Energy Technology Data Exchange (ETDEWEB)

A hydrous oxide film for the application as dielectric film is synthesized by immersion of pure aluminum in hot water. From a Rutherford backscattering analysis, the ratio of aluminum to oxygen atoms was found to be 3:2 in the anodized aluminum oxide film, and 2:1 in the hydrous oxide layer. Anodization of the hydrous oxide layer was more effective for the transition of amorphous anodic oxides to the crystalline aluminum oxides.

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MCrAlY coatings are widely used on hot section components of gas turbines to provide hot corrosion and/or oxidation protection by formation of an oxide layer on the surface. As the protective oxide scale exfoliates during service, aluminum from the coating diffuses outward for reformation of the protective scale. Aluminum may also diffuse inward due to the differences in composition between the coating and the substrate. Thus, the coatings degrade due to oxidation, oxide scale spallation, and inward and outward diffusion of aluminum. Service life of these coatings is controlled by the aluminum content in the coating, operating temperature and start- shutdown cycles. In-service degradation of CoCrAlY and CoNiCrAlY coatings is presented. A procedure to predict the remaining service life of coatings ...

Energy Technology Data Exchange (ETDEWEB)

In a work studying the corrosion and tarnishing properties of a variety of copper alloys, the alloy Cu-A110-Sn5 was found to show an excellent corrosion resistance in neutral solutions, where copper and most conventional Cu alloys are covered by thick nonprotective surface layers. The passive films formed on this alloy were characterized with electrochemical and photoelectrochemical methods. The pH dependence of the passivation and of the photocurrent behavior of the Cu-A110-Sn5 alloy clearly indicates that the passivity of this alloy in neutral solutions is due to a formation of passive film enriched with aluminum oxide. At corrosion potential a strong increase in the corrosion resistance with time is due to a gradual enrichment of the surface with aluminum oxide. This can be seen in the photocurrent spectra which change from cooper-type to aluminum-type with time. At higher ...

Science.gov (United States)

Aluminum, due to its low density and low cost, is a key material for future lightweight applications. However, like other structural materials, aluminum is subject to various forms of corrosion damage that annually costs the United States approximately 5% of its GNP [1]. The main goal is to investigate the effects of various solution anions on aluminum surfaces, and specifically probe pit initiation and inhibition. Using surface analysis techniques including X-ray photoelectron spectroscopy, Auger electron spectroscopy, and scanning electron microscopy, results have been correlated with those obtained from electrochemical methods and a radiolabeling technique developed in the Wieckowski laboratory. Analysis of data has indicated that important variables include type of anion, solution pH, and applied electrode potential. While aggressive anions such as chloride are usually studied to elucidate corrosion processes to work ...

Energy Technology Data Exchange (ETDEWEB)

Apparatus and methods for generating heat and electricity from the consumption of a variety of aluminum products comprise: (A) a reaction chamber containing an aqueous electrolyte solution and adapted for introduction therein of aluminum pieces of various shapes and sizes up to a certain maximum predetermined size and for effecting a chemical reaction between said aqueous electrolyte and said aluminum pieces yielding aluminum hydroxide and an intermediate reactant; (B) means for feeding said aluminum pieces into said reaction chamber in small quantities upon demand; (C) means for removing the heat generated in said chamber as a result of said reaction; (D) means for removing said aluminum hydroxide reaction product; and (E) means for oxidizing said intermediate reactant in an electrochemical cell, thereby generating electrical energy. The ...

Energy Technology Data Exchange (ETDEWEB)

The theoretical principles underlying the formation of oxide and, in particular, anodic oxide coatings on metals produced by chemical oxidation, anodizing in solutions, and anodizing in cold plasmas are reviewed. The mechanisms and conditions of anodic oxidation are described, and the structure of anodic oxide coatings on aluminum, magnesium, beryllium, zinc, cadmium, iron, cobalt, nickel, titanium, zirconium, tantalum, and chromium alloys is examined. Attention is also given to various applictins of anodized coatings. 54 references.

Energy Technology Data Exchange (ETDEWEB)

In a method for formulating a multi-component explosive composition, the steps are described comprising: (a) providing a defined body of unconsolidated particulate aluminum fuel granules having an average particle size within the range of 1/64-1/4 inch and an average bulk density within the range of 0.2-1.0 gm/cc; (b) providing a phase oxidizing liquid; and (c) flooding said body of particulate aluminum fuel of step (a) with the oxidizing liquid of step (b) to provide a bulk density of said mixture of oxidizing liquid and particulate aluminum fuel mass within the range of 1.2-1.7 gm/cc and provide an explosive formulation detonable at 20 C in a diameter of 4 inches by a one pound pentolite booster.

British Library Electronic Table of Contents (United Kingdom)

We report the fabrication and characterization of glucose-tolerant Raney-platinum cathodes for oxygen reduction in potentially implantable glucose fuel. Fabricated by extraction of aluminum from 1mm thin platinum-aluminum bi-layers annealed at 300^oC, the novel cathodes show excellent resistance against hydrolytic and oxidative attack. This renders them superior over previous cathodes fabricated from hydrogel-bound catalyst particles. Annealing times of 60, 120, and 240min result in approximately 400-550nm thin porous films (roughness factors ~100-150), which contain platinum and aluminum in a ratio of ~9:1. Aluminum release during electrode operation can be expected to have no significant effect on physiological normal levels, which promises good biocompatibility. Annealing time has a dis...

British Library Electronic Table of Contents (United Kingdom)

l-Carnitine is a critical metabolite indispensable for the metabolism of lipids as it facilitates fatty acid transport into the mitochondrion where b-oxidation occurs. Human astrocytes (CCF-STTG1 cells) and hepatocytes (HepG2 cells) exposed to aluminum (Al) and hydrogen peroxide (H2O2), were characterized with lower levels of l-carnitine, diminished b-oxidation, and increased lipid accumulation compared to the controls. g-Butyrobetainealdehyde dehydrogenase (BADH) and butyrobetaine dioxygenase (BBDOX), two key enzymes mediating the biogenesis of l-carnitine, were sharply reduced during Al and H2O2 challenge. Exposure of the Al and H2O2-treated cells to a-ketoglutarate (KG), led to the recovery of l-carnitine production with the concomitant reduction in ROS levels. It appears that the chann...

Energy Technology Data Exchange (ETDEWEB)

Y{sub 2-x}Tb{sub x}SiO{sub 5} and Y{sub 2-x}Eu{sub x}SiO{sub 5} nanophosphors with seven different kinds of silicate sources were synthesized by sol-gel method. The structures have been investigated to be composed of nanometer-size grains of 30-60 nm through X-ray diffraction (XRD) and scanning electron microscopy (SEM) was used to compare the different morphology of patterns from seven different silicon sources. The photoluminescence of Y{sub 2-x}Tb{sub x}SiO{sub 5} was investigated as a function of silicate sources and the results revealed that these nanometer materials showed the characteristic emission {sup 5}D{sub 4} {yields} {sup 7}F{sub J} (J 6, 5, 4, 3) of Tb ions. The characteristic emission {sup 5}D{sub 0} {yields} {sup 7}F{sub J} (J = 1, 2, 4) of Eu ions was also found in the materials of Y{sub 2-x}Eu{sub x}SiO{sub 5}.

Energy Technology Data Exchange (ETDEWEB)

Whereas supersaturated aluminum alloys demonstrate enhanced passivity, conventional aluminum alloys spontaneously pit in air-saturated chloride solutions. We have concentrated on three areas: evaluation and characterization of Al-W alloys, which exhibit the best corrosion performance of any alloy system studied to date; characterization of the passive-film structure of Al-Mo alloys; and production and characterization of Al-W and Al-Ta powders, which will be used for compaction into bulk material. Surface analysis of the Al-W passive films formed during polarization show surprising little oxidized solute compared to other alloys. These results indicate that the barrier layer formation and electrostatic repulsion mechanisms used to explain the passivity of other alloys are not involved here. Instead the W may act to stabilize the passive film structure in a way similar to the way molybdenum acts in Al-Mo alloys. That is ...

Science.gov (United States)

"Precision manufacture of ceramic parts with CNC machining capability for aerospace, lasers, semiconductors and other industries. Materials include alumina, zirconia, glass, ferrites, silicon carbide, silicon nitride, sapphire, cordierite, mullite and others. A.C.T. has seen the number of applications and demand for high-realiability ceramics (aluminum oxide, zirconia, glass, ferrites, silicon carbide, silicon nitride, sapphire, cordierite, mullite, etc...) increase continually within the aerospace, computer and the industrial markets."

British Library Electronic Table of Contents (United Kingdom)

Magnetic pulse welding is a solid state impact welding process, similar to explosive welding, which produces metallurgical bond by oblique high-speed impact between two metal bodies. This violent impact removes the metal surface oxide layers and then joins the two atomic level clean metal surfaces together by the incidental compression pressure. The impact velocity is at 200?400?m/s and the being welded metal surface undergoes severe plastic deformation with strain rate in the order of 106?107?s?1. The ultrafine-grained structure was observed on the welded interface. This article studied two types of similar material lap joint interfaces and the base metals were aluminum alloy 6061 and copper alloy 110. Nano-indentation testing shows that the welded interfaces have significantly greater ha...

International Nuclear Information System (INIS)

The total hemispherical emittance of an oxide film that formed on 6061-T6 aluminium alloy parts in the Tower Shielding Reactor-II at Oak Ridge National Laboratory was measured from 295 to 773 K using an emissometer and/or a calorimeter. The emittance of this film was critically needed for heat transfer calculations in a simulated loss-of-coolant accident of the reactor. X-ray diffraction analysis identified the film as boehmite (Al_2O_3 x H_2O), which dehydrated to alumina (Al_2O_3) upon heating above 473 K. The measured emittances for the alumina film are in excellent agreement with published values for anodized aluminum films and for bulk alumina. Published values of the emittance of boehmite could not be found for comparison, but evidence is presented that some anodization processes for aluminum yield boehmite and not alumina films.

Energy Technology Data Exchange (ETDEWEB)

The emittance of aluminum components exposed to low-temperature aqueous solutions were required for thermal analysis of a Loss of Cooling Accident for the Savannah River Site production reactors. Experimental data for the thickness and emittance of oxide films formed under these conditions were collected and reviewed. Correlations were developed for the oxide film thickness and corresponding total hemispherical emittance. Film thickness and emittance were also measured for the specific conditions of interest in order to verify the predictions based on the literature data. After one year of exposure in 30deg C reactor moderator, the aluminum oxide film thickness is predicted to be 6.4 [mu]m[+-]10%; this value is relatively insensitive to exposure time. Some phenomena which would tend to yield thicker oxide films in the reactor environment relative to those ...

