoriness of HER2 gene-amplified breast carcinomas to the monoclonal antibody trastuzumab (Herceptin). Tumor cells originally obtained from a patient who rapidly progressed on trastuzumab ab initio display increased cellular levels of the LC3-II protein—a finding that correlates with increased numbers of autophagosomes—and decreased levels of the autophagy receptor p62/SQSTM1, a protein selectively degraded by autophagy. Trastuzumab-refractory cells are in a state of “autophagy addiction” because genetic ablation of autophagy-specific genes (ATG8, ATG5, ATG12) notably reduces intrinsic refractoriness to trastuzumab. When the anti-malarial lysosomotropic drug chloroquine impedes autophagic resolution of the accumulation of autophagolysosomes formed in the presence of trastuzumab, cells commit to die by apoptosis. Accordingly, combination treatment with trastuzumab and chloroquine radically suppresses tumor growth by > 90% in a tumor xenograft completely refractory to trastuzumab. Adding chloroquine to trastuzumab-based regimens may therefore improve outcomes among women with autophagy-addicted HER2-positive breast cancer. PMID:23965851

Phase II trial of CH5424802 (alectinib hydrochloride) for recurrent or refractory ALK-positive anaplastic large cell lymphoma: study protocol for a non-randomized non-controlled trial.

PubMed

Nagai, Hirokazu; Fukano, Reiji; Sekimizu, Masahiro; Kada, Akiko; M Saito, Akiko; Asada, Ryuta; Mori, Tetsuya

2017-08-01

Currently, a standard therapy has not been established for recurrent or refractory anaplastic lymphoma kinase-positive anaplastic large cell lymphoma. While there are many treatment options, such as hematopoietic stem cell transplantation, patients with resistant disease to conventional chemotherapies have particularly poor prognosis. There is urgent need to develop new drugs because of the lack of a standard therapy and poor prognoses. This phase II trial is designed for evaluating the efficacy and safety of alectinib hydrochloride for patients with recurrent or refractory anaplastic lymphoma kinase -positive anaplastic large cell lymphoma. The primary endpoint is the response rate according to the Revised Response Criteria for Malignant Lymphoma. The secondary endpoints are pharmacokinetics, safety in children, complete response rate, response duration, progression-free survival, event-free survival, overall survival, and adverse events. The results of this trial will be the pivotal data for the drug approval of alectinib hydrochloride for recurrent or refractory anaplastic lymphoma kinase-positive anaplastic large cell lymphoma.

Gemcitabine, dexamethasone, and cisplatin (GDP) is an effective and well-tolerated salvage therapy for relapsed/refractory diffuse large B-cell lymphoma and Hodgkin lymphoma.

PubMed

Moccia, Alden A; Hitz, Felicitas; Hoskins, Paul; Klasa, Richard; Power, Maryse M; Savage, Kerry J; Shenkier, Tamara; Shepherd, John D; Slack, Graham W; Song, Kevin W; Gascoyne, Randy D; Connors, Joseph M; Sehn, Laurie H

2017-02-01

The optimal choice of salvage therapy for patients with relapsed/refractory diffuse large B-cell lymphoma (DLBCL) or Hodgkin lymphoma (HL) remains unknown. Based on promising results of phase II trials, the preferred salvage regimen in British Columbia since 2002 has been the out-patient regimen, gemcitabine, dexamethasone, and cisplatin (GDP). We conducted a retrospective analysis including all patients with relapsed/refractory DLBCL or HL who received GDP as salvage therapy between September 2002 and June 2010. We identified 235 patients: 152 DLBCL, 83 HL. Overall response rates were 49% and 71% for patients with DLBCL and HL, respectively. Within the transplant-eligible population, 52% of patients with DLBCL and 96% of patients with HL proceeded to stem cell transplantation. The 2-year progression-free survival and overall survival were 21% and 28% in the DLBCL cohort, and 58% and 85% in the HL group. GDP is an effective and well-tolerated out-patient salvage regimen for relapsed/refractory DLBCL and HL.

The anti-malarial chloroquine overcomes primary resistance and restores sensitivity to trastuzumab in HER2-positive breast cancer.

PubMed

Cufí, Sílvia; Vazquez-Martin, Alejandro; Oliveras-Ferraros, Cristina; Corominas-Faja, Bruna; Cuyàs, Elisabet; López-Bonet, Eugeni; Martin-Castillo, Begoña; Joven, Jorge; Menendez, Javier A

2013-01-01

Autophagy may control the de novo refractoriness of HER2 gene-amplified breast carcinomas to the monoclonal antibody trastuzumab (Herceptin). Tumor cells originally obtained from a patient who rapidly progressed on trastuzumab ab initio display increased cellular levels of the LC3-II protein--a finding that correlates with increased numbers of autophagosomes--and decreased levels of the autophagy receptor p62/SQSTM1, a protein selectively degraded by autophagy. Trastuzumab-refractory cells are in a state of "autophagy addiction" because genetic ablation of autophagy-specific genes (ATG8, ATG5, ATG12) notably reduces intrinsic refractoriness to trastuzumab. When the anti-malarial lysosomotropic drug chloroquine impedes autophagic resolution of the accumulation of autophagolysosomes formed in the presence of trastuzumab, cells commit to die by apoptosis. Accordingly, combination treatment with trastuzumab and chloroquine radically suppresses tumor growth by > 90% in a tumor xenograft completely refractory to trastuzumab. Adding chloroquine to trastuzumab-based regimens may therefore improve outcomes among women with autophagy-addicted HER2-positive breast cancer.

Radioactive particles released to the environment from the Fukushima reactors-Confirmation is still needed.

PubMed

Salbu, Brit; Lind, Ole Christian

2016-10-01

After severe nuclear events, a major fraction of refractory radionuclides such as U and Pu are released to the environment in the form of radioactive particles. After the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, Pu isotope ratio signals different from that of global fallout have been reported, indicating that spent fuel particles have been released from the reactors or reactor vessels. Radioactive particles containing (37) Cs and other volatile radionuclides, as well as a series of stable refractory metals (Cs, Fe, Zn, U, etc.), have been identified by several authors claiming that these particles originated from the FDNPP fuel. If so, long-lived radioactive isotopes of the refractory metals should have been identified in these particles. It is therefore most probable that volatile radionuclides released as gases during the accidents have deposited on available surfaces such as fly ash, forming condensation particles during release or transport. If spent fuel particles have been deposited in the FDNPP surroundings, information on particle characteristics influencing ecosystem transport, uptake, and effects is essential for assessing environmental impact and risk. More emphasis should therefore be put on the identification of hot spots in the FDNPP environment followed by the characterization of radioactive particles using nanoanalytical-microanalytical techniques to support environmental monitoring, as recommended in the present study. Integr Environ Assess Manag 2016;12:687-689. © 2016 SETAC. © 2016 SETAC.

Analysis of Supercritical-Extracted Chelated Metal Ions From Mixed Organic-Inorganic Samples

NASA Technical Reports Server (NTRS)

Sinha, Mahadeva P. (Inventor)

1996-01-01

Organic and inorganic contaminants of an environmental sample are analyzed by the same GC-MS instrument by adding an oxidizing agent to the sample to oxidize metal or metal compounds to form metal ions. The metal ions are converted to chelate complexes and the chelate complexes are extracted into a supercritical fluid such as CO2. The metal chelate extract after flowing through a restrictor tube is directly injected into the ionization chamber of a mass spectrometer, preferably containing a refractory metal filament such as rhenium to fragment the complex to release metal ions which are detected. This provides a fast, economical method for the analysis of metal contaminants in a sample and can be automated. An organic extract of the sample in conventional or supercritical fluid solvents can be detected in the same mass spectrometer, preferably after separation in a supercritical fluid chromatograph.

Selinexor in Treating Patients With Abiraterone Acetate and/or Enzalutamide Refractory Metastatic Castration-Resistant Prostate Cancer

ClinicalTrials.gov

2018-05-29

Castration Levels of Testosterone; Hormone-Resistant Prostate Cancer; Metastatic Prostate Carcinoma in the Soft Tissue; Prostate Carcinoma Metastatic in the Bone; PSA Progression; Stage IV Prostate Adenocarcinoma AJCC v7

One step HIP canning of powder metallurgy composites

NASA Technical Reports Server (NTRS)

Juhas, John J. (Inventor)

1990-01-01

A single step is relied on in the canning process for hot isostatic pressing (HIP) powder metallurgy composites. The binders are totally removed while the HIP can of compatible refractory metal is sealed at high vacuum and temperature. This eliminates outgassing during hot isostatic pressing.

Maritime Cast Shop Integrated Improvement Plan

DTIC Science & Technology

2010-08-20

preclude increasing non-value added revert inventory. A second best practice in this area is the consumption and reuse of revert produced from pigging...alloy elements–minimize metallic oxidation.  Inert gas cost—maximize nitrogen use instead of the more costly argon gas use.  Refractory consumption

Removable Mandrels For Vacuum-Plasma-Spray Forming

NASA Technical Reports Server (NTRS)

Krotz, Phillip D.; Davis, William M.; Power, Christopher A.; Woodford, William H.; Todd, Douglas M.; Liaw, Yoon K.; Holmes, Richard R.; Zimmerman, Frank R.; Mckechnie, Timothy N.

1995-01-01

Improved mandrels developed for use in vacuum-plasma-spray (VPS) forming of refractory metal and ceramic furnace cartridge tubes. Designed so after tubes formed on them by VPS, mandrels shrink away from tubes upon cooling back to room temperature and simply slip out of tube.

Development of high temperature nickel-base alloys for jet engine turbine bucket applications

NASA Technical Reports Server (NTRS)

Quigg, R. J.; Scheirer, S. T.

1965-01-01

A program has been initiated to develop a material with superior properties at elevated temperatures for utilization in turbine blade applications. A nickel-base superalloy can provide the necessary high temperature strength by using the maximum capability of the three available strengthening mechanisms - intermetallic gamma prime precipitation (Ni3Al), solid solution strengthening with refractory and precious metals, and stable carbide formations through the addition of strong carbide forming elements. A stress rupture test at 2000 deg F and 15,000 psi was formulated to approximate the desired properties. By adding varying amounts of refractory metals (Mo, W and Ta) it was possible to statistically analyze the effects of each in a basic superalloy composition containing fixed amounts of Co, Cr, C, B, Sr, and Ni at three separate levels of AL and Ta. Metallographic analysis correlated with the mechanical properties of the alloys; those with few strengthening phases were weak and ductile and those with excessive amounts of intermetallic phases present in undesirable morphologies were brittle.

Non-Contact Measurements of Creep Properties of Refractory Materials

NASA Technical Reports Server (NTRS)

Lee, Jonghyun; Bradshaw, Richard C.; Hyers, Robert W.; Rogers, Jan R.; Rathz, Thomas J.; Wall, James J.; Choo, Hahn; Liaw, Peter

2006-01-01

State-of-the-art technologies for hypersonic aircraft, nuclear electric/thermal propulsion for spacecraft, and more efficient jet engines are driving ever more demanding needs for high-temperature (>2000 C) materials. At such high temperatures, creep rises as one of the most important design factors to be considered. Since conventional measurement techniques for creep resistance are limited to about 17OO0C, a new technique is in demand for higher temperatures. This paper presents a non-contact method using electrostatic levitation (ESL) which is applicable to both metallic and non-metallic materials. The samples were rotated quickly enough to cause creep deformation by centrifugal acceleration. The deformation of the samples was captured with a high speed camera and then the images were analyzed to estimate creep resistance. Finite element analyses were performed and compared to the experiments to verify the new method. Results are presented for niobium and tungsten, representative refractory materials at 2300 C and 2700 C respectively.

Composites of low-density trialuminides: Particulate and long fiber reinforcements

NASA Technical Reports Server (NTRS)

Kumar, K. S.; Dipietro, M. S.; Brown, S. A.; Whittenberger, J. D.

1992-01-01

An examination of the ternary L1(sub 2) trialuminides, Al66Ti25Mn9, Al67Ti25Cr8, and Al22Ti8Fe3 in compression, bending, and tension revealed that none of these compounds exhibited a desirable balance of strength, ductility, and oxidation resistance. Subsequently, specific quaternary and quinary compositions were cast, homogenized, and isothermally forged. Both, the monolithic material and its particulate reinforced counterparts were examined in compression, three point bend, and tension as a function of temperature, and at high temperatures as a function of strain rate. An alternate approach that was examined in this program to enhance the low temperature damage tolerance of these materials was to incorporate long refractory metal wires in the matrix. In summary, it appears that of the various matrix compositions examined, ternary Al66Ti25Mn9 exhibits the best balance in strength, ductility, and oxidation resistance. Although the idea of refractory metal wire reinforcement is an attractive one, a successful combination remains to be identified.

Comprehensive recovery of gold and base-metal sulfide minerals from a low-grade refractory ore

NASA Astrophysics Data System (ADS)

Li, Wen-juan; Liu, Shuang; Song, Yong-sheng; Wen, Jian-kang; Zhou, Gui-ying; Chen, Yong

2016-12-01

The comprehensive recovery of small amounts of valuable minerals such as gold and base-metal sulfide minerals from a low-grade refractory ore was investigated. The following treatment strategy was applied to a sample of this ore: gold flotation-gold concentrate leaching-lead and zinc flotation from the gold concentrate leaching residue. Closed-circuit trials of gold flotation yielded a gold concentrate that assayed at 40.23 g·t-1 Au with a recovery of 86.25%. The gold concentrate leaching rate was 98.76%. Two variants of lead-zinc flotation from the residue—preferential flotation of lead and zinc and bulk flotation of lead and zinc—were tested using the middling processing method. Foam from the reflotation was returned to the lead rougher flotation or lead-zinc bulk flotation, whereas middlings from reflotation were discarded. Sulfur concentrate was a byproduct. The combined strategy of flotation, leaching, and flotation is recommended for the treatment of this kind of ore.

Vacuum Plasma Spray (VPS) Forming of Solar Thermal Propulsion Components Using Refractory Metals

NASA Technical Reports Server (NTRS)

Zimmerman, Frank R.; Hissam, David A.; Gerrish, Harold P.; Davis, William M.

1999-01-01

The Thermal Spray Laboratory at NASA's Marshall Space Flight Center has developed and demonstrated a fabrication technique using Vacuum Plasma Spray (VPS) to form structural components from a tungsten/rhenium alloy. The components were assembled into an absorber cavity for a fully-functioning, ground test unit of a solar then-nal propulsion engine. The VPS process deposits refractory metal onto a graphite mandrel of the desired shape. The mandrel acts as a male mold, forming the required contour and dimensions of the inside surface of the deposit. Tungsten and tungsten/25% rhenium were used in the development and production of several absorber cavity components. These materials were selected for their high temperature (greater than 25000 C [greater than 4530 F]) strength. Each absorber cavity comprises 3 coaxial shells with two, double-helical flow passages through which the propellant gas flows. This paper describes the processing techniques, design considerations, and process development associated with forming these engine components.

Influence of cobalt, tantaum and tungsten on the high temperature mechanical properties of single crystal nickel-base superalloys. Ph.D. Thesis - Case Western Reserve Univ.

NASA Technical Reports Server (NTRS)

Nathal, M. V.

1984-01-01

For alloys with the baseline refractory metal level of 3 percent Ta and 10 percent W, decreases in Co level from 10 to 0 percent resulted in increased tensile strength and creep resistance. Substitution of W for Ta resulted in decreased creep life at high stresses but improved life at low stresses. Substitution of Ni for Ta caused large reductions in tensile strength and creep resistance, and corresponding increases in ductility. For these alloys with low Ta plus W totals, strength was independent of Co level. The increases in tensile strength with increases in refractory metal content were related to the increases in gamma volume fraction and solid solution hardening. Increases in strength as Co level decreased were considered to be the result of coherency strain hardening from the increased lattice mismatch. Dislocation shear through the gamma-gamma interface is considered to be the rate limiting step in the deformation process.

Magnetohydrodynamic generator electrode

DOEpatents

Marchant, David D.; Killpatrick, Don H.; Herman, Harold; Kuczen, Kenneth D.

1979-01-01

An improved electrode for use as a current collector in the channel of a magnetohydrodynamid (MHD) generator utilizes an elongated monolithic cap of dense refractory material compliantly mounted to the MHD channel frame for collecting the current. The cap has a central longitudinal channel which contains a first layer of porous refractory ceramic as a high-temperature current leadout from the cap and a second layer of resilient wire mesh in contact with the first layer as a low-temperature current leadout between the first layer and the frame. Also described is a monolithic ceramic insulator compliantly mounted to the frame parallel to the electrode by a plurality of flexible metal strips.

Aerodynamic Levitation Reactor Studies of Fluorine Reactions with Refractory Ceramics

DTIC Science & Technology

1981-05-01

Melting Points of Rare-Earth Metals and Rare-Earth Trifluorides . 14 3. Aerodynamic Lavitation Flow Reactor. 15 4 Lanthanutm-Boron-Carbon Ternary Phase...the least volatile fluorides (CaF , SrT and rare-earth trifluorides ) would yield a 10% increase in w* (initially O.O cam) in about 1 hour at 1300K...measurement, and are, therefore, somewhat uncertain. The melting points of the rare-earth metals and their trifluorides are illustrated in Fig. 2. The melting

Dry soldering with hot filament produced atomic hydrogen

DOEpatents

Panitz, J.K.G.; Jellison, J.L.; Staley, D.J.

1995-04-25

A system is disclosed for chemically transforming metal surface oxides to metal that is especially, but not exclusively, suitable for preparing metal surfaces for dry soldering and solder reflow processes. The system employs one or more hot, refractory metal filaments, grids or surfaces to thermally dissociate molecular species in a low pressure of working gas such as a hydrogen-containing gas to produce reactive species in a reactive plasma that can chemically reduce metal oxides and form volatile compounds that are removed in the working gas flow. Dry soldering and solder reflow processes are especially applicable to the manufacture of printed circuit boards, semiconductor chip lead attachment and packaging multichip modules. The system can be retrofitted onto existing metal treatment ovens, furnaces, welding systems and wave soldering system designs. 1 fig.

High-energy, high-rate materials processing

NASA Astrophysics Data System (ADS)

Marcus, H. L.; Bourell, D. L.; Eliezer, Z.; Persad, C.; Weldon, W.

1987-12-01

The increasingly available range of pulsed-power, high energy kinetic storage devices, such as low-inductance pulse-forming networks, compulsators, and homopolar generators, is presently considered as a basis for industrial high energy/high rate (HEHR) processing to accomplish shock hardening, drilling, rapid surface alloying and melting, welding and cutting, transformation hardening, and cladding and surface melting in metallic materials. Time-temperature-transformation concepts furnish the basis for a fundamental understanding of the potential advantages of this direct pulsed power processing. Attention is given to the HEHR processing of a refractory molybdenum alloy, a nickel-base metallic glass, tungsten, titanium aluminides, and metal-matrix composites.

Molybdenite in calcium-aluminum-rich inclusions in the Allende meteorite

NASA Technical Reports Server (NTRS)

Fuchs, L. H.; Blander, M.

1977-01-01

The first observations of molybdenite in a meteorite have been made in two Ca-Al-rich inclusions in the Allende chondrite. The mineral occurs as single individuals completely enclosed in high Ni metal (62-64.5 wt. % Ni). The association with refractories is consistent with thermodynamic calculations which predict that Mo is a high temperature condensate even when nucleation constraints are imposed on the formation of a metal phase. Kinetic factors (including nucleation constraints) appear to have played an important role in the formation of molybdenite and the associated sulfides, magnetite and high nickel metal.

Method of producing silicon. [gas phase reactor multiple injector liquid feed system

NASA Technical Reports Server (NTRS)

Wolf, C. B.; Meyer, T. N. (Inventor)

1980-01-01

A liquid reactant injector assembly suited for the injection of liquid reactant into a high temperature metal reductant vapor and carrier gas stream for the production of metal is presented. The assembly is especially adapted for the continuous production of high purity silicon by the reduction of SiCl4 with sodium. The assembly includes a refractory-lined, hollow metal shell having ten equally-spaced, concentric, radially directed ports provided in the shell and wall. A hydraulic, atomizing type spray nozzle is mounted in each of the ports recessed from the inner wall surface.

Venetoclax-Rituximab in Relapsed or Refractory Chronic Lymphocytic Leukemia.

PubMed

Seymour, John F; Kipps, Thomas J; Eichhorst, Barbara; Hillmen, Peter; D'Rozario, James; Assouline, Sarit; Owen, Carolyn; Gerecitano, John; Robak, Tadeusz; De la Serna, Javier; Jaeger, Ulrich; Cartron, Guillaume; Montillo, Marco; Humerickhouse, Rod; Punnoose, Elizabeth A; Li, Yan; Boyer, Michelle; Humphrey, Kathryn; Mobasher, Mehrdad; Kater, Arnon P

2018-03-22

Venetoclax inhibits BCL2, an antiapoptotic protein that is pathologically overexpressed and that is central to the survival of chronic lymphocytic leukemia cells. We evaluated the efficacy of venetoclax in combination with rituximab in patients with relapsed or refractory chronic lymphocytic leukemia. In this randomized, open-label, phase 3 trial, we randomly assigned 389 patients to receive venetoclax for up to 2 years (from day 1 of cycle 1) plus rituximab for the first 6 months (venetoclax-rituximab group) or bendamustine plus rituximab for 6 months (bendamustine-rituximab group). The trial design did not include crossover to venetoclax plus rituximab for patients in the bendamustine-rituximab group in whom progression occurred. The primary end point was investigator-assessed progression-free survival. After a median follow-up period of 23.8 months, the rate of investigator-assessed progression-free survival was significantly higher in the venetoclax-rituximab group (32 events of progression or death in 194 patients) than in the bendamustine-rituximab group (114 events in 195 patients); the 2-year rates of progression-free survival were 84.9% and 36.3%, respectively (hazard ratio for progression or death, 0.17; 95% confidence interval [CI], 0.11 to 0.25; P<0.001 by the stratified log-rank test). The benefit was maintained across all clinical and biologic subgroups, including the subgroup of patients with chromosome 17p deletion; the 2-year rate of progression-free survival among patients with chromosome 17p deletion was 81.5% in the venetoclax-rituximab group versus 27.8% in the bendamustine-rituximab group (hazard ratio, 0.13; 95% CI, 0.05 to 0.29), and the 2-year rate among those without chromosome 17p deletion was 85.9% versus 41.0% (hazard ratio, 0.19; 95% CI, 0.12 to 0.32). The benefit of venetoclax plus rituximab over bendamustine plus rituximab was confirmed by an independent review committee assessment of progression-free survival and other secondary efficacy end points. The rate of grade 3 or 4 neutropenia was higher in the venetoclax-rituximab group than in the bendamustine-rituximab group, but the rates of grade 3 or 4 febrile neutropenia and infections or infestations were lower with venetoclax than with bendamustine. The rate of grade 3 or 4 tumor lysis syndrome in the venetoclax-rituximab group was 3.1% (6 of 194 patients). Among patients with relapsed or refractory chronic lymphocytic leukemia, venetoclax plus rituximab resulted in significantly higher rates of progression-free survival than bendamustine plus rituximab. (Funded by Genentech and AbbVie; ClinicalTrials.gov number, NCT02005471 .).

A phase 3 randomized controlled trial of the efficacy and safety of atrasentan in men with metastatic hormone-refractory prostate cancer.

PubMed

Carducci, Michael A; Saad, Fred; Abrahamsson, Per-Anders; Dearnaley, David P; Schulman, Claude C; North, Scott A; Sleep, Darryl J; Isaacson, Jeffrey D; Nelson, Joel B

2007-11-01

The objective of this study was to evaluate the efficacy and safety of atrasentan (Xinlay), a selective endothelin-A receptor antagonist, in patients with metastatic hormone-refractory prostate cancer (HRPC). This multinational, double-blind, placebo-controlled trial enrolled 809 men with metastatic HRPC. Patients were randomized 1:1 to receive either atrasentan 10 mg per day or placebo. The primary endpoint was time to disease progression (TTP), which was determined according to radiographic and clinical measures. Analyses of overall survival and changes in biomarkers also were performed. Atrasentan did not reduce the risk of disease progression relative to placebo (hazards ratio, 0.89; 95% confidence interval, 0.76-1.04; P = .136). Most patients progressed radiographically at the first 12-week bone scan without concomitant clinical progression. In exploratory analyses, increases from baseline to final bone alkaline phosphatase (BAP) and prostate-specific antigen (PSA) levels were significantly lower with atrasentan treatment (P < .05 for each). The median time to BAP progression (>/=50% increase from nadir) was twice as long with atrasentan treatment (505 days vs 254 days; P < .01). The delay in time to PSA progression did not reach statistical significance. Atrasentan generally was tolerated well, and the most common adverse events associated with treatment were headache, rhinitis, and peripheral edema, reflecting the vasodilatory and fluid-retention properties of endothelin-A receptor antagonism. Atrasentan did not delay disease progression in men with metastatic HRPC despite evidence of biologic effects on PSA and BAP as markers of disease burden.

Method of making metal matrix composites reinforced with ceramic particulates

DOEpatents

Cornie, James A.; Kattamis, Theodoulos; Chambers, Brent V.; Bond, Bruce E.; Varela, Raul H.

1989-01-01

Composite materials and methods for making such materials are disclosed in which dispersed ceramic particles are at chemical equilibrium with a base metal matrix, thereby permitting such materials to be remelted and subsequently cast or otherwise processed to form net weight parts and other finished (or semi-finished) articles while maintaining the microstructure and mechanical properties (e.g. wear resistance or hardness) of the original composite. The composite materials of the present invention are composed of ceramic particles in a base metal matrix. The ceramics are preferably carbides of titanium, zirconium, tungsten, molybdenum or other refractory metals. The base metal can be iron, nickel, cobalt, chromium or other high temperature metal and alloys thereof. For ferrous matrices, alloys suitable for use as the base metal include cast iron, carbon steels, stainless steels and iron-based superalloys.

Method of making metal matrix composites reinforced with ceramic particulates

DOEpatents

Cornie, J.A.; Kattamis, T.; Chambers, B.V.; Bond, B.E.; Varela, R.H.