Energy Technology Data Exchange (ETDEWEB)

A concept is shown for a fully reusable, Earth-to-orbit launch vehicle with horizontal takeoff and landing, employing an air-turborocket for low speed and a rocket for high-speed acceleration, both using liquid hydrogen for fuel. The turborocket employs a modified liquid air cycle to supply the oxidizer. The rocket uses 90% pure liquid oxygen as its oxidizer that is collected from the atmosphere, separated, and stored during operation of the turborocket from about Mach 2 to 5 or 6. The takeoff weight and the thrust required at takeoff are markedly reduced by collecting the rocket oxidizer in-flight. This article shows an approach and the corresponding technology needs for using air liquefaction and enrichment system propulsion in a single-stage-to-orbit (SSTO) vehicle. Reducing the trajectory altitude at the end of collection reduces the wing area and increases payload. The use of state-of-the-art materials, such as ...

Energy Technology Data Exchange (ETDEWEB)

Metals for potential use in the dissociator and the synthesizer reactors of a distributed solar receiver thermochemical transport loop utilizing SO/sub 3//SO/sub 2//O/sub 2/ molecular chemistry were tested in SO/sub 2//O/sub 2/ mixtures at 500/sup 0/C and 900/sup 0/C, respectively, for times of up to four weeks. They included titanium, aluminum and nickel, and iron-base, nickel-base and cobalt-base superalloys. Weight gain measurements determine the oxidation/sulfidation kinetics. Electron microprobe analysis identifies any possible penetration of oxygen and sulfur into the metal and the formation of internal oxides and sulfides. The most promising candidates as a result of these tests are the cobalt-base superalloys.

Science.gov (United States)

films and cylinders of rare earth doped yttrium aluminum garnets. ... We knew that yttrium aluminum garnet (YAG) could be doped with ...

Science.gov (United States)

Scratch and Corrosion Resistance of an Aluminum Flange with an Electron Beam Modified Seal Edge

Energy Technology Data Exchange (ETDEWEB)

Aluminum is a principal element in alkaline nuclear sludge waste stored in high level waste (HLW) tanks at the Savannah River Site. The mass of sludge in a HLW tank can be reduced through the caustic leaching of aluminum, i.e. converting aluminum oxides (gibbsite) and oxide-hydroxides (boehmite) into soluble hydroxides through reaction with a hot caustic solution. The temperature limits outlined by the chemistry control program for HLW tanks to prevent caustic stress corrosion cracking (CSCC) in concentrated hydroxide solutions will potentially be exceeded during the sludge mass reduction (SMR) campaign. Corrosion testing was performed to determine the potential for CSCC under expected conditions. The experimental test program, developed based upon previous test results and expected conditions during the current SMR campaign, consisted of electrochemical and mechanical testing to ...

Energy Technology Data Exchange (ETDEWEB)

the medium to long freezing range alloys of aluminum such as A356, A357, A206, 319 for example are known to exhibit dispersed porosity, which is recognized as a factor affecting ductility, fracture toughness, and fatigue resistance of light alloy castings. The local thermal environment, for example, temperature gradient and freezing from velocity, affect the mode of solidification which, along with alloy composition, heat treatment, oxide film occlusion, hydrogen content, and the extent to which the alloy contracts on solidification, combine to exert strong effects on the porosity formation in such alloys. In addition to such factors, the availability of liquid metal and its ability to flow through the partially solidified casting, which will be affect by the pressure in the liquid metal, must also be considered. The supply of molten metal will thus be controlled by the volume of the riser available for feeding the particular casting location, ...

Science.gov (United States)

Feasibility of depositing continuous films of nano-porous alumino-silicates, primarily zeolites and MCM-41, on metallic and non-metallic substrates was examined with an aim to develop membranes for separation of gaseous mixtures and also for application as hydrogen storage material. Mesoporous silica was deposited in-side the pores of these nano-porous disks with an aim to develop membranes for selective separations. Our study involves supported zeolite film growth on substrates using in-situ hydrothermal synthesis. Faujasite, Silicalite and Mesoporous silica have been grown on various metallic and non-metallic supports. Metallic substrates used for film growth included anodized titanium, sodium hydroxide treated Titanium, Anodized aluminum, and sintered copper. A non-metallic substrate used was nano-porous aluminum oxide. Zeolite film growth was characterized using Scanning Electron Microscope (AMRAY 1820) and High ...

Energy Technology Data Exchange (ETDEWEB)

A number of screening tests were performed to determine ion species that effectively reduce wear rates when implanted in four industrial steels. Ball bearing steel 100Cr6 (AISI 52100) showed a wear rate reduction by a factor of 20 when implanted with carbon dioxide to a dose of 5x10{sup 17} cm{sup -2} with a non-mass-separated ion beam and by a factor of {>=}20 when implanted with 5x10{sup 17} cm{sup -2} oxygen ions. For the ferritic and martensite steels X90CrMoV18 (AISI 440B, unhardened and hardened) also a strong wear reduction after implantation of oxygen ions was found. Co-implantation of aluminum and oxygen also reduces wear rates of X90CrMoV18, of S6-5-2 (AISI M2), and of 100Cr6, respectively. For comparison, thin oxide layers were grown in a low-temperature thermal oxidation process. These experiments also yielded reduced wear rates by a factor of 10. The surfaces were investigated and characterized by XPS, SIMS, ...

Energy Technology Data Exchange (ETDEWEB)

The operational limits of the Tower Shielding Reactor-2 (TSR-2) have been revised to account for placing the reactor in a beam shield, which reduces convection cooling during a loss-of-coolant accident (LOCA). A detailed heat transfer analysis was performed to set operating time limits which preclude fuel damage during a LOCA. Since a LOCA is survivable, the pressure boundary need not be safety related, minimizing seismic and inspection requirements. Measurements of reactor component emittance for this analysis revealed that aluminum oxidized in water may have emittance much higher than accepted values, allowing higher operating limits than were originally expected. These limits could be increased further with analytical or hardware improvements. 5 refs., 7 figs.

Energy Technology Data Exchange (ETDEWEB)

The burning characteristics of fuel droplets containing nano and micron-sized aluminum particles were investigated. Particle size, surfactant concentration, and the type of base fluid were varied. In general, nanosuspensions can last much longer than micron suspensions, and ethanol-based fuels were found to achieve much better suspension than n-decane-based fuels. Five distinctive stages (preheating and ignition, classical combustion, microexplosion, surfactant flame, and aluminum droplet flame) were identified for an n-decane/nano-Al droplet, while only the first three stages occurred for an n-decane/micron-Al droplet. For the same solid loading rate and surfactant concentration, the disruption and microexplosion behavior of the micron suspension occurred later with much stronger intensity. The intense droplet fragmentation was accompanied by shell rupture, which caused a massive explosion of particles, and most of them were burned during this ...

Energy Technology Data Exchange (ETDEWEB)

In addition to ceramics, alloys such as tool steel and nickel- and iron-based superalloys are being considered for high temperature applications such as missile bearings and low heat rejection engines. Studies were made to lubricate a nickel-based superalloy at 500{degrees}C, by using a vaporized aryl phosphate ester, at a concentration of 0.1% in air. From deposition and wear studies it was found that it was impossible to form a good polymeric coating on the superalloy surface. Energy dispersive X-ray analyzer (EDXA) analysis showed that this was due to minute quantities of aluminum in the alloy segregating to the surface, upon being heated to 500{degrees}C, forming a passive oxide coating. It was necessary to activate the surface, in order to lubricate the material successfully. A method of activation by electrodepositing the surface with a layer of iron oxide was developed. Once activated, a good lubricous polymer was ...

Science.gov (United States)

Aluminum electrolytic capacitors are presently not allowed ..... specified for commercial aluminum electrolytic capacitors of similar rating. ...

Science.gov (United States)

... GRIT-BLAST/SILANE (GBS) ... GRIT-BLAST/SILANE (GBS) ALUMINUM SURFACE PREPARATION FOR STRUCTURAL ADHESIVE BONDING 5b. ...

Science.gov (United States)

... Accession Number : ADA547552. Title : Aluminum-Zinc (Al-Zn) Dust Analyses for Recycling Purposes. Descriptive Note : Technical rept. ...

Energy Technology Data Exchange (ETDEWEB)

The adhesion of a Mg:Ag cathode to the tris-(8-hydroxyquinoline) aluminum (Alq{sub 3}) in organic light emitting devices (OLEDs) can be greatly enhanced by a remote plasma treatment of the Alq{sub 3} layer using either air or N{sub 2} prior to metal deposition. The altered surface properties which lead to increased sticking coefficients of Mg and Ag, as well as enhanced adhesion, are attributed to the introduction of new functional groups into the organic layer, as observed by X-ray photoelectron spectroscopy (XPS). The storage life of the plasma treated devices in air without any capping treatment, as judged by a visible deterioration of the cathode, was increased by approximately five to six times compared to untreated OLEDs. Current-voltage characteristics and EL efficiency, however, were shown to deteriorate for devices incorporating either an air or an N{sub 2} plasma treated Alq{sub 3} layer. For OLEDs subjected to short treatment times with an N{sub 2} ...

International Nuclear Information System (INIS)

Thin PTFE membranes were prepared by coating the PTFE dispersion onto the aluminum films. Thus the thin crosslinked PTFE (RX-PTFE) membranes were obtained by means of electron beam irradiation above the melting temperature of PTFE under oxygen-free atmosphere. The RX-PTFE membranes were pre-irradiated and grafted by styrene with or without divinylbenzene (DVB) in liquid phase. The existence of DVB accelerated the initial grafting rate. The styrene grafted RX-PTFE membranes are white colored, on the other hand, the styrene/DVB grafted RX-PTFE membranes are colorless. The proton exchange membranes (PEMs) were obtained by sulfonating the grafted membranes using chlorosulfonic acid. The ion exchange capacity (IEC) values of the PEMs ranging from 1.5 to 2.8 meq/g were obtained. The PEMs made from the styrene/DVB grafted membranes showed higher chemical stability than those of the styrene grafted membranes under oxidative circumstance.

Science.gov (United States)

A new method, near-infrared laser desorption/ionization aerosol mass spectrometry (NIR-LDI-AMS), is described for the real time analysis of organic aerosols at atmospherically relevant mass loadings. Use of a single NIR laser pulse to vaporize and ionize particle components deposited on an aluminum probe results in minimal fragmentation to produce exclusively intact pseudomolecular anions at [M-H](-). Limits of detection (total particulate mass sampled) for oxidized compounds of relevance to atmospheric primary and secondary organic aerosol range from 89 fg for pinic acid to 8.8 pg for cholesterol. NIR-LDI-AMS was used in conjunction with the University of Vermont Environmental Chamber to study secondary organic aerosol (SOA) formation from ozonolysis of limonene at total aerosol mass loadings ranging from 3.2 to 25.0 ?g m(-3) and with a time resolution of several minutes. NIR-LDI-AMS permitted direct delineation between gas-phase, homogeneous ...

Energy Technology Data Exchange (ETDEWEB)

A heat resistant nickel base alloy which is excellent in not only hot and cold workability but also high temperature strength properties and which also possesses satisfactory oxidation resistance. The nickel base alloy consists essentially of 0.001-0.15 percent carbon, 0.0005-0.05 percent calcium, 20.0-126.0 percent chromium, 4.7-9.4 percent cobalt, 5.0-16.0 percent molybdenum, 0.5-4.0 percent tungsten, with the total of molybdenum plus tungsten being from 9.0 to 16.5 percent, and the balance nickel and inevitable impurities. The alloy may further contain one selected from the group consisting of (1) 0.3-1.5 percent aluminum and 0.1-1.0 percent titanium, (2) 0.001-0.30 percent at least one of yttrium and rare earth elements, and (3) 0.001-1.0 percent at least one of niobium, vanadium and tantalum, whereby the aforementioned characteristics are further enhanced.

International Nuclear Information System (INIS)

SiAlONs are ceramics with high potential as biomaterials due to their chemical stability, associated with suitable mechanical properties, such as high fracture toughness and fracture resistance. The objective of this work was to investigate the mechanical properties and the cytotoxicity of these ceramic materials. Three different compositions were prepared, using silicon nitride, aluminum nitride and a rare earth oxide mixture as starting powders, yielding Si_3N_4-SiAlON composites or pure SiAlON ceramics, after hot-pressing at 1750 deg. C, for 30 min. The sintered samples were characterized by X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM). Furthermore, hardness and fracture toughness were determined using the Vicker's indentation method. The biological compatibility was evaluated by in vitro cytotoxicity tests. Ceramic with elevated hardness, ranging between 17 and 21 GPa, and high fracture toughness of 5 to 6 MPa ...

Energy Technology Data Exchange (ETDEWEB)

Cyclic voltammetry (CV), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) were employed to investigate the electrodeposition of Eu and Al in an LiCl-KCl eutectic melt containing Eu{sup 2+} and Al{sup 3+} at 450 deg. C. In order to deposit a pure Eu and Al alloy, the stoichiometrically lower concentration of Al{sup 3+} than that of Eu{sup 2+} and Al wires as a counter electrode was introduced into the bath of LiCl-KCl melt for the electrodeposition. The electrodeposition takes place at a potential more negative than -1.95 V vs. Ag|Ag{sup +} while the deposit is oxidized at more positive potential than -1.92 V. Two new reduction peaks and an anodic peak on a W working electrode were observed at -2.39 V, -2.42 V, and -2.1 V, vs. Ag|Ag{sup +}, respectively, suggesting that the potential window of the Al system in LiCl-KCl melt can be extended to -2.43 V vs. Ag|Ag{sup +}. The EDS analysis indicated that AlEu can be deposited at the potential ...

International Nuclear Information System (INIS)

The hazardous and toxic nature of some of the constituent such as nitrite in the aquaculture wastewater is of major concern. Present study focuses the removal of nitrite from the aquaculture wastewater prior to disposal. Effect of certain operational parameters such as electrode material, current density, initial pH, and electrode spacing on nitrite removal from aquaculture wastewater was elucidated. Better nitrite removal efficiency achieved when nickel used as compared to stainless steel, graphite and aluminum electrodes. Nitrite removal is positively related to the current density however, increase is up to 31.4% when current density increased from 2.5 to 9.3 mA/cm/sup 2/. Further increase in current density does not improve the process efficiency. Removal efficiency of electrochemical process decreased with the increase in initial pH of test solution. However, with the passage of time this difference is diminishing. This may be attributed to the presence of ...

Science.gov (United States)

The nature of extralattice aluminum and its effect on acidity in zeolites was studied. A series of zeolites (some commercial), dealuminated by various methods, were obtained having Si/Al ratios between 1.5 and 20. These were characterized using volumetric sorption, XRD, AA, NMR, and reaction studies. Samples dealuminated using ammonium hexafluorosilicate were found to contain little or no extralattice aluminum. In contrast, steam-dealuminated zeolites had large amounts of extralattice aluminum. In some cases a significant portion of the extralattice aluminum was unobservable by [sup 27]Al NMR, suggesting the existence of an aluminum species of low symmetry. Proton NMR indicated that all the protons were associated with the lattice aluminum atoms. Depending on the preparation history, different groups of H-Y zeolites exhibited different maxima in catalytic ...

CERN Document Server

Third World Congress on Oxidation Catalysis

UK PubMed Central (United Kingdom)

Aluminum toxicity is a major problem in agriculture worldwide. Among the cultivated Triticeae, rye (Secale cereale L.) is one of the most Al tolerant and represents an important potential...Full Text Available

Science.gov (United States)

Not Available

International Nuclear Information System (INIS)

... aluminum calcium calcium 45 cations citric acid corrosion inhibition radiation

Science.gov (United States)

Aluminum electrolytic capacitors, with 1043 failures, are a good example. Also, categorization by size and voltage reveals such frequencies of occurrence as ...

Science.gov (United States)

PMID:21846114

Energy Technology Data Exchange (ETDEWEB)

Aluminum hydroxide coatings on fuel elements stored in aluminum canisters in K West Basin were measured in July and August 1998. Good quality data was produced that enabled statistical analysis to determine a bounding value for aluminum hydroxide at a 99% confidence level. The updated bounding value is 10.6 kg per Multi-Canister Overpack (MCO), compared to the previously estimated bounding value of 8 kg/MCO. Thermal analysis using the updated bounding value, shows that the MCO generates oxygen concentrate that are below the lower flammability limits during the 40-year interim storage period and are, therefore, acceptable.

Science.gov (United States)

A number of alloys of zirconium have been investigated as part of a program aimed at improving the high-temperature tensile and creep strength of zirconium. These alloys include aluminum, beryllium, lead, magnesium, molybdenum, niobium, tantalum, tin, titanium, tungsten, vanadium, and zinc, binary and ternary alloys. The data indicate that aluminum, lead, molybdenum niobium, tin, titanium, tungsten, and vanadium can be used successfully to harden zirconium, and that aluminum, tin, titanium, and vanadium are particularly effective in maintaining the strength of zirconium at elevated temperatures.

International Nuclear Information System (INIS)

Available in abstract form only. Full text of publication follows: The application spectrum of X-ray and Gamma radiation is increasing exponentially in the area of diagnostic, nuclear medicine, food preservation, nuclear power plants and strategic utilities. To prevent the harmful effects of these radiations, shielding materials based on lead metal and its compounds are being used historically, which are toxic in nature. To protect environment it has become necessary to develop non-toxic lead free shielding materials. The use of titanium metal and its compounds as synthetic rock i.e. SYNROC are reported to be very effective non-toxic shielding materials for various applications. Red mud waste generated in aluminum producing industries possesses a unique mineralogical compositions containing fairly high quantity of titanium oxide and iron oxide useful for making non toxic shielding compositions and therefore red mud has been ...

Science.gov (United States)

This project proposes to design and develop a new class of power converters (direct DC to AC) to drastically improve performance and optimize the cost, size, weight and volume of the DC to AC converter in SOFC systems. The proposed topologies employ a high frequency link; direct DC to AC conversion approach. The direct DC to AC conversion approach is more efficient and operates without an intermediate dc-link stage. The absence of the dc-link, results in the elimination of bulky, aluminum electrolytic capacitors, which in turn leads to a reduction in the cost, volume, size and weight of the power electronic converter. The feasibility of two direct DC to AC converter topologies and their suitability to meet SECA objectives will be investigated. Laboratory proto-type converters (3-5kW) will be designed and tested in Phase-1. A detailed design trade-off study along with the test results will be available in the form of a report for the evaluation of SECA Industrial ...

Energy Technology Data Exchange (ETDEWEB)

A multiple metal oxide sorbent supported on a zeolite of substantially silicon oxide is used for the desulfurization of process gas streams, such as from a coal gasifier, at temperatures in the range of about 1200.degree. to about 1600.degree. F. The sorbent is provided by a mixture of copper oxide and manganese oxide and preferably such a mixture with molybdenum oxide. The manganese oxide and the molybdenum are believed to function as promoters for the reaction of hydrogen sulfide with copper oxide. Also, the manganese oxide inhibits the volatilization of the molybdenum oxide at the higher temperatures.

KoreaScience (Korea)

Full Text Available

Science.gov (United States)

Aluminum electrolytic capacitors are presently not allowed on NASA missions because they outgas water and organic vapors, as well as H2. As a consequence, much larger and heavier packages of tantalum capacitors are used. A hermetically sealed aluminum capacitor has been developed under NASA-MSFC SBIR contracts. This capacitor contains a nongassing electrolyte that was developed for this application so internal pressure would remain low. Capacitors rated at 250 to 540 V have been operated under full load for thousands of hours at 85 and 105 C with good electrical performance and low internal pressure. Electrolyte chemistry and seal engineering concepts will be discussed.

International Nuclear Information System (INIS)

Three copper-based alloys, CDA 102 (oxygen-free, high-purity copper), CDA 613 (aluminum bronze), and CDA 715 (Cu-30Ni), are candidates for the fabrication of high-level radioactive-waste disposal containers. Waste will include spent fuel assemblies from reactors as well as borosilicate glass, and will be sent to the prospective repository site at Yucca Mountain in Nye County, Nevada. The decay of radionuclides will result in the generation of substantial heat and in fluxes of gamma radiation outside the containers. In this environment, container materials might degrade by atmospheric oxidation, general aqueous phase corrosion, localized corrosion (LC), and stress corrosion cracking (SCC). This volume is a critical survey of available data on pitting and crevice corrosion of the copper-based candidates. Pitting and crevice corrosion are two of the most common forms of LC of these materials. Data on the SCC of these alloys is surveyed in Volume ...