1989-08-01

Composite materials and methods for making such materials are disclosed in which dispersed ceramic particles are at chemical equilibrium with a base metal matrix, thereby permitting such materials to be remelted and subsequently cast or otherwise processed to form net weight parts and other finished (or semi-finished) articles while maintaining the microstructure and mechanical properties (e.g. wear resistance or hardness) of the original composite. The composite materials of the present invention are composed of ceramic particles in a base metal matrix. The ceramics are preferably carbides of titanium, zirconium, tungsten, molybdenum or other refractory metals. The base metal can be iron, nickel, cobalt, chromium or other high temperature metal and alloys thereof. For ferrous matrices, alloys suitable for use as the base metal include cast iron, carbon steels, stainless steels and iron-based superalloys. 2 figs.

Production method for making rare earth compounds

DOEpatents

McCallum, R.W.; Ellis, T.W.; Dennis, K.W.; Hofer, R.J.; Branagan, D.J.

1997-11-25

A method of making a rare earth compound, such as a earth-transition metal permanent magnet compound, without the need for producing rare earth metal as a process step, comprises carbothermically reacting a rare earth oxide to form a rare earth carbide and heating the rare earth carbide, a compound-forming reactant (e.g., a transition metal and optional boron), and a carbide-forming element (e.g., a refractory metal) that forms a carbide that is more thermodynamically favorable than the rare earth carbide whereby the rare earth compound (e.g., Nd{sub 2}Fe{sub 14}B or LaNi{sub 5}) and a carbide of the carbide-forming element are formed.

Production method for making rare earth compounds

DOEpatents

McCallum, R. William; Ellis, Timothy W.; Dennis, Kevin W.; Hofer, Robert J.; Branagan, Daniel J.

1997-11-25

A method of making a rare earth compound, such as a earth-transition metal permanent magnet compound, without the need for producing rare earth metal as a process step, comprises carbothermically reacting a rare earth oxide to form a rare earth carbide and heating the rare earth carbide, a compound-forming reactant (e.g. a transition metal and optional boron), and a carbide-forming element (e.g. a refractory metal) that forms a carbide that is more thermodynamically favorable than the rare earth carbide whereby the rare earth compound (e.g. Nd.sub.2 Fe.sub.14 B or LaNi.sub.5) and a carbide of the carbide-forming element are formed.

Dr. John J. Stephens, Jr., metallurgist extraordinaire.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hosking, Floyd Michael

The organizers of the Dr. John J. Stephens, Jr. Memorial Symposium: Deformation and Interfacial Phenomena in Advanced High-Temperature Materials are honoring the memory of Dr. Stephens and his many technical contributions that were accomplished over a relatively brief twenty year career. His research spanned the areas of creep and deformation of metals, dispersion-strengthened alloys and their properties, metal matrix composite materials, processing and properties of refractory metals, joining of ceramic-ceramic and metal-ceramic systems, active braze alloy development, and mechanical modeling of soldered and brazed assemblies. The purpose of this presentation is to highlight his research and engineering accomplishments, particularly duringmore » his professional career at Sandia National Laboratories in Albuquerque, NM.« less

Corrosion assessment of refractory materials for high temperature waste vitrification

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marra, J.C.; Congdon, J.W.; Kielpinski, A.L.

1995-11-01

A variety of vitrification technologies are being evaluated to immobilize radioactive and hazardous wastes following years of nuclear materials production throughout the Department of Energy (DOE) complex. The compositions and physical forms of these wastes are diverse ranging from inorganic sludges to organic liquids to heterogeneous debris. Melt and off-gas products can be very corrosive at the high temperatures required to melt many of these waste streams. Ensuring material durability is required to develop viable treatment processes. Corrosion testing of materials in some of the anticipated severe environments is an important aspect of the materials identification and selection process. Corrosionmore » coupon tests on typical materials used in Joule heated melters were completed using glass compositions with high salt contents. The presence of chloride in the melts caused the most severe attack. In the metal alloys, oxidation was the predominant corrosion mechanism, while in the tested refractory material enhanced dissolution of the refractory into the glass was observed. Corrosion testing of numerous different refractory materials was performed in a plasma vitrification system using a surrogate heterogeneous debris waste. Extensive corrosion was observed in all tested materials.« less

[Extracorporeal photochemotherapy in therapy-refractory subacute lupus].

PubMed

Richard, M A; Saadallah, S; Lefevre, P; Poullin, P; Buscaylet, S; Grob, J J

2002-01-01

Extracorporeal photopheresis is a leukapheresis therapy that uses psoralen and ultraviolet A irradiation. We report the case of a woman with a refractory sub acute lupus which dramatically but transitionally responded to extracorporeal photopheresis. This women, born in 1960, developed erythematous and squamous patches located on face and neckline, associated with hyperpigmented and atrophic lesions on the arms and shoulders. Investigations confirmed the diagnosis of subacute lupus without systemic disease. All lesions progressed, despite all conventional therapies leading to major aesthetic prejudice. Extracorporeal photopheresis was initiated, and after two months, all lesions, including atrophic and healing lesions had regressed, but laboratory abnormalities did not change. Extracorporeal photopheresis was well tolerated. However, treatment was discontinued nine months later, since the cutaneous lesions relapsed. Extracorporeal photopheresis could be efficient in the treatment of cutaneous autoimmune diseases through several immunomodulatory mechanisms. Extracorporeal photopheresis is a potent alternative agent in the therapy of refractory dermatological diseases

Current Standard and Investigational Approaches to the Management of Hormone-Refractory Prostate Cancer

PubMed Central

Mendiratta, Prateek; Armstrong, Andrew J; George, Daniel J

2007-01-01

Prostate cancer is a common cause of death in men and remains incurable in the metastatic setting. In 2004, 2 landmark trials using docetaxel-based chemotherapy, TAX 327 and SWOG 99-16, showed a survival benefit for the first time in metastatic, hormone-refractory prostate cancer. Current research suggests that several distinct mechanisms of androgen-refractory disease may converge in patients with disease progression on androgen deprivation therapy. These findings have identified several potential targets for therapeutic intervention. Current standard and investigational treatment options for this disease are discussed, including chemotherapy and rapidly evolving therapies in phase II/III trials involving antiangiogenic therapies, signal transduction inhibitors, immunomodulatory agents, and nuclear receptor targets. In light of a growing array of treatment options and an increasingly chronic natural history, this review supports a multidisciplinary care approach to these patients, including medical oncologists, urologists, and radiation oncologists, to optimize survival and quality of life. PMID:17387372

Refractory rheumatoid vasculitis

PubMed Central

Kumar, Ashok; Goel, Anshul; Lapsiwala, Mehul; Singhal, Suman

2016-01-01

Systemic rheumatoid vasculitis (SRV) can develop in rheumatoid arthritis of long duration and high disease activity. It most commonly manifests as cutaneous vasculitis and mononeuritis multiplex. This can involve any organ of the body and carries very high mortality. We report a case of a young male who had rheumatoid arthritis for the past 15 years and became refractory to standard drugs and anti-TNF agents. He subsequently developed SRV, which started as mononeuritis multiplex. Disease progressed to result in gangrene of hands and feet despite receiving intravenous cyclophosphamide. Intravenous immunoglobulin and rituximab also could not provide any response. Prolonged ICU stay resulted in critical care neuromyopathy. Central nervous system vasculitis developed even after repeated infusions of intravenous immunoglobulins and at last he died of complications. In this case report, we have presented rare and chronic protracted presentation of rheumatoid vasculitis involving skin, nerves, brain and testis, which was refractory to the recommended therapies. PMID:28031844

40 CFR 471.53 - New source performance standards (NSPS).

Code of Federal Regulations, 2014 CFR

2014-07-01

... TSS 123 97.9 pH (1) (1) 1 Within the range of 7.5 to 10.0 at all times. (p) Molten salt rinse. Subpart... (pounds per million off-pounds) of refractory metals treated with molten salt Copper 0.810 0.386 Nickel 0...

40 CFR 471.53 - New source performance standards (NSPS).

Code of Federal Regulations, 2012 CFR

2012-07-01

... TSS 123 97.9 pH (1) (1) 1 Within the range of 7.5 to 10.0 at all times. (p) Molten salt rinse. Subpart... (pounds per million off-pounds) of refractory metals treated with molten salt Copper 0.810 0.386 Nickel 0...

Practical method of diffusion-welding steel plate in air

NASA Technical Reports Server (NTRS)

Holko, K. H.; Moore, T. J.

1971-01-01

Method is ideal for critical service requirements where parent metal properties are equaled in notch toughness, stress rupture and other characteristics. Welding technique variations may be used on a variety of materials, such as carbon steels, alloy steels, stainless steels, ceramics, and reactive and refractory materials.

Combustion chamber struts can be effectively transpiration cooled

NASA Technical Reports Server (NTRS)

Palmer, G. H.

1966-01-01

Vapor-deposited sintering technique increases the feasible temperature range of transpiration-cooled structural members in combustion chambers. This technique produces a porous mass of refractory metal wires around a combustion chamber structural member. This mass acts as a transpiration-cooled surface for a thick-walled tube.

A non-randomized study in consecutive patients with postcholecystectomy refractory biliary leaks who were managed endoscopically with the use of multiple plastic stents or fully covered self-expandable metal stents (with videos).

PubMed

Canena, Jorge; Liberato, Manuel; Meireles, Liliane; Marques, Inês; Romão, Carlos; Coutinho, António Pereira; Neves, Beatriz Costa; Veiga, Pedro Mota

2015-07-01

Endoscopic management of postcholecystectomy biliary leaks is widely accepted as the treatment of choice. However, refractory biliary leaks after a combination of biliary sphincterotomy and the placement of a large-bore (10F) plastic stent can occur, and the optimal rescue endotherapy for this situation is unclear. To compare the clinical effectiveness of the use of a fully covered self-expandable metal stent (FCSEMS) with the placement of multiple plastic stents (MPS) for the treatment of postcholecystectomy refractory biliary leaks. Prospective study. Two tertiary-care referral academic centers and one general district hospital. Forty consecutive patients with refractory biliary leaks who underwent endoscopic management. Temporary placement of MPS (n = 20) or FCSEMSs (n = 20). Clinical outcomes of endotherapy as well as the technical success, adverse events, need for reinterventions, and prognostic factors for clinical success. Endotherapy was possible in all patients. After endotherapy, closure of the leak was accomplished in 13 patients (65%) who received MPS and in 20 patients (100%) who received FCSEMSs (P = .004). The Kaplan-Meier (log-rank) leak-free survival analysis showed a statistically significant difference between the 2 patient populations (χ(2) [1] = 8.30; P < .01) in favor of the FCSEMS group. Use of <3 plastic stents (P = .024), a plastic stent diameter <20F (P = .006), and a high-grade biliary leak (P = .015) were shown to be significant predictors of treatment failure with MPS. The 7 patients in whom placement of MPS failed were retreated with FCSEMSs, resulting in closure of the leaks in all cases. Non-randomized design. In our series, the results of the temporary placement of FCSEMSs for postcholecystectomy refractory biliary leaks were superior to those from the use of MPS. A randomized study is needed to confirm our results before further recommendations. Copyright © 2015 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

A locus at 7p14.3 predisposes to refractory celiac disease progression from celiac disease.

PubMed

Hrdlickova, Barbara; Mulder, Chris J; Malamut, Georgia; Meresse, Bertrand; Platteel, Mathieu; Kamatani, Yoichiro; Ricaño-Ponce, Isis; van Wanrooij, Roy L J; Zorro, Maria M; Jan Bonder, Marc; Gutierrez-Achury, Javier; Cellier, Christophe; Zhernakova, Alexandra; Nijeboer, Petula; Galan, Pilar; Withoff, Sebo; Lathrop, Mark; Bouma, Gerd; Xavier, Ramnik J; Jabri, Bana; Bensussan, Nadine C; Wijmenga, Cisca; Kumar, Vinod

2018-05-21

Approximately 5% of patients with celiac disease (CeD) do not respond to a gluten-free diet and progress to refractory celiac disease (RCD), a severe progression that is characterized by infiltration of intraepithelial T lymphocytes. Patients with RCD type II (RCDII) show clonal expansions of intraepithelial T lymphocytes that result in a poor prognosis and a high mortality rate through development of aggressive enteropathy-associated T-cell lymphoma. It is not known whether genetic variations play a role in severe progression of CeD to RCDII. We performed the first genome-wide association study to identify the causal genes for RCDII and the molecular pathways perturbed in RCDII. The genome-wide association study was performed in 38 Dutch patients with RCDII, and the 15 independent top-associated single nucleotide polymorphism (SNP) variants (P<5×10) were replicated in 56 independent French and Dutch patients with RCDII. After replication, SNP rs2041570 on chromosome 7 was significantly associated with progression to RCDII (P=2.37×10, odds ratio=2.36) but not with CeD susceptibility. SNP rs2041570 risk allele A was associated with lower levels of FAM188B expression in blood and small intestinal biopsies. Stratification of RCDII biopsies based on rs2041570 genotype showed differential expression of innate immune and antibacterial genes that are expressed in Paneth cells. We have identified a novel SNP associated with the severe progression of CeD to RCDII. Our data suggest that genetic susceptibility to CeD might be distinct from the progression to RCDII and suggest a role for Paneth cells in RCDII progression.

Phase I Trial of Anti-CS1 Monoclonal Antibody Elotuzumab in Combination With Bortezomib in the Treatment of Relapsed/Refractory Multiple Myeloma

PubMed Central

Jakubowiak, Andrzej J.; Benson, Don M.; Bensinger, William; Siegel, David S.D.; Zimmerman, Todd M.; Mohrbacher, Ann; Richardson, Paul G.; Afar, Daniel E.H.; Singhal, Anil K.; Anderson, Kenneth C.

2012-01-01

Purpose To evaluate the maximum-tolerated dose (MTD), safety, and efficacy of elotuzumab in combination with bortezomib in patients with relapsed or relapsed and refractory multiple myeloma (MM). Patients and Methods Elotuzumab (2.5, 5.0, 10, or 20 mg/kg intravenously [IV]) and bortezomib (1.3 mg/m2 IV) were administered on days 1 and 11 and days 1, 4, 8, and 11, respectively, in 21-day cycles by using a 3 + 3 dose-escalation design. Patients with stable disease or better after four cycles could continue treatment until disease progression or unexpected toxicity. Responses were assessed during each cycle by using European Group for Blood and Marrow Transplantation (EBMT) criteria. Results Twenty-eight patients with a median of two prior therapies were enrolled; three patients each received 2.5, 5.0, and 10 mg/kg of elotuzumab and 19 received 20 mg/kg (six during dose escalation and 13 during an expansion phase). No dose-limiting toxicities were observed during cycle 1 of the dose-escalation phase, and the MTD was not reached up to the maximum planned dose of 20 mg/kg. The most frequent grade 3 to 4 adverse events (AEs) were lymphopenia (25%) and fatigue (14%). Two elotuzumab-related serious AEs of chest pain and gastroenteritis occurred in one patient. An objective response (a partial response or better) was observed in 13 (48%) of 27 evaluable patients and in two (67%) of three patients refractory to bortezomib. Median time to progression was 9.46 months. Conclusion The combination of elotuzumab and bortezomib was generally well-tolerated and showed encouraging activity in patients with relapsed/refractory MM. PMID:22291084

A GRP78-Directed Monoclonal Antibody Recaptures Response in Refractory Multiple Myeloma with Extramedullary Involvement.

PubMed

Rasche, Leo; Menoret, Emmanuelle; Dubljevic, Valentina; Menu, Eline; Vanderkerken, Karin; Lapa, Constantin; Steinbrunn, Torsten; Chatterjee, Manik; Knop, Stefan; Düll, Johannes; Greenwood, Deanne L; Hensel, Frank; Rosenwald, Andreas; Einsele, Hermann; Brändlein, Stephanie

2016-09-01

Glucose-regulated protein (GRP) 78 is overexpressed in multiple myeloma, and both its surface expression and its biologic significance as key sensor of the unfolded protein response make GRP78 an ideal candidate for immunotherapeutic intervention. The monoclonal antibody PAT-SM6 targets surface GRP78 and leads to disease stabilization when used as single agent in a clinical trial. In this article, we evaluated expression of GRP78 in relapsed-refractory disease and explored PAT-SM6 therapy in combination regimens. GRP78 expression was immunohistochemically analyzed during disease progression and development of drug resistance throughout different stages of multiple myeloma. Activity of PAT-SM6 was evaluated in combination with anti-multiple myeloma agents lenalidomide, bortezomib, and dexamethasone in vitro Finally, we report on a multiple myeloma patient with relapsed-refractory disease treated with PAT-SM6 in combination with bortezomib and lenalidomide. Although sGRP78 expression was present at all stages, it increased with disease progression and was even strongly elevated in patients with drug-resistant and extramedullary disease. Pretreatment with dexamethasone as well as dual combination of PAT-SM6/lenalidomide further increased sGRP78 expression and consecutively showed synergistic anti-multiple myeloma effects with PAT-SM6 in proliferation assays. As proof of concept, a 62-year-old male with triple resistant multiple myeloma treated with PAT-SM6, bortezomib, and lenalidomide experienced partial remission of both intra- and extramedullary lesions. PAT-SM6 therapy in combination regimens showed efficacy in relapsed-refractory multiple myeloma. Clin Cancer Res; 22(17); 4341-9. ©2016 AACR. ©2016 American Association for Cancer Research.

Long-Term Response and Remission with Pixantrone in Patients with Relapsed or Refractory Aggressive Non-Hodgkin Lymphoma: Post-Hoc Analysis of the Multicenter, Open-Label, Randomized PIX301 Trial.

PubMed

Pettengell, Ruth; Coiffier, Bertrand; Egorov, Anton; Singer, Jack; Sivcheva, Lilia

2018-06-01

Pixantrone is recommended in relapsed and refractory non-Hodgkin lymphoma (NHL) or heavily pretreated NHL patients. Its conditional approval in Europe was based on results from the open-label, randomized, phase 3 PIX301 study, comparing pixantrone monotherapy with physician's choice of treatment in 140 patients with relapsed or refractory aggressive NHL. This post-hoc analysis of the PIX301 study investigated possible correlations between patient characteristics and clinical response in 17 patients (24%) treated with pixantrone who achieved a complete response (CR) or an unconfirmed complete response (CRu) at study end. These patients (10 male and 7 female) had a median age of 61 (range 41-75) years, and the most common diagnoses were diffuse large B-cell lymphoma (n = 10) and transformed indolent lymphoma (n = 4). Most had received two prior lines of therapy (n = 12). There was wide variation in the time from diagnosis to study entry (219-4777 days). Among the 17 patients who achieved a CR/CRu with pixantrone, 6 had stable or progressive disease as a response to their last regimen, 7 had a partial response, and 4 had a CR/CRu. Four patients from the pixantrone group survived without progression for more than 400 days. Prior response to previous therapies did not appear to affect long-term response to pixantrone. These observations suggest that pixantrone monotherapy in patients with multiply relapsed or refractory aggressive NHL who had received at least two prior therapies can be associated with durable responses and long-term remission, and this may be unrelated to the clinical response to the last therapy.

Bendamustine in Combination With Gemcitabine and Vinorelbine Is an Effective Regimen As Induction Chemotherapy Before Autologous Stem-Cell Transplantation for Relapsed or Refractory Hodgkin Lymphoma: Final Results of a Multicenter Phase II Study.

PubMed

Santoro, Armando; Mazza, Rita; Pulsoni, Alessandro; Re, Alessandro; Bonfichi, Maurizio; Zilioli, Vittorio Ruggero; Salvi, Flavia; Merli, Francesco; Anastasia, Antonella; Luminari, Stefano; Annechini, Giorgia; Gotti, Manuel; Peli, Annalisa; Liberati, Anna Marina; Di Renzo, Nicola; Castagna, Luca; Giordano, Laura; Carlo-Stella, Carmelo

2016-09-20

This multicenter, open-label, phase II study evaluated the combination of bendamustine, gemcitabine, and vinorelbine (BeGEV) as induction therapy before autologous stem-cell transplantation (ASCT) in patients with relapsed or refractory Hodgkin lymphoma (HL). Patients with HL who were refractory to or had relapsed after one previous chemotherapy line were eligible. The primary end point was complete response (CR) rate after four cycles of therapy. Secondary end points were: overall response rate, stem-cell mobilization activity, and toxicity. Progression-free and overall survival were also evaluated. In total, 59 patients were enrolled. After four cycles of therapy, 43 patients (73%) achieved CR, and six (10%) achieved partial response, for an overall response rate of 83%. The most common grade 3 to 4 nonhematologic toxicities included febrile neutropenia (n = 7) and infection (n = 4). Regarding hematologic toxicities, grade 3 to 4 thrombocytopenia and neutropenia were each experienced by eight patients (13.5%). CD34+ cells were successfully harvested in 55 of 57 evaluable patients, and 43 of 49 responding patients underwent ASCT. With a median follow-up of 29 months, the 2-year progression-free and overall survival rates for the total population were 62.2% and 77.6%, respectively. The same figures for patients undergoing autograft were 80.8% and 89.3%, respectively. This phase II study demonstrates that BeGEV is an effective salvage regimen able to induce CR in a high proportion of patients with relapsed or refractory HL before ASCT. These data provide a strong rationale for further development of the BeGEV regimen. © 2016 by American Society of Clinical Oncology.

Peptide receptor radionuclide therapy of treatment-refractory metastatic thyroid cancer using 90Yttrium and 177Lutetium labeled somatostatin analogs: toxicity, response and survival analysis

PubMed Central

Budiawan, Hendra; Salavati, Ali; Kulkarni, Harshad R; Baum, Richard P

2014-01-01

The overall survival rate of non-radioiodine avid differentiated (follicular, papillary, medullary) thyroid carcinoma is significantly lower than for patients with iodine-avid lesions. The purpose of this study was to evaluate toxicity and efficacy (response and survival) of peptide receptor radionuclide therapy (PRRT) in non-radioiodine-avid or radioiodine therapy refractory thyroid cancer patients. Sixteen non-radioiodine-avid and/or radioiodine therapy refractory thyroid cancer patients, including follicular thyroid carcinoma (n = 4), medullary thyroid carcinoma (n = 8), Hürthle cell thyroid carcinoma (n = 3), and mixed carcinoma (n = 1) were treated with PRRT by using 90Yttrium and/or 177Lutetium labeled somatostatin analogs. 68Ga somatostatin receptor PET/CT was used to determine the somatostatin receptor density in the residual tumor/metastatic lesions and to assess the treatment response. Hematological profiles and renal function were periodically examined after treatment. By using fractionated regimen, only mild, reversible hematological toxicity (grade 1) or nephrotoxicity (grade 1) were seen. Response assessment (using EORTC criteria) was performed in 11 patients treated with 2 or more (maximum 5) cycles of PRRT and showed disease stabilization in 4 (36.4%) patients. Two patients (18.2%) showed partial remission, in the remaining 5 patients (45.5%) disease remained progressive. Kaplan-Meier analysis resulted in a mean survival after the first PRRT of 4.2 years (95% CI, range 2.9-5.5) and median progression free survival of 25 months (inter-quartiles: 12-43). In non-radioiodine-avid/radioiodine therapy refractory thyroid cancer patients, PRRT is a promising therapeutic option with minimal toxicity, good response rate and excellent survival benefits. PMID:24380044

Gemcitabine, dexamethasone, and cisplatin (GDP) as salvage chemotherapy for patients with relapsed or refractory peripheral T cell lymphoma-not otherwise specified.

PubMed

Qi, Fei; Dong, Mei; He, Xiaohui; Li, Yexiong; Wang, Weihu; Liu, Peng; Yang, Jianliang; Gui, Lin; Zhang, Changgong; Yang, Sheng; Zhou, Shengyu; Shi, Yuankai

2017-02-01

Standard therapeutic options for patients with relapsed or refractory peripheral T cell lymphoma-not otherwise specified (PTCL-NOS) remain unclear. There are few large cohort studies specifically focused on gemcitabine-based chemotherapy for PTCL-NOS. We retrospectively reviewed patients with relapsed or refractory PTCL-NOS who received salvage GDP (gemcitabine, dexamethasone, and cisplatin) chemotherapy at the Cancer Hospital, Chinese Academy of Medical Sciences (CAMS) and Peking Union Medical College (PUMC), Beijing, China, from May 2008 to August 2014. Twenty-five patients were enrolled and analyzed. The median number of cycles of GDP chemotherapy per patient was four (range, 2-8 cycles). Overall response rate was 64.0% (16/25) with five achieved complete remission or complete remission unconfirmed. After a median follow-up of 9 months, median overall survival (OS) and progression-free survival after relapse or progression (second-PFS) were 9.3 and 5.4 months. One-year PFS rate and 1-year OS rate were 27.4% and 43.9%, respectively. Median second-PFS was significantly longer in patients sensitive to GDP than the ones resistant to the treatment (10.3 vs. 2.8 months, p < .01). In addition, the low International Prognostic Index, low Prognostic Index for T cell lymphoma, or normal level of LDH in serum was associated with favorable prognosis. Grade 3/4 adverse effect was observed in 10 of 25 patients treated with GDP including neutropenia (8/25), thrombocytopenia (5/25), and anemia (4/25). Taken together, our study suggests that GDP is an effective and optional salvage regimen for relapsed or refractory PTCL-NOS.

A review of a novel, Bruton's tyrosine kinase inhibitor, ibrutinib.

PubMed

Lee, Chung-Shien; Rattu, Mohammad A; Kim, Sara S

2016-02-01

Ibrutinib, a Bruton's kinase inhibitor, was granted an accelerated approval by the US Food and Drug Administration in November, 2013, for the treatment of relapsed or refractory mantle cell lymphoma and subsequently for the treatment of relapsed refractory chronic lymphocytic leukemia in February, 2014. In the pivotal phase 2 study of 111 patients with relapsed or refractory mantle cell lymphoma, the overall response rate in patients who received ibrutinib 560 mg daily was 68%. The median progression-free survival was 13.9 months, and the overall survival was 58% at 18 months. In a recently published phase 3 trial (RESONATE) that compared ibrutinib and ofatumumab for the treatment of relapsed and refractory chronic lymphocytic leukemia or small lymphocytic lymphoma, ibrutinib at the daily dosage of 420 mg demonstrated a significantly higher overall response rate (43% in ibrutinib vs. 4% in ofatumumab) and a significantly improved overall survival at 12 months (90% ibrutinib vs. 81% ofatumumab). Similar clinical benefits were shown regardless of del (17 p). Ibrutinib was well tolerated, and dose-limiting toxicity was not observed. Ibrutinib has shown durable remission, improved progression-free survival and overall survival, and favorable safety profile in indolent B-cell lymphoid malignancies. Ibrutinib, as a monotherapy, is an effective treatment modality as a salvage therapy for treatment of mantle cell lymphoma and chronic lymphocytic leukemia / small lymphocytic lymphoma, particularly in older patients (age ≥70 years) who are not a candidate for intensive chemotherapy and/or those with del (17 p). In patients with chronic lymphocytic leukemia and del (17 p), the current practice guideline recommends ibrutinib as an upfront treatment option. Current on-going trials will further define its role as upfront therapy and/or as a combination therapy in indolent B-cell lymphoid malignancies. © The Author(s) 2014.