International Nuclear Information System (INIS)

After being pre-plated a zinc layer, an amorphous Al-Mn alloy coating was applied onto the surface of AZ31B magnesium alloy with a bath of molten salts. Then the corrosion performance of the coated magnesium alloy was examined in 3.5% NaCl solution by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The results showed that the single Zn layer was active in the test solution with a high corrosion rate while the Al-Mn alloy coating could effectively protect AZ31B magnesium alloy from corrosion in the solution. The high corrosion resistance of Al-Mn alloy coating was ascribed to an intact and stable passive film formed on the coating. The performances of the passive film on Al-Mn alloy were further investigated by Mott-Schottky curve and X-ray photoelectron spectroscopy (XPS) analysis. It was confirmed that the passive film exhibited n-type semiconducting behavior in 3.5% NaCl solution with a carrier density two orders of magnitude less than that formed on ...

Science.gov (United States)

... Airframe System Technoloqies Laser fabricated flooring Composite sandwich panels for noise control Spray formed HS aluminum alloys Protective ...

Science.gov (United States)

... The LVS bulk capacitance can be implemented using high temperature aluminum electrolytic capacitors with relatively low component volume. ...

Science.gov (United States)

Quantitative determination of Broensted acid site concentrations in calcined H-mordenite and H-ZSM-5 by means of conductometric titration and infrared spectroscopy reveals that the concentration of Broensted acid sites present is lower than would be expected on the basis of the aluminum content. This discrepancy is attributed to dealumination and dehydroxylation processes occurring during calcination. A model is proposed according to which the degree of these processes strongly depends on the concentration of vicinal aluminum T sites in the zeolite: Broensted acid sites associated with these T sites are lost, and the remaining Broensted acidity is related to the concentration of the (remaining) isolated aluminum T sites. This model quantitatively correlates the experimentally determined concentration of Broensted acid sites with the concentration of isolated aluminum T sites. 33 refs., 4 figs., 2 tabs.

Energy Technology Data Exchange (ETDEWEB)

Developing models for the electrical behavior of exploding bridgewire circuits requires high-quality data of a type not usually generated in routine tests of detonator hardware. To obtain a precise measurement of the time of bridgewire burst relative to current start, one must simultaneously record the current, i, and either di/dt or the voltage across the bridgewire. To fully develop and test a model it is also necessary to vary the bridgewire cross sections and geometry, firing circuit characteristics and charging voltage for the firing circuits over as wide a range as possible. As a part of developing an electrical model for aluminum and copper bridgewires, we have conducted parameter studies on some flat copper and aluminum bridgewires. Most of the work was done on aluminum bridgewires, with a few experiments on copper. We will report the experimental results from these studies and compare them with model predictions.

Energy Technology Data Exchange (ETDEWEB)

There is no abstract currently available for this item

British Library Electronic Table of Contents (United Kingdom)

This study compares two series of solvents for application in aluminum electrolytic capacitors: ethylene glycol (EG) and water mixtures, and ethylene glycol and 1-n-butyl-3-methylimidazolium tetrafluoroborate (BMI.BF4) ionic liquid (IL) mixtures. Electrochemical impedance spectroscopy and cyclic voltammetry were carried out with a previously anodized aluminum disk electrode. Comparative measurements of solution resistance, polarization resistance, AC capacitance, and passive current were made. The results show that EG?IL mixtures with low amounts of IL (10% IL?90% EG v/v) have a low solution resistance. Low values of solution resistance, high values of polarization resistance, small passive current, and uniform capacitance of anodized aluminum in EG?IL mixtures are favorable properties of ...

Science.gov (United States)

... o Application - Aluminum electrolytic capacitors provide the tallest voluse, mass and cost per microfarad except for tan- , talum capacitors. ...

British Library Electronic Table of Contents (United Kingdom)

Ultrasonic gold and aluminum wire wedge bonding are widely used for electrical and signal interconnections of the integrated circuit chip packages. In this paper, based on the metallurgical theories and thermal aging test methods, the long-term thermal reliabilities of gold and aluminum wire wedge bonding on aluminum and Au/Ni/Cu pads, were investigated, respectively. At 200degreeC, the Au/Al bond interfaces evolved little when the storage time was less than 48h; with the aging time increasing, the interfacial intermetallic compounds (IMC) grew up from the pad (vertical growth); the primary compounds were Au5Al2 near the bond toe and heel, and Au2Al at the periphery. Then, the thickness of IMC was unchanged, and extended horizontally (lateral growth), Au5Al2 transformed into more stable Au...

International Nuclear Information System (INIS)

It is essential that alumina used for manufacturing electronic devices should contain an extremely low level of alpha-radiation. The principal source of alpha-radiation in alumina is uranium, a minor source being thorium. Uranium in bauxite dissolves into the liquor in the digestion process and is fixed to the red mud as the desilication reaction progresses. A part of uranium remaining in the liquor precipitates together with aluminum hydroxide in the precipitation process. The uranium content of aluminum hydroxide becomes lower as the precipitation velocity per unit surface area of the seed becomes slower. Organic matters in the Bayer liquor has an extremely significant impact on the uranium content of aluminum hydroxide. Aluminum hydroxide free of uranium is obtainable from the liquor that does not contain organic matters.

KoreaScience (Korea)

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International Nuclear Information System (INIS)

... ammonium compounds benzilic acid chemical preparation lanthanum oxides

Science.gov (United States)

The need for cost effective, high performance, long life capacitors with improved reliability is discussed. It is shown that a low cost, miniature aluminum capacitor, with improved reliability and proven life, can be produced with existing technology. It is further shown that the capacitor can be specified for 125 C life and shelf test requirements, and meet established standards for their parametric performance.

UK PubMed Central (United Kingdom)

32P-Postlabeling analysis and enzyme-linked immunosorbent assay (ELISA) have been used to detect DNA adducts in peripheral blood lymphocytes from primary aluminum production plant workers who were exposed...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The electrometallurgical treatment process described in this paper builds on our experience in treating spent fuel from the Experimental Breeder Reactor (EBR-II). The work is also to some degree, a spin-off from applying electrometallurgical treatment to spent fuel from the Hanford single pass reactors (SPRs) and fuel and flush salt from the Molten Salt Reactor Experiment (MSRE) in treating EBR-II fuel, we recover the actinides from a uranium-zirconium fuel by electrorefining the uranium out of the chopped fuel. With SPR fuel, uranium is electrorefined out of the aluminum cladding. Both of these processes are conducted in a LiCl-KCl molten-salt electrolyte. In the case of the MSRE, which used a fluoride salt-based fuel, uranium in this salt is recovered through a series of electrochemical reductions. Recovering high-purity uranium from an aluminum-matrix fuel is more challenging than treating SPR or EBR-II fuel because the ...

Science.gov (United States)

The dealumination of mordenite by acidification (HCl, HNO/sub 3/) and by SiCl/sub 4/ and steaming treatments is followed by high-resolution magic-angle-spinning solid-state /sup 29/Si and /sup 27/Al NMR spectroscopy. The combined use of these techniques leads to the determination of the silicon-aluminum ordering. It is demonstrated that aluminum atoms preferentially occupy tetrahedral positions in the four-membered rings of the mordenite structure. In addition, a mechanism of dealumination can be inferred, consisting in removing the aluminum atoms two by two from the four-membered rings. It is also possible to compute the number of SiOH groups left in the unit cell after the progressive removal of aluminum atoms: four groups per extracted Al atom are generated in the beginning of dealumination and this number gradually decreases to two, suggesting that a structural reorganization must necessarily occur ...

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Interest in finding out passive ways to keep the variation in the indoor climate within the comfort zone is gaining in popularity. One possible solution is the use of the moisture-buffering property of materials. In this study, the effects of the ventilation system and moisture-buffering properties of the building fabric on the stability of the indoor temperature and humidity are analysed by means of long-term field measurements. Indoor climate measurements were carried out in 170 detached houses (248 rooms). Temperature and relative humidity were measured continuously in bedrooms and living rooms at one-hour intervals over a one-year period. In general, it may be concluded that in this study, the ventilation had a greater effect on the indoor climate than the properties of the building fabric. The dampening effect of hygroscopic materials was remarkably less in the field measurements than it was in simulations in different studies. This indicates that completely non-hygroscopic and ...

Science.gov (United States)

The induced radioactivity in the construction materials of a Cockcroft-- Walton type neutron generator was measured. Major activation products (/sup 24/ Na, /sup 28/Al, /sup 56/Mn, /sup 64/Cu, /sup 65/Ni, /sup 69m/Zn, /sup 88/Rb /sup 91/Sr /sup 101/Mo, /sup 187/W/ and resulting doses are tabulated. Results show that the highest gamma activities would be observed in the fluorescent bulbs, copper pipe, aluminum lattice rod, and the aluminum pipe clamp. Thermoluminescent dosimeter readings yield the highest doses for the copper pipe tee, copper pipe, and aluminum lattice rod. Results of measuremerts of the neutron and gamma dose profiles of the facility are shown. However the indication is clearly that the tritium target, compared to other components, is the major source of radiation both during and after shutdown. (UK)

International Nuclear Information System (INIS)

We have measured K-edge X-ray absorption spectra of argon in sputtered aluminum films at a synchrotron radiation facility (the Photon Factory). We found that the energy and shape of white line change when the film is annealed at 500 C and the spectrum becomes resembling that of argon implanted in silicon. From the analyses of the X-ray absorption spectra and TEM observation we concluded that argon exists as very small atom clusters with a diameter less than 1 nm or exist as isolated atoms in the as-sputtered aluminum film, and that the size of the clusters become as big as 10 nm diameter when the film is heated. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

International Nuclear Information System (INIS)

The performance of scanning driver circuits fabricated with self-aligned aluminum gate polysilicon thin-film transistors (TFT's) is demonstrated. After the gate electrode patterning, the fabrication process temperature is kept below 400degC to enable the use of aluminum gate electrodes. The low-temperature crystallization phenomenon, which occurs when protons are implanted simultaneously with boron or phosphorus dopants, is employed to eliminate the 600degC activation-annealing process. A maximum clock frequency of about 2.0 MHz is achieved when the driver operating voltage is 24 V and the TFT channel length is 12 #mu#m. (author).

Energy Technology Data Exchange (ETDEWEB)

Focus Ion Beam (FIB) milling has greatly extended the utility of atom probe and TEM because it enables sample preparation with a level of dimensional control never before possible. Using FIB it is possible to extract the samples from desired and very specific locations. The artifacts associated with this sample preparation method must also be fully understood. In this work issues specifically relevant to the FIB milling of aluminum alloys are presented. After using the FIB as a sample preparation technique it is evident that gallium will concentrate in three areas of the sample: on the surface, on grain boundaries and at interphase boundaries. This work also shows that low energy Ar ion nanomilling is potentially quite effective for removing gallium implantation layers and gallium from the internal surfaces of aluminum thin foils.