Energy Deposition and Condition of the Metal Core in Exploding Wire Experiments

NASA Astrophysics Data System (ADS)

Sarkisov, G. S.; Rosenthal, S. E.; Struve, K. W.; McDaniel, D. H.; Waisman, E. M.; Sasorov, P. V.

2002-11-01

Measurements of the Joule energy deposition into exploding wire and its relation with condition of the expanding wire core are presented. Wires of nine different metals with diameters of 10-30 microns, have been exploded by fast 150A/ns and slow 20A/ns pulses, in vacuum and in air. It has been shown by interferometry and light emission that expanding wire core has different conditions. The substances with small atomization enthalpy (Ag, Al, Cu, Au) demonstrate full vaporization of the wire core. The refractory metals (Ti, Pt, Mo, W) demonstrates that core consists from vapor and small and hot microparticles. In this case we observe "firework effect" when large radiation from the wire exceed the energy deposition time in a three order of magnitude. For non-refractory metals radiation dropping fast in 100 ns time scale due to effective adiabatic cooling. It is possible if main part of the metal core was vaporized. The interferometrical investigation of the refraction coefficient of expanding metal core is proof this conclusion. It has been shown that energy deposition before surface breakdown dependent strongly from current rate, surface coatings, environment, wire diameter and radial electric field. The regime of wire explosion in vacuum without shunting plasma shell has been realized for fast exploding mode. In this case we observe anomaly high energy deposition in to the wire core exceeding regular value in almost 20 times. The experimental results for Al wire have been compared with ALEGRA 2D MHD simulations. *Sandia is a multi-program laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under Contract DE-AC04-94AL8500.

ZIRCONIUM-TITANIUM-BERYLLIUM BRAZING ALLOY

DOEpatents

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)

Molecular-Orbital Models for the Catayltic Activity and Selectivity of Coordinatively Unsaturated Platinum Surfaces and Complexes.

DTIC Science & Technology

1980-12-31

surfaces. Reactions involving the Pt(O)- triphenylphosphine complexes Pt(PPh 3)n, where n = 2, 3, 4, have been shown to have precise analogues on Pt...12], the triphenylphosphine (PPh 3 ) group is modeled by the simpler but chemically similar phosphine (PH3) group. The appropriate Pt-P bond distances...typically refractory oxides ) are of sufficient magnitude as to suggest significant chemical and electronic modifications of the metal at the metal-support

Chemical Processing Manual

NASA Technical Reports Server (NTRS)

Beyerle, F. J.

1972-01-01

Chemical processes presented in this document include cleaning, pickling, surface finishes, chemical milling, plating, dry film lubricants, and polishing. All types of chemical processes applicable to aluminum, for example, are to be found in the aluminum alloy section. There is a separate section for each category of metallic alloy plus a section for non-metals, such as plastics. The refractories, super-alloys and titanium, are prime candidates for the space shuttle, therefore, the chemical processes applicable to these alloys are contained in individual sections of this manual.

Doxorubicin-Loaded 70–150 μm Microspheres for Liver-Dominant Metastatic Breast Cancer: Results and Outcomes of a Pilot Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, Yen-Ting, E-mail: ymerically@gmail.com; Médioni, Jacques, E-mail: jacques.medioni@aphp.fr; Amouyal, Grégory, E-mail: gregory.amouyal@aphp.fr

PurposePatients with breast cancer liver metastasis have a poor prognosis. Local therapy for liver metastasis increases survival. The purpose of this pilot prospective study was to evaluate the efficacy and safety of doxorubicin drug-eluting beads chemoembolization for liver-dominant breast cancer metastasis (LdBM) refractory to chemotherapy.Materials and MethodsAll patients with LdBM refractory to of two or more lines of systemic chemotherapy were screened. Two chemoembolizations at 1-month intervals were scheduled for each patient. Tumor responses were evaluated by MRI every 3 months until progression or death. Adverse events were recorded according to the Common Terminology Criteria for Adverse Events (CTCAE version 4.02)more » 1 month after each chemoembolization. All patients were free from systemic treatment until progression. Patients with hormone-positive receptors and/or HER-positive disease status continued their targeted therapy.ResultsOut of 23 patients enrolled (mean age: 57.5 ± 11.5 years), 17 completed two chemoembolizations and six underwent only one because of severe adverse events. At 3-month follow-up, the disease control rate was 83 %. The median progression-free survival from the first chemoembolization was 8 months, and the median overall survival was 17 months. Nineteen patients remained free from any systemic chemotherapy for a mean of 209 ± 92 days until progression. Eight grade 3 (asthenia n = 3, anemia n = 2, thrombocythemia n = 2, liver toxicity n = 1) (Rev 1 Comment 1) occurred after the first procedure. No patient died directly due to the procedure.ConclusionWhile chemoembolization with doxorubicin eluding beads for refractory LdBM leads to an 83 % disease control rate, it also causes severe side effects that need to be adequately managed.« less

Predictors of response, progression-free survival, and overall survival using NANT Response Criteria (v1.0) in relapsed and refractory high-risk neuroblastoma.

PubMed

Villablanca, Judith G; Ji, Lingyun; Shapira-Lewinson, Adi; Marachelian, Araz; Shimada, Hiroyuki; Hawkins, Randall A; Pampaloni, Miguel; Lai, Hollie; Goodarzian, Fariba; Sposto, Richard; Park, Julie R; Matthay, Katherine K

2018-05-01

The New Approaches to Neuroblastoma Therapy Response Criteria (NANTRC) were developed to optimize response assessment in patients with recurrent/refractory neuroblastoma. Response predictors and associations of the NANTRC version 1.0 (NANTRCv1.0) and prognostic factors with outcome were analyzed. A retrospective analysis was performed of patients with recurrent/refractory neuroblastoma enrolled from 2000 to 2009 on 13 NANT Phase 1/2 trials. NANTRC overall response integrated CT/MRI (Response Evaluation Criteria in Solid Tumors [RECIST]), metaiodobenzylguanidine (MIBG; Curie scoring), and percent bone marrow (BM) tumor (morphology). Fourteen (6.9%) complete response (CR) and 14 (6.9%) partial response (PR) occurred among 203 patients evaluable for response. Five-year progression-free survival (PFS) was 16 ± 3%; overall survival (OS) was 27 ± 3%. Disease sites at enrollment included MIBG-avid lesions (100% MIBG trials; 84% non-MIBG trials), measurable CT/MRI lesions (48%), and BM (49%). By multivariable analysis, Curie score of 0 (P < 0.001), lower Curie score (P = 0.003), no measurable CT/MRI lesions (P = 0.044), and treatment on peripheral blood stem cell (PBSC) supported trials (P = 0.005) were associated with achieving CR/PR. Overall response of stable disease (SD) or better was associated with better OS (P < 0.001). In multivariable analysis, MYCN amplification (P = 0.037) was associated with worse PFS; measurable CT/MRI lesions (P = 0.041) were associated with worse OS; prior progressive disease (PD; P < 0.001/P < 0.001), Curie score ≥ 1 (P < 0.001; P = 0.001), higher Curie score (P = 0.048/0.037), and treatment on non-PBSC trials (P = < 0.001/0.003) were associated with worse PFS and OS. NANTRCv1.0 response of at least SD is associated with better OS in patients with recurrent/refractory neuroblastoma. Patient and tumor characteristics may predict response and outcome. Identifying these variables can optimize Phase 1/2 trial design to select novel agents for further testing. © 2018 Wiley Periodicals, Inc.

The management of metastatic radioiodine-refractory differentiated thyroid cancer requires an integrated approach including both directed and systemic therapies.

PubMed

Cooray, Shamil D; Topliss, Duncan J

2017-01-01

A 58-year-old man with metastatic radioiodine-refractory differentiated thyroid cancer (DTC) presented with left thigh and right flank numbness. He had known progressive and widespread bony metastases, for which he received palliative radiotherapy, and multiple bilateral asymptomatic pulmonary metastases. CT scan and MRI of the spine revealed metastases at right T10-L1 vertebrae with extension into the central canal and epidural disease at T10 and T11 causing cord displacement and canal stenosis but retention of spinal cord signal. Spinal surgery was followed by palliative radiotherapy resulting in symptom resolution. Two months later, sorafenib received approval for use in Australia and was commenced and up-titrated with symptomatic management of mild adverse effects. Follow-up CT scan three months after commencement of sorafenib revealed regression of pulmonary metastases but no evident change in most bone metastases except for an advancing lesion eroding into the right acetabulum. The patient underwent a right total hip replacement, intra-lesional curettage and cementing. After six months of sorafenib therapy, CT scanning showed enlarging liver lesions with marked elevation of serum thyroglobulin. Lenvatinib was commenced and sorafenib was ceased. He now has stable disease with a falling thyroglobulin more than 5 years after metastatic radioiodine-refractory DTC was diagnosed. In DTC, 5% of distant metastases become radioiodine-refractory, resulting in a median overall survival of 2.5-3.5 years. Tyrosine kinase inhibitor (TKI) therapy has recently been demonstrated to increase progression-free survival in these patients but poses some unique management issues and is best used as part of an integrated approach with directed therapy. Directed therapies may have greater potential to control localised disease and related symptoms when compared to systemic therapies.Consider TKI therapy in progressive disease where benefits outweigh risks.Active surveillance and timely intervention are required for TKI-related adverse effects.There is a need for further research on the clinical application of TKI therapy in advanced DTC, including comparative efficacy, sequencing and identifying responders.

Natural variations in the rhenium isotopic composition of meteorites

NASA Astrophysics Data System (ADS)

Liu, R.; Hu, L.; Humayun, M.

2017-03-01

Rhenium is an important element with which to test hypotheses of isotope variation. Historically, it has been difficult to precisely correct the instrumental mass bias in thermal ionization mass spectrometry. We used W as an internal standard to correct mass bias on the MC-ICP-MS, and obtained the first precise δ187Re values ( ±0.02‰, 2SE) for iron meteorites and chondritic metal. Relative to metal from H chondrites, IVB irons are systematically higher in δ187Re by 0.14 ‰. δ187Re for other irons are similar to H chondritic metal, although some individual samples show significant isotope fractionation. Since 185Re has a high neutron capture cross section, the effect of galactic cosmic-ray (GCR) irradiation on δ187Re was examined using correlations with Pt isotopes. The pre-GCR irradiation δ187Re for IVB irons is lower, but the difference in δ187Re between IVB irons and other meteoritic metal remains. Nuclear volume-dependent fractionation for Re is about the right magnitude near the melting point of iron, but because of the refractory and compatible character of Re, a compelling explanation in terms of mass-dependent fractionation is elusive. The magnitude of a nucleosynthetic s-process deficit for Re estimated from Mo and Ru isotopes is essentially unresolvable. Since thermal processing reduced nucleosynthetic effects in Pd, it is conceivable that Re isotopic variations larger than those in Mo and Ru may be present in IVBs since Re is more refractory than Mo and Ru. Thus, the Re isotopic difference between IVBs and other irons or chondritic metal remains unexplained.

Process for HIP canning of composites

NASA Technical Reports Server (NTRS)

Juhas, John J. (Inventor)

1990-01-01

A single step is relied on in the canning process for hot isostatic pressing (HIP) metallurgy composites. The composites are made from arc sprayed and plasma sprayed monotape. The HIP can is of compatible refractory metal and is sealed at high vacuum and temperature. This eliminates outgassing during hot isostatic pressing.

The Use of an Air-Natural Gas Flame in Atomic Absorption.

ERIC Educational Resources Information Center

Melucci, Robert C.

1983-01-01

Points out that excellent results are obtained using an air-natural gas flame in atomic absorption experiments rather than using an air-acetylene flame. Good results are obtained for alkali metals, copper, cadmium, and zinc but not for the alkaline earths since they form refractory oxides. (Author/JN)

Refractory porcelain enamel passive-thermal-control coating for high-temperature superalloys

NASA Technical Reports Server (NTRS)

Levin, H.; Auker, B. H.; Gardos, M. N.

1973-01-01

Study was conducted to match thermal expansion coefficients thereby preventing enamels from cracking. Report discusses various enamel coatings that are applied to two different high-temperature superalloys. Study may be of interest to manufacturers of chemical equipment, furnaces, and metal components intended for high-temperature applications.

Reduced-Intensity Allografting as First Transplantation Approach in Relapsed/Refractory Grades One and Two Follicular Lymphoma Provides Improved Outcomes in Long-Term Survivors.

PubMed

Klyuchnikov, Evgeny; Bacher, Ulrike; Kröger, Nicolaus M; Hari, Parameswaran N; Ahn, Kwang Woo; Carreras, Jeanette; Bachanova, Veronika; Bashey, Asad; Cohen, Jonathon B; D'Souza, Anita; Freytes, César O; Gale, Robert Peter; Ganguly, Siddhartha; Hertzberg, Mark S; Holmberg, Leona A; Kharfan-Dabaja, Mohamed A; Klein, Andreas; Ku, Grace H; Laport, Ginna G; Lazarus, Hillard M; Miller, Alan M; Mussetti, Alberto; Olsson, Richard F; Slavin, Shimon; Usmani, Saad Z; Vij, Ravi; Wood, William A; Maloney, David G; Sureda, Anna M; Smith, Sonali M; Hamadani, Mehdi

2015-12-01

This study was conducted to compare long-term outcomes in patients with refractory/relapsed grades 1 and 2 follicular lymphoma (FL) after allogeneic (allo) versus autologous (auto) hematopoietic cell transplantation (HCT) in the rituximab era. Adult patients with relapsed/refractory grades 1 and 2 FL undergoing first reduced-intensity allo-HCT or first autograft during 2000 to 2012 were evaluated. A total of 518 rituximab-treated patients were included. Allo-HCT patients were younger and more heavily pretreated, and more patients had advanced stage and chemoresistant disease. The 5-year adjusted probabilities, comparing auto-HCT versus allo-HCT groups for nonrelapse mortality (NRM) were 5% versus 26% (P < .0001); relapse/progression: 54% versus 20% (P < .0001); progression-free survival (PFS): 41% versus 58% (P < .001), and overall survival (OS): 74% versus 66% (P = .05). Auto-HCT was associated with a higher risk of relapse/progression beyond 5 months after HCT (relative risk [RR], 4.4; P < .0001) and worse PFS (RR, 2.9; P < .0001) beyond 11 months after HCT. In the first 24 months after HCT, auto-HCT was associated with improved OS (RR, .41; P < .0001), but beyond 24 months, it was associated with inferior OS (RR, 2.2; P = .006). A landmark analysis of patients alive and progression-free at 2 years after HCT confirmed these observations, showing no difference in further NRM between both groups, but there was significantly higher risk of relapse/progression (RR, 7.3; P < .0001) and inferior PFS (RR, 3.2; P < .0001) and OS (RR, 2.1; P = .04) after auto-HCT. The 10-year cumulative incidences of second hematological malignancies after allo-HCT and auto-HCT were 0% and 7%, respectively. Auto-HCT and reduced-intensity-conditioned allo-HCT as first transplantation approach can provide durable disease control in grades 1 and 2 FL patients. Continued disease relapse risk after auto-HCT translates into improved PFS and OS after allo-HCT in long-term survivors. Copyright © 2015 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

Ulcerative proctitis: an update on the pharmacotherapy and management.

PubMed

Gecse, Krisztina B; Lakatos, Peter L

2014-08-01

Ulcerative colitis (UC) presents as proctitis in approximately a quarter of the patients. It may progress into left-sided or extensive colitis in up to 50% of cases upon long-term follow-up. Currently available data on ulcerative proctitis are summarized and critically reviewed. Extensive literature search (MEDLINE) was performed to identify relevant articles up to March 2014. The short-term goal of the treatment in UC is to induce remission, whereas long-term goals are to maintain remission and prevent disease progression. Topically administered 5-aminosalicylates (5-ASA) and corticosteroids are effective in the treatment of proctitis, although they seem to be underused in everyday practice. Locally administered 5-ASA preparations are more effective than oral compounds. The combination of topical and oral 5-ASA and steroids should be considered for escalation of treatment. Refractory patients should be re-evaluated to exclude for compliance failures, infections or proximal disease extent. True refractory or steroid-dependent patients may require immunomodulators or biological therapy. Alternative medicine can be used complementarily, while experimental approaches are reserved for patients failing conventional medication. Proctocolectomy may be the last resort of treatment. Upon long-term, 5-ASA maintenance treatment is indicated in all UC cases to prevent relapse and disease progression.

The natural history of skin-limited Langerhans cell histiocytosis: a single-institution experience.

PubMed

Ehrhardt, Matthew J; Humphrey, Stephen R; Kelly, Michael E; Chiu, Yvonne E; Galbraith, Sheila S

2014-11-01

Prior reports of Langerhans cell histiocytosis (LCH) suggest that isolated skin involvement is rare and often progresses to systemic disease. More rapid access to pediatric subspecialty care has likely led to more frequent representation of this condition. The purpose of this study is to characterize the natural history of skin-limited LCH in an era of increased access to pediatric subspecialty care. A retrospective chart review was performed on all patients newly diagnosed with LCH between 2001 and 2012 at the Children's Hospital of Wisconsin. Extensive review of laboratory, physical examination, and imaging reports was performed and data collected for patients with biopsy-proven skin LCH. Sixteen individuals with skin-limited LCH were identified. The median age at onset of skin eruption was birth (range, birth to 6 mo), and median duration of follow-up was 19.5 months (range, 2 wk to 10 y) from diagnosis. One patient (6%) developed pituitary disease and 1 patient (6%) had refractory skin involvement. All others experienced complete resolution. For patients without progressive or refractory disease, resolution of skin findings occurred within 7 months from onset. Progression of skin-limited to multisystem LCH likely may be less frequent than previously described.

Combination therapy of ethinylestradiol and somatostatin analogue reintroduces objective clinical responses and decreases chromogranin a in patients with androgen ablation refractory prostate cancer.

PubMed

Di Silverio, Franco; Sciarra, Alessandro

2003-11-01

We evaluated whether a combination therapy of ethinylestradiol and somatostatin analogue can reintroduce objective clinical responses in patients with metastatic androgen ablation refractory prostate cancer (PC). Ten patients with stage D3 disease and bone metastases who had progression despite initial responses to combined androgen blockade and in whom antiandrogen withdrawal subsequently failed discontinued combined androgen blockade and received 1 mg ethinylestradiol orally daily and 73.9 mg lanreotide acetate intramuscularly every 4 weeks. Serum prostate specific antigen (PSA), chromogranin A (CgA), Eastern Cooperative Oncology Group performance status and bone pain scores were assessed at regular intervals. Median followup was 18 months (range 10 to 24). Nine of the 10 cases (90%, 95% CI 55.5 to 99.8) had an objective clinical response, defined as a greater than 50% PSA decrease (median 87.1%, range 50.2% to 94.4%). PSA normalization (less than 4 ng/ml) was achieved in 3 cases. All patients reported significant and durable improvement in bone pain (median duration 17.5 months) and performance status (median duration 18 months) without major treatment related side effects. Two patients with disease progression died secondary to PC at 16 and 10 months, respectively. All other patients were without progression. We observed a statistically significant decrease in serum CgA during administration and at the response to therapy (median 38.4%, range 28.6% to 64.9%, (p <0.0001). Interestingly CgA was not increased at relapse. This combination therapy seems to reintroduce an objective clinical response and symptomatic improvement in androgen ablation refractory PC cases.

Advances in chemical and physical properties of electric arc furnace carbon steel slag by hot stage processing and mineral mixing.

PubMed

Liapis, Ioannis; Papayianni, Ioanna

2015-01-01

Slags are recognised as a highly efficient, cost effective tool in the metal processing industry, by minimising heat losses, reducing metal oxidation through contact with air, removing metal impurities and protecting refractories and graphite electrodes. When compared to natural aggregates for use in the construction industry, slags have higher specific weight that acts as an economic deterrent. A method of altering the specific weight of EAFC slag by hot stage processing and mineral mixing, during steel production is presented in this article. The method has minimal interference with the production process of steel, even by limited additions of appropriate minerals at high temperatures. Five minerals are examined, namely perlite, ladle furnace slag, bauxite, diatomite and olivine. Measurements of specific weight are accompanied by X-ray diffraction (XRD) and fluorescence (XRF) analysis and scanning electron microscopy spectral images. It is also shown how altering the chemical composition is expected to affect the furnace refractory lining. Additionally, the process has been repeated for the most suitable mix in gas furnace and physical properties (FI, SI, LA, PSV, AAV, volume stability) examined. Alteration of the specific weight can result in tailoring slag properties for specific applications in the construction sector. Copyright © 2014 Elsevier B.V. All rights reserved.

Low-dose decitabine-based chemoimmunotherapy for patients with refractory advanced solid tumors: a phase I/II report.

PubMed

Fan, Hui; Lu, Xuechun; Wang, Xiaohui; Liu, Yang; Guo, Bo; Zhang, Yan; Zhang, Wenying; Nie, Jing; Feng, Kaichao; Chen, Meixia; Zhang, Yajing; Wang, Yao; Shi, Fengxia; Fu, Xiaobing; Zhu, Hongli; Han, Weidong

2014-01-01

Aberrant DNA methylation is one of the main drivers of tumor initiation and progression. The reversibility of methylation modulation makes it an attractive target for novel anticancer therapies. Clinical studies have demonstrated that high-dose decitabine, a hypomethylating agent, results in some clinical benefits in patients with refractory advanced tumors; however, they are extremely toxic. Low doses of decitabine minimize toxicity while potentially improving the targeted effects of DNA hypomethylation. Based on these mechanisms, low-dose decitabine combined with chemoimmunotherapy may be a new treatment option for patients with refractory advanced tumors. We proposed the regimen of low-dose decitabine-based chemoimmunotherapy for patients with refractory advanced solid tumors. A favorable adverse event profile was observed in our trial that was highlighted by the finding that most of these adverse events were grades 1-2. Besides, the activity of our cohort was optimistic and the clinical benefit rate was up to 60%, and the median PFS was prolonged compared with PFS to previous treatment. We also identified a significant correlation between the PFS to previous treatment and clinical response. The low-dose DAC decitabine-based chemoimmunotherapy might be a promising protocol for improving the specificity and efficiency of patients with refractory advanced solid tumors. This trial is registered in the ClinicalTrials.gov database (identifier NCT01799083).

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

NASA Astrophysics Data System (ADS)

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 <49% up to 83%) and silver (e.g., from <18% up to 90%) to subsequent cyanide 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.

Ir-based refractory superalloys by pulse electric current sintering (PECS) process (II prealloyed powder)

NASA Astrophysics Data System (ADS)

Huang, C.; Yamabe-Mitarai, Y.; Harada, H.

2002-02-01

Five prealloyed powder samples prepared from binary Ir-based refractory superalloys were sintered at 1800 °C for 4 h by Pulse Electric Current Sintering (PECS). No metal loss was observed during sintering. The relative densities of the sintered specimens all exceeded 90% T.D. The best one was Ir-13% Hf with the density of 97.82% T.D. Phases detected in sintered samples were in accordance with the phase diagram as expected. Fractured surfaces were observed in two samples (Ir-13% Hf and Ir-15% Zr). Some improvements obtained by using prealloyed powders instead of elemental powders, which were investigated in the previous studies, were presented.

CRUCIBLE LINING METHOD

DOEpatents

Bone, W.H.; Schmidt, W.W.

1958-11-01

A method is presented for forming refractory liners in cylindrical reaction vessels used for the reductlon of uranium tetrafluoride to metallic uranium. A preliminary form, having positioning lugs attached thereto, is inserted into the reaction vessel and the refractory powder, usually CaO, is put in the annular space between the form and the inner wall of the reaction vessel. A jolting table is used to compact this charge of liner material ln place, and after thls has been done, the preliminary form is removed and the flnal form or plug is lnserted without disturbing the partially completed lining. The remainder of the lining charge is then introduced and compacted by jolting, after which the form is removed.

Silicon-nitride and metal composite

DOEpatents

Landingham, R.L.; Huffsmith, S.A.

A composite and a method for bonding the composite are described. The composite includes a ceramic portion of silicon nitride, a refractory metal portion and a layer of MoSi/sub 2/ indirectly bonding the composite together. The method includes contacting the layer of MoSi/sub 2/ with a surface of the silicon nitride and with a surface of the metal; heating the layer to a temperature below 1400/sup 0/C; and, simultaneously, compressing the layer such that the contacting is with a pressure of at least 30 MPa. This composite overcomes useful life problems in the fabrication of parts for a helical expander for use in power generation.

Silicon-nitride and metal composite

DOEpatents

Landingham, Richard L.; Huffsmith, Sarah A.

1981-01-01

A composite and a method for bonding the composite. The composite includes a ceramic portion of silicon nitride, a refractory metal portion and a layer of MoSi.sub.2 indirectly bonding the composite together. The method includes contacting the layer of MoSi.sub.2 with a surface of the silicon nitride and with a surface of the metal; heating the layer to a temperature below 1400.degree. C.; and, simultaneously with the heating, compressing the layer such that the contacting is with a pressure of at least 30 MPa. This composite overcomes useful life problems in the fabrication of parts for a helical expander for use in power generation.

Better Ohmic Contacts For InP Semiconductor Devices

NASA Technical Reports Server (NTRS)

Weizer, Victor G.; Fatemi, Navid S.

1995-01-01

Four design modifications enable fabrication of improved ohmic contacts on InP-based semiconductor devices. First modification consists of insertion of layer of gold phosphide between n-doped InP and metal or other overlayer of contact material. Second, includes first modification plus use of particular metal overlayer to achieve very low contact resistivities. Third, also involves deposition of Au(2)P(3) interlayer; in addition, refractory metal (W or Ta) deposited to form contact overlayer. In fourth, contact layer of Auln alloy deposited directly on InP. Improved contacts exhibit low electrical resistances and fabricated without exposing devices to destructive predeposition or postdeposition treatments.

A review of refractory materials for vapor-anode AMTEC cells

NASA Astrophysics Data System (ADS)

King, Jeffrey C.; El-Genk, M. S.

2000-01-01

Recently, refractory alloys have been considered as structural materials for vapor-anode Alkali Metal Thermal-to-Electric Conversion (AMTEC) cells, for extended (7-15 years) space missions. This paper reviewed the existing database for refractory metals and alloys of potential use as structural materials for vapor-anode sodium AMTEC cells. In addition to requiring that the vapor pressure of the material be below 10-9 torr (133 nPa) at a typical hot side temperature of 1200 K, other screening considerations were: (a) low thermal conductivity, low thermal radiation emissivity, and low linear thermal expansion coefficient; (b) low ductile-to-brittle transition temperature, high yield and rupture strengths and high strength-to-density ratio; and (c) good compatibility with the sodium AMTEC operating environment, including high corrosion resistance to sodium in both the liquid and vapor phases. Nb-1Zr (niobium-1% zirconium) alloy is recommended for the hot end structures of the cell. The niobium alloy C-103, which contains the oxygen gettering elements zirconium and hafnium as well as titanium, is recommended for the colder cell structure. This alloy is stronger and less thermally conductive than Nb-1Zr, and its use in the cell wall reduces parasitic heat losses by conduction to the condenser. The molybdenum alloy Mo-44.5Re (molybdenum-44.5% rhenium) is also recommended as a possible alternative for both structures if known problems with oxygen pick up and embrittlement of the niobium alloys proves to be intractable. .

Second-Line Intraperitoneal Chemotherapy for Recurrent Epithelial Ovarian, Tubal and Peritoneal Cancer: A Propensity Score-Matching Study.

PubMed

Lu, Chien-Hsing; Chang, Yen-Hou; Lee, Wai-Hou; Chang, Yi; Peng, Chia-Wen; Chuang, Chi-Mu

2016-01-01

The superiority of frontline intraperitoneal (IP) over intravenous (IV) chemotherapy is well established in the treatment of epithelial ovarian cancer. However, the role of IP chemotherapy in the second-line setting has rarely been investigated. Consecutive patients diagnosed with recurrent epithelial, tubal and peritoneal cancers between January 2000 and December 2012 were recruited using a propensity score-matching technique to adjust relevant risk factors. In total, 310 patients were included in the final analysis (94 for platinum-refractory/resistant disease and 216 for platinum-sensitive disease). IP chemotherapy demonstrated significantly longer median progression-free survival than IV chemotherapy (4.9 vs. 2.4 months, p < 0.001, for platinum-refractory/resistant disease, and 9.8 vs. 6.9 months, p < 0.001, for platinum-sensitive disease). Second-line IP chemotherapy confers longer progression-free survival than IV chemotherapy. Large-scale clinical trials should be conducted to validate the true efficacy. © 2016 S. Karger AG, Basel.

Biliary metal stents for proximal esophageal or hypopharyngeal strictures.

PubMed

Bechtler, Matthias; Wagner, Florian; Fuchs, Erik-Sebastian; Jakobs, Ralf

2015-11-01

Endoscopic dilation is the standard of care for stenoses of the cervical esophagus, but refractory strictures require some form of stenting. Most endoscopists avoid the placement of metal stents near the upper esophageal sphincter as they can cause major problems like severe cervical pain and globus sensation. We report our results with the use of biliary SEMS in the upper esophagus, which have a smaller diameter than regular esophageal stents and therefore exert less expansive force. We retrospectively reviewed all patients in our center between July 2011 and June 2014 who received a biliary metal stent because of a refractory stricture in the cervical esophagus. We implanted biliary SEMS (Wallflex, Boston Scientific) with a diameter of 1 cm and length of 6-8 cm. Technical and clinical success, adverse events and duration of stenting were evaluated. Ten patients were treated with biliary SEMS in the upper esophagus. Strictures were located between 10 and 19 cm from incisor teeth. Stent placement was successful in all (10/10) patients. One stent had to be extracted because of pain and globus sensation. Apart from that stent tolerability was good. All remaining patients (9/9) reported improvement of dysphagia with a decrease in mean dysphagia score from 3.2 to 1.78. Mean duration of stenting was 68 days. Because of a high clinical success rate and good tolerability, biliary metal stents are a reasonable alternative for difficult strictures in the cervical esophagus, especially in the palliative setting.

Role of metallic stents in benign esophageal stricture

NASA Astrophysics Data System (ADS)

Shim, Chan Sup

2012-10-01

Simple esophageal strictures, which are focal, straight, and large in diameter, usually require 1 - 3 dilation sessions to relieve symptoms. However, complex strictures, which are long, tortuous, or associated with a severely compromised luminal diameter, are usually more difficult to treat with conventional bougie or balloon dilation techniques, and often have high recurrence rates. Although the permanent placement of self-expandable metal stents (SEMS) has been used to manage refractory benign esophageal strictures, this procedure is associated with additional problems, such as stricture from tissue hyperplasia, stent migration, and fistula formation. Thus, several new types of stents have been developed, including temporary SEMS, self-expandable plastic stents (SEPS), and biodegradable stents. The use of these new products has produced varied results. Temporary SEMS that have been used to relieve benign esophageal conditions have caused granulation tissue at both ends of the stent because of contact between the mucosa and the exposed metal components of the stent, thus hindering stent removal. We examined the tissue response to two new types of SEMS, a flange-type and a straighttype, each coated with a silicone membrane on the outside of the metal mesh. These two SEMS were evaluated individually and compared with a conventional control stent in animal experiments. Although the newly designed stents resulted in reduced tissue hyperplasia, and were thus more easily separated from the esophageal tissue, some degree of tissue hyperplasia did occur. We suggest that newly designed DES (drug-eluting stents) may provide an alternative tool to manage refractory benign esophageal stricture.

Venetoclax for chronic lymphocytic leukaemia progressing after ibrutinib: an interim analysis of a multicentre, open-label, phase 2 trial.

PubMed

Jones, Jeffrey A; Mato, Anthony R; Wierda, William G; Davids, Matthew S; Choi, Michael; Cheson, Bruce D; Furman, Richard R; Lamanna, Nicole; Barr, Paul M; Zhou, Lang; Chyla, Brenda; Salem, Ahmed Hamed; Verdugo, Maria; Humerickhouse, Rod A; Potluri, Jalaja; Coutre, Steven; Woyach, Jennifer; Byrd, John C

2018-01-01

Therapy targeting Bruton's tyrosine kinase (BTK) with ibrutinib has transformed the treatment of chronic lymphocytic leukaemia. However, patients who are refractory to or relapse after ibrutinib therapy have poor outcomes. Venetoclax is a selective, orally bioavailable inhibitor of BCL-2 active in previously treated patients with relapsed or refractory chronic lymphocytic leukaemia. In this study, we assessed the activity and safety of venetoclax in patients with chronic lymphocytic leukaemia who are refractory to or relapse during or after ibrutinib therapy. In this interim analysis of a multicentre, open-label, non-randomised, phase 2 trial, we enrolled patients aged 18 years or older with a documented diagnosis of chronic lymphocytic leukaemia according to the 2008 International Workshop on Chronic Lymphocytic Leukemia (IWCLL) criteria and an Eastern Cooperative Oncology Group performance score of 2 or lower. All patients had relapsed or refractory disease after previous treatment with a BCR signalling pathway inhibitor. All patients were screened for Richter's transformation and cases confirmed by biopsy were excluded. Eligible patients received oral venetoclax, starting at 20 mg per day with stepwise dose ramp-up over 5 weeks to 400 mg per day. Patients with rapidly progressing disease received an accelerated dosing schedule (to 400 mg per day by week 3). The primary endpoint was overall response, defined as the proportion of patients with an overall response per investigator's assessment according to IWCLL criteria. All patients who received at least one dose of venetoclax were included in the activity and safety analyses. This study is ongoing; data for this interim analysis were collected per regulatory agencies' request as of June 30, 2017. This trial is registered with ClinicalTrials.gov, number NCT02141282. Between September, 2014, and November, 2016, 127 previously treated patients with relapsed or refractory chronic lymphocytic leukaemia were enrolled from 15 sites across the USA. 91 patients had received ibrutinib as the last BCR inhibitor therapy before enrolment, 43 of whom were enrolled in the main cohort and 48 in the expansion cohort recruited later after a protocol amendment. At the time of analysis, the median follow-up was 14 months (IQR 8-18) for all 91 patients, 19 months (9-27) for the main cohort, and 12 months (8-15) for the expansion cohort. 59 (65%, 95% CI 53-74) of 91 patients had an overall response, including 30 (70%, 54-83) of 43 patients in the main cohort and 29 (60%, 43-72) of 48 patients in the expansion cohort. The most common treatment-emergent grade 3 or 4 adverse events were neutropenia (46 [51%] of 91 patients), thrombocytopenia (26 [29%]), anaemia (26 [29%]), decreased white blood cell count (17 [19%]), and decreased lymphocyte count (14 [15%]). 17 (19%) of 91 patients died, including seven because of disease progression. No treatment-related deaths occurred. The results of this interim analysis show that venetoclax has durable clinical activity and favourable tolerability in patients with relapsed or refractory chronic lymphocytic leukaemia whose disease progressed during or after discontinutation of ibrutinib therapy. The durability of response to venetoclax will be assessed in the final analysis in 2019. AbbVie, Genentech. Copyright © 2018 Elsevier Ltd. All rights reserved.

A refractory inclusion returned by Stardust from comet 81P/Wild 2

NASA Astrophysics Data System (ADS)

Simon, S. B.; Joswiak, D. J.; Ishii, H. A.; Bradley, J. P.; Chi, M.; Grossman, L.; AlÉOn, J.; Brownlee, D. E.; Fallon, S.; Hutcheon, I. D.; Matrajt, G.; McKeegan, K. D.

2008-11-01

Among the samples returned from comet 81P/Wild 2 by the Stardust spacecraft is a suite of particles from one impact track (Track 25) that are Ca-, Al-rich and FeO-free. We studied three particles from this track that range in size from 5.3 × 3.2 μ to 15 × 10 μ. Scanning and transmission electron microscopy show that they consist of very fine-grained (typically from ˜0.5 to ˜2 μ) Al-rich, Ti-bearing and Ti-free clinopyroxene, Mg-Al spinel and anorthite, with trace amounts of fine perovskite, FeNi metal and osbornite (TiN) grains. In addition to these phases, the terminal particle, named "Inti", also contains melilite. All of these phases, with the exception of osbornite, are common in refractory inclusions and are predicted to condense at high temperature from a gas of solar composition. Osbornite, though very rare, has also been found in meteoritic refractory inclusions, and could have formed in a region of the nebula where carbon became enriched relative to oxygen compared to solar composition. Compositions of Ti-pyroxene in Inti are similar, but not identical, to those of fassaite from Allende inclusions. Electron energy loss spectroscopy shows that Ti-rich pyroxene in Inti has Ti3+/Ti4+within the range of typical meteoritic fassaite, consistent with formation under reducing conditions comparable to those of a system of solar composition. Inti is 16O-rich, with δ18O?δ17O?-40%0, like unaltered phases in refractory inclusions and refractory IDPs. With grain sizes, mineralogy, mineral chemistry, and an oxygen isotopic composition like those of refractory inclusions, we conclude that Inti is a refractory inclusion that formed in the inner solar nebula. Identification of a particle that formed in the inner solar system among the comet samples demonstrates that there was transport of materials from the inner to the outer nebula, probably either in a bipolar outflow or by turbulence.

DEEP DESULFURIZATION OF DIESEL FUELS BY A NOVEL INTEGRATED APPROACH

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xiaoliang Ma; Uday Turaga; Shingo Watanabe

2004-05-01

The overall objective of this project is to explore a new desulfurization system concept, which consists of efficient separation of the refractory sulfur compounds from diesel fuel by selective adsorption, and effective hydrodesulfurization of the concentrated fraction of the refractory sulfur compounds in diesel fuels. Our approaches focused on (1) selecting and developing new adsorbents for selective adsorption of sulfur or sulfur compounds in commercial diesel fuel; (2) conducting the adsorption desulfurization of model fuels and real diesel fuels by the selective-adsorption-for-removing-sulfur (PSUSARS) process over various developed adsorbents, and examining the adsorptive desulfurization performance of various adsorbents; (3) developing andmore » evaluating the regeneration methods for various spent adsorbent; (4) developing new catalysts for hydrodesulfurization of the refractory sulfur existing in the commercial diesel fuel; (5) on the basis of the fundamental understanding of the adsorptive performance and regeneration natures of the adsorbents, further confirming and improving the conceptual design of the novel PSU-SARS process for deep desulfurization of diesel fuel Three types of adsorbents, the metal-chloride-based adsorbents, the activated nickel-based adsorbents and the metal-sulfide-based adsorbents, have been developed for selective adsorption desulfurization of liquid hydrocarbons. All of three types of the adsorbents exhibit the significant selectivity for sulfur compounds, including alkyl dibenzothiophenes (DBTs), in diesel fuel. Adsorption desulfurization of real diesel fuels (regular diesel fuel (DF), S: 325 ppmw; low sulfur diesel fuel (LSD-I), S: 47 ppmw) over the nickel-based adsorbents (A-2 and A-5) has been conducted at different conditions by using a flowing system. The adsorption capacity of DF over A-2 corresponding to an outlet sulfur level of 30 ppmw is 2.8 mg-S/g-A. The adsorption capacity of LSD-I over A-5 corresponding to the break-through point at 5.0 ppmw sulfur level is 0.35 mg-S/g-A. The spent A-5 can be regenerated by using H2 gas at a flowing rate of 40-50 ml/min, 500 C, and ambient pressure. Adsorption desulfurization of model diesel fuels over metal-sulfide-based adsorbents (A-6-1 and A-6-2) has been conducted at different temperatures to examine the capacity and selectivity of the adsorbents. A regeneration method for the spent metal-sulfide-based adsorbents has been developed. The spent A-6-1 can be easily regenerated by washing the spent adsorbent with a polar solvent followed by heating the adsorbent bed to remove the remainder solvent. Almost all adsorption capacity of the fresh A-6-1 can be recovered after the regeneration. On the other hand, a MCM-41-supported HDS catalyst was developed for deep desulfurization of the refractory sulfur compounds. The results show that the developed MCM-41-supported catalyst demonstrates consistently higher activity for the HDS of the refractory dibenzothiophenic sulfur compounds than the commercial catalyst. On the basis of the fundamental understanding of the adsorptive performance and regeneration natures of the adsorbents, the conceptual design of the novel PSU-SARS process for deep desulfurization of diesel fuel is confirmed and improved further.« less

Method of making tantalum capacitors

DOEpatents

McMillan, April D.; Clausing, Robert E.; Vierow, William F.

1998-01-01

A method for manufacturing tantalum capacitors includes preparing a tantalum compact by cold pressing tantalum powder, placing the compact, along with loose refractory metal powder, in a microwave-transparent casket to form an assembly, and heating the assembly for a time sufficient to effect at least partial sintering of the compact and the product made by the method.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ellingson, W.A.

This broad-base materials engineering program, begun in October 1974, includes studies on both ceramic (refractory) and metallic materials presently being used or intended for use in coal-conversion systems. Appropriate laboratory and field experiments are integrated such that the results have immediate impact on the present pilot-plant and proposed demonstration-plant designs. The report presents the technical accomplishments.

Properties of Epitaxial GaN on Refractory Metal Substrates

DTIC Science & Technology

2007-02-28

Rowland Aymont Technology, Inc., Scotia, New York 12302 Jihyun Kim College of Engineering, Korea University, Seoul 136-701, South Korea Mohammad Fatemi...M. Li, D. Wang, C. Ahyi, C.-C. Tin, J. Williams, and M. Park , Appl. Phys. Lett. 88, 113509 2001. FIG. 4. I-V characteristic of the GaN film on 111

Plasma ARC/SCWO Sysems for Waste-to-Energy Applications Utilizing Milwaste Fuels

DTIC Science & Technology

2013-07-01

configuration and physics 4. Gasification and pollution abatement systems 5. Slag chemistry, refractory design, and glass and metal pouring 6. Energy...Manganese (g/L) 0.07 Nickel (g/L) 0.05 Zinc (g/L) 0.49 GA successfully processed the simulated waste for 6 hours at steady state flow

The electro-thermal stability of tantalum relative to aluminum and titanium in cylindrical liner ablation experiments at 550 kA

NASA Astrophysics Data System (ADS)

Steiner, Adam M.; Campbell, Paul C.; Yager-Elorriaga, David A.; Cochrane, Kyle R.; Mattsson, Thomas R.; Jordan, Nicholas M.; McBride, Ryan D.; Lau, Y. Y.; Gilgenbach, Ronald M.

2018-03-01

Presented are the results from the liner ablation experiments conducted at 550 kA on the Michigan Accelerator for Inductive Z-Pinch Experiments. These experiments were performed to evaluate a hypothesis that the electrothermal instability (ETI) is responsible for the seeding of magnetohydrodynamic instabilities and that the cumulative growth of ETI is primarily dependent on the material-specific ratio of critical temperature to melting temperature. This ratio is lower in refractory metals (e.g., tantalum) than in non-refractory metals (e.g., aluminum or titanium). The experimental observations presented herein reveal that the plasma-vacuum interface is remarkably stable in tantalum liner ablations. This stability is particularly evident when contrasted with the observations from aluminum and titanium experiments. These results are important to various programs in pulsed-power-driven plasma physics that depend on liner implosion stability. Examples include the magnetized liner inertial fusion (MagLIF) program and the cylindrical dynamic material properties program at Sandia National Laboratories, where liner experiments are conducted on the 27-MA Z facility.

Initial Assessment of Environmental Barrier Coatings for the Prometheus Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

M. Frederick

2005-12-15

Depending upon final design and materials selections, a variety of engineering solutions may need to be considered to avoid chemical degradation of components in a notional space nuclear power plant (SNPP). Coatings are one engineered approach that was considered. A comprehensive review of protective coating technology for various space-reactor structural materials is presented, including refractory metal alloys [molybdenum (Mo), tungsten (W), rhenium (Re), tantalum (Ta), and niobium (Nb)], nickel (Ni)-base superalloys, and silicon carbide (Sic). A summary description of some common deposition techniques is included. A literature survey identified coatings based on silicides or iridium/rhenium as the primary methods formore » environmental protection of refractory metal alloys. Modified aluminide coatings have been identified for superalloys and multilayer ceramic coatings for protection of Sic. All reviewed research focused on protecting structural materials from extreme temperatures in highly oxidizing conditions. Thermodynamic analyses indicate that some of these coatings may not be protective in the high-temperature, impure-He environment expected in a Prometheus reactor system. Further research is proposed to determine extensibility of these coating materials to less-oxidizing or neutral environments.« less

Microgravity nucleation and particle coagulation experiments support

NASA Technical Reports Server (NTRS)

Lilleleht, L. U.; Lass, T. J.

1987-01-01

A hollow sphere model is developed to predict the range of supersaturation ratio values for refractory metal vapors in a proposed experimental nucleation apparatus. Since the experiments are to be carried out in a microgravity environment, the model neglects the effects of convection and assumes that the only transfer of vapors through an inert gas atmosphere is by conduction and molecular diffusion. A consistent set of physical properties data is assembled for the various candidate metals and inert ambient gases expected to be used in the nucleation experiments. Transient partial pressure profiles are computed for the diffusing refractory species for two possible temperature distributions. The supersaturation ratio values from both candidate temperature profiles are compared with previously obtained experimetnal data on a silver-hydrogen system. The model is used to simulate the diffusion of magnesium vapor through argon and other inert gas atmospheres over ranges of initial and boundary conditions. These results identify different combinations of design and operating parameters which are liekly to produce supersaturation ratio values high enough to induce homogeneous nucleation in the apparatus being designed for the microgravity nucleation experiments.

A design study of hydrazine and biowaste resistojets

NASA Technical Reports Server (NTRS)

Page, R. J.; Stoner, W. A.; Barker, L.

1986-01-01

A generalized modeling program was adapted in BASIC on a personal computer to compare the performance of four types of biowaste resistojets and two types of hydrazine augmenters. Analyzed biowaste design types were: (1) an electrically conductive ceramic heater-exchanger of zirconia; (2) a truss heater of platinum in cross flow; (3) an immersed bicoiled tubular heater-exchanger; and (4) a nonexposed, refractory metal, radiant heater in a central cavity within a heat exchanger case. Concepts 2 and 3 are designed to have an efficient, stainless steel outer pressure case. The hydrazine design types are: (5) an immersed bicoil heater exchanger and (6) a nonexposed radiant heater now with a refractory metal case. The ceramic biowaste resistojet has the highest specific impulse growth potential at 2000 K of 192.5 (CO2) and 269 s (H2O). The bicoil produces the highest augmenter temperature of 1994 K for a 2073 K heater giving 317 s at .73 overall efficiency. Detailed temperature profiles of each of the designs are shown. The scaled layout drawings of each are presented with recommended materials and fabrication methods.

Nanostructured refractory thin films for solar applications

NASA Astrophysics Data System (ADS)

Ollier, E.; Dunoyer, N.; Dellea, O.; Szambolics, H.

2014-08-01

Selective solar absorbers are key elements of all solar thermal systems. Solar thermal panels and Concentrated Solar Power (CSP) systems aim respectively at producing heat and electricity. In both cases, a surface receives the solar radiation and is designed to have the highest optical absorption (lowest optical reflectivity) of the solar radiation in the visible wavelength range where the solar intensity is the highest. It also has a low emissivity in the infrared (IR) range in order to avoid radiative thermal losses. Current solutions in the state of the art usually consist in deposited interferential thin films or in cermets [1]. Structured surfaces have been proposed and have been simulated because they are supposed to be more efficient when the solar radiation is not normal to the receiving surface and because they could potentially be fabricated with refractory materials able to sustain high operating temperatures. This work presents a new method to fabricate micro/nanostructured surfaces on molybdenum (refractory metal with a melting temperature of 2623°C). This method now allows obtaining a refractory selective surface with an excellent optical selectivity and a very high absorption in the visible range. This high absorption performance was obtained by achieving a double structuration at micro and nano scales thanks to an innovative process flow.

Sunitinib Malate in Treating Younger Patients With Recurrent, Refractory, or Progressive Malignant Glioma or Ependymoma

ClinicalTrials.gov

2015-08-18

Childhood Cerebellar Anaplastic Astrocytoma; Childhood Cerebral Anaplastic Astrocytoma; Childhood Cerebral Astrocytoma; Childhood Infratentorial Ependymoma; Childhood Mixed Glioma; Childhood Oligodendroglioma; Childhood Supratentorial Ependymoma; Recurrent Childhood Cerebellar Astrocytoma; Recurrent Childhood Cerebral Astrocytoma; Recurrent Childhood Ependymoma; Recurrent Childhood Subependymal Giant Cell Astrocytoma

Compatibility of structural materials with liquid bismuth, lead, and mercury

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weeks, J.R.

1996-06-01

During the 1950s and 1960s, a substantial program existed at Brookhaven National Laboratory as part of the Liquid Metal Fuel reactor program on the compatibility of bismuth, lead, and their alloys with structural materials. Subsequently, compatibility investigations of mercury with structural materials were performed in support of development of Rankine cycle mercury turbines for nuclear applications. The present talk will review present understanding of the corrosion/mass-transfer reactions of structural materials with these liquid metal coolants. Topics to be discussed include the basic solubility relationships of iron, chromium, nickel, and refractory metals in these liquid metals, the results of inhibition studies,more » the role of oxygen on the corrosion processes, and specialized topics such as cavitation-corrosion and liquid metal embrittlement. Emphasis will be placed on utilizing the understanding gained in this earlier work on the development of heavy liquid metal targets in spallation neutron sources.« less

Mineral resources of Novokuznetsk administrative district of Kemerovo region (metallic and non-metallic minerals)

NASA Astrophysics Data System (ADS)

Gutak, Ja M.

2017-09-01

The article summarizes data on metallic and non-metallic minerals of Novokuznetsk district of Kemerovo region. Consistently reviewed are iron deposits (Tersinskaya group of deposits), gold deposits (placer accumulations and vein gold deposits), mineral water deposits (Tersinskoe deposit), deposit of refractory clay (Barkinskoe) and wide spread mineral deposits such as brick clay, keramzite materials, sand and gravel, building stones, ornamental stones, facing stones, peat, materials for lime production. It is indicated that resource base of metallic and nonmetallic minerals is inferior to that of mineral coal. At the same time it can be of considerable interest to small and medium-size businesses as objects with quick return of investment (facing and ornamental stones). For a number of wide spread mineral resources (brick clay, keramzite materials, sand and gravel) it is an important component of local industry.

Management of refractory pityriasis rubra pilaris: challenges and solutions

PubMed Central

Moretta, Gaia; De Luca, Erika V; Di Stefani, Alessandro

2017-01-01

Pityriasis rubra pilaris (PRP) is a rare chronic inflammatory papulosquamous skin disease. Its clinical presentation and evolution is very variable. The most frequent clinical features are follicular papules, progressing to yellow-orange erythroderma with round small areas of normal skin and the well-demarcated palmoplantar keratoderma. Actually, six different types of PRP have been described based on clinical characteristics, age of onset, and prognosis. The pathogenesis is still unknown, and treatment can be challenging. Available treatments are mainly based on case reports or case series of clinical experience because no controlled randomized trials have never been performed because of the rarity of the condition. Traditional systemic treatment consists in retinoids, which are actually considered as first-line therapy, but refractory cases that do not respond or relapse after drug interruption do exist. In recent years, numerous reports have demonstrated the efficacy of new agents such as biological drugs. This article is an overview on available therapeutic options, in particular for refractory forms of PRP. PMID:29184428

Immunomodulatory therapy in refractory/recurrent ovarian cancer.