J-STORE (Japan)

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International Nuclear Information System (INIS)

Short communication.

Energy Technology Data Exchange (ETDEWEB)

Short communication

International Nuclear Information System (INIS)

Bi-U mixed oxides were synthesized by two methods and characterized by X-ray diffraction and X-ray photoelectron spectroscopy. The samples were tested for the catalytic oxidation of carbon monoxide by oxygen. A stepwise redox mechanism consistent with the kinetic results is proposed. (orig.).

International Science & Technology Center (ISTC)

Development of Method and Technical Project of the Plant for Thermo-Vacuum Desorption of Tritium Oxide (HTO) from the Environmental Samples

KoreaScience (Korea)

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Science.gov (United States)

... CONDUCTOR 11,5-209 CAPACITORS II,A-2, 11,5-144 ALTITUDE EFFECTS 11,5-160 ALUMINUM ELECTROLYTIC CAPACITORS 11,5-145 ...

Science.gov (United States)

Aluminium (Al) toxicity, affecting around half of the world¿s arable land, severely hinders the ability of crop plants to utilize moisture and nutrients by restricting root growth and function. Among the cultivated cereals, rye is the most Al-tolerant and represents an important potential source of ...

Science.gov (United States)

twenty 350 V, 2.5 mF aluminum electrolytic capacitors with 10.8 mH inductors made of multi-strand wire. The PFN discharge was controlled using an silicon ...

Science.gov (United States)

the network were assembled of custom 450 volt Aluminum electrolytic capacitors provided by the Mallory Capacitor Company. A comparison between theoretical ...

UK PubMed Central (United Kingdom)

In an attempt to establish if cross protection can be induced by different strains of Haemophilus parasuis, three groups of 12 gnotobiotic pigs were immunized each with an aluminum hydroxide adsorbed...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Experience at SRS, ORNL, BNL, and Georgia Institute of Technology involving irradiated aluminum clad fuel and target elements, as well as studies of non-irradiated aluminum indicate that some types of aluminum assemblies can be kept in a continually well-deionized water atmosphere for up to 25 years without problems. SRS experience ranges from 2.75 years for the L-1.1 charge kept in deionized D{sub 2}O{sup 1} to greater than 10 years for assemblies stored in the Receiving Basin for Off-site Fuel (RBOF){sup 2}. Experience at Georgia Institute of Technology reactor in Atlanta yielded the longest value of 25 years without problems. The common denominators in all of the reports is that the water is continually deionized to approximately 2 M{Omega} (2 {times} 10{sup 6}ohms) resistivity and the containers for the water are stainless steel or other non-porous material. This resistivity value is equivalent to a value of 0.5 ...

Energy Technology Data Exchange (ETDEWEB)

Using an expanded nuclear data base, the activation of nitrogen, aluminum, iron, nickel, copper, zirconium, niobium, molybdenum, tungsten, and lead were calculated for the first wall positions of the STARFIRE and MARS conceptual fusion reactors.

Energy Technology Data Exchange (ETDEWEB)

Thermodynamic states encountered during combustion of Aluminum powder in Shock-Dispersed-Fuel (SDF) explosions were analyzed with the Cheetah code. Results are displayed in the Le Chatelier diagram: the locus of states of specific internal energy versus temperature. Accuracy of the results was confirmed by comparing the fuel and products curves with the heats of detonation and combustion, and species composition as measured in bomb calorimeter experiments. Results were fit with analytic functions u = f(T) suitable for specifying the thermodynamic properties required for gas-dynamic models of combustion in explosions.

Energy Technology Data Exchange (ETDEWEB)

Zeolite Y is the active component of most commercial cracking catalysts. Interaction of H[sub 3]PO[sub 4] with extraframework aluminum of ultra-stable zeolite (USY) leads to the formation of different types of aluminum phosphates, while there is no indication of the formation of SAPO zeotype structures. The total acidity of USY slightly decreases upon the H[sub 3]PO[sub 4] treatment, while the maximum in the distribution of acid strength is shifted to milder acidities. Dealumination of the zeolite and creation of POH sites associated with AIPO[sub 4] are responsible for the modifications observed. 37 refs., 8 figs., 3 tabs.

International Nuclear Information System (INIS)

A mixture of powders of silica and aluminum nitride is subjected to high-energy ball milling for different milling times. This material is subsequently compacted by uniaxial pressing and sintered at 1450 deg. C. The resulting pellets are crushed and analysed by X-ray diffraction. For short milling times, the amount of phase transformation is minimal and the resulting material mostly consists of cristobalite and aluminum nitride. For long milling times, nanocrystalline #beta#-SiAl_2O_2N_2 is mainly produced.

International Nuclear Information System (INIS)

The uranium target of a gas jet transport system for fission products has been modified by the addition of an aluminum cover foil. The new modification allows fission fragments of low mass to enter a continuous chemistry system while heavier fragments are stopped in the aluminum. The elimination of the heavier homologues allows development of simpler and faster chemical separation procedures. In addition, since the lighter fragments are slowed down by the cover foil a smaller target chamber can be used. This leads to a reduction in system holdup time. (orig.).

Energy Technology Data Exchange (ETDEWEB)

We investigated the effects of additives to the etching solution of 1 M hydrochloric acid on the electrochemical etching behavior for aluminum electrolytic capacitors, using scanning and transmission electron microscopy, and AC impedance spectroscopy. For the addition of 1 M sulfuric acid or 5% ethylene glycol to the hydrochloric acid solution, the distribution of etch tunnels was more uniform with high density of etch pits compared with that without addition. The highest specific surface area was obtained from the electrolyte with 5% ethylene glycol additive. The correlation of internal morphologies of etched foils with impedance parameters was interpreted by impedance techniques.

Science.gov (United States)

A process is provided for conducting organic compound conversion over a catalyst composition comprising a specially treated crystalline zeolite having a high initial silica-to-alumina mole ratio, said zeolite having been synthesized from a reaction mixture comprising a diamine as a cation source. The treatment of the zeolite material comprises the sequential steps of reacting the zeolite with a dilute hydrogen fluoride solution, contacting the hydrogen fluoride solution reacted material with aluminum chloride vapor, and then treating the aluminum chloride contacted material to convert it to hydrogen form.

British Library Electronic Table of Contents (United Kingdom)

Oxidation of propylene with oxygen, air and a mixture of nitrogen?oxygen in a barrier discharge is investigated. The selectivity towards formation of propylene oxide in pure oxygen is shown to be as high as 45 wt% and the propylene conversion ratio is found to be 12.9 wt%. In the oxidation with air, the propylene oxide selectivity is 23 wt%, while the conversion is 7.5 wt%. The values of propylene conversion and selectivity towards formation of propylene oxide in a barrier discharge are consistent with those obtained by the thermocatalytic methods for production of propylene oxide.

Energy Technology Data Exchange (ETDEWEB)

The electrochemical oxidation as a method to destroy drug residues like Aspirin {sup trademark}, tetracycline or gentamicin in water was investigated with C-Anode (modified by manganese oxides) and Pt Anode. The mechanism of Aspirin {sup trademark} and tetracycline oxidation and the influence of the biocide effect was observed using GC-MS and three different microbiological tests. In general the biological availability increases with progressive oxidation of the antibiotics. (orig.)

UK PubMed Central (United Kingdom)

The widely accepted oxidative stress theory of aging postulates that aging results from accumulation of oxidative damage. Surprisingly, data from the longest-living rodent known, naked mole-rats [MRs;...Full Text Available

UK PubMed Central (United Kingdom)

Oxidative stress occurs when the level of prooxidants exceeds the level of antioxidants in cells resulting in oxidation of cellular components and consequent loss of cellular function. Oxidative...Full Text Available

Science.gov (United States)

The catalytic effects of copper-aluminium-magnesium oxides in the oxidative coupling of phenylethyne is described. The importance of surface properties as a redox site are discussed.

UK PubMed Central (United Kingdom)

Potato tuber mitochondria oxidizing malate respond to NAD⁺ addition with increased oxidation rates, whereas mung bean hypocotyl mitochondria do not. This is traced to a low endogenous content...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Apparatus and method for selective measurement of tritium oxide in an environment which may include other radioactive components and gamma radiation, the measurement including the selective separation of tritium oxide from a sample gas through a membrane into a counting gas, the generation of electrical pulses individually representative by rise times of tritium oxide and other radioactivity in the counting gas, separation of the pulses by rise times, and counting of those pulses representative of tritium oxide. The invention further includes the separate measurement of any tritium in the sample gas by oxidizing the tritium to tritium oxide and carrying out a second separation and analysis procedure as described above.

Science.gov (United States)

The growth of an oxide interfacial layer was recently found to increase the open-circuit voltage (OCV) and efficiency by up to 60 per cent in GaAs metal-semiconductor solar cells. Details of oxidation techniques to provide the necessary oxide thickness and chemical structure and using ozone, water-vapor-saturated oxygen, or oxygen gas discharges are described, as well as apparent crystallographic orientation effects. Preliminary results of the oxide chemistry obtained from X-ray, photoelectron spectroscopy are given. Ratios of arsenic oxide to gallium oxide of unity or less seem to be preferable. Samples with the highest OVC predominantly have As(+3) in the arsenic oxide rather than As(+5). A major difficulty at this time is a reduction in OCV by 100-200 mV when the antireflection coating is vacuum deposited.

UK PubMed Central (United Kingdom)

PurposeCataracts are often considered to be an unavoidable consequence of aging. Oxidative damage is a major cause or consequence of cortical and nuclear cataracts, the most common...Full Text Available

Science.gov (United States)

Metastable yttrium-oxide films are synthesized using reactive sputter deposition. The yttrium concentration of the as-deposited film is found to vary as a function of the sputter deposition rate. In addition to the synthesis of the cubic equilibrium phase...

Energy Technology Data Exchange (ETDEWEB)

This patent describes a catalyst composition. It consists of the catalytic oxides of iron, bismuth, molybdenum and magnesium as essential components and optionally the oxides of cobalt, nickel, phosphorus and arsenic.

Science.gov (United States)

May 31, 2011 ... A Theoretical Solid Oxide Fuel Cell Model for System Controls and Stability Design AUTHOR(S): Kopasakis, George; Brinson, Thomas; Credle, ...