PubMed

Chen, Chao-Yu; Lai, Chyong-Huey; Yang, Lan-Yan; Tang, Yun-Hsin; Chou, Hung-Hsueh; Chang, Chee-Jen; Lin, Cheng-Tao

2015-04-01

To investigate the efficacy and toxicity of immunomodulatory therapy (IMT) alone or as an add-on to palliative/salvage chemotherapy in patients with refractory/recurrent epithelial ovarian cancer (EOC). We retrospectively analyzed the efficacy and toxicity of IMT in 15 patients with refractory/recurrent EOC who had previously received multiple chemotherapy regimens. The median age of the patients was 56 years (range, 41-75 years). Three patients were platinum-sensitive, two were platinum-resistant, and the remaining 10 patients were refractory to platinum-based front-line chemotherapy. IMT consisted of picibanil (OK-432) on Day 1, interleukin-2 and/or interferon-α on Day 2 administered by subcutaneous injection (every week or 2-weekly). Five patients never received metronomic oral cyclophosphamide. After IMT, three patients achieved partial remission (PR, lasting for 11 months, ≥ 12 months, and 16 months), and six patients had stable disease (SD). The disease stabilizing rate (PR+SD) was 60% (3/3 in platinum-sensitive and 6/12 in platinum-resistant/refractory patients). The absolute lymphocyte count (ALC) at 1 month after IMT was significantly higher in the PR+SD group (median 1242.0/μL) than in the progression group (median 325.0/μL) (p = 0.012). No ≥ Grade 3 toxicities were observed. The median post-IMT survival time was 12 months (range, 2-39 months). IMT alone or add-on to palliative/salvage chemotherapy for refractory/recurrent EOC achieves a substantial disease stabilizing rate without severe toxicity, which might be a potential option in selected patients. The ALC 1 month after IMT could be an early indicator to disease stabilization. Copyright © 2015. Published by Elsevier B.V.

LINX®, a novel treatment for patients with refractory asthma complicated by gastroesophageal reflux disease: a case report.

PubMed

Sriratanaviriyakul, Narin; Kivler, Celeste; Vidovszky, Tamas J; Yoneda, Ken Y; Kenyon, Nicholas J; Murin, Susan; Louie, Samuel

2016-05-24

Gastroesophageal reflux disease is one of the most common comorbidities in patients with asthma. Gastroesophageal reflux disease can be linked to difficult-to-control asthma. Current management includes gastric acid suppression therapy and surgical antireflux procedures. The LINX® procedure is a novel surgical treatment for patients with gastroesophageal reflux disease refractory to medical therapy. To the best of our knowledge, we report the first case of successful treatment of refractory asthma secondary to gastroesophageal reflux disease using the LINX® procedure. Our patient was a 22-year-old white woman who met the American Thoracic Society criteria for refractory asthma that had remained poorly controlled for 5 years despite progressive escalation to step 6 treatment as recommended by National Institutes of Health-National Asthma Education and Prevention Program guidelines, including high-dose oral corticosteroids, high-dose inhaled corticosteroid plus long-acting β2-agonist, leukotriene receptor antagonist, and monthly omalizumab. Separate trials with azithromycin therapy and roflumilast did not improve her asthma control, nor did bronchial thermoplasty help. Additional consultations with two other university health systems left the patient with few treatment options for asthma, which included cyclophosphamide. Instead, the patient underwent a LINX® procedure after failure of maximal medical therapy for gastroesophageal reflux disease with the additional aim of improving asthma control. After she underwent LINX® treatment, her asthma improved dramatically and was no longer refractory. She had normal exhaled nitric oxide levels and loss of peripheral eosinophilia after LINX® treatment. Prednisone was discontinued without loss of asthma control. The only immediate adverse effects due to the LINX® procedure were bloating, nausea, and vomiting. LINX® is a viable alternative to the Nissen fundoplication procedure for the treatment of patients with gastroesophageal reflux disease and poorly controlled concomitant refractory asthma.

Rapidly-progressive catatonia responsive to zolpidem in a patient with ovarian teratoma-associated paraneoplastic encephalitis.

PubMed

Amorim, Edilberto; McDade, Eric M

2016-08-01

Psychiatric symptoms and catatonia are key components of the clinical presentation of paraneoplastic encephalitis; additionally symptoms can be long-lasting and often difficult to treat. We report a 73-year-old patient with rapidly progressive catatonia not responsive to immunotherapy, tumor resection, electroconvulsive therapy, or benzodiazepines who had significant improvement after zolpidem administration. This report suggests that zolpidem is an option in the treatment of patients with refractory catatonia and paraneoplastic encephalitis. Copyright © 2016 Elsevier Ltd. All rights reserved.

Hematopoietic stem cell transplantation for non-Hodgkin lymphoma.

PubMed

Bhatt, Vijaya Raj; Vose, Julie M

2014-12-01

Up-front rituximab-based chemotherapy has improved outcomes in non-Hodgkin lymphoma (NHL); refractory or relapsed NHL still accounts for approximately 18,000 deaths in the United States. Autologous hematopoietic stem cell transplantation (SCT) can improve survival in primary refractory or relapsed aggressive NHL and mantle cell lymphoma and in relapsed follicular or peripheral T-cell lymphoma. Autologous SCT as a consolidation therapy after first complete or partial remission in high-risk aggressive NHL, mantle cell lymphoma, and peripheral T-cell lymphoma may improve progression-free survival. Allogeneic SCT offers a lower relapse rate but a higher nonrelapse mortality resulting in overall survival similar to autologous SCT. Copyright © 2014 Elsevier Inc. All rights reserved.

Effect of Rice Husk Ash Insulation Powder on the Reoxidation Behavior of Molten Steel in Continuous Casting Tundish

NASA Astrophysics Data System (ADS)

Kim, Tae Sung; Chung, Yongsug; Holappa, Lauri; Park, Joo Hyun

2017-06-01

Rice husk ash (RHA) has been widely used as an insulation powder in steel casting tundish. Its effect on the reoxidation of molten steel in tundish as well as on the corrosion of magnesia refractory was investigated. The reoxidation of the steel, indicated by an oxygen pickup, was progressed by increasing the ratio of RHA to the sum of RHA and carryover ladle slag ( R ratio) greater than about 0.2. The increase of the silica activity in the slag layer promoted the self-dissociation of SiO2 from the slag layer into the molten steel, resulting in the silicon and oxygen pickup as the R ratio increased. The total number of reoxidation inclusions dramatically increased and the relative fraction of Al2O3-rich inclusions increased by increasing the R ratio. Hence, the reoxidation of molten steel in tundish might become more serious due to the formation of alumina-rich inclusions as the casting sequence increases. MgO in the refractory directly dissolved into the molten slag layer without forming any intermediate compound layer ( e.g., spinel), which is a completely different situation from the general slag-refractory interfacial reaction. A flow was possibly induced by the bursting of gas bubbles at the ash-slag (-refractory) interface, since the silica in the RHA powder continuously dissolved into the molten slag pool. Thus, the RHA insulation powder has a negative effect on the corrosion of MgO refractory.

Allogeneic hematopoietic stem cell transplantation for severe, refractory juvenile idiopathic arthritis

PubMed Central

Ladomenou, Fani; Carpenter, Ben; Chandra, Sharat; Sedlacek, Petr; Formankova, Renata; Grandage, Vicky; Friswell, Mark; Cant, Andrew J.; Nademi, Zohreh; Slatter, Mary A.; Gennery, Andrew R.; Hambleton, Sophie; Flood, Terence J.; Lucchini, Giovanna; Chiesa, Robert; Rao, Kanchan; Amrolia, Persis J.; Brogan, Paul; Wedderburn, Lucy R.; Glanville, Julie M.; Hough, Rachael; Marsh, Rebecca; Abinun, Mario; Veys, Paul

2018-01-01

Patients with juvenile idiopathic arthritis (JIA) can experience a severe disease course, with progressive destructive polyarthritis refractory to conventional therapy with disease-modifying antirheumatic drugs including biologics, as well as life-threatening complications including macrophage activation syndrome (MAS). Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a potentially curative immunomodulatory strategy for patients with such refractory disease. We treated 16 patients in 5 transplant centers between 2007 and 2016: 11 children with systemic JIA and 5 with rheumatoid factor–negative polyarticular JIA; all were either refractory to standard therapy, had developed secondary hemophagocytic lymphohistiocytosis/MAS poorly responsive to treatment, or had failed autologous HSCT. All children received reduced toxicity fludarabine-based conditioning regimens and serotherapy with alemtuzumab. Fourteen of 16 patients are alive with a median follow-up of 29 months (range, 2.8-96 months). All patients had hematological recovery. Three patients had grade II-IV acute graft-versus-host disease. The incidence of viral infections after HSCT was high, likely due to the use of alemtuzumab in already heavily immunosuppressed patients. All patients had significant improvement of arthritis, resolution of MAS, and improved quality of life early following allo-HSCT; most importantly, 11 children achieved complete drug-free remission at the last follow-up. Allo-HSCT using alemtuzumab and reduced toxicity conditioning is a promising therapeutic option for patients with JIA refractory to conventional therapy and/or complicated by MAS. Long-term follow-up is required to ascertain whether disease control following HSCT continues indefinitely. PMID:29618462

Long-term outcomes for patients with chronic lymphocytic leukemia who discontinue ibrutinib.

PubMed

Jain, Preetesh; Thompson, Philip A; Keating, Michael; Estrov, Zeev; Ferrajoli, Alessandra; Jain, Nitin; Kantarjian, Hagop; Burger, Jan A; O'Brien, Susan; Wierda, William G

2017-06-15

Ibrutinib is a Bruton tyrosine kinase inhibitor and is approved for the treatment of patients with chronic lymphocytic leukemia (CLL) in frontline and relapsed/refractory settings. The authors previously reported poor outcomes for patients who discontinued ibrutinib; however, long-term outcomes were not reported. Data from 320 patients who received ibrutinib on clinical studies between 2010 and 2015 at The University of Texas MD Anderson Cancer Center were retrospectively analyzed. Long-term outcomes among patients with CLL after they discontinued ibrutinib were analyzed. Ninety of 320 patients (28%) who were treated on ibrutinib-based regimens discontinued ibrutinib. Of these, 80 had relapsed/refractory disease, and 10 were treatment-naive. The median time to discontinuation was 15 months (range, 1.2-54 months). After a median follow-up of 38 months after starting ibrutinib, 40 patients (44%) remained alive. Major reasons for ibrutinib discontinuation were intolerance (n = 29; 32%), miscellaneous (n = 28; 31%), progression (n = 19; 21%), and Richter transformation (RT) (n = 9; 10%). The median survival according to the reason for discontinuation was 33 months for ibrutinib intolerance, 11 months for miscellaneous causes, 16 months for progressive CLL, and 2 months for RT. Among the 19 patients who had progressive CLL, 42% responded to subsequent therapy. Ibrutinib discontinuation was observed during therapy. Patients with CLL who had disease transformation had especially poor outcomes, whereas those who developed progressive disease during ibrutinib therapy had a median survival of <1.5 years. Survival was associated with the reason for discontinuation; patients who had progressive CLL had better survival compared with those who had disease transformation. Effective salvage strategies for patients with CLL who progress on ibrutinib therapy is of critical importance. Cancer 2017;123:2268-2273. © 2017 American Cancer Society. © 2017 American Cancer Society.

Steel bonded dense silicon nitride compositions and method for their fabrication

DOEpatents

Landingham, R.L.; Shell, T.E.

1985-05-20

A two-stage bonding technique for bonding high density silicon nitride and other ceramic materials to stainless steel and other hard metals, and multilayered ceramic-metal composites prepared by the technique are disclosed. The technique involves initially slurry coating a surface of the ceramic material at about 1500/sup 0/C in a vacuum with a refractory material and the stainless steel is then pressure bonded to the metallic coated surface by brazing it with nickel-copper-silver or nickel-copper-manganese alloys at a temperature in the range of about 850/sup 0/ to 950/sup 0/C in a vacuum. The two-stage bonding technique minimizes the temperature-expansion mismatch between the dissimilar materials.

Steel bonded dense silicon nitride compositions and method for their fabrication

DOEpatents

Landingham, Richard L.; Shell, Thomas E.

1987-01-01

A two-stage bonding technique for bonding high density silicon nitride and other ceramic materials to stainless steel and other hard metals, and multilayered ceramic-metal composites prepared by the technique are disclosed. The technique involves initially slurry coating a surface of the ceramic material at about 1500.degree. C. in a vacuum with a refractory material and the stainless steel is then pressure bonded to the metallic coated surface by brazing it with nickel-copper-silver or nickel-copper-manganese alloys at a temperature in the range of about 850.degree. to 950.degree. C. in a vacuum. The two-stage bonding technique minimizes the temperature-expansion mismatch between the dissimilar materials.

IMPACT OF PRETRANSPLANT CONDITIONING REGIMENS ON OUTCOMES OF ALLOGENEIC TRANSPLANTATION FOR CHEMOTHERAPY-UNRESPONSISVE DIFFUSE LARGE B-CELL LYMPHOMA AND GRADE-III FOLLICULAR LYMPHOMA

PubMed Central

Hamadani, Mehdi; Saber, Wael; Ahn, Kwang Woo; Carreras, Jeanette; Cairo, Mitchell S.; Fenske, Timothy S.; Gale, Robert Peter; Gibson, John; Hale, Gregory A.; Hari, Parameswaran N.; Hsu, Jack W.; Inwards, David J.; Kamble, Rammurti T.; Klein, Anderas; Maharaj, Dipnarine; Marks, David I.; Rizzieri, David A.; Savani, Bipin N.; Schouten, Harry C.; Waller, Edmund K.; Wirk, Baldeep; Laport, Ginna G.; Montoto, Silvia; Maloney, David G.; Lazarus, Hillard M.

2013-01-01

Patients with chemorefractory non-Hodgkin lymphomas (NHL) generally have a poor prognosis. We used the observational database of the CIBMTR to study the outcome of 533 patients with refractory diffuse large B-cell lymphoma (DLBCL) or grade-III follicular lymphoma (FL-III) who underwent allogeneic transplantation (allo-HCT) using either myeloablative (MA; N=307) or reduced intensity/non-myeloablative conditioning (RIC/NST; N=226), between 1998-2010. We analyzed non-relapse mortality (NRM), relapse/progression, progression-free survival (PFS), and overall survival (OS). Only 45% of the patients at transplant had a Karnofsky performance score of ≥90%. Median follow-up of surviving patients after MA and RIC/NST allo-HCT is 35 months and 30 months, respectively. At 3years, MA allo-HCT was associated with a higher NRM compared to RIC/NST (53% vs. 42%; p=0.03), similar PFS (19% vs. 23%; p=0.40), and lower OS (19% vs. 28%; p=0.02), respectively. On multivariate analysis, FL-III histology was associated with lower NRM (relative-risk [RR]=0.52), reduced risk of relapse/progression (RR=0.42), superior PFS (RR=0.51) and OS (RR=0.53), while MA conditioning was associated with reduced risk of relapse/progression (RR=0.66). Despite a refractory state, a small subset of DLBCL and FL-III patients can attain durable remissions after allo-HCT. Conditioning regimen intensity was not associated with PFS and OS despite a higher risk of relapse/progression with RIC/NST allo-HCT. PMID:23380340

Clinical Course of Six Children With GNAO1 Mutations Causing a Severe and Distinctive Movement Disorder.

PubMed

Ananth, Amitha L; Robichaux-Viehoever, Amy; Kim, Young-Min; Hanson-Kahn, Andrea; Cox, Rachel; Enns, Gregory M; Strober, Jonathan; Willing, Marcia; Schlaggar, Bradley L; Wu, Yvonne W; Bernstein, Jonathan A

2016-06-01

Mutations in GNAO1 have been described in 11 patients to date. Although most of these individuals had epileptic encephalopathy, four patients had a severe movement disorder as the prominent feature. We describe the largest series of patients with de novoGNAO1 mutations who have severe chorea, developmental delay, and hypotonia in the absence of epilepsy. Six patients with recurrent missense mutations in GNAO1 as detected by whole exome sequencing were identified at three institutions. We describe the presentation, clinical course, and response to treatment of these patients. All six patients exhibited global developmental delay and hypotonia from infancy. Chorea developed by age four years in all but one patient, who developed chorea at 14 years. Treatments with neuroleptics and tetrabenazine were most effective in the baseline management of chorea. The chorea became gradually progressive and marked by episodes of severe, refractory ballismus requiring intensive care unit admissions in four of six patients. Exacerbations indirectly led to the death of two patients. Patients with GNAO1 mutations can present with a severe, progressive movement disorder in the absence of epilepsy. Exacerbations may be refractory to treatment and can result in life-threatening secondary complications. Early and aggressive treatment of these exacerbations with direct admission to intensive care units for treatment with anesthetic drips may prevent some secondary complications. However the chorea and ballismus can be refractory to maximum medical therapy. Copyright © 2016 Elsevier Inc. All rights reserved.

Clinical activity of everolimus in relapsed/refractory marginal zone B-cell lymphomas: results of a phase II study of the International Extranodal Lymphoma Study Group.

PubMed

Conconi, Annarita; Raderer, Markus; Franceschetti, Silvia; Devizzi, Liliana; Ferreri, Andrés J M; Magagnoli, Massimo; Arcaini, Luca; Zinzani, Pier Luigi; Martinelli, Giovanni; Vitolo, Umberto; Kiesewetter, Barbara; Porro, Elena; Stathis, Anastasios; Gaidano, Gianluca; Cavalli, Franco; Zucca, Emanuele

2014-07-01

The International Extranodal Lymphoma Study Group coordinated a phase II trial to evaluate the activity and safety of everolimus in marginal zone lymphomas (MZLs). Thirty patients with relapsed/refractory MZLs received everolimus for six cycles or until dose-limiting toxicity or progression. Median age was 71 years (range, 51-88 years). Twenty patients had extranodal, six splenic, four nodal MZL. Twenty-four patients had stage III-IV. Median number of prior therapies was two (range 1-5). Seventeen patients had early treatment discontinuation, in most cases due to toxicity. Median number of cycles was 4.5 (range, 1-16). Among the 24 assessable patients, the overall response rate (ORR) was 25% (95% confidence interval: 10-47). Grade 3-4 adverse events were neutropenia and thrombocytopenia (17% of patients, each), infections (17%), mucositis and odontogenic infections (13%) and lung toxicity (3%). The median response duration was 6.8 months (range, 1.4-11.1+). After a median follow-up of 14.5 months, five deaths were reported: four deaths were due to lymphoma, one was due to toxicity. In an intent-to-treat analysis, the projected median progression-free survival was 14 months. The moderate antitumour activity of everolimus in relapsed/refractory MZLs and the observed toxicity limit its therapeutical applicability in these indolent entities. Lower doses of the drug and, perhaps, different strategies including combination with additional agents need to be explored. © 2014 John Wiley & Sons Ltd.

Seizure clusters: characteristics and treatment.

PubMed

Haut, Sheryl R

2015-04-01

Many patients with epilepsy experience 'clusters' or flurries of seizures, also termed acute repetitive seizures (ARS). Seizure clustering has a significant impact on health and quality of life. This review summarizes recent advances in the definition and neurophysiologic understanding of clustering, the epidemiology and risk factors for clustering and both inpatient and outpatient clinical implications. New treatments for seizure clustering/ARS are perhaps the area of greatest recent progress. Efforts have focused on creating a uniform definition of a seizure cluster. In neurophysiologic studies of refractory epilepsy, seizures within a cluster appear to be self-triggering. Clinical progress has been achieved towards a more precise prevalence of clustering, and consensus guidelines for epilepsy monitoring unit safety. The greatest recent advances are in the study of nonintravenous route of benzodiazepines as rescue medications for seizure clusters/ARS. Rectal benzodiazepines have been very effective but barriers to use exist. New data on buccal, intramuscular and intranasal preparations are anticipated to lead to a greater number of approved treatments. Progesterone may be effective for women who experience catamenial clusters. Seizure clustering is common, particularly in the setting of medically refractory epilepsy. Clustering worsens health and quality of life, and the field requires greater focus on clarifying of definition and clinical implications. Progress towards the development of nonintravenous routes of benzodiazepines has the potential to improve care in this area.

Long-term adequacy of metal resources

USGS Publications Warehouse

Singer, D.A.

1977-01-01

Although the earth's crust contains vast quantities of metals, extraction technologies and associated costs are inextricably bound to three fundamental geological factors - the amount of metal available in the earth's crust in each range of grades, the mineralogical form and chemical state of the metal, and the spatial distribution of the metal. The energy required to recover a given amount of metal increases substantially as grade declines. Most metal is produced from sulphide or oxide minerals, whereas most metal in the crust may be locked in the structures of the more refractory silicates. Recovery from silicate minerals could require orders of magnitude more energy than that used at present as also could exploitation of small, widely scattered or thin, deeply buried deposits. Although specific information on the fundamental factors is not available, each factor must in turn tend to further restrict exploitation. Independence of average grade and tonnage for many deposit types further reduces the availability of rock as a source of metal. In the long term, effects of these factors will be large increases in price for many metals. ?? 1977.

Clinical Outcomes, Efficacy, and Adverse Events in Patients Undergoing Esophageal Stent Placement for Benign Indications: A Large Multicenter Study.

PubMed

Suzuki, Takayuki; Siddiqui, Ali; Taylor, Linda J; Cox, Kristen; Hasan, Raza A; Laique, Sobia N; Mathew, Arun; Wrobel, Piotr; Adler, Douglas G

2016-01-01

Esophageal stents are commonly used to treat benign esophageal conditions including refractory benign esophageal strictures, anastomotic strictures, fistulae, perforations and anastomotic leaks. Data on outcomes in these settings remain limited. We performed a retrospective multicenter study of patients who underwent fully or partially covered self-expandable stent placement for benign esophageal diseases. Esophageal stent placements were performed for the following indications: (1) benign refractory esophageal strictures, (2) surgical anastomotic strictures, (3) esophageal perforations, (4) esophageal fistulae, and (5) surgical anastomotic leaks. A total of 70 patients underwent esophageal stent placement for benign esophageal conditions. A total of 114 separate procedures were performed. The most common indication for esophageal stent placement was refractory benign esophageal stricture (48.2%). Global treatment success rate was 55.7%. Treatment success rate was 33.3% in refractory benign strictures, 23.1% in anastomotic strictures, 100% in perforations, 71.4% in fistulae, and 80% in anastomotic leaks. Stent migration was noted in 28 of 70 patients (40%), most commonly seen in refractory benign strictures. This is one of the largest studies to date of esophageal stents to treat benign esophageal diseases. Success rates are lowest in benign esophageal strictures. These patients have few other options beyond chronic dilations, feeding tubes, and surgery, and fully covered self-expandable metallic stent give patients a chance to have their problem fixed endoscopically and still eat by mouth. Perforations, fistulas, and leaks respond very well to esophageal stenting, and stenting should be considered as a first-line therapy in these settings.

40 CFR 471.53 - New source performance standards (NSPS).

Code of Federal Regulations, 2013 CFR

2013-07-01

....5 to 10.0 at all times. (n) Alkaline cleaning spent baths. Subpart E—NSPS Pollutant or pollutant... refractory metals alkaline cleaned Copper 0.428 0.204 Nickel .184 0.124 Fluoride 19.9 8.82 Molybdenum 1.68 0.... (o) Alkaline cleaning rinse. Subpart E—NSPS Pollutant or pollutant property Maximum for any 1 day...

Covered metal stent or multiple plastic stents for refractory pancreatic ductal strictures in chronic pancreatitis: a systematic review.

PubMed

Shen, Yonghua; Liu, Mingdong; Chen, Min; Li, Yunhong; Lu, Ying; Zou, Xiaoping

2014-01-01

Refractory chronic pancreatitis has been proposed as a challenge for endoscopists following routine single plastic stenting. However, data on the efficacy and safety of further endoscopic stenting are still controversial. The current systematic review aimed to assess the efficacy and safety of placement of fully covered self-expandable metal stent (FCSEMS) and multiple plastic stents. Databases including MEDLINE, EMBASE, the Cochrane Library, CBM, CNKI, VIP, and WANFANG Database were used to search relevant trials. Published studies were assessed by using well-defined inclusion and exclusion criteria. The process was independently performed by two investigators. A total of 5 studies provided data of 80 patients. Forest plots and publication bias were not carried out because few studies were relevant and screened studies were all case series. The technical success rate was 100% both in placement of FCSEMS and multiple plastic stents. The functional success rate after placement of FCSEMS was 100%, followed by multiple plastic stents (94.7%). Complications occurred 26.2% after FCSEMS placement, which was not described in detail in multiple plastic stents. The stent migration rate was 8.2% for FCSEMS and 10.5% for multiple plastic stents. Reintervention rate was 9.8% for FCSEMS and 15.8% for multiple plastic stents. Pain improvement rate was 85.2% for FCSEMS and 84.2% for multiple plastic stents. FCSEMS appeared to be no significant difference with multiple plastic stents in treatment of refractory chronic pancreatitis. We need to develop more investigations. Copyright © 2014 IAP and EPC. Published by Elsevier B.V. All rights reserved.

Refractory Pain Management in Amyloid-Associated Peripheral Neuropathy.

PubMed

Warner, Nafisseh S; Watson, James C; Bendel, Markus A; Moeschler, Susan M

2018-05-01

Systemic amyloidosis is a disease that often involves multiple organ systems, including the peripheral nervous system. Patients may present with severe, refractory neuropathic pain; however, the optimal treatment approach for pain for these patients remains unclear. A man with severe, refractory neuropathic pain in his bilateral upper and lower extremities and the trunk secondary to amyloid neuropathy is presented. Multiple medication trials, including neuropathic and opioid agents, produced considerable adverse effects and minimal relief. Scrambler therapy, a novel electrical stimulation modality, was used and was associated with substantial short-term but nonsustained benefit. Spinal cord stimulation was considered, but given his diffuse symptoms, it was deemed a less-than-optimal approach. Ultimately, an intrathecal drug delivery system was placed with infusion of hydromorphone, resulting in substantial pain reduction in all involved areas and with an improved adverse effect profile. This intervention resulted in immense improvement in the patient's quality of life, despite progression of his systemic amyloidosis. Severe pain in the setting of amyloid neuropathy is often difficult to treat. To our knowledge, this represents the first report of Scrambler therapy or an implanted intrathecal drug delivery system used for a patient with refractory amyloidosis-related neuropathic pain, resulting in substantial analgesic benefit and improved quality of life.

The use of high-dose insulin therapy and intravenous lipid emulsion to treat severe, refractory diltiazem toxicosis in a dog.

PubMed

Maton, Barbara L; Simmonds, Erin E; Lee, Justine A; Alwood, Amy J

2013-01-01

To describe the novel use of high-dose insulin (HDI) therapy and intravenous lipid emulsion (ILE) to treat refractory, severe diltiazem toxicosis in a dog. A 4-year-old Pomeranian was presented for treatment 2.5 hours following ingestion of a diltiazem extended-release capsule. Toxic ingestion was calculated at a maximum exposure of 79 mg/kg, with a reported canine LD50 of 50 mg/kg. Clinical signs of progressive hypotension and severe bradycardia with atrial standstill were observed, which persisted despite treatment with atropine, calcium, glucagon, and dopamine. The novel use of HDI and ILE as part of therapy for diltiazem toxicosis resulted in clinical resolution of life-threatening signs. Within 1 hour of initiating HDI therapy, the clinical signs improved, and with continued treatment, the patient remained normotensive and survived to discharge. To the authors' knowledge, this is the first reported clinical case describing the use of both HDI and ILE therapy in the treatment of severe refractory diltiazem toxicosis in veterinary medicine. No significant adverse effects were observed from the treatment. In veterinary patients with severe refractory calcium channel blocker toxicosis, the use of HDI and ILE should be considered for life-threatening clinical signs. © Veterinary Emergency and Critical Care Society 2013.

Classical Hodgkin's lymphoma: the Lymphoma Study Association guidelines for relapsed and refractory adult patients eligible for transplant.

PubMed

Van Den Neste, Eric; Casasnovas, Olivier; André, Marc; Touati, Mohamed; Senecal, Delphine; Edeline, Véronique; Stamatoullas, Aspasia; Fornecker, Luc; Deau, Bénédicte; Gastinne, Thomas; Reman, Oumédaly; Gaillard, Isabelle; Borel, Cécile; Brice, Pauline; Fermé, Christophe

2013-08-01

The Hodgkin's Lymphoma Committee of the Lymphoma Study Association (LYSA) gathered in 2012 to prepare guidelines on the management of transplant-eligible patients with relapsing or refractory Hodgkin's lymphoma. The working group is made up of a multidisciplinary panel of experts with a significant background in Hodgkin's lymphoma. Each member of the panel of experts provided an interpretation of the evidence and a systematic approach to obtain consensus was used. Grades of recommendation were not required since levels of evidence are mainly based on phase II trials or standard practice. Data arising from randomized trials are emphasized. The final version was endorsed by the scientific council of the LYSA. The expert panel recommends a risk-adapted strategy (conventional treatment, or single/double transplantation and/or radiotherapy) based on three risk factors at progression (primary refractory disease, remission duration < 1 year, stage III/IV), and an early evaluation of salvage chemosensitivity, including (18)fluorodeoxy glucose-positron emission tomography interpreted according to the Deauville scoring system. Most relapsed or refractory Hodgkin's lymphoma patients chemosensitive to salvage should receive high-dose therapy and autologous stem-cell transplantation as standard. Efforts should be made to increase the proportion of chemosensitive patients by alternating non-cross-resistant chemotherapy lines or exploring the role of novel drugs.

Chemical fractionation in the solar nebula

NASA Technical Reports Server (NTRS)

Grossman, L.

1977-01-01

The sequence of condensation of minerals from a cooling gas of solar composition has been calculated from thermodynamic data over the pressure range 0.001-0.00001 atm, assuming that complete chemical equilibrium is maintained. The results suggest that the Ca-Al-rich inclusions Allende and other carbonaceous chondrites are aggregates of the highest temperature condensates. Complete condensation of these elements is followed, 100 deg later, by the onset of the crystallization of nickel-iron, forsterite and enstatite. Transport of Ca-Al-rich refractory condensates from one part of the nebula to another before the condensation of these lower-temperature phases may have been responsible for the refractory element fractionations between the different classes of chondrites and possibly for the inferred refractory element enrichment of the Moon. The temperature gap between the condensation temperatures of nickel-iron and forsterite increases with increasing total pressure. Because pressure and temperature probably increased with decreasing heliocentric distance in the solar nebula, Mercury may have accreted from a condensate assemblage having a higher metal/silicate ratio than Venus or Earth which may, in turn, have formed from less oxidized material than Mars.

Nucleation and particle coagulation experiments in microgravity

NASA Technical Reports Server (NTRS)

Nuth, J.

1987-01-01

Measurements of the conditions under which carbon, aluminum oxide, and silicon carbide smokes condense and of the morphology and crystal structure of the resulting grains are essential if the nature of the materials ejected into the interstellar medium and the nature of the grains which eventually became part of the proto solar nebular are to be understood. Little information is currently available on the vapor-solid phase transitions of refractory metals and solids. What little experimental data do exist are, however, not in agreement with currently accepted models of the nucleation process for more volatile materials. The major obstacle to performing such experiments in earth-based laboratories is the susceptibility of these systems to convection. Evaporation of refractory materials into a low-pressure environment with a carefully controlled temperature gradient will produce refractory smokes when the critical supersaturation of the system is exceeded. Measurement of the point at which nucleation occurs, via light scattering or extinction, can not only yield nucleation data but also, information on the chemical composition and crystal structure of the condensate. Experimental requirements are presented.

Better VPS Fabrication of Crucibles and Furnace Cartridges

NASA Technical Reports Server (NTRS)

Holmes, Richard R.; Zimmerman, Frank R.; O'Dell, J. Scott; McKechnie, Timothy N.

2003-01-01

An experimental investigation has shown that by (1) vacuum plasma spraying (VPS) of suitable refractory metal alloys on graphite mandrels, and then (2) heat-treating the VPS alloy deposits under suitable conditions, it is possible to fabricate improved crucibles and furnace cartridges that could be used at maximum temperatures between 1,400 and 1,600 C and that could withstand chemical attack by the materials to be heated in the crucibles and cartridges. Taken by itself, the basic concept of fabricating furnace cartridges by VPS of refractory materials onto graphite mandrels is not new; taken by itself, the basic concept of heat treatment of VPS deposits for use as other than furnace cartridges is also not new; however, prior to this investigation, experimental crucibles and furnace cartridges fabricated by VPS had not been heat treated and had been found to be relatively weak and brittle. Accordingly, the investigation was directed toward determining whether certain combinations of (1) refractory alloy compositions, (2) VPS parameters, and (3) heat-treatment parameters could result in VPS-fabricated components with increased ductility.

Biomining-biotechnologies for extracting and recovering metals from ores and waste materials.

PubMed

Johnson, D Barrie

2014-12-01

The abilities of acidophilic chemolithotrophic bacteria and archaea to accelerate the oxidative dissolution of sulfide minerals have been harnessed in the development and application of a biotechnology for extracting metals from sulfidic ores and concentrates. Biomining is currently used primarily to leach copper sulfides and as an oxidative pretreatment for refractory gold ores, though it is also used to recover other base metals, such as cobalt, nickel and zinc. Recent developments have included using acidophiles to process electronic wastes, to extract metals from oxidized ores, and to selectively recover metals from process waters and waste streams. This review describes the microorganisms and mechanisms involved in commercial biomining operations, how the technology has developed over the past 50 years, and discusses the challenges and opportunities for mineral biotechnologies in the 21st century. Copyright © 2014 Elsevier Ltd. All rights reserved.

Numerical investigation of melting and solidification processes in modified surface layers of metal at induction heating

NASA Astrophysics Data System (ADS)

Shchukin, V. G.; Popov, V. N.

2017-10-01

One of the perspective ways to improve the operational properties of parts of machines during induction treatment of their surfaces is the modification of the melt by specially prepared nanoscale particles of refractory compounds (carbides, nitrides, carbonitrides, etc.). This approach allows us to increase the number of crystallization centers and to refine the structural components of the solidified metal. The resulting high dispersity and homogeneity of crystalline grains favorably affect the quality of the treated surfaces. 3D numerical simulation of thermophysical processes in the modification of the surface layer of metal in a moving substrate was carried out. It is assumed that the surface of the substrate is covered with a layer of specially prepared nanoscale particles of a refractory compound, which, upon penetration into the melt, are uniformly distributed in it. The possibility of applying a high-frequency electromagnetic field of high power for heating and melting of a metal (iron) for the purpose of its subsequent modification is investigated. The distribution of electromagnetic energy in the metal is described by empirical formulas. Melting of the metal is considered in the Stefan approximation, and upon solidification it is assumed that all nanoparticles serve as centers for volume-sequential crystallization. Calculations were carried out with the following parameters: specific power p0 = 35 and 40 kW/cm2 at frequency f = 440 and 1200 kHz, the substrate velocity V = 0.5-2.5 cm/s, the nanoparticles' size is 50 nm and concentration Np = 2.0 . 109 cm-3. Based on the results obtained in a quasi-stationary formulation, the distribution of the temperature field, the dimensions of the melting and crystallization zones, the change in the solid fraction in the two-phase zone, the area of the treated substrate surface, depending on the speed of its movement and induction heating characteristics were estimated.

Imatinib Mesylate in Treating Patients With Progressive, Refractory, or Recurrent Stage II or Stage III Testicular or Ovarian Cancer

ClinicalTrials.gov

2013-01-15

Ovarian Dysgerminoma; Recurrent Malignant Testicular Germ Cell Tumor; Recurrent Ovarian Germ Cell Tumor; Stage II Malignant Testicular Germ Cell Tumor; Stage II Ovarian Germ Cell Tumor; Stage III Malignant Testicular Germ Cell Tumor; Stage III Ovarian Germ Cell Tumor; Testicular Seminoma

Neuroblastoma pathogenesis: deregulation of embryonic neural crest development.

PubMed

Tomolonis, Julie A; Agarwal, Saurabh; Shohet, Jason M

2018-05-01

Neuroblastoma (NB) is an aggressive pediatric cancer that originates from neural crest tissues of the sympathetic nervous system. NB is highly heterogeneous both from a clinical and a molecular perspective. Clinically, this cancer represents a wide range of phenotypes ranging from spontaneous regression of 4S disease to unremitting treatment-refractory progression and death of high-risk metastatic disease. At a cellular level, the heterogeneous behavior of NB likely arises from an arrest and deregulation of normal neural crest development. In the present review, we summarize our current knowledge of neural crest development as it relates to pathways promoting 'stemness' and how deregulation may contribute to the development of tumor-initiating CSCs. There is an emerging consensus that such tumor subpopulations contribute to the evolution of drug resistance, metastasis and relapse in other equally aggressive malignancies. As relapsed, refractory disease remains the primary cause of death for neuroblastoma, the identification and targeting of CSCs or other primary drivers of tumor progression remains a critical, clinically significant goal for neuroblastoma. We will critically review recent and past evidence in the literature supporting the concept of CSCs as drivers of neuroblastoma pathogenesis.

High-dose ifosfamide by infusion with Mesna in advanced refractory sarcomas.

PubMed

Güllü, I; Yalçin, S; Tekuzman, G; Barişta, I; Alkiş, N; Celik, I; Zengin, N; Güler, N; Kars, A; Baltali, E

1996-01-01

Twenty patients with advanced sarcomas entered a pilot study with ifosfamide (IF) and mercaptoethane sulfonate sodium (Mesna) as a second-line treatment for six planned cycles. All patients had received prior doxorubicin- and cyclophosphamide-based chemotherapies. IF was administered at a dose of 3 g/m2 given as continuous intravenous infusion for 24 hr on day 1-5 with Mesna. In the absence of disease progression, chemotherapy was planned to be repeated every 4 weeks for six consecutive cycles. Following chemotherapy, only 2 patients (11%) achieved partial response with response durations of 6 and 9 months. There was no complete response. When considered for only high-grade tumors, the response rate reached up to 22%. Toxicity was reported for 48 cycles and the dose-limiting toxicities were myelosuppression (22%) and encephalopathy (17%). Chemotherapy protocol was changed after two or three courses in 16 patients with stable or progressive disease. IF/Mesna chemotherapy at this dose and schedule was not found to be very promising in refractory sarcomas as a second-line chemotherapy.

Chondritic Meteorites: Nebular and Parent-Body Formation Processes

NASA Technical Reports Server (NTRS)

Rubin, Alan E.; Lindstrom, David (Technical Monitor)

2002-01-01

It is important to identify features in chondrites that formed as a result of parent-body modification in order to disentangle nebular and asteroidal processes. However, this task is difficult because unmetamorphosed chondritic meteorites are mixtures of diverse components including various types of chondrules, chondrule fragments, refractory and mafic inclusions, metal-sulfide grains and fine-grained matrix material. Shocked chondrites can contain melt pockets, silicate-darkened material, metal veins, silicate melt veins, and impact-melt-rock clasts. This grant paid for several studies that went far in helping to distinguish primitive nebular features from those produced during asteroidal modification processes.

Feasibility of producing cast-refractory metal-fiber superalloy composites

NASA Technical Reports Server (NTRS)

Mcintyre, R. D.

1973-01-01

A study was conducted to evaluate the feasibility of direct casting as a practical method for producing cast superalloy tungsten or columbium alloy fiber composites while retaining a high percentage of fiber strength. Fourteen nickel base, four cobalt, and three iron based matrices were surveyed for their degree of reaction with the metal fibers. Some stress-rupture results were obtained at temperatures of 760, 816, 871, and 1093 C for a few composite systems. The feasibility of producing acceptable composites of some cast nickel, cobalt, and iron matrix alloys with tungsten or columbium alloy fibers was demonstrated.

Inertial Weldment of Rhenium and Inconel 718

NASA Technical Reports Server (NTRS)

Cavender, D. P.; Courtright, Z. S.; Hostetter, G.; Laiman, M.

2018-01-01

Inertia welding has been found to be a successful method for joining pure rhenium to Inconel 718, and with additional experimentation, this process may have great potential for rocket nozzle applications. Refractory metals are ideally suited to this application, where high temperatures and oxidizing environment survivability is required, but not all of the thruster must be made of these materials, only the areas that require them. A bolted joint between the two metals is not ideal, especially for small thrusters where the mess of a bolted join will come at a steep price. A welded joint would be preferred for flight thrusters.

Materials technology programs in support of a mercury Rankine space power system

NASA Technical Reports Server (NTRS)

Stone, P. L.

1973-01-01

A large portion of the materials technology is summarized that was generated in support of the development of a mercury-rankine space power system (SNAP-8). The primary areas of investigation are: (1) the compatibility of various construction materials with the liquid metals mercury and NaK, (2) the mechanical properties of unalloyed tantalum, and (3) the development of refractory metal/austenitic stainless steel tubing and transition joints. The primary results, conclusions, and state of technology at the completion of this effort for each of these areas are summarized. Results of possible significance to other applications are highlighted.

Magnetron-Sputtered Amorphous Metallic Coatings

NASA Technical Reports Server (NTRS)

Thakoor, A. P.; Mehra, M.; Khanna, S. K.

1985-01-01

Amorphous coatings of refractory metal/metalloid-based alloys deposited by magnetron sputtering provide extraordinary hardness and wear resistance. Sputtering target fabricated by thoroughly mixing powders of tungsten, rhenium, and boron in stated proportions and pressing at 1,200 degrees C and 3,000 lb/in. to second power (21 MPa). Substrate lightly etched by sputtering before deposition, then maintained at bias of - 500 V during initial stages of film growth while target material sputtered onto it. Argon gas at pressure used as carrier gas for sputter deposition. Coatings dense, pinhole-free, extremely smooth, and significantly resistant to chemical corrosion in acidic and neutral aqueous environments.

Series II AMTEC cell development issues

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sievers, R.K.; Rasmussen, J.R.; Giglio, J.C.

1998-07-01

The Series II alkali metal thermal to electric converter (AMTEC) cell, developed over the last two year, represents a significant engineering advance in AMTEC technology, and major step toward spacecraft power systems. The PX-5 cell design was developed as an early prototype in stainless steel alloys. This design will evolve into the PX-6 engineering cell and finally into the EPX-1 to be used in the Advanced Radioisotope Power System (ARPS) program. The EPX-1 cell will be all-refractory metal. Late work on the PX-5 and early work on the PX-6 will be described.

Low resistance contacts for shallow junction semiconductors

NASA Technical Reports Server (NTRS)

Fatemi, Navid S. (Inventor); Weizer, Victor G. (Inventor)

1994-01-01

A method of enhancing the specific contact resistivity in InP semiconductor devices and improved devices produced thereby are disclosed. Low resistivity values are obtained by using gold ohmic contacts that contain small amounts of gallium or indium and by depositing a thin gold phosphide interlayer between the surface of the InP device and the ohmic contact. When both the thin interlayer and the gold-gallium or gold-indium contact metallizations are used, ultra low specific contact resistivities are achieved. Thermal stability with good contact resistivity is achieved by depositing a layer of refractory metal over the gold phosphide interlayer.

Innovation processes in technologies for the processing of refractory mineral raw materials

NASA Astrophysics Data System (ADS)

Chanturiya, V. A.

2008-12-01

Analysis of the grade of mineral resources of Russia and other countries shows that end products that are competitive in terms of both technological and environmental criteria in the world market can only be obtained by the development and implementation of progressive technologies based on the up-to-date achievements of fundamental sciences. The essence of modern innovation processes in technologies developed in Russia for the complex and comprehensive processing of refractory raw materials with a complex composition is ascertained. These processes include (i) radiometric methods of concentration of valuable components, (ii) high-energy methods of disintegration of highly dispersed mineral components, and (iii) electrochemical methods of water conditioning to obtain target products for solving specific technological problems.

Development and Implementation of Nationally Recognized Laboratory for Material Characterization in the Microwave and Millimeter Wave Bands

NASA Technical Reports Server (NTRS)

Hepburn, Frank L.; Russell, Samuel S.

2010-01-01

This report provides a progress update for establishing a laboratory for material characterization in the microwave and millimeter wave bands. During the launch of STS-124 a large area of refractory bricks was liberated from the flame trench built for the exhaust of the solid rocket motors (SRM). The inspection of the liberated area revealed many defects, debonds, corrosion and voids that are a cause for concern relating to the health of the entire flame trench wall. A request for assistance was received for the nondestructive evaluation (NDE) of these anomalies behind the refractory bricks, with the primary interest being a health assessment based on the quality of the brick, epoxy and concrete bond.

Poor prognosis in non-villous splenic marginal zone cell lymphoma is associated with p53 mutations.

PubMed

Baldini, L; Guffanti, A; Cro, L; Fracchiolla, N S; Colombi, M; Motta, M; Maiolo, A T; Neri, A

1997-11-01

We have recently reported a series of 15 non-villous splenic marginal zone lymphoma patients, six of whom showed p53 mutations (40%). This molecular alteration did not correlate with any particular clinico-pathologic feature at diagnosis. After a median follow-up of 56 months, four cases evolved into aggressive fatal non-Hodgkin's lymphoma (NHL) and two had refractory progressive disease; interestingly, p53 mutations were demonstrated in five of these patients at diagnosis. As the patients with wild-type p53 presented responsive or indolent disease, this genetic alteration may be an early marker of aggressive transformation or refractoriness. p53 evaluation at diagnosis could be advisable in this particular subset of NHL.

Long-term response to combination therapy with estramustine and somatostatin analogue in a patient with androgen ablation-refractory prostate cancer.

PubMed

Cerulli, Costantino; Sciarra, Alessandro; Salvatori, Gianfilippo; Di Silverio, Franco

2004-12-01

We report on a patient with androgen ablation-refractory prostate adenocarcinoma who had an objective response for longer than 24 months using a combination of estramustine and lanreotide. At baseline from our combination therapy, his prostate-specific antigen level was 21.30 ng/mL and serum chromogranin A level was 816 ng/mL. The patient discontinued complete androgen deprivation therapy and underwent combination therapy with oral estramustine 420 mg/day plus lanreotide acetate 73.9 mg intramuscularly every 4 weeks. After 33 months of follow-up, the patient was alive without clinical disease progression, and his prostate-specific antigen and chromogranin A level was 0.10 and 12 ng/mL, respectively.

Dynamic oxidation behavior at 1000 and 1100 C of four nickel-base cast alloys, NASA-TRW VIA, B-1900, 713C, and 738X

NASA Technical Reports Server (NTRS)

Sanders, W. A.

1974-01-01

The superalloys NASA-TRW VIA, B-1900, 713C, and 738X were tested cyclically and isothermally for resistance to oxidation in high velocity gas streams for 100 hours at specimen temperatures of 1000 C and 1100 C. Alloys VIA and B-1900, which were the most oxidation resistant, displayed slight and very similar weight changes and metal losses. Alloy 713C also sustained only slight metal losses, but it exhibited some tendency to spall. Alloy 738X was found to be the most susceptible to cyclic oxidation; this resulted in heavy spalling, which in turn caused high weight losses and high metal losses. Oxidation test results are related to the amounts of chromium aluminum, and the refractory metals in the alloys investigated.

Axitinib treatment in advanced RAI-resistant differentiated thyroid cancer (DTC) and refractory medullary thyroid cancer (MTC).

PubMed

Capdevila, Jaume; Trigo, José Manuel; Aller, Javier; Manzano, José Luís; Adrián, Silvia García; Llopis, Carles Zafón; Reig, Òscar; Bohn, Uriel; Cajal, Teresa Ramón Y; Duran-Poveda, Manuel; Astorga, Beatriz González; López-Alfonso, Ana; Martínez, Javier Medina; Porras, Ignacio; Reina, Juan Jose; Palacios, Nuria; Grande, Enrique; Cillán, Elena; Matos, Ignacio; Grau, Juan Jose

2017-10-01

Axitinib, an antiangiogenic multikinase inhibitor (MKI), was evaluated in the compassionate use programme (CUP) in Spain (October 2012-November 2014). 47 patients with advanced radioactive iodine (RAI)-refractory differentiated thyroid cancer (DTC, n  = 34) or medullary thyroid cancer (MTC, n  = 13) with documented disease progression were treated with axitinib 5 mg b.i.d. The primary efficacy endpoint was objective response rate (ORR) by Response Evaluation Criteria In Solid Tumors (RECIST) v1.1. Progression-free survival (PFS) and adverse events (AEs) were secondary objectives. Regulatory authorities validated the CUP, and all patients signed informed consent form. Axitinib was administered as first-line therapy in 17 patients (36.2%), as second-line in 18 patients (38.3%) and as third/fourth-line in 12 patients (25.5%). With a median follow-up of 11.5 months (0-24.3), ORR was 27.7% (DTC: 29.4% and MTC: 23.1%) and median PFS was 8.1 months (95% CI: 4.1-12.2) (DTC: 7.4 months (95% CI: 3.1-11.8) and MTC: 9.4 months (95% CI: 4.8-13.9)). Better outcomes were reported with first-line axitinib, with an ORR of 53% and a median PFS of 13.6 months compared with 16.7% and 10.6 months as second-line treatment. Twelve (25.5%) patients required dose reduction to 3 mg b.i.d. All-grade AEs included asthenia (53.2%), diarrhoea (36.2%), hypertension (31.9%) and mucositis (29.8%); grade 3/4 AEs included anorexia (6.4%), diarrhoea (4.3%) and cardiac toxicity (4.3%). Axitinib had a tolerable safety profile and clinically meaningful activity in refractory and progressive thyroid cancer regardless of histology as first-line therapy. To our knowledge, this is the first time that cross-resistance between MKIs is suggested in thyroid cancer, highlighting the importance of prospective sequential clinical studies. © 2017 European Society of Endocrinology.

Extracorporeal cytokine elimination as rescue therapy in refractory septic shock: a prospective single-center study.

PubMed

Friesecke, Sigrun; Stecher, Stephanie-Susanne; Gross, Stefan; Felix, Stephan B; Nierhaus, Axel

2017-09-01

Sepsis is the most common cause of death in medical intensive care units (ICU). If sepsis progresses to refractory septic shock, mortality may reach 90-100% despite optimum current therapy. Extracorporeal cytokine adsorption in addition to regular therapy was studied prospectively in refractory septic shock patients on a medical ICU. Refractory shock was defined as increasing vasopressor dose required to maintain mean arterial blood pressure above 65 mmHg or increasing lactate levels despite protocol-guided shock therapy for 6 h. We analysed noradrenaline requirements after 6 and 12 h (primary endpoint), lactate clearance after 6 and 12 h, SOFA-scores in the first days and achievement of shock reversal (i.e., normalization of lactate concentrations and sustained discontinuation of vasopressors; secondary endpoints). Twenty consecutive patients with refractory septic shock were included; CytoSorb ® treatment was started after 7.8 ± 3.7 h of shock therapy. Following the initiation of adsorption therapy, noradrenaline dose could be significantly reduced after 6 (-0.4 µg/kg/min; p = 0.03) and 12 h (-0.6 µg/kg/min; p = 0.001). Lactate clearance improved significantly. SOFA-scores on day 0, 1 and 2 remained unchanged. Shock reversal was achieved in 13 (65%) patients; 28-day survival was 45%. In severe septic shock unresponsive to standard treatment, haemodynamic stabilization was achieved using cytokine adsorption therapy, resulting in shock reversal in two-thirds of these patients. The study was registered in the German Register for Clinical Trials (DRKS) No. 00005149.

40 CFR 471.54 - Pretreatment standards for existing sources (PSES).

Code of Federal Regulations, 2010 CFR

2010-07-01

... 12.1 Nickel 23.3 15.4 Fluoride 720 320 Molybdenum 80.0 41.4 (n) Alkaline cleaning spent baths... (pounds per million off-pounds) of refractory metals alkaline cleaned Copper 0.635 0.334 Nickel 0.642 0.424 Fluoride 19.9 8.82 Molybdenum 2.21 1.14 (o) Alkaline cleaning rinse. Subpart E—PSES Pollutant or...

40 CFR 471.54 - Pretreatment standards for existing sources (PSES).

Code of Federal Regulations, 2011 CFR

2011-07-01

... 12.1 Nickel 23.3 15.4 Fluoride 720 320 Molybdenum 80.0 41.4 (n) Alkaline cleaning spent baths... (pounds per million off-pounds) of refractory metals alkaline cleaned Copper 0.635 0.334 Nickel 0.642 0.424 Fluoride 19.9 8.82 Molybdenum 2.21 1.14 (o) Alkaline cleaning rinse. Subpart E—PSES Pollutant or...