International Nuclear Information System (INIS)

Synthesis of Eu-doped #beta#- and 15R-SiAlONs was studied by the ammonia nitridation of precursors derived from an #alpha#-Si_3N_4 fine powder dispersed in aluminum glycine gel with various Si/Al ratio and post-annealing in a nitrogen pressure furnace. The largest amount of #beta#-SiAlON was observed in the product at 1750 deg. C for Si/Al = 1/1 with small amounts of both #alpha#- and 15R-SiAlON impurities. The product showed two emissions at around 420 nm and 560 nm. The emission intensities decreased with increasing amount of #beta#-SiAlON. The former and latter emissions were assigned to Eu"2"+ in the 15R- and #alpha#-SiAlONs impurities. A mixture of Eu-doped 15R-SiAlON with #alpha#-Al_2O_3 impurity was obtained for Si/Al = 1/6, using AlN together with Al(NO_3)_3.9H_2O in a 2/1 atomic ratio as the aluminum source. It showed a bluish-white emission at 450 nm under 254 nm radiation.

Energy Technology Data Exchange (ETDEWEB)

Since ionic liquids (ILs) possess several attractive properties, including chemical and thermal stability, nonflammability, high ionic conductivity, and negligible vapor pressure, a new electrolyte system based on ILs has been proposed for chip type aluminum electrolytic capacitors. Four ILs based on imidazolium/pyrrolidinium cations and maleate/phthalate anions have been synthesized and their thermal stabilities have been examined. The 25wt.% solutions of the four ILs in gamma-butyrolactone (GBL) solvent were prepared as electrolytes of chip type aluminum electrolytic capacitors. The conductivity, sparking voltage and thermal stability of these electrolytes have been systematically investigated. The results revealed that the four IL-based electrolytes exhibited high conductivity. Furthermore, the conductivity of maleate anion-based electrolytes is higher than that of phthalate anion-based electrolytes, whereas the high-temperature durability ...

Energy Technology Data Exchange (ETDEWEB)

Red mud is a waste product of the aluminium refining industry. It is composed of aluminium hydroxide and iron oxide. This study examined the feasibility of using red mud as a catalyst to eliminate volatile organic compounds in atmospheric pollutants. Volatile organic compounds can be eliminated by thermal oxidation between 600 and 1100 degrees C. However, the oxidation of volatile organic compounds can also be accomplished at lower temperatures (200 to 450 degrees C) if a catalyst is present. Currently, the low temperature destruction of volatile organic compounds is not widespread because of the difficulty in deactivating the catalyst. In this study, red mud was calcined in air at 500 degrees C. Under such conditions, the red mud converts to aluminium oxide and iron oxide. These 2 oxides are active and are carbon dioxide selective in the ...

Energy Technology Data Exchange (ETDEWEB)

The morphology and size characteristics of the population of AlP particles produced by treatment of a pure aluminium melt with an Al-Fe-P inoculant addition have been determined. The particles are shown to be polyhedral like the primary silicon they nucleate in hypereutectic Al-Si alloy melts and to be prone to clustering at increased phosphorus addition levels. The number of AlP particles per unit area is shown to be comparable with the corresponding number density of polyhedral primary silicon in Al-20 wt.% Si treated in the same way under identical conditions which is consistent with earlier conclusions that AlP acts as a nucleation catalyst for primary silicon in hypereutectic Al-Si casting alloys. (orig.)

International Nuclear Information System (INIS)

Reactively sputtered tantalum nitride (Ta_2N) has been investigated as a diffusion barrier between Pd_2Si and aluminum and CoSi_2 and Al. Ta_2N is found to be an excellent matallurgical diffusion barrier for the two systems up to 555 "0C, with no intermixing observed in Rutherford backscattering and Auger electron spectroscopic studies. Schottky barrier devices n-Si/Pd_2Si/Ta_2N/Al were excellent and showed no deterioration after annealing at 500 "0C. However, similar devices with CoSi_2 contacts and Ta_2N barrier showed a creation of high contact resistance between the silicide and the as-deposited nitride.

International Nuclear Information System (INIS)

Continuous freestanding SiC(Al) films were fabricated by melt spinning the aluminum-containing polycarbosilane (A-PCS) precursor. The results showed that the films contained #beta#-SiC crystals, #alpha#-SiC nano-crystals, C clusters and small amount of Al_4O_4C and Al_4SiC_4. The Al atoms in the films played important roles as both sintering aids and grain growth inhibitor. The PL spectrum showed a wide luminescence band from 320 nm to 440 nm, and the origin of PL centered at 385 nm might be related to the #alpha#-SiC nano-crystals using quantum size effects. The obtained films are expected to have important applications in MEMS for the environment of high temperature and optoelectronic devices.

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A procedure was developed for separating rubidium from irradiated aluminum encapsulated uranium. The separations procedure produces a final ultra-high purity RbCl product for subsequent high performance mass spectrometric analysis. The procedure involves first removing most of the macro-components and fission products by strong base anion exchange using, first, concentrated HCl, then oxalic acid media and second, selectively separating rubidium from alkaline-earth ions and other alkali-metal ions, including cesium, using Bio-Rex-40 cation-exchange resin. The resultant RbCl is then put through a final vacuum sublimation step. Ultra-pure reagents and specially clean glassware are used throughout the procedure to minimize contamination by naturally-occurring rubidium.

Energy Technology Data Exchange (ETDEWEB)

A method for preparing metal for heating by infrared radiance to enable uniform and consistent heating. The surface of one or more metal parts, such as aluminum or aluminum alloy parts, is treated to alter the surface finish to affect the reflectivity of the surface. The surface reflectivity is evaluated, such as by taking measurements at one or more points on the surface, to determine if a desired reflectivity has been achieved. The treating and measuring are performed until the measuring indicates that the desired reflectivity has been achieved. Once the treating has altered the surface finish to achieve the desired reflectivity, the metal part may then be exposed to infrared radiance to heat the metal part to a desired temperature, and that heating will be substantially consistent throughout by virtue of the desired reflectivity.

British Library Electronic Table of Contents (United Kingdom)

Erosion-corrosion (E-C) of 3003 aluminum (Al) alloy in ethylene glycol-water solutions were studied by weight-loss and electrochemical measurements as well as surface characterization through an impingement jet system. Al alloy E-C is dominated by erosion components, i.e., pure erosion and corrosion-enhanced erosion, which account for 92-97% of the total E-C rate under the various conditions in this work. Contribution from corrosion components, including pure corrosion and erosion-enhanced corrosion, is slight. With the increase of fluid flow velocity and sand concentration, the total E-C rate increases. Compared with the significant increase of the rates of erosion components, the increase of the rate of corrosion component is negligible. Upon fluid flow, passivity of Al alloy that develo...

Energy Technology Data Exchange (ETDEWEB)

Thermophotovoltaic (TPV) converters were developed and tested at the heat source operating temperature of 1,700 K. Rare-earth-doped yttrium aluminum garnet (YAG) and lutetium yttrium aluminum garnet (Lu, YAG) selective emitters, as well as a blackbody emitter, were coupled to InGaAs/InP photovoltaic (PV) cells and bandpass/infrared (IR) reflector filters. YAG-based selective emitters were adopted with Ho, Tm, and Er. PV cells had bandgaps of 0.51, 0.57, and 0.69 eV. Converter energy conversion efficiencies approaching 30%, as well as electrical output power densities near 2 W/cm{sup 2} were demonstrated. The overall performance of the filtered blackbody-based converter was found to be superior to the selective emitter YAG-based converters. The details of the measurements performed on the above converters and their individual components are presented.

Energy Technology Data Exchange (ETDEWEB)

In order to improve the well-known short operational life time of BF3 counters, three potential adsorbents for impurity gases (graphite, activated charcoal and a zirconium-aluminum mixture) were introduced into BF3 counters in the form of coating on the aluminum cathode surface. Tests in el fields revealed that a partial coating of activated charcoal provides the best result. The improvement of their operational life in el fields was about three orders of magnitude in terms of tolerable exposure. Many counters with a partial coating of activated charcoal were further tested from the following viewpoints: background noise, vibration and shock, el pulse discrimination, operational life in a neutron field and non-operational in-reactor exposure life. The results were satisfactory for reactor control and protection usage. (author).

Energy Technology Data Exchange (ETDEWEB)

Red mud is a waste generated by the aluminum industry, and its disposal is a major problem for this industry. Very rich in iron, it can be used as cheap pigment for colored concrete. The red coloration can be enhanced by calcination in the range of 600 to 800 C. Such operation also transforms the aluminum hydroxides (goethite and boehmite) and clays minerals into pozzolanic admixtures that are able to consume the calcium hydroxide produced by cement hydration. Thus, it is possible to develop a new admixture for concrete: a pozzolanic pigment. The pozzolanic properties of calcined red mud were investigated by monitoring lime consumption of different mixtures of OPC and red mud. The main products of hydration were C-S-H and mono-carboaluminate (C{sub 4}A{bar C}H{sub 11}). A uniform and durable colored concrete was obtained using white cement interground with 11% of burnt red mud.

British Library Electronic Table of Contents (United Kingdom)

Abstract Electronic structures of two representative zigzag and armchair models of aluminum phosphide nanotube (AlPNT) were investigated by density functional theory calculations. The structures were optimized and the bond lengths, tip diameters, band gaps, and dipole moments were calculated. Moreover, the quadrupole coupling constants (CQ) were calculated for the Al-27 atoms of the optimized structures. The same values of AlP bond lengths were calculated for both models. The larger value of band gap of armchair model than the zigzag model indicated the stronger dielectric property for the former model. The values of CQ(27Al) were the largest for the Al atoms placed at the tips of both zigzag and armchair AlPNT than other Al atoms, which could reveal dominant role of the Al atoms placed at...

KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

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KoreaScience (Korea)

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J-STORE (Japan)

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International Nuclear Information System (INIS)

Short communication.

KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

The influence of MeV electrons irradiation on the gate oxide layers of hydrogenated polysilicon thin film transistors (TFTs) was investigated by measuring gate leakage currents and threshold voltages. The experimental data revealed a decrease of oxide trap density and increase of positive oxide charge. Improvement in the interface roughness and in the oxide quality near the bottom interface was observed.

KoreaScience (Korea)

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J-STORE (Japan)

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KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

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KoreaScience (Korea)

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KoreaScience (Korea)

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International Nuclear Information System (INIS)

The RKR potential energy curves are constructed for the ground states of diatomic hafnium oxide and thorium oxide. Using Lippincott and Hulburt-Hirschfelder potential function the dissociation energies are estimated by curve fitting method. The H-H potential function was found to give a better fit in both cases. The dissociation energies of hafnium oxide and thorium oxide are estimated as 9.04 #+-# 0.02 eV and 10.34 #+-# 0.01 eV respectively. (author).