40 CFR 471.54 - Pretreatment standards for existing sources (PSES).

Code of Federal Regulations, 2012 CFR

2012-07-01

... 12.1 Nickel 23.3 15.4 Fluoride 720 320 Molybdenum 80.0 41.4 (n) Alkaline cleaning spent baths... (pounds per million off-pounds) of refractory metals alkaline cleaned Copper 0.635 0.334 Nickel 0.642 0.424 Fluoride 19.9 8.82 Molybdenum 2.21 1.14 (o) Alkaline cleaning rinse. Subpart E—PSES Pollutant or...

40 CFR 471.55 - Pretreatment standards for new sources (PSNS).

Code of Federal Regulations, 2014 CFR

2014-07-01

... surface treated Copper 15.5 7.38 Nickel 6.66 4.48 Fluoride 720 320 Molybdenum 60.9 27.0 (n) Alkaline... monthly average mg/off-kg (pounds per million off-pounds) of refractory metals alkaline cleaned Copper 0.428 0.204 Nickel 0.184 0.124 Fluoride 19.9 8.82 Molybdenum 1.68 0.745 (o) Alkaline cleaning rinse...

40 CFR 471.55 - Pretreatment standards for new sources (PSNS).

Code of Federal Regulations, 2011 CFR

2011-07-01

... surface treated Copper 15.5 7.38 Nickel 6.66 4.48 Fluoride 720 320 Molybdenum 60.9 27.0 (n) Alkaline... monthly average mg/off-kg (pounds per million off-pounds) of refractory metals alkaline cleaned Copper 0.428 0.204 Nickel 0.184 0.124 Fluoride 19.9 8.82 Molybdenum 1.68 0.745 (o) Alkaline cleaning rinse...

40 CFR 471.55 - Pretreatment standards for new sources (PSNS).

Code of Federal Regulations, 2010 CFR

2010-07-01

... surface treated Copper 15.5 7.38 Nickel 6.66 4.48 Fluoride 720 320 Molybdenum 60.9 27.0 (n) Alkaline... monthly average mg/off-kg (pounds per million off-pounds) of refractory metals alkaline cleaned Copper 0.428 0.204 Nickel 0.184 0.124 Fluoride 19.9 8.82 Molybdenum 1.68 0.745 (o) Alkaline cleaning rinse...

40 CFR 471.54 - Pretreatment standards for existing sources (PSES).

Code of Federal Regulations, 2013 CFR

2013-07-01

... 12.1 Nickel 23.3 15.4 Fluoride 720 320 Molybdenum 80.0 41.4 (n) Alkaline cleaning spent baths... (pounds per million off-pounds) of refractory metals alkaline cleaned Copper 0.635 0.334 Nickel 0.642 0.424 Fluoride 19.9 8.82 Molybdenum 2.21 1.14 (o) Alkaline cleaning rinse. Subpart E—PSES Pollutant or...

40 CFR 471.55 - Pretreatment standards for new sources (PSNS).

Code of Federal Regulations, 2012 CFR

2012-07-01

... surface treated Copper 15.5 7.38 Nickel 6.66 4.48 Fluoride 720 320 Molybdenum 60.9 27.0 (n) Alkaline... monthly average mg/off-kg (pounds per million off-pounds) of refractory metals alkaline cleaned Copper 0.428 0.204 Nickel 0.184 0.124 Fluoride 19.9 8.82 Molybdenum 1.68 0.745 (o) Alkaline cleaning rinse...

40 CFR 471.55 - Pretreatment standards for new sources (PSNS).

Code of Federal Regulations, 2013 CFR

2013-07-01

... surface treated Copper 15.5 7.38 Nickel 6.66 4.48 Fluoride 720 320 Molybdenum 60.9 27.0 (n) Alkaline... monthly average mg/off-kg (pounds per million off-pounds) of refractory metals alkaline cleaned Copper 0.428 0.204 Nickel 0.184 0.124 Fluoride 19.9 8.82 Molybdenum 1.68 0.745 (o) Alkaline cleaning rinse...

40 CFR 471.54 - Pretreatment standards for existing sources (PSES).

Code of Federal Regulations, 2014 CFR

2014-07-01

... 12.1 Nickel 23.3 15.4 Fluoride 720 320 Molybdenum 80.0 41.4 (n) Alkaline cleaning spent baths... (pounds per million off-pounds) of refractory metals alkaline cleaned Copper 0.635 0.334 Nickel 0.642 0.424 Fluoride 19.9 8.82 Molybdenum 2.21 1.14 (o) Alkaline cleaning rinse. Subpart E—PSES Pollutant or...

Gas Atomization Equipment Statement of Work and Specification for Engineering design, Fabrication, Testing, and Installation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boutaleb, T.; Pluschkell, T. P.

The Gas Atomization Equipment will be used to fabricate metallic powder suitable for Powder Bed Fusion additive Manufacturing material to support Lawrence Livermore National Laboratory (LLNL) research and development. The project will modernize our capabilities to develop spherical reactive, refractory, and radioactive powders in the 10-75 μm diameter size range at LLNL.

Studies of Silicon Refractory Metal Interfaces: Photoemission Study of Interface Formation and Compound Nucleation.

DTIC Science & Technology

1983-09-08

1982). 4. A. Hiraki , M.-A. Nicolet, and J.W. Mayer, Appl. Phys. Lett. 18, 178 (1971); A. Hiraki , K. Shuto, S. Kim, W. Kammura, and M. twami, ibid 31...Vac. Sci. Technol. 17, 930 (1980) and references therein. 13 T. Narusera, K. Kinoehica, W. 1. Gibson, and A. Hiraki , J. Vac. Sci. Technol. L$, 272

Evaporation Source for Deposition of Protective Layers inside Tubes

NASA Astrophysics Data System (ADS)

Musa, Geavit; Mustata, Ion; Dinescu, Gheorghe; Bajeu, George; Raiciu, Elena

1992-09-01

A heated cathode arc can be ignited in vacuum in the vapours of the anode material due to the accelerated electron beam from the cathode. A small assembly, consisting of an electron gun as the cathode and a refractory metal crucible, containing the material to be evaporated, as the anode, can be moved along the axis of the tube whose inside wall is to be covered with a protective layer. The vacuum arc ignited between the electrodes in the vapours of the evaporating anode material ensures a high deposition rate with low thermal energy transport to the tube wall. This new method can be used for the deposition of various metal layers inside different kinds of tubes (metallic, glass, ceramics or plastics).

Atomic and electronic basis for the serrations of refractory high-entropy alloys

NASA Astrophysics Data System (ADS)

Wang, William Yi; Shang, Shun Li; Wang, Yi; Han, Fengbo; Darling, Kristopher A.; Wu, Yidong; Xie, Xie; Senkov, Oleg N.; Li, Jinshan; Hui, Xi Dong; Dahmen, Karin A.; Liaw, Peter K.; Kecskes, Laszlo J.; Liu, Zi-Kui

2017-06-01

Refractory high-entropy alloys present attractive mechanical properties, i.e., high yield strength and fracture toughness, making them potential candidates for structural applications. Understandings of atomic and electronic interactions are important to reveal the origins for the formation of high-entropy alloys and their structure-dominated mechanical properties, thus enabling the development of a predictive approach for rapidly designing advanced materials. Here, we report the atomic and electronic basis for the valence-electron-concentration-categorized principles and the observed serration behavior in high-entropy alloys and high-entropy metallic glass, including MoNbTaW, MoNbVW, MoTaVW, HfNbTiZr, and Vitreloy-1 MG (Zr41Ti14Cu12.5Ni10Be22.5). We find that the yield strengths of high-entropy alloys and high-entropy metallic glass are a power-law function of the electron-work function, which is dominated by local atomic arrangements. Further, a reliance on the bonding-charge density provides a groundbreaking insight into the nature of loosely bonded spots in materials. The presence of strongly bonded clusters and weakly bonded glue atoms imply a serrated deformation of high-entropy alloys, resulting in intermittent avalanches of defects movement.

Brazed graphite/refractory metal composites for first-wall protection elements

NASA Astrophysics Data System (ADS)

Šmid, I.; Croessmann, C. D.; Salmonson, J. C.; Whitley, J. B.; Kny, E.; Reheis, N.; Kneringer, G.; Nickel, H.

1991-03-01

The peak surface heat flux deposition on divertor elements of near term fusion devices is expected to exceed 10 MW/m 2. The needed reliability of brazed plasma interactive components, particularly under abnormal operating conditions with peak surface temperatures well beyond 1000°C, makes refractory metallic substrates and brazes with a high melting point very attractive. TZM, a high temperature alloy of molybdenum, and isotropic graphite, materials very closely matched in their thermal expansion, were brazed with four high-temperature brazes. The brazes used were Zr, 90Ni/10Ti, 90Cu/10Ti and 70Ag/27Cu/3Ti (nominal composition prior to brazing, wt%). The resulting composite tiles of 50 × 50 mm2 with a TZM thickness of 5 mm and a graphite thickness of 10 mm have been tested in high heat flux simulation for their thermal fatigue properties. Up to 600 loading cycles were carried out with an average heat flux of 10 MW/m 2 for 0.5 s pulses. The maximum surface temperature was 1100°C. In support of the experiment, the thermal response and temperature gradients of the samples were investigated using a finite element model.

Emerging Role of Immunotherapy in Advanced Urothelial Carcinoma.

PubMed

Koshkin, Vadim S; Grivas, Petros

2018-04-11

Advanced urothelial carcinoma (aUC) has long been treated preferably with cisplatin-based chemotherapy, but many patients are cisplatin-ineligible whereas for those who progress on a platinum-based regimen treatment options are limited. We review key recent data regarding immune checkpoint inhibitors that are changing this treatment landscape. Since May 2016, five different agents targeting the PD-1/PD-L1 pathway (atezolizumab, pembrolizumab, nivolumab, avelumab, durvalumab) have received FDA approval for the treatment of aUC in the platinum-refractory setting, while pembrolizumab and atezolizumab are FDA-approved for cisplatin-ineligible patients in the first-line setting. Clinical outcomes and safety profiles of these agents appear relatively comparable across separate trials; however, only pembrolizumab is supported by level I evidence from a large randomized phase III trial showing overall survival benefit over conventional cytotoxic salvage chemotherapy in the platinum-refractory setting. Pembrolizumab has the highest level of evidence in platinum-refractory aUC, whereas pembrolizumab and atezolizumab have comparable level of evidence in the frontline setting in cisplatin-ineligible patients. Ongoing research is evaluating novel agents, various rational combinations, and sequences, as well as predictive and prognostic biomarkers.

Alemtuzumab as treatment of steroid-refractory acute graft-versus-host disease: results of a phase II study.

PubMed

Martínez, Carmen; Solano, Carlos; Ferrá, Christelle; Sampol, Antonia; Valcárcel, David; Pérez-Simón, José Antonio

2009-05-01

We conducted a phase II trial to investigate the safety and efficacy of alemtuzumab in treating steroid-refractory acute graft-versus-host disease (aGVHD) grade II or higher after stem cell transplantation. Ten adult patients (6 with aGVHD grade III and 4 with aGVHD grade IV) were included in the study. Nine patients had gastrointestinal tract involvement, 7 had skin involvement, and 5 had liver involvement. Five patients responded to treatment, 2 with complete response and 3 with partial response. Eight infectious events (4 of grade 3-4) and 7 cytomegalovirus (CMV) reactivations were observed. Six patients had grade 3-4 cytopenia. All 10 patients died (7 resulting from aGVHD progression, 2 from severe infection, and 1 from to leukemia relapse), at a median of 40 days (range, 4 to 88 days) after alemtuzumab treatment. Overall, our findings suggest that steroid-refractory aGVHD may be improved by treatment with alemtuzumab, but that this treatment does not overcome the dismal prognosis of patients with severe aGVHD, demonstrating the need for alternative therapies to treat this complication.

Successful treatment of generalized refractory chronic periodontitis through discontinuation of waxed or coated dental floss use: A report of 4 cases.

PubMed

Kelekis-Cholakis, Anastasia; Perry, John B; Pfeffer, Lorraine; Millete, Amy

2016-12-01

Generalized refractory chronic periodontitis is a periodontal condition that is resistant to conventional therapy. Management of this condition often is frustrating to both the patient and the clinician. The authors present 4 cases of generalized refractory chronic periodontitis characterized by an inflammatory gingival response and progressive bone loss that did not respond to extensive periodontal treatments and regular periodontal care. Histologic examination of affected gingival tissue revealed an abundance of plasma cells, a feature seen in certain oral contact hypersensitivity reactions. The authors suspected that waxed or coated dental floss was the offending contactant, and its removal from the patients' oral hygiene regimens resulted in a dramatic improvement of the periodontal characteristics. In cases of periodontal disease as described in this report, dental practitioners should consider the possibility of a contact hypersensitivity reaction to waxed or coated dental floss, whereby the floss exacerbates the condition instead of assisting in its resolution. Copyright © 2016 American Dental Association. Published by Elsevier Inc. All rights reserved.

Silibinin suppresses EMT-driven erlotinib resistance by reversing the high miR-21/low miR-200c signature in vivo

PubMed Central

Cufí, Sílvia; Bonavia, Rosa; Vazquez-Martin, Alejandro; Oliveras-Ferraros, Cristina; Corominas-Faja, Bruna; Cuyàs, Elisabet; Martin-Castillo, Begoña; Barrajón-Catalán, Enrique; Visa, Joana; Segura-Carretero, Antonio; Joven, Jorge; Bosch-Barrera, Joaquim; Micol, Vicente; Menendez, Javier A.

2013-01-01

The flavolignan silibinin was studied for its ability to restore drug sensitivity to EGFR-mutant NSCLC xenografts with epithelial-to-mesenchymal transition (EMT)-driven resistance to erlotinib. As a single agent, silibinin significantly decreased the tumor volumes of erlotinib-refractory NSCLC xenografts by approximately 50%. Furthermore, the complete abrogation of tumor growth was observed with the co-treatment of erlotinib and silibinin. Silibinin fully reversed the EMT-related high miR-21/low miR-200c microRNA signature and repressed the mesenchymal markers SNAIL, ZEB, and N-cadherin observed in erlotinib-refractory tumors. Silibinin was sufficient to fully activate a reciprocal mesenchymal-to-epithelial transition (MET) in erlotinib-refractory cells and prevent the highly migratogenic phenotype of erlotinib-resistant NSCLC cells. Given that the various mechanisms of resistance to erlotinib result from EMT, regardless of the EGFR mutation status, a water-soluble, silibinin-rich milk thistle extract might be a suitable candidate therapy for upcoming clinical trials aimed at preventing or reversing NSCLC progression following erlotinib treatment. PMID:23963283

Brentuximab vedotin in refractory CD30+ lymphomas: a bridge to allogeneic transplantation in approximately one quarter of patients treated on a Named Patient Programme at a single UK center

PubMed Central

Gibb, Adam; Jones, Craig; Bloor, Adrian; Kulkarni, Samar; Illidge, Tim; Linton, Kim; Radford, John

2013-01-01

The CD30-targeted agent brentuximab vedotin has shown impressive activity in relapsed/refractory Hodgkin lymphoma and anaplastic large cell lymphoma in phase II studies. We have treated 24 patients with relapsed/refratory disease enrolled onto a Named Patient Programme during 2010-11 at a single UK center. Overall response rate across all histologies was 67% (Hodgkin 72%; anaplastic large cell 60%), complete response rate 25% (Hodgkin 17%; anaplastic large cell 60%), median progression-free survival 5.1 months, and toxicity mild to moderate in the majority of cases. Six patients proceeded to allogeneic transplantation and one patient awaits this procedure. These results are similar to phase II data and show that brentuximab vedotin provides a bridge to allogeneic transplantation in approximately one quarter of patients refractory to conventional salvage therapies. Best response was seen after four doses, so consideration of allogeneic transplantation should be made early and scheduled following the first assessment indicating response. PMID:23065511

A phase 1 study of the PI3Kδ inhibitor idelalisib in patients with relapsed/refractory mantle cell lymphoma (MCL)

PubMed Central

Spurgeon, Stephen E.; Furman, Richard R.; Flinn, Ian W.; Coutre, Steven E.; Brown, Jennifer R.; Benson, Don M.; Byrd, John C.; Peterman, Sissy; Cho, Yoonjin; Yu, Albert; Godfrey, Wayne R.; Wagner-Johnston, Nina D.

2014-01-01

Idelalisib, an oral inhibitor of phosphatidylinositol-3-kinase δ (PI3Kδ), was evaluated in a 48-week phase 1 study (50-350 mg daily or twice daily) enrolling 40 patients with relapsed or refractory mantle cell lymphoma (MCL). Primary outcome was safety and dose-limiting toxicity (DLT). Secondary outcomes were pharmacokinetic parameters, pharmacodynamic effects, overall response rate (ORR), progression-free survival (PFS), and duration of response (DOR). Patients without DLT and no evidence of disease progression after 48 weeks enrolled in the extension study. Patients had median age of 69 years (range, 52-83) and received median of 4 prior therapies (1-14); 17 of 40 patients (43%) were refractory to their most recent treatment. Median duration of idelalisib treatment was 3.5 months (range, 0.7-30.7), with 6 (15%) continuing extension treatment. Common grade ≥3 adverse events (AEs) included (total%/grade ≥3%) diarrhea (40/18), nausea (33/5), pyrexia (28/0), fatigue (25/3), rash (23/3), decreased appetite (20/15), upper respiratory infection (20/0), pneumonia (13/10), and alanine transaminase or aspartate transaminase elevations (60/20). ORR was 16 of 40 patients (40%), with CR in 2 of 40 patients (5%). Median DOR was 2.7 months, median PFS was 3.7 months, and 1-year PFS was 22%. These data provide proof of concept that targeting PI3Kδ is a viable strategy and worthy of additional study in MCL. This trial was registered at www.clinicaltrials.gov as #NCT00710528. PMID:24615778

Survey of Materials for Fusion Fission Hybrid Reactors Vol 1 Rev. 0

DOE Office of Scientific and Technical Information (OSTI.GOV)

Farmer, Joseph Collin

2007-07-03

Materials for fusion-fission hybrid reactors fall into several broad categories, including fuels, blanket and coolant materials, cladding, structural materials, shielding, and in the specific case of inertial-confinement fusion systems, laser and optical materials. This report surveys materials in all categories of materials except for those required for lasers and optics. Preferred collants include two molten salt mixtures known as FLIBE (Li2BeF4) and FLINABE (LiNaBeF4). In the case of homogenous liquid fuels, UF4 can be dissolved in these molten salt mixtures. The transmutation of lithium in this coolant produces very corrosive hydrofluoric acid species (HF and TF), which can rapidly degrademore » structural materials. Broad ranges of high-melting radiation-tolerant structural material have been proposed for fusion-fission reactor structures. These include a wide variety of steels and refractory alloys. Ferritic steels with oxide-dispersion strengthening and graphite have been given particular attention. Refractory metals are found in Groups IVB and VB of the periodic table, and include Nb, Ta, Cr, Mo, and W, as serve as the basis of refractory alloys. Stable high-melting composites and amorphous metals may also be useful. Since amorphous metals have no lattice structure, neutron bombardment cannot dislodge atoms from lattice sites, and the materials would be immune from this specific mode of degradation. The free energy of formation of fluorides of the alloying elements found in steels and refractory alloys can be used to determine the relative stability of these materials in molten salts. The reduction of lithium transmutation products (H + and T +) drives the electrochemical corrosion process, and liberates aggressive fluoride ions that pair with ions formed from dissolved structural materials. Corrosion can be suppressed through the use of metallic Be and Li, though the molten salt becomes laden with colloidal suspensions of Be and Li corrosion products in the process. Alternatively, imposed currents and other high-temperature cathodic protection systems are envisioned for protection of the structural materials. This novel concept could prove to be enabling technology for such high-temperature molten-salt reactors. The use of UF 4 as a liquid-phase homogenous fuel is also complicated by redox control. For example, the oxidation of tetravalent uranium to hexavalent uranium could result in the formation of volatile UF 6. This too could be controlled through electrochemically manipulated oxidation and reduction reactions. In situ studies of pertinent electrochemical reactions in the molten salts are proposed, and are relevant to both the corrosive attack of structural materials, as well as the volatilization of fuel. Some consideration is given to the potential advantages of gravity fed falling-film blankets. Such systems may be easier to control than vortex systems, but would require that cylindrical reaction vessels be oriented with the centerline normal to the gravitational field.« less

Fully covered self-expanding metal stents for refractory anastomotic colorectal strictures.

PubMed

Caruso, Angelo; Conigliaro, Rita; Manta, Raffaele; Manno, Mauro; Bertani, Helga; Barbera, Carmelo; Mirante, Vincenzo Giorgio; Frazzoni, Marzio

2015-05-01

Some patients with benign colorectal obstruction do not respond to endoscopic balloon dilation. Fully covered self-expandable metal stents (FCSEMSs) have several potential advantages over non-covered stents, including a higher likelihood of retrieval owing to limited local tissue reaction. However, the efficacy and safety of FCSEMSs in benign colorectal strictures have not yet been established. Retrospective analysis of prospectively collected data concerning patients with post-surgical benign symptomatic anastomotic colorectal strictures, refractory to endoscopic dilation and in whom FCSEMSs had been placed at our center. Technical success was defined as successful stent placement and deployment at the stricture site. Early clinical success was defined as symptom relief persisting at least for 3 days. Follow-up was based on monthly clinical evaluation and quarterly endoscopic assessment. Endoscopic stent removal was planned on the basis of clinical or endoscopic assessment. Prolonged clinical success was defined as persistent symptom relief during follow-up. Technical and early clinical success were obtained in 16 of 16 (100%) patients. The median follow-up was 21 months. Prolonged clinical success was achieved in 9/16 (56%) cases. There was no major complication, including perforation and bleeding. Stent migration occurred in 3 (19%) cases, in two of them associated with clinical failure. The median stent diameter was significantly higher in patients with successful than in those with unsuccessful clinical outcome (26 vs. 20 mm, P = 0.006). The clinical success rate was 1/6 (17%) in patients who received a 20-22 mm stent and 8/10 (80%) in those who received a 24-26 mm stent, respectively (P = 0.035). FCSEMSs can represent effective and safe treatment for refractory anastomotic colorectal strictures. Large diameter stents are warranted for better results.

Epsilon Metal Waste Form for Immobilization of Noble Metals from Used Nuclear Fuel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crum, Jarrod V.; Strachan, Denis M.; Rohatgi, Aashish

2013-10-01

Epsilon metal (ε-metal), an alloy of Mo, Pd, Rh, Ru, and Tc, is being developed as a waste form to treat and immobilize the undissolved solids and dissolved noble metals from aqueous reprocessing of commercial used nuclear fuel. Epsilon metal is an attractive waste form for several reasons: increased durability relative to borosilicate glass, it can be fabricated without additives (100% waste loading), and in addition it also benefits borosilicate glass waste loading by eliminating noble metals from the glass and thus the processing problems related there insolubility in glass. This work focused on the processing aspects of the epsilonmore » metal waste form development. Epsilon metal is comprised of refractory metals resulting in high reaction temperatures to form the alloy, expected to be 1500 - 2000°C making it a non-trivial phase to fabricate by traditional methods. Three commercially available advanced technologies were identified: spark-plasma sintering, microwave sintering, and hot isostatic pressing, and investigated as potential methods to fabricate this waste form. Results of these investigations are reported and compared in terms of bulk density, phase assemblage (X-ray diffraction and elemental analysis), and microstructure (scanning electron microscopy).« less

Epsilon metal waste form for immobilization of noble metals from used nuclear fuel

NASA Astrophysics Data System (ADS)

Crum, Jarrod V.; Strachan, Denis; Rohatgi, Aashish; Zumhoff, Mac

2013-10-01

Epsilon metal (ɛ-metal), an alloy of Mo, Pd, Rh, Ru, and Tc, is being developed as a waste form to treat and immobilize the undissolved solids and dissolved noble metals from aqueous reprocessing of commercial used nuclear fuel. Epsilon metal is an attractive waste form for several reasons: increased durability relative to borosilicate glass, it can be fabricated without additives (100% waste loading), and in addition it also benefits borosilicate glass waste loading by eliminating noble metals from the glass, thus the processing problems related to their insolubility in glass. This work focused on the processing aspects of the epsilon metal waste form development. Epsilon metal is comprised of refractory metals resulting in high alloying temperatures, expected to be 1500-2000 °C, making it a non-trivial phase to fabricate by traditional methods. Three commercially available advanced technologies were identified: spark-plasma sintering, microwave sintering, and hot isostatic pressing, and investigated as potential methods to fabricate this waste form. Results of these investigations are reported and compared in terms of bulk density, phase assemblage (X-ray diffraction and elemental analysis), and microstructure (scanning electron microscopy).

Nanoceramic -Metal Matrix Composites by In-Situ Pyrolysis of Organic Precursors in a Liquid Melt

NASA Astrophysics Data System (ADS)

Sudarshan; Surappa, M. K.; Ahn, Dongjoon; Raj, Rishi

2008-12-01

We show the feasibility of introducing a dispersion of a refractory ceramic phase into metals by stirring a powder of an organic polymer into a magnesium melt and having it convert into a ceramic within the melt by in-situ pyrolysis of the polymer. The pyrolysis is a highly reactive process, accompanied by the evolution of hydrogen, which disperses the ceramic phase into nanoscale constituents. In the present experiments, a polysilazane-based precursor, which is known to yield an amorphous ceramic constituted from silicon, carbon, and nitrogen, was used. Five weight percent of the precursor (which has a nominal ceramic yield of 75 to 85 wt pct) produced a twofold increase in the room-temperature yield strength and reduced the steady-state strain rate at 450 °C by one to two orders of magnitude, relative to pure magnesium. This polymer-based in-situ process (PIP) for processing metal-matrix composites (MMCs) is likely to have great generality, because many different kinds of organic precursors, for producing oxide, carbides, nitrides, and borides, are commercially available. Also, the process would permit the addition of large volume fractions of the ceramic, enabling the nanostructural design, and production of MMCs with a wide range of mechanical properties, meant especially for high-temperature applications. An important and noteworthy feature of the present process, which distinguishes it from other methods, is that all the constituents of the ceramic phase are built into the organic molecules of the precursor ( e.g., polysilazanes contain silicon, carbon, and nitrogen); therefore, a reaction between the polymer and the host metal is not required to produce the dispersion of the refractory phase.