Science.gov (United States)

PMID:11506019

Energy Technology Data Exchange (ETDEWEB)

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KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

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Energy Technology Data Exchange (ETDEWEB)

Targets for heterogeneous transmutation of americium are composed of a support material, the inert matrix and of an americium oxide compound: AmO{sub 2-x} or Am{sub 2}O{sub 3}. In parallel to the studies using americium, simulated compounds of americium oxide, chosen amongst lanthanide oxides, are used. The selection of these compounds is based on theoretical, physical and crystallochemical considerations. In order to assess the influence of impurities composed of lanthanide oxides, resulting from the separation process, on the physical and chemical properties of such a target, synthesis of oxide powders containing impurities associated with the simulated americium oxide, characterizations, crystallographic studies and sodium compatibility tests have been performed. (author)

British Library Electronic Table of Contents (United Kingdom)

Desulphurization of gasoline and kerosene was carried out using organic and inorganic oxidants. Among the organic oxidants used were hydrogen peroxide in combination with acetic acid, formic acid, benzoic acid and butyric acid, while inorganic oxidants used included potassium permanganate and sodium perchlorate. The oxidation of each petroleum oil was carried out in two steps; the first step consisted of oxidation of the feed at moderate temperature and atmospheric pressure while in the second step, the oxidized mixture was extracted with azeotropic mixture of acetonitrile-water. A maximum desulphurization has occurred with NaClO4 and hydrogen peroxide and acetic acid, which are 68% and 61%, respectively in case of gasoline and 66% and 63%, respectively in case of kerosene oil. The FTIR st...

Energy Technology Data Exchange (ETDEWEB)

A kinetic model based on the Mars-van Krevelen mechanism that allows to describe the microkinetics of the heterogeneously catalysed partial oxidation of {alpha}, {beta}-unsaturated aldehydes is presented. This conversion is represented by a network, composed of the oxidation of the {alpha}, {beta}-unsaturated aldehyde towards the {alpha}, {beta}-unsaturated carboxylic acid and the consecutive oxidation of the acid as well as the parallel reaction of the aldehyde to products of deeper oxidation. The reaction steps of aldehyde respectively acid oxidation and catalyst reoxidation have been investigated separately in transient experiments. The combination of steady state and transient experiments has led to an improved understanding of the interaction of the catalyst with the aldehyde and the carboxylic acids as well as to a support of the kinetic model assumptions. (orig.)

Energy Technology Data Exchange (ETDEWEB)

The oxidative dehydrodimerization of propylene to C/sub 3/-dimers (1,5-hexadiene and benzene) has been examined at 600/sup 0/C and atmospheric pressure using a (Bi/sub 2/O/sub 3/)/sub 0.85/(La/sub 2/O/sub 3/)/sub 0.15/ oxide ion-conducting catalyst in a reactor where a catalyst disk separates a feed of propylene in helium from air. The surface of the disk exposed to propylene was reoxidized not by gaseous O/sub 2/, but by the dissociative adsorption and reduction of dioxygen at the oxidant side of the disk, followed by oxide ion conduction to replace spent lattice oxygen. Selectivity to C/sub 3/-dimers when using lattice oxide migration to reoxidize the catalyst was considerably greater than when O/sub 2/ was added to the propylene feed under the same reaction conditions. This result supports the proposal that lattice oxygen is predominantly involved in the selective ...

Energy Technology Data Exchange (ETDEWEB)

This work reports studies of ethanol oxidation on Pt-Sn/C catalysts with nearly the same particle size and identical overall composition having different amounts of oxide and alloyed phases. Results of characterization of physical properties by transmission electron microscopy (TEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC), X-ray photoelectron spectroscopy (XPS), and in situ dispersive X-ray absorption spectroscopy (DXAS) are presented. The variation in the amount of oxide and alloyed phases, promoted by heat treatments in mild temperature conditions, does not produce any significant particle growth. Cyclic voltammetry and oxidation of adsorbed CO in acid medium are used to probe the surface conditions. Data on the electrocatalytic activity towards ethanol oxidation, obtained by potential sweeps and chronoamperometry, are discussed and correlate well with ...

International Nuclear Information System (INIS)

The procedure of charge-coupled devices (CCD) are investigated by using MOS capacitors for enhancing their ionizing radiation tolerance. Authors have found that the gate oxidation temperature, thickness of SiO_2 gate insulator and high temperature processes after gate oxidation are crucial for determining the radiation tolerance of the devices, and proposed to decrease the thickness of gate insulator, perform gate oxidation at 1000 deg C by means of dry oxidation and minimize the number of high temperature procedure steps after gate oxidation. All stated above is a necessary preparation for priducing radiation hardened charge-coupled devices.

Science.gov (United States)

A radioactive particle was analyzed to discover the composition of the inactive material of the particle. The method uses the x-ray line spectrum of the K series caused by electron irradiation of the particle in the electron microscope. Iron and aluminum or silicon (the last two could not be distinguished) were found as inactive components in the particle. (D.L.C.)

Science.gov (United States)

Silicone-rubber washers function as damping and articulating elements in cast-aluminum spacers that separate bundle subconductors in each phase of extra-high-voltage transmission lines. Spacer/dampers are located every 3 ft. along transmission lines on Canada's first operational 500 and 735 kV system.

Energy Technology Data Exchange (ETDEWEB)

Non-destructive methods for measuring the remaining anticorrosive or antioxidative ability of coatings are investigated. For anticorrosive chromium coatings the increasing ferromagnetism caused by loss of chromium is measured by a permeability probe. Measured values on blades after operation are correlated with the progress of corrosion as determined by metallographic methods. For antioxidative aluminum coatings the diminishing layer thickness is taken as indication for the exhaustion of their protection ability. The layer thickness is measured eddy current probes, especially developed for this application.

British Library Electronic Table of Contents (United Kingdom)

A formula is obtained which describes the kinetics of low-temperature radiation hardening caused by creation of dislocation loops of interstitial type during irradiation. The radiation hardening of aluminum and vanadium is estimated using this formula and results of experiments on studying processes of nucleation and growth of interstitial dislocation loops in these materials by transparent electron microscopy. It is shown that the proposed formula is valid for description of the kinetics of low-temperature radiation hardening.

International Nuclear Information System (INIS)

The high-power model of Disk-and Washer (DAW) cavity for electron acceleration is under fabrication. Basic Dimensions of the cavity were determined from aluminum model measurement and electromagnetic field calculation. We have fabricated model made of OFC (Oxygen Free Copper) five times in total. Some details are optimized and corrected, and then the final brazing are proceeding. These model results and present status are described. (author)

Energy Technology Data Exchange (ETDEWEB)

An austenitic alloy having good thermal stability and resistance to sodium corrosion at 700.degree. C. consists essentially of 35-45% nickel 7.5-14% chromium 0.8-3.2% molybdenum 0.3-1.0% silicon 0.2-1.0% manganese 0-0.1% zirconium 2.0-3.5% titanium 1.0-2.0% aluminum 0.02-0.1% carbon 0-0.01% boron and the balance iron.

Energy Technology Data Exchange (ETDEWEB)

The purpose of this DOE-funded effort is to develop continuous processes for solvent extraction of coal for the production of carbon products. These carbon products include materials used in metals smelting, especially in the aluminum and steel industries, as well as porous carbon structural material referred to as ''carbon foam'' and carbon fibers. During this reporting period, efforts have focused on the facility modifications for continuous hydrotreating, as well as developing improved protocols for producing synthetic pitches.

Science.gov (United States)

Aluminium toxicity is a major problem in agriculture worldwide. Among the cultivated triticeae, rye (Secale cereale L.) is one of the most Al-tolerant and represents an important potential source of Al-tolerance for improvement of wheat. The Alt4 Al-tolerance locus of rye contains a cluster of genes...

Energy Technology Data Exchange (ETDEWEB)

With an objective to learn reactivity of coal at its surface, surfaces of oxidized coal samples were investigated. Miike coal was oxidized by using {sup 18}O2 in a closed loop system. As the reaction progresses, proportion of CO2 including isotopes increased rapidly as a result of oxidation of CO sites existing in the coal and the newly generated C{sup 18}O sites. The oxidizing reaction progressed via oxygen adsorbing sites generated near the surface, and oxygen containing groups. An FT-IR analysis estimated the depth of the oxidized layer to be 10{mu}m or less from particle surface. The oxidized coal was pulverized to see its surface condition. Functional groups introduced by the oxidation enter into the vicinity of the surface in a form to desorb as CO. CO2 is trapped in inner pores. The coal surface was observed by using an atomic force ...

Energy Technology Data Exchange (ETDEWEB)

In recent years, the influences of acid rain such as the acidification of lake water, on bio-system by the heavy metals from effluent of soils with acid rain and also on the structural materials of buildings are seriously discussed. Sulfur and nitrogen that are contained in fossil fuels are released into the atmosphere by the fuel combustion as their oxides dissolve in rain drops as sulfite and nitrous ions, where they are further oxidized into sulfate and nitrate ions These ions lower the pH of rain water resulting so-called acid rain. Therefore, it is important to accurately determine these ions in rain water for the investigation of reality of acid rain. However, it is not easy to accurately determine these ions, especially for sulfite ions in rain water, since they are quickly oxidized by the catalytic action of metallic ions such as ferric and manganous ions. And light, temperature, pH of solution and also species and ...

International Nuclear Information System (INIS)

The construction materials used in coolant systems in nuclear power plants become covered with oxide films as a result of exposure to the aqueous environment. The susceptibility of the materials to different forms of corrosion, as well as the extent of the incorporation of radioactive species on the surfaces of the primary circuit, are greatly influenced by the physical and chemical properties of these oxide films. The composition and characteristics of the oxide films in turn depend on the applied water chemistry. This work was undertaken in order to collect and evaluate the present views on the structure and behaviour of oxide films formed on iron- and nickel-based materials in aqueous environments. This survey should serve to recognise the areas in which more understanding and research effort is needed. The review begins with a discussion on the bulk oxides of iron, nickel and ...

International Nuclear Information System (INIS)

The morphological development of oxide scales formed on a low Al substituted #beta#-sialon (z=0.2) oxidised for time periods up to 1024h at 1350 C is discussed in relation to oxidation kinetics. The oxidation process is observed to be accompanied by changes in both the phase assemblage of the external layers and their morphology. Thus as the time of oxidation increases beyond 64h the cristobalite-#beta#-yttrium disilicate phase assemblage changes to cristobalite plus #beta#- and #gamma#-yttrium disilicate. In addition to the changes observed for the surface layers, differences are observed in the morphologies of the polished cross-sections. These changes are consistent with an order of magnitude decrease in oxidation rate. (orig.).