Modelling of Equilibrium Between Mantle and Core: Refractory, Volatile, and Highly Siderophile Elements

NASA Technical Reports Server (NTRS)

Righter, K.; Danielson, L.; Pando, K.; Shofner, G.; Lee, C. -T.

2013-01-01

Siderophile elements have been used to constrain conditions of core formation and differentiation for the Earth, Mars and other differentiated bodies [1]. Recent models for the Earth have concluded that the mantle and core did not fully equilibrate and the siderophile element contents of the mantle can only be explained under conditions where the oxygen fugacity changes from low to high during accretion and the mantle and core do not fully equilibrate [2,3]. However these conclusions go against several physical and chemical constraints. First, calculations suggest that even with the composition of accreting material changing from reduced to oxidized over time, the fO2 defined by metal-silicate equilibrium does not change substantially, only by approximately 1 logfO2 unit [4]. An increase of more than 2 logfO2 units in mantle oxidation are required in models of [2,3]. Secondly, calculations also show that metallic impacting material will become deformed and sheared during accretion to a large body, such that it becomes emulsified to a fine scale that allows equilibrium at nearly all conditions except for possibly the length scale for giant impacts [5] (contrary to conclusions of [6]). Using new data for D(Mo) metal/silicate at high pressures, together with updated partitioning expressions for many other elements, we will show that metal-silicate equilibrium across a long span of Earth s accretion history may explain the concentrations of many siderophile elements in Earth's mantle. The modeling includes refractory elements Ni, Co, Mo, and W, as well as highly siderophile elements Au, Pd and Pt, and volatile elements Cd, In, Bi, Sb, Ge and As.

Electrophysiological determinants of hypokalaemia-induced arrhythmogenicity in the guinea-pig heart.

PubMed

Osadchii, O E; Olesen, S P

2009-12-01

Hypokalaemia is an independent risk factor contributing to arrhythmic death in cardiac patients. In the present study, we explored the mechanisms of hypokalaemia-induced tachyarrhythmias by measuring ventricular refractoriness, spatial repolarization gradients, and ventricular conduction time in isolated, perfused guinea-pig heart preparations. Epicardial and endocardial monophasic action potentials from distinct left ventricular (LV) and right ventricular (RV) recording sites were monitored simultaneously with volume-conducted electrocardiogram (ECG) during steady-state pacing and following a premature extrastimulus application at progressively reducing coupling stimulation intervals in normokalaemic and hypokalaemic conditions. Hypokalaemic perfusion (2.5 mm K(+) for 30 min) markedly increased the inducibility of tachyarrhythmias by programmed ventricular stimulation and rapid pacing, prolonged ventricular repolarization and shortened LV epicardial and endocardial effective refractory periods, thereby increasing the critical interval for LV re-excitation. Hypokalaemia increased the RV-to-LV transepicardial repolarization gradients but had no effect on transmural dispersion of APD(90) and refractoriness across the LV wall. As determined by local activation time recordings, the LV-to-RV transepicardial conduction and the LV transmural (epicardial-to-endocardial) conduction were slowed in hypokalaemic heart preparations. This change was attributed to depressed diastolic excitability as evidenced by increased ventricular pacing thresholds. These findings suggest that hypokalaemia-induced arrhythmogenicity is attributed to shortened LV refractoriness, increased critical intervals for LV re-excitation, amplified RV-to-LV transepicardial repolarization gradients and slowed ventricular conduction in the guinea-pig heart.

Risk-adapted, treosulfan-based therapy with auto- and allo-SCT for relapsed/refractory aggressive NHL: a prospective phase-II trial.

PubMed

Koenigsmann, M; Casper, J; Kahl, C; Basara, N; Sayer, H G; Behre, G; Theurich, S; Christopeit, M; Mohren, M; Reichle, A; Metzner, B; Ganser, A; Stadler, M; Uharek, L; Balleisen, L; Hinke, A; Hinke, R; Niederwieser, D

2014-03-01

Since the outcome of relapsed/refractory aggressive non-Hodgkin's lymphoma (NHL) is highly variable, a risk-adapted treatment approach was evaluated. After two cycles of DHAP, patients received high-dose treosulfan/etoposide/carboplatinum (TEC) and autologous stem cell rescue. After TEC, low-risk patients with late relapse (>1 year after first CR who achieved CR after DHAP received no further treatment. Patients with late relapse who achieved CR or PR only after TEC underwent a second cycle of TEC. High-risk patients with early relapse/refractory disease received treosulfan/fludarabine followed by allogeneic transplantation. Rituximab was added in patients with B-cell lymphoma (86%). At entry, 36% of all 57 patients had refractory disease, 32% early and 32% late relapse. During DHAP treatment, progression occurred in 32% of patients. Of 33 patients who received TEC, 5 received second TEC and 15 allogeneic transplantation. Main toxicity after TEC was oral mucositis (CTC grades 3 and 4 in 50% and 13%, respectively). In total, 42% patients achieved CR. Median OS was 21.4 months for all patients and 32.6 for those who underwent allogeneic transplantation. International prognostic index (IPI) at study entry was highly discriminative at predicting OS (P<0.0001). Risk-adapted, treosulfan-based therapy with auto- and allo-SCT is feasible. Long-term survival is possible with allogeneic transplantation.

MK2206 in Treating Younger Patients With Recurrent or Refractory Solid Tumors or Leukemia

ClinicalTrials.gov

2014-04-28

Accelerated Phase Chronic Myelogenous Leukemia; Acute Leukemias of Ambiguous Lineage; Acute Myeloid Leukemia/Transient Myeloproliferative Disorder; Acute Undifferentiated Leukemia; Aggressive NK-cell Leukemia; Atypical Chronic Myeloid Leukemia, BCR-ABL1 Negative; Blastic Phase Chronic Myelogenous Leukemia; Blastic Plasmacytoid Dendritic Cell Neoplasm; Childhood Burkitt Lymphoma; Childhood Chronic Myelogenous Leukemia; Childhood Diffuse Large Cell Lymphoma; Childhood Grade III Lymphomatoid Granulomatosis; Childhood Immunoblastic Large Cell Lymphoma; Childhood Nasal Type Extranodal NK/T-cell Lymphoma; Chronic Eosinophilic Leukemia; Chronic Myelomonocytic Leukemia; Chronic Neutrophilic Leukemia; Chronic Phase Chronic Myelogenous Leukemia; Intraocular Lymphoma; Juvenile Myelomonocytic Leukemia; Mast Cell Leukemia; Myeloid/NK-cell Acute Leukemia; Noncutaneous Extranodal Lymphoma; Post-transplant Lymphoproliferative Disorder; Primary Central Nervous System Hodgkin Lymphoma; Primary Central Nervous System Non-Hodgkin Lymphoma; Progressive Hairy Cell Leukemia, Initial Treatment; Prolymphocytic Leukemia; Recurrent Childhood Acute Lymphoblastic Leukemia; Recurrent Childhood Acute Myeloid Leukemia; Recurrent Childhood Anaplastic Large Cell Lymphoma; Recurrent Childhood Grade III Lymphomatoid Granulomatosis; Recurrent Childhood Large Cell Lymphoma; Recurrent Childhood Lymphoblastic Lymphoma; Recurrent Childhood Small Noncleaved Cell Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Mycosis Fungoides/Sezary Syndrome; Recurrent Small Lymphocytic Lymphoma; Recurrent/Refractory Childhood Hodgkin Lymphoma; Refractory Chronic Lymphocytic Leukemia; Refractory Hairy Cell Leukemia; Relapsing Chronic Myelogenous Leukemia; Secondary Acute Myeloid Leukemia; Small Intestine Lymphoma; Splenic Marginal Zone Lymphoma; Unspecified Childhood Solid Tumor, Protocol Specific; Waldenström Macroglobulinemia

Adoptive Cell Transfer Therapy Following Non-Myeloablative but Lymphodepleting Chemotherapy for the Treatment of Patients With Refractory Metastatic Melanoma

PubMed Central

Dudley, Mark E.; Wunderlich, John R.; Yang, James C.; Sherry, Richard M.; Topalian, Suzanne L.; Restifo, Nicholas P.; Royal, Richard E.; Kammula, Udai; White, Don E.; Mavroukakis, Sharon A.; Rogers, Linda J.; Gracia, Gerald J.; Jones, Stephanie A.; Mangiameli, David P.; Pelletier, Michelle M.; Gea-Banacloche, Juan; Robinson, Michael R.; Berman, David M.; Filie, Armando C.; Abati, Andrea; Rosenberg, Steven A.

2006-01-01

Purpose We investigated the combination of lymphodepleting chemotherapy followed by the adoptive transfer of autologous tumor reactive lymphocytes for the treatment of patients with refractory metastatic melanoma. Patients and Methods Thirty-five patients with metastatic melanoma, all but one with disease refractory to treatment with high-dose interleukin (IL)-2 and many with progressive disease after chemotherapy, underwent lymphodepleting conditioning with two days of cyclophosphamide (60 mg/kg) followed by five days of fludarabine (25 mg/m2). On the day following the final dose of fludarabine, all patients received cell infusion with autologous tumor-reactive, rapidly expanded tumor infiltrating lymphocyte cultures and high-dose IL-2 therapy. Results Eighteen (51%) of 35 treated patients experienced objective clinical responses including three ongoing complete responses and 15 partial responses with a mean duration of 11.5 ± 2.2 months. Sites of regression included metastases to lung, liver, lymph nodes, brain, and cutaneous and subcutaneous tissues. Toxicities of treatment included the expected hematologic toxicities of chemotherapy including neutropenia, thrombocytopenia, and lymphopenia, the transient toxicities of high-dose IL-2 therapy, two patients who developed Pneumocystis pneumonia and one patient who developed an Epstein-Barr virus-related lymphoproliferation. Conclusion Lymphodepleting chemotherapy followed by the transfer of highly avid antitumor lymphocytes can mediate significant tumor regression in heavily pretreated patients with IL-2 refractory metastatic melanoma. PMID:15800326

The Chemistry and Bioaccumulation of Copper and Other Heavy Metals By Phytoplankton in the Water Column of San Diego Harbor and Its Relationship to Ecological Assessment and Water Quality

DTIC Science & Technology

1999-09-30

A suite of PCB congeners were added to these systems and the kinetics of partitioning between bacterial and protist size classes was measured to...Interestingly, the protists that produced the highest surfactant levels were the least effective at dissolving refractory iron oxide phases (from the

Improvements in Ionized Cluster-Beam Deposition

NASA Technical Reports Server (NTRS)

Fitzgerald, D. J.; Compton, L. E.; Pawlik, E. V.

1986-01-01

Lower temperatures result in higher purity and fewer equipment problems. In cluster-beam deposition, clusters of atoms formed by adiabatic expansion nozzle and with proper nozzle design, expanding vapor cools sufficiently to become supersaturated and form clusters of material deposited. Clusters are ionized and accelerated in electric field and then impacted on substrate where films form. Improved cluster-beam technique useful for deposition of refractory metals.

BRAZING ALLOYS

DOEpatents

Donnelly, R.G.; Gilliland, R.G.; Slaughter, G.M.

1962-02-20

A brazing alloy is described which, in the molten state, is characterized by excellent wettability and flowability and is capable of forming a corrosion-resistant brazed joint. At least one component of said joint is graphite and the other component is a corrosion-resistant refractory metal. The brazing alloy consists essentially of 40 to 90 wt % of gold, 5 to 35 wt% of nickel, and 1 to 45 wt% of tantalum. (AEC)

40 CFR 471.52 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2012 CFR

2012-07-01

... 320 Molybdenum 60.9 27.0 (n) Alkaline cleaning spent baths. Subpart E—BAT Pollutant or pollutant... refractory metals alkaline cleaned Copper 0.428 0.204 Nickel 0.184 0.124 Fluoride 19.9 8.82 Molybdenum 1.68 0.745 (o) Alkaline cleaning rinse. Subpart E—BAT Pollutant or pollutant property Maximum for any 1 day...

40 CFR 471.52 - Effluent limitations representating the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2010 CFR

2010-07-01

... 320 Molybdenum 60.9 27.0 (n) Alkaline cleaning spent baths. Subpart E—BAT Pollutant or pollutant... refractory metals alkaline cleaned Copper 0.428 0.204 Nickel 0.184 0.124 Fluoride 19.9 8.82 Molybdenum 1.68 0.745 (o) Alkaline cleaning rinse. Subpart E—BAT Pollutant or pollutant property Maximum for any 1 day...

40 CFR 471.52 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2014 CFR

2014-07-01

... 320 Molybdenum 60.9 27.0 (n) Alkaline cleaning spent baths. Subpart E—BAT Pollutant or pollutant... refractory metals alkaline cleaned Copper 0.428 0.204 Nickel 0.184 0.124 Fluoride 19.9 8.82 Molybdenum 1.68 0.745 (o) Alkaline cleaning rinse. Subpart E—BAT Pollutant or pollutant property Maximum for any 1 day...

40 CFR 471.52 - Effluent limitations representating the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2011 CFR

2011-07-01

... 320 Molybdenum 60.9 27.0 (n) Alkaline cleaning spent baths. Subpart E—BAT Pollutant or pollutant... refractory metals alkaline cleaned Copper 0.428 0.204 Nickel 0.184 0.124 Fluoride 19.9 8.82 Molybdenum 1.68 0.745 (o) Alkaline cleaning rinse. Subpart E—BAT Pollutant or pollutant property Maximum for any 1 day...

40 CFR 471.51 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2013 CFR

2013-07-01

... range of 7.5 to 10.0 at all times. (n) Alkaline cleaning spent baths. Subpart E—BPT Pollutant or...-pounds) of refractory metals alkaline cleaned Copper 0.635 0.334 Nickel 0.641 0.424 Fluoride 19.9 8.82... all times. (o) Alkaline cleaning rinse. Subpart E—BPT Pollutant or pollutant property Maximum for any...

Refractory ceramic compositions and method for preparing same

DOEpatents

Holcombe, Jr., Cressie E.; Morrow, Margaret K.

1976-07-13

This invention relates to ceramic compositions of tungsten and tantalum oxides including 0 to 33 1/3 mole percent of a metal oxide such as hafnia. These ceramics are characterized by melting points greater than about 1400.degree.C and selectively controlled coefficients of thermal expansion of essentially zero to a negative value in the temperature range of 20.degree. to 1000.degree.C.

The Analysis and Modeling of Phase Stability and Multiphase Designs in High Temperature Refractory Metal-Silicon-Boron Alloys

DTIC Science & Technology

2009-01-27

high temperature mechanical properties , it was confirmed that the three phase eutectic structure exhibited exceptionally high strength and creep...microstructurc constituent, offer an attractive property balance of high melting temperature, oxidation resistance and useful high temperature mechanical ...design of new multiphase high-temperature alloys with balanced environmental and mechanical properties . 15. SUBJECT TERMS Phase Stability, Alloying

Young Investigator Program: Quasi-Liquid Grain Boundary Films in Refractory Metals

DTIC Science & Technology

2010-01-15

have been conducted for W using various dopants with significantly different effectiveness [48, 52], enabling a critical test of the hypothesized...thickness vs. temperature for dopant -saturated W specimens. (b) The experimental sintering (densification) rates. Reprinted from an AFOSR supported...the colloidal theory (Fig. 16b). The basic concepts can be explained as follows. By reducing the temperature, or dopant activity, a quasi-liquid

Development and Processing of Nickel Aluminide-Carbide Alloys

NASA Technical Reports Server (NTRS)

Newport, Timothy Scott

1996-01-01

With the upper temperature limit of the Ni-based superalloys attained, a new class of materials is required. Intermetallics appear as likely candidates because of their attractive physical properties. With a relatively low density, high thermal conductivity, excellent oxidation resistance, high melting point, and simple crystal structure, nickel aluminide (NiAl) appears to be a potential candidate. However, NiAl is limited in structural applications due to its low room temperature fracture toughness and poor elevated temperature strength. One approach to improving these properties has been through the application of eutectic composites. Researchers have shown that containerless directional solidification of NiAl-based eutectic alloys can provide improvement in both the creep strength and fracture toughness. Although these systems have shown improvements in the mechanical properties, the presence of refractory metals increases the density significantly in some alloys. Lower density systems, such as the carbides, nitrides, and borides, may provide NiAl-based eutectic structure. With little or no information available on these systems, experimental investigation is required. The objective of this research was to locate and develop NiAl-carbide eutectic alloys. Exploratory arc-melts were performed in NiAl-refractory metal-C systems. Refractory metal systems investigated included Co, Cr, Fe, Hf, Mo, Nb, Ta, Ti, W, and Zr. Systems containing carbides with excellent stability (i.e.,HfC, NbC, TaC, TiC, and ZrC) produced large blocky cubic carbides in an NiAl matrix. The carbides appeared to have formed in the liquid state and were randomly distributed throughout the polycrystalline NiAl. The Co, Cr, Fe, Mo, and W systems contained NiAl dendrites with a two-phase interdendritic microconstituent present. Of these systems, the NiAl-Mo-C system had the most promising microstructure for in-situ composites. Three processing techniques were used to evaluate the NiAl-Mo-C system: arc-melting, slow cooling, and containerless directional solidification. Arc-melting provided a wide range of compositions in an economical and simple fashion. The slow cooled ingots provided larger ingots and slower cooling rates than arc-melting. Directional solidification was used to produce in-situ composites consisting of NiAl reinforced with molybdenum carbides.

Explosive Welding in the 1990's

NASA Technical Reports Server (NTRS)

Lalwaney, N. S.; Linse, V. D.

1985-01-01

Explosive bonding is a unique joining process with the serious potential to produce composite materials capable of fulfilling many of the high performance materials capable of fulfilling many of the high performance materials needs of the 1990's. The process has the technological versatility to provide a true high quality metallurgical compatible and incompatible systems. Metals routinely explosively bonded include a wide variety of combinations of reactive and refractory metals, low and high density metals and their alloys, corrosion resistant and high strength alloys, and common steels. The major advantage of the process is its ability to custom design and engineer composites with physical and/or mechanical properties that meet a specific or unusual performance requirement. Explosive bonding offers the designer unique opportunities in materials selection with unique combinations of properties and high integrity bonds that cannot be achieved by any other metal joining process. The process and some applications are discussed.

The lunar core and the origin of the moon

NASA Astrophysics Data System (ADS)

Newsom, H. E.

1984-05-01

The results of recent analyses of concentrations of refractory siderophile elements molybdenum and rhenium in lunar rock samples suggest that most siderophile elements in lunar crustal rocks and mare basalts are significantly less concentrated than in the earth's mantle and much less than in chondrite meteorites. The depletion of siderophile elements in the samples implies the existence of a metal core, and the amount of metal in the core is directly related to the conditions under which segregation occurs. The consequences of the data are discussed in terms of three theoretical models of lunar evolution: a terrestrial origin model; a terrestrial origin model which takes metal segregation into account; and an independent origin model. It is shown that less metal is needed for a terrestrial origin because the earth's mantle was already partially depleted in siderophile elements due to the formation of the earth core.

Behaviour of implanted arsenic during rapid thermal annealing of Ti on Si

NASA Astrophysics Data System (ADS)

Ponpon, J. P.; Saulnier, A.; Stuck, R.

1987-11-01

The reaction during rapid thermal annealing of the Ti-Si couple with arsenic implanted either into titanium or into silicon has been investigated from the point of view of suicide formation kinetics and impurity redistribution. In contrast with similar experiments on other refractory metals, tungsten for example, the reaction is not blocked by the presence of arsenic but a temperature and dose dependent impurity effect leading to a lowering of the growth rate of the disilicide phase is observed. This has been attributed to arsenic segregation in the grain boundaries of the growing suicide which reduces the transport of silicon via easy diffusion paths towards the unreacted metal or a metal rich suicide phase. Arsenic, when present in the metal, has been found to produce the same effects as oxygen at the early beginning of the annealing. However, after the reaction has started the respective behaviour and influence of arsenic and oxygen become completely different.

Base-metal saturation of refractory carbide coatings produced by enhanced ceramic jets in electrothermally exploded powder spray

NASA Astrophysics Data System (ADS)

Tamura, Hideki; Itaya, Masanobu

2000-09-01

Tungsten carbide and tantalum carbide were sprayed onto substrates of mild steel by the electrothermally exploded powder spray (ELTEPS) process. High-speed x-ray radiography revealed that tungsten-carbide jets of molten particles guided inside a nozzle exhibited denser flow than unguided jets at the substrate. The velocity of the jet was approximately 800 m/s at the early stage of jetting. The ceramic coatings obtained from the guided spray consisted of carbides of a few to tens of micrometers in size, which were saturated by the base metal up to the top of the coating. The coatings exhibited diffusion of the sprayed ceramics and base metal at the interface of the deposit and substrate. The enhancement of the jet flow formed a microstructure of the ceramic coating, which was saturated by the base metal even without post heat treatment.

Protective sheath for a continuous measurement thermocouple

DOEpatents

Phillippi, R.M.

1991-12-03

Disclosed is a protective thermocouple sheath of a magnesia graphite refractory material for use in continuous temperature measurements of molten metal in a metallurgical ladle and having a basic slag layer thereon. The sheath includes an elongated torpedo-shaped sheath body formed of a refractory composition and having an interior borehole extending axially therethrough and adapted to receive a thermocouple. The sheath body includes a lower end which is closed about the borehole and forms a narrow, tapered tip. The sheath body also includes a first body portion integral with the tapered tip and having a relatively constant cross section and providing a thin wall around the borehole. The sheath body also includes a second body portion having a relatively constant cross section larger than the cross section of the first body portion and providing a thicker wall around the borehole. The borehole terminates in an open end at the second body portion. The tapered tip is adapted to penetrate the slag layer and the thicker second body portion and its magnesia constituent material are adapted to withstand chemical attack thereon from the slag layer. The graphite constituent improves thermal conductivity of the refractory material and, thus, enhances the thermal responsiveness of the device. 4 figures.

Protective sheath for a continuous measurement thermocouple

DOEpatents

Phillippi, R. Michael

1991-01-01

Disclosed is a protective thermocouple sheath of a magnesia graphite refractory material for use in continuous temperature measurements of molten metal in a metallurgical ladle and having a basic slag layer thereon. The sheath includes an elongated torpedo-shaped sheath body formed of a refractory composition and having an interior borehole extending axially therethrough and adapted to receive a thermocouple. The sheath body includes a lower end which is closed about the borehole and forms a narrow, tapered tip. The sheath body also includes a first body portion integral with the tapered tip and having a relatively constant cross section and providing a thin wall around the borehole. The sheath body also includes a second body portion having a relatively constant cross section larger than the cross section of the first body portion and providing a thicker wall around the borehole. The borehole terminates in an open end at the second body portion. The tapered tip is adapted to penetrate the slag layer and the thicker second body portion and its magnesia constituent material are adapted to withstand chemical attack thereon from the slag layer. The graphite constituent improves thermal conductivity of the refractory material and, thus, enhances the thermal responsiveness of the device.

Metal-dielectric interactions

NASA Technical Reports Server (NTRS)

Buckley, D. H.

1979-01-01

Metal direlectric surface interactions and dielectric films on metal substrates were investigated. Since interfacial interaction depends so heavily on the nature of the surfaces, analytical surface tools such as Auger emission spectroscopy, X-ray photoelectron spectroscopy and field ion microscopy were used to assist in surface and interfacial characterization. The results indicate that with metals contacting certain glasses in the clean state interfacial, bonding produces fractures in the glasses while when a film such as water is present, fractures occur in the metal near the interface. Friction forces were used to measure the interfacial bond strengths. Studies with metals contacting polymers using field ion microscopy revealed that strong bonding forces could develop being between a metal and polymer surface with polymer transferring to the metal surface in various ways depending upon the forces applied to the surface in contact. With the deposition of refractory carbides, silicides and borides onto metal and alloy substrates the presence of oxides at the interface or active gases in the deposition plasma were shown to alter interfacial properties and chemistry. Auger ion depth profile analysis indicated the chemical composition at the interface and this could be related to the mechanical, friction, and wear behavior of the coating.

Transcription factor Stat5a/b as a therapeutic target protein for prostate cancer

PubMed Central

Liao, Zhiyong; Lutz, Jacqueline; Nevalainen, Marja T.

2009-01-01

Prostate cancer is the most common non-cutaneous cancer in Western males. The majority of prostate cancer fatalities are caused by development of castration-resistant growth and metastatic spread of the primary tumor. The average duration of the response of primary prostate cancer to hormonal ablation is less than 3 years, and 75% of prostate cancers in the United States progress to hormone-refractory disease. The existing pharmacological therapies for metastatic and/or hormone-refractory prostate cancer do not provide significant survival benefit. This review summarizes the importance of transcription factor Stat5 signaling in the pathogenesis of prostate cancer and discusses the molecular basis why inhibition of Stat5a/b could be used as a therapeutic strategy for prostate cancer. PMID:19914392

Proton pump inhibitor-refractory gastroesophageal reflux disease: challenges and solutions

PubMed Central

Mermelstein, Joseph; Chait Mermelstein, Alanna; Chait, Maxwell M

2018-01-01

A significant percentage of patients with gastroesophageal reflux disease (GERD) will not respond to proton pump inhibitor (PPI) therapy. The causes of PPI-refractory GERD are numerous and diverse, and include adherence, persistent acid, functional disorders, nonacid reflux, and PPI bioavailability. The evaluation should start with a symptom assessment and may progress to imaging, endoscopy, and monitoring of esophageal pH, impedance, and bilirubin. There are a variety of pharmacologic and procedural interventions that should be selected based on the underlying mechanism of PPI failure. Pharmacologic treatments can include antacids, prokinetics, alginates, bile acid binders, reflux inhibitors, and antidepressants. Procedural options include laparoscopic fundoplication and LINX as well as endoscopic procedures, such as transoral incisionless fundoplication and Stretta. Several alternative and complementary treatments of possible benefit also exist. PMID:29606884