Science.gov (United States)

... Accession Number : ADD141533. Title : Yttrium Oxides in Vacuum-Plasma- Sprayed CoNiCrAlY Coatings,. Descriptive Note : Journal Article,. ...

Wastenet

Emissions and residues: Emissions may include, inter alia, nitrogen oxides, carbon monoxide, sulphur dioxide and other oxides

UK PubMed Central (United Kingdom)

Reactive oxygen species (ROS), inevitable byproducts of aerobic metabolism, are known to cause oxidative damage to cells and molecules. This, in turn, is widely accepted as a pivotal determinant of...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The influence of surface oxides of variable composition and nonstoichiometry formed at high temperatures in air on the general corrosion resistance of ferritic chromium steel type 08H17T (Fe-17Cr-1Ti) in weak sulfuric acid has been studied. Anodic passive films formed on steel with different pretreatments have also been examined. The surface oxide of nearly stoichiometric composition formed at 300 C provides for the passive state of steel in sulfuric acid despite its depletion by chromium when compared with that for nonstoichiometric Cr-enriched oxide formed at 600 C. The dissolution and transformation of nonstoichiometric thermal surface oxide in sulfuric acid appear to take place through defect sites, {minus}Fe{sup 2+} ions, and oxygen vacancies of the n-type conductor. The passive film formed on the nonstoichiometric oxide film, which had been produced at 600 C, was found to be ...

Science.gov (United States)

... ADD137758. Title : The Oxidation Behavior of CoCrAlY, CoCrAl and Yttrium-Implanted CoCrAl Alloys Compared and Contrasted,. ...

Energy Technology Data Exchange (ETDEWEB)

A catalytic process for the oxidation of sulfur-containing gases , E.G., sulfur dioxide and simultaneous production of sulfuric acid wherein a sulfur-containing gas is reacted with an oxygencontaining gas in the presence of a catalyst comprising an iron group metal on a solid support comprising a zeolite in a silicaalumina matrix.

UK PubMed Central (United Kingdom)

The gelation kinetics of an in situ gelable hydrogel formulated from oxidized dextran (Odex) and N-carboxyethyl chitosan (CEC) were investigated rheologically. Both Schiff base...Full Text Available

British Library Electronic Table of Contents (United Kingdom)

Rheological properties of moderately concentrated solutions of cellulose in methylmorpholine N-oxide-dimethylformamide mixtures containing hydrophilic montmorillonite nanoparticles were studied. Film composite materials were prepared, and their physicomechanical properties and structural organization were studied.

UK PubMed Central (United Kingdom)

We report the use of cysteine-substituted mutants in conjunction with in situ oxidation to determine the physical proximity of a pair of engineered cysteines in the pore region of the voltage-gated...Full Text Available

UK PubMed Central (United Kingdom)

A multidisciplinary approach was used to study the effects of pollution from a marine fish farm on nitrification rates and on the community structure of ammonia-oxidizing bacteria in the underlying...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The OH-initiated photo-oxidation of n-butane was used as a source of 1- and 2-butoxy radicals. Reactions producing ketones and other organic compounds are explained. Rates of photolysis were determined and are discussed.

UK PubMed Central (United Kingdom)

Oxidative stress has been implicated in the etiology of age-related muscle loss (sarcopenia). However, the underlying mechanisms by which oxidative stress contributes to sarcopenia have not been thoroughly...Full Text Available

UK PubMed Central (United Kingdom)

Neurons in the hippocampal CA1 region are particularly sensitive to oxidative stress (OS), whereas those in CA3 are resistant. To uncover mechanisms for selective CA1 vulnerability to OS, we...Full Text Available

UK PubMed Central (United Kingdom)

Quantitative probing of heterogeneous regions in muscle is feasible with phosphorus-31 magnetic resonance spectroscopy because of the differentiation of metabolic patterns of glycolytic and oxidative...Full Text Available

UK PubMed Central (United Kingdom)

Bacterial nitric oxide synthases (bNOS) are present in many Gram-positive species and have been demonstrated to synthesize NO from arginine in vitro and in vivo. However, the physiological role...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The oxidation conditions were investigated for obtaining a higher productivity in the production of high strength carbon fiber from polyacrylonitrile (PAN). The effect of incorporation of 2 % comonomer such as methyl acrylate (MA), acrylate containing carboxylate (SA), acrylamide (AAm), and hydroxyethyl acrylate (HEA) on the oxidation conditions was also investigated. The measurement of DSC and bonded oxygen content revealed that the most effective comonomer for promoting the cyclization of nitril group and the bonding of oxygen was found to be SA, and the second best was AAm. The measurement of tensile strength of carbon fiber showed that the copolymer of SA, HEA, and MA gave a high strength fiber. It took a long time to oxidize the carbon fiber when it was oxidized at a temperature on which double layer structure was not formed. To shorten the production time, a method of combining the upper limit ...

UK PubMed Central (United Kingdom)

Systemic administration of lipopolysaccharide (LPS), which causes endotoxemia and systemic inflammation, has been reported to induce expression of the gene for type II inducible nitric oxide synthase...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The electrochemical behavior of lanthanide oxides in molten alkaline chloride media is of great concern in pyrochemical processes for advanced nuclear fuel cycle. We have studied the solubilities of various lanthanide oxides in LiCl-KCl eutectic melt. In general, lanthanide oxides appeared to be insoluble/sparingly soluble in LiCl-KCl eutectic at 723 K. However, europium oxide exhibited an abnormal behavior in solubility and redox chemistry. The solubility of europium oxide was measured to be 1-2 order of magnitude higher than those of other lanthanide oxides. This abnormal solubility may be attributable to different electrochemical behavior of europium in the same experimental conditions. Most lanthanides ion exists as trivalent oxidation states. However, we observed divalent europium dissolved in LiCl-KCl molten salt by applying electron ...

Energy Technology Data Exchange (ETDEWEB)

This patent describes a method comprising applying a passivation layer of CaF{sub 2} to the surface of a superconductive ceramic oxide by evaporation. The CaF{sub 2} layer is effective to passivate the oxide surface without disrupting the superconductive properties.

UK PubMed Central (United Kingdom)

There is increasing evidence of a biochemical link between lipid oxidation and bone metabolism. Paraoxonase 1 (PON1) prevents the oxidation of low-density lipoprotein (LDL) and metabolizes biologically...Full Text Available

UK PubMed Central (United Kingdom)

Anionic peroxidase from tomato (Lycopersicon esculentum) fruit oxidized indoleacetic acid (IAA) slowly in the presence of Mn²⁺ and dichlorophenol in acetate buffers. The...Full Text Available

UK PubMed Central (United Kingdom)

Evolution of nitrogen oxides (NO_(x), primarily as nitric oxide) from soybean (Glycine max [L.] Merr.) leaves during purged in vivo nitrate reductase assays...Full Text Available

Science.gov (United States)

A detection theory is developed for point-contact metal-oxide-metal (MOM) systems. A system with heterogeneous oxide strongly bonded to the substrate is considered. It is shown that the form of the functional connection between the barrier heights and the ultimate compressive strength of the oxide has no substantial influence on the voltage-current characteristics of the system. Quantitative analysis indicates that a MOM system can behave as a tunnel diode and as a diode with a Schottky barrier. The model permits the determination of the optimum construction of long-life detectors based on MOM point-contacts.-

KoreaScience (Korea)

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KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

Green River oil shale was air oxidized at subretorting temperatures. Off gases consisting of nitrogen, oxygen, carbon monoxide, carbon dioxide, and water were monitored and quantitatively determined. A mathematical model of the oxidation reactions based on a shrinking core model has been developed. This model incorporates the chemical reaction of oxygen and the organic material in the oil shale as well as the diffusivity of the oxygen into the shale particle. Diffusivity appears to be rate limiting for the oxidation. Arrhenius type equations, which include a term for oil shale grade, have been derived for both the chemical reaction and the diffusivity.

KoreaScience (Korea)

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Wastenet

However, these intra-industrial structural changes are not considered in this bottom-up study.

Energy Technology Data Exchange (ETDEWEB)

Objective of the project is characterization of electrode reactions in molten salt by using metal oxides and silica-based electrode. The scope of project are characterization of metal oxide properties in molten salt and miniaturization of 3-electrode electrochemical test cell. Electrochemical micro-cell for actinide-LiCl-KCl molten salt was newly designed. Electroless and electrochemical deposition technique was applied to Mo coating on quartz tube. From the design of electrode and 3-electrode electrochemical cell suitable for the tests in molten salt electrolyte, so it is anticipated to get the information on the electrochemical behavior of metallic electrode in molten salt and to secure the information on oxidation/reduction behavior of actinide

Energy Technology Data Exchange (ETDEWEB)

Promoted antimony phosphate oxide complexes are excellent catalysts for the ammoxidation of methanol to HCN especially at high methanol throughputs.

Energy Technology Data Exchange (ETDEWEB)

This articles deals with an approach that has given some key information about the mechanisms of the liquid phase oxidation of butane to acetic acid. This procedure has been developed over the last 34 years; however, much of what will be discussed represents a synthesis of previous insights. Many of the observations are relatively recent and have not been previously published. In principle, this approach should be applicable to many oxidation processes. (orig.)

UK PubMed Central (United Kingdom)

The application of kinetic probes that allow one to determine relative reactivities of biologically relevant substrates with oxidizing intermediates in the Fenton reagent (H2O2 plus Fe2+ in acidic aqueous...Full Text Available

Science.gov (United States)

The authors have determined quantitative characteristics for oxide films forming on (111) surfaces of cadmium telluride single crystals on anodic oxidation in 0.1 M KOH: the constants in the Guenterschulze-Betz equation and the film growth constant, which is 2.4 nm/V, from which the activation energy for cadmium telluride electrooxidation has been calculated.

International Nuclear Information System (INIS)

During electrolysis of a "2"4"8Cm(III) solution in 2M K_2CO_3 at pH=13, partial oxidation of curium to a higher oxidation state, probably Cm(IV), was observed. The absorption spectra of Cm(III) and Cm(IV) in K_2CO_3 solution were recorded and the molar extinction coefficients of main absorption bands of curium were evaluated. (author).

UK PubMed Central (United Kingdom)

AQ4N (1,4-bis([2-(dimethylamino-N-oxide)ethyl]amino)5,8-dihydroxy- anthracene-9,10-dione) is a novel alkylaminoanthraquinone N-oxide which, on reduction, forms a stable DNA affinic cytotoxic compound...Full Text Available